diff mbox series

[v11,15/15] media: vim2m-audio: add virtual driver for audio memory to memory

Message ID 1700637838-6743-16-git-send-email-shengjiu.wang@nxp.com
State Superseded
Headers show
Series Add audio support in v4l2 framework | expand

Commit Message

Shengjiu Wang Nov. 22, 2023, 7:23 a.m. UTC
Audio memory to memory virtual driver use video memory to memory
virtual driver vim2m.c as example. The main difference is
device type is VFL_TYPE_AUDIO and device cap type is V4L2_CAP_AUDIO_M2M.

The device_run function is a dummy function, which is simply
copy the data from input buffer to output buffer.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
---
 drivers/media/test-drivers/Kconfig       |  11 +
 drivers/media/test-drivers/Makefile      |   1 +
 drivers/media/test-drivers/vim2m-audio.c | 799 +++++++++++++++++++++++
 3 files changed, 811 insertions(+)
 create mode 100644 drivers/media/test-drivers/vim2m-audio.c

Comments

Hans Verkuil Jan. 17, 2024, 10:32 a.m. UTC | #1
On 22/11/2023 08:23, Shengjiu Wang wrote:
> Audio memory to memory virtual driver use video memory to memory
> virtual driver vim2m.c as example. The main difference is
> device type is VFL_TYPE_AUDIO and device cap type is V4L2_CAP_AUDIO_M2M.
> 
> The device_run function is a dummy function, which is simply
> copy the data from input buffer to output buffer.
> 
> Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
> ---
>  drivers/media/test-drivers/Kconfig       |  11 +
>  drivers/media/test-drivers/Makefile      |   1 +
>  drivers/media/test-drivers/vim2m-audio.c | 799 +++++++++++++++++++++++
>  3 files changed, 811 insertions(+)
>  create mode 100644 drivers/media/test-drivers/vim2m-audio.c
> 
> diff --git a/drivers/media/test-drivers/Kconfig b/drivers/media/test-drivers/Kconfig
> index 459b433e9fae..55f8af6ee4e2 100644
> --- a/drivers/media/test-drivers/Kconfig
> +++ b/drivers/media/test-drivers/Kconfig
> @@ -17,6 +17,17 @@ config VIDEO_VIM2M
>  	  This is a virtual test device for the memory-to-memory driver
>  	  framework.
>  
> +config VIDEO_VIM2M_AUDIO
> +	tristate "Virtual Memory-to-Memory Driver For Audio"
> +	depends on VIDEO_DEV
> +	select VIDEOBUF2_VMALLOC
> +	select V4L2_MEM2MEM_DEV
> +	select MEDIA_CONTROLLER
> +	select MEDIA_CONTROLLER_REQUEST_API

Drop this. This option has been removed.

> +	help
> +	  This is a virtual audio test device for the memory-to-memory driver
> +	  framework.
> +
>  source "drivers/media/test-drivers/vicodec/Kconfig"
>  source "drivers/media/test-drivers/vimc/Kconfig"
>  source "drivers/media/test-drivers/vivid/Kconfig"
> diff --git a/drivers/media/test-drivers/Makefile b/drivers/media/test-drivers/Makefile
> index 740714a4584d..0c61c9ada3e1 100644
> --- a/drivers/media/test-drivers/Makefile
> +++ b/drivers/media/test-drivers/Makefile
> @@ -10,6 +10,7 @@ obj-$(CONFIG_DVB_VIDTV) += vidtv/
>  
>  obj-$(CONFIG_VIDEO_VICODEC) += vicodec/
>  obj-$(CONFIG_VIDEO_VIM2M) += vim2m.o
> +obj-$(CONFIG_VIDEO_VIM2M_AUDIO) += vim2m-audio.o
>  obj-$(CONFIG_VIDEO_VIMC) += vimc/
>  obj-$(CONFIG_VIDEO_VIVID) += vivid/
>  obj-$(CONFIG_VIDEO_VISL) += visl/
> diff --git a/drivers/media/test-drivers/vim2m-audio.c b/drivers/media/test-drivers/vim2m-audio.c
> new file mode 100644
> index 000000000000..72806ada8628
> --- /dev/null
> +++ b/drivers/media/test-drivers/vim2m-audio.c
> @@ -0,0 +1,799 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * A virtual v4l2-mem2mem example for audio device.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/delay.h>
> +#include <linux/fs.h>
> +#include <linux/sched.h>
> +#include <linux/slab.h>
> +
> +#include <linux/platform_device.h>
> +#include <media/v4l2-mem2mem.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-ioctl.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-event.h>
> +#include <media/videobuf2-vmalloc.h>
> +#include <sound/dmaengine_pcm.h>
> +
> +MODULE_DESCRIPTION("Virtual device for audio mem2mem testing");
> +MODULE_LICENSE("GPL");
> +
> +static unsigned int debug;
> +module_param(debug, uint, 0644);
> +MODULE_PARM_DESC(debug, "debug level");
> +
> +#define MEM2MEM_NAME "vim2m-audio"
> +
> +#define dprintk(dev, lvl, fmt, arg...) \
> +	v4l2_dbg(lvl, debug, &(dev)->v4l2_dev, "%s: " fmt, __func__, ## arg)
> +
> +#define SAMPLE_NUM 4096
> +
> +static void audm2m_dev_release(struct device *dev)
> +{}
> +
> +static struct platform_device audm2m_pdev = {
> +	.name		= MEM2MEM_NAME,
> +	.dev.release	= audm2m_dev_release,
> +};
> +
> +static u32 formats[] = {
> +	V4L2_AUDIO_FMT_S16_LE,
> +};
> +
> +#define NUM_FORMATS ARRAY_SIZE(formats)
> +
> +/* Per-queue, driver-specific private data */
> +struct audm2m_q_data {
> +	unsigned int		rate;
> +	unsigned int		channels;
> +	unsigned int		buffersize;
> +	unsigned int		sequence;
> +	u32			fourcc;
> +};
> +
> +enum {
> +	V4L2_M2M_SRC = 0,
> +	V4L2_M2M_DST = 1,
> +};
> +
> +static snd_pcm_format_t find_format(u32 fourcc)
> +{
> +	snd_pcm_format_t fmt;
> +	unsigned int k;
> +
> +	for (k = 0; k < NUM_FORMATS; k++) {
> +		if (formats[k] == fourcc)
> +			break;
> +	}
> +
> +	if (k == NUM_FORMATS)
> +		return 0;
> +
> +	fmt = v4l2_fourcc_to_audfmt(formats[k]);
> +
> +	return fmt;
> +}
> +
> +struct audm2m_dev {
> +	struct v4l2_device	v4l2_dev;
> +	struct video_device	vfd;
> +
> +	struct mutex		dev_mutex;
> +
> +	struct v4l2_m2m_dev	*m2m_dev;
> +#ifdef CONFIG_MEDIA_CONTROLLER
> +	struct media_device	mdev;
> +#endif
> +};
> +
> +struct audm2m_ctx {
> +	struct v4l2_fh		fh;
> +	struct v4l2_ctrl_handler	ctrl_handler;
> +	struct audm2m_dev	*dev;
> +
> +	struct mutex		vb_mutex;
> +
> +	/* Source and destination queue data */
> +	struct audm2m_q_data   q_data[2];
> +};
> +
> +static inline struct audm2m_ctx *file2ctx(struct file *file)
> +{
> +	return container_of(file->private_data, struct audm2m_ctx, fh);
> +}
> +
> +static struct audm2m_q_data *get_q_data(struct audm2m_ctx *ctx,
> +					enum v4l2_buf_type type)
> +{
> +	if (type == V4L2_BUF_TYPE_AUDIO_OUTPUT)
> +		return &ctx->q_data[V4L2_M2M_SRC];
> +	return &ctx->q_data[V4L2_M2M_DST];
> +}
> +
> +static const char *type_name(enum v4l2_buf_type type)
> +{
> +	if (type == V4L2_BUF_TYPE_AUDIO_OUTPUT)
> +		return "Output";
> +	return "Capture";
> +}
> +
> +/*
> + * mem2mem callbacks
> + */
> +
> +/*
> + * device_run() - prepares and starts the device
> + */
> +static void device_run(void *priv)
> +{
> +	struct audm2m_ctx *ctx = priv;
> +	struct audm2m_dev *audm2m_dev;
> +	struct vb2_v4l2_buffer *src_buf, *dst_buf;
> +	struct audm2m_q_data *q_data_src, *q_data_dst;
> +	int src_size, dst_size = 0;
> +	short *src_addr, *dst_addr;
> +	int i;
> +
> +	audm2m_dev = ctx->dev;
> +
> +	q_data_src = get_q_data(ctx, V4L2_BUF_TYPE_AUDIO_OUTPUT);
> +	if (!q_data_src)
> +		return;
> +
> +	q_data_dst = get_q_data(ctx, V4L2_BUF_TYPE_AUDIO_CAPTURE);
> +	if (!q_data_dst)
> +		return;
> +
> +	src_buf = v4l2_m2m_next_src_buf(ctx->fh.m2m_ctx);
> +	dst_buf = v4l2_m2m_next_dst_buf(ctx->fh.m2m_ctx);
> +	src_buf->sequence = q_data_src->sequence++;
> +	dst_buf->sequence = q_data_dst->sequence++;
> +	v4l2_m2m_buf_copy_metadata(src_buf, dst_buf, false);
> +
> +	/* Process the conversion */
> +	src_size = vb2_get_plane_payload(&src_buf->vb2_buf, 0);
> +
> +	src_addr = vb2_plane_vaddr(&src_buf->vb2_buf, 0);
> +	dst_addr = vb2_plane_vaddr(&dst_buf->vb2_buf, 0);
> +
> +	if (q_data_src->rate == q_data_dst->rate) {
> +		memcpy(dst_addr, src_addr, src_size);
> +		dst_size = src_size;
> +	} else if (q_data_src->rate == 2 * q_data_dst->rate) {
> +		/* 8k to 16k */
> +		for (i = 0; i < src_size / 2; i++) {
> +			*dst_addr++ = *src_addr++;
> +			src_addr++;
> +		}
> +
> +		dst_size = src_size / 2;
> +	} else if (q_data_src->rate * 2 == q_data_dst->rate) {
> +		/* 16k to 8k */
> +		for (i = 0; i < src_size / 2; i++) {
> +			*dst_addr++ = *src_addr;
> +			*dst_addr++ = *src_addr++;
> +		}
> +
> +		dst_size = src_size * 2;
> +	}
> +
> +	vb2_set_plane_payload(&dst_buf->vb2_buf, 0, dst_size);
> +
> +	src_buf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
> +	dst_buf = v4l2_m2m_dst_buf_remove(ctx->fh.m2m_ctx);
> +
> +	v4l2_m2m_buf_done(src_buf, VB2_BUF_STATE_DONE);
> +	v4l2_m2m_buf_done(dst_buf, VB2_BUF_STATE_DONE);
> +	v4l2_m2m_job_finish(audm2m_dev->m2m_dev, ctx->fh.m2m_ctx);
> +}
> +
> +static int audm2m_querycap(struct file *file, void *priv,
> +			   struct v4l2_capability *cap)
> +{
> +	strscpy(cap->driver, MEM2MEM_NAME, sizeof(cap->driver));
> +	strscpy(cap->card, MEM2MEM_NAME, sizeof(cap->card));
> +	snprintf(cap->bus_info, sizeof(cap->bus_info),
> +		 "platform:%s", MEM2MEM_NAME);

You can drop this bus_info line, it's filled in for you.

> +
> +	return 0;
> +}
> +
> +static int enum_fmt(struct v4l2_fmtdesc *f)
> +{
> +	int i, num;
> +
> +	num = 0;
> +
> +	for (i = 0; i < NUM_FORMATS; ++i) {
> +		if (num == f->index)
> +			break;
> +		/*
> +		 * Correct type but haven't reached our index yet,
> +		 * just increment per-type index
> +		 */
> +		++num;
> +	}
> +
> +	if (i < NUM_FORMATS) {
> +		/* Format found */
> +		f->pixelformat = formats[i];
> +		return 0;
> +	}
> +
> +	/* Format not found */
> +	return -EINVAL;
> +}
> +
> +static int audm2m_enum_fmt_audio_cap(struct file *file, void *priv,
> +				     struct v4l2_fmtdesc *f)
> +{
> +	return enum_fmt(f);
> +}
> +
> +static int audm2m_enum_fmt_audio_out(struct file *file, void *priv,
> +				     struct v4l2_fmtdesc *f)
> +{
> +	return enum_fmt(f);
> +}
> +
> +static int audm2m_g_fmt(struct audm2m_ctx *ctx, struct v4l2_format *f)
> +{
> +	struct vb2_queue *vq;
> +	struct audm2m_q_data *q_data;
> +
> +	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
> +	if (!vq)
> +		return -EINVAL;
> +
> +	q_data = get_q_data(ctx, f->type);
> +	if (!q_data)
> +		return -EINVAL;
> +
> +	f->fmt.audio.audioformat = q_data->fourcc;
> +	f->fmt.audio.channels	= q_data->channels;
> +	f->fmt.audio.buffersize = q_data->buffersize;
> +
> +	return 0;
> +}
> +
> +static int audm2m_g_fmt_audio_out(struct file *file, void *priv,
> +				  struct v4l2_format *f)
> +{
> +	return audm2m_g_fmt(file2ctx(file), f);
> +}
> +
> +static int audm2m_g_fmt_audio_cap(struct file *file, void *priv,
> +				  struct v4l2_format *f)
> +{
> +	return audm2m_g_fmt(file2ctx(file), f);
> +}
> +
> +static int audm2m_try_fmt(struct v4l2_format *f, snd_pcm_format_t fmt)
> +{
> +	f->fmt.audio.channels = 1;
> +	f->fmt.audio.buffersize = f->fmt.audio.channels *
> +				  snd_pcm_format_physical_width(fmt) *
> +				  SAMPLE_NUM;
> +	return 0;
> +}
> +
> +static int audm2m_try_fmt_audio_cap(struct file *file, void *priv,
> +				    struct v4l2_format *f)
> +{
> +	snd_pcm_format_t fmt;
> +
> +	fmt = find_format(f->fmt.audio.audioformat);
> +	if (!fmt) {
> +		f->fmt.audio.audioformat = formats[0];
> +		fmt = find_format(f->fmt.audio.audioformat);
> +	}
> +
> +	return audm2m_try_fmt(f, fmt);
> +}
> +
> +static int audm2m_try_fmt_audio_out(struct file *file, void *priv,
> +				    struct v4l2_format *f)
> +{
> +	snd_pcm_format_t fmt;
> +
> +	fmt = find_format(f->fmt.audio.audioformat);
> +	if (!fmt) {
> +		f->fmt.audio.audioformat = formats[0];
> +		fmt = find_format(f->fmt.audio.audioformat);
> +	}
> +
> +	return audm2m_try_fmt(f, fmt);
> +}
> +
> +static int audm2m_s_fmt(struct audm2m_ctx *ctx, struct v4l2_format *f)
> +{
> +	struct audm2m_q_data *q_data;
> +	struct vb2_queue *vq;
> +	snd_pcm_format_t fmt;
> +
> +	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
> +	if (!vq)
> +		return -EINVAL;
> +
> +	q_data = get_q_data(ctx, f->type);
> +	if (!q_data)
> +		return -EINVAL;
> +
> +	if (vb2_is_busy(vq)) {
> +		v4l2_err(&ctx->dev->v4l2_dev, "%s queue busy\n", __func__);
> +		return -EBUSY;
> +	}
> +
> +	q_data->fourcc	= f->fmt.audio.audioformat;
> +	q_data->channels = f->fmt.audio.channels;
> +
> +	fmt = find_format(f->fmt.audio.audioformat);
> +	q_data->buffersize = q_data->channels *
> +			     snd_pcm_format_physical_width(fmt) *
> +			     SAMPLE_NUM;
> +
> +	dprintk(ctx->dev, 1,
> +		"Format for type %s: %d/%d, fmt: %c%c%c%c\n",
> +		type_name(f->type), q_data->rate,
> +		q_data->channels,
> +		(q_data->fourcc & 0xff),
> +		(q_data->fourcc >>  8) & 0xff,
> +		(q_data->fourcc >> 16) & 0xff,
> +		(q_data->fourcc >> 24) & 0xff);
> +
> +	return 0;
> +}
> +
> +static int audm2m_s_fmt_audio_cap(struct file *file, void *priv,
> +				  struct v4l2_format *f)
> +{
> +	int ret;
> +
> +	ret = audm2m_try_fmt_audio_cap(file, priv, f);
> +	if (ret)
> +		return ret;
> +
> +	return audm2m_s_fmt(file2ctx(file), f);
> +}
> +
> +static int audm2m_s_fmt_audio_out(struct file *file, void *priv,
> +				  struct v4l2_format *f)
> +{
> +	int ret;
> +
> +	ret = audm2m_try_fmt_audio_out(file, priv, f);
> +	if (ret)
> +		return ret;
> +
> +	return audm2m_s_fmt(file2ctx(file), f);
> +}
> +
> +static const struct v4l2_ioctl_ops audm2m_ioctl_ops = {
> +	.vidioc_querycap		= audm2m_querycap,
> +
> +	.vidioc_enum_fmt_audio_cap	= audm2m_enum_fmt_audio_cap,
> +	.vidioc_g_fmt_audio_cap		= audm2m_g_fmt_audio_cap,
> +	.vidioc_try_fmt_audio_cap	= audm2m_try_fmt_audio_cap,
> +	.vidioc_s_fmt_audio_cap		= audm2m_s_fmt_audio_cap,
> +
> +	.vidioc_enum_fmt_audio_out	= audm2m_enum_fmt_audio_out,
> +	.vidioc_g_fmt_audio_out		= audm2m_g_fmt_audio_out,
> +	.vidioc_try_fmt_audio_out	= audm2m_try_fmt_audio_out,
> +	.vidioc_s_fmt_audio_out		= audm2m_s_fmt_audio_out,
> +
> +	.vidioc_reqbufs			= v4l2_m2m_ioctl_reqbufs,
> +	.vidioc_querybuf		= v4l2_m2m_ioctl_querybuf,
> +	.vidioc_qbuf			= v4l2_m2m_ioctl_qbuf,
> +	.vidioc_dqbuf			= v4l2_m2m_ioctl_dqbuf,
> +	.vidioc_prepare_buf		= v4l2_m2m_ioctl_prepare_buf,
> +	.vidioc_create_bufs		= v4l2_m2m_ioctl_create_bufs,
> +	.vidioc_expbuf			= v4l2_m2m_ioctl_expbuf,
> +
> +	.vidioc_streamon		= v4l2_m2m_ioctl_streamon,
> +	.vidioc_streamoff		= v4l2_m2m_ioctl_streamoff,
> +
> +	.vidioc_subscribe_event		= v4l2_ctrl_subscribe_event,
> +	.vidioc_unsubscribe_event	= v4l2_event_unsubscribe,
> +};
> +
> +/*
> + * Queue operations
> + */
> +static int audm2m_queue_setup(struct vb2_queue *vq,
> +			      unsigned int *nbuffers,
> +			      unsigned int *nplanes,
> +			      unsigned int sizes[],
> +			      struct device *alloc_devs[])
> +{
> +	struct audm2m_ctx *ctx = vb2_get_drv_priv(vq);
> +	struct audm2m_q_data *q_data;
> +
> +	q_data = get_q_data(ctx, vq->type);
> +
> +	if (*nplanes)
> +		return sizes[0] < q_data->buffersize ? -EINVAL : 0;
> +
> +	*nplanes = 1;
> +	sizes[0] = q_data->buffersize;
> +
> +	dprintk(ctx->dev, 1, "%s: get %d buffer(s) of size %d each.\n",
> +		type_name(vq->type), *nplanes, sizes[0]);
> +
> +	return 0;
> +}
> +
> +static void audm2m_buf_queue(struct vb2_buffer *vb)
> +{
> +	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
> +	struct audm2m_ctx *ctx = vb2_get_drv_priv(vb->vb2_queue);
> +
> +	v4l2_m2m_buf_queue(ctx->fh.m2m_ctx, vbuf);
> +}
> +
> +static int audm2m_start_streaming(struct vb2_queue *q, unsigned int count)
> +{
> +	struct audm2m_ctx *ctx = vb2_get_drv_priv(q);
> +	struct audm2m_q_data *q_data = get_q_data(ctx, q->type);
> +
> +	q_data->sequence = 0;
> +	return 0;
> +}
> +
> +static void audm2m_stop_streaming(struct vb2_queue *q)
> +{
> +	struct audm2m_ctx *ctx = vb2_get_drv_priv(q);
> +	struct vb2_v4l2_buffer *vbuf;
> +
> +	for (;;) {
> +		if (V4L2_TYPE_IS_OUTPUT(q->type))
> +			vbuf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
> +		else
> +			vbuf = v4l2_m2m_dst_buf_remove(ctx->fh.m2m_ctx);
> +		if (!vbuf)
> +			return;
> +		v4l2_m2m_buf_done(vbuf, VB2_BUF_STATE_ERROR);
> +	}
> +}
> +
> +static const struct vb2_ops audm2m_qops = {
> +	.queue_setup	 = audm2m_queue_setup,
> +	.buf_queue	 = audm2m_buf_queue,
> +	.start_streaming = audm2m_start_streaming,
> +	.stop_streaming  = audm2m_stop_streaming,
> +	.wait_prepare	 = vb2_ops_wait_prepare,
> +	.wait_finish	 = vb2_ops_wait_finish,
> +};
> +
> +static int queue_init(void *priv, struct vb2_queue *src_vq,
> +		      struct vb2_queue *dst_vq)
> +{
> +	struct audm2m_ctx *ctx = priv;
> +	int ret;
> +
> +	src_vq->type = V4L2_BUF_TYPE_AUDIO_OUTPUT;
> +	src_vq->io_modes = VB2_MMAP | VB2_DMABUF;
> +	src_vq->drv_priv = ctx;
> +	src_vq->buf_struct_size = sizeof(struct v4l2_m2m_buffer);
> +	src_vq->ops = &audm2m_qops;
> +	src_vq->mem_ops = &vb2_vmalloc_memops;
> +	src_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
> +	src_vq->lock = &ctx->vb_mutex;
> +	src_vq->min_buffers_needed = 1;

Drop this, it's not needed.

> +
> +	ret = vb2_queue_init(src_vq);
> +	if (ret)
> +		return ret;
> +
> +	dst_vq->type = V4L2_BUF_TYPE_AUDIO_CAPTURE;
> +	dst_vq->io_modes = VB2_MMAP | VB2_DMABUF;
> +	dst_vq->drv_priv = ctx;
> +	dst_vq->buf_struct_size = sizeof(struct v4l2_m2m_buffer);
> +	dst_vq->ops = &audm2m_qops;
> +	dst_vq->mem_ops = &vb2_vmalloc_memops;
> +	dst_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
> +	dst_vq->lock = &ctx->vb_mutex;
> +	dst_vq->min_buffers_needed = 1;

Ditto.

> +
> +	return vb2_queue_init(dst_vq);
> +}
> +
> +static const s64 audm2m_rates[] = {
> +	8000, 16000,
> +};
> +
> +static int audm2m_op_s_ctrl(struct v4l2_ctrl *ctrl)
> +{
> +	struct audm2m_ctx *ctx =
> +		container_of(ctrl->handler, struct audm2m_ctx, ctrl_handler);
> +	int ret = 0;
> +
> +	switch (ctrl->id) {
> +	case V4L2_CID_M2M_AUDIO_SOURCE_RATE:
> +		ctx->q_data[V4L2_M2M_SRC].rate = ctrl->qmenu_int[ctrl->val];
> +		break;
> +	case V4L2_CID_M2M_AUDIO_DEST_RATE:
> +		ctx->q_data[V4L2_M2M_DST].rate = ctrl->qmenu_int[ctrl->val];
> +		break;
> +	default:
> +		ret = -EINVAL;
> +		break;
> +	}
> +
> +	return ret;
> +}
> +
> +static const struct v4l2_ctrl_ops audm2m_ctrl_ops = {
> +	.s_ctrl = audm2m_op_s_ctrl,
> +};
> +
> +/*
> + * File operations
> + */
> +static int audm2m_open(struct file *file)
> +{
> +	struct audm2m_dev *dev = video_drvdata(file);
> +	struct audm2m_ctx *ctx = NULL;
> +	snd_pcm_format_t fmt;
> +	int width;
> +	int rc = 0;
> +
> +	if (mutex_lock_interruptible(&dev->dev_mutex))
> +		return -ERESTARTSYS;
> +	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
> +	if (!ctx) {
> +		rc = -ENOMEM;
> +		goto open_unlock;
> +	}
> +
> +	v4l2_fh_init(&ctx->fh, video_devdata(file));
> +	file->private_data = &ctx->fh;
> +	ctx->dev = dev;
> +
> +	ctx->q_data[V4L2_M2M_SRC].fourcc = formats[0];
> +	ctx->q_data[V4L2_M2M_SRC].rate = 8000;
> +	ctx->q_data[V4L2_M2M_SRC].channels = 1;
> +
> +	/* Fix to 4096 samples */
> +	fmt = find_format(formats[0]);
> +	width = snd_pcm_format_physical_width(fmt);
> +	ctx->q_data[V4L2_M2M_SRC].buffersize = SAMPLE_NUM * width;
> +	ctx->q_data[V4L2_M2M_DST] = ctx->q_data[V4L2_M2M_SRC];
> +
> +	ctx->fh.m2m_ctx = v4l2_m2m_ctx_init(dev->m2m_dev, ctx, &queue_init);
> +
> +	mutex_init(&ctx->vb_mutex);
> +
> +	if (IS_ERR(ctx->fh.m2m_ctx)) {
> +		rc = PTR_ERR(ctx->fh.m2m_ctx);
> +
> +		v4l2_fh_exit(&ctx->fh);
> +		kfree(ctx);
> +		goto open_unlock;
> +	}
> +
> +	v4l2_fh_add(&ctx->fh);
> +
> +	dprintk(dev, 1, "Created instance: %p, m2m_ctx: %p\n",
> +		ctx, ctx->fh.m2m_ctx);
> +
> +	v4l2_ctrl_handler_init(&ctx->ctrl_handler, 2);
> +
> +	v4l2_ctrl_new_int_menu(&ctx->ctrl_handler, &audm2m_ctrl_ops,
> +			       V4L2_CID_M2M_AUDIO_SOURCE_RATE,
> +			       ARRAY_SIZE(audm2m_rates) - 1, 0, audm2m_rates);
> +	v4l2_ctrl_new_int_menu(&ctx->ctrl_handler, &audm2m_ctrl_ops,
> +			       V4L2_CID_M2M_AUDIO_DEST_RATE,
> +			       ARRAY_SIZE(audm2m_rates) - 1, 0, audm2m_rates);
> +
> +	if (ctx->ctrl_handler.error) {
> +		rc = ctx->ctrl_handler.error;
> +		v4l2_ctrl_handler_free(&ctx->ctrl_handler);
> +		goto err_ctrl_handler;
> +	}
> +
> +	ctx->fh.ctrl_handler = &ctx->ctrl_handler;
> +
> +	mutex_unlock(&dev->dev_mutex);
> +
> +	return 0;
> +
> +err_ctrl_handler:
> +	v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
> +open_unlock:
> +	mutex_unlock(&dev->dev_mutex);
> +	return rc;
> +}
> +
> +static int audm2m_release(struct file *file)
> +{
> +	struct audm2m_dev *dev = video_drvdata(file);
> +	struct audm2m_ctx *ctx = file2ctx(file);
> +
> +	dprintk(dev, 1, "Releasing instance %p\n", ctx);
> +
> +	v4l2_ctrl_handler_free(&ctx->ctrl_handler);
> +	v4l2_fh_del(&ctx->fh);
> +	v4l2_fh_exit(&ctx->fh);
> +	mutex_lock(&dev->dev_mutex);
> +	v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
> +	mutex_unlock(&dev->dev_mutex);
> +	kfree(ctx);
> +
> +	return 0;
> +}
> +
> +static void audm2m_device_release(struct video_device *vdev)
> +{
> +	struct audm2m_dev *dev = container_of(vdev, struct audm2m_dev, vfd);
> +
> +	v4l2_device_unregister(&dev->v4l2_dev);
> +	v4l2_m2m_release(dev->m2m_dev);
> +
> +#ifdef CONFIG_MEDIA_CONTROLLER
> +	media_device_cleanup(&dev->mdev);
> +#endif
> +	kfree(dev);
> +}
> +
> +static const struct v4l2_file_operations audm2m_fops = {
> +	.owner		= THIS_MODULE,
> +	.open		= audm2m_open,
> +	.release	= audm2m_release,
> +	.poll		= v4l2_m2m_fop_poll,
> +	.unlocked_ioctl	= video_ioctl2,
> +	.mmap		= v4l2_m2m_fop_mmap,
> +};
> +
> +static const struct video_device audm2m_videodev = {
> +	.name		= MEM2MEM_NAME,
> +	.vfl_dir	= VFL_DIR_M2M,
> +	.fops		= &audm2m_fops,
> +	.ioctl_ops	= &audm2m_ioctl_ops,
> +	.minor		= -1,
> +	.release	= audm2m_device_release,
> +	.device_caps	= V4L2_CAP_AUDIO_M2M | V4L2_CAP_STREAMING,
> +};
> +
> +static const struct v4l2_m2m_ops m2m_ops = {
> +	.device_run	= device_run,
> +};
> +
> +static const struct media_device_ops audm2m_media_ops = {
> +	.req_validate = vb2_request_validate,
> +	.req_queue = v4l2_m2m_request_queue,
> +};
> +
> +static int audm2m_probe(struct platform_device *pdev)
> +{
> +	struct audm2m_dev *dev;
> +	struct video_device *vfd;
> +	int ret;
> +
> +	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
> +	if (!dev)
> +		return -ENOMEM;
> +
> +	ret = v4l2_device_register(&pdev->dev, &dev->v4l2_dev);
> +	if (ret)
> +		goto error_free;
> +
> +	mutex_init(&dev->dev_mutex);
> +
> +	dev->vfd = audm2m_videodev;
> +	vfd = &dev->vfd;
> +	vfd->lock = &dev->dev_mutex;
> +	vfd->v4l2_dev = &dev->v4l2_dev;
> +
> +	video_set_drvdata(vfd, dev);
> +	platform_set_drvdata(pdev, dev);
> +
> +	dev->m2m_dev = v4l2_m2m_init(&m2m_ops);
> +	if (IS_ERR(dev->m2m_dev)) {
> +		v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem device\n");
> +		ret = PTR_ERR(dev->m2m_dev);
> +		dev->m2m_dev = NULL;
> +		goto error_dev;
> +	}
> +
> +#ifdef CONFIG_MEDIA_CONTROLLER
> +	dev->mdev.dev = &pdev->dev;
> +	strscpy(dev->mdev.model, MEM2MEM_NAME, sizeof(dev->mdev.model));
> +	snprintf(dev->mdev.bus_info, sizeof(dev->mdev.bus_info),
> +		 "platform:%s", MEM2MEM_NAME);
> +	media_device_init(&dev->mdev);
> +	dev->mdev.ops = &audm2m_media_ops;
> +	dev->v4l2_dev.mdev = &dev->mdev;
> +#endif
> +
> +	ret = video_register_device(vfd, VFL_TYPE_AUDIO, 0);
> +	if (ret) {
> +		v4l2_err(&dev->v4l2_dev, "Failed to register video device\n");
> +		goto error_m2m;
> +	}
> +
> +#ifdef CONFIG_MEDIA_CONTROLLER
> +	ret = v4l2_m2m_register_media_controller(dev->m2m_dev, vfd,
> +						 MEDIA_ENT_F_PROC_AUDIO_RESAMPLER);
> +	if (ret) {
> +		v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem media controller\n");
> +		goto error_v4l2;
> +	}
> +
> +	ret = media_device_register(&dev->mdev);
> +	if (ret) {
> +		v4l2_err(&dev->v4l2_dev, "Failed to register mem2mem media device\n");
> +		goto error_m2m_mc;
> +	}
> +#endif
> +
> +	v4l2_info(&dev->v4l2_dev,
> +		  "Device registered as /dev/v4l-audio%d\n", vfd->num);
> +
> +	return 0;
> +
> +#ifdef CONFIG_MEDIA_CONTROLLER
> +error_m2m_mc:
> +	v4l2_m2m_unregister_media_controller(dev->m2m_dev);
> +#endif
> +error_v4l2:
> +	video_unregister_device(&dev->vfd);
> +	/* audm2m_device_release called by video_unregister_device to release various objects */
> +	return ret;
> +error_m2m:
> +	v4l2_m2m_release(dev->m2m_dev);
> +error_dev:
> +	v4l2_device_unregister(&dev->v4l2_dev);
> +error_free:
> +	kfree(dev);
> +
> +	return ret;
> +}
> +
> +static void audm2m_remove(struct platform_device *pdev)
> +{
> +	struct audm2m_dev *dev = platform_get_drvdata(pdev);
> +
> +	v4l2_info(&dev->v4l2_dev, "Removing " MEM2MEM_NAME);
> +
> +#ifdef CONFIG_MEDIA_CONTROLLER
> +	media_device_unregister(&dev->mdev);
> +	v4l2_m2m_unregister_media_controller(dev->m2m_dev);
> +#endif
> +	video_unregister_device(&dev->vfd);
> +}
> +
> +static struct platform_driver audm2m_pdrv = {
> +	.probe		= audm2m_probe,
> +	.remove_new	= audm2m_remove,
> +	.driver		= {
> +		.name	= MEM2MEM_NAME,
> +	},
> +};
> +
> +static void __exit audm2m_exit(void)
> +{
> +	platform_driver_unregister(&audm2m_pdrv);
> +	platform_device_unregister(&audm2m_pdev);
> +}
> +
> +static int __init audm2m_init(void)
> +{
> +	int ret;
> +
> +	ret = platform_device_register(&audm2m_pdev);
> +	if (ret)
> +		return ret;
> +
> +	ret = platform_driver_register(&audm2m_pdrv);
> +	if (ret)
> +		platform_device_unregister(&audm2m_pdev);
> +
> +	return ret;
> +}
> +
> +module_init(audm2m_init);
> +module_exit(audm2m_exit);

Regards,

	Hans
Shengjiu Wang Jan. 18, 2024, 6:13 a.m. UTC | #2
On Wed, Jan 17, 2024 at 6:32 PM Hans Verkuil <hverkuil@xs4all.nl> wrote:
>
> On 22/11/2023 08:23, Shengjiu Wang wrote:
> > Audio memory to memory virtual driver use video memory to memory
> > virtual driver vim2m.c as example. The main difference is
> > device type is VFL_TYPE_AUDIO and device cap type is V4L2_CAP_AUDIO_M2M.
> >
> > The device_run function is a dummy function, which is simply
> > copy the data from input buffer to output buffer.
> >
> > Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
> > ---
> >  drivers/media/test-drivers/Kconfig       |  11 +
> >  drivers/media/test-drivers/Makefile      |   1 +
> >  drivers/media/test-drivers/vim2m-audio.c | 799 +++++++++++++++++++++++
> >  3 files changed, 811 insertions(+)
> >  create mode 100644 drivers/media/test-drivers/vim2m-audio.c
> >
> > diff --git a/drivers/media/test-drivers/Kconfig b/drivers/media/test-drivers/Kconfig
> > index 459b433e9fae..55f8af6ee4e2 100644
> > --- a/drivers/media/test-drivers/Kconfig
> > +++ b/drivers/media/test-drivers/Kconfig
> > @@ -17,6 +17,17 @@ config VIDEO_VIM2M
> >         This is a virtual test device for the memory-to-memory driver
> >         framework.
> >
> > +config VIDEO_VIM2M_AUDIO
> > +     tristate "Virtual Memory-to-Memory Driver For Audio"
> > +     depends on VIDEO_DEV
> > +     select VIDEOBUF2_VMALLOC
> > +     select V4L2_MEM2MEM_DEV
> > +     select MEDIA_CONTROLLER
> > +     select MEDIA_CONTROLLER_REQUEST_API
>
> Drop this. This option has been removed.
>
> > +     help
> > +       This is a virtual audio test device for the memory-to-memory driver
> > +       framework.
> > +
> >  source "drivers/media/test-drivers/vicodec/Kconfig"
> >  source "drivers/media/test-drivers/vimc/Kconfig"
> >  source "drivers/media/test-drivers/vivid/Kconfig"
> > diff --git a/drivers/media/test-drivers/Makefile b/drivers/media/test-drivers/Makefile
> > index 740714a4584d..0c61c9ada3e1 100644
> > --- a/drivers/media/test-drivers/Makefile
> > +++ b/drivers/media/test-drivers/Makefile
> > @@ -10,6 +10,7 @@ obj-$(CONFIG_DVB_VIDTV) += vidtv/
> >
> >  obj-$(CONFIG_VIDEO_VICODEC) += vicodec/
> >  obj-$(CONFIG_VIDEO_VIM2M) += vim2m.o
> > +obj-$(CONFIG_VIDEO_VIM2M_AUDIO) += vim2m-audio.o
> >  obj-$(CONFIG_VIDEO_VIMC) += vimc/
> >  obj-$(CONFIG_VIDEO_VIVID) += vivid/
> >  obj-$(CONFIG_VIDEO_VISL) += visl/
> > diff --git a/drivers/media/test-drivers/vim2m-audio.c b/drivers/media/test-drivers/vim2m-audio.c
> > new file mode 100644
> > index 000000000000..72806ada8628
> > --- /dev/null
> > +++ b/drivers/media/test-drivers/vim2m-audio.c
> > @@ -0,0 +1,799 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * A virtual v4l2-mem2mem example for audio device.
> > + */
> > +
> > +#include <linux/module.h>
> > +#include <linux/delay.h>
> > +#include <linux/fs.h>
> > +#include <linux/sched.h>
> > +#include <linux/slab.h>
> > +
> > +#include <linux/platform_device.h>
> > +#include <media/v4l2-mem2mem.h>
> > +#include <media/v4l2-device.h>
> > +#include <media/v4l2-ioctl.h>
> > +#include <media/v4l2-ctrls.h>
> > +#include <media/v4l2-event.h>
> > +#include <media/videobuf2-vmalloc.h>
> > +#include <sound/dmaengine_pcm.h>
> > +
> > +MODULE_DESCRIPTION("Virtual device for audio mem2mem testing");
> > +MODULE_LICENSE("GPL");
> > +
> > +static unsigned int debug;
> > +module_param(debug, uint, 0644);
> > +MODULE_PARM_DESC(debug, "debug level");
> > +
> > +#define MEM2MEM_NAME "vim2m-audio"
> > +
> > +#define dprintk(dev, lvl, fmt, arg...) \
> > +     v4l2_dbg(lvl, debug, &(dev)->v4l2_dev, "%s: " fmt, __func__, ## arg)
> > +
> > +#define SAMPLE_NUM 4096
> > +
> > +static void audm2m_dev_release(struct device *dev)
> > +{}
> > +
> > +static struct platform_device audm2m_pdev = {
> > +     .name           = MEM2MEM_NAME,
> > +     .dev.release    = audm2m_dev_release,
> > +};
> > +
> > +static u32 formats[] = {
> > +     V4L2_AUDIO_FMT_S16_LE,
> > +};
> > +
> > +#define NUM_FORMATS ARRAY_SIZE(formats)
> > +
> > +/* Per-queue, driver-specific private data */
> > +struct audm2m_q_data {
> > +     unsigned int            rate;
> > +     unsigned int            channels;
> > +     unsigned int            buffersize;
> > +     unsigned int            sequence;
> > +     u32                     fourcc;
> > +};
> > +
> > +enum {
> > +     V4L2_M2M_SRC = 0,
> > +     V4L2_M2M_DST = 1,
> > +};
> > +
> > +static snd_pcm_format_t find_format(u32 fourcc)
> > +{
> > +     snd_pcm_format_t fmt;
> > +     unsigned int k;
> > +
> > +     for (k = 0; k < NUM_FORMATS; k++) {
> > +             if (formats[k] == fourcc)
> > +                     break;
> > +     }
> > +
> > +     if (k == NUM_FORMATS)
> > +             return 0;
> > +
> > +     fmt = v4l2_fourcc_to_audfmt(formats[k]);
> > +
> > +     return fmt;
> > +}
> > +
> > +struct audm2m_dev {
> > +     struct v4l2_device      v4l2_dev;
> > +     struct video_device     vfd;
> > +
> > +     struct mutex            dev_mutex;
> > +
> > +     struct v4l2_m2m_dev     *m2m_dev;
> > +#ifdef CONFIG_MEDIA_CONTROLLER
> > +     struct media_device     mdev;
> > +#endif
> > +};
> > +
> > +struct audm2m_ctx {
> > +     struct v4l2_fh          fh;
> > +     struct v4l2_ctrl_handler        ctrl_handler;
> > +     struct audm2m_dev       *dev;
> > +
> > +     struct mutex            vb_mutex;
> > +
> > +     /* Source and destination queue data */
> > +     struct audm2m_q_data   q_data[2];
> > +};
> > +
> > +static inline struct audm2m_ctx *file2ctx(struct file *file)
> > +{
> > +     return container_of(file->private_data, struct audm2m_ctx, fh);
> > +}
> > +
> > +static struct audm2m_q_data *get_q_data(struct audm2m_ctx *ctx,
> > +                                     enum v4l2_buf_type type)
> > +{
> > +     if (type == V4L2_BUF_TYPE_AUDIO_OUTPUT)
> > +             return &ctx->q_data[V4L2_M2M_SRC];
> > +     return &ctx->q_data[V4L2_M2M_DST];
> > +}
> > +
> > +static const char *type_name(enum v4l2_buf_type type)
> > +{
> > +     if (type == V4L2_BUF_TYPE_AUDIO_OUTPUT)
> > +             return "Output";
> > +     return "Capture";
> > +}
> > +
> > +/*
> > + * mem2mem callbacks
> > + */
> > +
> > +/*
> > + * device_run() - prepares and starts the device
> > + */
> > +static void device_run(void *priv)
> > +{
> > +     struct audm2m_ctx *ctx = priv;
> > +     struct audm2m_dev *audm2m_dev;
> > +     struct vb2_v4l2_buffer *src_buf, *dst_buf;
> > +     struct audm2m_q_data *q_data_src, *q_data_dst;
> > +     int src_size, dst_size = 0;
> > +     short *src_addr, *dst_addr;
> > +     int i;
> > +
> > +     audm2m_dev = ctx->dev;
> > +
> > +     q_data_src = get_q_data(ctx, V4L2_BUF_TYPE_AUDIO_OUTPUT);
> > +     if (!q_data_src)
> > +             return;
> > +
> > +     q_data_dst = get_q_data(ctx, V4L2_BUF_TYPE_AUDIO_CAPTURE);
> > +     if (!q_data_dst)
> > +             return;
> > +
> > +     src_buf = v4l2_m2m_next_src_buf(ctx->fh.m2m_ctx);
> > +     dst_buf = v4l2_m2m_next_dst_buf(ctx->fh.m2m_ctx);
> > +     src_buf->sequence = q_data_src->sequence++;
> > +     dst_buf->sequence = q_data_dst->sequence++;
> > +     v4l2_m2m_buf_copy_metadata(src_buf, dst_buf, false);
> > +
> > +     /* Process the conversion */
> > +     src_size = vb2_get_plane_payload(&src_buf->vb2_buf, 0);
> > +
> > +     src_addr = vb2_plane_vaddr(&src_buf->vb2_buf, 0);
> > +     dst_addr = vb2_plane_vaddr(&dst_buf->vb2_buf, 0);
> > +
> > +     if (q_data_src->rate == q_data_dst->rate) {
> > +             memcpy(dst_addr, src_addr, src_size);
> > +             dst_size = src_size;
> > +     } else if (q_data_src->rate == 2 * q_data_dst->rate) {
> > +             /* 8k to 16k */
> > +             for (i = 0; i < src_size / 2; i++) {
> > +                     *dst_addr++ = *src_addr++;
> > +                     src_addr++;
> > +             }
> > +
> > +             dst_size = src_size / 2;
> > +     } else if (q_data_src->rate * 2 == q_data_dst->rate) {
> > +             /* 16k to 8k */
> > +             for (i = 0; i < src_size / 2; i++) {
> > +                     *dst_addr++ = *src_addr;
> > +                     *dst_addr++ = *src_addr++;
> > +             }
> > +
> > +             dst_size = src_size * 2;
> > +     }
> > +
> > +     vb2_set_plane_payload(&dst_buf->vb2_buf, 0, dst_size);
> > +
> > +     src_buf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
> > +     dst_buf = v4l2_m2m_dst_buf_remove(ctx->fh.m2m_ctx);
> > +
> > +     v4l2_m2m_buf_done(src_buf, VB2_BUF_STATE_DONE);
> > +     v4l2_m2m_buf_done(dst_buf, VB2_BUF_STATE_DONE);
> > +     v4l2_m2m_job_finish(audm2m_dev->m2m_dev, ctx->fh.m2m_ctx);
> > +}
> > +
> > +static int audm2m_querycap(struct file *file, void *priv,
> > +                        struct v4l2_capability *cap)
> > +{
> > +     strscpy(cap->driver, MEM2MEM_NAME, sizeof(cap->driver));
> > +     strscpy(cap->card, MEM2MEM_NAME, sizeof(cap->card));
> > +     snprintf(cap->bus_info, sizeof(cap->bus_info),
> > +              "platform:%s", MEM2MEM_NAME);
>
> You can drop this bus_info line, it's filled in for you.

I see there is a warning from v4l2-compliance test if this line is removed.

warn: v4l2-compliance.cpp(676): media bus_info 'platform:vim2m-audio'
differs from V4L2 bus_info 'platform:vim2m-audio.0'


Best regards
Shengjiu Wang

>
> > +
> > +     return 0;
> > +}
> > +
> > +static int enum_fmt(struct v4l2_fmtdesc *f)
> > +{
> > +     int i, num;
> > +
> > +     num = 0;
> > +
> > +     for (i = 0; i < NUM_FORMATS; ++i) {
> > +             if (num == f->index)
> > +                     break;
> > +             /*
> > +              * Correct type but haven't reached our index yet,
> > +              * just increment per-type index
> > +              */
> > +             ++num;
> > +     }
> > +
> > +     if (i < NUM_FORMATS) {
> > +             /* Format found */
> > +             f->pixelformat = formats[i];
> > +             return 0;
> > +     }
> > +
> > +     /* Format not found */
> > +     return -EINVAL;
> > +}
> > +
> > +static int audm2m_enum_fmt_audio_cap(struct file *file, void *priv,
> > +                                  struct v4l2_fmtdesc *f)
> > +{
> > +     return enum_fmt(f);
> > +}
> > +
> > +static int audm2m_enum_fmt_audio_out(struct file *file, void *priv,
> > +                                  struct v4l2_fmtdesc *f)
> > +{
> > +     return enum_fmt(f);
> > +}
> > +
> > +static int audm2m_g_fmt(struct audm2m_ctx *ctx, struct v4l2_format *f)
> > +{
> > +     struct vb2_queue *vq;
> > +     struct audm2m_q_data *q_data;
> > +
> > +     vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
> > +     if (!vq)
> > +             return -EINVAL;
> > +
> > +     q_data = get_q_data(ctx, f->type);
> > +     if (!q_data)
> > +             return -EINVAL;
> > +
> > +     f->fmt.audio.audioformat = q_data->fourcc;
> > +     f->fmt.audio.channels   = q_data->channels;
> > +     f->fmt.audio.buffersize = q_data->buffersize;
> > +
> > +     return 0;
> > +}
> > +
> > +static int audm2m_g_fmt_audio_out(struct file *file, void *priv,
> > +                               struct v4l2_format *f)
> > +{
> > +     return audm2m_g_fmt(file2ctx(file), f);
> > +}
> > +
> > +static int audm2m_g_fmt_audio_cap(struct file *file, void *priv,
> > +                               struct v4l2_format *f)
> > +{
> > +     return audm2m_g_fmt(file2ctx(file), f);
> > +}
> > +
> > +static int audm2m_try_fmt(struct v4l2_format *f, snd_pcm_format_t fmt)
> > +{
> > +     f->fmt.audio.channels = 1;
> > +     f->fmt.audio.buffersize = f->fmt.audio.channels *
> > +                               snd_pcm_format_physical_width(fmt) *
> > +                               SAMPLE_NUM;
> > +     return 0;
> > +}
> > +
> > +static int audm2m_try_fmt_audio_cap(struct file *file, void *priv,
> > +                                 struct v4l2_format *f)
> > +{
> > +     snd_pcm_format_t fmt;
> > +
> > +     fmt = find_format(f->fmt.audio.audioformat);
> > +     if (!fmt) {
> > +             f->fmt.audio.audioformat = formats[0];
> > +             fmt = find_format(f->fmt.audio.audioformat);
> > +     }
> > +
> > +     return audm2m_try_fmt(f, fmt);
> > +}
> > +
> > +static int audm2m_try_fmt_audio_out(struct file *file, void *priv,
> > +                                 struct v4l2_format *f)
> > +{
> > +     snd_pcm_format_t fmt;
> > +
> > +     fmt = find_format(f->fmt.audio.audioformat);
> > +     if (!fmt) {
> > +             f->fmt.audio.audioformat = formats[0];
> > +             fmt = find_format(f->fmt.audio.audioformat);
> > +     }
> > +
> > +     return audm2m_try_fmt(f, fmt);
> > +}
> > +
> > +static int audm2m_s_fmt(struct audm2m_ctx *ctx, struct v4l2_format *f)
> > +{
> > +     struct audm2m_q_data *q_data;
> > +     struct vb2_queue *vq;
> > +     snd_pcm_format_t fmt;
> > +
> > +     vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
> > +     if (!vq)
> > +             return -EINVAL;
> > +
> > +     q_data = get_q_data(ctx, f->type);
> > +     if (!q_data)
> > +             return -EINVAL;
> > +
> > +     if (vb2_is_busy(vq)) {
> > +             v4l2_err(&ctx->dev->v4l2_dev, "%s queue busy\n", __func__);
> > +             return -EBUSY;
> > +     }
> > +
> > +     q_data->fourcc  = f->fmt.audio.audioformat;
> > +     q_data->channels = f->fmt.audio.channels;
> > +
> > +     fmt = find_format(f->fmt.audio.audioformat);
> > +     q_data->buffersize = q_data->channels *
> > +                          snd_pcm_format_physical_width(fmt) *
> > +                          SAMPLE_NUM;
> > +
> > +     dprintk(ctx->dev, 1,
> > +             "Format for type %s: %d/%d, fmt: %c%c%c%c\n",
> > +             type_name(f->type), q_data->rate,
> > +             q_data->channels,
> > +             (q_data->fourcc & 0xff),
> > +             (q_data->fourcc >>  8) & 0xff,
> > +             (q_data->fourcc >> 16) & 0xff,
> > +             (q_data->fourcc >> 24) & 0xff);
> > +
> > +     return 0;
> > +}
> > +
> > +static int audm2m_s_fmt_audio_cap(struct file *file, void *priv,
> > +                               struct v4l2_format *f)
> > +{
> > +     int ret;
> > +
> > +     ret = audm2m_try_fmt_audio_cap(file, priv, f);
> > +     if (ret)
> > +             return ret;
> > +
> > +     return audm2m_s_fmt(file2ctx(file), f);
> > +}
> > +
> > +static int audm2m_s_fmt_audio_out(struct file *file, void *priv,
> > +                               struct v4l2_format *f)
> > +{
> > +     int ret;
> > +
> > +     ret = audm2m_try_fmt_audio_out(file, priv, f);
> > +     if (ret)
> > +             return ret;
> > +
> > +     return audm2m_s_fmt(file2ctx(file), f);
> > +}
> > +
> > +static const struct v4l2_ioctl_ops audm2m_ioctl_ops = {
> > +     .vidioc_querycap                = audm2m_querycap,
> > +
> > +     .vidioc_enum_fmt_audio_cap      = audm2m_enum_fmt_audio_cap,
> > +     .vidioc_g_fmt_audio_cap         = audm2m_g_fmt_audio_cap,
> > +     .vidioc_try_fmt_audio_cap       = audm2m_try_fmt_audio_cap,
> > +     .vidioc_s_fmt_audio_cap         = audm2m_s_fmt_audio_cap,
> > +
> > +     .vidioc_enum_fmt_audio_out      = audm2m_enum_fmt_audio_out,
> > +     .vidioc_g_fmt_audio_out         = audm2m_g_fmt_audio_out,
> > +     .vidioc_try_fmt_audio_out       = audm2m_try_fmt_audio_out,
> > +     .vidioc_s_fmt_audio_out         = audm2m_s_fmt_audio_out,
> > +
> > +     .vidioc_reqbufs                 = v4l2_m2m_ioctl_reqbufs,
> > +     .vidioc_querybuf                = v4l2_m2m_ioctl_querybuf,
> > +     .vidioc_qbuf                    = v4l2_m2m_ioctl_qbuf,
> > +     .vidioc_dqbuf                   = v4l2_m2m_ioctl_dqbuf,
> > +     .vidioc_prepare_buf             = v4l2_m2m_ioctl_prepare_buf,
> > +     .vidioc_create_bufs             = v4l2_m2m_ioctl_create_bufs,
> > +     .vidioc_expbuf                  = v4l2_m2m_ioctl_expbuf,
> > +
> > +     .vidioc_streamon                = v4l2_m2m_ioctl_streamon,
> > +     .vidioc_streamoff               = v4l2_m2m_ioctl_streamoff,
> > +
> > +     .vidioc_subscribe_event         = v4l2_ctrl_subscribe_event,
> > +     .vidioc_unsubscribe_event       = v4l2_event_unsubscribe,
> > +};
> > +
> > +/*
> > + * Queue operations
> > + */
> > +static int audm2m_queue_setup(struct vb2_queue *vq,
> > +                           unsigned int *nbuffers,
> > +                           unsigned int *nplanes,
> > +                           unsigned int sizes[],
> > +                           struct device *alloc_devs[])
> > +{
> > +     struct audm2m_ctx *ctx = vb2_get_drv_priv(vq);
> > +     struct audm2m_q_data *q_data;
> > +
> > +     q_data = get_q_data(ctx, vq->type);
> > +
> > +     if (*nplanes)
> > +             return sizes[0] < q_data->buffersize ? -EINVAL : 0;
> > +
> > +     *nplanes = 1;
> > +     sizes[0] = q_data->buffersize;
> > +
> > +     dprintk(ctx->dev, 1, "%s: get %d buffer(s) of size %d each.\n",
> > +             type_name(vq->type), *nplanes, sizes[0]);
> > +
> > +     return 0;
> > +}
> > +
> > +static void audm2m_buf_queue(struct vb2_buffer *vb)
> > +{
> > +     struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
> > +     struct audm2m_ctx *ctx = vb2_get_drv_priv(vb->vb2_queue);
> > +
> > +     v4l2_m2m_buf_queue(ctx->fh.m2m_ctx, vbuf);
> > +}
> > +
> > +static int audm2m_start_streaming(struct vb2_queue *q, unsigned int count)
> > +{
> > +     struct audm2m_ctx *ctx = vb2_get_drv_priv(q);
> > +     struct audm2m_q_data *q_data = get_q_data(ctx, q->type);
> > +
> > +     q_data->sequence = 0;
> > +     return 0;
> > +}
> > +
> > +static void audm2m_stop_streaming(struct vb2_queue *q)
> > +{
> > +     struct audm2m_ctx *ctx = vb2_get_drv_priv(q);
> > +     struct vb2_v4l2_buffer *vbuf;
> > +
> > +     for (;;) {
> > +             if (V4L2_TYPE_IS_OUTPUT(q->type))
> > +                     vbuf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
> > +             else
> > +                     vbuf = v4l2_m2m_dst_buf_remove(ctx->fh.m2m_ctx);
> > +             if (!vbuf)
> > +                     return;
> > +             v4l2_m2m_buf_done(vbuf, VB2_BUF_STATE_ERROR);
> > +     }
> > +}
> > +
> > +static const struct vb2_ops audm2m_qops = {
> > +     .queue_setup     = audm2m_queue_setup,
> > +     .buf_queue       = audm2m_buf_queue,
> > +     .start_streaming = audm2m_start_streaming,
> > +     .stop_streaming  = audm2m_stop_streaming,
> > +     .wait_prepare    = vb2_ops_wait_prepare,
> > +     .wait_finish     = vb2_ops_wait_finish,
> > +};
> > +
> > +static int queue_init(void *priv, struct vb2_queue *src_vq,
> > +                   struct vb2_queue *dst_vq)
> > +{
> > +     struct audm2m_ctx *ctx = priv;
> > +     int ret;
> > +
> > +     src_vq->type = V4L2_BUF_TYPE_AUDIO_OUTPUT;
> > +     src_vq->io_modes = VB2_MMAP | VB2_DMABUF;
> > +     src_vq->drv_priv = ctx;
> > +     src_vq->buf_struct_size = sizeof(struct v4l2_m2m_buffer);
> > +     src_vq->ops = &audm2m_qops;
> > +     src_vq->mem_ops = &vb2_vmalloc_memops;
> > +     src_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
> > +     src_vq->lock = &ctx->vb_mutex;
> > +     src_vq->min_buffers_needed = 1;
>
> Drop this, it's not needed.
>
> > +
> > +     ret = vb2_queue_init(src_vq);
> > +     if (ret)
> > +             return ret;
> > +
> > +     dst_vq->type = V4L2_BUF_TYPE_AUDIO_CAPTURE;
> > +     dst_vq->io_modes = VB2_MMAP | VB2_DMABUF;
> > +     dst_vq->drv_priv = ctx;
> > +     dst_vq->buf_struct_size = sizeof(struct v4l2_m2m_buffer);
> > +     dst_vq->ops = &audm2m_qops;
> > +     dst_vq->mem_ops = &vb2_vmalloc_memops;
> > +     dst_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
> > +     dst_vq->lock = &ctx->vb_mutex;
> > +     dst_vq->min_buffers_needed = 1;
>
> Ditto.
>
> > +
> > +     return vb2_queue_init(dst_vq);
> > +}
> > +
> > +static const s64 audm2m_rates[] = {
> > +     8000, 16000,
> > +};
> > +
> > +static int audm2m_op_s_ctrl(struct v4l2_ctrl *ctrl)
> > +{
> > +     struct audm2m_ctx *ctx =
> > +             container_of(ctrl->handler, struct audm2m_ctx, ctrl_handler);
> > +     int ret = 0;
> > +
> > +     switch (ctrl->id) {
> > +     case V4L2_CID_M2M_AUDIO_SOURCE_RATE:
> > +             ctx->q_data[V4L2_M2M_SRC].rate = ctrl->qmenu_int[ctrl->val];
> > +             break;
> > +     case V4L2_CID_M2M_AUDIO_DEST_RATE:
> > +             ctx->q_data[V4L2_M2M_DST].rate = ctrl->qmenu_int[ctrl->val];
> > +             break;
> > +     default:
> > +             ret = -EINVAL;
> > +             break;
> > +     }
> > +
> > +     return ret;
> > +}
> > +
> > +static const struct v4l2_ctrl_ops audm2m_ctrl_ops = {
> > +     .s_ctrl = audm2m_op_s_ctrl,
> > +};
> > +
> > +/*
> > + * File operations
> > + */
> > +static int audm2m_open(struct file *file)
> > +{
> > +     struct audm2m_dev *dev = video_drvdata(file);
> > +     struct audm2m_ctx *ctx = NULL;
> > +     snd_pcm_format_t fmt;
> > +     int width;
> > +     int rc = 0;
> > +
> > +     if (mutex_lock_interruptible(&dev->dev_mutex))
> > +             return -ERESTARTSYS;
> > +     ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
> > +     if (!ctx) {
> > +             rc = -ENOMEM;
> > +             goto open_unlock;
> > +     }
> > +
> > +     v4l2_fh_init(&ctx->fh, video_devdata(file));
> > +     file->private_data = &ctx->fh;
> > +     ctx->dev = dev;
> > +
> > +     ctx->q_data[V4L2_M2M_SRC].fourcc = formats[0];
> > +     ctx->q_data[V4L2_M2M_SRC].rate = 8000;
> > +     ctx->q_data[V4L2_M2M_SRC].channels = 1;
> > +
> > +     /* Fix to 4096 samples */
> > +     fmt = find_format(formats[0]);
> > +     width = snd_pcm_format_physical_width(fmt);
> > +     ctx->q_data[V4L2_M2M_SRC].buffersize = SAMPLE_NUM * width;
> > +     ctx->q_data[V4L2_M2M_DST] = ctx->q_data[V4L2_M2M_SRC];
> > +
> > +     ctx->fh.m2m_ctx = v4l2_m2m_ctx_init(dev->m2m_dev, ctx, &queue_init);
> > +
> > +     mutex_init(&ctx->vb_mutex);
> > +
> > +     if (IS_ERR(ctx->fh.m2m_ctx)) {
> > +             rc = PTR_ERR(ctx->fh.m2m_ctx);
> > +
> > +             v4l2_fh_exit(&ctx->fh);
> > +             kfree(ctx);
> > +             goto open_unlock;
> > +     }
> > +
> > +     v4l2_fh_add(&ctx->fh);
> > +
> > +     dprintk(dev, 1, "Created instance: %p, m2m_ctx: %p\n",
> > +             ctx, ctx->fh.m2m_ctx);
> > +
> > +     v4l2_ctrl_handler_init(&ctx->ctrl_handler, 2);
> > +
> > +     v4l2_ctrl_new_int_menu(&ctx->ctrl_handler, &audm2m_ctrl_ops,
> > +                            V4L2_CID_M2M_AUDIO_SOURCE_RATE,
> > +                            ARRAY_SIZE(audm2m_rates) - 1, 0, audm2m_rates);
> > +     v4l2_ctrl_new_int_menu(&ctx->ctrl_handler, &audm2m_ctrl_ops,
> > +                            V4L2_CID_M2M_AUDIO_DEST_RATE,
> > +                            ARRAY_SIZE(audm2m_rates) - 1, 0, audm2m_rates);
> > +
> > +     if (ctx->ctrl_handler.error) {
> > +             rc = ctx->ctrl_handler.error;
> > +             v4l2_ctrl_handler_free(&ctx->ctrl_handler);
> > +             goto err_ctrl_handler;
> > +     }
> > +
> > +     ctx->fh.ctrl_handler = &ctx->ctrl_handler;
> > +
> > +     mutex_unlock(&dev->dev_mutex);
> > +
> > +     return 0;
> > +
> > +err_ctrl_handler:
> > +     v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
> > +open_unlock:
> > +     mutex_unlock(&dev->dev_mutex);
> > +     return rc;
> > +}
> > +
> > +static int audm2m_release(struct file *file)
> > +{
> > +     struct audm2m_dev *dev = video_drvdata(file);
> > +     struct audm2m_ctx *ctx = file2ctx(file);
> > +
> > +     dprintk(dev, 1, "Releasing instance %p\n", ctx);
> > +
> > +     v4l2_ctrl_handler_free(&ctx->ctrl_handler);
> > +     v4l2_fh_del(&ctx->fh);
> > +     v4l2_fh_exit(&ctx->fh);
> > +     mutex_lock(&dev->dev_mutex);
> > +     v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
> > +     mutex_unlock(&dev->dev_mutex);
> > +     kfree(ctx);
> > +
> > +     return 0;
> > +}
> > +
> > +static void audm2m_device_release(struct video_device *vdev)
> > +{
> > +     struct audm2m_dev *dev = container_of(vdev, struct audm2m_dev, vfd);
> > +
> > +     v4l2_device_unregister(&dev->v4l2_dev);
> > +     v4l2_m2m_release(dev->m2m_dev);
> > +
> > +#ifdef CONFIG_MEDIA_CONTROLLER
> > +     media_device_cleanup(&dev->mdev);
> > +#endif
> > +     kfree(dev);
> > +}
> > +
> > +static const struct v4l2_file_operations audm2m_fops = {
> > +     .owner          = THIS_MODULE,
> > +     .open           = audm2m_open,
> > +     .release        = audm2m_release,
> > +     .poll           = v4l2_m2m_fop_poll,
> > +     .unlocked_ioctl = video_ioctl2,
> > +     .mmap           = v4l2_m2m_fop_mmap,
> > +};
> > +
> > +static const struct video_device audm2m_videodev = {
> > +     .name           = MEM2MEM_NAME,
> > +     .vfl_dir        = VFL_DIR_M2M,
> > +     .fops           = &audm2m_fops,
> > +     .ioctl_ops      = &audm2m_ioctl_ops,
> > +     .minor          = -1,
> > +     .release        = audm2m_device_release,
> > +     .device_caps    = V4L2_CAP_AUDIO_M2M | V4L2_CAP_STREAMING,
> > +};
> > +
> > +static const struct v4l2_m2m_ops m2m_ops = {
> > +     .device_run     = device_run,
> > +};
> > +
> > +static const struct media_device_ops audm2m_media_ops = {
> > +     .req_validate = vb2_request_validate,
> > +     .req_queue = v4l2_m2m_request_queue,
> > +};
> > +
> > +static int audm2m_probe(struct platform_device *pdev)
> > +{
> > +     struct audm2m_dev *dev;
> > +     struct video_device *vfd;
> > +     int ret;
> > +
> > +     dev = kzalloc(sizeof(*dev), GFP_KERNEL);
> > +     if (!dev)
> > +             return -ENOMEM;
> > +
> > +     ret = v4l2_device_register(&pdev->dev, &dev->v4l2_dev);
> > +     if (ret)
> > +             goto error_free;
> > +
> > +     mutex_init(&dev->dev_mutex);
> > +
> > +     dev->vfd = audm2m_videodev;
> > +     vfd = &dev->vfd;
> > +     vfd->lock = &dev->dev_mutex;
> > +     vfd->v4l2_dev = &dev->v4l2_dev;
> > +
> > +     video_set_drvdata(vfd, dev);
> > +     platform_set_drvdata(pdev, dev);
> > +
> > +     dev->m2m_dev = v4l2_m2m_init(&m2m_ops);
> > +     if (IS_ERR(dev->m2m_dev)) {
> > +             v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem device\n");
> > +             ret = PTR_ERR(dev->m2m_dev);
> > +             dev->m2m_dev = NULL;
> > +             goto error_dev;
> > +     }
> > +
> > +#ifdef CONFIG_MEDIA_CONTROLLER
> > +     dev->mdev.dev = &pdev->dev;
> > +     strscpy(dev->mdev.model, MEM2MEM_NAME, sizeof(dev->mdev.model));
> > +     snprintf(dev->mdev.bus_info, sizeof(dev->mdev.bus_info),
> > +              "platform:%s", MEM2MEM_NAME);
> > +     media_device_init(&dev->mdev);
> > +     dev->mdev.ops = &audm2m_media_ops;
> > +     dev->v4l2_dev.mdev = &dev->mdev;
> > +#endif
> > +
> > +     ret = video_register_device(vfd, VFL_TYPE_AUDIO, 0);
> > +     if (ret) {
> > +             v4l2_err(&dev->v4l2_dev, "Failed to register video device\n");
> > +             goto error_m2m;
> > +     }
> > +
> > +#ifdef CONFIG_MEDIA_CONTROLLER
> > +     ret = v4l2_m2m_register_media_controller(dev->m2m_dev, vfd,
> > +                                              MEDIA_ENT_F_PROC_AUDIO_RESAMPLER);
> > +     if (ret) {
> > +             v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem media controller\n");
> > +             goto error_v4l2;
> > +     }
> > +
> > +     ret = media_device_register(&dev->mdev);
> > +     if (ret) {
> > +             v4l2_err(&dev->v4l2_dev, "Failed to register mem2mem media device\n");
> > +             goto error_m2m_mc;
> > +     }
> > +#endif
> > +
> > +     v4l2_info(&dev->v4l2_dev,
> > +               "Device registered as /dev/v4l-audio%d\n", vfd->num);
> > +
> > +     return 0;
> > +
> > +#ifdef CONFIG_MEDIA_CONTROLLER
> > +error_m2m_mc:
> > +     v4l2_m2m_unregister_media_controller(dev->m2m_dev);
> > +#endif
> > +error_v4l2:
> > +     video_unregister_device(&dev->vfd);
> > +     /* audm2m_device_release called by video_unregister_device to release various objects */
> > +     return ret;
> > +error_m2m:
> > +     v4l2_m2m_release(dev->m2m_dev);
> > +error_dev:
> > +     v4l2_device_unregister(&dev->v4l2_dev);
> > +error_free:
> > +     kfree(dev);
> > +
> > +     return ret;
> > +}
> > +
> > +static void audm2m_remove(struct platform_device *pdev)
> > +{
> > +     struct audm2m_dev *dev = platform_get_drvdata(pdev);
> > +
> > +     v4l2_info(&dev->v4l2_dev, "Removing " MEM2MEM_NAME);
> > +
> > +#ifdef CONFIG_MEDIA_CONTROLLER
> > +     media_device_unregister(&dev->mdev);
> > +     v4l2_m2m_unregister_media_controller(dev->m2m_dev);
> > +#endif
> > +     video_unregister_device(&dev->vfd);
> > +}
> > +
> > +static struct platform_driver audm2m_pdrv = {
> > +     .probe          = audm2m_probe,
> > +     .remove_new     = audm2m_remove,
> > +     .driver         = {
> > +             .name   = MEM2MEM_NAME,
> > +     },
> > +};
> > +
> > +static void __exit audm2m_exit(void)
> > +{
> > +     platform_driver_unregister(&audm2m_pdrv);
> > +     platform_device_unregister(&audm2m_pdev);
> > +}
> > +
> > +static int __init audm2m_init(void)
> > +{
> > +     int ret;
> > +
> > +     ret = platform_device_register(&audm2m_pdev);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = platform_driver_register(&audm2m_pdrv);
> > +     if (ret)
> > +             platform_device_unregister(&audm2m_pdev);
> > +
> > +     return ret;
> > +}
> > +
> > +module_init(audm2m_init);
> > +module_exit(audm2m_exit);
>
> Regards,
>
>         Hans
Hans Verkuil Jan. 18, 2024, 7:56 a.m. UTC | #3
On 18/01/2024 07:13, Shengjiu Wang wrote:
> On Wed, Jan 17, 2024 at 6:32 PM Hans Verkuil <hverkuil@xs4all.nl> wrote:
>>
>> On 22/11/2023 08:23, Shengjiu Wang wrote:
>>> Audio memory to memory virtual driver use video memory to memory
>>> virtual driver vim2m.c as example. The main difference is
>>> device type is VFL_TYPE_AUDIO and device cap type is V4L2_CAP_AUDIO_M2M.
>>>
>>> The device_run function is a dummy function, which is simply
>>> copy the data from input buffer to output buffer.
>>>
>>> Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
>>> ---
>>>  drivers/media/test-drivers/Kconfig       |  11 +
>>>  drivers/media/test-drivers/Makefile      |   1 +
>>>  drivers/media/test-drivers/vim2m-audio.c | 799 +++++++++++++++++++++++
>>>  3 files changed, 811 insertions(+)
>>>  create mode 100644 drivers/media/test-drivers/vim2m-audio.c
>>>
>>> diff --git a/drivers/media/test-drivers/Kconfig b/drivers/media/test-drivers/Kconfig
>>> index 459b433e9fae..55f8af6ee4e2 100644
>>> --- a/drivers/media/test-drivers/Kconfig
>>> +++ b/drivers/media/test-drivers/Kconfig
>>> @@ -17,6 +17,17 @@ config VIDEO_VIM2M
>>>         This is a virtual test device for the memory-to-memory driver
>>>         framework.
>>>
>>> +config VIDEO_VIM2M_AUDIO
>>> +     tristate "Virtual Memory-to-Memory Driver For Audio"
>>> +     depends on VIDEO_DEV
>>> +     select VIDEOBUF2_VMALLOC
>>> +     select V4L2_MEM2MEM_DEV
>>> +     select MEDIA_CONTROLLER
>>> +     select MEDIA_CONTROLLER_REQUEST_API
>>
>> Drop this. This option has been removed.
>>
>>> +     help
>>> +       This is a virtual audio test device for the memory-to-memory driver
>>> +       framework.
>>> +
>>>  source "drivers/media/test-drivers/vicodec/Kconfig"
>>>  source "drivers/media/test-drivers/vimc/Kconfig"
>>>  source "drivers/media/test-drivers/vivid/Kconfig"
>>> diff --git a/drivers/media/test-drivers/Makefile b/drivers/media/test-drivers/Makefile
>>> index 740714a4584d..0c61c9ada3e1 100644
>>> --- a/drivers/media/test-drivers/Makefile
>>> +++ b/drivers/media/test-drivers/Makefile
>>> @@ -10,6 +10,7 @@ obj-$(CONFIG_DVB_VIDTV) += vidtv/
>>>
>>>  obj-$(CONFIG_VIDEO_VICODEC) += vicodec/
>>>  obj-$(CONFIG_VIDEO_VIM2M) += vim2m.o
>>> +obj-$(CONFIG_VIDEO_VIM2M_AUDIO) += vim2m-audio.o
>>>  obj-$(CONFIG_VIDEO_VIMC) += vimc/
>>>  obj-$(CONFIG_VIDEO_VIVID) += vivid/
>>>  obj-$(CONFIG_VIDEO_VISL) += visl/
>>> diff --git a/drivers/media/test-drivers/vim2m-audio.c b/drivers/media/test-drivers/vim2m-audio.c
>>> new file mode 100644
>>> index 000000000000..72806ada8628
>>> --- /dev/null
>>> +++ b/drivers/media/test-drivers/vim2m-audio.c
>>> @@ -0,0 +1,799 @@
>>> +// SPDX-License-Identifier: GPL-2.0+
>>> +/*
>>> + * A virtual v4l2-mem2mem example for audio device.
>>> + */
>>> +
>>> +#include <linux/module.h>
>>> +#include <linux/delay.h>
>>> +#include <linux/fs.h>
>>> +#include <linux/sched.h>
>>> +#include <linux/slab.h>
>>> +
>>> +#include <linux/platform_device.h>
>>> +#include <media/v4l2-mem2mem.h>
>>> +#include <media/v4l2-device.h>
>>> +#include <media/v4l2-ioctl.h>
>>> +#include <media/v4l2-ctrls.h>
>>> +#include <media/v4l2-event.h>
>>> +#include <media/videobuf2-vmalloc.h>
>>> +#include <sound/dmaengine_pcm.h>
>>> +
>>> +MODULE_DESCRIPTION("Virtual device for audio mem2mem testing");
>>> +MODULE_LICENSE("GPL");
>>> +
>>> +static unsigned int debug;
>>> +module_param(debug, uint, 0644);
>>> +MODULE_PARM_DESC(debug, "debug level");
>>> +
>>> +#define MEM2MEM_NAME "vim2m-audio"
>>> +
>>> +#define dprintk(dev, lvl, fmt, arg...) \
>>> +     v4l2_dbg(lvl, debug, &(dev)->v4l2_dev, "%s: " fmt, __func__, ## arg)
>>> +
>>> +#define SAMPLE_NUM 4096
>>> +
>>> +static void audm2m_dev_release(struct device *dev)
>>> +{}
>>> +
>>> +static struct platform_device audm2m_pdev = {
>>> +     .name           = MEM2MEM_NAME,
>>> +     .dev.release    = audm2m_dev_release,
>>> +};
>>> +
>>> +static u32 formats[] = {
>>> +     V4L2_AUDIO_FMT_S16_LE,
>>> +};
>>> +
>>> +#define NUM_FORMATS ARRAY_SIZE(formats)
>>> +
>>> +/* Per-queue, driver-specific private data */
>>> +struct audm2m_q_data {
>>> +     unsigned int            rate;
>>> +     unsigned int            channels;
>>> +     unsigned int            buffersize;
>>> +     unsigned int            sequence;
>>> +     u32                     fourcc;
>>> +};
>>> +
>>> +enum {
>>> +     V4L2_M2M_SRC = 0,
>>> +     V4L2_M2M_DST = 1,
>>> +};
>>> +
>>> +static snd_pcm_format_t find_format(u32 fourcc)
>>> +{
>>> +     snd_pcm_format_t fmt;
>>> +     unsigned int k;
>>> +
>>> +     for (k = 0; k < NUM_FORMATS; k++) {
>>> +             if (formats[k] == fourcc)
>>> +                     break;
>>> +     }
>>> +
>>> +     if (k == NUM_FORMATS)
>>> +             return 0;
>>> +
>>> +     fmt = v4l2_fourcc_to_audfmt(formats[k]);
>>> +
>>> +     return fmt;
>>> +}
>>> +
>>> +struct audm2m_dev {
>>> +     struct v4l2_device      v4l2_dev;
>>> +     struct video_device     vfd;
>>> +
>>> +     struct mutex            dev_mutex;
>>> +
>>> +     struct v4l2_m2m_dev     *m2m_dev;
>>> +#ifdef CONFIG_MEDIA_CONTROLLER
>>> +     struct media_device     mdev;
>>> +#endif
>>> +};
>>> +
>>> +struct audm2m_ctx {
>>> +     struct v4l2_fh          fh;
>>> +     struct v4l2_ctrl_handler        ctrl_handler;
>>> +     struct audm2m_dev       *dev;
>>> +
>>> +     struct mutex            vb_mutex;
>>> +
>>> +     /* Source and destination queue data */
>>> +     struct audm2m_q_data   q_data[2];
>>> +};
>>> +
>>> +static inline struct audm2m_ctx *file2ctx(struct file *file)
>>> +{
>>> +     return container_of(file->private_data, struct audm2m_ctx, fh);
>>> +}
>>> +
>>> +static struct audm2m_q_data *get_q_data(struct audm2m_ctx *ctx,
>>> +                                     enum v4l2_buf_type type)
>>> +{
>>> +     if (type == V4L2_BUF_TYPE_AUDIO_OUTPUT)
>>> +             return &ctx->q_data[V4L2_M2M_SRC];
>>> +     return &ctx->q_data[V4L2_M2M_DST];
>>> +}
>>> +
>>> +static const char *type_name(enum v4l2_buf_type type)
>>> +{
>>> +     if (type == V4L2_BUF_TYPE_AUDIO_OUTPUT)
>>> +             return "Output";
>>> +     return "Capture";
>>> +}
>>> +
>>> +/*
>>> + * mem2mem callbacks
>>> + */
>>> +
>>> +/*
>>> + * device_run() - prepares and starts the device
>>> + */
>>> +static void device_run(void *priv)
>>> +{
>>> +     struct audm2m_ctx *ctx = priv;
>>> +     struct audm2m_dev *audm2m_dev;
>>> +     struct vb2_v4l2_buffer *src_buf, *dst_buf;
>>> +     struct audm2m_q_data *q_data_src, *q_data_dst;
>>> +     int src_size, dst_size = 0;
>>> +     short *src_addr, *dst_addr;
>>> +     int i;
>>> +
>>> +     audm2m_dev = ctx->dev;
>>> +
>>> +     q_data_src = get_q_data(ctx, V4L2_BUF_TYPE_AUDIO_OUTPUT);
>>> +     if (!q_data_src)
>>> +             return;
>>> +
>>> +     q_data_dst = get_q_data(ctx, V4L2_BUF_TYPE_AUDIO_CAPTURE);
>>> +     if (!q_data_dst)
>>> +             return;
>>> +
>>> +     src_buf = v4l2_m2m_next_src_buf(ctx->fh.m2m_ctx);
>>> +     dst_buf = v4l2_m2m_next_dst_buf(ctx->fh.m2m_ctx);
>>> +     src_buf->sequence = q_data_src->sequence++;
>>> +     dst_buf->sequence = q_data_dst->sequence++;
>>> +     v4l2_m2m_buf_copy_metadata(src_buf, dst_buf, false);
>>> +
>>> +     /* Process the conversion */
>>> +     src_size = vb2_get_plane_payload(&src_buf->vb2_buf, 0);
>>> +
>>> +     src_addr = vb2_plane_vaddr(&src_buf->vb2_buf, 0);
>>> +     dst_addr = vb2_plane_vaddr(&dst_buf->vb2_buf, 0);
>>> +
>>> +     if (q_data_src->rate == q_data_dst->rate) {
>>> +             memcpy(dst_addr, src_addr, src_size);
>>> +             dst_size = src_size;
>>> +     } else if (q_data_src->rate == 2 * q_data_dst->rate) {
>>> +             /* 8k to 16k */
>>> +             for (i = 0; i < src_size / 2; i++) {
>>> +                     *dst_addr++ = *src_addr++;
>>> +                     src_addr++;
>>> +             }
>>> +
>>> +             dst_size = src_size / 2;
>>> +     } else if (q_data_src->rate * 2 == q_data_dst->rate) {
>>> +             /* 16k to 8k */
>>> +             for (i = 0; i < src_size / 2; i++) {
>>> +                     *dst_addr++ = *src_addr;
>>> +                     *dst_addr++ = *src_addr++;
>>> +             }
>>> +
>>> +             dst_size = src_size * 2;
>>> +     }
>>> +
>>> +     vb2_set_plane_payload(&dst_buf->vb2_buf, 0, dst_size);
>>> +
>>> +     src_buf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
>>> +     dst_buf = v4l2_m2m_dst_buf_remove(ctx->fh.m2m_ctx);
>>> +
>>> +     v4l2_m2m_buf_done(src_buf, VB2_BUF_STATE_DONE);
>>> +     v4l2_m2m_buf_done(dst_buf, VB2_BUF_STATE_DONE);
>>> +     v4l2_m2m_job_finish(audm2m_dev->m2m_dev, ctx->fh.m2m_ctx);
>>> +}
>>> +
>>> +static int audm2m_querycap(struct file *file, void *priv,
>>> +                        struct v4l2_capability *cap)
>>> +{
>>> +     strscpy(cap->driver, MEM2MEM_NAME, sizeof(cap->driver));
>>> +     strscpy(cap->card, MEM2MEM_NAME, sizeof(cap->card));
>>> +     snprintf(cap->bus_info, sizeof(cap->bus_info),
>>> +              "platform:%s", MEM2MEM_NAME);
>>
>> You can drop this bus_info line, it's filled in for you.
> 
> I see there is a warning from v4l2-compliance test if this line is removed.
> 
> warn: v4l2-compliance.cpp(676): media bus_info 'platform:vim2m-audio'
> differs from V4L2 bus_info 'platform:vim2m-audio.0'

You should also drop the line filling in the bus_info in the media device:

<snip>


>>> +static int audm2m_probe(struct platform_device *pdev)
>>> +{

<snip>

>>> +#ifdef CONFIG_MEDIA_CONTROLLER
>>> +     dev->mdev.dev = &pdev->dev;
>>> +     strscpy(dev->mdev.model, MEM2MEM_NAME, sizeof(dev->mdev.model));
>>> +     snprintf(dev->mdev.bus_info, sizeof(dev->mdev.bus_info),
>>> +              "platform:%s", MEM2MEM_NAME);

Drop this line.

>>> +     media_device_init(&dev->mdev);

This function will fill it in automatically as well, and with the same
name as querycap.

Regards,

	Hans

>>> +     dev->mdev.ops = &audm2m_media_ops;
>>> +     dev->v4l2_dev.mdev = &dev->mdev;
>>> +#endif
>>> +
>>> +     ret = video_register_device(vfd, VFL_TYPE_AUDIO, 0);
>>> +     if (ret) {
>>> +             v4l2_err(&dev->v4l2_dev, "Failed to register video device\n");
>>> +             goto error_m2m;
>>> +     }
>>> +
>>> +#ifdef CONFIG_MEDIA_CONTROLLER
>>> +     ret = v4l2_m2m_register_media_controller(dev->m2m_dev, vfd,
>>> +                                              MEDIA_ENT_F_PROC_AUDIO_RESAMPLER);
>>> +     if (ret) {
>>> +             v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem media controller\n");
>>> +             goto error_v4l2;
>>> +     }
>>> +
>>> +     ret = media_device_register(&dev->mdev);
>>> +     if (ret) {
>>> +             v4l2_err(&dev->v4l2_dev, "Failed to register mem2mem media device\n");
>>> +             goto error_m2m_mc;
>>> +     }
>>> +#endif
>>> +
>>> +     v4l2_info(&dev->v4l2_dev,
>>> +               "Device registered as /dev/v4l-audio%d\n", vfd->num);
>>> +
>>> +     return 0;
>>> +
>>> +#ifdef CONFIG_MEDIA_CONTROLLER
>>> +error_m2m_mc:
>>> +     v4l2_m2m_unregister_media_controller(dev->m2m_dev);
>>> +#endif
>>> +error_v4l2:
>>> +     video_unregister_device(&dev->vfd);
>>> +     /* audm2m_device_release called by video_unregister_device to release various objects */
>>> +     return ret;
>>> +error_m2m:
>>> +     v4l2_m2m_release(dev->m2m_dev);
>>> +error_dev:
>>> +     v4l2_device_unregister(&dev->v4l2_dev);
>>> +error_free:
>>> +     kfree(dev);
>>> +
>>> +     return ret;
>>> +}
>>> +
>>> +static void audm2m_remove(struct platform_device *pdev)
>>> +{
>>> +     struct audm2m_dev *dev = platform_get_drvdata(pdev);
>>> +
>>> +     v4l2_info(&dev->v4l2_dev, "Removing " MEM2MEM_NAME);
>>> +
>>> +#ifdef CONFIG_MEDIA_CONTROLLER
>>> +     media_device_unregister(&dev->mdev);
>>> +     v4l2_m2m_unregister_media_controller(dev->m2m_dev);
>>> +#endif
>>> +     video_unregister_device(&dev->vfd);
>>> +}
>>> +
>>> +static struct platform_driver audm2m_pdrv = {
>>> +     .probe          = audm2m_probe,
>>> +     .remove_new     = audm2m_remove,
>>> +     .driver         = {
>>> +             .name   = MEM2MEM_NAME,
>>> +     },
>>> +};
>>> +
>>> +static void __exit audm2m_exit(void)
>>> +{
>>> +     platform_driver_unregister(&audm2m_pdrv);
>>> +     platform_device_unregister(&audm2m_pdev);
>>> +}
>>> +
>>> +static int __init audm2m_init(void)
>>> +{
>>> +     int ret;
>>> +
>>> +     ret = platform_device_register(&audm2m_pdev);
>>> +     if (ret)
>>> +             return ret;
>>> +
>>> +     ret = platform_driver_register(&audm2m_pdrv);
>>> +     if (ret)
>>> +             platform_device_unregister(&audm2m_pdev);
>>> +
>>> +     return ret;
>>> +}
>>> +
>>> +module_init(audm2m_init);
>>> +module_exit(audm2m_exit);
>>
>> Regards,
>>
>>         Hans
Shengjiu Wang Jan. 18, 2024, 8:36 a.m. UTC | #4
On Thu, Jan 18, 2024 at 3:56 PM Hans Verkuil <hverkuil@xs4all.nl> wrote:
>
> On 18/01/2024 07:13, Shengjiu Wang wrote:
> > On Wed, Jan 17, 2024 at 6:32 PM Hans Verkuil <hverkuil@xs4all.nl> wrote:
> >>
> >> On 22/11/2023 08:23, Shengjiu Wang wrote:
> >>> Audio memory to memory virtual driver use video memory to memory
> >>> virtual driver vim2m.c as example. The main difference is
> >>> device type is VFL_TYPE_AUDIO and device cap type is V4L2_CAP_AUDIO_M2M.
> >>>
> >>> The device_run function is a dummy function, which is simply
> >>> copy the data from input buffer to output buffer.
> >>>
> >>> Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
> >>> ---
> >>>  drivers/media/test-drivers/Kconfig       |  11 +
> >>>  drivers/media/test-drivers/Makefile      |   1 +
> >>>  drivers/media/test-drivers/vim2m-audio.c | 799 +++++++++++++++++++++++
> >>>  3 files changed, 811 insertions(+)
> >>>  create mode 100644 drivers/media/test-drivers/vim2m-audio.c
> >>>
> >>> diff --git a/drivers/media/test-drivers/Kconfig b/drivers/media/test-drivers/Kconfig
> >>> index 459b433e9fae..55f8af6ee4e2 100644
> >>> --- a/drivers/media/test-drivers/Kconfig
> >>> +++ b/drivers/media/test-drivers/Kconfig
> >>> @@ -17,6 +17,17 @@ config VIDEO_VIM2M
> >>>         This is a virtual test device for the memory-to-memory driver
> >>>         framework.
> >>>
> >>> +config VIDEO_VIM2M_AUDIO
> >>> +     tristate "Virtual Memory-to-Memory Driver For Audio"
> >>> +     depends on VIDEO_DEV
> >>> +     select VIDEOBUF2_VMALLOC
> >>> +     select V4L2_MEM2MEM_DEV
> >>> +     select MEDIA_CONTROLLER
> >>> +     select MEDIA_CONTROLLER_REQUEST_API
> >>
> >> Drop this. This option has been removed.
> >>
> >>> +     help
> >>> +       This is a virtual audio test device for the memory-to-memory driver
> >>> +       framework.
> >>> +
> >>>  source "drivers/media/test-drivers/vicodec/Kconfig"
> >>>  source "drivers/media/test-drivers/vimc/Kconfig"
> >>>  source "drivers/media/test-drivers/vivid/Kconfig"
> >>> diff --git a/drivers/media/test-drivers/Makefile b/drivers/media/test-drivers/Makefile
> >>> index 740714a4584d..0c61c9ada3e1 100644
> >>> --- a/drivers/media/test-drivers/Makefile
> >>> +++ b/drivers/media/test-drivers/Makefile
> >>> @@ -10,6 +10,7 @@ obj-$(CONFIG_DVB_VIDTV) += vidtv/
> >>>
> >>>  obj-$(CONFIG_VIDEO_VICODEC) += vicodec/
> >>>  obj-$(CONFIG_VIDEO_VIM2M) += vim2m.o
> >>> +obj-$(CONFIG_VIDEO_VIM2M_AUDIO) += vim2m-audio.o
> >>>  obj-$(CONFIG_VIDEO_VIMC) += vimc/
> >>>  obj-$(CONFIG_VIDEO_VIVID) += vivid/
> >>>  obj-$(CONFIG_VIDEO_VISL) += visl/
> >>> diff --git a/drivers/media/test-drivers/vim2m-audio.c b/drivers/media/test-drivers/vim2m-audio.c
> >>> new file mode 100644
> >>> index 000000000000..72806ada8628
> >>> --- /dev/null
> >>> +++ b/drivers/media/test-drivers/vim2m-audio.c
> >>> @@ -0,0 +1,799 @@
> >>> +// SPDX-License-Identifier: GPL-2.0+
> >>> +/*
> >>> + * A virtual v4l2-mem2mem example for audio device.
> >>> + */
> >>> +
> >>> +#include <linux/module.h>
> >>> +#include <linux/delay.h>
> >>> +#include <linux/fs.h>
> >>> +#include <linux/sched.h>
> >>> +#include <linux/slab.h>
> >>> +
> >>> +#include <linux/platform_device.h>
> >>> +#include <media/v4l2-mem2mem.h>
> >>> +#include <media/v4l2-device.h>
> >>> +#include <media/v4l2-ioctl.h>
> >>> +#include <media/v4l2-ctrls.h>
> >>> +#include <media/v4l2-event.h>
> >>> +#include <media/videobuf2-vmalloc.h>
> >>> +#include <sound/dmaengine_pcm.h>
> >>> +
> >>> +MODULE_DESCRIPTION("Virtual device for audio mem2mem testing");
> >>> +MODULE_LICENSE("GPL");
> >>> +
> >>> +static unsigned int debug;
> >>> +module_param(debug, uint, 0644);
> >>> +MODULE_PARM_DESC(debug, "debug level");
> >>> +
> >>> +#define MEM2MEM_NAME "vim2m-audio"
> >>> +
> >>> +#define dprintk(dev, lvl, fmt, arg...) \
> >>> +     v4l2_dbg(lvl, debug, &(dev)->v4l2_dev, "%s: " fmt, __func__, ## arg)
> >>> +
> >>> +#define SAMPLE_NUM 4096
> >>> +
> >>> +static void audm2m_dev_release(struct device *dev)
> >>> +{}
> >>> +
> >>> +static struct platform_device audm2m_pdev = {
> >>> +     .name           = MEM2MEM_NAME,
> >>> +     .dev.release    = audm2m_dev_release,
> >>> +};
> >>> +
> >>> +static u32 formats[] = {
> >>> +     V4L2_AUDIO_FMT_S16_LE,
> >>> +};
> >>> +
> >>> +#define NUM_FORMATS ARRAY_SIZE(formats)
> >>> +
> >>> +/* Per-queue, driver-specific private data */
> >>> +struct audm2m_q_data {
> >>> +     unsigned int            rate;
> >>> +     unsigned int            channels;
> >>> +     unsigned int            buffersize;
> >>> +     unsigned int            sequence;
> >>> +     u32                     fourcc;
> >>> +};
> >>> +
> >>> +enum {
> >>> +     V4L2_M2M_SRC = 0,
> >>> +     V4L2_M2M_DST = 1,
> >>> +};
> >>> +
> >>> +static snd_pcm_format_t find_format(u32 fourcc)
> >>> +{
> >>> +     snd_pcm_format_t fmt;
> >>> +     unsigned int k;
> >>> +
> >>> +     for (k = 0; k < NUM_FORMATS; k++) {
> >>> +             if (formats[k] == fourcc)
> >>> +                     break;
> >>> +     }
> >>> +
> >>> +     if (k == NUM_FORMATS)
> >>> +             return 0;
> >>> +
> >>> +     fmt = v4l2_fourcc_to_audfmt(formats[k]);
> >>> +
> >>> +     return fmt;
> >>> +}
> >>> +
> >>> +struct audm2m_dev {
> >>> +     struct v4l2_device      v4l2_dev;
> >>> +     struct video_device     vfd;
> >>> +
> >>> +     struct mutex            dev_mutex;
> >>> +
> >>> +     struct v4l2_m2m_dev     *m2m_dev;
> >>> +#ifdef CONFIG_MEDIA_CONTROLLER
> >>> +     struct media_device     mdev;
> >>> +#endif
> >>> +};
> >>> +
> >>> +struct audm2m_ctx {
> >>> +     struct v4l2_fh          fh;
> >>> +     struct v4l2_ctrl_handler        ctrl_handler;
> >>> +     struct audm2m_dev       *dev;
> >>> +
> >>> +     struct mutex            vb_mutex;
> >>> +
> >>> +     /* Source and destination queue data */
> >>> +     struct audm2m_q_data   q_data[2];
> >>> +};
> >>> +
> >>> +static inline struct audm2m_ctx *file2ctx(struct file *file)
> >>> +{
> >>> +     return container_of(file->private_data, struct audm2m_ctx, fh);
> >>> +}
> >>> +
> >>> +static struct audm2m_q_data *get_q_data(struct audm2m_ctx *ctx,
> >>> +                                     enum v4l2_buf_type type)
> >>> +{
> >>> +     if (type == V4L2_BUF_TYPE_AUDIO_OUTPUT)
> >>> +             return &ctx->q_data[V4L2_M2M_SRC];
> >>> +     return &ctx->q_data[V4L2_M2M_DST];
> >>> +}
> >>> +
> >>> +static const char *type_name(enum v4l2_buf_type type)
> >>> +{
> >>> +     if (type == V4L2_BUF_TYPE_AUDIO_OUTPUT)
> >>> +             return "Output";
> >>> +     return "Capture";
> >>> +}
> >>> +
> >>> +/*
> >>> + * mem2mem callbacks
> >>> + */
> >>> +
> >>> +/*
> >>> + * device_run() - prepares and starts the device
> >>> + */
> >>> +static void device_run(void *priv)
> >>> +{
> >>> +     struct audm2m_ctx *ctx = priv;
> >>> +     struct audm2m_dev *audm2m_dev;
> >>> +     struct vb2_v4l2_buffer *src_buf, *dst_buf;
> >>> +     struct audm2m_q_data *q_data_src, *q_data_dst;
> >>> +     int src_size, dst_size = 0;
> >>> +     short *src_addr, *dst_addr;
> >>> +     int i;
> >>> +
> >>> +     audm2m_dev = ctx->dev;
> >>> +
> >>> +     q_data_src = get_q_data(ctx, V4L2_BUF_TYPE_AUDIO_OUTPUT);
> >>> +     if (!q_data_src)
> >>> +             return;
> >>> +
> >>> +     q_data_dst = get_q_data(ctx, V4L2_BUF_TYPE_AUDIO_CAPTURE);
> >>> +     if (!q_data_dst)
> >>> +             return;
> >>> +
> >>> +     src_buf = v4l2_m2m_next_src_buf(ctx->fh.m2m_ctx);
> >>> +     dst_buf = v4l2_m2m_next_dst_buf(ctx->fh.m2m_ctx);
> >>> +     src_buf->sequence = q_data_src->sequence++;
> >>> +     dst_buf->sequence = q_data_dst->sequence++;
> >>> +     v4l2_m2m_buf_copy_metadata(src_buf, dst_buf, false);
> >>> +
> >>> +     /* Process the conversion */
> >>> +     src_size = vb2_get_plane_payload(&src_buf->vb2_buf, 0);
> >>> +
> >>> +     src_addr = vb2_plane_vaddr(&src_buf->vb2_buf, 0);
> >>> +     dst_addr = vb2_plane_vaddr(&dst_buf->vb2_buf, 0);
> >>> +
> >>> +     if (q_data_src->rate == q_data_dst->rate) {
> >>> +             memcpy(dst_addr, src_addr, src_size);
> >>> +             dst_size = src_size;
> >>> +     } else if (q_data_src->rate == 2 * q_data_dst->rate) {
> >>> +             /* 8k to 16k */
> >>> +             for (i = 0; i < src_size / 2; i++) {
> >>> +                     *dst_addr++ = *src_addr++;
> >>> +                     src_addr++;
> >>> +             }
> >>> +
> >>> +             dst_size = src_size / 2;
> >>> +     } else if (q_data_src->rate * 2 == q_data_dst->rate) {
> >>> +             /* 16k to 8k */
> >>> +             for (i = 0; i < src_size / 2; i++) {
> >>> +                     *dst_addr++ = *src_addr;
> >>> +                     *dst_addr++ = *src_addr++;
> >>> +             }
> >>> +
> >>> +             dst_size = src_size * 2;
> >>> +     }
> >>> +
> >>> +     vb2_set_plane_payload(&dst_buf->vb2_buf, 0, dst_size);
> >>> +
> >>> +     src_buf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
> >>> +     dst_buf = v4l2_m2m_dst_buf_remove(ctx->fh.m2m_ctx);
> >>> +
> >>> +     v4l2_m2m_buf_done(src_buf, VB2_BUF_STATE_DONE);
> >>> +     v4l2_m2m_buf_done(dst_buf, VB2_BUF_STATE_DONE);
> >>> +     v4l2_m2m_job_finish(audm2m_dev->m2m_dev, ctx->fh.m2m_ctx);
> >>> +}
> >>> +
> >>> +static int audm2m_querycap(struct file *file, void *priv,
> >>> +                        struct v4l2_capability *cap)
> >>> +{
> >>> +     strscpy(cap->driver, MEM2MEM_NAME, sizeof(cap->driver));
> >>> +     strscpy(cap->card, MEM2MEM_NAME, sizeof(cap->card));
> >>> +     snprintf(cap->bus_info, sizeof(cap->bus_info),
> >>> +              "platform:%s", MEM2MEM_NAME);
> >>
> >> You can drop this bus_info line, it's filled in for you.
> >
> > I see there is a warning from v4l2-compliance test if this line is removed.
> >
> > warn: v4l2-compliance.cpp(676): media bus_info 'platform:vim2m-audio'
> > differs from V4L2 bus_info 'platform:vim2m-audio.0'
>
> You should also drop the line filling in the bus_info in the media device:
>
> <snip>
>
>
> >>> +static int audm2m_probe(struct platform_device *pdev)
> >>> +{
>
> <snip>
>
> >>> +#ifdef CONFIG_MEDIA_CONTROLLER
> >>> +     dev->mdev.dev = &pdev->dev;
> >>> +     strscpy(dev->mdev.model, MEM2MEM_NAME, sizeof(dev->mdev.model));
> >>> +     snprintf(dev->mdev.bus_info, sizeof(dev->mdev.bus_info),
> >>> +              "platform:%s", MEM2MEM_NAME);
>
> Drop this line.
>
> >>> +     media_device_init(&dev->mdev);
>
> This function will fill it in automatically as well, and with the same
> name as querycap.
>

Got it. thanks!

Best regards
Shengjiu Wang

> Regards,
>
>         Hans
>
> >>> +     dev->mdev.ops = &audm2m_media_ops;
> >>> +     dev->v4l2_dev.mdev = &dev->mdev;
> >>> +#endif
> >>> +
> >>> +     ret = video_register_device(vfd, VFL_TYPE_AUDIO, 0);
> >>> +     if (ret) {
> >>> +             v4l2_err(&dev->v4l2_dev, "Failed to register video device\n");
> >>> +             goto error_m2m;
> >>> +     }
> >>> +
> >>> +#ifdef CONFIG_MEDIA_CONTROLLER
> >>> +     ret = v4l2_m2m_register_media_controller(dev->m2m_dev, vfd,
> >>> +                                              MEDIA_ENT_F_PROC_AUDIO_RESAMPLER);
> >>> +     if (ret) {
> >>> +             v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem media controller\n");
> >>> +             goto error_v4l2;
> >>> +     }
> >>> +
> >>> +     ret = media_device_register(&dev->mdev);
> >>> +     if (ret) {
> >>> +             v4l2_err(&dev->v4l2_dev, "Failed to register mem2mem media device\n");
> >>> +             goto error_m2m_mc;
> >>> +     }
> >>> +#endif
> >>> +
> >>> +     v4l2_info(&dev->v4l2_dev,
> >>> +               "Device registered as /dev/v4l-audio%d\n", vfd->num);
> >>> +
> >>> +     return 0;
> >>> +
> >>> +#ifdef CONFIG_MEDIA_CONTROLLER
> >>> +error_m2m_mc:
> >>> +     v4l2_m2m_unregister_media_controller(dev->m2m_dev);
> >>> +#endif
> >>> +error_v4l2:
> >>> +     video_unregister_device(&dev->vfd);
> >>> +     /* audm2m_device_release called by video_unregister_device to release various objects */
> >>> +     return ret;
> >>> +error_m2m:
> >>> +     v4l2_m2m_release(dev->m2m_dev);
> >>> +error_dev:
> >>> +     v4l2_device_unregister(&dev->v4l2_dev);
> >>> +error_free:
> >>> +     kfree(dev);
> >>> +
> >>> +     return ret;
> >>> +}
> >>> +
> >>> +static void audm2m_remove(struct platform_device *pdev)
> >>> +{
> >>> +     struct audm2m_dev *dev = platform_get_drvdata(pdev);
> >>> +
> >>> +     v4l2_info(&dev->v4l2_dev, "Removing " MEM2MEM_NAME);
> >>> +
> >>> +#ifdef CONFIG_MEDIA_CONTROLLER
> >>> +     media_device_unregister(&dev->mdev);
> >>> +     v4l2_m2m_unregister_media_controller(dev->m2m_dev);
> >>> +#endif
> >>> +     video_unregister_device(&dev->vfd);
> >>> +}
> >>> +
> >>> +static struct platform_driver audm2m_pdrv = {
> >>> +     .probe          = audm2m_probe,
> >>> +     .remove_new     = audm2m_remove,
> >>> +     .driver         = {
> >>> +             .name   = MEM2MEM_NAME,
> >>> +     },
> >>> +};
> >>> +
> >>> +static void __exit audm2m_exit(void)
> >>> +{
> >>> +     platform_driver_unregister(&audm2m_pdrv);
> >>> +     platform_device_unregister(&audm2m_pdev);
> >>> +}
> >>> +
> >>> +static int __init audm2m_init(void)
> >>> +{
> >>> +     int ret;
> >>> +
> >>> +     ret = platform_device_register(&audm2m_pdev);
> >>> +     if (ret)
> >>> +             return ret;
> >>> +
> >>> +     ret = platform_driver_register(&audm2m_pdrv);
> >>> +     if (ret)
> >>> +             platform_device_unregister(&audm2m_pdev);
> >>> +
> >>> +     return ret;
> >>> +}
> >>> +
> >>> +module_init(audm2m_init);
> >>> +module_exit(audm2m_exit);
> >>
> >> Regards,
> >>
> >>         Hans
>
diff mbox series

Patch

diff --git a/drivers/media/test-drivers/Kconfig b/drivers/media/test-drivers/Kconfig
index 459b433e9fae..55f8af6ee4e2 100644
--- a/drivers/media/test-drivers/Kconfig
+++ b/drivers/media/test-drivers/Kconfig
@@ -17,6 +17,17 @@  config VIDEO_VIM2M
 	  This is a virtual test device for the memory-to-memory driver
 	  framework.
 
+config VIDEO_VIM2M_AUDIO
+	tristate "Virtual Memory-to-Memory Driver For Audio"
+	depends on VIDEO_DEV
+	select VIDEOBUF2_VMALLOC
+	select V4L2_MEM2MEM_DEV
+	select MEDIA_CONTROLLER
+	select MEDIA_CONTROLLER_REQUEST_API
+	help
+	  This is a virtual audio test device for the memory-to-memory driver
+	  framework.
+
 source "drivers/media/test-drivers/vicodec/Kconfig"
 source "drivers/media/test-drivers/vimc/Kconfig"
 source "drivers/media/test-drivers/vivid/Kconfig"
diff --git a/drivers/media/test-drivers/Makefile b/drivers/media/test-drivers/Makefile
index 740714a4584d..0c61c9ada3e1 100644
--- a/drivers/media/test-drivers/Makefile
+++ b/drivers/media/test-drivers/Makefile
@@ -10,6 +10,7 @@  obj-$(CONFIG_DVB_VIDTV) += vidtv/
 
 obj-$(CONFIG_VIDEO_VICODEC) += vicodec/
 obj-$(CONFIG_VIDEO_VIM2M) += vim2m.o
+obj-$(CONFIG_VIDEO_VIM2M_AUDIO) += vim2m-audio.o
 obj-$(CONFIG_VIDEO_VIMC) += vimc/
 obj-$(CONFIG_VIDEO_VIVID) += vivid/
 obj-$(CONFIG_VIDEO_VISL) += visl/
diff --git a/drivers/media/test-drivers/vim2m-audio.c b/drivers/media/test-drivers/vim2m-audio.c
new file mode 100644
index 000000000000..72806ada8628
--- /dev/null
+++ b/drivers/media/test-drivers/vim2m-audio.c
@@ -0,0 +1,799 @@ 
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * A virtual v4l2-mem2mem example for audio device.
+ */
+
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+
+#include <linux/platform_device.h>
+#include <media/v4l2-mem2mem.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-ioctl.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-event.h>
+#include <media/videobuf2-vmalloc.h>
+#include <sound/dmaengine_pcm.h>
+
+MODULE_DESCRIPTION("Virtual device for audio mem2mem testing");
+MODULE_LICENSE("GPL");
+
+static unsigned int debug;
+module_param(debug, uint, 0644);
+MODULE_PARM_DESC(debug, "debug level");
+
+#define MEM2MEM_NAME "vim2m-audio"
+
+#define dprintk(dev, lvl, fmt, arg...) \
+	v4l2_dbg(lvl, debug, &(dev)->v4l2_dev, "%s: " fmt, __func__, ## arg)
+
+#define SAMPLE_NUM 4096
+
+static void audm2m_dev_release(struct device *dev)
+{}
+
+static struct platform_device audm2m_pdev = {
+	.name		= MEM2MEM_NAME,
+	.dev.release	= audm2m_dev_release,
+};
+
+static u32 formats[] = {
+	V4L2_AUDIO_FMT_S16_LE,
+};
+
+#define NUM_FORMATS ARRAY_SIZE(formats)
+
+/* Per-queue, driver-specific private data */
+struct audm2m_q_data {
+	unsigned int		rate;
+	unsigned int		channels;
+	unsigned int		buffersize;
+	unsigned int		sequence;
+	u32			fourcc;
+};
+
+enum {
+	V4L2_M2M_SRC = 0,
+	V4L2_M2M_DST = 1,
+};
+
+static snd_pcm_format_t find_format(u32 fourcc)
+{
+	snd_pcm_format_t fmt;
+	unsigned int k;
+
+	for (k = 0; k < NUM_FORMATS; k++) {
+		if (formats[k] == fourcc)
+			break;
+	}
+
+	if (k == NUM_FORMATS)
+		return 0;
+
+	fmt = v4l2_fourcc_to_audfmt(formats[k]);
+
+	return fmt;
+}
+
+struct audm2m_dev {
+	struct v4l2_device	v4l2_dev;
+	struct video_device	vfd;
+
+	struct mutex		dev_mutex;
+
+	struct v4l2_m2m_dev	*m2m_dev;
+#ifdef CONFIG_MEDIA_CONTROLLER
+	struct media_device	mdev;
+#endif
+};
+
+struct audm2m_ctx {
+	struct v4l2_fh		fh;
+	struct v4l2_ctrl_handler	ctrl_handler;
+	struct audm2m_dev	*dev;
+
+	struct mutex		vb_mutex;
+
+	/* Source and destination queue data */
+	struct audm2m_q_data   q_data[2];
+};
+
+static inline struct audm2m_ctx *file2ctx(struct file *file)
+{
+	return container_of(file->private_data, struct audm2m_ctx, fh);
+}
+
+static struct audm2m_q_data *get_q_data(struct audm2m_ctx *ctx,
+					enum v4l2_buf_type type)
+{
+	if (type == V4L2_BUF_TYPE_AUDIO_OUTPUT)
+		return &ctx->q_data[V4L2_M2M_SRC];
+	return &ctx->q_data[V4L2_M2M_DST];
+}
+
+static const char *type_name(enum v4l2_buf_type type)
+{
+	if (type == V4L2_BUF_TYPE_AUDIO_OUTPUT)
+		return "Output";
+	return "Capture";
+}
+
+/*
+ * mem2mem callbacks
+ */
+
+/*
+ * device_run() - prepares and starts the device
+ */
+static void device_run(void *priv)
+{
+	struct audm2m_ctx *ctx = priv;
+	struct audm2m_dev *audm2m_dev;
+	struct vb2_v4l2_buffer *src_buf, *dst_buf;
+	struct audm2m_q_data *q_data_src, *q_data_dst;
+	int src_size, dst_size = 0;
+	short *src_addr, *dst_addr;
+	int i;
+
+	audm2m_dev = ctx->dev;
+
+	q_data_src = get_q_data(ctx, V4L2_BUF_TYPE_AUDIO_OUTPUT);
+	if (!q_data_src)
+		return;
+
+	q_data_dst = get_q_data(ctx, V4L2_BUF_TYPE_AUDIO_CAPTURE);
+	if (!q_data_dst)
+		return;
+
+	src_buf = v4l2_m2m_next_src_buf(ctx->fh.m2m_ctx);
+	dst_buf = v4l2_m2m_next_dst_buf(ctx->fh.m2m_ctx);
+	src_buf->sequence = q_data_src->sequence++;
+	dst_buf->sequence = q_data_dst->sequence++;
+	v4l2_m2m_buf_copy_metadata(src_buf, dst_buf, false);
+
+	/* Process the conversion */
+	src_size = vb2_get_plane_payload(&src_buf->vb2_buf, 0);
+
+	src_addr = vb2_plane_vaddr(&src_buf->vb2_buf, 0);
+	dst_addr = vb2_plane_vaddr(&dst_buf->vb2_buf, 0);
+
+	if (q_data_src->rate == q_data_dst->rate) {
+		memcpy(dst_addr, src_addr, src_size);
+		dst_size = src_size;
+	} else if (q_data_src->rate == 2 * q_data_dst->rate) {
+		/* 8k to 16k */
+		for (i = 0; i < src_size / 2; i++) {
+			*dst_addr++ = *src_addr++;
+			src_addr++;
+		}
+
+		dst_size = src_size / 2;
+	} else if (q_data_src->rate * 2 == q_data_dst->rate) {
+		/* 16k to 8k */
+		for (i = 0; i < src_size / 2; i++) {
+			*dst_addr++ = *src_addr;
+			*dst_addr++ = *src_addr++;
+		}
+
+		dst_size = src_size * 2;
+	}
+
+	vb2_set_plane_payload(&dst_buf->vb2_buf, 0, dst_size);
+
+	src_buf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
+	dst_buf = v4l2_m2m_dst_buf_remove(ctx->fh.m2m_ctx);
+
+	v4l2_m2m_buf_done(src_buf, VB2_BUF_STATE_DONE);
+	v4l2_m2m_buf_done(dst_buf, VB2_BUF_STATE_DONE);
+	v4l2_m2m_job_finish(audm2m_dev->m2m_dev, ctx->fh.m2m_ctx);
+}
+
+static int audm2m_querycap(struct file *file, void *priv,
+			   struct v4l2_capability *cap)
+{
+	strscpy(cap->driver, MEM2MEM_NAME, sizeof(cap->driver));
+	strscpy(cap->card, MEM2MEM_NAME, sizeof(cap->card));
+	snprintf(cap->bus_info, sizeof(cap->bus_info),
+		 "platform:%s", MEM2MEM_NAME);
+
+	return 0;
+}
+
+static int enum_fmt(struct v4l2_fmtdesc *f)
+{
+	int i, num;
+
+	num = 0;
+
+	for (i = 0; i < NUM_FORMATS; ++i) {
+		if (num == f->index)
+			break;
+		/*
+		 * Correct type but haven't reached our index yet,
+		 * just increment per-type index
+		 */
+		++num;
+	}
+
+	if (i < NUM_FORMATS) {
+		/* Format found */
+		f->pixelformat = formats[i];
+		return 0;
+	}
+
+	/* Format not found */
+	return -EINVAL;
+}
+
+static int audm2m_enum_fmt_audio_cap(struct file *file, void *priv,
+				     struct v4l2_fmtdesc *f)
+{
+	return enum_fmt(f);
+}
+
+static int audm2m_enum_fmt_audio_out(struct file *file, void *priv,
+				     struct v4l2_fmtdesc *f)
+{
+	return enum_fmt(f);
+}
+
+static int audm2m_g_fmt(struct audm2m_ctx *ctx, struct v4l2_format *f)
+{
+	struct vb2_queue *vq;
+	struct audm2m_q_data *q_data;
+
+	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
+	if (!vq)
+		return -EINVAL;
+
+	q_data = get_q_data(ctx, f->type);
+	if (!q_data)
+		return -EINVAL;
+
+	f->fmt.audio.audioformat = q_data->fourcc;
+	f->fmt.audio.channels	= q_data->channels;
+	f->fmt.audio.buffersize = q_data->buffersize;
+
+	return 0;
+}
+
+static int audm2m_g_fmt_audio_out(struct file *file, void *priv,
+				  struct v4l2_format *f)
+{
+	return audm2m_g_fmt(file2ctx(file), f);
+}
+
+static int audm2m_g_fmt_audio_cap(struct file *file, void *priv,
+				  struct v4l2_format *f)
+{
+	return audm2m_g_fmt(file2ctx(file), f);
+}
+
+static int audm2m_try_fmt(struct v4l2_format *f, snd_pcm_format_t fmt)
+{
+	f->fmt.audio.channels = 1;
+	f->fmt.audio.buffersize = f->fmt.audio.channels *
+				  snd_pcm_format_physical_width(fmt) *
+				  SAMPLE_NUM;
+	return 0;
+}
+
+static int audm2m_try_fmt_audio_cap(struct file *file, void *priv,
+				    struct v4l2_format *f)
+{
+	snd_pcm_format_t fmt;
+
+	fmt = find_format(f->fmt.audio.audioformat);
+	if (!fmt) {
+		f->fmt.audio.audioformat = formats[0];
+		fmt = find_format(f->fmt.audio.audioformat);
+	}
+
+	return audm2m_try_fmt(f, fmt);
+}
+
+static int audm2m_try_fmt_audio_out(struct file *file, void *priv,
+				    struct v4l2_format *f)
+{
+	snd_pcm_format_t fmt;
+
+	fmt = find_format(f->fmt.audio.audioformat);
+	if (!fmt) {
+		f->fmt.audio.audioformat = formats[0];
+		fmt = find_format(f->fmt.audio.audioformat);
+	}
+
+	return audm2m_try_fmt(f, fmt);
+}
+
+static int audm2m_s_fmt(struct audm2m_ctx *ctx, struct v4l2_format *f)
+{
+	struct audm2m_q_data *q_data;
+	struct vb2_queue *vq;
+	snd_pcm_format_t fmt;
+
+	vq = v4l2_m2m_get_vq(ctx->fh.m2m_ctx, f->type);
+	if (!vq)
+		return -EINVAL;
+
+	q_data = get_q_data(ctx, f->type);
+	if (!q_data)
+		return -EINVAL;
+
+	if (vb2_is_busy(vq)) {
+		v4l2_err(&ctx->dev->v4l2_dev, "%s queue busy\n", __func__);
+		return -EBUSY;
+	}
+
+	q_data->fourcc	= f->fmt.audio.audioformat;
+	q_data->channels = f->fmt.audio.channels;
+
+	fmt = find_format(f->fmt.audio.audioformat);
+	q_data->buffersize = q_data->channels *
+			     snd_pcm_format_physical_width(fmt) *
+			     SAMPLE_NUM;
+
+	dprintk(ctx->dev, 1,
+		"Format for type %s: %d/%d, fmt: %c%c%c%c\n",
+		type_name(f->type), q_data->rate,
+		q_data->channels,
+		(q_data->fourcc & 0xff),
+		(q_data->fourcc >>  8) & 0xff,
+		(q_data->fourcc >> 16) & 0xff,
+		(q_data->fourcc >> 24) & 0xff);
+
+	return 0;
+}
+
+static int audm2m_s_fmt_audio_cap(struct file *file, void *priv,
+				  struct v4l2_format *f)
+{
+	int ret;
+
+	ret = audm2m_try_fmt_audio_cap(file, priv, f);
+	if (ret)
+		return ret;
+
+	return audm2m_s_fmt(file2ctx(file), f);
+}
+
+static int audm2m_s_fmt_audio_out(struct file *file, void *priv,
+				  struct v4l2_format *f)
+{
+	int ret;
+
+	ret = audm2m_try_fmt_audio_out(file, priv, f);
+	if (ret)
+		return ret;
+
+	return audm2m_s_fmt(file2ctx(file), f);
+}
+
+static const struct v4l2_ioctl_ops audm2m_ioctl_ops = {
+	.vidioc_querycap		= audm2m_querycap,
+
+	.vidioc_enum_fmt_audio_cap	= audm2m_enum_fmt_audio_cap,
+	.vidioc_g_fmt_audio_cap		= audm2m_g_fmt_audio_cap,
+	.vidioc_try_fmt_audio_cap	= audm2m_try_fmt_audio_cap,
+	.vidioc_s_fmt_audio_cap		= audm2m_s_fmt_audio_cap,
+
+	.vidioc_enum_fmt_audio_out	= audm2m_enum_fmt_audio_out,
+	.vidioc_g_fmt_audio_out		= audm2m_g_fmt_audio_out,
+	.vidioc_try_fmt_audio_out	= audm2m_try_fmt_audio_out,
+	.vidioc_s_fmt_audio_out		= audm2m_s_fmt_audio_out,
+
+	.vidioc_reqbufs			= v4l2_m2m_ioctl_reqbufs,
+	.vidioc_querybuf		= v4l2_m2m_ioctl_querybuf,
+	.vidioc_qbuf			= v4l2_m2m_ioctl_qbuf,
+	.vidioc_dqbuf			= v4l2_m2m_ioctl_dqbuf,
+	.vidioc_prepare_buf		= v4l2_m2m_ioctl_prepare_buf,
+	.vidioc_create_bufs		= v4l2_m2m_ioctl_create_bufs,
+	.vidioc_expbuf			= v4l2_m2m_ioctl_expbuf,
+
+	.vidioc_streamon		= v4l2_m2m_ioctl_streamon,
+	.vidioc_streamoff		= v4l2_m2m_ioctl_streamoff,
+
+	.vidioc_subscribe_event		= v4l2_ctrl_subscribe_event,
+	.vidioc_unsubscribe_event	= v4l2_event_unsubscribe,
+};
+
+/*
+ * Queue operations
+ */
+static int audm2m_queue_setup(struct vb2_queue *vq,
+			      unsigned int *nbuffers,
+			      unsigned int *nplanes,
+			      unsigned int sizes[],
+			      struct device *alloc_devs[])
+{
+	struct audm2m_ctx *ctx = vb2_get_drv_priv(vq);
+	struct audm2m_q_data *q_data;
+
+	q_data = get_q_data(ctx, vq->type);
+
+	if (*nplanes)
+		return sizes[0] < q_data->buffersize ? -EINVAL : 0;
+
+	*nplanes = 1;
+	sizes[0] = q_data->buffersize;
+
+	dprintk(ctx->dev, 1, "%s: get %d buffer(s) of size %d each.\n",
+		type_name(vq->type), *nplanes, sizes[0]);
+
+	return 0;
+}
+
+static void audm2m_buf_queue(struct vb2_buffer *vb)
+{
+	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+	struct audm2m_ctx *ctx = vb2_get_drv_priv(vb->vb2_queue);
+
+	v4l2_m2m_buf_queue(ctx->fh.m2m_ctx, vbuf);
+}
+
+static int audm2m_start_streaming(struct vb2_queue *q, unsigned int count)
+{
+	struct audm2m_ctx *ctx = vb2_get_drv_priv(q);
+	struct audm2m_q_data *q_data = get_q_data(ctx, q->type);
+
+	q_data->sequence = 0;
+	return 0;
+}
+
+static void audm2m_stop_streaming(struct vb2_queue *q)
+{
+	struct audm2m_ctx *ctx = vb2_get_drv_priv(q);
+	struct vb2_v4l2_buffer *vbuf;
+
+	for (;;) {
+		if (V4L2_TYPE_IS_OUTPUT(q->type))
+			vbuf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
+		else
+			vbuf = v4l2_m2m_dst_buf_remove(ctx->fh.m2m_ctx);
+		if (!vbuf)
+			return;
+		v4l2_m2m_buf_done(vbuf, VB2_BUF_STATE_ERROR);
+	}
+}
+
+static const struct vb2_ops audm2m_qops = {
+	.queue_setup	 = audm2m_queue_setup,
+	.buf_queue	 = audm2m_buf_queue,
+	.start_streaming = audm2m_start_streaming,
+	.stop_streaming  = audm2m_stop_streaming,
+	.wait_prepare	 = vb2_ops_wait_prepare,
+	.wait_finish	 = vb2_ops_wait_finish,
+};
+
+static int queue_init(void *priv, struct vb2_queue *src_vq,
+		      struct vb2_queue *dst_vq)
+{
+	struct audm2m_ctx *ctx = priv;
+	int ret;
+
+	src_vq->type = V4L2_BUF_TYPE_AUDIO_OUTPUT;
+	src_vq->io_modes = VB2_MMAP | VB2_DMABUF;
+	src_vq->drv_priv = ctx;
+	src_vq->buf_struct_size = sizeof(struct v4l2_m2m_buffer);
+	src_vq->ops = &audm2m_qops;
+	src_vq->mem_ops = &vb2_vmalloc_memops;
+	src_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
+	src_vq->lock = &ctx->vb_mutex;
+	src_vq->min_buffers_needed = 1;
+
+	ret = vb2_queue_init(src_vq);
+	if (ret)
+		return ret;
+
+	dst_vq->type = V4L2_BUF_TYPE_AUDIO_CAPTURE;
+	dst_vq->io_modes = VB2_MMAP | VB2_DMABUF;
+	dst_vq->drv_priv = ctx;
+	dst_vq->buf_struct_size = sizeof(struct v4l2_m2m_buffer);
+	dst_vq->ops = &audm2m_qops;
+	dst_vq->mem_ops = &vb2_vmalloc_memops;
+	dst_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
+	dst_vq->lock = &ctx->vb_mutex;
+	dst_vq->min_buffers_needed = 1;
+
+	return vb2_queue_init(dst_vq);
+}
+
+static const s64 audm2m_rates[] = {
+	8000, 16000,
+};
+
+static int audm2m_op_s_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct audm2m_ctx *ctx =
+		container_of(ctrl->handler, struct audm2m_ctx, ctrl_handler);
+	int ret = 0;
+
+	switch (ctrl->id) {
+	case V4L2_CID_M2M_AUDIO_SOURCE_RATE:
+		ctx->q_data[V4L2_M2M_SRC].rate = ctrl->qmenu_int[ctrl->val];
+		break;
+	case V4L2_CID_M2M_AUDIO_DEST_RATE:
+		ctx->q_data[V4L2_M2M_DST].rate = ctrl->qmenu_int[ctrl->val];
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static const struct v4l2_ctrl_ops audm2m_ctrl_ops = {
+	.s_ctrl = audm2m_op_s_ctrl,
+};
+
+/*
+ * File operations
+ */
+static int audm2m_open(struct file *file)
+{
+	struct audm2m_dev *dev = video_drvdata(file);
+	struct audm2m_ctx *ctx = NULL;
+	snd_pcm_format_t fmt;
+	int width;
+	int rc = 0;
+
+	if (mutex_lock_interruptible(&dev->dev_mutex))
+		return -ERESTARTSYS;
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (!ctx) {
+		rc = -ENOMEM;
+		goto open_unlock;
+	}
+
+	v4l2_fh_init(&ctx->fh, video_devdata(file));
+	file->private_data = &ctx->fh;
+	ctx->dev = dev;
+
+	ctx->q_data[V4L2_M2M_SRC].fourcc = formats[0];
+	ctx->q_data[V4L2_M2M_SRC].rate = 8000;
+	ctx->q_data[V4L2_M2M_SRC].channels = 1;
+
+	/* Fix to 4096 samples */
+	fmt = find_format(formats[0]);
+	width = snd_pcm_format_physical_width(fmt);
+	ctx->q_data[V4L2_M2M_SRC].buffersize = SAMPLE_NUM * width;
+	ctx->q_data[V4L2_M2M_DST] = ctx->q_data[V4L2_M2M_SRC];
+
+	ctx->fh.m2m_ctx = v4l2_m2m_ctx_init(dev->m2m_dev, ctx, &queue_init);
+
+	mutex_init(&ctx->vb_mutex);
+
+	if (IS_ERR(ctx->fh.m2m_ctx)) {
+		rc = PTR_ERR(ctx->fh.m2m_ctx);
+
+		v4l2_fh_exit(&ctx->fh);
+		kfree(ctx);
+		goto open_unlock;
+	}
+
+	v4l2_fh_add(&ctx->fh);
+
+	dprintk(dev, 1, "Created instance: %p, m2m_ctx: %p\n",
+		ctx, ctx->fh.m2m_ctx);
+
+	v4l2_ctrl_handler_init(&ctx->ctrl_handler, 2);
+
+	v4l2_ctrl_new_int_menu(&ctx->ctrl_handler, &audm2m_ctrl_ops,
+			       V4L2_CID_M2M_AUDIO_SOURCE_RATE,
+			       ARRAY_SIZE(audm2m_rates) - 1, 0, audm2m_rates);
+	v4l2_ctrl_new_int_menu(&ctx->ctrl_handler, &audm2m_ctrl_ops,
+			       V4L2_CID_M2M_AUDIO_DEST_RATE,
+			       ARRAY_SIZE(audm2m_rates) - 1, 0, audm2m_rates);
+
+	if (ctx->ctrl_handler.error) {
+		rc = ctx->ctrl_handler.error;
+		v4l2_ctrl_handler_free(&ctx->ctrl_handler);
+		goto err_ctrl_handler;
+	}
+
+	ctx->fh.ctrl_handler = &ctx->ctrl_handler;
+
+	mutex_unlock(&dev->dev_mutex);
+
+	return 0;
+
+err_ctrl_handler:
+	v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
+open_unlock:
+	mutex_unlock(&dev->dev_mutex);
+	return rc;
+}
+
+static int audm2m_release(struct file *file)
+{
+	struct audm2m_dev *dev = video_drvdata(file);
+	struct audm2m_ctx *ctx = file2ctx(file);
+
+	dprintk(dev, 1, "Releasing instance %p\n", ctx);
+
+	v4l2_ctrl_handler_free(&ctx->ctrl_handler);
+	v4l2_fh_del(&ctx->fh);
+	v4l2_fh_exit(&ctx->fh);
+	mutex_lock(&dev->dev_mutex);
+	v4l2_m2m_ctx_release(ctx->fh.m2m_ctx);
+	mutex_unlock(&dev->dev_mutex);
+	kfree(ctx);
+
+	return 0;
+}
+
+static void audm2m_device_release(struct video_device *vdev)
+{
+	struct audm2m_dev *dev = container_of(vdev, struct audm2m_dev, vfd);
+
+	v4l2_device_unregister(&dev->v4l2_dev);
+	v4l2_m2m_release(dev->m2m_dev);
+
+#ifdef CONFIG_MEDIA_CONTROLLER
+	media_device_cleanup(&dev->mdev);
+#endif
+	kfree(dev);
+}
+
+static const struct v4l2_file_operations audm2m_fops = {
+	.owner		= THIS_MODULE,
+	.open		= audm2m_open,
+	.release	= audm2m_release,
+	.poll		= v4l2_m2m_fop_poll,
+	.unlocked_ioctl	= video_ioctl2,
+	.mmap		= v4l2_m2m_fop_mmap,
+};
+
+static const struct video_device audm2m_videodev = {
+	.name		= MEM2MEM_NAME,
+	.vfl_dir	= VFL_DIR_M2M,
+	.fops		= &audm2m_fops,
+	.ioctl_ops	= &audm2m_ioctl_ops,
+	.minor		= -1,
+	.release	= audm2m_device_release,
+	.device_caps	= V4L2_CAP_AUDIO_M2M | V4L2_CAP_STREAMING,
+};
+
+static const struct v4l2_m2m_ops m2m_ops = {
+	.device_run	= device_run,
+};
+
+static const struct media_device_ops audm2m_media_ops = {
+	.req_validate = vb2_request_validate,
+	.req_queue = v4l2_m2m_request_queue,
+};
+
+static int audm2m_probe(struct platform_device *pdev)
+{
+	struct audm2m_dev *dev;
+	struct video_device *vfd;
+	int ret;
+
+	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+	if (!dev)
+		return -ENOMEM;
+
+	ret = v4l2_device_register(&pdev->dev, &dev->v4l2_dev);
+	if (ret)
+		goto error_free;
+
+	mutex_init(&dev->dev_mutex);
+
+	dev->vfd = audm2m_videodev;
+	vfd = &dev->vfd;
+	vfd->lock = &dev->dev_mutex;
+	vfd->v4l2_dev = &dev->v4l2_dev;
+
+	video_set_drvdata(vfd, dev);
+	platform_set_drvdata(pdev, dev);
+
+	dev->m2m_dev = v4l2_m2m_init(&m2m_ops);
+	if (IS_ERR(dev->m2m_dev)) {
+		v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem device\n");
+		ret = PTR_ERR(dev->m2m_dev);
+		dev->m2m_dev = NULL;
+		goto error_dev;
+	}
+
+#ifdef CONFIG_MEDIA_CONTROLLER
+	dev->mdev.dev = &pdev->dev;
+	strscpy(dev->mdev.model, MEM2MEM_NAME, sizeof(dev->mdev.model));
+	snprintf(dev->mdev.bus_info, sizeof(dev->mdev.bus_info),
+		 "platform:%s", MEM2MEM_NAME);
+	media_device_init(&dev->mdev);
+	dev->mdev.ops = &audm2m_media_ops;
+	dev->v4l2_dev.mdev = &dev->mdev;
+#endif
+
+	ret = video_register_device(vfd, VFL_TYPE_AUDIO, 0);
+	if (ret) {
+		v4l2_err(&dev->v4l2_dev, "Failed to register video device\n");
+		goto error_m2m;
+	}
+
+#ifdef CONFIG_MEDIA_CONTROLLER
+	ret = v4l2_m2m_register_media_controller(dev->m2m_dev, vfd,
+						 MEDIA_ENT_F_PROC_AUDIO_RESAMPLER);
+	if (ret) {
+		v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem media controller\n");
+		goto error_v4l2;
+	}
+
+	ret = media_device_register(&dev->mdev);
+	if (ret) {
+		v4l2_err(&dev->v4l2_dev, "Failed to register mem2mem media device\n");
+		goto error_m2m_mc;
+	}
+#endif
+
+	v4l2_info(&dev->v4l2_dev,
+		  "Device registered as /dev/v4l-audio%d\n", vfd->num);
+
+	return 0;
+
+#ifdef CONFIG_MEDIA_CONTROLLER
+error_m2m_mc:
+	v4l2_m2m_unregister_media_controller(dev->m2m_dev);
+#endif
+error_v4l2:
+	video_unregister_device(&dev->vfd);
+	/* audm2m_device_release called by video_unregister_device to release various objects */
+	return ret;
+error_m2m:
+	v4l2_m2m_release(dev->m2m_dev);
+error_dev:
+	v4l2_device_unregister(&dev->v4l2_dev);
+error_free:
+	kfree(dev);
+
+	return ret;
+}
+
+static void audm2m_remove(struct platform_device *pdev)
+{
+	struct audm2m_dev *dev = platform_get_drvdata(pdev);
+
+	v4l2_info(&dev->v4l2_dev, "Removing " MEM2MEM_NAME);
+
+#ifdef CONFIG_MEDIA_CONTROLLER
+	media_device_unregister(&dev->mdev);
+	v4l2_m2m_unregister_media_controller(dev->m2m_dev);
+#endif
+	video_unregister_device(&dev->vfd);
+}
+
+static struct platform_driver audm2m_pdrv = {
+	.probe		= audm2m_probe,
+	.remove_new	= audm2m_remove,
+	.driver		= {
+		.name	= MEM2MEM_NAME,
+	},
+};
+
+static void __exit audm2m_exit(void)
+{
+	platform_driver_unregister(&audm2m_pdrv);
+	platform_device_unregister(&audm2m_pdev);
+}
+
+static int __init audm2m_init(void)
+{
+	int ret;
+
+	ret = platform_device_register(&audm2m_pdev);
+	if (ret)
+		return ret;
+
+	ret = platform_driver_register(&audm2m_pdrv);
+	if (ret)
+		platform_device_unregister(&audm2m_pdev);
+
+	return ret;
+}
+
+module_init(audm2m_init);
+module_exit(audm2m_exit);