@@ -240,7 +240,7 @@ static struct usb_interface_descriptor std_as_out_if1_desc = {
.bDescriptorType = USB_DT_INTERFACE,
.bAlternateSetting = 1,
- .bNumEndpoints = 1,
+ .bNumEndpoints = 2,
.bInterfaceClass = USB_CLASS_AUDIO,
.bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
.bInterfaceProtocol = UAC_VERSION_2,
@@ -317,6 +317,37 @@ static struct uac2_iso_endpoint_descriptor as_iso_out_desc = {
.wLockDelay = 0,
};
+/* STD AS ISO IN Feedback Endpoint */
+static struct usb_endpoint_descriptor fs_epin_fback_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+
+ .bEndpointAddress = USB_DIR_IN,
+ .bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_USAGE_FEEDBACK,
+ .wMaxPacketSize = cpu_to_le16(3),
+ .bInterval = 1,
+};
+
+static struct usb_endpoint_descriptor hs_epin_fback_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+
+ .bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_USAGE_FEEDBACK,
+ .wMaxPacketSize = cpu_to_le16(4),
+ .bInterval = 4,
+};
+
+static struct usb_endpoint_descriptor ss_epin_fback_desc = {
+ .bLength = USB_DT_ENDPOINT_SIZE,
+ .bDescriptorType = USB_DT_ENDPOINT,
+
+ .bEndpointAddress = USB_DIR_IN,
+ .bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_USAGE_FEEDBACK,
+ .wMaxPacketSize = cpu_to_le16(4),
+ .bInterval = 4,
+};
+
+
/* Audio Streaming IN Interface - Alt0 */
static struct usb_interface_descriptor std_as_in_if0_desc = {
.bLength = sizeof std_as_in_if0_desc,
@@ -431,6 +462,7 @@ static struct usb_descriptor_header *fs_audio_desc[] = {
(struct usb_descriptor_header *)&as_out_fmt1_desc,
(struct usb_descriptor_header *)&fs_epout_desc,
(struct usb_descriptor_header *)&as_iso_out_desc,
+ (struct usb_descriptor_header *)&fs_epin_fback_desc,
(struct usb_descriptor_header *)&std_as_in_if0_desc,
(struct usb_descriptor_header *)&std_as_in_if1_desc,
@@ -461,6 +493,7 @@ static struct usb_descriptor_header *hs_audio_desc[] = {
(struct usb_descriptor_header *)&as_out_fmt1_desc,
(struct usb_descriptor_header *)&hs_epout_desc,
(struct usb_descriptor_header *)&as_iso_out_desc,
+ (struct usb_descriptor_header *)&hs_epin_fback_desc,
(struct usb_descriptor_header *)&std_as_in_if0_desc,
(struct usb_descriptor_header *)&std_as_in_if1_desc,
@@ -492,6 +525,7 @@ static struct usb_descriptor_header *ss_audio_desc[] = {
(struct usb_descriptor_header *)&ss_epout_desc,
(struct usb_descriptor_header *)&ss_epout_desc_comp,
(struct usb_descriptor_header *)&as_iso_out_desc,
+ (struct usb_descriptor_header *)&ss_epin_fback_desc,
(struct usb_descriptor_header *)&std_as_in_if0_desc,
(struct usb_descriptor_header *)&std_as_in_if1_desc,
@@ -568,22 +602,26 @@ static void setup_headers(struct f_uac2_opts *opts,
struct usb_ss_ep_comp_descriptor *epin_desc_comp = NULL;
struct usb_endpoint_descriptor *epout_desc;
struct usb_endpoint_descriptor *epin_desc;
+ struct usb_endpoint_descriptor *epin_fback_desc;
int i;
switch (speed) {
case USB_SPEED_FULL:
epout_desc = &fs_epout_desc;
epin_desc = &fs_epin_desc;
+ epin_fback_desc = &fs_epin_fback_desc;
break;
case USB_SPEED_HIGH:
epout_desc = &hs_epout_desc;
epin_desc = &hs_epin_desc;
+ epin_fback_desc = &hs_epin_fback_desc;
break;
default:
epout_desc = &ss_epout_desc;
epin_desc = &ss_epin_desc;
epout_desc_comp = &ss_epout_desc_comp;
epin_desc_comp = &ss_epin_desc_comp;
+ epin_fback_desc = &ss_epin_fback_desc;
}
i = 0;
@@ -611,6 +649,7 @@ static void setup_headers(struct f_uac2_opts *opts,
headers[i++] = USBDHDR(epout_desc_comp);
headers[i++] = USBDHDR(&as_iso_out_desc);
+ headers[i++] = USBDHDR(epin_fback_desc);
}
if (EPIN_EN(opts)) {
headers[i++] = USBDHDR(&std_as_in_if0_desc);
@@ -844,6 +883,12 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
return -ENODEV;
}
+ agdev->in_ep_fback = usb_ep_autoconfig(gadget,
+ &fs_epin_fback_desc);
+ if (!agdev->in_ep_fback) {
+ dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
+ return -ENODEV;
+ }
}
if (EPIN_EN(uac2_opts)) {
@@ -867,8 +912,10 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
le16_to_cpu(ss_epout_desc.wMaxPacketSize));
hs_epout_desc.bEndpointAddress = fs_epout_desc.bEndpointAddress;
+ hs_epin_fback_desc.bEndpointAddress = fs_epin_fback_desc.bEndpointAddress;
hs_epin_desc.bEndpointAddress = fs_epin_desc.bEndpointAddress;
ss_epout_desc.bEndpointAddress = fs_epout_desc.bEndpointAddress;
+ ss_epin_fback_desc.bEndpointAddress = fs_epin_fback_desc.bEndpointAddress;
ss_epin_desc.bEndpointAddress = fs_epin_desc.bEndpointAddress;
setup_descriptor(uac2_opts);
@@ -38,6 +38,10 @@ struct uac_rtd_params {
unsigned int max_psize; /* MaxPacketSize of endpoint */
struct usb_request **reqs;
+
+ struct usb_request *req_fback; /* Feedback endpoint request */
+ unsigned int ffback; /* Real frequency reported by feedback endpoint */
+ bool fb_ep_enabled; /* if the ep is enabled */
};
struct snd_uac_chip {
@@ -70,6 +74,32 @@ static const struct snd_pcm_hardware uac_pcm_hardware = {
.periods_min = MIN_PERIODS,
};
+static void u_audio_set_fback_frequency(enum usb_device_speed speed,
+ unsigned int freq, void *buf)
+{
+ u32 ff = 0;
+
+ if (speed == USB_SPEED_FULL) {
+ /*
+ * Full-speed feedback endpoints report frequency
+ * in samples/microframe
+ * Format is encoded in Q10.10 left-justified in the 24 bits,
+ * so that it has a Q10.14 format.
+ */
+ ff = DIV_ROUND_UP((freq << 14), 1000);
+ } else {
+ /*
+ * High-speed feedback endpoints report frequency
+ * in samples/microframe.
+ * Format is encoded in Q12.13 fitted into four bytes so that
+ * the binary point is located between the second and the third
+ * byte fromat (that is Q16.16)
+ */
+ ff = DIV_ROUND_UP((freq << 13), 1000);
+ }
+ *(__le32 *)buf = cpu_to_le32(ff);
+}
+
static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req)
{
unsigned int pending;
@@ -173,6 +203,34 @@ static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req)
dev_err(uac->card->dev, "%d Error!\n", __LINE__);
}
+static void u_audio_iso_fback_complete(struct usb_ep *ep,
+ struct usb_request *req)
+{
+ struct uac_rtd_params *prm = req->context;
+ struct snd_uac_chip *uac = prm->uac;
+ struct g_audio *audio_dev = uac->audio_dev;
+ int status = req->status;
+ unsigned long flags;
+
+ /* i/f shutting down */
+ if (!prm->fb_ep_enabled || req->status == -ESHUTDOWN)
+ return;
+
+ /*
+ * We can't really do much about bad xfers.
+ * Afterall, the ISOCH xfers could fail legitimately.
+ */
+ if (status)
+ pr_debug("%s: iso_complete status(%d) %d/%d\n",
+ __func__, status, req->actual, req->length);
+
+ u_audio_set_fback_frequency(audio_dev->gadget->speed,
+ prm->ffback, req->buf);
+
+ if (usb_ep_queue(ep, req, GFP_ATOMIC))
+ dev_err(uac->card->dev, "%d Error!\n", __LINE__);
+}
+
static int uac_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
{
struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
@@ -335,14 +393,33 @@ static inline void free_ep(struct uac_rtd_params *prm, struct usb_ep *ep)
dev_err(uac->card->dev, "%s:%d Error!\n", __func__, __LINE__);
}
+static inline void free_ep_fback(struct uac_rtd_params *prm, struct usb_ep *ep)
+{
+ struct snd_uac_chip *uac = prm->uac;
+
+ if (!prm->fb_ep_enabled)
+ return;
+
+ prm->fb_ep_enabled = false;
+
+ if (prm->req_fback) {
+ usb_ep_dequeue(ep, prm->req_fback);
+ kfree(prm->req_fback->buf);
+ usb_ep_free_request(ep, prm->req_fback);
+ prm->req_fback = NULL;
+ }
+
+ if (usb_ep_disable(ep))
+ dev_err(uac->card->dev, "%s:%d Error!\n", __func__, __LINE__);
+}
int u_audio_start_capture(struct g_audio *audio_dev)
{
struct snd_uac_chip *uac = audio_dev->uac;
struct usb_gadget *gadget = audio_dev->gadget;
struct device *dev = &gadget->dev;
- struct usb_request *req;
- struct usb_ep *ep;
+ struct usb_request *req, *req_fback;
+ struct usb_ep *ep, *ep_fback;
struct uac_rtd_params *prm;
struct uac_params *params = &audio_dev->params;
int req_len, i;
@@ -374,6 +451,42 @@ int u_audio_start_capture(struct g_audio *audio_dev)
dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
}
+ ep_fback = audio_dev->in_ep_fback;
+ if (!ep_fback)
+ return 0;
+
+ /* Setup feedback endpoint */
+ config_ep_by_speed(gadget, &audio_dev->func, ep_fback);
+ prm->fb_ep_enabled = true;
+ usb_ep_enable(ep_fback);
+ req_len = ep_fback->maxpacket;
+
+ req_fback = usb_ep_alloc_request(ep_fback, GFP_ATOMIC);
+ if (req_fback == NULL)
+ return -ENOMEM;
+
+ prm->req_fback = req_fback;
+ req_fback->zero = 0;
+ req_fback->context = prm;
+ req_fback->length = req_len;
+ req_fback->complete = u_audio_iso_fback_complete;
+
+ req_fback->buf = kzalloc(req_len, GFP_ATOMIC);
+ if (!req_fback->buf)
+ return -ENOMEM;
+
+ /*
+ * Configure the feedback endpoint's reported frequency.
+ * Always start with original frequency since its deviation can't
+ * be meauserd at start of playback
+ */
+ prm->ffback = params->c_srate;
+ u_audio_set_fback_frequency(audio_dev->gadget->speed,
+ prm->ffback, req_fback->buf);
+
+ if (usb_ep_queue(ep_fback, req_fback, GFP_ATOMIC))
+ dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
+
return 0;
}
EXPORT_SYMBOL_GPL(u_audio_start_capture);
@@ -382,6 +495,8 @@ void u_audio_stop_capture(struct g_audio *audio_dev)
{
struct snd_uac_chip *uac = audio_dev->uac;
+ if (audio_dev->in_ep_fback)
+ free_ep_fback(&uac->c_prm, audio_dev->in_ep_fback);
free_ep(&uac->c_prm, audio_dev->out_ep);
}
EXPORT_SYMBOL_GPL(u_audio_stop_capture);
@@ -30,7 +30,10 @@ struct g_audio {
struct usb_gadget *gadget;
struct usb_ep *in_ep;
+
struct usb_ep *out_ep;
+ /* feedback IN endpoint corresponding to out_ep */
+ struct usb_ep *in_ep_fback;
/* Max packet size for all in_ep possible speeds */
unsigned int in_ep_maxpsize;