| Message ID | 20220928214806.13572-4-macroalpha82@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | Add Hynitron cstxxx Touchscreen | expand |
Hi Chris, On Wed, Sep 28, 2022 at 04:48:06PM -0500, Chris Morgan wrote: > From: Chris Morgan <macromorgan@hotmail.com> > > Add support for the Hynitron cst3xx controller found on devices such > as the Anbernic RG353P and RG353V (the Hynitron CST348). This driver > was built from sources provided by Hynitron to Anbernic (possibly > via Rockchip as an intermediary) and marked as GPLv2 in the code. > This driver was written strictly for the cst3xx series, but in > most places was left somewhat generic so support could be easily > added to other devices in the future. Thank you for the patches. This looks generally good, just a few suggestions below. > > Signed-off-by: Chris Morgan <macromorgan@hotmail.com> > --- > drivers/input/touchscreen/Kconfig | 12 + > drivers/input/touchscreen/Makefile | 1 + > drivers/input/touchscreen/hynitron_cstxxx.c | 483 ++++++++++++++++++++ > 3 files changed, 496 insertions(+) > create mode 100644 drivers/input/touchscreen/hynitron_cstxxx.c > > diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig > index 2d70c945b20a..9a9528e59c36 100644 > --- a/drivers/input/touchscreen/Kconfig > +++ b/drivers/input/touchscreen/Kconfig > @@ -422,6 +422,18 @@ config TOUCHSCREEN_HYCON_HY46XX > To compile this driver as a module, choose M here: the > module will be called hycon-hy46xx. > > +config TOUCHSCREEN_HYNITRON_CSTXXX > + tristate "Hynitron touchscreen support" > + depends on I2C > + help > + Say Y here if you have a touchscreen using a Hynitron > + touchscreen controller. > + > + If unsure, say N. > + > + To compile this driver as a module, choose M here: the > + module will be called hynitron-cstxxx. > + > config TOUCHSCREEN_ILI210X > tristate "Ilitek ILI210X based touchscreen" > depends on I2C > diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile > index 557f84fd2075..43860ca19b98 100644 > --- a/drivers/input/touchscreen/Makefile > +++ b/drivers/input/touchscreen/Makefile > @@ -47,6 +47,7 @@ obj-$(CONFIG_TOUCHSCREEN_EXC3000) += exc3000.o > obj-$(CONFIG_TOUCHSCREEN_FUJITSU) += fujitsu_ts.o > obj-$(CONFIG_TOUCHSCREEN_GOODIX) += goodix_ts.o > obj-$(CONFIG_TOUCHSCREEN_HIDEEP) += hideep.o > +obj-$(CONFIG_TOUCHSCREEN_HYNITRON_CSTXXX) += hynitron_cstxxx.o > obj-$(CONFIG_TOUCHSCREEN_ILI210X) += ili210x.o > obj-$(CONFIG_TOUCHSCREEN_ILITEK) += ilitek_ts_i2c.o > obj-$(CONFIG_TOUCHSCREEN_IMAGIS) += imagis.o > diff --git a/drivers/input/touchscreen/hynitron_cstxxx.c b/drivers/input/touchscreen/hynitron_cstxxx.c > new file mode 100644 > index 000000000000..e963968593c3 > --- /dev/null > +++ b/drivers/input/touchscreen/hynitron_cstxxx.c > @@ -0,0 +1,483 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Driver for Hynitron cstxxx Touchscreen > + * > + * Copyright (c) 2022 Chris Morgan <macromorgan@hotmail.com> > + * > + * This code is based on hynitron_core.c authored by Hynitron. > + * Note that no datasheet was available, so much of these registers > + * are undocumented. This is essentially a cleaned-up version of the > + * vendor driver with support removed for hardware I cannot test and > + * device-specific functions replated with generic functions wherever > + * possible. > + */ > + > +#include <linux/delay.h> > +#include <linux/gpio.h> > +#include <linux/i2c.h> > +#include <linux/input.h> > +#include <linux/input/mt.h> > +#include <linux/input/touchscreen.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/of_device.h> > + > +/* Per device data */ > +struct hynitron_ts_platform_data { This better be called hynitron_ts_chip as we call "platform data" something that differs per-board, not per-chip version. > + unsigned int max_touch_num; > + u32 ic_chkcode; > + int (*firmware_info)(struct i2c_client *client); > + int (*bootloader_enter)(struct i2c_client *client); > + int (*init_input)(struct i2c_client *client); > + void (*report_touch)(struct i2c_client *client); > +}; > + > +/* Data generic to all (supported and non-supported) controllers. */ > +struct hynitron_ts_data { > + const struct hynitron_ts_platform_data *pdata; > + struct i2c_client *client; > + struct device *dev; Not sure if this really needed as I think everywhere you use it you also have "client->dev" available. > + struct input_dev *input_dev; > + struct touchscreen_properties prop; > + struct gpio_desc *reset_gpio; > + struct gpio_desc *irq_gpio; I do not believe this field is being used. > + u32 fw_version; > +}; > + > +/* > + * Hard coded reset delay value of 20ms not IC dependent in > + * vendor driver. > + */ > +void hyn_reset_proc(struct i2c_client *client, int delay) > +{ > + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); > + > + gpiod_set_value(ts_data->reset_gpio, 1); > + mdelay(20); > + gpiod_set_value(ts_data->reset_gpio, 0); I think you can use gpiod_set_value_cansleep() in both places. > + if (delay) > + mdelay(delay); > +} > + > +static irqreturn_t hyn_interrupt_handler(int irq, void *dev_id) > +{ > + struct i2c_client *client = dev_id; > + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); > + > + ts_data->pdata->report_touch(client); > + > + return IRQ_HANDLED; > +} > + > +/* > + * The vendor driver would retry twice before failing to read or write > + * to the i2c device. > + */ > +int cst3xx_i2c_read(struct i2c_client *client, > + unsigned char *buf, int len) > +{ > + int ret; > + int retries = 0; > + > + while (retries < 2) { > + ret = i2c_master_recv(client, buf, len); > + if (ret <= 0) > + retries++; > + else > + break; > + } > + > + return ret; I like when functions return 0 or negative, not positive (when possible). So I wonder if we should do something like: if (ret == len) return 0; return ret < 0 ? ret : -EIO; and then in callers we can do: error = cst3xx_i2c_read(...) if (error) ... > +} > + > +int cst3xx_i2c_write(struct i2c_client *client, > + unsigned char *buf, int len) > +{ > + int ret; > + int retries = 0; > + > + while (retries < 2) { > + ret = i2c_master_send(client, buf, len); > + if (ret <= 0) > + retries++; > + else > + break; > + } > + > + return ret; > +} > + > +int cst3xx_i2c_read_register(struct i2c_client *client, > + unsigned char *buf, int len) Why don't you have register as a separate u16 argument and then use cpu_to_le16[p] to convert to on-wire format. > +{ > + int ret; > + > + ret = cst3xx_i2c_write(client, buf, 2); > + ret = cst3xx_i2c_read(client, buf, len); This clobbers errors from writing register. I also wonder if you can use i2c_transfer with 2 messages, one for writing register, and another for reading data. > + > + return ret; > +} > + > +int cst3xx_firmware_info(struct i2c_client *client) > +{ > + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); > + int ret; > + u32 tmp; > + unsigned char buf[4]; > + > + /* > + * Testing suggests command is required to allow reading of > + * firmware registers. > + */ > + buf[0] = 0xd1; > + buf[1] = 0x01; I wonder if we can define some symbolic names for these. > + ret = cst3xx_i2c_write(client, buf, 2); This looks like a candidate for error = cst3xx_i2c_send_command(client, 0x01d1); helper that would wrap cst3xx_i2c_write. > + if (ret < 0) > + return -EIO; > + > + mdelay(10); > + > + /* > + * Read register for check-code to determine if device detected > + * correctly. > + */ > + buf[0] = 0xd1; > + buf[1] = 0xfc; > + ret = cst3xx_i2c_read_register(client, buf, 4); > + if (ret < 0) > + return -EIO; > + > + memcpy(&tmp, buf, 4); > + if ((le32_to_cpu(tmp) & 0xffff0000) != ts_data->pdata->ic_chkcode) { > + dev_err(&client->dev, "%s ic mismatch\n", __func__); > + return -ENODEV; > + } > + > + mdelay(10); > + > + /* Read firmware version and test if firmware missing. */ > + buf[0] = 0xd2; > + buf[1] = 0x08; > + ret = cst3xx_i2c_read_register(client, buf, 4); > + if (ret < 0) > + return -EIO; > + > + memcpy(&tmp, buf, 4); > + > + ts_data->fw_version = le32_to_cpu(tmp); > + if (ts_data->fw_version == 0xa5a5a5a5) { > + dev_err(&client->dev, "Device firmware missing\n"); > + return -ENODEV; > + } > + > + /* > + * Testing suggests command required to exit register reading mode > + * and allow device to function as touchscreen. > + */ > + buf[0] = 0xd1; > + buf[1] = 0x09; > + ret = cst3xx_i2c_write(client, buf, 2); > + if (ret < 0) > + return -EIO; > + > + mdelay(5); > + > + return 0; > +} > + > +int cst3xx_bootloader_enter(struct i2c_client *client) > +{ > + int ret; > + u8 retry; > + unsigned char buf[4]; > + > + for (retry = 0; retry < 5; retry++) { > + hyn_reset_proc(client, (7 + retry)); > + /* set cmd to enter program mode */ > + buf[0] = 0xa0; > + buf[1] = 0x01; > + buf[2] = 0xaa; > + ret = cst3xx_i2c_write(client, buf, 3); > + if (ret < 0) > + continue; > + mdelay(2); > + > + /* check whether in program mode */ > + buf[0] = 0xa0; > + buf[1] = 0x02; > + ret = cst3xx_i2c_read_register(client, buf, 1); > + > + if (ret < 0) > + continue; > + > + if (buf[0] == 0xac) > + break; > + } > + > + if (buf[0] != 0xac) { > + dev_err(&client->dev, "%s unable to enter bootloader mode\n", > + __func__); > + return -ENODEV; > + } > + > + hyn_reset_proc(client, 40); > + > + return 0; > +} > + > +static void cst3xx_touch_update(struct hynitron_ts_data *ts_data, s32 id, > + s32 x, s32 y, s32 w) > +{ > + input_mt_slot(ts_data->input_dev, id); > + input_mt_report_slot_state(ts_data->input_dev, MT_TOOL_FINGER, 1); > + touchscreen_report_pos(ts_data->input_dev, &ts_data->prop, x, y, true); > + input_report_abs(ts_data->input_dev, ABS_MT_TOUCH_MAJOR, w); > +} > + > +int cst3xx_finish_touch_read(struct i2c_client *client) > +{ > + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); > + unsigned char buf[3]; > + int ret; > + > + buf[0] = 0xd0; > + buf[1] = 0x00; > + buf[2] = 0xab; > + ret = cst3xx_i2c_write(ts_data->client, buf, 3); > + if (ret < 0) { > + dev_err(ts_data->dev, "send read touch info ending failed.\n"); > + return ret; > + } > + > + return 0; > +} > + > +/* > + * Handle events from IRQ. Note that for cst3xx it appears that IRQ > + * fires continuously while touched, otherwise once every 1500ms > + * when not touched (assume touchscreen waking up periodically). > + */ > +static void cst3xx_touch_report(struct i2c_client *client) > +{ > + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); > + unsigned char buf[30]; > + unsigned char finger_id, sw; > + unsigned int input_x = 0; > + unsigned int input_y = 0; > + unsigned int input_w = 0; > + int idx = 0; > + int i, ret; > + int touch_cnt, i2c_len; > + > + buf[0] = 0xd0; > + buf[1] = 0x00; > + > + /* Read and validate the first bits of input data. */ > + ret = cst3xx_i2c_read_register(ts_data->client, buf, 7); > + if ((ret < 0) || (buf[6] != 0xab) || (buf[0] == 0xab)) > + goto end; > + > + touch_cnt = buf[5] & 0x7f; > + > + /* If no touches registered, clear the input slots. */ > + if (touch_cnt == 0) { > + input_mt_sync_frame(ts_data->input_dev); > + input_sync(ts_data->input_dev); > + return; > + } > + > + /* > + * If we have only one touch, we have enough data to process > + * the event. If we have more than one touch we need to read > + * the rest of the data. Note these functions are not combined > + * because this is how it was done in the vendor driver and I > + * lack the datasheet to modify the necessary values for > + * reading from all the registers at once. > + */ > + if (touch_cnt > 1) { > + buf[5] = 0xd0; > + buf[6] = 0x07; > + i2c_len = (touch_cnt - 1) * 5 + 1; > + ret = cst3xx_i2c_read_register(ts_data->client, > + &buf[5], i2c_len); > + if (ret < 0) > + goto end; > + i2c_len += 5; > + > + if (buf[i2c_len - 1] != 0xab) > + goto end; > + } > + > + ret = cst3xx_finish_touch_read(client); Do we have to do this here? Can we jump to "end" label? The function looks a bit messy. > + if (ret < 0) { > + dev_err(ts_data->dev, "cst3xx touch read failure\n"); > + return; > + } > + > + for (i = 0; i < touch_cnt; i++) { > + input_x = ((buf[idx + 1] << 4) | ((buf[idx + 3] >> 4) & 0x0f)); > + input_y = ((buf[idx + 2] << 4) | (buf[idx + 3] & 0x0f)); > + input_w = (buf[idx + 4] >> 3); > + sw = (buf[idx] & 0x0f) >> 1; > + finger_id = (buf[idx] >> 4) & 0x0f; > + > + /* Sanity check we don't have more fingers than we expect */ > + if (ts_data->pdata->max_touch_num < finger_id) { > + dev_err(ts_data->dev, "cst3xx touch read failure\n"); > + break; > + } > + > + /* sw value of 0 means no touch, 0x03 means touch */ > + if (sw == 0x03) > + cst3xx_touch_update(ts_data, finger_id, > + input_x, input_y, input_w); > + > + idx += 5; > + } > + > + input_mt_sync_frame(ts_data->input_dev); > + input_sync(ts_data->input_dev); > + return; > +end: > + cst3xx_finish_touch_read(client); > + dev_err(ts_data->dev, "cst3xx touch read failure\n"); > +} > + > +int cst3xx_input_dev_int(struct i2c_client *client) > +{ > + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); > + int ret = 0; Call this variable "error" and not initialize to 0. > + > + ts_data->input_dev = devm_input_allocate_device(&ts_data->client->dev); > + if (!ts_data->input_dev) { > + dev_err(&ts_data->client->dev, > + "Failed to allocate input device.\n"); > + return -ENOMEM; > + } > + > + ts_data->input_dev->name = "Hynitron cst3xx Touchscreen"; > + ts_data->input_dev->phys = "input/ts"; > + ts_data->input_dev->id.bustype = BUS_I2C; > + ts_data->input_dev->dev.parent = ts_data->dev; No need to set parent because devm_input_allocate_device() does this for us. > + > + input_set_drvdata(ts_data->input_dev, ts_data); > + > + input_set_capability(ts_data->input_dev, EV_ABS, ABS_MT_POSITION_X); > + input_set_capability(ts_data->input_dev, EV_ABS, ABS_MT_POSITION_Y); > + input_set_abs_params(ts_data->input_dev, ABS_MT_TOUCH_MAJOR, > + 0, 255, 0, 0); > + > + touchscreen_parse_properties(ts_data->input_dev, true, &ts_data->prop); > + > + if (!ts_data->prop.max_x || !ts_data->prop.max_y) { > + dev_err(&ts_data->client->dev, > + "Invalid x/y (%d, %d), using defaults\n", > + ts_data->prop.max_x, ts_data->prop.max_y); > + ts_data->prop.max_x = 1152; > + ts_data->prop.max_y = 1920; > + input_abs_set_max(ts_data->input_dev, > + ABS_MT_POSITION_X, ts_data->prop.max_x); > + input_abs_set_max(ts_data->input_dev, > + ABS_MT_POSITION_Y, ts_data->prop.max_y); > + } > + > + input_mt_init_slots(ts_data->input_dev, ts_data->pdata->max_touch_num, > + INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); This mat fail so please handle errors here too. > + > + ret = input_register_device(ts_data->input_dev); > + if (ret < 0) { > + dev_err(&ts_data->client->dev, > + "Input device registration failed\n"); > + return ret; > + } > + > + return ret; return 0; > +} > + > +static int hyn_probe(struct i2c_client *client) > +{ > + struct hynitron_ts_data *ts_data; > + int ret; Call this variable "error" please. > + > + ts_data = devm_kzalloc(&client->dev, sizeof(*ts_data), GFP_KERNEL); > + if (!ts_data) > + return -ENOMEM; > + > + ts_data->client = client; > + ts_data->dev = &client->dev; > + i2c_set_clientdata(client, ts_data); > + > + ts_data->reset_gpio = devm_gpiod_get(&client->dev, > + "reset", GPIOD_OUT_LOW); I've become fond of: error = PTR_ERR_OR_ZERO(ts_data->reset_gpio); > + if (IS_ERR(ts_data->reset_gpio)) { > + ret = PTR_ERR(ts_data->reset_gpio); > + dev_err(&client->dev, "request reset gpio failed: %d\n", ret); > + return ret; > + } > + > + ts_data->pdata = of_device_get_match_data(&client->dev); > + if (!ts_data->pdata) > + return -EINVAL; > + > + hyn_reset_proc(client, 60); > + > + ret = ts_data->pdata->bootloader_enter(client); > + if (ret < 0) > + return ret; > + > + ret = ts_data->pdata->init_input(client); > + if (ret < 0) > + return ret; > + > + ret = ts_data->pdata->firmware_info(client); > + if (ret < 0) > + return ret; > + > + ret = devm_request_threaded_irq(&client->dev, client->irq, NULL, > + hyn_interrupt_handler, > + IRQF_ONESHOT, > + "Hynitron Touch Int", client); > + if (ret < 0) { > + dev_err(&client->dev, "failed to request IRQ\n"); > + return ret; > + } > + > + return 0; > +} > + > +static const struct hynitron_ts_platform_data cst3xx_data = { > + .max_touch_num = 5, > + .ic_chkcode = 0xcaca0000, > + .firmware_info = &cst3xx_firmware_info, > + .bootloader_enter = &cst3xx_bootloader_enter, > + .init_input = &cst3xx_input_dev_int, > + .report_touch = &cst3xx_touch_report, > +}; > + > +static const struct i2c_device_id hyn_tpd_id[] = { > + { .name = "hynitron_ts", 0 }, > + { /* sentinel */ }, > +}; > +MODULE_DEVICE_TABLE(i2c, hyn_tpd_id); > + > +static const struct of_device_id hyn_dt_match[] = { > + { .compatible = "hynitron,cst3xx", .data = &cst3xx_data }, > + { /* sentinel */ }, > +}; > +MODULE_DEVICE_TABLE(of, hyn_dt_match); > + > +static struct i2c_driver hynitron_i2c_driver = { > + .driver = { > + .name = "Hynitron-TS", > + .of_match_table = of_match_ptr(hyn_dt_match), > + .probe_type = PROBE_PREFER_ASYNCHRONOUS, > + }, > + .id_table = hyn_tpd_id, > + .probe_new = hyn_probe, > +}; > + > +module_i2c_driver(hynitron_i2c_driver); > + > +MODULE_AUTHOR("Chris Morgan"); > +MODULE_DESCRIPTION("Hynitron Touchscreen Driver"); > +MODULE_LICENSE("GPL"); > -- > 2.25.1 > Thanks.
On Thu, Sep 29, 2022 at 09:24:27AM -0700, Dmitry Torokhov wrote: > Hi Chris, > > On Wed, Sep 28, 2022 at 04:48:06PM -0500, Chris Morgan wrote: > > From: Chris Morgan <macromorgan@hotmail.com> > > > > Add support for the Hynitron cst3xx controller found on devices such > > as the Anbernic RG353P and RG353V (the Hynitron CST348). This driver > > was built from sources provided by Hynitron to Anbernic (possibly > > via Rockchip as an intermediary) and marked as GPLv2 in the code. > > This driver was written strictly for the cst3xx series, but in > > most places was left somewhat generic so support could be easily > > added to other devices in the future. > > Thank you for the patches. This looks generally good, just a few > suggestions below. > > > > > Signed-off-by: Chris Morgan <macromorgan@hotmail.com> > > --- > > drivers/input/touchscreen/Kconfig | 12 + > > drivers/input/touchscreen/Makefile | 1 + > > drivers/input/touchscreen/hynitron_cstxxx.c | 483 ++++++++++++++++++++ > > 3 files changed, 496 insertions(+) > > create mode 100644 drivers/input/touchscreen/hynitron_cstxxx.c > > > > diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig > > index 2d70c945b20a..9a9528e59c36 100644 > > --- a/drivers/input/touchscreen/Kconfig > > +++ b/drivers/input/touchscreen/Kconfig > > @@ -422,6 +422,18 @@ config TOUCHSCREEN_HYCON_HY46XX > > To compile this driver as a module, choose M here: the > > module will be called hycon-hy46xx. > > > > +config TOUCHSCREEN_HYNITRON_CSTXXX > > + tristate "Hynitron touchscreen support" > > + depends on I2C > > + help > > + Say Y here if you have a touchscreen using a Hynitron > > + touchscreen controller. > > + > > + If unsure, say N. > > + > > + To compile this driver as a module, choose M here: the > > + module will be called hynitron-cstxxx. > > + > > config TOUCHSCREEN_ILI210X > > tristate "Ilitek ILI210X based touchscreen" > > depends on I2C > > diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile > > index 557f84fd2075..43860ca19b98 100644 > > --- a/drivers/input/touchscreen/Makefile > > +++ b/drivers/input/touchscreen/Makefile > > @@ -47,6 +47,7 @@ obj-$(CONFIG_TOUCHSCREEN_EXC3000) += exc3000.o > > obj-$(CONFIG_TOUCHSCREEN_FUJITSU) += fujitsu_ts.o > > obj-$(CONFIG_TOUCHSCREEN_GOODIX) += goodix_ts.o > > obj-$(CONFIG_TOUCHSCREEN_HIDEEP) += hideep.o > > +obj-$(CONFIG_TOUCHSCREEN_HYNITRON_CSTXXX) += hynitron_cstxxx.o > > obj-$(CONFIG_TOUCHSCREEN_ILI210X) += ili210x.o > > obj-$(CONFIG_TOUCHSCREEN_ILITEK) += ilitek_ts_i2c.o > > obj-$(CONFIG_TOUCHSCREEN_IMAGIS) += imagis.o > > diff --git a/drivers/input/touchscreen/hynitron_cstxxx.c b/drivers/input/touchscreen/hynitron_cstxxx.c > > new file mode 100644 > > index 000000000000..e963968593c3 > > --- /dev/null > > +++ b/drivers/input/touchscreen/hynitron_cstxxx.c > > @@ -0,0 +1,483 @@ > > +// SPDX-License-Identifier: GPL-2.0-only > > +/* > > + * Driver for Hynitron cstxxx Touchscreen > > + * > > + * Copyright (c) 2022 Chris Morgan <macromorgan@hotmail.com> > > + * > > + * This code is based on hynitron_core.c authored by Hynitron. > > + * Note that no datasheet was available, so much of these registers > > + * are undocumented. This is essentially a cleaned-up version of the > > + * vendor driver with support removed for hardware I cannot test and > > + * device-specific functions replated with generic functions wherever > > + * possible. > > + */ > > + > > +#include <linux/delay.h> > > +#include <linux/gpio.h> > > +#include <linux/i2c.h> > > +#include <linux/input.h> > > +#include <linux/input/mt.h> > > +#include <linux/input/touchscreen.h> > > +#include <linux/module.h> > > +#include <linux/of.h> > > +#include <linux/of_device.h> > > + > > +/* Per device data */ > > +struct hynitron_ts_platform_data { > > This better be called hynitron_ts_chip as we call "platform data" > something that differs per-board, not per-chip version. Acknowledged. > > > + unsigned int max_touch_num; > > + u32 ic_chkcode; > > + int (*firmware_info)(struct i2c_client *client); > > + int (*bootloader_enter)(struct i2c_client *client); > > + int (*init_input)(struct i2c_client *client); > > + void (*report_touch)(struct i2c_client *client); > > +}; > > + > > +/* Data generic to all (supported and non-supported) controllers. */ > > +struct hynitron_ts_data { > > + const struct hynitron_ts_platform_data *pdata; > > + struct i2c_client *client; > > + struct device *dev; > > Not sure if this really needed as I think everywhere you use it you also > have "client->dev" available. > Acknowledged. > > + struct input_dev *input_dev; > > + struct touchscreen_properties prop; > > + struct gpio_desc *reset_gpio; > > + struct gpio_desc *irq_gpio; > > I do not believe this field is being used. > Acknowledged. > > + u32 fw_version; > > +}; > > + > > +/* > > + * Hard coded reset delay value of 20ms not IC dependent in > > + * vendor driver. > > + */ > > +void hyn_reset_proc(struct i2c_client *client, int delay) > > +{ > > + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); > > + > > + gpiod_set_value(ts_data->reset_gpio, 1); > > + mdelay(20); > > + gpiod_set_value(ts_data->reset_gpio, 0); > > I think you can use gpiod_set_value_cansleep() in both places. > Acknowledged. I'll confirm it works and if so make the change. If not, I'll note it in the next version notes. > > + if (delay) > > + mdelay(delay); > > +} > > + > > +static irqreturn_t hyn_interrupt_handler(int irq, void *dev_id) > > +{ > > + struct i2c_client *client = dev_id; > > + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); > > + > > + ts_data->pdata->report_touch(client); > > + > > + return IRQ_HANDLED; > > +} > > + > > +/* > > + * The vendor driver would retry twice before failing to read or write > > + * to the i2c device. > > + */ > > +int cst3xx_i2c_read(struct i2c_client *client, > > + unsigned char *buf, int len) > > +{ > > + int ret; > > + int retries = 0; > > + > > + while (retries < 2) { > > + ret = i2c_master_recv(client, buf, len); > > + if (ret <= 0) > > + retries++; > > + else > > + break; > > + } > > + > > + return ret; > > I like when functions return 0 or negative, not positive (when > possible). So I wonder if we should do something like: > Understood, I'll redo this to make it return 0 on success instead of a positive value. > if (ret == len) > return 0; > > return ret < 0 ? ret : -EIO; > > and then in callers we can do: > > error = cst3xx_i2c_read(...) > if (error) > ... > > > +} > > + > > +int cst3xx_i2c_write(struct i2c_client *client, > > + unsigned char *buf, int len) > > +{ > > + int ret; > > + int retries = 0; > > + > > + while (retries < 2) { > > + ret = i2c_master_send(client, buf, len); > > + if (ret <= 0) > > + retries++; > > + else > > + break; > > + } > > + > > + return ret; > > +} > > + > > +int cst3xx_i2c_read_register(struct i2c_client *client, > > + unsigned char *buf, int len) > Is my ignorance of the i2c protocol an acceptable answer? I'll try this out on the next go-round. > Why don't you have register as a separate u16 argument and then use > cpu_to_le16[p] to convert to on-wire format. > > > +{ > > + int ret; > > + > > + ret = cst3xx_i2c_write(client, buf, 2); > > + ret = cst3xx_i2c_read(client, buf, len); > > This clobbers errors from writing register. I also wonder if you can > use i2c_transfer with 2 messages, one for writing register, and another > for reading data. > > > + > > + return ret; > > +} > > + > > +int cst3xx_firmware_info(struct i2c_client *client) > > +{ > > + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); > > + int ret; > > + u32 tmp; > > + unsigned char buf[4]; > > + > > + /* > > + * Testing suggests command is required to allow reading of > > + * firmware registers. > > + */ > > + buf[0] = 0xd1; > > + buf[1] = 0x01; > > I wonder if we can define some symbolic names for these. > I don't know what they mean, the best I can do is guess. No datasheet sadly. I know from preliminary testing if I don't send this initial command here the rest of them fail, so I assume this command allows me to read certain registers? > > + ret = cst3xx_i2c_write(client, buf, 2); > > This looks like a candidate for > > error = cst3xx_i2c_send_command(client, 0x01d1); > > helper that would wrap cst3xx_i2c_write. Acknowledged. > > > + if (ret < 0) > > + return -EIO; > > + > > + mdelay(10); > > + > > + /* > > + * Read register for check-code to determine if device detected > > + * correctly. > > + */ > > + buf[0] = 0xd1; > > + buf[1] = 0xfc; > > + ret = cst3xx_i2c_read_register(client, buf, 4); > > + if (ret < 0) > > + return -EIO; > > + > > + memcpy(&tmp, buf, 4); > > + if ((le32_to_cpu(tmp) & 0xffff0000) != ts_data->pdata->ic_chkcode) { > > + dev_err(&client->dev, "%s ic mismatch\n", __func__); > > + return -ENODEV; > > + } > > + > > + mdelay(10); > > + > > + /* Read firmware version and test if firmware missing. */ > > + buf[0] = 0xd2; > > + buf[1] = 0x08; > > + ret = cst3xx_i2c_read_register(client, buf, 4); > > + if (ret < 0) > > + return -EIO; > > + > > + memcpy(&tmp, buf, 4); > > + > > + ts_data->fw_version = le32_to_cpu(tmp); > > + if (ts_data->fw_version == 0xa5a5a5a5) { > > + dev_err(&client->dev, "Device firmware missing\n"); > > + return -ENODEV; > > + } > > + > > + /* > > + * Testing suggests command required to exit register reading mode > > + * and allow device to function as touchscreen. > > + */ > > + buf[0] = 0xd1; > > + buf[1] = 0x09; > > + ret = cst3xx_i2c_write(client, buf, 2); > > + if (ret < 0) > > + return -EIO; > > + > > + mdelay(5); > > + > > + return 0; > > +} > > + > > +int cst3xx_bootloader_enter(struct i2c_client *client) > > +{ > > + int ret; > > + u8 retry; > > + unsigned char buf[4]; > > + > > + for (retry = 0; retry < 5; retry++) { > > + hyn_reset_proc(client, (7 + retry)); > > + /* set cmd to enter program mode */ > > + buf[0] = 0xa0; > > + buf[1] = 0x01; > > + buf[2] = 0xaa; > > + ret = cst3xx_i2c_write(client, buf, 3); > > + if (ret < 0) > > + continue; > > + mdelay(2); > > + > > + /* check whether in program mode */ > > + buf[0] = 0xa0; > > + buf[1] = 0x02; > > + ret = cst3xx_i2c_read_register(client, buf, 1); > > + > > + if (ret < 0) > > + continue; > > + > > + if (buf[0] == 0xac) > > + break; > > + } > > + > > + if (buf[0] != 0xac) { > > + dev_err(&client->dev, "%s unable to enter bootloader mode\n", > > + __func__); > > + return -ENODEV; > > + } > > + > > + hyn_reset_proc(client, 40); > > + > > + return 0; > > +} > > + > > +static void cst3xx_touch_update(struct hynitron_ts_data *ts_data, s32 id, > > + s32 x, s32 y, s32 w) > > +{ > > + input_mt_slot(ts_data->input_dev, id); > > + input_mt_report_slot_state(ts_data->input_dev, MT_TOOL_FINGER, 1); > > + touchscreen_report_pos(ts_data->input_dev, &ts_data->prop, x, y, true); > > + input_report_abs(ts_data->input_dev, ABS_MT_TOUCH_MAJOR, w); > > +} > > + > > +int cst3xx_finish_touch_read(struct i2c_client *client) > > +{ > > + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); > > + unsigned char buf[3]; > > + int ret; > > + > > + buf[0] = 0xd0; > > + buf[1] = 0x00; > > + buf[2] = 0xab; > > + ret = cst3xx_i2c_write(ts_data->client, buf, 3); > > + if (ret < 0) { > > + dev_err(ts_data->dev, "send read touch info ending failed.\n"); > > + return ret; > > + } > > + > > + return 0; > > +} > > + > > +/* > > + * Handle events from IRQ. Note that for cst3xx it appears that IRQ > > + * fires continuously while touched, otherwise once every 1500ms > > + * when not touched (assume touchscreen waking up periodically). > > + */ > > +static void cst3xx_touch_report(struct i2c_client *client) > > +{ > > + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); > > + unsigned char buf[30]; > > + unsigned char finger_id, sw; > > + unsigned int input_x = 0; > > + unsigned int input_y = 0; > > + unsigned int input_w = 0; > > + int idx = 0; > > + int i, ret; > > + int touch_cnt, i2c_len; > > + > > + buf[0] = 0xd0; > > + buf[1] = 0x00; > > + > > + /* Read and validate the first bits of input data. */ > > + ret = cst3xx_i2c_read_register(ts_data->client, buf, 7); > > + if ((ret < 0) || (buf[6] != 0xab) || (buf[0] == 0xab)) > > + goto end; > > + > > + touch_cnt = buf[5] & 0x7f; > > + > > + /* If no touches registered, clear the input slots. */ > > + if (touch_cnt == 0) { > > + input_mt_sync_frame(ts_data->input_dev); > > + input_sync(ts_data->input_dev); > > + return; > > + } > > + > > + /* > > + * If we have only one touch, we have enough data to process > > + * the event. If we have more than one touch we need to read > > + * the rest of the data. Note these functions are not combined > > + * because this is how it was done in the vendor driver and I > > + * lack the datasheet to modify the necessary values for > > + * reading from all the registers at once. > > + */ > > + if (touch_cnt > 1) { > > + buf[5] = 0xd0; > > + buf[6] = 0x07; > > + i2c_len = (touch_cnt - 1) * 5 + 1; > > + ret = cst3xx_i2c_read_register(ts_data->client, > > + &buf[5], i2c_len); > > + if (ret < 0) > > + goto end; > > + i2c_len += 5; > > + > > + if (buf[i2c_len - 1] != 0xab) > > + goto end; > > + } > > + > > + ret = cst3xx_finish_touch_read(client); > > Do we have to do this here? Can we jump to "end" label? The function > looks a bit messy. > I'll see if I can clean it up better. > > + if (ret < 0) { > > + dev_err(ts_data->dev, "cst3xx touch read failure\n"); > > + return; > > + } > > + > > + for (i = 0; i < touch_cnt; i++) { > > + input_x = ((buf[idx + 1] << 4) | ((buf[idx + 3] >> 4) & 0x0f)); > > + input_y = ((buf[idx + 2] << 4) | (buf[idx + 3] & 0x0f)); > > + input_w = (buf[idx + 4] >> 3); > > + sw = (buf[idx] & 0x0f) >> 1; > > + finger_id = (buf[idx] >> 4) & 0x0f; > > + > > + /* Sanity check we don't have more fingers than we expect */ > > + if (ts_data->pdata->max_touch_num < finger_id) { > > + dev_err(ts_data->dev, "cst3xx touch read failure\n"); > > + break; > > + } > > + > > + /* sw value of 0 means no touch, 0x03 means touch */ > > + if (sw == 0x03) > > + cst3xx_touch_update(ts_data, finger_id, > > + input_x, input_y, input_w); > > + > > + idx += 5; > > + } > > + > > + input_mt_sync_frame(ts_data->input_dev); > > + input_sync(ts_data->input_dev); > > + return; > > +end: > > + cst3xx_finish_touch_read(client); > > + dev_err(ts_data->dev, "cst3xx touch read failure\n"); > > +} > > + > > +int cst3xx_input_dev_int(struct i2c_client *client) > > +{ > > + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); > > + int ret = 0; > > Call this variable "error" and not initialize to 0. > Acknowledged. > > + > > + ts_data->input_dev = devm_input_allocate_device(&ts_data->client->dev); > > + if (!ts_data->input_dev) { > > + dev_err(&ts_data->client->dev, > > + "Failed to allocate input device.\n"); > > + return -ENOMEM; > > + } > > + > > + ts_data->input_dev->name = "Hynitron cst3xx Touchscreen"; > > + ts_data->input_dev->phys = "input/ts"; > > + ts_data->input_dev->id.bustype = BUS_I2C; > > + ts_data->input_dev->dev.parent = ts_data->dev; > > No need to set parent because devm_input_allocate_device() does this for > us. Thanks, I'll do that. > > > + > > + input_set_drvdata(ts_data->input_dev, ts_data); > > + > > + input_set_capability(ts_data->input_dev, EV_ABS, ABS_MT_POSITION_X); > > + input_set_capability(ts_data->input_dev, EV_ABS, ABS_MT_POSITION_Y); > > + input_set_abs_params(ts_data->input_dev, ABS_MT_TOUCH_MAJOR, > > + 0, 255, 0, 0); > > + > > + touchscreen_parse_properties(ts_data->input_dev, true, &ts_data->prop); > > + > > + if (!ts_data->prop.max_x || !ts_data->prop.max_y) { > > + dev_err(&ts_data->client->dev, > > + "Invalid x/y (%d, %d), using defaults\n", > > + ts_data->prop.max_x, ts_data->prop.max_y); > > + ts_data->prop.max_x = 1152; > > + ts_data->prop.max_y = 1920; > > + input_abs_set_max(ts_data->input_dev, > > + ABS_MT_POSITION_X, ts_data->prop.max_x); > > + input_abs_set_max(ts_data->input_dev, > > + ABS_MT_POSITION_Y, ts_data->prop.max_y); > > + } > > + > > + input_mt_init_slots(ts_data->input_dev, ts_data->pdata->max_touch_num, > > + INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); > > This mat fail so please handle errors here too. > Acknowledged. > > + > > + ret = input_register_device(ts_data->input_dev); > > + if (ret < 0) { > > + dev_err(&ts_data->client->dev, > > + "Input device registration failed\n"); > > + return ret; > > + } > > + > > + return ret; > > return 0; > Acknowledged. > > +} > > + > > +static int hyn_probe(struct i2c_client *client) > > +{ > > + struct hynitron_ts_data *ts_data; > > + int ret; > > Call this variable "error" please. > Will do. > > + > > + ts_data = devm_kzalloc(&client->dev, sizeof(*ts_data), GFP_KERNEL); > > + if (!ts_data) > > + return -ENOMEM; > > + > > + ts_data->client = client; > > + ts_data->dev = &client->dev; > > + i2c_set_clientdata(client, ts_data); > > + > > + ts_data->reset_gpio = devm_gpiod_get(&client->dev, > > + "reset", GPIOD_OUT_LOW); > > I've become fond of: > > error = PTR_ERR_OR_ZERO(ts_data->reset_gpio); > Okay, I'll do that. > > + if (IS_ERR(ts_data->reset_gpio)) { > > + ret = PTR_ERR(ts_data->reset_gpio); > > + dev_err(&client->dev, "request reset gpio failed: %d\n", ret); > > + return ret; > > + } > > + > > + ts_data->pdata = of_device_get_match_data(&client->dev); > > + if (!ts_data->pdata) > > + return -EINVAL; > > + > > + hyn_reset_proc(client, 60); > > + > > + ret = ts_data->pdata->bootloader_enter(client); > > + if (ret < 0) > > + return ret; > > + > > + ret = ts_data->pdata->init_input(client); > > + if (ret < 0) > > + return ret; > > + > > + ret = ts_data->pdata->firmware_info(client); > > + if (ret < 0) > > + return ret; > > + > > + ret = devm_request_threaded_irq(&client->dev, client->irq, NULL, > > + hyn_interrupt_handler, > > + IRQF_ONESHOT, > > + "Hynitron Touch Int", client); > > + if (ret < 0) { > > + dev_err(&client->dev, "failed to request IRQ\n"); > > + return ret; > > + } > > + > > + return 0; > > +} > > + > > +static const struct hynitron_ts_platform_data cst3xx_data = { > > + .max_touch_num = 5, > > + .ic_chkcode = 0xcaca0000, > > + .firmware_info = &cst3xx_firmware_info, > > + .bootloader_enter = &cst3xx_bootloader_enter, > > + .init_input = &cst3xx_input_dev_int, > > + .report_touch = &cst3xx_touch_report, > > +}; > > + > > +static const struct i2c_device_id hyn_tpd_id[] = { > > + { .name = "hynitron_ts", 0 }, > > + { /* sentinel */ }, > > +}; > > +MODULE_DEVICE_TABLE(i2c, hyn_tpd_id); > > + > > +static const struct of_device_id hyn_dt_match[] = { > > + { .compatible = "hynitron,cst3xx", .data = &cst3xx_data }, > > + { /* sentinel */ }, > > +}; > > +MODULE_DEVICE_TABLE(of, hyn_dt_match); > > + > > +static struct i2c_driver hynitron_i2c_driver = { > > + .driver = { > > + .name = "Hynitron-TS", > > + .of_match_table = of_match_ptr(hyn_dt_match), > > + .probe_type = PROBE_PREFER_ASYNCHRONOUS, > > + }, > > + .id_table = hyn_tpd_id, > > + .probe_new = hyn_probe, > > +}; > > + > > +module_i2c_driver(hynitron_i2c_driver); > > + > > +MODULE_AUTHOR("Chris Morgan"); > > +MODULE_DESCRIPTION("Hynitron Touchscreen Driver"); > > +MODULE_LICENSE("GPL"); > > -- > > 2.25.1 > > > > Thanks. Thank you for your input. I'll make the requested changes and resubmit. > > -- > Dmitry
On Fri, Sep 30, 2022 at 10:34:50AM -0500, Chris Morgan wrote: > On Thu, Sep 29, 2022 at 09:24:27AM -0700, Dmitry Torokhov wrote: > > Hi Chris, > > > > On Wed, Sep 28, 2022 at 04:48:06PM -0500, Chris Morgan wrote: > > > + > > > + /* > > > + * Testing suggests command is required to allow reading of > > > + * firmware registers. > > > + */ > > > + buf[0] = 0xd1; > > > + buf[1] = 0x01; > > > > I wonder if we can define some symbolic names for these. > > > > I don't know what they mean, the best I can do is guess. No > datasheet sadly. I know from preliminary testing if I don't > send this initial command here the rest of them fail, so I > assume this command allows me to read certain registers? Guessing is fine, we can adjust them if we ever get a hold of the data sheet. Thanks.
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig index 2d70c945b20a..9a9528e59c36 100644 --- a/drivers/input/touchscreen/Kconfig +++ b/drivers/input/touchscreen/Kconfig @@ -422,6 +422,18 @@ config TOUCHSCREEN_HYCON_HY46XX To compile this driver as a module, choose M here: the module will be called hycon-hy46xx. +config TOUCHSCREEN_HYNITRON_CSTXXX + tristate "Hynitron touchscreen support" + depends on I2C + help + Say Y here if you have a touchscreen using a Hynitron + touchscreen controller. + + If unsure, say N. + + To compile this driver as a module, choose M here: the + module will be called hynitron-cstxxx. + config TOUCHSCREEN_ILI210X tristate "Ilitek ILI210X based touchscreen" depends on I2C diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile index 557f84fd2075..43860ca19b98 100644 --- a/drivers/input/touchscreen/Makefile +++ b/drivers/input/touchscreen/Makefile @@ -47,6 +47,7 @@ obj-$(CONFIG_TOUCHSCREEN_EXC3000) += exc3000.o obj-$(CONFIG_TOUCHSCREEN_FUJITSU) += fujitsu_ts.o obj-$(CONFIG_TOUCHSCREEN_GOODIX) += goodix_ts.o obj-$(CONFIG_TOUCHSCREEN_HIDEEP) += hideep.o +obj-$(CONFIG_TOUCHSCREEN_HYNITRON_CSTXXX) += hynitron_cstxxx.o obj-$(CONFIG_TOUCHSCREEN_ILI210X) += ili210x.o obj-$(CONFIG_TOUCHSCREEN_ILITEK) += ilitek_ts_i2c.o obj-$(CONFIG_TOUCHSCREEN_IMAGIS) += imagis.o diff --git a/drivers/input/touchscreen/hynitron_cstxxx.c b/drivers/input/touchscreen/hynitron_cstxxx.c new file mode 100644 index 000000000000..e963968593c3 --- /dev/null +++ b/drivers/input/touchscreen/hynitron_cstxxx.c @@ -0,0 +1,483 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Driver for Hynitron cstxxx Touchscreen + * + * Copyright (c) 2022 Chris Morgan <macromorgan@hotmail.com> + * + * This code is based on hynitron_core.c authored by Hynitron. + * Note that no datasheet was available, so much of these registers + * are undocumented. This is essentially a cleaned-up version of the + * vendor driver with support removed for hardware I cannot test and + * device-specific functions replated with generic functions wherever + * possible. + */ + +#include <linux/delay.h> +#include <linux/gpio.h> +#include <linux/i2c.h> +#include <linux/input.h> +#include <linux/input/mt.h> +#include <linux/input/touchscreen.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> + +/* Per device data */ +struct hynitron_ts_platform_data { + unsigned int max_touch_num; + u32 ic_chkcode; + int (*firmware_info)(struct i2c_client *client); + int (*bootloader_enter)(struct i2c_client *client); + int (*init_input)(struct i2c_client *client); + void (*report_touch)(struct i2c_client *client); +}; + +/* Data generic to all (supported and non-supported) controllers. */ +struct hynitron_ts_data { + const struct hynitron_ts_platform_data *pdata; + struct i2c_client *client; + struct device *dev; + struct input_dev *input_dev; + struct touchscreen_properties prop; + struct gpio_desc *reset_gpio; + struct gpio_desc *irq_gpio; + u32 fw_version; +}; + +/* + * Hard coded reset delay value of 20ms not IC dependent in + * vendor driver. + */ +void hyn_reset_proc(struct i2c_client *client, int delay) +{ + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); + + gpiod_set_value(ts_data->reset_gpio, 1); + mdelay(20); + gpiod_set_value(ts_data->reset_gpio, 0); + if (delay) + mdelay(delay); +} + +static irqreturn_t hyn_interrupt_handler(int irq, void *dev_id) +{ + struct i2c_client *client = dev_id; + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); + + ts_data->pdata->report_touch(client); + + return IRQ_HANDLED; +} + +/* + * The vendor driver would retry twice before failing to read or write + * to the i2c device. + */ +int cst3xx_i2c_read(struct i2c_client *client, + unsigned char *buf, int len) +{ + int ret; + int retries = 0; + + while (retries < 2) { + ret = i2c_master_recv(client, buf, len); + if (ret <= 0) + retries++; + else + break; + } + + return ret; +} + +int cst3xx_i2c_write(struct i2c_client *client, + unsigned char *buf, int len) +{ + int ret; + int retries = 0; + + while (retries < 2) { + ret = i2c_master_send(client, buf, len); + if (ret <= 0) + retries++; + else + break; + } + + return ret; +} + +int cst3xx_i2c_read_register(struct i2c_client *client, + unsigned char *buf, int len) +{ + int ret; + + ret = cst3xx_i2c_write(client, buf, 2); + ret = cst3xx_i2c_read(client, buf, len); + + return ret; +} + +int cst3xx_firmware_info(struct i2c_client *client) +{ + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); + int ret; + u32 tmp; + unsigned char buf[4]; + + /* + * Testing suggests command is required to allow reading of + * firmware registers. + */ + buf[0] = 0xd1; + buf[1] = 0x01; + ret = cst3xx_i2c_write(client, buf, 2); + if (ret < 0) + return -EIO; + + mdelay(10); + + /* + * Read register for check-code to determine if device detected + * correctly. + */ + buf[0] = 0xd1; + buf[1] = 0xfc; + ret = cst3xx_i2c_read_register(client, buf, 4); + if (ret < 0) + return -EIO; + + memcpy(&tmp, buf, 4); + if ((le32_to_cpu(tmp) & 0xffff0000) != ts_data->pdata->ic_chkcode) { + dev_err(&client->dev, "%s ic mismatch\n", __func__); + return -ENODEV; + } + + mdelay(10); + + /* Read firmware version and test if firmware missing. */ + buf[0] = 0xd2; + buf[1] = 0x08; + ret = cst3xx_i2c_read_register(client, buf, 4); + if (ret < 0) + return -EIO; + + memcpy(&tmp, buf, 4); + + ts_data->fw_version = le32_to_cpu(tmp); + if (ts_data->fw_version == 0xa5a5a5a5) { + dev_err(&client->dev, "Device firmware missing\n"); + return -ENODEV; + } + + /* + * Testing suggests command required to exit register reading mode + * and allow device to function as touchscreen. + */ + buf[0] = 0xd1; + buf[1] = 0x09; + ret = cst3xx_i2c_write(client, buf, 2); + if (ret < 0) + return -EIO; + + mdelay(5); + + return 0; +} + +int cst3xx_bootloader_enter(struct i2c_client *client) +{ + int ret; + u8 retry; + unsigned char buf[4]; + + for (retry = 0; retry < 5; retry++) { + hyn_reset_proc(client, (7 + retry)); + /* set cmd to enter program mode */ + buf[0] = 0xa0; + buf[1] = 0x01; + buf[2] = 0xaa; + ret = cst3xx_i2c_write(client, buf, 3); + if (ret < 0) + continue; + mdelay(2); + + /* check whether in program mode */ + buf[0] = 0xa0; + buf[1] = 0x02; + ret = cst3xx_i2c_read_register(client, buf, 1); + + if (ret < 0) + continue; + + if (buf[0] == 0xac) + break; + } + + if (buf[0] != 0xac) { + dev_err(&client->dev, "%s unable to enter bootloader mode\n", + __func__); + return -ENODEV; + } + + hyn_reset_proc(client, 40); + + return 0; +} + +static void cst3xx_touch_update(struct hynitron_ts_data *ts_data, s32 id, + s32 x, s32 y, s32 w) +{ + input_mt_slot(ts_data->input_dev, id); + input_mt_report_slot_state(ts_data->input_dev, MT_TOOL_FINGER, 1); + touchscreen_report_pos(ts_data->input_dev, &ts_data->prop, x, y, true); + input_report_abs(ts_data->input_dev, ABS_MT_TOUCH_MAJOR, w); +} + +int cst3xx_finish_touch_read(struct i2c_client *client) +{ + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); + unsigned char buf[3]; + int ret; + + buf[0] = 0xd0; + buf[1] = 0x00; + buf[2] = 0xab; + ret = cst3xx_i2c_write(ts_data->client, buf, 3); + if (ret < 0) { + dev_err(ts_data->dev, "send read touch info ending failed.\n"); + return ret; + } + + return 0; +} + +/* + * Handle events from IRQ. Note that for cst3xx it appears that IRQ + * fires continuously while touched, otherwise once every 1500ms + * when not touched (assume touchscreen waking up periodically). + */ +static void cst3xx_touch_report(struct i2c_client *client) +{ + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); + unsigned char buf[30]; + unsigned char finger_id, sw; + unsigned int input_x = 0; + unsigned int input_y = 0; + unsigned int input_w = 0; + int idx = 0; + int i, ret; + int touch_cnt, i2c_len; + + buf[0] = 0xd0; + buf[1] = 0x00; + + /* Read and validate the first bits of input data. */ + ret = cst3xx_i2c_read_register(ts_data->client, buf, 7); + if ((ret < 0) || (buf[6] != 0xab) || (buf[0] == 0xab)) + goto end; + + touch_cnt = buf[5] & 0x7f; + + /* If no touches registered, clear the input slots. */ + if (touch_cnt == 0) { + input_mt_sync_frame(ts_data->input_dev); + input_sync(ts_data->input_dev); + return; + } + + /* + * If we have only one touch, we have enough data to process + * the event. If we have more than one touch we need to read + * the rest of the data. Note these functions are not combined + * because this is how it was done in the vendor driver and I + * lack the datasheet to modify the necessary values for + * reading from all the registers at once. + */ + if (touch_cnt > 1) { + buf[5] = 0xd0; + buf[6] = 0x07; + i2c_len = (touch_cnt - 1) * 5 + 1; + ret = cst3xx_i2c_read_register(ts_data->client, + &buf[5], i2c_len); + if (ret < 0) + goto end; + i2c_len += 5; + + if (buf[i2c_len - 1] != 0xab) + goto end; + } + + ret = cst3xx_finish_touch_read(client); + if (ret < 0) { + dev_err(ts_data->dev, "cst3xx touch read failure\n"); + return; + } + + for (i = 0; i < touch_cnt; i++) { + input_x = ((buf[idx + 1] << 4) | ((buf[idx + 3] >> 4) & 0x0f)); + input_y = ((buf[idx + 2] << 4) | (buf[idx + 3] & 0x0f)); + input_w = (buf[idx + 4] >> 3); + sw = (buf[idx] & 0x0f) >> 1; + finger_id = (buf[idx] >> 4) & 0x0f; + + /* Sanity check we don't have more fingers than we expect */ + if (ts_data->pdata->max_touch_num < finger_id) { + dev_err(ts_data->dev, "cst3xx touch read failure\n"); + break; + } + + /* sw value of 0 means no touch, 0x03 means touch */ + if (sw == 0x03) + cst3xx_touch_update(ts_data, finger_id, + input_x, input_y, input_w); + + idx += 5; + } + + input_mt_sync_frame(ts_data->input_dev); + input_sync(ts_data->input_dev); + return; +end: + cst3xx_finish_touch_read(client); + dev_err(ts_data->dev, "cst3xx touch read failure\n"); +} + +int cst3xx_input_dev_int(struct i2c_client *client) +{ + struct hynitron_ts_data *ts_data = i2c_get_clientdata(client); + int ret = 0; + + ts_data->input_dev = devm_input_allocate_device(&ts_data->client->dev); + if (!ts_data->input_dev) { + dev_err(&ts_data->client->dev, + "Failed to allocate input device.\n"); + return -ENOMEM; + } + + ts_data->input_dev->name = "Hynitron cst3xx Touchscreen"; + ts_data->input_dev->phys = "input/ts"; + ts_data->input_dev->id.bustype = BUS_I2C; + ts_data->input_dev->dev.parent = ts_data->dev; + + input_set_drvdata(ts_data->input_dev, ts_data); + + input_set_capability(ts_data->input_dev, EV_ABS, ABS_MT_POSITION_X); + input_set_capability(ts_data->input_dev, EV_ABS, ABS_MT_POSITION_Y); + input_set_abs_params(ts_data->input_dev, ABS_MT_TOUCH_MAJOR, + 0, 255, 0, 0); + + touchscreen_parse_properties(ts_data->input_dev, true, &ts_data->prop); + + if (!ts_data->prop.max_x || !ts_data->prop.max_y) { + dev_err(&ts_data->client->dev, + "Invalid x/y (%d, %d), using defaults\n", + ts_data->prop.max_x, ts_data->prop.max_y); + ts_data->prop.max_x = 1152; + ts_data->prop.max_y = 1920; + input_abs_set_max(ts_data->input_dev, + ABS_MT_POSITION_X, ts_data->prop.max_x); + input_abs_set_max(ts_data->input_dev, + ABS_MT_POSITION_Y, ts_data->prop.max_y); + } + + input_mt_init_slots(ts_data->input_dev, ts_data->pdata->max_touch_num, + INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); + + ret = input_register_device(ts_data->input_dev); + if (ret < 0) { + dev_err(&ts_data->client->dev, + "Input device registration failed\n"); + return ret; + } + + return ret; +} + +static int hyn_probe(struct i2c_client *client) +{ + struct hynitron_ts_data *ts_data; + int ret; + + ts_data = devm_kzalloc(&client->dev, sizeof(*ts_data), GFP_KERNEL); + if (!ts_data) + return -ENOMEM; + + ts_data->client = client; + ts_data->dev = &client->dev; + i2c_set_clientdata(client, ts_data); + + ts_data->reset_gpio = devm_gpiod_get(&client->dev, + "reset", GPIOD_OUT_LOW); + if (IS_ERR(ts_data->reset_gpio)) { + ret = PTR_ERR(ts_data->reset_gpio); + dev_err(&client->dev, "request reset gpio failed: %d\n", ret); + return ret; + } + + ts_data->pdata = of_device_get_match_data(&client->dev); + if (!ts_data->pdata) + return -EINVAL; + + hyn_reset_proc(client, 60); + + ret = ts_data->pdata->bootloader_enter(client); + if (ret < 0) + return ret; + + ret = ts_data->pdata->init_input(client); + if (ret < 0) + return ret; + + ret = ts_data->pdata->firmware_info(client); + if (ret < 0) + return ret; + + ret = devm_request_threaded_irq(&client->dev, client->irq, NULL, + hyn_interrupt_handler, + IRQF_ONESHOT, + "Hynitron Touch Int", client); + if (ret < 0) { + dev_err(&client->dev, "failed to request IRQ\n"); + return ret; + } + + return 0; +} + +static const struct hynitron_ts_platform_data cst3xx_data = { + .max_touch_num = 5, + .ic_chkcode = 0xcaca0000, + .firmware_info = &cst3xx_firmware_info, + .bootloader_enter = &cst3xx_bootloader_enter, + .init_input = &cst3xx_input_dev_int, + .report_touch = &cst3xx_touch_report, +}; + +static const struct i2c_device_id hyn_tpd_id[] = { + { .name = "hynitron_ts", 0 }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(i2c, hyn_tpd_id); + +static const struct of_device_id hyn_dt_match[] = { + { .compatible = "hynitron,cst3xx", .data = &cst3xx_data }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, hyn_dt_match); + +static struct i2c_driver hynitron_i2c_driver = { + .driver = { + .name = "Hynitron-TS", + .of_match_table = of_match_ptr(hyn_dt_match), + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + }, + .id_table = hyn_tpd_id, + .probe_new = hyn_probe, +}; + +module_i2c_driver(hynitron_i2c_driver); + +MODULE_AUTHOR("Chris Morgan"); +MODULE_DESCRIPTION("Hynitron Touchscreen Driver"); +MODULE_LICENSE("GPL");