AW: [PATCH 2/3] Input: st1232 - add support for st1633

From: Matthias Fend
Date: Tue Jan 29 2019 - 02:08:03 EST


Hi Martin,


Matthias Fend
R&D Electronics

Wolfvision GmbH
Oberes Ried 14 | 6833 Klaus | Austria
Tel: +43 5523 52250 | Mail: Matthias.Fend@xxxxxxxxxxxxxx

Webpage: www.wolfvision.com | www.wolfvision.com/green
Firmenbuch / Commercial Register: FN283521v Feldkirch/Austria

> -----Ursprüngliche Nachricht-----
> Von: linux-input-owner@xxxxxxxxxxxxxxx <linux-input-
> owner@xxxxxxxxxxxxxxx> Im Auftrag von Martin Kepplinger
> Gesendet: Montag, 28. Jänner 2019 20:10
> An: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
> Cc: devicetree@xxxxxxxxxxxxxxx; linux-input@xxxxxxxxxxxxxxx;
> robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> Martin Kepplinger <martin.kepplinger@xxxxxxxxxxxxx>
> Betreff: Re: [PATCH 2/3] Input: st1232 - add support for st1633
>
> Am 28.01.2019 20:03 schrieb Dmitry Torokhov:
> > Hi Martin,
> >
> > On Mon, Jan 28, 2019 at 09:44:48AM +0100, Martin Kepplinger wrote:
> >> From: Martin Kepplinger <martin.kepplinger@xxxxxxxxxxxxx>
> >>
> >> Add support for the Sitronix ST1633 touchscreen controller to the
> >> st1232
> >> driver. A protocol spec can be found here:
> >>
> https://emea01.safelinks.protection.outlook.com/?url=www.ampdisplay.co
> m%2Fdocuments%2Fpdf%2FAM-320480B6TZQW-
> TC0H.pdf&amp;data=01%7C01%7CMatthias.Fend%40wolfvision.net%7C4f9d
> 56475f674b1e3b4008d685543b35%7Ce94ec9da9183471e83b351baa8eb804f%
> 7C0&amp;sdata=YTw33BPKKpdN%2BBFrufVk8e4YqXOzR6VQKuzRMOjcwWk
> %3D&amp;reserved=0
> >>
> >> Signed-off-by: Martin Kepplinger <martin.kepplinger@xxxxxxxxxxxxx>
> >> ---
> >> drivers/input/touchscreen/Kconfig | 6 +-
> >> drivers/input/touchscreen/st1232.c | 122
> >> +++++++++++++++++++++--------
> >> 2 files changed, 94 insertions(+), 34 deletions(-)
> >>
> >> diff --git a/drivers/input/touchscreen/Kconfig
> >> b/drivers/input/touchscreen/Kconfig
> >> index 068dbbc610fc..7c597a49c265 100644
> >> --- a/drivers/input/touchscreen/Kconfig
> >> +++ b/drivers/input/touchscreen/Kconfig
> >> @@ -1168,11 +1168,11 @@ config TOUCHSCREEN_SIS_I2C
> >> module will be called sis_i2c.
> >>
> >> config TOUCHSCREEN_ST1232
> >> - tristate "Sitronix ST1232 touchscreen controllers"
> >> + tristate "Sitronix ST1232 or ST1633 touchscreen controllers"
> >> depends on I2C
> >> help
> >> - Say Y here if you want to support Sitronix ST1232
> >> - touchscreen controller.
> >> + Say Y here if you want to support the Sitronix ST1232
> >> + or ST1633 touchscreen controller.
> >>
> >> If unsure, say N.
> >>
> >> diff --git a/drivers/input/touchscreen/st1232.c
> >> b/drivers/input/touchscreen/st1232.c
> >> index 11ff32c68025..19a665d48dad 100644
> >> --- a/drivers/input/touchscreen/st1232.c
> >> +++ b/drivers/input/touchscreen/st1232.c
> >> @@ -23,13 +23,15 @@
> >> #include <linux/types.h>
> >>
> >> #define ST1232_TS_NAME "st1232-ts"
> >> +#define ST1633_TS_NAME "st1633-ts"
> >> +
> >> +enum {
> >> + st1232,
> >> + st1633,
> >> +};
> >
> > This enum seems no longer needed, I dropped it.
> >
> >>
> >> #define MIN_X 0x00
> >> #define MIN_Y 0x00
> >
> > Given we no longer have constant MAX_X/Y I simply used 0 in
> > input_set_abs_params() and dropped MIN-X/Y.
> >
> >> -#define MAX_X 0x31f /* (800 - 1) */
> >> -#define MAX_Y 0x1df /* (480 - 1) */
> >> -#define MAX_AREA 0xff
> >> -#define MAX_FINGERS 2
> >>
> >> struct st1232_ts_finger {
> >> u16 x;
> >> @@ -38,12 +40,24 @@ struct st1232_ts_finger {
> >> bool is_valid;
> >> };
> >>
> >> +struct st_chip_info {
> >> + bool have_z;
> >> + u16 max_x;
> >> + u16 max_y;
> >> + u16 max_area;
> >> + u16 max_fingers;
> >> + u8 start_reg;
> >> +};
> >> +
> >> struct st1232_ts_data {
> >> struct i2c_client *client;
> >> struct input_dev *input_dev;
> >> - struct st1232_ts_finger finger[MAX_FINGERS];
> >> struct dev_pm_qos_request low_latency_req;
> >> int reset_gpio;
> >
> > Could you please create an additional patch converting this to gpiod?
> > Instead of doing of_get_gpio()/gpio_is_valid()/devm_gpio_request()
> > smply
> > do
> >
> > ts->reset_gpio = devm_gpiod_get_optional();
> > if (IS_ERR(ts->reset_gpio)) {
> > ...
> > }
> >
> > and later
> >
> > if (ts->reset_gpio)
> > ...
> >
> > Looking at the code it looks like reset is as usual active low, so you
> > will need to invert the logic as gpiod takes care of convertion logical
> > value to proper level (active low or high).
>
> I'll test your applied changes and get back to this tomorrow.
>
> thanks.
>
> >
> >> + const struct st_chip_info *chip_info;
> >> + int read_buf_len;
> >> + u8 *read_buf;
> >> + struct st1232_ts_finger *finger;
> >> };
> >>
> >> static int st1232_ts_read_data(struct st1232_ts_data *ts)
> >> @@ -52,40 +66,35 @@ static int st1232_ts_read_data(struct
> >> st1232_ts_data *ts)
> >> struct i2c_client *client = ts->client;
> >> struct i2c_msg msg[2];
> >> int error;
> >> - u8 start_reg;
> >> - u8 buf[10];
> >> + int i, y;
> >> + u8 start_reg = ts->chip_info->start_reg;
> >> + u8 *buf = ts->read_buf;
> >>
> >> - /* read touchscreen data from ST1232 */
> >> + /* read touchscreen data */
> >> msg[0].addr = client->addr;
> >> msg[0].flags = 0;
> >> msg[0].len = 1;
> >> msg[0].buf = &start_reg;
> >> - start_reg = 0x10;
> >>
> >> msg[1].addr = ts->client->addr;
> >> msg[1].flags = I2C_M_RD;
> >> - msg[1].len = sizeof(buf);
> >> + msg[1].len = ts->read_buf_len;
> >> msg[1].buf = buf;
> >>
> >> error = i2c_transfer(client->adapter, msg, 2);
> >> if (error < 0)
> >> return error;
> >>
> >> - /* get "valid" bits */
> >> - finger[0].is_valid = buf[2] >> 7;
> >> - finger[1].is_valid = buf[5] >> 7;
> >> + for (i = 0, y = 0; i < ts->chip_info->max_fingers; i++, y += 3) {
> >> + finger[i].is_valid = buf[i + y] >> 7;
> >> + if (finger[i].is_valid) {
> >> + finger[i].x = ((buf[i + y] & 0x0070) << 4) | buf[i + 1];
> >> + finger[i].y = ((buf[i + y] & 0x0007) << 8) | buf[i + 2];
> >>
> >> - /* get xy coordinate */
> >> - if (finger[0].is_valid) {
> >> - finger[0].x = ((buf[2] & 0x0070) << 4) | buf[3];
> >> - finger[0].y = ((buf[2] & 0x0007) << 8) | buf[4];
> >> - finger[0].t = buf[8];
> >> - }
> >> -
> >> - if (finger[1].is_valid) {
> >> - finger[1].x = ((buf[5] & 0x0070) << 4) | buf[6];
> >> - finger[1].y = ((buf[5] & 0x0007) << 8) | buf[7];
> >> - finger[1].t = buf[9];
> >> + /* st1232 includes a z-axis / touch strength */
> >> + if (ts->chip_info->have_z)
> >> + finger[i].t = buf[i + 6];
> >> + }
> >> }
> >>
> >> return 0;
> >> @@ -104,11 +113,14 @@ static irqreturn_t st1232_ts_irq_handler(int
> >> irq, void *dev_id)
> >> goto end;
> >>
> >> /* multi touch protocol */
> >> - for (i = 0; i < MAX_FINGERS; i++) {
> >> + for (i = 0; i < ts->chip_info->max_fingers; i++) {
> >> if (!finger[i].is_valid)
> >> continue;
> >>
> >> - input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR,
> finger[i].t);
> >> + if (ts->chip_info->have_z)
> >> + input_report_abs(input_dev,
> ABS_MT_TOUCH_MAJOR,
> >> + finger[i].t);
> >> +
> >> input_report_abs(input_dev, ABS_MT_POSITION_X,
> finger[i].x);
> >> input_report_abs(input_dev, ABS_MT_POSITION_Y,
> finger[i].y);
> >> input_mt_sync(input_dev);
> >> @@ -142,12 +154,40 @@ static void st1232_ts_power(struct
> >> st1232_ts_data *ts, bool poweron)
> >> gpio_direction_output(ts->reset_gpio, poweron);
> >> }
> >>
> >> +static const struct st_chip_info st1232_chip_info = {
> >> + .have_z = true,
> >> + .max_x = 0x31f, /* 800 - 1 */
> >> + .max_y = 0x1df, /* 480 -1 */
> >> + .max_area = 0xff,
> >> + .max_fingers = 2,
> >> + .start_reg = 0x12,
> >> +};
> >> +
> >> +static const struct st_chip_info st1633_chip_info = {
> >> + .have_z = false,
> >> + .max_x = 0x13f, /* 320 - 1 */
> >> + .max_y = 0x1df, /* 480 -1 */

I guess these values are the dimensions of the referenced TFT display and not any limits of the touch controller. I wonder which values are correct here?
Maybe it would also be easier to just use the decimal representation and drop the comment, what do you think?

Thanks,
~Matthias

> >> + .max_area = 0x00,
> >> + .max_fingers = 5,
> >> + .start_reg = 0x12,
> >> +};
> >> +
> >> static int st1232_ts_probe(struct i2c_client *client,
> >> const struct i2c_device_id *id)
> >> {
> >> struct st1232_ts_data *ts;
> >> + struct st1232_ts_finger *finger;
> >> struct input_dev *input_dev;
> >> int error;
> >> + const struct st_chip_info *match = NULL;
> >
> > There is no need to initialize with NULL given that we do unconditional
> > assignment below. I removed initialization.
> >
> >> +
> >> + match = device_get_match_data(&client->dev);
> >> + if (!match && id)
> >> + match = (const void *)id->driver_data;
> >> + if (!match) {
> >> + dev_err(&client->dev, "unknown device model\n");
> >> + return -ENODEV;
> >> + }
> >>
> >> if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
> >> dev_err(&client->dev, "need I2C_FUNC_I2C\n");
> >> @@ -163,6 +203,19 @@ static int st1232_ts_probe(struct i2c_client
> >> *client,
> >> if (!ts)
> >> return -ENOMEM;
> >>
> >> + ts->chip_info = match;
> >> + ts->finger = devm_kzalloc(&client->dev,
> >> + sizeof(*finger) * ts->chip_info-
> >max_fingers,
> >> + GFP_KERNEL);
> >
> > I replaced it with devm_kcalloc(&client->dev,
> > ts->chip_info->max_fingers, sizeof(*finger),
> > GFP_KERNEL);
> >
> > and applied.
> >
> >> + if (!ts->finger)
> >> + return -ENOMEM;
> >> +
> >> + /* allocate a buffer according to the number of registers to read */
> >> + ts->read_buf_len = ts->chip_info->max_fingers * 4;
> >> + ts->read_buf = devm_kzalloc(&client->dev, ts->read_buf_len,
> >> GFP_KERNEL);
> >> + if (!ts->read_buf)
> >> + return -ENOMEM;
> >> +
> >> input_dev = devm_input_allocate_device(&client->dev);
> >> if (!input_dev)
> >> return -ENOMEM;
> >> @@ -192,9 +245,14 @@ static int st1232_ts_probe(struct i2c_client
> >> *client,
> >> __set_bit(EV_KEY, input_dev->evbit);
> >> __set_bit(EV_ABS, input_dev->evbit);
> >>
> >> - input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0,
> MAX_AREA, 0,
> >> 0);
> >> - input_set_abs_params(input_dev, ABS_MT_POSITION_X, MIN_X,
> MAX_X, 0,
> >> 0);
> >> - input_set_abs_params(input_dev, ABS_MT_POSITION_Y, MIN_Y,
> MAX_Y, 0,
> >> 0);
> >> + if (ts->chip_info->have_z)
> >> + input_set_abs_params(input_dev,
> ABS_MT_TOUCH_MAJOR, 0,
> >> + ts->chip_info->max_area, 0, 0);
> >> +
> >> + input_set_abs_params(input_dev, ABS_MT_POSITION_X,
> >> + MIN_X, ts->chip_info->max_x, 0, 0);
> >> + input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
> >> + MIN_Y, ts->chip_info->max_y, 0, 0);
> >>
> >> error = devm_request_threaded_irq(&client->dev, client->irq,
> >> NULL, st1232_ts_irq_handler,
> >> @@ -261,13 +319,15 @@ static
> SIMPLE_DEV_PM_OPS(st1232_ts_pm_ops,
> >> st1232_ts_suspend, st1232_ts_resume);
> >>
> >> static const struct i2c_device_id st1232_ts_id[] = {
> >> - { ST1232_TS_NAME, 0 },
> >> + { ST1232_TS_NAME, (unsigned long)&st1232_chip_info },
> >> + { ST1633_TS_NAME, (unsigned long)&st1633_chip_info },
> >> { }
> >> };
> >> MODULE_DEVICE_TABLE(i2c, st1232_ts_id);
> >>
> >> static const struct of_device_id st1232_ts_dt_ids[] = {
> >> - { .compatible = "sitronix,st1232", },
> >> + { .compatible = "sitronix,st1232", .data = &st1232_chip_info },
> >> + { .compatible = "sitronix,st1633", .data = &st1633_chip_info },
> >> { }
> >> };
> >> MODULE_DEVICE_TABLE(of, st1232_ts_dt_ids);
> >> --
> >> 2.20.1
> >>
> >
> > Thanks.