[PATCH v2 2/2] Input: st1232 - add support for st1633
From: Martin Kepplinger
Date: Thu Jan 24 2019 - 05:21:46 EST
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:
www.ampdisplay.com/documents/pdf/AM-320480B6TZQW-TC0H.pdf
Signed-off-by: Martin Kepplinger <martin.kepplinger@xxxxxxxxxxxxx>
---
while this works, I'm not totally convinced by how the i2c path of probe
looks. what do you say?
thanks!
revision history
----------------
v2: use device_get_match_data(), invent an internal "have_z" bool property
v1: initial idea for the change
drivers/input/touchscreen/Kconfig | 6 +-
drivers/input/touchscreen/st1232.c | 126 ++++++++++++++++++++++-------
2 files changed, 98 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..f12ef666e2c8 100644
--- a/drivers/input/touchscreen/st1232.c
+++ b/drivers/input/touchscreen/st1232.c
@@ -18,18 +18,21 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
+#include <linux/of_device.h>
#include <linux/pm_qos.h>
#include <linux/slab.h>
#include <linux/types.h>
#define ST1232_TS_NAME "st1232-ts"
+#define ST1633_TS_NAME "st1633-ts"
+
+enum {
+ st1232,
+ st1633,
+};
#define MIN_X 0x00
#define MIN_Y 0x00
-#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 +41,24 @@ 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;
+ 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 +67,35 @@ 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 +114,14 @@ 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 +155,43 @@ 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 */
+ .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;
+
+ if (dev_fwnode(&client->dev))
+ match = device_get_match_data(&client->dev);
+ else if (id && id->driver_data == st1232)
+ match = &st1232_chip_info;
+ else if (id && id->driver_data == st1633)
+ match = &st1633_chip_info;
+ 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 +207,19 @@ 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);
+ 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 +249,14 @@ 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 +323,15 @@ 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, st1232 },
+ { ST1633_TS_NAME, st1633 },
{ }
};
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