Input: st1232 - add support for st1633

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@ginzinger.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/Documentation/devicetree/bindings/input/touchscreen/sitronix-st1232.txt b/Documentation/devicetree/bindings/input/touchscreen/sitronix-st1232.txt
index 64ad48b..e73e826 100644 (file)
--- a/Documentation/devicetree/bindings/input/touchscreen/sitronix-st1232.txt
+++ b/Documentation/devicetree/bindings/input/touchscreen/sitronix-st1232.txt
@@ -1,7 +1,9 @@
-* Sitronix st1232 touchscreen controller
+* Sitronix st1232 or st1633 touchscreen controller
 
 Required properties:
-- compatible: must be "sitronix,st1232"
+- compatible: must contain one of
+  * "sitronix,st1232"
+  * "sitronix,st1633"
 - reg: I2C address of the chip
 - interrupts: interrupt to which the chip is connected
 

diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index af6027c..6c16aae 100644 (file)
--- 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 11ff32c..777df90 100644 (file)
--- a/drivers/input/touchscreen/st1232.c
+++ b/drivers/input/touchscreen/st1232.c
@@ -23,13 +23,7 @@
 #include <linux/types.h>
 
 #define ST1232_TS_NAME "st1232-ts"
-
-#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
+#define ST1633_TS_NAME "st1633-ts"
 
 struct st1232_ts_finger {
        u16 x;
@@ -38,12 +32,24 @@ 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 +58,35 @@ 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;
-
-       /* 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];
-       }
+       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];
 
-       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 +105,14 @@ 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);
@@ -142,13 +146,41 @@ 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)
 {
+       const struct st_chip_info *match;
        struct st1232_ts_data *ts;
+       struct st1232_ts_finger *finger;
        struct input_dev *input_dev;
        int error;
 
+       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");
                return -EIO;
@@ -163,6 +195,19 @@ static int st1232_ts_probe(struct i2c_client *client,
        if (!ts)
                return -ENOMEM;
 
+       ts->chip_info = match;
+       ts->finger = devm_kcalloc(&client->dev,
+                                 ts->chip_info->max_fingers, sizeof(*finger),
+                                 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 +237,14 @@ 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,
+                            0, ts->chip_info->max_x, 0, 0);
+       input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
+                            0, ts->chip_info->max_y, 0, 0);
 
        error = devm_request_threaded_irq(&client->dev, client->irq,
                                          NULL, st1232_ts_irq_handler,
@@ -261,13 +311,15 @@ 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);