Input: improve parsing OF parameters for touchscreens

When applying touchscreen parameters specified in device tree let's make
sure we keep whatever setup was done by the driver and not reset the
missing values to zero.

Reported-by: Pavel Machek <pavel@ucw.cz>
Tested-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/drivers/input/touchscreen/edt-ft5x06.c b/drivers/input/touchscreen/edt-ft5x06.c
index 29d179a1953b0bd2d9d7e2e628fb4c86dd351528..394b1de9a2a3fc7d955861ce6666093c8c8dcb4d 100644 (file)
--- a/drivers/input/touchscreen/edt-ft5x06.c
+++ b/drivers/input/touchscreen/edt-ft5x06.c
@@ -1041,7 +1041,7 @@ static int edt_ft5x06_ts_probe(struct i2c_client *client,
                             0, tsdata->num_y * 64 - 1, 0, 0);
 
        if (!pdata)
-               touchscreen_parse_of_params(input);
+               touchscreen_parse_of_params(input, true);
 
        error = input_mt_init_slots(input, MAX_SUPPORT_POINTS, INPUT_MT_DIRECT);
        if (error) {

diff --git a/drivers/input/touchscreen/of_touchscreen.c b/drivers/input/touchscreen/of_touchscreen.c
index b82b5207c78bdd3597af9f3abd11215abbaf9c2e..806cd0ad160f95c9b08e0bc4f9e9a33e2655f8bc 100644 (file)
--- a/drivers/input/touchscreen/of_touchscreen.c
+++ b/drivers/input/touchscreen/of_touchscreen.c
@@ -14,14 +14,22 @@
 #include <linux/input/mt.h>
 #include <linux/input/touchscreen.h>
 
-static u32 of_get_optional_u32(struct device_node *np,
-                              const char *property)
+static bool touchscreen_get_prop_u32(struct device_node *np,
+                                    const char *property,
+                                    unsigned int default_value,
+                                    unsigned int *value)
 {
-       u32 val = 0;
+       u32 val;
+       int error;
 
-       of_property_read_u32(np, property, &val);
+       error = of_property_read_u32(np, property, &val);
+       if (error) {
+               *value = default_value;
+               return false;
+       }
 
-       return val;
+       *value = val;
+       return true;
 }
 
 static void touchscreen_set_params(struct input_dev *dev,
@@ -54,34 +62,45 @@ static void touchscreen_set_params(struct input_dev *dev,
  * input device accordingly. The function keeps previously setuped default
  * values if no value is specified via DT.
  */
-void touchscreen_parse_of_params(struct input_dev *dev)
+void touchscreen_parse_of_params(struct input_dev *dev, bool multitouch)
 {
        struct device_node *np = dev->dev.parent->of_node;
-       u32 maximum, fuzz;
+       unsigned int axis;
+       unsigned int maximum, fuzz;
+       bool data_present;
 
        input_alloc_absinfo(dev);
        if (!dev->absinfo)
                return;
 
-       maximum = of_get_optional_u32(np, "touchscreen-size-x");
-       fuzz = of_get_optional_u32(np, "touchscreen-fuzz-x");
-       if (maximum || fuzz) {
-               touchscreen_set_params(dev, ABS_X, maximum, fuzz);
-               touchscreen_set_params(dev, ABS_MT_POSITION_X, maximum, fuzz);
-       }
+       axis = multitouch ? ABS_MT_POSITION_X : ABS_X;
+       data_present = touchscreen_get_prop_u32(np, "touchscreen-size-x",
+                                               input_abs_get_max(dev, axis),
+                                               &maximum) |
+                      touchscreen_get_prop_u32(np, "touchscreen-fuzz-x",
+                                               input_abs_get_fuzz(dev, axis),
+                                               &fuzz);
+       if (data_present)
+               touchscreen_set_params(dev, axis, maximum, fuzz);
 
-       maximum = of_get_optional_u32(np, "touchscreen-size-y");
-       fuzz = of_get_optional_u32(np, "touchscreen-fuzz-y");
-       if (maximum || fuzz) {
-               touchscreen_set_params(dev, ABS_Y, maximum, fuzz);
-               touchscreen_set_params(dev, ABS_MT_POSITION_Y, maximum, fuzz);
-       }
+       axis = multitouch ? ABS_MT_POSITION_Y : ABS_Y;
+       data_present = touchscreen_get_prop_u32(np, "touchscreen-size-y",
+                                               input_abs_get_max(dev, axis),
+                                               &maximum) |
+                      touchscreen_get_prop_u32(np, "touchscreen-fuzz-y",
+                                               input_abs_get_fuzz(dev, axis),
+                                               &fuzz);
+       if (data_present)
+               touchscreen_set_params(dev, axis, maximum, fuzz);
 
-       maximum = of_get_optional_u32(np, "touchscreen-max-pressure");
-       fuzz = of_get_optional_u32(np, "touchscreen-fuzz-pressure");
-       if (maximum || fuzz) {
-               touchscreen_set_params(dev, ABS_PRESSURE, maximum, fuzz);
-               touchscreen_set_params(dev, ABS_MT_PRESSURE, maximum, fuzz);
-       }
+       axis = multitouch ? ABS_MT_PRESSURE : ABS_PRESSURE;
+       data_present = touchscreen_get_prop_u32(np, "touchscreen-max-pressure",
+                                               input_abs_get_max(dev, axis),
+                                               &maximum) |
+                      touchscreen_get_prop_u32(np, "touchscreen-fuzz-pressure",
+                                               input_abs_get_fuzz(dev, axis),
+                                               &fuzz);
+       if (data_present)
+               touchscreen_set_params(dev, axis, maximum, fuzz);
 }
 EXPORT_SYMBOL(touchscreen_parse_of_params);

diff --git a/drivers/input/touchscreen/tsc2005.c b/drivers/input/touchscreen/tsc2005.c
index 72657c5794303d6c7a2a7b251e848046ec674210..d8c025b0f88cd4fe2c16712d1852111d782e08da 100644 (file)
--- a/drivers/input/touchscreen/tsc2005.c
+++ b/drivers/input/touchscreen/tsc2005.c
@@ -709,7 +709,7 @@ static int tsc2005_probe(struct spi_device *spi)
        input_set_abs_params(input_dev, ABS_PRESSURE, 0, max_p, fudge_p, 0);
 
        if (np)
-               touchscreen_parse_of_params(input_dev);
+               touchscreen_parse_of_params(input_dev, false);
 
        input_dev->open = tsc2005_open;
        input_dev->close = tsc2005_close;

diff --git a/include/linux/input/touchscreen.h b/include/linux/input/touchscreen.h
index 08a5ef6e8f25a485f0af16b35e3ba1d066ccc6d2..eecc9ea6cd58716f7e4d2597f4f5699ad818d546 100644 (file)
--- a/include/linux/input/touchscreen.h
+++ b/include/linux/input/touchscreen.h
@@ -12,9 +12,10 @@
 #include <linux/input.h>
 
 #ifdef CONFIG_OF
-void touchscreen_parse_of_params(struct input_dev *dev);
+void touchscreen_parse_of_params(struct input_dev *dev, bool multitouch);
 #else
-static inline void touchscreen_parse_of_params(struct input_dev *dev)
+static inline void touchscreen_parse_of_params(struct input_dev *dev,
+                                              bool multitouch)
 {
 }
 #endif