Re: [PATCH v3 3/3] Input: goodix - use generic touchscreen_properties

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

Hi Marcin,

On Thu, Jan 25, 2018 at 08:08:29PM +0100, Marcin Niestroj wrote:
> Use touchscreen_properties structure instead of implementing all
> properties by our own. It allows us to reuse generic code for parsing
> device-tree properties (which was implemented manually in the driver
> for now). Additionally, it allows us to report events using generic
> touchscreen_report_pos(), which automatically handles inverted and
> swapped axes.
> 
> Developed and tested on custom DT-based device with gt1151 touch
> panel.
> 
> Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
> ---
> Changes v2 -> v3 (suggested by Bastien):
>  - fix commit description
> 
> Changes v1 -> v2:
>  - rebased on patches 1 and 2 in series
>  - added description of test board in changelog (suggested by Bastien)
> 
>  drivers/input/touchscreen/goodix.c | 93 ++++++++++++++------------------------
>  1 file changed, 33 insertions(+), 60 deletions(-)
> 
> diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
> index dc832890f6d3..f82101cd9c04 100644
> --- a/drivers/input/touchscreen/goodix.c
> +++ b/drivers/input/touchscreen/goodix.c
> @@ -22,6 +22,7 @@
>  #include <linux/i2c.h>
>  #include <linux/input.h>
>  #include <linux/input/mt.h>
> +#include <linux/input/touchscreen.h>
>  #include <linux/module.h>
>  #include <linux/delay.h>
>  #include <linux/irq.h>
> @@ -43,11 +44,7 @@ struct goodix_ts_data {
>  	struct i2c_client *client;
>  	struct input_dev *input_dev;
>  	const struct goodix_chip_data *chip;
> -	int abs_x_max;
> -	int abs_y_max;
> -	bool swapped_x_y;
> -	bool inverted_x;
> -	bool inverted_y;
> +	struct touchscreen_properties prop;
>  	unsigned int max_touch_num;
>  	unsigned int int_trigger_type;
>  	struct gpio_desc *gpiod_int;
> @@ -295,24 +292,10 @@ static void goodix_ts_report_touch(struct goodix_ts_data *ts, u8 *coor_data)
>  	int input_y = get_unaligned_le16(&coor_data[3]);
>  	int input_w = get_unaligned_le16(&coor_data[5]);
>  
> -	/* Inversions have to happen before axis swapping */
> -	if (!ts->swapped_x_y) {
> -		if (ts->inverted_x)
> -			input_x = ts->abs_x_max - input_x;
> -		if (ts->inverted_y)
> -			input_y = ts->abs_y_max - input_y;
> -	} else {
> -		if (ts->inverted_x)
> -			input_x = ts->abs_y_max - input_x;
> -		if (ts->inverted_y)
> -			input_y = ts->abs_x_max - input_y;
> -		swap(input_x, input_y);
> -	}
> -
>  	input_mt_slot(ts->input_dev, id);
>  	input_mt_report_slot_state(ts->input_dev, MT_TOOL_FINGER, true);
> -	input_report_abs(ts->input_dev, ABS_MT_POSITION_X, input_x);
> -	input_report_abs(ts->input_dev, ABS_MT_POSITION_Y, input_y);
> +	touchscreen_report_pos(ts->input_dev, &ts->prop, input_x, input_y,
> +			true);
>  	input_report_abs(ts->input_dev, ABS_MT_TOUCH_MAJOR, input_w);
>  	input_report_abs(ts->input_dev, ABS_MT_WIDTH_MAJOR, input_w);
>  }
> @@ -585,6 +568,7 @@ static int goodix_get_gpio_config(struct goodix_ts_data *ts)
>  static void goodix_read_config(struct goodix_ts_data *ts)
>  {
>  	u8 config[GOODIX_CONFIG_MAX_LENGTH];
> +	int x_max, y_max;
>  	int error;
>  
>  	error = goodix_i2c_read(ts->client, ts->chip->config_addr,
> @@ -593,37 +577,34 @@ static void goodix_read_config(struct goodix_ts_data *ts)
>  		dev_warn(&ts->client->dev,
>  			 "Error reading config (%d), using defaults\n",
>  			 error);
> -		ts->abs_x_max = GOODIX_MAX_WIDTH - 1;
> -		ts->abs_y_max = GOODIX_MAX_HEIGHT - 1;
> -		if (ts->swapped_x_y)
> -			swap(ts->abs_x_max, ts->abs_y_max);
> +		x_max = GOODIX_MAX_WIDTH;
> +		y_max = GOODIX_MAX_HEIGHT;
>  		ts->int_trigger_type = GOODIX_INT_TRIGGER;
>  		ts->max_touch_num = GOODIX_MAX_CONTACTS;
> -		return;
> +		goto input_set_params;
>  	}
>  
> -	ts->abs_x_max = get_unaligned_le16(&config[RESOLUTION_LOC]) - 1;
> -	ts->abs_y_max = get_unaligned_le16(&config[RESOLUTION_LOC + 2]) - 1;
> -	if (ts->swapped_x_y)
> -		swap(ts->abs_x_max, ts->abs_y_max);
> +	x_max = get_unaligned_le16(&config[RESOLUTION_LOC]);
> +	y_max = get_unaligned_le16(&config[RESOLUTION_LOC + 2]);
>  	ts->int_trigger_type = config[TRIGGER_LOC] & 0x03;
>  	ts->max_touch_num = config[MAX_CONTACTS_LOC] & 0x0f;
> -	if (!ts->abs_x_max || !ts->abs_y_max || !ts->max_touch_num) {
> +	if (!x_max || !y_max || !ts->max_touch_num) {
>  		dev_err(&ts->client->dev,
>  			"Invalid config, using defaults\n");
> -		ts->abs_x_max = GOODIX_MAX_WIDTH - 1;
> -		ts->abs_y_max = GOODIX_MAX_HEIGHT - 1;
> -		if (ts->swapped_x_y)
> -			swap(ts->abs_x_max, ts->abs_y_max);
> +		x_max = GOODIX_MAX_WIDTH;
> +		y_max = GOODIX_MAX_HEIGHT;
>  		ts->max_touch_num = GOODIX_MAX_CONTACTS;
>  	}
>  
> -	if (dmi_check_system(rotated_screen)) {
> -		ts->inverted_x = true;
> -		ts->inverted_y = true;
> -		dev_dbg(&ts->client->dev,
> -			 "Applying '180 degrees rotated screen' quirk\n");
> -	}
> +input_set_params:
> +	input_set_abs_params(ts->input_dev, ABS_MT_POSITION_X,
> +			0, x_max - 1, 0, 0);
> +	input_set_abs_params(ts->input_dev, ABS_MT_POSITION_Y,
> +			0, y_max - 1, 0, 0);
> +	input_set_abs_params(ts->input_dev, ABS_MT_WIDTH_MAJOR, 0, 255, 0, 0);
> +	input_set_abs_params(ts->input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
> +	input_mt_init_slots(ts->input_dev, ts->max_touch_num,
> +			INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
>  }
>  
>  /**
> @@ -698,16 +679,6 @@ static int goodix_request_input_dev(struct goodix_ts_data *ts)
>  		return -ENOMEM;
>  	}
>  
> -	input_set_abs_params(ts->input_dev, ABS_MT_POSITION_X,
> -			     0, ts->abs_x_max, 0, 0);
> -	input_set_abs_params(ts->input_dev, ABS_MT_POSITION_Y,
> -			     0, ts->abs_y_max, 0, 0);
> -	input_set_abs_params(ts->input_dev, ABS_MT_WIDTH_MAJOR, 0, 255, 0, 0);
> -	input_set_abs_params(ts->input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
> -
> -	input_mt_init_slots(ts->input_dev, ts->max_touch_num,
> -			    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
> -
>  	ts->input_dev->name = "Goodix Capacitive TouchScreen";
>  	ts->input_dev->phys = "input/ts";
>  	ts->input_dev->id.bustype = BUS_I2C;
> @@ -742,19 +713,21 @@ static int goodix_configure_dev(struct goodix_ts_data *ts)
>  {
>  	int error;
>  
> -	ts->swapped_x_y = device_property_read_bool(&ts->client->dev,
> -						    "touchscreen-swapped-x-y");
> -	ts->inverted_x = device_property_read_bool(&ts->client->dev,
> -						   "touchscreen-inverted-x");
> -	ts->inverted_y = device_property_read_bool(&ts->client->dev,
> -						   "touchscreen-inverted-y");
> -
> -	goodix_read_config(ts);
> -
>  	error = goodix_request_input_dev(ts);
>  	if (error)
>  		return error;
>  
> +	goodix_read_config(ts);
> +
> +	touchscreen_parse_properties(ts->input_dev, true, &ts->prop);

You want to do reading of the config and parsing properties and applying
them to the input device before input device is registered. Actually,
you want to do that before you call input_mt_init_slots() to make sure
multitouch and single-touch data is consistend (ABS_MT_POSITION_X/Y vs
ABS_X/Y).

Can you please try the version below (note that I sqashed all your 3
patches in one as, as I mentioed, I do not see why they need to be split
in the first place).

Thanks.

-- 
Dmitry


Input: goodix - use generic touchscreen_properties

From: Marcin Niestroj <m.niestroj@grinn-global.com>

Use touchscreen_properties structure instead of implementing all
properties by our own. It allows us to reuse generic code for parsing
device-tree properties (which was implemented manually in the driver for
now). Additionally, it allows us to report events using generic
touchscreen_report_pos(), which automatically handles inverted and
swapped axes.

This fixes the issue with the custom code incorrectly handling case where
ts->inverted_x and ts->swapped_x_y were true, but ts->inverted_y was
false. Assuming we have 720x1280 touch panel, ts->abs_x_max == 1279 and
ts->abs_y_max == 719 (because we inverted that in goodix_read_config()).
Now let's assume that we received event from (0:0) position (in touch
panel original coordinates). In function goodix_ts_report_touch() we
calculate input_x as 1279, but after swapping input_y takes that value
(which is more that maximum 719 value reported during initialization).

Note that since touchscreen coordinates are 0-indexed, we now report
touchscreen range as (0:size-1).

Developed and tested on custom DT-based device with gt1151 touch
panel.

Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>
Patchwork-Id: 10184731
[dtor: fix endianness annotation reported by sparse, handle errors when
 initializing MT slots]
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/touchscreen/goodix.c |  141 +++++++++++++++---------------------
 1 file changed, 58 insertions(+), 83 deletions(-)

diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
index ecec8eb17f28b..9736c83dd418f 100644
--- a/drivers/input/touchscreen/goodix.c
+++ b/drivers/input/touchscreen/goodix.c
@@ -22,6 +22,7 @@
 #include <linux/i2c.h>
 #include <linux/input.h>
 #include <linux/input/mt.h>
+#include <linux/input/touchscreen.h>
 #include <linux/module.h>
 #include <linux/delay.h>
 #include <linux/irq.h>
@@ -43,11 +44,7 @@ struct goodix_ts_data {
 	struct i2c_client *client;
 	struct input_dev *input_dev;
 	const struct goodix_chip_data *chip;
-	int abs_x_max;
-	int abs_y_max;
-	bool swapped_x_y;
-	bool inverted_x;
-	bool inverted_y;
+	struct touchscreen_properties prop;
 	unsigned int max_touch_num;
 	unsigned int int_trigger_type;
 	struct gpio_desc *gpiod_int;
@@ -160,7 +157,7 @@ static int goodix_i2c_read(struct i2c_client *client,
 			   u16 reg, u8 *buf, int len)
 {
 	struct i2c_msg msgs[2];
-	u16 wbuf = cpu_to_be16(reg);
+	__be16 wbuf = cpu_to_be16(reg);
 	int ret;
 
 	msgs[0].flags = 0;
@@ -295,18 +292,10 @@ static void goodix_ts_report_touch(struct goodix_ts_data *ts, u8 *coor_data)
 	int input_y = get_unaligned_le16(&coor_data[3]);
 	int input_w = get_unaligned_le16(&coor_data[5]);
 
-	/* Inversions have to happen before axis swapping */
-	if (ts->inverted_x)
-		input_x = ts->abs_x_max - input_x;
-	if (ts->inverted_y)
-		input_y = ts->abs_y_max - input_y;
-	if (ts->swapped_x_y)
-		swap(input_x, input_y);
-
 	input_mt_slot(ts->input_dev, id);
 	input_mt_report_slot_state(ts->input_dev, MT_TOOL_FINGER, true);
-	input_report_abs(ts->input_dev, ABS_MT_POSITION_X, input_x);
-	input_report_abs(ts->input_dev, ABS_MT_POSITION_Y, input_y);
+	touchscreen_report_pos(ts->input_dev, &ts->prop,
+			       input_x, input_y, true);
 	input_report_abs(ts->input_dev, ABS_MT_TOUCH_MAJOR, input_w);
 	input_report_abs(ts->input_dev, ABS_MT_WIDTH_MAJOR, input_w);
 }
@@ -579,44 +568,27 @@ static int goodix_get_gpio_config(struct goodix_ts_data *ts)
 static void goodix_read_config(struct goodix_ts_data *ts)
 {
 	u8 config[GOODIX_CONFIG_MAX_LENGTH];
+	int x_max, y_max;
 	int error;
 
 	error = goodix_i2c_read(ts->client, ts->chip->config_addr,
 				config, ts->chip->config_len);
 	if (error) {
-		dev_warn(&ts->client->dev,
-			 "Error reading config (%d), using defaults\n",
+		dev_warn(&ts->client->dev, "Error reading config: %d\n",
 			 error);
-		ts->abs_x_max = GOODIX_MAX_WIDTH;
-		ts->abs_y_max = GOODIX_MAX_HEIGHT;
-		if (ts->swapped_x_y)
-			swap(ts->abs_x_max, ts->abs_y_max);
 		ts->int_trigger_type = GOODIX_INT_TRIGGER;
 		ts->max_touch_num = GOODIX_MAX_CONTACTS;
 		return;
 	}
 
-	ts->abs_x_max = get_unaligned_le16(&config[RESOLUTION_LOC]);
-	ts->abs_y_max = get_unaligned_le16(&config[RESOLUTION_LOC + 2]);
-	if (ts->swapped_x_y)
-		swap(ts->abs_x_max, ts->abs_y_max);
 	ts->int_trigger_type = config[TRIGGER_LOC] & 0x03;
 	ts->max_touch_num = config[MAX_CONTACTS_LOC] & 0x0f;
-	if (!ts->abs_x_max || !ts->abs_y_max || !ts->max_touch_num) {
-		dev_err(&ts->client->dev,
-			"Invalid config, using defaults\n");
-		ts->abs_x_max = GOODIX_MAX_WIDTH;
-		ts->abs_y_max = GOODIX_MAX_HEIGHT;
-		if (ts->swapped_x_y)
-			swap(ts->abs_x_max, ts->abs_y_max);
-		ts->max_touch_num = GOODIX_MAX_CONTACTS;
-	}
 
-	if (dmi_check_system(rotated_screen)) {
-		ts->inverted_x = true;
-		ts->inverted_y = true;
-		dev_dbg(&ts->client->dev,
-			 "Applying '180 degrees rotated screen' quirk\n");
+	x_max = get_unaligned_le16(&config[RESOLUTION_LOC]);
+	y_max = get_unaligned_le16(&config[RESOLUTION_LOC + 2]);
+	if (x_max && y_max) {
+		input_abs_set_max(ts->input_dev, ABS_MT_POSITION_X, x_max - 1);
+		input_abs_set_max(ts->input_dev, ABS_MT_POSITION_Y, y_max - 1);
 	}
 }
 
@@ -676,32 +648,28 @@ static int goodix_i2c_test(struct i2c_client *client)
 }
 
 /**
- * goodix_request_input_dev - Allocate, populate and register the input device
+ * goodix_configure_dev - Finish device initialization
  *
  * @ts: our goodix_ts_data pointer
  *
- * Must be called during probe
+ * Must be called from probe to finish initialization of the device.
+ * Contains the common initialization code for both devices that
+ * declare gpio pins and devices that do not. It is either called
+ * directly from probe or from request_firmware_wait callback.
  */
-static int goodix_request_input_dev(struct goodix_ts_data *ts)
+static int goodix_configure_dev(struct goodix_ts_data *ts)
 {
 	int error;
 
+	ts->int_trigger_type = GOODIX_INT_TRIGGER;
+	ts->max_touch_num = GOODIX_MAX_CONTACTS;
+
 	ts->input_dev = devm_input_allocate_device(&ts->client->dev);
 	if (!ts->input_dev) {
 		dev_err(&ts->client->dev, "Failed to allocate input device.");
 		return -ENOMEM;
 	}
 
-	input_set_abs_params(ts->input_dev, ABS_MT_POSITION_X,
-			     0, ts->abs_x_max, 0, 0);
-	input_set_abs_params(ts->input_dev, ABS_MT_POSITION_Y,
-			     0, ts->abs_y_max, 0, 0);
-	input_set_abs_params(ts->input_dev, ABS_MT_WIDTH_MAJOR, 0, 255, 0, 0);
-	input_set_abs_params(ts->input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
-
-	input_mt_init_slots(ts->input_dev, ts->max_touch_num,
-			    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
-
 	ts->input_dev->name = "Goodix Capacitive TouchScreen";
 	ts->input_dev->phys = "input/ts";
 	ts->input_dev->id.bustype = BUS_I2C;
@@ -712,42 +680,49 @@ static int goodix_request_input_dev(struct goodix_ts_data *ts)
 	/* Capacitive Windows/Home button on some devices */
 	input_set_capability(ts->input_dev, EV_KEY, KEY_LEFTMETA);
 
-	error = input_register_device(ts->input_dev);
-	if (error) {
-		dev_err(&ts->client->dev,
-			"Failed to register input device: %d", error);
-		return error;
-	}
+	input_set_capability(ts->input_dev, EV_ABS, ABS_MT_POSITION_X);
+	input_set_capability(ts->input_dev, EV_ABS, ABS_MT_POSITION_Y);
+	input_set_abs_params(ts->input_dev, ABS_MT_WIDTH_MAJOR, 0, 255, 0, 0);
+	input_set_abs_params(ts->input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
 
-	return 0;
-}
+	/* Read configuration and apply touchscreen parameters */
+	goodix_read_config(ts);
 
-/**
- * goodix_configure_dev - Finish device initialization
- *
- * @ts: our goodix_ts_data pointer
- *
- * Must be called from probe to finish initialization of the device.
- * Contains the common initialization code for both devices that
- * declare gpio pins and devices that do not. It is either called
- * directly from probe or from request_firmware_wait callback.
- */
-static int goodix_configure_dev(struct goodix_ts_data *ts)
-{
-	int error;
+	/* Try overriding touchscreen parameters via device properties */
+	touchscreen_parse_properties(ts->input_dev, true, &ts->prop);
 
-	ts->swapped_x_y = device_property_read_bool(&ts->client->dev,
-						    "touchscreen-swapped-x-y");
-	ts->inverted_x = device_property_read_bool(&ts->client->dev,
-						   "touchscreen-inverted-x");
-	ts->inverted_y = device_property_read_bool(&ts->client->dev,
-						   "touchscreen-inverted-y");
+	if (!ts->prop.max_x || !ts->prop.max_y || !ts->max_touch_num) {
+		dev_err(&ts->client->dev, "Invalid config, using defaults\n");
+		ts->prop.max_x = GOODIX_MAX_WIDTH - 1;
+		ts->prop.max_y = GOODIX_MAX_HEIGHT - 1;
+		ts->max_touch_num = GOODIX_MAX_CONTACTS;
+		input_abs_set_max(ts->input_dev,
+				  ABS_MT_POSITION_X, ts->prop.max_x);
+		input_abs_set_max(ts->input_dev,
+				  ABS_MT_POSITION_Y, ts->prop.max_y);
+	}
 
-	goodix_read_config(ts);
+	if (dmi_check_system(rotated_screen)) {
+		ts->prop.invert_x = true;
+		ts->prop.invert_y = true;
+		dev_dbg(&ts->client->dev,
+			"Applying '180 degrees rotated screen' quirk\n");
+	}
 
-	error = goodix_request_input_dev(ts);
-	if (error)
+	error = input_mt_init_slots(ts->input_dev, ts->max_touch_num,
+				    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
+	if (error) {
+		dev_err(&ts->client->dev,
+			"Failed to initialize MT slots: %d", error);
+		return error;
+	}
+
+	error = input_register_device(ts->input_dev);
+	if (error) {
+		dev_err(&ts->client->dev,
+			"Failed to register input device: %d", error);
 		return error;
+	}
 
 	ts->irq_flags = goodix_irq_flags[ts->int_trigger_type] | IRQF_ONESHOT;
 	error = goodix_request_irq(ts);