Re: [PATCH] input : wacom - report resolution for ABS_MT events

["Henrik Rydberg" <rydberg@euromail.se>]

Hi Ping,

> This is mainly required by the serial pen and touch devices since
> both pen and touch are on the same port. Updated the USB ones to
> keep MT event definition consistent among serial and USB devices.

Why is this change performed? What does the patch do? Please elaborate
a little bit.

> 
> Signed-off-by: Ping Cheng <pingc@wacom.com>
> ---
>  drivers/input/tablet/wacom_wac.c        |    6 ++++++
>  drivers/input/touchscreen/wacom_w8001.c |   23 ++++++++++++++++++++++-
>  2 files changed, 28 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/input/tablet/wacom_wac.c b/drivers/input/tablet/wacom_wac.c
> index 367fa82..f129440 100644
> --- a/drivers/input/tablet/wacom_wac.c
> +++ b/drivers/input/tablet/wacom_wac.c
> @@ -1283,6 +1283,12 @@ void wacom_setup_input_capabilities(struct input_dev *input_dev,
>  			input_set_abs_params(input_dev, ABS_MT_PRESSURE,
>  					     0, features->pressure_max,
>  					     features->pressure_fuzz, 0);
> +			input_abs_set_res(input_dev, ABS_MT_POSITION_X,
> +				wacom_calculate_touch_res(features->x_max,
> +							features->x_phy));
> +			input_abs_set_res(input_dev, ABS_MT_POSITION_Y,
> +				wacom_calculate_touch_res(features->y_max,
> +							features->y_phy));

Is this for the BAMBOO_PT case? What about the extra x/y scaling for
some of those devices?

>  			input_abs_set_res(input_dev, ABS_X,
>  				wacom_calculate_touch_res(features->x_max,
>  							features->x_phy));
> diff --git a/drivers/input/touchscreen/wacom_w8001.c b/drivers/input/touchscreen/wacom_w8001.c
> index 5cb8449..f54da5c 100644
> --- a/drivers/input/touchscreen/wacom_w8001.c
> +++ b/drivers/input/touchscreen/wacom_w8001.c
> @@ -51,6 +51,11 @@ MODULE_LICENSE("GPL");
>  #define W8001_PKTLEN_TPCCTL	11	/* control packet */
>  #define W8001_PKTLEN_TOUCH2FG	13
>  
> +/* resolution in points/mm */
> +#define W8001_PEN_RESOLUTION    100
> +#define W8001_TOUCH_RESOLUTION  10
> +
> +
>  struct w8001_coord {
>  	u8 rdy;
>  	u8 tsw;
> @@ -92,6 +97,8 @@ struct w8001 {
>  	u16 max_touch_y;
>  	u16 max_pen_x;
>  	u16 max_pen_y;
> +	u16 touch_res_x;
> +	u16 touch_res_y;

Are these used anywhere?

>  	char name[64];
>  };
>  
> @@ -198,7 +205,7 @@ static void parse_touchquery(u8 *data, struct w8001_touch_query *query)
>  		query->y = 1024;
>  		if (query->panel_res)
>  			query->x = query->y = (1 << query->panel_res);
> -		query->panel_res = 10;
> +		query->panel_res = W8001_TOUCH_RESOLUTION;
>  	}
>  }
>  
> @@ -394,6 +401,8 @@ static int w8001_setup(struct w8001 *w8001)
>  
>  		input_set_abs_params(dev, ABS_X, 0, coord.x, 0, 0);
>  		input_set_abs_params(dev, ABS_Y, 0, coord.y, 0, 0);
> +		input_abs_set_res(dev, ABS_X, W8001_PEN_RESOLUTION);
> +		input_abs_set_res(dev, ABS_Y, W8001_PEN_RESOLUTION);
>  		input_set_abs_params(dev, ABS_PRESSURE, 0, coord.pen_pressure, 0, 0);
>  		if (coord.tilt_x && coord.tilt_y) {
>  			input_set_abs_params(dev, ABS_TILT_X, 0, coord.tilt_x, 0, 0);
> @@ -411,6 +420,9 @@ static int w8001_setup(struct w8001 *w8001)
>  	 * second byte is empty, which indicates touch is not supported.
>  	 */
>  	if (!error && w8001->response[1]) {
> +		u16 touch_res_x  = touch.panel_res;
> +		u16 touch_res_y = touch.panel_res;
> +
>  		__set_bit(BTN_TOUCH, dev->keybit);
>  		__set_bit(BTN_TOOL_FINGER, dev->keybit);
>  
> @@ -422,10 +434,17 @@ static int w8001_setup(struct w8001 *w8001)
>  		if (w8001->max_pen_x && w8001->max_pen_y) {
>  			touch.x = w8001->max_pen_x;
>  			touch.y = w8001->max_pen_y;
> +
> +			/* scale resolution as well */
> +			touch_res_x *= w8001->max_pen_x / w8001->max_touch_x;
> +			touch_res_y *= w8001->max_pen_y / w8001->max_touch_y;
>  		}
>  
>  		input_set_abs_params(dev, ABS_X, 0, touch.x, 0, 0);
>  		input_set_abs_params(dev, ABS_Y, 0, touch.y, 0, 0);
> +		/* don't report touch resolution for ST since pen resolution
> +		 * is more important
> +		 */
>  
>  		switch (touch.sensor_id) {
>  		case 0:
> @@ -453,6 +472,8 @@ static int w8001_setup(struct w8001 *w8001)
>  						0, touch.y, 0, 0);
>  			input_set_abs_params(dev, ABS_MT_TOOL_TYPE,
>  						0, MT_TOOL_MAX, 0, 0);
> +			input_abs_set_res(dev, ABS_MT_POSITION_X, touch_res_x);
> +			input_abs_set_res(dev, ABS_MT_POSITION_Y, touch_res_y);
>  
>  			strlcat(w8001->name, " 2FG", sizeof(w8001->name));
>  			if (w8001->max_pen_x && w8001->max_pen_y)
> -- 
> 1.7.3.5
> 

Thanks,
Henrik