Input: wdt87xx_i2c - add a scaling factor for TOUCH_MAJOR event

Get the scaling factor when it reads the sys params. The width value will
multiple the factor and report the value in the TOUCH_MAJOR event.
Signed-off-by: HungNien Chen <hn.chen@weidahitech.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/touchscreen/wdt87xx_i2c.c

@@ -23,7 +23,7 @@
 #include <asm/unaligned.h>
 
 #define WDT87XX_NAME		"wdt87xx_i2c"
-#define WDT87XX_DRV_VER		"0.9.5"
+#define WDT87XX_DRV_VER		"0.9.6"
 #define WDT87XX_FW_NAME		"wdt87xx_fw.bin"
 #define WDT87XX_CFG_NAME	"wdt87xx_cfg.bin"
 
@@ -83,6 +83,7 @@
 #define CTL_PARAM_OFFSET_PHY_Y1		18
 #define CTL_PARAM_OFFSET_PHY_W		22
 #define CTL_PARAM_OFFSET_PHY_H		24
+#define CTL_PARAM_OFFSET_FACTOR		32
 
 /* Communication commands */
 #define PACKET_SIZE			56
@@ -161,6 +162,7 @@ struct wdt87xx_sys_param {
 	u16	phy_ch_y;
 	u16	phy_w;
 	u16	phy_h;
+	u16	scaling_factor;
 	u32	max_x;
 	u32	max_y;
 };
@@ -401,7 +403,7 @@ static int wdt87xx_get_sysparam(struct i2c_client *client,
 	u8 buf[PKT_READ_SIZE];
 	int error;
 
-	error = wdt87xx_get_string(client, STRIDX_PARAMETERS, buf, 32);
+	error = wdt87xx_get_string(client, STRIDX_PARAMETERS, buf, 34);
 	if (error) {
 		dev_err(&client->dev, "failed to get parameters\n");
 		return error;
@@ -414,6 +416,10 @@ static int wdt87xx_get_sysparam(struct i2c_client *client,
 	param->phy_w = get_unaligned_le16(buf + CTL_PARAM_OFFSET_PHY_W) / 10;
 	param->phy_h = get_unaligned_le16(buf + CTL_PARAM_OFFSET_PHY_H) / 10;
 
+	/* Get the scaling factor of pixel to logical coordinate */
+	param->scaling_factor =
+			get_unaligned_le16(buf + CTL_PARAM_OFFSET_FACTOR);
+
 	param->max_x = MAX_UNIT_AXIS;
 	param->max_y = DIV_ROUND_CLOSEST(MAX_UNIT_AXIS * param->phy_h,
 					 param->phy_w);
@@ -905,8 +911,8 @@ static void wdt87xx_report_contact(struct input_dev *input,
 				   u8 *buf)
 {
 	int finger_id;
-	u32 x, y;
-	u8 w, p;
+	u32 x, y, w;
+	u8 p;
 
 	finger_id = (buf[FINGER_EV_V1_OFFSET_ID] >> 3) - 1;
 	if (finger_id < 0)
@@ -917,6 +923,8 @@ static void wdt87xx_report_contact(struct input_dev *input,
 		return;
 
 	w = buf[FINGER_EV_V1_OFFSET_W];
+	w *= param->scaling_factor;
+
 	p = buf[FINGER_EV_V1_OFFSET_P];
 
 	x = get_unaligned_le16(buf + FINGER_EV_V1_OFFSET_X);
@@ -995,7 +1003,8 @@ static int wdt87xx_ts_create_input_device(struct wdt87xx_data *wdt)
 	input_abs_set_res(input, ABS_MT_POSITION_X, res);
 	input_abs_set_res(input, ABS_MT_POSITION_Y, res);
 
-	input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0, 0xFF, 0, 0);
+	input_set_abs_params(input, ABS_MT_TOUCH_MAJOR,
+			     0, wdt->param.max_x, 0, 0);
 	input_set_abs_params(input, ABS_MT_PRESSURE, 0, 0xFF, 0, 0);
 
 	input_mt_init_slots(input, WDT_MAX_FINGER,