[PATCH v3] Input: elants_i2c - Report resolution of ABS_MT_TOUCH_MAJOR by FW information.

[Johnny Chuang <johnny.chuang.emc@gmail.com>]

This patch adds a new behavior to report touch major resolution
based on information provided by firmware.

In initial process, driver acquires touch information from touch ic.
It contains one byte about the resolution value of ABS_MT_TOUCH_MAJOR.
Touch driver will report touch major resolution by this information.

Signed-off-by: Johnny Chuang <johnny.chuang.emc@gmail.com>
---
Changes in v2:
  - register a real resolution value from firmware,
	instead of hardcoding resolution value as 1 by flag.
Changes in v3:
  - modify git log message from flag to real value.
  - modify driver comment from flag to real value.
---
 drivers/input/touchscreen/elants_i2c.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/input/touchscreen/elants_i2c.c b/drivers/input/touchscreen/elants_i2c.c
index b0bd5bb..661a3ee 100644
--- a/drivers/input/touchscreen/elants_i2c.c
+++ b/drivers/input/touchscreen/elants_i2c.c
@@ -151,6 +151,7 @@ struct elants_data {
 
 	bool wake_irq_enabled;
 	bool keep_power_in_suspend;
+	u8 report_major_resolution;
 
 	/* Must be last to be used for DMA operations */
 	u8 buf[MAX_PACKET_SIZE] ____cacheline_aligned;
@@ -459,6 +460,9 @@ static int elants_i2c_query_ts_info(struct elants_data *ts)
 	rows = resp[2] + resp[6] + resp[10];
 	cols = resp[3] + resp[7] + resp[11];
 
+	/* get report resolution value of ABS_MT_TOUCH_MAJOR */
+	ts->report_major_resolution = resp[16];
+
 	/* Process mm_to_pixel information */
 	error = elants_i2c_execute_command(client,
 					   get_osr_cmd, sizeof(get_osr_cmd),
@@ -1325,6 +1329,8 @@ static int elants_i2c_probe(struct i2c_client *client,
 			     0, MT_TOOL_PALM, 0, 0);
 	input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->x_res);
 	input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->y_res);
+	if (ts->report_major_resolution > 0)
+		input_abs_set_res(ts->input, ABS_MT_TOUCH_MAJOR, ts->report_major_resolution);
 
 	touchscreen_parse_properties(ts->input, true, &ts->prop);
 
-- 
2.7.4