[PATCH 4.19 07/33] Input: silead - Always support 10 fingers

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

4.19-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Hans de Goede <hdegoede@redhat.com>

[ Upstream commit 38a38f5a36da9820680d413972cb733349400532 ]

When support for Silead touchscreens was orginal added some touchscreens
with older firmware versions only supported 5 fingers and this was made
the default requiring the setting of a "silead,max-fingers=10" uint32
device-property for all touchscreen models which do support 10 fingers.

There are very few models with the old 5 finger fw, so in practice the
setting of the "silead,max-fingers=10" is boilerplate which needs to
be copy and pasted to every touchscreen config.

Reporting that 10 fingers are supported on devices which only support
5 fingers doesn't cause any problems for userspace in practice, since
at max 4 finger gestures are supported anyways. Drop the max_fingers
configuration and simply always assume 10 fingers.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Link: https://lore.kernel.org/r/20240525193854.39130-2-hdegoede@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/input/touchscreen/silead.c | 19 +++++--------------
 1 file changed, 5 insertions(+), 14 deletions(-)

diff --git a/drivers/input/touchscreen/silead.c b/drivers/input/touchscreen/silead.c
index a787a6aefc69f..78f08ca3f8442 100644
--- a/drivers/input/touchscreen/silead.c
+++ b/drivers/input/touchscreen/silead.c
@@ -78,7 +78,6 @@ struct silead_ts_data {
 	struct regulator_bulk_data regulators[2];
 	char fw_name[64];
 	struct touchscreen_properties prop;
-	u32 max_fingers;
 	u32 chip_id;
 	struct input_mt_pos pos[SILEAD_MAX_FINGERS];
 	int slots[SILEAD_MAX_FINGERS];
@@ -106,7 +105,7 @@ static int silead_ts_request_input_dev(struct silead_ts_data *data)
 	input_set_abs_params(data->input, ABS_MT_POSITION_Y, 0, 4095, 0, 0);
 	touchscreen_parse_properties(data->input, true, &data->prop);
 
-	input_mt_init_slots(data->input, data->max_fingers,
+	input_mt_init_slots(data->input, SILEAD_MAX_FINGERS,
 			    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED |
 			    INPUT_MT_TRACK);
 
@@ -153,10 +152,10 @@ static void silead_ts_read_data(struct i2c_client *client)
 		return;
 	}
 
-	if (buf[0] > data->max_fingers) {
+	if (buf[0] > SILEAD_MAX_FINGERS) {
 		dev_warn(dev, "More touches reported then supported %d > %d\n",
-			 buf[0], data->max_fingers);
-		buf[0] = data->max_fingers;
+			 buf[0], SILEAD_MAX_FINGERS);
+		buf[0] = SILEAD_MAX_FINGERS;
 	}
 
 	touch_nr = 0;
@@ -208,7 +207,6 @@ static void silead_ts_read_data(struct i2c_client *client)
 
 static int silead_ts_init(struct i2c_client *client)
 {
-	struct silead_ts_data *data = i2c_get_clientdata(client);
 	int error;
 
 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
@@ -218,7 +216,7 @@ static int silead_ts_init(struct i2c_client *client)
 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
 
 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_TOUCH_NR,
-					data->max_fingers);
+					  SILEAD_MAX_FINGERS);
 	if (error)
 		goto i2c_write_err;
 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
@@ -445,13 +443,6 @@ static void silead_ts_read_props(struct i2c_client *client)
 	const char *str;
 	int error;
 
-	error = device_property_read_u32(dev, "silead,max-fingers",
-					 &data->max_fingers);
-	if (error) {
-		dev_dbg(dev, "Max fingers read error %d\n", error);
-		data->max_fingers = 5; /* Most devices handle up-to 5 fingers */
-	}
-
 	error = device_property_read_string(dev, "firmware-name", &str);
 	if (!error)
 		snprintf(data->fw_name, sizeof(data->fw_name),
-- 
2.43.0