[PATCH 1/4] Input: goodix - Try resetting the controller when no config is set

[Hans de Goede <hdegoede@redhat.com>]

On ACPI systems (irq_pin_access_method == IRQ_PIN_ACCESS_ACPI_*) the driver
does not reset the controller at probe time, because sometimes the system
firmware loads a config and resetting might loose this config.

On the Nanote UMPC-01 device OTOH the config is in flash of the controller,
the controller needs a reset to load this; and the system firmware does not
reset the controller on a cold boot.

To fix the Nanote UMPC-01 touchscreen not working on a cold boot, try
resetting the controller and then re-reading the config when encountering
a config with 0 width/height/max_touch_num value and the controller has
not already been reset by goodix_ts_probe().

This should be safe to do in general because normally we should never
encounter a config with 0 width/height/max_touch_num. Doing this in
general not only avoids the need for a DMI quirk, but also might help
other systems.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/input/touchscreen/goodix.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
index a33cc7950cf5..c281e49826c2 100644
--- a/drivers/input/touchscreen/goodix.c
+++ b/drivers/input/touchscreen/goodix.c
@@ -1158,6 +1158,7 @@ static int goodix_configure_dev(struct goodix_ts_data *ts)
 	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);
 
+retry_read_config:
 	/* Read configuration and apply touchscreen parameters */
 	goodix_read_config(ts);
 
@@ -1165,6 +1166,16 @@ static int goodix_configure_dev(struct goodix_ts_data *ts)
 	touchscreen_parse_properties(ts->input_dev, true, &ts->prop);
 
 	if (!ts->prop.max_x || !ts->prop.max_y || !ts->max_touch_num) {
+		if (!ts->reset_controller_at_probe &&
+		    ts->irq_pin_access_method != IRQ_PIN_ACCESS_NONE) {
+			dev_info(&ts->client->dev, "Config not set, resetting controller\n");
+			/* Retry after a controller reset */
+			ts->reset_controller_at_probe = true;
+			error = goodix_reset(ts);
+			if (error)
+				return error;
+			goto retry_read_config;
+		}
 		dev_err(&ts->client->dev,
 			"Invalid config (%d, %d, %d), using defaults\n",
 			ts->prop.max_x, ts->prop.max_y, ts->max_touch_num);
-- 
2.37.3