[PATCH] input: goodix: Add option to power off the controller during suspend

[Jan Jasper de Kroon <jajadekroon@gmail.com>]

From: Ondřej Jirman <megi@xff.cz>

For whatever reason the controller is not suspended on Pinephone
by the default procedure. It consumes quite a bit of power (~40mW)
during system sleep, and more when the screen is touched.

Let's power off the controller during system sleep instead.

Signed-off-by: Ondrej Jirman <megi@xff.cz>

input: goodix: Don't disable regulators during suspend

It does no harm to disable them, but on Pinephone we have other
peripherals attached to the same power supplies, whose drivers
will not reference the regulator, so powering down the regulators
from Goodix driver will break those other devices.

Until those drivers gain the regulator support, don't disable
the regulators in Goodix driver.

Signed-off-by: Ondrej Jirman <megi@xff.cz>
Signed-off-by: Jan Jasper de Kroon <jajadekroon@gmail.com>
---
 drivers/input/touchscreen/goodix.c | 23 +++++++++++++++++++++++
 drivers/input/touchscreen/goodix.h |  1 +
 2 files changed, 24 insertions(+)

diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
index b348172f19c3..e6d054ede960 100644
--- a/drivers/input/touchscreen/goodix.c
+++ b/drivers/input/touchscreen/goodix.c
@@ -1284,6 +1284,7 @@ static void goodix_disable_regulators(void *arg)
 
 static int goodix_ts_probe(struct i2c_client *client)
 {
+	struct device_node *np = client->dev.of_node;
 	struct goodix_ts_data *ts;
 	const char *cfg_name;
 	int error;
@@ -1303,6 +1304,7 @@ static int goodix_ts_probe(struct i2c_client *client)
 	i2c_set_clientdata(client, ts);
 	init_completion(&ts->firmware_loading_complete);
 	ts->contact_size = GOODIX_CONTACT_SIZE;
+	ts->poweroff_in_suspend = of_property_read_bool(np, "poweroff-in-suspend");
 
 	error = goodix_get_gpio_config(ts);
 	if (error)
@@ -1410,6 +1412,13 @@ static int goodix_suspend(struct device *dev)
 	if (ts->load_cfg_from_disk)
 		wait_for_completion(&ts->firmware_loading_complete);
 
+	if (ts->poweroff_in_suspend) {
+		goodix_free_irq(ts);
+		goodix_irq_direction_output(ts, 0);
+		gpiod_direction_output(ts->gpiod_rst, 0);
+		return 0;
+	}
+
 	/* We need gpio pins to suspend/resume */
 	if (ts->irq_pin_access_method == IRQ_PIN_ACCESS_NONE) {
 		disable_irq(client->irq);
@@ -1455,6 +1464,20 @@ static int goodix_resume(struct device *dev)
 	u8 config_ver;
 	int error;
 
+	if (ts->poweroff_in_suspend) {
+		error = goodix_reset(ts);
+		if (error) {
+			dev_err(dev, "Controller reset failed.\n");
+			return error;
+		}
+
+		error = goodix_request_irq(ts);
+		if (error)
+			return error;
+
+		return 0;
+	}
+
 	if (ts->irq_pin_access_method == IRQ_PIN_ACCESS_NONE) {
 		enable_irq(client->irq);
 		return 0;
diff --git a/drivers/input/touchscreen/goodix.h b/drivers/input/touchscreen/goodix.h
index 87797cc88b32..dc358bcda698 100644
--- a/drivers/input/touchscreen/goodix.h
+++ b/drivers/input/touchscreen/goodix.h
@@ -104,6 +104,7 @@ struct goodix_ts_data {
 	u8 main_clk[GOODIX_MAIN_CLK_LEN];
 	int bak_ref_len;
 	u8 *bak_ref;
+	bool poweroff_in_suspend;
 };
 
 int goodix_i2c_read(struct i2c_client *client, u16 reg, u8 *buf, int len);
-- 
2.34.3