[PATCH v11 41/56] input: atmel_mxt_ts: export GPIO reset line via sysfs

Jiada Wang
2020-05-08T05:59:41Z

From: "George G. Davis" <george_davis@mentor.com>

N.B. Modifying the atmel_mxt_ts GPIO reset line during operation will
cause problems with normal driver operation. This feature is provided
as a diagnostic debug aid. It does not take into consideration any
pending operations which may be in progress. Modifying the atmel_mxt_ts
GPIO reset line at any time will inevitably cause the driver to fail.

Signed-off-by: George G. Davis <george_davis@mentor.com>
Signed-off-by: Rajeev Kumar <rajeev_kumar@mentor.com>
Signed-off-by: Jiada Wang <jiada_wang@mentor.com>
---
drivers/input/touchscreen/atmel_mxt_ts.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 75329f87927b..ceb14b4a8d4d 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -4080,6 +4080,19 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
return error;
}

+ if (data->reset_gpio) {
+ error = gpiod_export(data->reset_gpio, 0);
+ if (error)
+ return error;
+
+ error = gpiod_export_link(&client->dev, "reset",
+ data->reset_gpio);
+ if (error) {
+ gpiod_unexport(data->reset_gpio);
+ return error;
+ }
+ }
+
if (data->suspend_mode == MXT_SUSPEND_REGULATOR) {
enable_irq(data->irq);

@@ -4110,6 +4123,10 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
err_free_object:
mxt_free_input_device(data);
mxt_free_object_table(data);
+ if (data->reset_gpio) {
+ sysfs_remove_link(&client->dev.kobj, "reset");
+ gpiod_unexport(data->reset_gpio);
+ }
return error;
}

@@ -4119,6 +4136,10 @@ static int mxt_remove(struct i2c_client *client)

disable_irq(data->irq);
sysfs_remove_group(&client->dev.kobj, &mxt_fw_attr_group);
+ if (data->reset_gpio) {
+ sysfs_remove_link(&client->dev.kobj, "reset");
+ gpiod_unexport(data->reset_gpio);
+ }
mxt_debug_msg_remove(data);
mxt_sysfs_remove(data);
mxt_free_input_device(data);
--
2.17.1