[PATCH v7 2/4] Input: goodix - Add regulators suppot

From: Jagan Teki
Date: Thu Mar 21 2019 - 04:21:26 EST


Goodix CTP controllers require AVDD28, VDDIO regulators for power-on
sequence.

The delay between these regualtor operations as per Power-on Timing
from datasheet[1] is 0 (T1 >= 0 usec).

So, enable and disable these regulators in proper order using normal
regulator functions without any delay in between.

[1] GT5663 Datasheet_English_20151106_Rev.01

Signed-off-by: Jagan Teki <jagan@xxxxxxxxxxxxxxxxxxxx>
---
drivers/input/touchscreen/goodix.c | 58 ++++++++++++++++++++++++++++++
1 file changed, 58 insertions(+)

diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
index f57d82220a88..de5b80a08f41 100644
--- a/drivers/input/touchscreen/goodix.c
+++ b/drivers/input/touchscreen/goodix.c
@@ -27,6 +27,7 @@
#include <linux/delay.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
+#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#include <linux/acpi.h>
#include <linux/of.h>
@@ -47,6 +48,8 @@ struct goodix_ts_data {
struct touchscreen_properties prop;
unsigned int max_touch_num;
unsigned int int_trigger_type;
+ struct regulator *avdd28;
+ struct regulator *vddio;
struct gpio_desc *gpiod_int;
struct gpio_desc *gpiod_rst;
u16 id;
@@ -532,6 +535,24 @@ static int goodix_get_gpio_config(struct goodix_ts_data *ts)
return -EINVAL;
dev = &ts->client->dev;

+ ts->avdd28 = devm_regulator_get(dev, "AVDD28");
+ if (IS_ERR(ts->avdd28)) {
+ error = PTR_ERR(ts->avdd28);
+ if (error != -EPROBE_DEFER)
+ dev_err(dev,
+ "Failed to get AVDD28 regulator: %d\n", error);
+ return error;
+ }
+
+ ts->vddio = devm_regulator_get(dev, "VDDIO");
+ if (IS_ERR(ts->vddio)) {
+ error = PTR_ERR(ts->vddio);
+ if (error != -EPROBE_DEFER)
+ dev_err(dev,
+ "Failed to get VDDIO regulator: %d\n", error);
+ return error;
+ }
+
/* Get the interrupt GPIO pin number */
gpiod = devm_gpiod_get_optional(dev, GOODIX_GPIO_INT_NAME, GPIOD_IN);
if (IS_ERR(gpiod)) {
@@ -764,6 +785,17 @@ static void goodix_config_cb(const struct firmware *cfg, void *ctx)
complete_all(&ts->firmware_loading_complete);
}

+static void goodix_disable_regulator(void *arg)
+{
+ struct goodix_ts_data *ts = arg;
+
+ if (!IS_ERR(ts->vddio))
+ regulator_disable(ts->vddio);
+
+ if (!IS_ERR(ts->avdd28))
+ regulator_disable(ts->avdd28);
+}
+
static int goodix_ts_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
@@ -789,6 +821,32 @@ static int goodix_ts_probe(struct i2c_client *client,
if (error)
return error;

+ error = devm_add_action_or_reset(&client->dev,
+ goodix_disable_regulator, ts);
+ if (error)
+ return error;
+
+ /* power the controller */
+ if (!IS_ERR(ts->avdd28)) {
+ error = regulator_enable(ts->avdd28);
+ if (error) {
+ dev_err(&client->dev,
+ "Failed to enable AVDD28 regulator: %d\n",
+ error);
+ return error;
+ }
+ }
+
+ if (!IS_ERR(ts->vddio)) {
+ error = regulator_enable(ts->vddio);
+ if (error) {
+ dev_err(&client->dev,
+ "Failed to enable VDDIO regulator: %d\n",
+ error);
+ return error;
+ }
+ }
+
if (ts->gpiod_int && ts->gpiod_rst) {
/* reset the controller */
error = goodix_reset(ts);
--
2.18.0.321.gffc6fa0e3