Re: [PATCH 1/2] leds: is31fl319x: Add sdb pin and generate a 5ms low pulse when startup

From: Dan Murphy
Date: Thu Aug 06 2020 - 12:53:26 EST


On 8/6/20 1:21 AM, Grant Feng wrote:
generate a 5ms low pulse on sdb pin when startup, then the chip
becomes more stable in the complex EM environment.

Signed-off-by: Grant Feng <von81@xxxxxxx>
drivers/leds/leds-is31fl319x.c | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/drivers/leds/leds-is31fl319x.c b/drivers/leds/leds-is31fl319x.c
index ca6634b8683c..b4f70002cec9 100644
--- a/drivers/leds/leds-is31fl319x.c
+++ b/drivers/leds/leds-is31fl319x.c
@@ -16,6 +16,8 @@
#include <linux/of_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
/* register numbers */
#define IS31FL319X_SHUTDOWN 0x00
@@ -61,6 +63,7 @@
struct is31fl319x_chip {
const struct is31fl319x_chipdef *cdef;
struct i2c_client *client;
+ struct gpio_desc *sdb_pin;
struct regmap *regmap;
struct mutex lock;
u32 audio_gain_db;
@@ -265,6 +268,15 @@ static int is31fl319x_parse_dt(struct device *dev,
is31->audio_gain_db = min(is31->audio_gain_db,
+ is31->sdb_pin = gpiod_get(dev, "sdb", GPIOD_ASIS);

Since this is optional maybe use devm_gpiod_get_optional.

If this is required for stability then if the GPIO is not present then the parse_dt should return the error.

And use the devm_gpiod_get call.  Otherwise you are missing the gpiod_put when exiting or removing the driver.