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

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

[Grant Feng]

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@163.com>
---
 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,
 					  IS31FL319X_AUDIO_GAIN_DB_MAX);
 
+	is31->sdb_pin = gpiod_get(dev, "sdb", GPIOD_ASIS);
+	if (IS_ERR(is31->sdb_pin)) {
+		dev_warn(dev, "failed to get gpio_sdb, try default\r\n");
+	} else {
+		gpiod_direction_output(is31->sdb_pin, 0);
+		mdelay(5);
+		gpiod_direction_output(is31->sdb_pin, 1);
+	}
+
 	return 0;
 
 put_child_node:
-- 
2.17.1

[PATCH 2/2] DT: leds: Add an optional property named 'sdb-gpios'

[Grant Feng]

The chip enters hardware shutdown when the SDB pin is pulled low.
The chip releases hardware shutdown when the SDB pin is pulled high.

Signed-off-by: Grant Feng <von81@163.com>
---
 Documentation/devicetree/bindings/leds/leds-is31fl319x.txt | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/leds/leds-is31fl319x.txt b/Documentation/devicetree/bindings/leds/leds-is31fl319x.txt
index fc2603484544..e8bef4be57dc 100644
--- a/Documentation/devicetree/bindings/leds/leds-is31fl319x.txt
+++ b/Documentation/devicetree/bindings/leds/leds-is31fl319x.txt
@@ -16,6 +16,7 @@ Optional properties:
 - audio-gain-db : audio gain selection for external analog modulation input.
 	Valid values: 0 - 21, step by 3 (rounded down)
 	Default: 0
+- sdb-gpios : Specifier of the GPIO connected to SDB pin.
 
 Each led is represented as a sub-node of the issi,is31fl319x device.
 There can be less leds subnodes than the chip can support but not more.
@@ -44,6 +45,7 @@ fancy_leds: leds@65 {
 	#address-cells = <1>;
 	#size-cells = <0>;
 	reg = <0x65>;
+	sdb-gpios = <&gpio0 11 GPIO_ACTIVE_HIGH>;
 
 	red_aux: led@1 {
 		label = "red:aux";
-- 
2.17.1

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

[Dan Murphy]

Grant

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@163.com>
> ---
>   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,
>   					  IS31FL319X_AUDIO_GAIN_DB_MAX);
>   
> +	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.

Dan

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

[Dan Murphy]

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

[Pavel Machek]

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Hi!
> 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@163.com>
> > ---
> >   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,
> >   					  IS31FL319X_AUDIO_GAIN_DB_MAX);
> > +	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.

Yep, thanks for the review, I dropped it from for-next.

And yes, this should be in series with device tree change, and we need
Rob 's ack.

Best regards,
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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

[Grant Feng]

Thanks for the review, I will rewrit it.

Grant

On 2020-08-06 23:00, Dan Murphy wrote:
> Grant
>
> 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@163.com>
>> ---
>>   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,
>>                         IS31FL319X_AUDIO_GAIN_DB_MAX);
>>   +    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.
>
> Dan
>