Re: [PATCH 13/25] leds: lm3692x: Use led_compose_name()

[Jacek Anaszewski]

Dan,

On 3/11/19 1:38 PM, Dan Murphy wrote:
> On 3/10/19 1:28 PM, Jacek Anaszewski wrote:
> > Switch to using generic LED support for composing LED class
> > device name.
> >
> > Since the same device strings would be used in two places,
> > then add macros LM36922_NAME and LM36922_NAME for use in
> > lm3692x_probe_dt(() and lm3692x_id array.
> >
> > Signed-off-by: Jacek Anaszewski <jacek.anaszewski@xxxxxxxxx>
> > Acked-by: Pavel Machek <pavel@xxxxxx>
> > Cc: Dan Murphy <dmurphy@xxxxxx>
> > ---
> >   drivers/leds/leds-lm3692x.c | 39 ++++++++++++++++++++-------------------
> >   1 file changed, 20 insertions(+), 19 deletions(-)
> >
> > diff --git a/drivers/leds/leds-lm3692x.c b/drivers/leds/leds-lm3692x.c
> > index 4f413a7c5f05..9dfc0f28a9c8 100644
> > --- a/drivers/leds/leds-lm3692x.c
> > +++ b/drivers/leds/leds-lm3692x.c
> > @@ -13,7 +13,6 @@
> >   #include <linux/regmap.h>
> >   #include <linux/regulator/consumer.h>
> >   #include <linux/slab.h>
> > -#include <uapi/linux/uleds.h>
> >   
> >   #define LM36922_MODEL	0
> >   #define LM36923_MODEL	1
> > @@ -95,6 +94,9 @@
> >   #define LM3692X_FAULT_FLAG_SHRT BIT(3)
> >   #define LM3692X_FAULT_FLAG_OPEN BIT(4)
> >   
> > +#define LM36922_NAME "lm36922"
> > +#define LM36923_NAME "lm36923"
> > +
> >   /**
> >    * struct lm3692x_led -
> >    * @lock - Lock for reading/writing the device
> > @@ -103,7 +105,6 @@
> >    * @regmap - Devices register map
> >    * @enable_gpio - VDDIO/EN gpio to enable communication interface
> >    * @regulator - LED supply regulator pointer
> > - * @label - LED label
> >    * @led_enable - LED sync to be enabled
> >    * @model_id - Current device model ID enumerated
> >    */
> > @@ -114,7 +115,6 @@ struct lm3692x_led {
> >   	struct regmap *regmap;
> >   	struct gpio_desc *enable_gpio;
> >   	struct regulator *regulator;
> > -	char label[LED_MAX_NAME_SIZE];
> >   	int led_enable;
> >   	int model_id;
> >   };
> > @@ -325,7 +325,8 @@ static int lm3692x_init(struct lm3692x_led *led)
> >   static int lm3692x_probe_dt(struct lm3692x_led *led)
> >   {
> >   	struct fwnode_handle *child = NULL;
> > -	const char *name;
> > +	struct led_init_data init_data;
> > +	char *model_name;
> >   	int ret;
> >   
> >   	led->enable_gpio = devm_gpiod_get_optional(&led->client->dev,
> > @@ -346,17 +347,20 @@ static int lm3692x_probe_dt(struct lm3692x_led *led)
> >   		dev_err(&led->client->dev, "No LED Child node\n");
> >   		return -ENODEV;
> >   	}
> > +	init_data.fwnode = child;
> >   
> > -	fwnode_property_read_string(child, "linux,default-trigger",
> > -				    &led->led_dev.default_trigger);
> > +	if (led->model_id == LM36922_MODEL)
> > +		model_name =  LM36922_NAME;
> > +	else
> > +		model_name =  LM36923_NAME;
> >   
>
>
> Why do we need this change?
>
> led->client->name should suffice here and then we do not have to #define the name at all.

Indeed, at that time I was not aware that I2C subsystem creates client
name using product name from DT compatible property.

> > -	ret = fwnode_property_read_string(child, "label", &name);
> > +	ret = led_compose_name(child, model_name, ":backlight_cluster",
> > +			       init_data.name);
> >   	if (ret)
> > -		snprintf(led->label, sizeof(led->label),
> > -			"%s::", led->client->name);
> > -	else
> > -		snprintf(led->label, sizeof(led->label),
> > -			 "%s:%s", led->client->name, name);
> > +		return ret;
> > +
> > +	fwnode_property_read_string(child, "linux,default-trigger",
> > +				    &led->led_dev.default_trigger);
> >   
> >   	ret = fwnode_property_read_u32(child, "reg", &led->led_enable);
> >   	if (ret) {
> > @@ -364,16 +368,13 @@ static int lm3692x_probe_dt(struct lm3692x_led *led)
> >   		return ret;
> >   	}
> >   
> > -	led->led_dev.name = led->label;
> > -
> > -	ret = devm_led_classdev_register(&led->client->dev, &led->led_dev);
> > +	ret = devm_led_classdev_register_ext(&led->client->dev, &led->led_dev,
> > +					     &init_data);
> >   	if (ret) {
> >   		dev_err(&led->client->dev, "led register err: %d\n", ret);
> >   		return ret;
> >   	}
> >   
> > -	led->led_dev.dev->of_node = to_of_node(child);
> > -
>
> Seems like an additional change here not documented.
> If it is a bug fix or an enhancement probably need a separate patch.
>
> I do know why this is removed just need tracability on the log.

OK, I will add the comment.

> >   	return 0;
> >   }
> >   
> > @@ -439,8 +440,8 @@ static int lm3692x_remove(struct i2c_client *client)
> >   }
> >   
> >   static const struct i2c_device_id lm3692x_id[] = {
> > -	{ "lm36922", LM36922_MODEL },
> > -	{ "lm36923", LM36923_MODEL },
> > +	{ LM36922_NAME, LM36922_MODEL },
> > +	{ LM36923_NAME, LM36923_MODEL },
> >   	{ }
> >   };
> >   MODULE_DEVICE_TABLE(i2c, lm3692x_id);

--
Best regards,
Jacek Anaszewski