Re: [PATCH 11/25] leds: lp8860: Use led_compose_name()

From: Jacek Anaszewski <jacek.anaszewski@gmail.com>
To: Dan Murphy <dmurphy@ti.com>, linux-leds@vger.kernel.org
Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	pavel@ucw.cz, robh@kernel.org
Subject: Re: [PATCH 11/25] leds: lp8860: Use led_compose_name()
Date: Mon, 11 Mar 2019 18:24:25 +0100	[thread overview]
Message-ID: <7242a6e9-ece7-22af-4d62-f2a6aa163579@gmail.com> (raw)
In-Reply-To: <cf42384b-cdbc-3ad7-468f-c4036579652f@ti.com>

Dan,

On 3/11/19 1:28 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.
>>
>> While at it, avoid iterating through available child of nodes
>> in favor of obtaining single expected child node using single
>> call to of_get_next_available_child().
>>
>> Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
>> Cc: Dan Murphy <dmurphy@ti.com>
>> ---
>>   drivers/leds/leds-lp8860.c | 38 +++++++++++++++++++-------------------
>>   1 file changed, 19 insertions(+), 19 deletions(-)
>>
>> diff --git a/drivers/leds/leds-lp8860.c b/drivers/leds/leds-lp8860.c
>> index 39c72a908f3b..7c12ccdc1f2f 100644
>> --- a/drivers/leds/leds-lp8860.c
>> +++ b/drivers/leds/leds-lp8860.c
>> @@ -22,7 +22,6 @@
>>   #include <linux/of_gpio.h>
>>   #include <linux/gpio/consumer.h>
>>   #include <linux/slab.h>
>> -#include <uapi/linux/uleds.h>
>>   
>>   #define LP8860_DISP_CL1_BRT_MSB		0x00
>>   #define LP8860_DISP_CL1_BRT_LSB		0x01
>> @@ -87,6 +86,8 @@
>>   
>>   #define LP8860_CLEAR_FAULTS		0x01
>>   
>> +#define LP8860_NAME			"lp8860"
>> +
>>   /**
>>    * struct lp8860_led -
>>    * @lock - Lock for reading/writing the device
>> @@ -96,7 +97,6 @@
>>    * @eeprom_regmap - EEPROM register map
>>    * @enable_gpio - VDDIO/EN gpio to enable communication interface
>>    * @regulator - LED supply regulator pointer
>> - * @label - LED label
>>    */
>>   struct lp8860_led {
>>   	struct mutex lock;
>> @@ -106,7 +106,6 @@ struct lp8860_led {
>>   	struct regmap *eeprom_regmap;
>>   	struct gpio_desc *enable_gpio;
>>   	struct regulator *regulator;
>> -	char label[LED_MAX_NAME_SIZE];
>>   };
>>   
>>   struct lp8860_eeprom_reg {
>> @@ -387,25 +386,26 @@ static int lp8860_probe(struct i2c_client *client,
>>   	struct lp8860_led *led;
>>   	struct device_node *np = client->dev.of_node;
>>   	struct device_node *child_node;
>> -	const char *name;
>> +	struct led_init_data init_data;
>>   
>>   	led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
>>   	if (!led)
>>   		return -ENOMEM;
>>   
>> -	for_each_available_child_of_node(np, child_node) {
>> -		led->led_dev.default_trigger = of_get_property(child_node,
>> -						    "linux,default-trigger",
>> -						    NULL);
>> -
>> -		ret = of_property_read_string(child_node, "label", &name);
>> -		if (!ret)
>> -			snprintf(led->label, sizeof(led->label), "%s:%s",
>> -				 id->name, name);
>> -		else
>> -			snprintf(led->label, sizeof(led->label),
>> -				"%s::display_cluster", id->name);
>> -	}
>> +	child_node = of_get_next_available_child(np, NULL);
> 
> Again this device has multiple outputs that can be banked or separated.
> 
> I would prefer to leave the iteration and just change the name generation.

In [0] you agreed on removing that. This code is simply broken since
there is only one instance of struct lp8860_led allocated.

>> +	if (!child_node)
>> +		return -EINVAL;
>> +
>> +	init_data.fwnode = of_fwnode_handle(child_node),
>> +
>> +	led->led_dev.default_trigger = of_get_property(child_node,
>> +					    "linux,default-trigger",
>> +					    NULL);
>> +
>> +	ret = led_compose_name(init_data.fwnode, LP8860_NAME,
>> +			       ":display_cluster", init_data.name);
>> +	if (ret)
>> +		return ret;
>>   
>>   	led->enable_gpio = devm_gpiod_get_optional(&client->dev,
>>   						   "enable", GPIOD_OUT_LOW);
>> @@ -420,7 +420,6 @@ static int lp8860_probe(struct i2c_client *client,
>>   		led->regulator = NULL;
>>   
>>   	led->client = client;
>> -	led->led_dev.name = led->label;
>>   	led->led_dev.brightness_set_blocking = lp8860_brightness_set;
>>   
>>   	mutex_init(&led->lock);
>> @@ -447,7 +446,8 @@ static int lp8860_probe(struct i2c_client *client,
>>   	if (ret)
>>   		return ret;
>>   
>> -	ret = devm_led_classdev_register(&client->dev, &led->led_dev);
>> +	ret = devm_led_classdev_register_ext(&client->dev, &led->led_dev,
>> +					     &init_data);
>>   	if (ret) {
>>   		dev_err(&client->dev, "led register err: %d\n", ret);
>>   		return ret;
>>
> 
> 

[0] https://lkml.org/lkml/2018/11/12/2231

-- 
Best regards,
Jacek Anaszewski