Re: [PATCH] gpiolib: provide and use gpiod_line_state_notify()

[Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>]

On Mon, Aug 21, 2023 at 04:18:27PM +0200, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
> 
> Wrap the calls to blocking_notifier_call_chain() for the line state
> notifier with a helper that allows us to use fewer lines of code and
> simpler syntax.

This change I like, no questions asked.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
> ---
>  drivers/gpio/gpiolib-cdev.c | 17 +++++------------
>  drivers/gpio/gpiolib.c      | 12 ++++++++----
>  drivers/gpio/gpiolib.h      |  1 +
>  3 files changed, 14 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c
> index 35dcaf78aed6..e39d344feb28 100644
> --- a/drivers/gpio/gpiolib-cdev.c
> +++ b/drivers/gpio/gpiolib-cdev.c
> @@ -230,9 +230,7 @@ static long linehandle_set_config(struct linehandle_state *lh,
>  				return ret;
>  		}
>  
> -		blocking_notifier_call_chain(&desc->gdev->line_state_notifier,
> -					     GPIO_V2_LINE_CHANGED_CONFIG,
> -					     desc);
> +		gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG);
>  	}
>  	return 0;
>  }
> @@ -414,8 +412,7 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip)
>  				goto out_free_lh;
>  		}
>  
> -		blocking_notifier_call_chain(&desc->gdev->line_state_notifier,
> -					     GPIO_V2_LINE_CHANGED_REQUESTED, desc);
> +		gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_REQUESTED);
>  
>  		dev_dbg(&gdev->dev, "registered chardev handle for line %d\n",
>  			offset);
> @@ -1420,9 +1417,7 @@ static long linereq_set_config_unlocked(struct linereq *lr,
>  
>  		WRITE_ONCE(line->edflags, edflags);
>  
> -		blocking_notifier_call_chain(&desc->gdev->line_state_notifier,
> -					     GPIO_V2_LINE_CHANGED_CONFIG,
> -					     desc);
> +		gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG);
>  	}
>  	return 0;
>  }
> @@ -1737,8 +1732,7 @@ static int linereq_create(struct gpio_device *gdev, void __user *ip)
>  
>  		lr->lines[i].edflags = edflags;
>  
> -		blocking_notifier_call_chain(&desc->gdev->line_state_notifier,
> -					     GPIO_V2_LINE_CHANGED_REQUESTED, desc);
> +		gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_REQUESTED);
>  
>  		dev_dbg(&gdev->dev, "registered chardev handle for line %d\n",
>  			offset);
> @@ -2156,8 +2150,7 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
>  	if (ret)
>  		goto out_free_le;
>  
> -	blocking_notifier_call_chain(&desc->gdev->line_state_notifier,
> -				     GPIO_V2_LINE_CHANGED_REQUESTED, desc);
> +	gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_REQUESTED);
>  
>  	irq = gpiod_to_irq(desc);
>  	if (irq <= 0) {
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index 0737952882cd..43162fd71d92 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -2160,8 +2160,7 @@ static bool gpiod_free_commit(struct gpio_desc *desc)
>  	}
>  
>  	spin_unlock_irqrestore(&gpio_lock, flags);
> -	blocking_notifier_call_chain(&desc->gdev->line_state_notifier,
> -				     GPIOLINE_CHANGED_RELEASED, desc);
> +	gpiod_line_state_notify(desc, GPIOLINE_CHANGED_RELEASED);
>  
>  	return ret;
>  }
> @@ -3729,6 +3728,12 @@ int gpiod_set_array_value_cansleep(unsigned int array_size,
>  }
>  EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);
>  
> +void gpiod_line_state_notify(struct gpio_desc *desc, unsigned long action)
> +{
> +	blocking_notifier_call_chain(&desc->gdev->line_state_notifier,
> +				     action, desc);

action can be on previous line, but this is the logical split, so fine as is.

> +}
> +
>  /**
>   * gpiod_add_lookup_table() - register GPIO device consumers
>   * @table: table of consumers to register
> @@ -3996,8 +4001,7 @@ static struct gpio_desc *gpiod_find_and_request(struct device *consumer,
>  		return ERR_PTR(ret);
>  	}
>  
> -	blocking_notifier_call_chain(&desc->gdev->line_state_notifier,
> -				     GPIOLINE_CHANGED_REQUESTED, desc);
> +	gpiod_line_state_notify(desc, GPIOLINE_CHANGED_REQUESTED);
>  
>  	return desc;
>  }
> diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h
> index 54012605b4a4..0d81ac3bbb40 100644
> --- a/drivers/gpio/gpiolib.h
> +++ b/drivers/gpio/gpiolib.h
> @@ -146,6 +146,7 @@ int gpiod_set_array_value_complex(bool raw, bool can_sleep,
>  extern spinlock_t gpio_lock;
>  extern struct list_head gpio_devices;
>  
> +void gpiod_line_state_notify(struct gpio_desc *desc, unsigned long action);
>  
>  /**
>   * struct gpio_desc - Opaque descriptor for a GPIO
> -- 
> 2.39.2
> 

-- 
With Best Regards,
Andy Shevchenko