Re: [PATCH -next 1/2] leds: add /sys/devices/virtual/led-trigger/

[Greg Kroah-Hartman]

On Thu, Oct 03, 2019 at 12:13:00AM +0900, Akinobu Mita wrote:
> Reading /sys/class/leds/<led>/trigger returns all available LED triggers.
> However, this violates the "one value per file" rule of sysfs.
> 
> This makes led_triggers "real" devices and provides an
> /sys/devices/virtual/led-trigger/ directory that contains a sub-directoriy
> for each LED trigger device. The name of the sub-directory matches the LED
> trigger name.
> 
> We can find all available LED triggers by listing this directory contents.
> 
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
> Cc: Jacek Anaszewski <jacek.anaszewski@xxxxxxxxx>
> Cc: Pavel Machek <pavel@xxxxxx>
> Cc: Dan Murphy <dmurphy@xxxxxx>
> Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx>
> ---
>  .../ABI/testing/sysfs-devices-virtual-led-trigger  |  8 +++
>  drivers/leds/led-triggers.c                        | 57 ++++++++++++++++++++++
>  include/linux/leds.h                               |  3 ++
>  3 files changed, 68 insertions(+)
>  create mode 100644 Documentation/ABI/testing/sysfs-devices-virtual-led-trigger
> 
> diff --git a/Documentation/ABI/testing/sysfs-devices-virtual-led-trigger b/Documentation/ABI/testing/sysfs-devices-virtual-led-trigger
> new file mode 100644
> index 0000000..b8eb8f3
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-devices-virtual-led-trigger
> @@ -0,0 +1,8 @@
> +What:		/sys/devices/virtual/leds-trigger/
> +Date:		September 2019
> +KernelVersion:	5.5
> +Contact:	linux-leds@xxxxxxxxxxxxxxx
> +Description:
> +		This directory contains a sub-directoriy for each LED trigger

"directoriy"?

> +		device. The name of the sub-directory matches the LED trigger
> +		name.

You are just creating directories here, and doing nothing with them,
why?  That seems kind of pointless.

thanks,

greg k-h