Re: [PATCH v3 bus+gpio 3/5] bus: moxtet: Add sysfs documentation

[Linus Walleij <linus.walleij@xxxxxxxxxx>]

On Fri, Mar 1, 2019 at 4:59 AM Marek Behún <marek.behun@xxxxxx> wrote:

> Add sysfs ABI documentation for the attribute files module_id,
> module_name, input_value and output_value of Moxtet devices.
>
> Signed-off-by: Marek Behún <marek.behun@xxxxxx>

(...)
> +++ b/Documentation/ABI/testing/sysfs-bus-moxtet-devices
> @@ -0,0 +1,25 @@
> +What:          /sys/bus/moxtet/devices/moxtet-<name>.<addr>/module_id
> +Date:          March 2019
> +KernelVersion: 5.2
> +Contact:       Marek Behún <marek.behun@xxxxxx>
> +Description:   (R) Moxtet module ID. Format: %x
> +
> +What:          /sys/bus/moxtet/devices/moxtet-<name>.<addr>/module_name
> +Date:          March 2019
> +KernelVersion: 5.2
> +Contact:       Marek Behún <marek.behun@xxxxxx>
> +Description:   (R) Moxtet module name. Format: string

These look good.

> +What:          /sys/bus/moxtet/devices/moxtet-<name>.<addr>/input_value
> +Date:          March 2019
> +KernelVersion: 5.2
> +Contact:       Marek Behún <marek.behun@xxxxxx>
> +Description:   (R) Read input value from module at this Moxtet address.
> +               Format: %x
> +
> +What:          /sys/bus/moxtet/devices/moxtet-<name>.<addr>/output_value
> +Date:          March 2019
> +KernelVersion: 5.2
> +Contact:       Marek Behún <marek.behun@xxxxxx>
> +Description:   (RW) Read last written value or write value to the module on
> +               this Moxtet address. Format: %x

What is the usecase for these?

If this is for debugging it should be in debugfs rather than in sysfs.

If it is here for random userspace drivers, we need some good explanation
as to why they can't just be kernel drivers.

Yours,
Linus Walleij