Re: [PATCH v6 06/12] gpiolib: Add gpio_get_property_name_length()

[Chen-Yu Tsai]

On Wed, Sep 4, 2024 at 9:40 PM Andy Shevchenko
<andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
>
> On Wed, Sep 04, 2024 at 05:00:08PM +0800, Chen-Yu Tsai wrote:
> > The I2C device tree component prober needs to get and toggle GPIO lines
> > for the components it intends to probe. These components may not use the
> > same name for their GPIO lines, so the prober must go through the device
> > tree, check each property to see it is a GPIO property, and get the GPIO
> > line.
> >
> > Instead of duplicating the GPIO suffixes, or exporting them to the
> > prober to do pattern matching, simply add and export a new function that
> > does the pattern matching and returns the length of the GPIO name. The
> > caller can then use that to copy out the name if it needs to.
>
> > Andy suggested a much shorter implementation.
>
> No need to have this sentence in the commit message, changelog area is fine.
> But if you wish... :-)

It does seem out of place without any context. I'll move it to the
changelog area. :D

> > Suggested-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> > Signed-off-by: Chen-Yu Tsai <wenst@xxxxxxxxxxxx>
>
> ...
>
> > +/**
> > + * gpio_get_property_name_length - Returns the GPIO name length from a property name
> > + * @propname:        name of the property to check
> > + *
> > + * This function checks if the given property name matches the GPIO property
> > + * patterns, and returns the length of the name of the GPIO. The pattern is
> > + * "*-<GPIO suffix>" or just "<GPIO suffix>".
> > + *
> > + * Returns:
> > + * The length of the string before '-<GPIO suffix>' if it matches
> > + * "*-<GPIO suffix>", or 0 if no name part, just the suffix, or
> > + * -EINVAL if the string doesn't match the pattern.
>
> Should be %-EINVAL as we agreed with Bart when I updated GPIOLIB kernel-doc.

Ack.

In the regulator cleanups I did, I used -%EINVAL instead. But then I
realized that constants aren't really cross-referenced. I probably
have to go through all of them to fix those up.


ChenYu