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

From: Chen-Yu Tsai
Date: Wed Sep 11 2024 - 03:38:00 EST


On Mon, Sep 9, 2024 at 10:45 AM Chen-Yu Tsai <wenst@xxxxxxxxxxxx> wrote:
>
> 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.

FTR this patch ended up getting dropped from the series as it was no
longer needed. However if folks think there is still value in this patch,
I can still send a new version.


ChenYu