Re: [PATCH v2 03/21] of: Rename of_modalias_node()

[Miquel Raynal]

Hi Rob,

robh@xxxxxxxxxx wrote on Tue, 7 Mar 2023 18:19:03 -0600:

> On Tue, Mar 07, 2023 at 05:53:41PM +0100, Miquel Raynal wrote:
> > This helper does not produce a real modalias, but tries to get the
> > "product" compatible part of the "vendor,product" compatibles only. It
> > is far from creating a purely useful modalias string and does not seem
> > to be used like that directly anyway, so let's try to give this helper a
> > more meaningful name before moving there a real modalias helper (already
> > existing under of/device.c).
> > 
> > Also update the various documentations to refer to the strings as
> > "aliases" rather than "modaliases" which has a real meaning in the Linux
> > kernel.
> > 
> > There is no functional change.
> > 
> > Cc: Rafael J. Wysocki <rafael@xxxxxxxxxx>
> > Cc: Len Brown <lenb@xxxxxxxxxx>
> > Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
> > Cc: Maxime Ripard <mripard@xxxxxxxxxx>
> > Cc: Thomas Zimmermann <tzimmermann@xxxxxxx>
> > Cc: Sebastian Reichel <sre@xxxxxxxxxx>
> > Cc: Wolfram Sang <wsa@xxxxxxxxxx>
> > Cc: Mark Brown <broonie@xxxxxxxxxx>
> > Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
> > ---
> >  drivers/acpi/bus.c                |  7 ++++---
> >  drivers/gpu/drm/drm_mipi_dsi.c    |  2 +-
> >  drivers/hsi/hsi_core.c            |  2 +-  
> 
> These should not have been using this function. The matching on just the 
> product was a relic from I2C and SPI which we don't want to propogate. 
> No clue why ACPI needed it...
> 
> If you respin or want to fixup while applying, can you add a kerneldoc 
> comment to not add new users of the function. Not that anyone will 
> follow that... :(

I extensively scratched my forehead while trying to understand the use
of this function. I've added this to my v3:

  * It does this by stripping the manufacturer prefix (as delimited by a ',')
  * from the first entry in the compatible list property.
  *
+ * Note: The matching on just the "product" side of the compatible is a relic
+ * from I2C and SPI. Please do not add any new user.
+ *
  * Return: This routine returns 0 on success, <0 on failure.
  */

> Reviewed-by: Rob Herring <robh@xxxxxxxxxx>
> 
> >  drivers/i2c/busses/i2c-powermac.c |  2 +-
> >  drivers/i2c/i2c-core-of.c         |  2 +-
> >  drivers/of/base.c                 | 15 ++++++++-------
> >  drivers/spi/spi.c                 |  4 ++--
> >  include/linux/of.h                |  2 +-
> >  8 files changed, 19 insertions(+), 17 deletions(-)  


Thanks,
Miquèl