Re: [PATCH v2] fbdev: sh_mobile_lcdcfb: Restore the per-overlay sysfs attributes

[Helge Deller <deller@gmx.de>]

On 9/12/26 12:21, Karl Mehltretter wrote:
> The ovl_* files documented in
> Documentation/ABI/testing/sysfs-devices-platform-sh_mobile_lcdc_fb no
> longer exist.
> 
> Commit a979182a2453 ("fbdev: lcdcfb: Register sysfs groups through driver
> core") moved the attributes from each overlay's framebuffer device to
> the platform driver's dev_groups and renamed them overlay_*. There is
> now only one set of attributes for the whole LCDC. The callbacks still
> expect dev_get_drvdata() to return a struct fb_info, but the platform
> device holds struct sh_mobile_lcdc_priv, so they access the wrong
> structure.
> 
> Restore the documented names and register the group on each overlay's
> framebuffer device with device_add_groups(). Remove it with
> device_remove_groups() before unregistering the framebuffer. Skip
> creation when dev_of_fbinfo(info) is NULL, as the old device_create_file()
> calls did.
> 
> Drop the CONFIG_FB_DEVICE guard, since the driver already depends on it.
> 
> Fixes: a979182a2453 ("fbdev: lcdcfb: Register sysfs groups through driver core")
> Cc: stable@vger.kernel.org
> Assisted-by: LLM
> Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com>
> ---
> Changes in v2:
> - Use dev_of_fbinfo() for overlay sysfs registration and removal (Helge).
> 
> v1: https://lore.kernel.org/r/20260907021844.25497-1-kmehltretter@gmail.com/
> 
> Found while reviewing the sysfs ABI documentation. Shixiong confirmed
> that using the platform driver's dev_groups is wrong here.
> 
> Compile-tested with Clang 22.1.8, ARCH=arm and W=1, using multi_v7_defconfig
> with COMPILE_TEST=y, FB_DEVICE=y and FB_SH_MOBILE_LCDC=m.
> 
> Also checked FB_DEVICE=n: olddefconfig disables FB_SH_MOBILE_LCDC because
> of its existing Kconfig dependency, and the framebuffer core compiles.
> This does not test the driver with FB_DEVICE=n; removing that dependency
> requires additional changes outside the overlay sysfs paths.
> 
> No runtime test; I have no SH-Mobile hardware.
> 
>   drivers/video/fbdev/sh_mobile_lcdcfb.c | 39 +++++++++++++++++---------
>   1 file changed, 25 insertions(+), 14 deletions(-)
applied.

Thanks!
Helge