Hi everybody,

On 2024-08-27 17:25:14+0000, Thomas Weißschuh wrote:
> Introduce a device-managed variant of register_framebuffer() which
> automatically unregisters the framebuffer on device destruction.
> This can simplify the error handling and resource management in drivers.

Bert reported that this series broke his framebuffer ([0], [1]).

[0] https://lore.kernel.org/lkml/[email protected]/
[1] https://lore.kernel.org/lkml/[email protected]/

> Signed-off-by: Thomas Weißschuh <[email protected]>
> ---
>  drivers/video/fbdev/core/fbmem.c | 24 ++++++++++++++++++++++++
>  include/linux/fb.h               |  1 +
>  2 files changed, 25 insertions(+)
> 
> diff --git a/drivers/video/fbdev/core/fbmem.c 
> b/drivers/video/fbdev/core/fbmem.c
> index 4c4ad0a86a50..d17a2daa2483 100644
> --- a/drivers/video/fbdev/core/fbmem.c
> +++ b/drivers/video/fbdev/core/fbmem.c
> @@ -544,6 +544,30 @@ unregister_framebuffer(struct fb_info *fb_info)

[..]

> +/**
> + *   devm_register_framebuffer - resource-managed frame buffer device 
> registration
> + *   @dev: device the framebuffer belongs to
> + *   @fb_info: frame buffer info structure
> + *
> + *   Registers a frame buffer device @fb_info to device @dev.
> + *
> + *   Returns negative errno on error, or zero for success.
> + *
> + */
> +int
> +devm_register_framebuffer(struct device *dev, struct fb_info *fb_info)
> +{
> +     return devm_add_action_or_reset(dev, devm_unregister_framebuffer, 
> fb_info);
> +}
> +EXPORT_SYMBOL(devm_register_framebuffer);

This implementation is wrong, it never actually registers the
framebuffer. It should look like this:

int
devm_register_framebuffer(struct device *dev, struct fb_info *fb_info)
{
        int ret;

        ret = register_framebuffer(fb_info);
        if (ret)
                return ret;

        return devm_add_action_or_reset(dev, devm_unregister_framebuffer, 
fb_info);
}
EXPORT_SYMBOL(devm_register_framebuffer);

Bert, could you test this?
Helge, do you want me to resend the series, minus the original patch 1?

Reply via email to