Re: [PATCH v2 02/12] drm/armada: Use regular fbdev I/O helpers

[Sam Ravnborg <sam@ravnborg.org>]

Hi Thomas,

On Mon, May 15, 2023 at 11:40:23AM +0200, Thomas Zimmermann wrote:
> Use the regular fbdev helpers for framebuffer I/O instead of DRM's
> helpers. Armada does not use damage handling, so DRM's fbdev helpers
> are mere wrappers around the fbdev code.
> 
> By using fbdev helpers directly within each DRM fbdev emulation,
> we can eventually remove DRM's wrapper functions entirely.
> 
> v2:
> 	* use FB_IO_HELPERS option
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> Cc: Russell King <linux@armlinux.org.uk>
> ---
>  drivers/gpu/drm/armada/Kconfig        | 1 +
>  drivers/gpu/drm/armada/armada_fbdev.c | 9 ++++-----
>  2 files changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/armada/Kconfig b/drivers/gpu/drm/armada/Kconfig
> index f5c66d89ba99..5afade25e217 100644
> --- a/drivers/gpu/drm/armada/Kconfig
> +++ b/drivers/gpu/drm/armada/Kconfig
> @@ -3,6 +3,7 @@ config DRM_ARMADA
>  	tristate "DRM support for Marvell Armada SoCs"
>  	depends on DRM && HAVE_CLK && ARM && MMU
>  	select DRM_KMS_HELPER
> +	select FB_IO_HELPERS if DRM_FBDEV_EMULATION
>  	help
>  	  Support the "LCD" controllers found on the Marvell Armada 510
>  	  devices.  There are two controllers on the device, each controller
> diff --git a/drivers/gpu/drm/armada/armada_fbdev.c b/drivers/gpu/drm/armada/armada_fbdev.c
> index 0a5fd1aa86eb..6c3bbaf53569 100644
> --- a/drivers/gpu/drm/armada/armada_fbdev.c
> +++ b/drivers/gpu/drm/armada/armada_fbdev.c
> @@ -5,6 +5,7 @@
>   */
>  
>  #include <linux/errno.h>
> +#include <linux/fb.h>
>  #include <linux/kernel.h>
>  #include <linux/module.h>
>  
> @@ -34,11 +35,9 @@ static void armada_fbdev_fb_destroy(struct fb_info *info)
>  static const struct fb_ops armada_fb_ops = {
>  	.owner		= THIS_MODULE,
>  	DRM_FB_HELPER_DEFAULT_OPS,
> -	.fb_read	= drm_fb_helper_cfb_read,
> -	.fb_write	= drm_fb_helper_cfb_write,
I had expected to see
.fb_read = fb_io_read,

But maybe this only used when using damage handling?

Likewise for drm_fb_helper_cfb_write.

??

> -	.fb_fillrect	= drm_fb_helper_cfb_fillrect,
> -	.fb_copyarea	= drm_fb_helper_cfb_copyarea,
> -	.fb_imageblit	= drm_fb_helper_cfb_imageblit,
> +	.fb_fillrect	= cfb_fillrect,
> +	.fb_copyarea	= cfb_copyarea,
> +	.fb_imageblit	= cfb_imageblit,

This part is as expected.

	Sam

>  	.fb_destroy	= armada_fbdev_fb_destroy,
>  };
>  
> -- 
> 2.40.1