[PATCH] drm: xlnx: add <linux/io.h> for readl/writel

[Ville Syrjälä]

On Wed, Jul 06, 2022 at 11:42:24AM -0700, Randy Dunlap wrote:
> Add a header file to prevent build errors:
> 
> ../drivers/gpu/drm/xlnx/zynqmp_dp.c: In function ‘zynqmp_dp_write’:
> ../drivers/gpu/drm/xlnx/zynqmp_dp.c:335:9: error: implicit declaration of function ‘writel’ [-Werror=implicit-function-declaration]
>   335 |         writel(val, dp->iomem + offset);
> ../drivers/gpu/drm/xlnx/zynqmp_dp.c: In function ‘zynqmp_dp_read’:
> ../drivers/gpu/drm/xlnx/zynqmp_dp.c:340:16: error: implicit declaration of function ‘readl’ [-Werror=implicit-function-declaration]
>   340 |         return readl(dp->iomem + offset);
> 
> Fixes: d76271d22694 ("drm: xlnx: DRM/KMS driver for Xilinx ZynqMP DisplayPort Subsystem")

Should be
Fixes: a204f9743b68 ("drm: Remove linux/i2c.h from drm_crtc.h")
probably?

allmodconfig caught a few other drivers needing io.h but somehow
this one built for me without that header on both arm and x86.
Was this on some other architecture, or maybe there's some weird
config dependency that pulls in io.h for allmodconfig?

> Signed-off-by: Randy Dunlap <rdunlap at infradead.org>
> Cc: Hyun Kwon <hyun.kwon at xilinx.com>
> Cc: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> Cc: "Ville Syrjälä" <ville.syrjala at linux.intel.com>
> Cc: David Airlie <airlied at linux.ie>
> Cc: Daniel Vetter <daniel at ffwll.ch>
> Cc: Michal Simek <michal.simek at xilinx.com>
> Cc: linux-arm-kernel at lists.infradead.org
> ---
>  drivers/gpu/drm/xlnx/zynqmp_dp.c |    1 +
>  1 file changed, 1 insertion(+)
> 
> --- a/drivers/gpu/drm/xlnx/zynqmp_dp.c
> +++ b/drivers/gpu/drm/xlnx/zynqmp_dp.c
> @@ -25,6 +25,7 @@
>  #include <linux/clk.h>
>  #include <linux/delay.h>
>  #include <linux/device.h>
> +#include <linux/io.h>
>  #include <linux/module.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_runtime.h>

-- 
Ville Syrjälä
Intel