[PATCH v2 01/10] drm/exynos/decon5433: use readl_poll_timeout helpers

[Tobias Jakobi]

Hello Andrzej,


Andrzej Hajda wrote:
> Linux core provide helpers for polling with timeout, lets use them.
> 
> Signed-off-by: Andrzej Hajda <a.hajda at samsung.com>
> ---
>  drivers/gpu/drm/exynos/exynos5433_drm_decon.c | 20 ++++++++------------
>  1 file changed, 8 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/gpu/drm/exynos/exynos5433_drm_decon.c b/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
> index 5792ca88..237b4c9 100644
> --- a/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
> +++ b/drivers/gpu/drm/exynos/exynos5433_drm_decon.c
> @@ -13,6 +13,7 @@
>  #include <linux/platform_device.h>
>  #include <linux/clk.h>
>  #include <linux/component.h>
> +#include <linux/iopoll.h>
>  #include <linux/mfd/syscon.h>
>  #include <linux/of_device.h>
>  #include <linux/of_gpio.h>
> @@ -407,24 +408,19 @@ static void decon_atomic_flush(struct exynos_drm_crtc *crtc)
>  
>  static void decon_swreset(struct decon_context *ctx)
>  {
> -	unsigned int tries;
>  	unsigned long flags;
> +	u32 val;
> +	int ret;
>  
>  	writel(0, ctx->addr + DECON_VIDCON0);
> -	for (tries = 2000; tries; --tries) {
> -		if (~readl(ctx->addr + DECON_VIDCON0) & VIDCON0_STOP_STATUS)
> -			break;
> -		udelay(10);
> -	}
> +	readl_poll_timeout(ctx->addr + DECON_VIDCON0, val,
> +			   ~val & VIDCON0_STOP_STATUS, 12, 20000);
Wouldn't it be more consistent to also check for a timeout here?

With best wishes,
Tobias



>  	writel(VIDCON0_SWRESET, ctx->addr + DECON_VIDCON0);
> -	for (tries = 2000; tries; --tries) {
> -		if (~readl(ctx->addr + DECON_VIDCON0) & VIDCON0_SWRESET)
> -			break;
> -		udelay(10);
> -	}
> +	ret = readl_poll_timeout(ctx->addr + DECON_VIDCON0, val,
> +				 ~val & VIDCON0_SWRESET, 12, 20000);
>  
> -	WARN(tries == 0, "failed to software reset DECON\n");
> +	WARN(ret < 0, "failed to software reset DECON\n");
>  
>  	spin_lock_irqsave(&ctx->vblank_lock, flags);
>  	ctx->frame_id = 0;
>