[PATCH 1/2] video: s3c-fb: clear SHADOWCON register when clearing hardware window registers

[PATCH 1/2] video: s3c-fb: clear SHADOWCON register when clearing hardware window registers

[Jingoo Han]

All bits of SHADOWCON register should be cleared when clearing
hardware window registers; however, some bits of SHADOWCON register
are not cleared previously.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
---
 drivers/video/s3c-fb.c |   10 ++++++++--
 1 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/video/s3c-fb.c b/drivers/video/s3c-fb.c
index 5f9d8e6..b5c2939 100644
--- a/drivers/video/s3c-fb.c
+++ b/drivers/video/s3c-fb.c
@@ -1348,8 +1348,14 @@ static void s3c_fb_clear_win(struct s3c_fb *sfb, int win)
 	writel(0, regs + VIDOSD_A(win, sfb->variant));
 	writel(0, regs + VIDOSD_B(win, sfb->variant));
 	writel(0, regs + VIDOSD_C(win, sfb->variant));
-	reg = readl(regs + SHADOWCON);
-	writel(reg & ~SHADOWCON_WINx_PROTECT(win), regs + SHADOWCON);
+
+	if (sfb->variant.has_shadowcon) {
+		reg = readl(sfb->regs + SHADOWCON);
+		reg &= ~(SHADOWCON_WINx_PROTECT(win) |
+			SHADOWCON_CHx_ENABLE(win) |
+			SHADOWCON_CHx_LOCAL_ENABLE(win));
+		writel(reg, sfb->regs + SHADOWCON);
+	}
 }
 
 static int __devinit s3c_fb_probe(struct platform_device *pdev)
-- 
1.7.1

Re: [PATCH 1/2] video: s3c-fb: clear SHADOWCON register when clearing hardware window registers

[Florian Tobias Schandinat]

On 06/11/2012 02:26 AM, Jingoo Han wrote:
> All bits of SHADOWCON register should be cleared when clearing
> hardware window registers; however, some bits of SHADOWCON register
> are not cleared previously.

A bit more detailed description of what this might cause would be good.
I assume you are fixing this because it is more correct but there are no
known bugs related to this? Anyway, please try to give more information
next time.

> 
> Signed-off-by: Jingoo Han <jg1.han@samsung.com>

Applied both patches.


Thanks,

Florian Tobias Schandinat

> ---
>  drivers/video/s3c-fb.c |   10 ++++++++--
>  1 files changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/video/s3c-fb.c b/drivers/video/s3c-fb.c
> index 5f9d8e6..b5c2939 100644
> --- a/drivers/video/s3c-fb.c
> +++ b/drivers/video/s3c-fb.c
> @@ -1348,8 +1348,14 @@ static void s3c_fb_clear_win(struct s3c_fb *sfb, int win)
>  	writel(0, regs + VIDOSD_A(win, sfb->variant));
>  	writel(0, regs + VIDOSD_B(win, sfb->variant));
>  	writel(0, regs + VIDOSD_C(win, sfb->variant));
> -	reg = readl(regs + SHADOWCON);
> -	writel(reg & ~SHADOWCON_WINx_PROTECT(win), regs + SHADOWCON);
> +
> +	if (sfb->variant.has_shadowcon) {
> +		reg = readl(sfb->regs + SHADOWCON);
> +		reg &= ~(SHADOWCON_WINx_PROTECT(win) |
> +			SHADOWCON_CHx_ENABLE(win) |
> +			SHADOWCON_CHx_LOCAL_ENABLE(win));
> +		writel(reg, sfb->regs + SHADOWCON);
> +	}
>  }
>  
>  static int __devinit s3c_fb_probe(struct platform_device *pdev)