Re: [PATCH] drm/stm: ltdc: reset controller to avoid partial refresh

[Philippe CORNU <philippe.cornu@st.com>]

On 4/3/19 11:24 AM, Yannick Fertré wrote:
> Display controller reset must be done as soon as possible after enable
> the clock to avoid partial refresh on screen.
> 
> Signed-off-by: Yannick Fertré <yannick.fertre@st.com>
> ---
>   drivers/gpu/drm/stm/ltdc.c | 12 ++++++------
>   1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
> index 32fd6a3..7bbe61c 100644
> --- a/drivers/gpu/drm/stm/ltdc.c
> +++ b/drivers/gpu/drm/stm/ltdc.c
> @@ -1134,6 +1134,12 @@ int ltdc_load(struct drm_device *ddev)
>   		return -ENODEV;
>   	}
>   
> +	if (!IS_ERR(rstc)) {
> +		reset_control_assert(rstc);
> +		usleep_range(10, 20);
> +		reset_control_deassert(rstc);
> +	}
> +
>   	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>   	ldev->regs = devm_ioremap_resource(dev, res);
>   	if (IS_ERR(ldev->regs)) {
> @@ -1156,12 +1162,6 @@ int ltdc_load(struct drm_device *ddev)
>   		}
>   	}
>   
> -	if (!IS_ERR(rstc)) {
> -		reset_control_assert(rstc);
> -		usleep_range(10, 20);
> -		reset_control_deassert(rstc);
> -	}
> -

Dear Yannick,
Thank you for your patch,

Acked-by: Philippe Cornu <philippe.cornu@st.com>

Philippe :)

>   	/* Disable interrupts */
>   	reg_clear(ldev->regs, LTDC_IER,
>   		  IER_LIE | IER_RRIE | IER_FUIE | IER_TERRIE);
>