Re: [PATCH] drm/stm: ltdc: rework reset sequence

From: Philippe CORNU
Date: Tue Jul 03 2018 - 07:02:52 EST


Hi Yannick,


On 06/29/2018 01:22 PM, Yannick Fertre wrote:
> Reset must be properly assert before deassert.
> This is important if there is an early boot splash screen
> before the kernel start up.
>
> Signed-off-by: Yannick Fertre <yannick.fertre@xxxxxx>
> ---
> drivers/gpu/drm/stm/ltdc.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
> index 96d20c2..8f4606d 100644
> --- a/drivers/gpu/drm/stm/ltdc.c
> +++ b/drivers/gpu/drm/stm/ltdc.c
> @@ -1130,8 +1130,11 @@ int ltdc_load(struct drm_device *ddev)
> }
> }
>
> - if (!IS_ERR(rstc))
> + if (!IS_ERR(rstc)) {
> + reset_control_assert(rstc);
> + usleep_range(10, 20);
> reset_control_deassert(rstc);
> + }

Thank you for your patch,

Reviewed-by: Philippe Cornu <philippe.cornu@xxxxxx>
Tested-by: Philippe Cornu <philippe.cornu@xxxxxx>

Philippe :-)

>
> /* Disable interrupts */
> reg_clear(ldev->regs, LTDC_IER,
>