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

[Benjamin Gaignard]

2018-06-29 13:22 GMT+02:00 Yannick Fertre <yannick.fertre at st.com>:
> 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 at st.com>

Applied on drm-misc-next.
Thansk,
Benjamin

> ---
>  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);
> +       }
>
>         /* Disable interrupts */
>         reg_clear(ldev->regs, LTDC_IER,
> --
> 1.9.1
>