Re: [PATCH v2 4/4] drm: renesas: rzg2l_mipi_dsi: Increase reset deassertion delay to 1 msec

[Hugo Villeneuve <hugo@hugovil.com>]

Hi Biju,

On Thu, 19 Mar 2026 16:48:28 +0000
Biju <biju.das.au@gmail.com> wrote:

> From: Biju Das <biju.das.jz@bp.renesas.com>
> 
> The RZ/G2L hardware manual (Rev. 1.50, May 2025), Section 34.4.2.1,
> requires waiting more than 1 msec after deasserting the CMN_RSTB signal
> before the DSI-Tx module is ready. Increase the delay from 1 usec to
> 1 msec by replacing udelay(1) with fsleep(1000).
> 
> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>

In your first submission, I commented that "...this should be backported
to stable branches (missing Fixes / Cc: stable tags)?" and you answered
with "Agreed, will add fixes/stable tags".

If you still agree, this patch should be #3 in your list, so that it is
easier/straightforward to backport to stable branches.


> ---
> v1->v2:
>  * Updated commit header and description.
> ---
>  drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> index 5020be0f72ac..715872130780 100644
> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> @@ -807,7 +807,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
>  		if (ret < 0)
>  			goto err_phy;
>  
> -		udelay(1);
> +		fsleep(1000);
>  	}
>  
>  	return 0;
> -- 
> 2.43.0
> 
> 


-- 
Hugo Villeneuve