Re: [PATCH v2] drm/stm: ltdc: remove clk_round_rate comment

From: Philippe CORNU
Date: Mon May 13 2019 - 10:47:43 EST


Dear Yannick,

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

Thank you,

Philippe :-)

On 5/13/19 3:15 PM, Yannick Fertrà wrote:
> Clk_round_rate returns rounded clock without changing
> the hardware in any way.
> This function couldn't replace set_rate/get_rate calls.
> Todo comment has been removed & a new log inserted.
>
> Signed-off-by: Yannick Fertrà <yannick.fertre@xxxxxx>
> ---
> Changes in v2:
> - Clk_enable & clk_disable are needed for the SOC STM32F7
> (not for STM32MP1). I return this part of the patch to make sure the
> driver is compatible with all SOC STM32.
>
> drivers/gpu/drm/stm/ltdc.c | 8 +++-----
> 1 file changed, 3 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
> index 97912e2..1104e78 100644
> --- a/drivers/gpu/drm/stm/ltdc.c
> +++ b/drivers/gpu/drm/stm/ltdc.c
> @@ -507,11 +507,6 @@ static bool ltdc_crtc_mode_fixup(struct drm_crtc *crtc,
> struct ltdc_device *ldev = crtc_to_ltdc(crtc);
> int rate = mode->clock * 1000;
>
> - /*
> - * TODO clk_round_rate() does not work yet. When ready, it can
> - * be used instead of clk_set_rate() then clk_get_rate().
> - */
> -
> clk_disable(ldev->pixel_clk);
> if (clk_set_rate(ldev->pixel_clk, rate) < 0) {
> DRM_ERROR("Cannot set rate (%dHz) for pixel clk\n", rate);
> @@ -521,6 +516,9 @@ static bool ltdc_crtc_mode_fixup(struct drm_crtc *crtc,
>
> adjusted_mode->clock = clk_get_rate(ldev->pixel_clk) / 1000;
>
> + DRM_DEBUG_DRIVER("requested clock %dkHz, adjusted clock %dkHz\n",
> + mode->clock, adjusted_mode->clock);
> +
> return true;
> }
>
> --
> 2.7.4
>