[PATCH] drm/stm: Remove usage of drm_display_mode_to_videomode()

[Yannick FERTRE]

Hi Marek,
thanks for the patch. It works fine on stm32mp1 eval board with bridge 
DSI & DPI panel.

Tested-by: Yannick Fertré <yannick.fertre at st.com>

Best regards

On 12/24/20 7:20 AM, Marek Vasut wrote:
> There is not much value in the extra conversion step, the calculations
> required for the LTDC IP are different than what is used in the
> drm_display_mode_to_videomode(), so just do the right ones in the LTDC
> driver right away.
> 
> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Alexandre Torgue <alexandre.torgue at st.com>
> Cc: Antonio Borneo <antonio.borneo at st.com>
> Cc: Benjamin Gaignard <benjamin.gaignard at st.com>
> Cc: Maxime Coquelin <mcoquelin.stm32 at gmail.com>
> Cc: Philippe Cornu <philippe.cornu at st.com>
> Cc: Sam Ravnborg <sam at ravnborg.org>
> Cc: Vincent Abriou <vincent.abriou at st.com>
> Cc: Yannick Fertre <yannick.fertre at st.com>
> Cc: linux-arm-kernel at lists.infradead.org
> Cc: linux-stm32 at st-md-mailman.stormreply.com
> To: dri-devel at lists.freedesktop.org
> ---
>   drivers/gpu/drm/stm/ltdc.c | 33 +++++++++++++++++----------------
>   1 file changed, 17 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
> index 22c7e9fa5ab7..e8fc8fc50d94 100644
> --- a/drivers/gpu/drm/stm/ltdc.c
> +++ b/drivers/gpu/drm/stm/ltdc.c
> @@ -545,7 +545,6 @@ static void ltdc_crtc_mode_set_nofb(struct drm_crtc *crtc)
>   	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
>   	struct drm_device *ddev = crtc->dev;
>   	struct drm_display_mode *mode = &crtc->state->adjusted_mode;
> -	struct videomode vm;
>   	u32 bus_flags = 0;
>   	u32 hsync, vsync, accum_hbp, accum_vbp, accum_act_w, accum_act_h;
>   	u32 total_width, total_height;
> @@ -565,31 +564,33 @@ static void ltdc_crtc_mode_set_nofb(struct drm_crtc *crtc)
>   		}
>   	}
>   
> -	drm_display_mode_to_videomode(mode, &vm);
> -
>   	DRM_DEBUG_DRIVER("CRTC:%d mode:%s\n", crtc->base.id, mode->name);
> -	DRM_DEBUG_DRIVER("Video mode: %dx%d", vm.hactive, vm.vactive);
> +	DRM_DEBUG_DRIVER("Video mode: %dx%d", mode->hdisplay, mode->vdisplay);
>   	DRM_DEBUG_DRIVER(" hfp %d hbp %d hsl %d vfp %d vbp %d vsl %d\n",
> -			 vm.hfront_porch, vm.hback_porch, vm.hsync_len,
> -			 vm.vfront_porch, vm.vback_porch, vm.vsync_len);
> +			 mode->hsync_start - mode->hdisplay,
> +			 mode->htotal - mode->hsync_end,
> +			 mode->hsync_end - mode->hsync_start,
> +			 mode->vsync_start - mode->vdisplay,
> +			 mode->vtotal - mode->vsync_end,
> +			 mode->vsync_end - mode->vsync_start);
>   
>   	/* Convert video timings to ltdc timings */
> -	hsync = vm.hsync_len - 1;
> -	vsync = vm.vsync_len - 1;
> -	accum_hbp = hsync + vm.hback_porch;
> -	accum_vbp = vsync + vm.vback_porch;
> -	accum_act_w = accum_hbp + vm.hactive;
> -	accum_act_h = accum_vbp + vm.vactive;
> -	total_width = accum_act_w + vm.hfront_porch;
> -	total_height = accum_act_h + vm.vfront_porch;
> +	hsync = mode->hsync_end - mode->hsync_start - 1;
> +	vsync = mode->vsync_end - mode->vsync_start - 1;
> +	accum_hbp = mode->htotal - mode->hsync_start - 1;
> +	accum_vbp = mode->vtotal - mode->vsync_start - 1;
> +	accum_act_w = accum_hbp + mode->hdisplay;
> +	accum_act_h = accum_vbp + mode->vdisplay;
> +	total_width = mode->htotal - 1;
> +	total_height = mode->vtotal - 1;
>   
>   	/* Configures the HS, VS, DE and PC polarities. Default Active Low */
>   	val = 0;
>   
> -	if (vm.flags & DISPLAY_FLAGS_HSYNC_HIGH)
> +	if (mode->flags & DRM_MODE_FLAG_PHSYNC)
>   		val |= GCR_HSPOL;
>   
> -	if (vm.flags & DISPLAY_FLAGS_VSYNC_HIGH)
> +	if (mode->flags & DRM_MODE_FLAG_PVSYNC)
>   		val |= GCR_VSPOL;
>   
>   	if (bus_flags & DRM_BUS_FLAG_DE_LOW)
>