drm/bridge: tc358768: Use struct videomode

The TC358768 documentation uses HFP, HBP, etc. values to deal with the
video mode, while the driver currently uses the DRM display mode
(htotal, hsync_start, etc).

Change the driver to convert the DRM display mode to struct videomode,
which then allows us to use the same units the documentation uses. This
makes it much easier to work on the code when using the TC358768
documentation as a reference.
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Tested-by: Maxim Schwalm <maxim.schwalm@gmail.com> # Asus TF700T
Tested-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230906-tc358768-v4-6-31725f008a50@ideasonboard.com

drivers/gpu/drm/bridge/tc358768.c

@@ -650,6 +650,7 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge)
 	u32 dsiclk, dsibclk, video_start;
 	const u32 internal_delay = 40;
 	int ret, i;
+	struct videomode vm;
 
 	if (mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS) {
 		dev_warn_once(priv->dev, "Non-continuous mode unimplemented, falling back to continuous\n");
@@ -673,6 +674,8 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge)
 		return;
 	}
 
+	drm_display_mode_to_videomode(mode, &vm);
+
 	dsiclk = priv->dsiclk;
 	dsibclk = dsiclk / 4;
 
@@ -681,28 +684,28 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge)
 	switch (dsi_dev->format) {
 	case MIPI_DSI_FMT_RGB888:
 		val |= (0x3 << 4);
-		hact = mode->hdisplay * 3;
-		video_start = (mode->htotal - mode->hsync_start) * 3;
+		hact = vm.hactive * 3;
+		video_start = (vm.hsync_len + vm.hback_porch) * 3;
 		data_type = MIPI_DSI_PACKED_PIXEL_STREAM_24;
 		break;
 	case MIPI_DSI_FMT_RGB666:
 		val |= (0x4 << 4);
-		hact = mode->hdisplay * 3;
-		video_start = (mode->htotal - mode->hsync_start) * 3;
+		hact = vm.hactive * 3;
+		video_start = (vm.hsync_len + vm.hback_porch) * 3;
 		data_type = MIPI_DSI_PACKED_PIXEL_STREAM_18;
 		break;
 
 	case MIPI_DSI_FMT_RGB666_PACKED:
 		val |= (0x4 << 4) | BIT(3);
-		hact = mode->hdisplay * 18 / 8;
-		video_start = (mode->htotal - mode->hsync_start) * 18 / 8;
+		hact = vm.hactive * 18 / 8;
+		video_start = (vm.hsync_len + vm.hback_porch) * 18 / 8;
 		data_type = MIPI_DSI_PIXEL_STREAM_3BYTE_18;
 		break;
 
 	case MIPI_DSI_FMT_RGB565:
 		val |= (0x5 << 4);
-		hact = mode->hdisplay * 2;
-		video_start = (mode->htotal - mode->hsync_start) * 2;
+		hact = vm.hactive * 2;
+		video_start = (vm.hsync_len + vm.hback_porch) * 2;
 		data_type = MIPI_DSI_PACKED_PIXEL_STREAM_16;
 		break;
 	default:
@@ -814,43 +817,43 @@ static void tc358768_bridge_pre_enable(struct drm_bridge *bridge)
 		tc358768_write(priv, TC358768_DSI_EVENT, 0);
 
 		/* vact */
-		tc358768_write(priv, TC358768_DSI_VACT, mode->vdisplay);
+		tc358768_write(priv, TC358768_DSI_VACT, vm.vactive);
 
 		/* vsw */
-		tc358768_write(priv, TC358768_DSI_VSW,
-			       mode->vsync_end - mode->vsync_start);
+		tc358768_write(priv, TC358768_DSI_VSW, vm.vsync_len);
+
 		/* vbp */
-		tc358768_write(priv, TC358768_DSI_VBPR,
-			       mode->vtotal - mode->vsync_end);
+		tc358768_write(priv, TC358768_DSI_VBPR, vm.vback_porch);
 
 		/* hsw * byteclk * ndl / pclk */
-		val = (u32)div_u64((mode->hsync_end - mode->hsync_start) *
+		val = (u32)div_u64(vm.hsync_len *
 				   ((u64)priv->dsiclk / 4) * priv->dsi_lanes,
-				   mode->clock * 1000);
+				   vm.pixelclock);
 		tc358768_write(priv, TC358768_DSI_HSW, val);
 
 		/* hbp * byteclk * ndl / pclk */
-		val = (u32)div_u64((mode->htotal - mode->hsync_end) *
+		val = (u32)div_u64(vm.hback_porch *
 				   ((u64)priv->dsiclk / 4) * priv->dsi_lanes,
-				   mode->clock * 1000);
+				   vm.pixelclock);
 		tc358768_write(priv, TC358768_DSI_HBPR, val);
 	} else {
 		/* Set event mode */
 		tc358768_write(priv, TC358768_DSI_EVENT, 1);
 
 		/* vact */
-		tc358768_write(priv, TC358768_DSI_VACT, mode->vdisplay);
+		tc358768_write(priv, TC358768_DSI_VACT, vm.vactive);
 
 		/* vsw (+ vbp) */
 		tc358768_write(priv, TC358768_DSI_VSW,
-			       mode->vtotal - mode->vsync_start);
+			       vm.vsync_len + vm.vback_porch);
+
 		/* vbp (not used in event mode) */
 		tc358768_write(priv, TC358768_DSI_VBPR, 0);
 
 		/* (hsw + hbp) * byteclk * ndl / pclk */
-		val = (u32)div_u64((mode->htotal - mode->hsync_start) *
+		val = (u32)div_u64((vm.hsync_len + vm.hback_porch) *
 				   ((u64)priv->dsiclk / 4) * priv->dsi_lanes,
-				   mode->clock * 1000);
+				   vm.pixelclock);
 		tc358768_write(priv, TC358768_DSI_HSW, val);
 
 		/* hbp (not used in event mode) */