drm/i915/dsi: start using enum mipi_dsi_pixel_format

A small step moving us closer to DRM MIPI DSI code. Use enum
mipi_dsi_pixel_format instead of our own. The first benefit is being
able to use common mipi_dsi_pixel_format_to_bpp().

There's a little back and forth conversion with the VBT -> enum ->
register, since we have just shoved the VBT value into the register
directly. Longer term, all the VBT parsing and deciphering should be
done in intel_bios.c, and abstracted there.
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1458123700-16003-2-git-send-email-jani.nikula@intel.com

drivers/gpu/drm/i915/intel_dsi.c

@@ -787,7 +787,7 @@ static void set_dsi_timings(struct drm_encoder *encoder,
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
 	enum port port;
-	unsigned int bpp = dsi_pixel_format_bpp(intel_dsi->pixel_format);
+	unsigned int bpp = mipi_dsi_pixel_format_to_bpp(intel_dsi->pixel_format);
 	unsigned int lane_count = intel_dsi->lane_count;
 
 	u16 hactive, hfp, hsync, hbp, vfp, vsync, vbp;
@@ -849,6 +849,23 @@ static void set_dsi_timings(struct drm_encoder *encoder,
 	}
 }
 
+static u32 pixel_format_to_reg(enum mipi_dsi_pixel_format fmt)
+{
+	switch (fmt) {
+	case MIPI_DSI_FMT_RGB888:
+		return VID_MODE_FORMAT_RGB888;
+	case MIPI_DSI_FMT_RGB666:
+		return VID_MODE_FORMAT_RGB666;
+	case MIPI_DSI_FMT_RGB666_PACKED:
+		return VID_MODE_FORMAT_RGB666_PACKED;
+	case MIPI_DSI_FMT_RGB565:
+		return VID_MODE_FORMAT_RGB565;
+	default:
+		MISSING_CASE(fmt);
+		return VID_MODE_FORMAT_RGB666;
+	}
+}
+
 static void intel_dsi_prepare(struct intel_encoder *intel_encoder)
 {
 	struct drm_encoder *encoder = &intel_encoder->base;
@@ -858,7 +875,7 @@ static void intel_dsi_prepare(struct intel_encoder *intel_encoder)
 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
 	const struct drm_display_mode *adjusted_mode = &intel_crtc->config->base.adjusted_mode;
 	enum port port;
-	unsigned int bpp = dsi_pixel_format_bpp(intel_dsi->pixel_format);
+	unsigned int bpp = mipi_dsi_pixel_format_to_bpp(intel_dsi->pixel_format);
 	u32 val, tmp;
 	u16 mode_hdisplay;
 
@@ -917,9 +934,7 @@ static void intel_dsi_prepare(struct intel_encoder *intel_encoder)
 		val |= CMD_MODE_DATA_WIDTH_8_BIT; /* XXX */
 	} else {
 		val |= intel_dsi->channel << VID_MODE_CHANNEL_NUMBER_SHIFT;
-
-		/* XXX: cross-check bpp vs. pixel format? */
-		val |= intel_dsi->pixel_format;
+		val |= pixel_format_to_reg(intel_dsi->pixel_format);
 	}
 
 	tmp = 0;

drivers/gpu/drm/i915/intel_dsi.h

@@ -34,8 +34,6 @@
 #define DSI_DUAL_LINK_FRONT_BACK	1
 #define DSI_DUAL_LINK_PIXEL_ALT		2
 
-int dsi_pixel_format_bpp(int pixel_format);
-
 struct intel_dsi_host;
 
 struct intel_dsi {
@@ -64,8 +62,12 @@ struct intel_dsi {
 	/* number of DSI lanes */
 	unsigned int lane_count;
 
-	/* video mode pixel format for MIPI_DSI_FUNC_PRG register */
-	u32 pixel_format;
+	/*
+	 * video mode pixel format
+	 *
+	 * XXX: consolidate on .format in struct mipi_dsi_device.
+	 */
+	enum mipi_dsi_pixel_format pixel_format;
 
 	/* video mode format for MIPI_VIDEO_MODE_FORMAT register */
 	u32 video_mode_format;

drivers/gpu/drm/i915/intel_dsi_panel_vbt.c

@@ -412,6 +412,25 @@ static const struct drm_panel_funcs vbt_panel_funcs = {
 	.get_modes = vbt_panel_get_modes,
 };
 
+/* XXX: This should be done when parsing the VBT in intel_bios.c */
+static enum mipi_dsi_pixel_format pixel_format_from_vbt(u32 fmt)
+{
+	/* It just so happens the VBT matches register contents. */
+	switch (fmt) {
+	case VID_MODE_FORMAT_RGB888:
+		return MIPI_DSI_FMT_RGB888;
+	case VID_MODE_FORMAT_RGB666:
+		return MIPI_DSI_FMT_RGB666;
+	case VID_MODE_FORMAT_RGB666_PACKED:
+		return MIPI_DSI_FMT_RGB666_PACKED;
+	case VID_MODE_FORMAT_RGB565:
+		return MIPI_DSI_FMT_RGB565;
+	default:
+		MISSING_CASE(fmt);
+		return MIPI_DSI_FMT_RGB666;
+	}
+}
+
 struct drm_panel *vbt_panel_init(struct intel_dsi *intel_dsi, u16 panel_id)
 {
 	struct drm_device *dev = intel_dsi->base.base.dev;
@@ -420,7 +439,7 @@ struct drm_panel *vbt_panel_init(struct intel_dsi *intel_dsi, u16 panel_id)
 	struct mipi_pps_data *pps = dev_priv->vbt.dsi.pps;
 	struct drm_display_mode *mode = dev_priv->vbt.lfp_lvds_vbt_mode;
 	struct vbt_panel *vbt_panel;
-	u32 bits_per_pixel = 24;
+	u32 bpp;
 	u32 tlpx_ns, extra_byte_count, bitrate, tlpx_ui;
 	u32 ui_num, ui_den;
 	u32 prepare_cnt, exit_zero_cnt, clk_zero_cnt, trail_cnt;
@@ -436,12 +455,11 @@ struct drm_panel *vbt_panel_init(struct intel_dsi *intel_dsi, u16 panel_id)
 	intel_dsi->eotp_pkt = mipi_config->eot_pkt_disabled ? 0 : 1;
 	intel_dsi->clock_stop = mipi_config->enable_clk_stop ? 1 : 0;
 	intel_dsi->lane_count = mipi_config->lane_cnt + 1;
-	intel_dsi->pixel_format = mipi_config->videomode_color_format << 7;
+	intel_dsi->pixel_format = pixel_format_from_vbt(mipi_config->videomode_color_format << 7);
+	bpp = mipi_dsi_pixel_format_to_bpp(intel_dsi->pixel_format);
+
 	intel_dsi->dual_link = mipi_config->dual_link;
 	intel_dsi->pixel_overlap = mipi_config->pixel_overlap;
-
-	bits_per_pixel = dsi_pixel_format_bpp(intel_dsi->pixel_format);
-
 	intel_dsi->operation_mode = mipi_config->is_cmd_mode;
 	intel_dsi->video_mode_format = mipi_config->video_transfer_mode;
 	intel_dsi->escape_clk_div = mipi_config->byte_clk_sel;
@@ -475,8 +493,7 @@ struct drm_panel *vbt_panel_init(struct intel_dsi *intel_dsi, u16 panel_id)
 	 */
 	if (intel_dsi->video_mode_format == VIDEO_MODE_BURST) {
 		if (mipi_config->target_burst_mode_freq) {
-			computed_ddr =
-				(pclk * bits_per_pixel) / intel_dsi->lane_count;
+			computed_ddr = (pclk * bpp) / intel_dsi->lane_count;
 
 			if (mipi_config->target_burst_mode_freq <
 								computed_ddr) {
@@ -499,7 +516,7 @@ struct drm_panel *vbt_panel_init(struct intel_dsi *intel_dsi, u16 panel_id)
 	intel_dsi->burst_mode_ratio = burst_mode_ratio;
 	intel_dsi->pclk = pclk;
 
-	bitrate = (pclk * bits_per_pixel) / intel_dsi->lane_count;
+	bitrate = (pclk * bpp) / intel_dsi->lane_count;
 
 	switch (intel_dsi->escape_clk_div) {
 	case 0:

drivers/gpu/drm/i915/intel_dsi_pll.c

@@ -30,27 +30,6 @@
 #include "i915_drv.h"
 #include "intel_dsi.h"
 
-int dsi_pixel_format_bpp(int pixel_format)
-{
-	int bpp;
-
-	switch (pixel_format) {
-	default:
-	case VID_MODE_FORMAT_RGB888:
-	case VID_MODE_FORMAT_RGB666:
-		bpp = 24;
-		break;
-	case VID_MODE_FORMAT_RGB666_PACKED:
-		bpp = 18;
-		break;
-	case VID_MODE_FORMAT_RGB565:
-		bpp = 16;
-		break;
-	}
-
-	return bpp;
-}
-
 struct dsi_mnp {
 	u32 dsi_pll_ctrl;
 	u32 dsi_pll_div;
@@ -64,10 +43,11 @@ static const u32 lfsr_converts[] = {
 };
 
 /* Get DSI clock from pixel clock */
-static u32 dsi_clk_from_pclk(u32 pclk, int pixel_format, int lane_count)
+static u32 dsi_clk_from_pclk(u32 pclk, enum mipi_dsi_pixel_format fmt,
+			     int lane_count)
 {
 	u32 dsi_clk_khz;
-	u32 bpp = dsi_pixel_format_bpp(pixel_format);
+	u32 bpp = mipi_dsi_pixel_format_to_bpp(fmt);
 
 	/* DSI data rate = pixel clock * bits per pixel / lane count
 	   pixel clock is converted from KHz to Hz */
@@ -232,9 +212,9 @@ static void bxt_disable_dsi_pll(struct intel_encoder *encoder)
 		DRM_ERROR("Timeout waiting for PLL lock deassertion\n");
 }
 
-static void assert_bpp_mismatch(int pixel_format, int pipe_bpp)
+static void assert_bpp_mismatch(enum mipi_dsi_pixel_format fmt, int pipe_bpp)
 {
-	int bpp = dsi_pixel_format_bpp(pixel_format);
+	int bpp = mipi_dsi_pixel_format_to_bpp(fmt);
 
 	WARN(bpp != pipe_bpp,
 	     "bpp match assertion failure (expected %d, current %d)\n",