OMAPDSS: add 'has_writeback' flag

At the moment we have a function to get the number of writeback
pipelines supported. However, the function is used in a wrong way,
causing a wrong pipeline to get configured when trying to use WB. Also,
we only have a single writeback pipeline on any of the DSS versions.

To fix and simplify this, create a 'has_writeback' flag into the dispc
driver, and after checking the flag, use OMAP_DSS_WB pipeline
explicitly when calling the configuration functions.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drivers/video/fbdev/omap2/dss/dispc.c

@@ -102,6 +102,8 @@ struct dispc_features {
 
 	/* POL_FREQ has ALIGN bit */
 	bool supports_sync_align:1;
+
+	bool has_writeback:1;
 };
 
 #define DISPC_MAX_NR_FIFOS 5
@@ -710,7 +712,6 @@ static void dispc_setup_color_conv_coef(void)
 {
 	int i;
 	int num_ovl = dss_feat_get_num_ovls();
-	int num_wb = dss_feat_get_num_wbs();
 	const struct color_conv_coef ctbl_bt601_5_ovl = {
 		298, 409, 0, 298, -208, -100, 298, 0, 517, 0,
 	};
@@ -721,8 +722,8 @@ static void dispc_setup_color_conv_coef(void)
 	for (i = 1; i < num_ovl; i++)
 		dispc_ovl_write_color_conv_coef(i, &ctbl_bt601_5_ovl);
 
-	for (; i < num_wb; i++)
+	if (dispc.feat->has_writeback)
-		dispc_ovl_write_color_conv_coef(i, &ctbl_bt601_5_wb);
+		dispc_ovl_write_color_conv_coef(OMAP_DSS_WB, &ctbl_bt601_5_wb);
 }
 
 static void dispc_ovl_set_ba0(enum omap_plane plane, u32 paddr)
@@ -3562,7 +3563,7 @@ static void dispc_dump_regs(struct seq_file *s)
 			DUMPREG(i, DISPC_OVL_ATTRIBUTES2);
 	}
 
-	if (dss_feat_get_num_wbs()) {
+	if (dispc.feat->has_writeback) {
 		i = OMAP_DSS_WB;
 		DUMPREG(i, DISPC_OVL_BA0);
 		DUMPREG(i, DISPC_OVL_BA1);
@@ -3892,6 +3893,7 @@ static const struct dispc_features omap44xx_dispc_feats = {
 	.gfx_fifo_workaround	=	true,
 	.set_max_preload	=	true,
 	.supports_sync_align	=	true,
+	.has_writeback		=	true,
 };
 
 static const struct dispc_features omap54xx_dispc_feats = {
@@ -3914,6 +3916,7 @@ static const struct dispc_features omap54xx_dispc_feats = {
 	.mstandby_workaround	=	true,
 	.set_max_preload	=	true,
 	.supports_sync_align	=	true,
+	.has_writeback		=	true,
 };
 
 static int dispc_init_features(struct platform_device *pdev)

drivers/video/fbdev/omap2/dss/dss_features.c

@@ -46,7 +46,6 @@ struct omap_dss_features {
 
 	const int num_mgrs;
 	const int num_ovls;
-	const int num_wbs;
 	const enum omap_display_type *supported_displays;
 	const enum omap_dss_output_id *supported_outputs;
 	const enum omap_color_mode *supported_color_modes;
@@ -735,7 +734,6 @@ static const struct omap_dss_features omap4430_es1_0_dss_features  = {
 
 	.num_mgrs = 3,
 	.num_ovls = 4,
-	.num_wbs = 1,
 	.supported_displays = omap4_dss_supported_displays,
 	.supported_outputs = omap4_dss_supported_outputs,
 	.supported_color_modes = omap4_dss_supported_color_modes,
@@ -757,7 +755,6 @@ static const struct omap_dss_features omap4430_es2_0_1_2_dss_features = {
 
 	.num_mgrs = 3,
 	.num_ovls = 4,
-	.num_wbs = 1,
 	.supported_displays = omap4_dss_supported_displays,
 	.supported_outputs = omap4_dss_supported_outputs,
 	.supported_color_modes = omap4_dss_supported_color_modes,
@@ -779,7 +776,6 @@ static const struct omap_dss_features omap4_dss_features = {
 
 	.num_mgrs = 3,
 	.num_ovls = 4,
-	.num_wbs = 1,
 	.supported_displays = omap4_dss_supported_displays,
 	.supported_outputs = omap4_dss_supported_outputs,
 	.supported_color_modes = omap4_dss_supported_color_modes,
@@ -801,7 +797,6 @@ static const struct omap_dss_features omap5_dss_features = {
 
 	.num_mgrs = 4,
 	.num_ovls = 4,
-	.num_wbs = 1,
 	.supported_displays = omap5_dss_supported_displays,
 	.supported_outputs = omap5_dss_supported_outputs,
 	.supported_color_modes = omap4_dss_supported_color_modes,
@@ -826,11 +821,6 @@ int dss_feat_get_num_ovls(void)
 }
 EXPORT_SYMBOL(dss_feat_get_num_ovls);
 
-int dss_feat_get_num_wbs(void)
-{
-	return omap_current_dss_features->num_wbs;
-}
-
 unsigned long dss_feat_get_param_min(enum dss_range_param param)
 {
 	return omap_current_dss_features->dss_params[param].min;

drivers/video/fbdev/omap2/dss/dss_features.h

@@ -86,7 +86,6 @@ enum dss_range_param {
 };
 
 /* DSS Feature Functions */
-int dss_feat_get_num_wbs(void);
 unsigned long dss_feat_get_param_min(enum dss_range_param param);
 unsigned long dss_feat_get_param_max(enum dss_range_param param);
 enum omap_overlay_caps dss_feat_get_overlay_caps(enum omap_plane plane);