Merge branch 'archit/wb-dispc-for-3.7'

Merge omapdss writeback work. These patches implement the low level writeback
features in the DISPC, but do not yet add a way to actually use the writeback
from the userspace.

* archit/wb-dispc-for-3.7:
  OMAPDSS: DISPC: Configure color conversion coefficients for writeback
  OMAPDSS: DISPC: Add manager like functions for writeback
  OMAPDSS: DISPC: Configure writeback FIFOs
  OMAPDSS: DISPC: Configure writeback specific parameters in dispc_wb_setup()
  OMAPDSS: DISPC: Configure overlay-like parameters in dispc_wb_setup
  OMAPDSS: DISPC: Add function to set channel in for writeback
  OMAPDSS: DISPC: Don't set chroma resampling bit for writeback
  OMAPDSS: DISPC: Downscale chroma if plane is writeback
  OMAPDSS: DISPC: Configure input and output sizes for writeback
  OMAPDSS: DISPC: Add writeback register offsets and dss features structs
  OMAPDSS: DISPC: Allow both upscaling and downscaling of chroma
  OMAPDSS: DIPSC: Relax scaling limitations when in memory to memory mode
  OMAPDSS: DISPC: Don't pass channel out when configuring overlays
  OMAPDSS: DISPC: Make dispc_ovl_setup call dispc_ovl_setup_common
  OMAPDSS: OVERLAY: Add position and replication as overlay caps
  OMAPDSS: DISPC: Pass overlay caps as a parameter to dispc plane functions
  OMAPDSS: DISPC: Simplify function names for setting pipeline input and output sizes
  OMAPDSS: DISPC: Constify omap_overlay_info in dispc_ovl_setup()

7 files changed, 510 insertions, 185 deletions

diff --git a/drivers/video/omap2/dss/apply.c b/drivers/video/omap2/dss/apply.c
index 2b1fa851a8b..19d66f471b4 100644
--- a/drivers/video/omap2/dss/apply.c
+++ b/drivers/video/omap2/dss/apply.c
@@ -584,7 +584,7 @@ static void dss_ovl_write_regs(struct omap_overlay *ovl)
 
 	replication = dss_ovl_use_replication(mp->lcd_config, oi->color_mode);
 
-	r = dispc_ovl_setup(ovl->id, oi, replication, &mp->timings);
+	r = dispc_ovl_setup(ovl->id, oi, replication, &mp->timings, false);
 	if (r) {
 		/*
 		 * We can't do much here, as this function can be called from
diff --git a/drivers/video/omap2/dss/dispc.c b/drivers/video/omap2/dss/dispc.c
index 811fe381aae..a173a9481a2 100644
--- a/drivers/video/omap2/dss/dispc.c
+++ b/drivers/video/omap2/dss/dispc.c
@@ -86,14 +86,15 @@ struct dispc_features {
 	u16 sw_max;
 	u16 vp_max;
 	u16 hp_max;
-	int (*calc_scaling) (enum omap_channel channel,
+	int (*calc_scaling) (enum omap_plane plane,
 		const struct omap_video_timings *mgr_timings,
 		u16 width, u16 height, u16 out_width, u16 out_height,
 		enum omap_color_mode color_mode, bool *five_taps,
 		int *x_predecim, int *y_predecim, int *decim_x, int *decim_y,
-		u16 pos_x, unsigned long *core_clk);
-	unsigned long (*calc_core_clk) (enum omap_channel channel,
-		u16 width, u16 height, u16 out_width, u16 out_height);
+		u16 pos_x, unsigned long *core_clk, bool mem_to_mem);
+	unsigned long (*calc_core_clk) (enum omap_plane plane,
+		u16 width, u16 height, u16 out_width, u16 out_height,
+		bool mem_to_mem);
 	u8 num_fifos;
 
 	/* swap GFX & WB fifos */
@@ -235,7 +236,14 @@ static const struct {
 	},
 };
 
+struct color_conv_coef {
+	int ry, rcr, rcb, gy, gcr, gcb, by, bcr, bcb;
+	int full_range;
+};
+
 static void _omap_dispc_set_irqs(void);
+static unsigned long dispc_plane_pclk_rate(enum omap_plane plane);
+static unsigned long dispc_plane_lclk_rate(enum omap_plane plane);
 
 static inline void dispc_write_reg(const u16 idx, u32 val)
 {
@@ -533,6 +541,11 @@ u32 dispc_mgr_get_framedone_irq(enum omap_channel channel)
 	return mgr_desc[channel].framedone_irq;
 }
 
+u32 dispc_wb_get_framedone_irq(void)
+{
+	return DISPC_IRQ_FRAMEDONEWB;
+}
+
 bool dispc_mgr_go_busy(enum omap_channel channel)
 {
 	return mgr_fld_read(channel, DISPC_MGR_FLD_GO) == 1;
@@ -560,6 +573,30 @@ void dispc_mgr_go(enum omap_channel channel)
 	mgr_fld_write(channel, DISPC_MGR_FLD_GO, 1);
 }
 
+bool dispc_wb_go_busy(void)
+{
+	return REG_GET(DISPC_CONTROL2, 6, 6) == 1;
+}
+
+void dispc_wb_go(void)
+{
+	enum omap_plane plane = OMAP_DSS_WB;
+	bool enable, go;
+
+	enable = REG_GET(DISPC_OVL_ATTRIBUTES(plane), 0, 0) == 1;
+
+	if (!enable)
+		return;
+
+	go = REG_GET(DISPC_CONTROL2, 6, 6) == 1;
+	if (go) {
+		DSSERR("GO bit not down for WB\n");
+		return;
+	}
+
+	REG_FLD_MOD(DISPC_CONTROL2, 1, 6, 6);
+}
+
 static void dispc_ovl_write_firh_reg(enum omap_plane plane, int reg, u32 value)
 {
 	dispc_write_reg(DISPC_OVL_FIR_COEF_H(plane, reg), value);
@@ -642,41 +679,41 @@ static void dispc_ovl_set_scale_coef(enum omap_plane plane, int fir_hinc,
 	}
 }
 
-static void _dispc_setup_color_conv_coef(void)
-{
-	int i;
-	const struct color_conv_coef {
-		int  ry,  rcr,  rcb,   gy,  gcr,  gcb,   by,  bcr,  bcb;
-		int  full_range;
-	}  ctbl_bt601_5 = {
-		298,  409,    0,  298, -208, -100,  298,    0,  517, 0,
-	};
-
-	const struct color_conv_coef *ct;
 
+static void dispc_ovl_write_color_conv_coef(enum omap_plane plane,
+		const struct color_conv_coef *ct)
+{
 #define CVAL(x, y) (FLD_VAL(x, 26, 16) | FLD_VAL(y, 10, 0))
 
-	ct = &ctbl_bt601_5;
+	dispc_write_reg(DISPC_OVL_CONV_COEF(plane, 0), CVAL(ct->rcr, ct->ry));
+	dispc_write_reg(DISPC_OVL_CONV_COEF(plane, 1), CVAL(ct->gy,  ct->rcb));
+	dispc_write_reg(DISPC_OVL_CONV_COEF(plane, 2), CVAL(ct->gcb, ct->gcr));
+	dispc_write_reg(DISPC_OVL_CONV_COEF(plane, 3), CVAL(ct->bcr, ct->by));
+	dispc_write_reg(DISPC_OVL_CONV_COEF(plane, 4), CVAL(0, ct->bcb));
 
-	for (i = 1; i < dss_feat_get_num_ovls(); i++) {
-		dispc_write_reg(DISPC_OVL_CONV_COEF(i, 0),
-			CVAL(ct->rcr, ct->ry));
-		dispc_write_reg(DISPC_OVL_CONV_COEF(i, 1),
-			CVAL(ct->gy,  ct->rcb));
-		dispc_write_reg(DISPC_OVL_CONV_COEF(i, 2),
-			CVAL(ct->gcb, ct->gcr));
-		dispc_write_reg(DISPC_OVL_CONV_COEF(i, 3),
-			CVAL(ct->bcr, ct->by));
-		dispc_write_reg(DISPC_OVL_CONV_COEF(i, 4),
-			CVAL(0, ct->bcb));
-
-		REG_FLD_MOD(DISPC_OVL_ATTRIBUTES(i), ct->full_range,
-			11, 11);
-	}
+	REG_FLD_MOD(DISPC_OVL_ATTRIBUTES(plane), ct->full_range, 11, 11);
 
 #undef CVAL
 }
 
+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,
+	};
+	const struct color_conv_coef ctbl_bt601_5_wb = {
+		66, 112, -38, 129, -94, -74, 25, -18, 112, 0,
+	};
+
+	for (i = 1; i < num_ovl; i++)
+		dispc_ovl_write_color_conv_coef(i, &ctbl_bt601_5_ovl);
+
+	for (; i < num_wb; i++)
+		dispc_ovl_write_color_conv_coef(i, &ctbl_bt601_5_wb);
+}
 
 static void dispc_ovl_set_ba0(enum omap_plane plane, u32 paddr)
 {
@@ -698,24 +735,32 @@ static void dispc_ovl_set_ba1_uv(enum omap_plane plane, u32 paddr)
 	dispc_write_reg(DISPC_OVL_BA1_UV(plane), paddr);
 }
 
-static void dispc_ovl_set_pos(enum omap_plane plane, int x, int y)
+static void dispc_ovl_set_pos(enum omap_plane plane,
+		enum omap_overlay_caps caps, int x, int y)
 {
-	u32 val = FLD_VAL(y, 26, 16) | FLD_VAL(x, 10, 0);
+	u32 val;
+
+	if ((caps & OMAP_DSS_OVL_CAP_POS) == 0)
+		return;
+
+	val = FLD_VAL(y, 26, 16) | FLD_VAL(x, 10, 0);
 
 	dispc_write_reg(DISPC_OVL_POSITION(plane), val);
 }
 
-static void dispc_ovl_set_pic_size(enum omap_plane plane, int width, int height)
+static void dispc_ovl_set_input_size(enum omap_plane plane, int width,
+		int height)
 {
 	u32 val = FLD_VAL(height - 1, 26, 16) | FLD_VAL(width - 1, 10, 0);
 
-	if (plane == OMAP_DSS_GFX)
+	if (plane == OMAP_DSS_GFX || plane == OMAP_DSS_WB)
 		dispc_write_reg(DISPC_OVL_SIZE(plane), val);
 	else
 		dispc_write_reg(DISPC_OVL_PICTURE_SIZE(plane), val);
 }
 
-static void dispc_ovl_set_vid_size(enum omap_plane plane, int width, int height)
+static void dispc_ovl_set_output_size(enum omap_plane plane, int width,
+		int height)
 {
 	u32 val;
 
@@ -723,14 +768,16 @@ static void dispc_ovl_set_vid_size(enum omap_plane plane, int width, int height)
 
 	val = FLD_VAL(height - 1, 26, 16) | FLD_VAL(width - 1, 10, 0);
 
-	dispc_write_reg(DISPC_OVL_SIZE(plane), val);
+	if (plane == OMAP_DSS_WB)
+		dispc_write_reg(DISPC_OVL_PICTURE_SIZE(plane), val);
+	else
+		dispc_write_reg(DISPC_OVL_SIZE(plane), val);
 }
 
-static void dispc_ovl_set_zorder(enum omap_plane plane, u8 zorder)
+static void dispc_ovl_set_zorder(enum omap_plane plane,
+		enum omap_overlay_caps caps, u8 zorder)
 {
-	struct omap_overlay *ovl = omap_dss_get_overlay(plane);
-
-	if ((ovl->caps & OMAP_DSS_OVL_CAP_ZORDER) == 0)
+	if ((caps & OMAP_DSS_OVL_CAP_ZORDER) == 0)
 		return;
 
 	REG_FLD_MOD(DISPC_OVL_ATTRIBUTES(plane), zorder, 27, 26);
@@ -747,23 +794,22 @@ static void dispc_ovl_enable_zorder_planes(void)
 		REG_FLD_MOD(DISPC_OVL_ATTRIBUTES(i), 1, 25, 25);
 }
 
-static void dispc_ovl_set_pre_mult_alpha(enum omap_plane plane, bool enable)
+static void dispc_ovl_set_pre_mult_alpha(enum omap_plane plane,
+		enum omap_overlay_caps caps, bool enable)
 {
-	struct omap_overlay *ovl = omap_dss_get_overlay(plane);
-
-	if ((ovl->caps & OMAP_DSS_OVL_CAP_PRE_MULT_ALPHA) == 0)
+	if ((caps & OMAP_DSS_OVL_CAP_PRE_MULT_ALPHA) == 0)
 		return;
 
 	REG_FLD_MOD(DISPC_OVL_ATTRIBUTES(plane), enable ? 1 : 0, 28, 28);
 }
 
-static void dispc_ovl_setup_global_alpha(enum omap_plane plane, u8 global_alpha)
+static void dispc_ovl_setup_global_alpha(enum omap_plane plane,
+		enum omap_overlay_caps caps, u8 global_alpha)
 {
 	static const unsigned shifts[] = { 0, 8, 16, 24, };
 	int shift;
-	struct omap_overlay *ovl = omap_dss_get_overlay(plane);
 
-	if ((ovl->caps & OMAP_DSS_OVL_CAP_GLOBAL_ALPHA) == 0)
+	if ((caps & OMAP_DSS_OVL_CAP_GLOBAL_ALPHA) == 0)
 		return;
 
 	shift = shifts[plane];
@@ -971,10 +1017,17 @@ static enum omap_channel dispc_ovl_get_channel_out(enum omap_plane plane)
 	return channel;
 }
 
+void dispc_wb_set_channel_in(enum dss_writeback_channel channel)
+{
+	enum omap_plane plane = OMAP_DSS_WB;
+
+	REG_FLD_MOD(DISPC_OVL_ATTRIBUTES(plane), channel, 18, 16);
+}
+
 static void dispc_ovl_set_burst_size(enum omap_plane plane,
 		enum omap_burst_size burst_size)
 {
-	static const unsigned shifts[] = { 6, 14, 14, 14, };
+	static const unsigned shifts[] = { 6, 14, 14, 14, 14, };
 	int shift;
 
 	shift = shifts[plane];
@@ -1051,11 +1104,15 @@ static void dispc_ovl_set_vid_color_conv(enum omap_plane plane, bool enable)
 	dispc_write_reg(DISPC_OVL_ATTRIBUTES(plane), val);
 }
 
-static void dispc_ovl_enable_replication(enum omap_plane plane, bool enable)
+static void dispc_ovl_enable_replication(enum omap_plane plane,
+		enum omap_overlay_caps caps, bool enable)
 {
 	static const unsigned shifts[] = { 5, 10, 10, 10 };
 	int shift;
 
+	if ((caps & OMAP_DSS_OVL_CAP_REPLICATION) == 0)
+		return;
+
 	shift = shifts[plane];
 	REG_FLD_MOD(DISPC_OVL_ATTRIBUTES(plane), enable, shift, shift);
 }
@@ -1202,6 +1259,14 @@ void dispc_ovl_compute_fifo_thresholds(enum omap_plane plane,
 	if (manual_update && dss_has_feature(FEAT_OMAP3_DSI_FIFO_BUG)) {
 		*fifo_low = ovl_fifo_size - burst_size * 2;
 		*fifo_high = total_fifo_size - burst_size;
+	} else if (plane == OMAP_DSS_WB) {
+		/*
+		 * Most optimal configuration for writeback is to push out data
+		 * to the interconnect the moment writeback pushes enough pixels
+		 * in the FIFO to form a burst
+		 */
+		*fifo_low = 0;
+		*fifo_high = burst_size;
 	} else {
 		*fifo_low = ovl_fifo_size - burst_size;
 		*fifo_high = total_fifo_size - buf_unit;
@@ -1444,6 +1509,7 @@ static void dispc_ovl_set_scaling_uv(enum omap_plane plane,
 {
 	int scale_x = out_width != orig_width;
 	int scale_y = out_height != orig_height;
+	bool chroma_upscale = plane != OMAP_DSS_WB ? true : false;
 
 	if (!dss_has_feature(FEAT_HANDLE_UV_SEPARATE))
 		return;
@@ -1451,7 +1517,8 @@ static void dispc_ovl_set_scaling_uv(enum omap_plane plane,
 			color_mode != OMAP_DSS_COLOR_UYVY &&
 			color_mode != OMAP_DSS_COLOR_NV12)) {
 		/* reset chroma resampling for RGB formats  */
-		REG_FLD_MOD(DISPC_OVL_ATTRIBUTES2(plane), 0, 8, 8);
+		if (plane != OMAP_DSS_WB)
+			REG_FLD_MOD(DISPC_OVL_ATTRIBUTES2(plane), 0, 8, 8);
 		return;
 	}
 
@@ -1460,23 +1527,34 @@ static void dispc_ovl_set_scaling_uv(enum omap_plane plane,
 
 	switch (color_mode) {
 	case OMAP_DSS_COLOR_NV12:
-		/* UV is subsampled by 2 vertically*/
-		orig_height >>= 1;
-		/* UV is subsampled by 2 horz.*/
-		orig_width >>= 1;
+		if (chroma_upscale) {
+			/* UV is subsampled by 2 horizontally and vertically */
+			orig_height >>= 1;
+			orig_width >>= 1;
+		} else {
+			/* UV is downsampled by 2 horizontally and vertically */
+			orig_height <<= 1;
+			orig_width <<= 1;
+		}
+
 		break;
 	case OMAP_DSS_COLOR_YUV2:
 	case OMAP_DSS_COLOR_UYVY:
-		/*For YUV422 with 90/270 rotation,
-		 *we don't upsample chroma
-		 */
+		/* For YUV422 with 90/270 rotation, we don't upsample chroma */
 		if (rotation == OMAP_DSS_ROT_0 ||
-			rotation == OMAP_DSS_ROT_180)
-			/* UV is subsampled by 2 hrz*/
-			orig_width >>= 1;
+				rotation == OMAP_DSS_ROT_180) {
+			if (chroma_upscale)
+				/* UV is subsampled by 2 horizontally */
+				orig_width >>= 1;
+			else
+				/* UV is downsampled by 2 horizontally */
+				orig_width <<= 1;
+		}
+
 		/* must use FIR for YUV422 if rotated */
 		if (rotation != OMAP_DSS_ROT_0)
 			scale_x = scale_y = true;
+
 		break;
 	default:
 		BUG();
@@ -1492,8 +1570,10 @@ static void dispc_ovl_set_scaling_uv(enum omap_plane plane,
 			out_width, out_height, five_taps,
 				rotation, DISPC_COLOR_COMPONENT_UV);
 
-	REG_FLD_MOD(DISPC_OVL_ATTRIBUTES2(plane),
-		(scale_x || scale_y) ? 1 : 0, 8, 8);
+	if (plane != OMAP_DSS_WB)
+		REG_FLD_MOD(DISPC_OVL_ATTRIBUTES2(plane),
+			(scale_x || scale_y) ? 1 : 0, 8, 8);
+
 	/* set H scaling */
 	REG_FLD_MOD(DISPC_OVL_ATTRIBUTES(plane), scale_x ? 1 : 0, 5, 5);
 	/* set V scaling */
@@ -1909,22 +1989,19 @@ static void calc_tiler_rotation_offset(u16 screen_width, u16 width,
  * This function is used to avoid synclosts in OMAP3, because of some
  * undocumented horizontal position and timing related limitations.
  */
-static int check_horiz_timing_omap3(enum omap_channel channel,
+static int check_horiz_timing_omap3(enum omap_plane plane,
 		const struct omap_video_timings *t, u16 pos_x,
 		u16 width, u16 height, u16 out_width, u16 out_height)
 {
 	int DS = DIV_ROUND_UP(height, out_height);
-	unsigned long nonactive, lclk, pclk;
+	unsigned long nonactive;
 	static const u8 limits[3] = { 8, 10, 20 };
 	u64 val, blank;
+	unsigned long pclk = dispc_plane_pclk_rate(plane);
+	unsigned long lclk = dispc_plane_lclk_rate(plane);
 	int i;
 
 	nonactive = t->x_res + t->hfp + t->hsw + t->hbp - out_width;
-	pclk = dispc_mgr_pclk_rate(channel);
-	if (dss_mgr_is_lcd(channel))
-		lclk = dispc_mgr_lclk_rate(channel);
-	else
-		lclk = dispc_fclk_rate();
 
 	i = 0;
 	if (out_height < height)
@@ -1961,13 +2038,14 @@ static int check_horiz_timing_omap3(enum omap_channel channel,
 	return 0;
 }
 
-static unsigned long calc_core_clk_five_taps(enum omap_channel channel,
+static unsigned long calc_core_clk_five_taps(enum omap_plane plane,
 		const struct omap_video_timings *mgr_timings, u16 width,
 		u16 height, u16 out_width, u16 out_height,
 		enum omap_color_mode color_mode)
 {
 	u32 core_clk = 0;
-	u64 tmp, pclk = dispc_mgr_pclk_rate(channel);
+	u64 tmp;
+	unsigned long pclk = dispc_plane_pclk_rate(plane);
 
 	if (height <= out_height && width <= out_width)
 		return (unsigned long) pclk;
@@ -2001,10 +2079,10 @@ static unsigned long calc_core_clk_five_taps(enum omap_channel channel,
 	return core_clk;
 }
 
-static unsigned long calc_core_clk_24xx(enum omap_channel channel, u16 width,
-		u16 height, u16 out_width, u16 out_height)
+static unsigned long calc_core_clk_24xx(enum omap_plane plane, u16 width,
+		u16 height, u16 out_width, u16 out_height, bool mem_to_mem)
 {
-	unsigned long pclk = dispc_mgr_pclk_rate(channel);
+	unsigned long pclk = dispc_plane_pclk_rate(plane);
 
 	if (height > out_height && width > out_width)
 		return pclk * 4;
@@ -2012,11 +2090,11 @@ static unsigned long calc_core_clk_24xx(enum omap_channel channel, u16 width,
 		return pclk * 2;
 }
 
-static unsigned long calc_core_clk_34xx(enum omap_channel channel, u16 width,
-		u16 height, u16 out_width, u16 out_height)
+static unsigned long calc_core_clk_34xx(enum omap_plane plane, u16 width,
+		u16 height, u16 out_width, u16 out_height, bool mem_to_mem)
 {
 	unsigned int hf, vf;
-	unsigned long pclk = dispc_mgr_pclk_rate(channel);
+	unsigned long pclk = dispc_plane_pclk_rate(plane);
 
 	/*
 	 * FIXME how to determine the 'A' factor
@@ -2039,10 +2117,21 @@ static unsigned long calc_core_clk_34xx(enum omap_channel channel, u16 width,
 	return pclk * vf * hf;
 }
 
-static unsigned long calc_core_clk_44xx(enum omap_channel channel, u16 width,
-		u16 height, u16 out_width, u16 out_height)
+static unsigned long calc_core_clk_44xx(enum omap_plane plane, u16 width,
+		u16 height, u16 out_width, u16 out_height, bool mem_to_mem)
 {
-	unsigned long pclk = dispc_mgr_pclk_rate(channel);
+	unsigned long pclk;
+
+	/*
+	 * If the overlay/writeback is in mem to mem mode, there are no
+	 * downscaling limitations with respect to pixel clock, return 1 as
+	 * required core clock to represent that we have sufficient enough
+	 * core clock to do maximum downscaling
+	 */
+	if (mem_to_mem)
+		return 1;
+
+	pclk = dispc_plane_pclk_rate(plane);
 
 	if (width > out_width)
 		return DIV_ROUND_UP(pclk, out_width) * width;
@@ -2050,25 +2139,26 @@ static unsigned long calc_core_clk_44xx(enum omap_channel channel, u16 width,
 		return pclk;
 }
 
-static int dispc_ovl_calc_scaling_24xx(enum omap_channel channel,
+static int dispc_ovl_calc_scaling_24xx(enum omap_plane plane,
 		const struct omap_video_timings *mgr_timings,
 		u16 width, u16 height, u16 out_width, u16 out_height,
 		enum omap_color_mode color_mode, bool *five_taps,
 		int *x_predecim, int *y_predecim, int *decim_x, int *decim_y,
-		u16 pos_x, unsigned long *core_clk)
+		u16 pos_x, unsigned long *core_clk, bool mem_to_mem)
 {
 	int error;
 	u16 in_width, in_height;
 	int min_factor = min(*decim_x, *decim_y);
 	const int maxsinglelinewidth =
 			dss_feat_get_param_max(FEAT_PARAM_LINEWIDTH);
+
 	*five_taps = false;
 
 	do {
 		in_height = DIV_ROUND_UP(height, *decim_y);
 		in_width = DIV_ROUND_UP(width, *decim_x);
-		*core_clk = dispc.feat->calc_core_clk(channel, in_width,
-				in_height, out_width, out_height);
+		*core_clk = dispc.feat->calc_core_clk(plane, in_width,
+				in_height, out_width, out_height, mem_to_mem);
 		error = (in_width > maxsinglelinewidth || !*core_clk ||
 			*core_clk > dispc_core_clk_rate());
 		if (error) {
@@ -2090,12 +2180,12 @@ static int dispc_ovl_calc_scaling_24xx(enum omap_channel channel,
 	return 0;
 }
 
-static int dispc_ovl_calc_scaling_34xx(enum omap_channel channel,
+static int dispc_ovl_calc_scaling_34xx(enum omap_plane plane,
 		const struct omap_video_timings *mgr_timings,
 		u16 width, u16 height, u16 out_width, u16 out_height,
 		enum omap_color_mode color_mode, bool *five_taps,
 		int *x_predecim, int *y_predecim, int *decim_x, int *decim_y,
-		u16 pos_x, unsigned long *core_clk)
+		u16 pos_x, unsigned long *core_clk, bool mem_to_mem)
 {
 	int error;
 	u16 in_width, in_height;
@@ -2106,19 +2196,21 @@ static int dispc_ovl_calc_scaling_34xx(enum omap_channel channel,
 	do {
 		in_height = DIV_ROUND_UP(height, *decim_y);
 		in_width = DIV_ROUND_UP(width, *decim_x);
-		*core_clk = calc_core_clk_five_taps(channel, mgr_timings,
+		*core_clk = calc_core_clk_five_taps(plane, mgr_timings,
 			in_width, in_height, out_width, out_height, color_mode);
 
-		error = check_horiz_timing_omap3(channel, mgr_timings, pos_x,
-			in_width, in_height, out_width, out_height);
+		error = check_horiz_timing_omap3(plane, mgr_timings,
+				pos_x, in_width, in_height, out_width,
+				out_height);
 
 		if (in_width > maxsinglelinewidth)
 			if (in_height > out_height &&
 						in_height < out_height * 2)
 				*five_taps = false;
 		if (!*five_taps)
-			*core_clk = dispc.feat->calc_core_clk(channel, in_width,
-					in_height, out_width, out_height);
+			*core_clk = dispc.feat->calc_core_clk(plane, in_width,
+					in_height, out_width, out_height,
+					mem_to_mem);
 
 		error = (error || in_width > maxsinglelinewidth * 2 ||
 			(in_width > maxsinglelinewidth && *five_taps) ||
@@ -2135,7 +2227,7 @@ static int dispc_ovl_calc_scaling_34xx(enum omap_channel channel,
 		}
 	} while (*decim_x <= *x_predecim && *decim_y <= *y_predecim && error);
 
-	if (check_horiz_timing_omap3(channel, mgr_timings, pos_x, width, height,
+	if (check_horiz_timing_omap3(plane, mgr_timings, pos_x, width, height,
 		out_width, out_height)){
 			DSSERR("horizontal timing too tight\n");
 			return -EINVAL;
@@ -2154,21 +2246,27 @@ static int dispc_ovl_calc_scaling_34xx(enum omap_channel channel,
 	return 0;
 }
 
-static int dispc_ovl_calc_scaling_44xx(enum omap_channel channel,
+static int dispc_ovl_calc_scaling_44xx(enum omap_plane plane,
 		const struct omap_video_timings *mgr_timings,
 		u16 width, u16 height, u16 out_width, u16 out_height,
 		enum omap_color_mode color_mode, bool *five_taps,
 		int *x_predecim, int *y_predecim, int *decim_x, int *decim_y,
-		u16 pos_x, unsigned long *core_clk)
+		u16 pos_x, unsigned long *core_clk, bool mem_to_mem)
 {
 	u16 in_width, in_width_max;
 	int decim_x_min = *decim_x;
 	u16 in_height = DIV_ROUND_UP(height, *decim_y);
 	const int maxsinglelinewidth =
 				dss_feat_get_param_max(FEAT_PARAM_LINEWIDTH);
+	unsigned long pclk = dispc_plane_pclk_rate(plane);
+	const int maxdownscale = dss_feat_get_param_max(FEAT_PARAM_DOWNSCALE);
+
+	if (mem_to_mem)
+		in_width_max = DIV_ROUND_UP(out_width, maxdownscale);
+	else
+		in_width_max = dispc_core_clk_rate() /
+					DIV_ROUND_UP(pclk, out_width);
 
-	in_width_max = dispc_core_clk_rate() /
-			DIV_ROUND_UP(dispc_mgr_pclk_rate(channel), out_width);
 	*decim_x = DIV_ROUND_UP(width, in_width_max);
 
 	*decim_x = *decim_x > decim_x_min ? *decim_x : decim_x_min;
@@ -2185,20 +2283,19 @@ static int dispc_ovl_calc_scaling_44xx(enum omap_channel channel,
 		return -EINVAL;
 	}
 
-	*core_clk = dispc.feat->calc_core_clk(channel, in_width, in_height,
-				out_width, out_height);
+	*core_clk = dispc.feat->calc_core_clk(plane, in_width, in_height,
+				out_width, out_height, mem_to_mem);
 	return 0;
 }
 
 static int dispc_ovl_calc_scaling(enum omap_plane plane,
-		enum omap_channel channel,
+		enum omap_overlay_caps caps,
 		const struct omap_video_timings *mgr_timings,
 		u16 width, u16 height, u16 out_width, u16 out_height,
 		enum omap_color_mode color_mode, bool *five_taps,
 		int *x_predecim, int *y_predecim, u16 pos_x,
-		enum omap_dss_rotation_type rotation_type)
+		enum omap_dss_rotation_type rotation_type, bool mem_to_mem)
 {
-	struct omap_overlay *ovl = omap_dss_get_overlay(plane);
 	const int maxdownscale = dss_feat_get_param_max(FEAT_PARAM_DOWNSCALE);
 	const int max_decim_limit = 16;
 	unsigned long core_clk = 0;
@@ -2207,7 +2304,7 @@ static int dispc_ovl_calc_scaling(enum omap_plane plane,
 	if (width == out_width && height == out_height)
 		return 0;
 
-	if ((ovl->caps & OMAP_DSS_OVL_CAP_SCALE) == 0)
+	if ((caps & OMAP_DSS_OVL_CAP_SCALE) == 0)
 		return -EINVAL;
 
 	*x_predecim = max_decim_limit;
@@ -2233,9 +2330,10 @@ static int dispc_ovl_calc_scaling(enum omap_plane plane,
 	if (decim_y > *y_predecim || out_height > height * 8)
 		return -EINVAL;
 
-	ret = dispc.feat->calc_scaling(channel, mgr_timings, width, height,
-		out_width, out_height, color_mode, five_taps, x_predecim,
-		y_predecim, &decim_x, &decim_y, pos_x, &core_clk);
+	ret = dispc.feat->calc_scaling(plane, mgr_timings, width, height,
+		out_width, out_height, color_mode, five_taps,
+		x_predecim, y_predecim, &decim_x, &decim_y, pos_x, &core_clk,
+		mem_to_mem);
 	if (ret)
 		return ret;
 
@@ -2255,70 +2353,64 @@ static int dispc_ovl_calc_scaling(enum omap_plane plane,
 	return 0;
 }
 
-int dispc_ovl_setup(enum omap_plane plane, struct omap_overlay_info *oi,
-		bool replication, const struct omap_video_timings *mgr_timings)
+static int dispc_ovl_setup_common(enum omap_plane plane,
+		enum omap_overlay_caps caps, u32 paddr, u32 p_uv_addr,
+		u16 screen_width, int pos_x, int pos_y, u16 width, u16 height,
+		u16 out_width, u16 out_height, enum omap_color_mode color_mode,
+		u8 rotation, bool mirror, u8 zorder, u8 pre_mult_alpha,
+		u8 global_alpha, enum omap_dss_rotation_type rotation_type,
+		bool replication, const struct omap_video_timings *mgr_timings,
+		bool mem_to_mem)
 {
-	struct omap_overlay *ovl = omap_dss_get_overlay(plane);
 	bool five_taps = true;
 	bool fieldmode = 0;
 	int r, cconv = 0;
 	unsigned offset0, offset1;
 	s32 row_inc;
 	s32 pix_inc;
-	u16 frame_height = oi->height;
+	u16 frame_height = height;
 	unsigned int field_offset = 0;
-	u16 in_height = oi->height;
-	u16 in_width = oi->width;
-	u16 out_width, out_height;
-	enum omap_channel channel;
+	u16 in_height = height;
+	u16 in_width = width;
 	int x_predecim = 1, y_predecim = 1;
 	bool ilace = mgr_timings->interlace;
 
-	channel = dispc_ovl_get_channel_out(plane);
-
-	DSSDBG("dispc_ovl_setup %d, pa %x, pa_uv %x, sw %d, %d,%d, %dx%d -> "
-		"%dx%d, cmode %x, rot %d, mir %d, ilace %d chan %d repl %d\n",
-		plane, oi->paddr, oi->p_uv_addr,
-		oi->screen_width, oi->pos_x, oi->pos_y, oi->width, oi->height,
-		oi->out_width, oi->out_height, oi->color_mode, oi->rotation,
-		oi->mirror, ilace, channel, replication);
-
-	if (oi->paddr == 0)
+	if (paddr == 0)
 		return -EINVAL;
 
-	out_width = oi->out_width == 0 ? oi->width : oi->out_width;
-	out_height = oi->out_height == 0 ? oi->height : oi->out_height;
+	out_width = out_width == 0 ? width : out_width;
+	out_height = out_height == 0 ? height : out_height;
 
-	if (ilace && oi->height == out_height)
+	if (ilace && height == out_height)
 		fieldmode = 1;
 
 	if (ilace) {
 		if (fieldmode)
 			in_height /= 2;
-		oi->pos_y /= 2;
+		pos_y /= 2;
 		out_height /= 2;
 
 		DSSDBG("adjusting for ilace: height %d, pos_y %d, "
-				"out_height %d\n",
-				in_height, oi->pos_y, out_height);
+			"out_height %d\n", in_height, pos_y,
+			out_height);
 	}
 
-	if (!dss_feat_color_mode_supported(plane, oi->color_mode))
+	if (!dss_feat_color_mode_supported(plane, color_mode))
 		return -EINVAL;
 
-	r = dispc_ovl_calc_scaling(plane, channel, mgr_timings, in_width,
-			in_height, out_width, out_height, oi->color_mode,
-			&five_taps, &x_predecim, &y_predecim, oi->pos_x,
-			oi->rotation_type);
+	r = dispc_ovl_calc_scaling(plane, caps, mgr_timings, in_width,
+			in_height, out_width, out_height, color_mode,
+			&five_taps, &x_predecim, &y_predecim, pos_x,
+			rotation_type, mem_to_mem);
 	if (r)
 		return r;
 
 	in_width = DIV_ROUND_UP(in_width, x_predecim);
 	in_height = DIV_ROUND_UP(in_height, y_predecim);
 
-	if (oi->color_mode == OMAP_DSS_COLOR_YUV2 ||
-			oi->color_mode == OMAP_DSS_COLOR_UYVY ||
-			oi->color_mode == OMAP_DSS_COLOR_NV12)
+	if (color_mode == OMAP_DSS_COLOR_YUV2 ||
+			color_mode == OMAP_DSS_COLOR_UYVY ||
+			color_mode == OMAP_DSS_COLOR_NV12)
 		cconv = 1;
 
 	if (ilace && !fieldmode) {
@@ -2344,70 +2436,144 @@ int dispc_ovl_setup(enum omap_plane plane, struct omap_overlay_info *oi,
 	row_inc = 0;
 	pix_inc = 0;
 
-	if (oi->rotation_type == OMAP_DSS_ROT_TILER)
-		calc_tiler_rotation_offset(oi->screen_width, in_width,
-				oi->color_mode, fieldmode, field_offset,
+	if (rotation_type == OMAP_DSS_ROT_TILER)
+		calc_tiler_rotation_offset(screen_width, in_width,
+				color_mode, fieldmode, field_offset,
 				&offset0, &offset1, &row_inc, &pix_inc,
 				x_predecim, y_predecim);
-	else if (oi->rotation_type == OMAP_DSS_ROT_DMA)
-		calc_dma_rotation_offset(oi->rotation, oi->mirror,
-				oi->screen_width, in_width, frame_height,
-				oi->color_mode, fieldmode, field_offset,
+	else if (rotation_type == OMAP_DSS_ROT_DMA)
+		calc_dma_rotation_offset(rotation, mirror,
+				screen_width, in_width, frame_height,
+				color_mode, fieldmode, field_offset,
 				&offset0, &offset1, &row_inc, &pix_inc,
 				x_predecim, y_predecim);
 	else
-		calc_vrfb_rotation_offset(oi->rotation, oi->mirror,
-				oi->screen_width, in_width, frame_height,
-				oi->color_mode, fieldmode, field_offset,
+		calc_vrfb_rotation_offset(rotation, mirror,
+				screen_width, in_width, frame_height,
+				color_mode, fieldmode, field_offset,
 				&offset0, &offset1, &row_inc, &pix_inc,
 				x_predecim, y_predecim);
 
 	DSSDBG("offset0 %u, offset1 %u, row_inc %d, pix_inc %d\n",
 			offset0, offset1, row_inc, pix_inc);
 
-	dispc_ovl_set_color_mode(plane, oi->color_mode);
+	dispc_ovl_set_color_mode(plane, color_mode);
 
-	dispc_ovl_configure_burst_type(plane, oi->rotation_type);
+	dispc_ovl_configure_burst_type(plane, rotation_type);
 
-	dispc_ovl_set_ba0(plane, oi->paddr + offset0);
-	dispc_ovl_set_ba1(plane, oi->paddr + offset1);
+	dispc_ovl_set_ba0(plane, paddr + offset0);
+	dispc_ovl_set_ba1(plane, paddr + offset1);
 
-	if (OMAP_DSS_COLOR_NV12 == oi->color_mode) {
-		dispc_ovl_set_ba0_uv(plane, oi->p_uv_addr + offset0);
-		dispc_ovl_set_ba1_uv(plane, oi->p_uv_addr + offset1);
+	if (OMAP_DSS_COLOR_NV12 == color_mode) {
+		dispc_ovl_set_ba0_uv(plane, p_uv_addr + offset0);
+		dispc_ovl_set_ba1_uv(plane, p_uv_addr + offset1);
 	}
 
-
 	dispc_ovl_set_row_inc(plane, row_inc);
 	dispc_ovl_set_pix_inc(plane, pix_inc);
 
-	DSSDBG("%d,%d %dx%d -> %dx%d\n", oi->pos_x, oi->pos_y, in_width,
+	DSSDBG("%d,%d %dx%d -> %dx%d\n", pos_x, pos_y, in_width,
 			in_height, out_width, out_height);
 
-	dispc_ovl_set_pos(plane, oi->pos_x, oi->pos_y);
+	dispc_ovl_set_pos(plane, caps, pos_x, pos_y);
 
-	dispc_ovl_set_pic_size(plane, in_width, in_height);
+	dispc_ovl_set_input_size(plane, in_width, in_height);
 
-	if (ovl->caps & OMAP_DSS_OVL_CAP_SCALE) {
+	if (caps & OMAP_DSS_OVL_CAP_SCALE) {
 		dispc_ovl_set_scaling(plane, in_width, in_height, out_width,
 				   out_height, ilace, five_taps, fieldmode,
-				   oi->color_mode, oi->rotation);
-		dispc_ovl_set_vid_size(plane, out_width, out_height);
+				   color_mode, rotation);
+		dispc_ovl_set_output_size(plane, out_width, out_height);
 		dispc_ovl_set_vid_color_conv(plane, cconv);
 	}
 
-	dispc_ovl_set_rotation_attrs(plane, oi->rotation, oi->mirror,
-			oi->color_mode);
+	dispc_ovl_set_rotation_attrs(plane, rotation, mirror, color_mode);
 
-	dispc_ovl_set_zorder(plane, oi->zorder);
-	dispc_ovl_set_pre_mult_alpha(plane, oi->pre_mult_alpha);
-	dispc_ovl_setup_global_alpha(plane, oi->global_alpha);
+	dispc_ovl_set_zorder(plane, caps, zorder);
+	dispc_ovl_set_pre_mult_alpha(plane, caps, pre_mult_alpha);
+	dispc_ovl_setup_global_alpha(plane, caps, global_alpha);
 
-	dispc_ovl_enable_replication(plane, replication);
+	dispc_ovl_enable_replication(plane, caps, replication);
 
 	return 0;
 }
 
+int dispc_ovl_setup(enum omap_plane plane, const struct omap_overlay_info *oi,
+		bool replication, const struct omap_video_timings *mgr_timings,
+		bool mem_to_mem)
+{
+	int r;
+	struct omap_overlay *ovl = omap_dss_get_overlay(plane);
+	enum omap_channel channel;
+
+	channel = dispc_ovl_get_channel_out(plane);
+
+	DSSDBG("dispc_ovl_setup %d, pa %x, pa_uv %x, sw %d, %d,%d, %dx%d -> "
+		"%dx%d, cmode %x, rot %d, mir %d, chan %d repl %d\n",
+		plane, oi->paddr, oi->p_uv_addr, oi->screen_width, oi->pos_x,
+		oi->pos_y, oi->width, oi->height, oi->out_width, oi->out_height,
+		oi->color_mode, oi->rotation, oi->mirror, channel, replication);
+
+	r = dispc_ovl_setup_common(plane, ovl->caps, oi->paddr, oi->p_uv_addr,
+		oi->screen_width, oi->pos_x, oi->pos_y, oi->width, oi->height,
+		oi->out_width, oi->out_height, oi->color_mode, oi->rotation,
+		oi->mirror, oi->zorder, oi->pre_mult_alpha, oi->global_alpha,
+		oi->rotation_type, replication, mgr_timings, mem_to_mem);
+
+	return r;
+}
+
+int dispc_wb_setup(const struct omap_dss_writeback_info *wi,
+		bool mem_to_mem, const struct omap_video_timings *mgr_timings)
+{
+	int r;
+	u32 l;
+	enum omap_plane plane = OMAP_DSS_WB;
+	const int pos_x = 0, pos_y = 0;
+	const u8 zorder = 0, global_alpha = 0;
+	const bool replication = false;
+	bool truncation;
+	int in_width = mgr_timings->x_res;
+	int in_height = mgr_timings->y_res;
+	enum omap_overlay_caps caps =
+		OMAP_DSS_OVL_CAP_SCALE | OMAP_DSS_OVL_CAP_PRE_MULT_ALPHA;
+
+	DSSDBG("dispc_wb_setup, pa %x, pa_uv %x, %d,%d -> %dx%d, cmode %x, "
+		"rot %d, mir %d\n", wi->paddr, wi->p_uv_addr, in_width,
+		in_height, wi->width, wi->height, wi->color_mode, wi->rotation,
+		wi->mirror);
+
+	r = dispc_ovl_setup_common(plane, caps, wi->paddr, wi->p_uv_addr,
+		wi->buf_width, pos_x, pos_y, in_width, in_height, wi->width,
+		wi->height, wi->color_mode, wi->rotation, wi->mirror, zorder,
+		wi->pre_mult_alpha, global_alpha, wi->rotation_type,
+		replication, mgr_timings, mem_to_mem);
+
+	switch (wi->color_mode) {
+	case OMAP_DSS_COLOR_RGB16:
+	case OMAP_DSS_COLOR_RGB24P:
+	case OMAP_DSS_COLOR_ARGB16:
+	case OMAP_DSS_COLOR_RGBA16:
+	case OMAP_DSS_COLOR_RGB12U:
+	case OMAP_DSS_COLOR_ARGB16_1555:
+	case OMAP_DSS_COLOR_XRGB16_1555:
+	case OMAP_DSS_COLOR_RGBX16:
+		truncation = true;
+		break;
+	default:
+		truncation = false;
+		break;
+	}
+
+	/* setup extra DISPC_WB_ATTRIBUTES */
+	l = dispc_read_reg(DISPC_OVL_ATTRIBUTES(plane));
+	l = FLD_MOD(l, truncation, 10, 10);	/* TRUNCATIONENABLE */
+	l = FLD_MOD(l, mem_to_mem, 19, 19);	/* WRITEBACKMODE */
+	dispc_write_reg(DISPC_OVL_ATTRIBUTES(plane), l);
+
+	return r;
+}
+
 int dispc_ovl_enable(enum omap_plane plane, bool enable)
 {
 	DSSDBG("dispc_enable_plane %d, %d\n", plane, enable);
@@ -2560,6 +2726,47 @@ void dispc_mgr_enable(enum omap_channel channel, bool enable)
 		BUG();
 }
 
+void dispc_wb_enable(bool enable)
+{
+	enum omap_plane plane = OMAP_DSS_WB;
+	struct completion frame_done_completion;
+	bool is_on;
+	int r;
+	u32 irq;
+
+	is_on = REG_GET(DISPC_OVL_ATTRIBUTES(plane), 0, 0);
+	irq = DISPC_IRQ_FRAMEDONEWB;
+
+	if (!enable && is_on) {
+		init_completion(&frame_done_completion);
+
+		r = omap_dispc_register_isr(dispc_disable_isr,
+				&frame_done_completion, irq);
+		if (r)
+			DSSERR("failed to register FRAMEDONEWB isr\n");
+	}
+
+	REG_FLD_MOD(DISPC_OVL_ATTRIBUTES(plane), enable ? 1 : 0, 0, 0);
+
+	if (!enable && is_on) {
+		if (!wait_for_completion_timeout(&frame_done_completion,
+					msecs_to_jiffies(100)))
+			DSSERR("timeout waiting for FRAMEDONEWB\n");
+
+		r = omap_dispc_unregister_isr(dispc_disable_isr,
+				&frame_done_completion, irq);
+		if (r)
+			DSSERR("failed to unregister FRAMEDONEWB isr\n");
+	}
+}
+
+bool dispc_wb_is_enabled(void)
+{
+	enum omap_plane plane = OMAP_DSS_WB;
+
+	return REG_GET(DISPC_OVL_ATTRIBUTES(plane), 0, 0);
+}
+
 void dispc_lcd_enable_signal_polarity(bool act_high)
 {
 	if (!dss_has_feature(FEAT_LCDENABLEPOL))
@@ -2963,6 +3170,23 @@ unsigned long dispc_core_clk_rate(void)
 	return fclk / lcd;
 }
 
+static unsigned long dispc_plane_pclk_rate(enum omap_plane plane)
+{
+	enum omap_channel channel = dispc_ovl_get_channel_out(plane);
+
+	return dispc_mgr_pclk_rate(channel);
+}
+
+static unsigned long dispc_plane_lclk_rate(enum omap_plane plane)
+{
+	enum omap_channel channel = dispc_ovl_get_channel_out(plane);
+
+	if (dss_mgr_is_lcd(channel))
+		return dispc_mgr_lclk_rate(channel);
+	else
+		return dispc_fclk_rate();
+
+}
 static void dispc_dump_clocks_channel(struct seq_file *s, enum omap_channel channel)
 {
 	int lcd, pcd;
@@ -3756,7 +3980,7 @@ static void _omap_dispc_initial_config(void)
 	if (dss_has_feature(FEAT_FUNCGATED))
 		REG_FLD_MOD(DISPC_CONFIG, 1, 9, 9);
 
-	_dispc_setup_color_conv_coef();
+	dispc_setup_color_conv_coef();
 
 	dispc_set_loadmode(OMAP_DSS_LOAD_FRAME_ONLY);
 
diff --git a/drivers/video/omap2/dss/dispc.h b/drivers/video/omap2/dss/dispc.h
index 42e56cc7cdb..222363c6e62 100644
--- a/drivers/video/omap2/dss/dispc.h
+++ b/drivers/video/omap2/dss/dispc.h
@@ -373,6 +373,7 @@ static inline u16 DISPC_BA0_OFFSET(enum omap_plane plane)
 	case OMAP_DSS_VIDEO2:
 		return 0x0000;
 	case OMAP_DSS_VIDEO3:
+	case OMAP_DSS_WB:
 		return 0x0008;
 	default:
 		BUG();
@@ -388,6 +389,7 @@ static inline u16 DISPC_BA1_OFFSET(enum omap_plane plane)
 	case OMAP_DSS_VIDEO2:
 		return 0x0004;
 	case OMAP_DSS_VIDEO3:
+	case OMAP_DSS_WB:
 		return 0x000C;
 	default:
 		BUG();
@@ -407,6 +409,8 @@ static inline u16 DISPC_BA0_UV_OFFSET(enum omap_plane plane)
 		return 0x04BC;
 	case OMAP_DSS_VIDEO3:
 		return 0x0310;
+	case OMAP_DSS_WB:
+		return 0x0118;
 	default:
 		BUG();
 		return 0;
@@ -425,6 +429,8 @@ static inline u16 DISPC_BA1_UV_OFFSET(enum omap_plane plane)
 		return 0x04C0;
 	case OMAP_DSS_VIDEO3:
 		return 0x0314;
+	case OMAP_DSS_WB:
+		return 0x011C;
 	default:
 		BUG();
 		return 0;
@@ -454,6 +460,7 @@ static inline u16 DISPC_SIZE_OFFSET(enum omap_plane plane)
 	case OMAP_DSS_VIDEO2:
 		return 0x000C;
 	case OMAP_DSS_VIDEO3:
+	case OMAP_DSS_WB:
 		return 0x00A8;
 	default:
 		BUG();
@@ -470,6 +477,7 @@ static inline u16 DISPC_ATTR_OFFSET(enum omap_plane plane)
 	case OMAP_DSS_VIDEO2:
 		return 0x0010;
 	case OMAP_DSS_VIDEO3:
+	case OMAP_DSS_WB:
 		return 0x0070;
 	default:
 		BUG();
@@ -489,6 +497,8 @@ static inline u16 DISPC_ATTR2_OFFSET(enum omap_plane plane)
 		return 0x04DC;
 	case OMAP_DSS_VIDEO3:
 		return 0x032C;
+	case OMAP_DSS_WB:
+		return 0x0310;
 	default:
 		BUG();
 		return 0;
@@ -504,6 +514,7 @@ static inline u16 DISPC_FIFO_THRESH_OFFSET(enum omap_plane plane)
 	case OMAP_DSS_VIDEO2:
 		return 0x0014;
 	case OMAP_DSS_VIDEO3:
+	case OMAP_DSS_WB:
 		return 0x008C;
 	default:
 		BUG();
@@ -537,6 +548,7 @@ static inline u16 DISPC_ROW_INC_OFFSET(enum omap_plane plane)
 	case OMAP_DSS_VIDEO2:
 		return 0x001C;
 	case OMAP_DSS_VIDEO3:
+	case OMAP_DSS_WB:
 		return 0x00A4;
 	default:
 		BUG();
@@ -553,6 +565,7 @@ static inline u16 DISPC_PIX_INC_OFFSET(enum omap_plane plane)
 	case OMAP_DSS_VIDEO2:
 		return 0x0020;
 	case OMAP_DSS_VIDEO3:
+	case OMAP_DSS_WB:
 		return 0x0098;
 	default:
 		BUG();
@@ -602,6 +615,7 @@ static inline u16 DISPC_FIR_OFFSET(enum omap_plane plane)
 	case OMAP_DSS_VIDEO2:
 		return 0x0024;
 	case OMAP_DSS_VIDEO3:
+	case OMAP_DSS_WB:
 		return 0x0090;
 	default:
 		BUG();
@@ -621,6 +635,8 @@ static inline u16 DISPC_FIR2_OFFSET(enum omap_plane plane)
 		return 0x055C;
 	case OMAP_DSS_VIDEO3:
 		return 0x0424;
+	case OMAP_DSS_WB:
+		return 0x290;
 	default:
 		BUG();
 		return 0;
@@ -637,6 +653,7 @@ static inline u16 DISPC_PIC_SIZE_OFFSET(enum omap_plane plane)
 	case OMAP_DSS_VIDEO2:
 		return 0x0028;
 	case OMAP_DSS_VIDEO3:
+	case OMAP_DSS_WB:
 		return 0x0094;
 	default:
 		BUG();
@@ -655,6 +672,7 @@ static inline u16 DISPC_ACCU0_OFFSET(enum omap_plane plane)
 	case OMAP_DSS_VIDEO2:
 		return 0x002C;
 	case OMAP_DSS_VIDEO3:
+	case OMAP_DSS_WB:
 		return 0x0000;
 	default:
 		BUG();
@@ -674,6 +692,8 @@ static inline u16 DISPC_ACCU2_0_OFFSET(enum omap_plane plane)
 		return 0x0560;
 	case OMAP_DSS_VIDEO3:
 		return 0x0428;
+	case OMAP_DSS_WB:
+		return 0x0294;
 	default:
 		BUG();
 		return 0;
@@ -690,6 +710,7 @@ static inline u16 DISPC_ACCU1_OFFSET(enum omap_plane plane)
 	case OMAP_DSS_VIDEO2:
 		return 0x0030;
 	case OMAP_DSS_VIDEO3:
+	case OMAP_DSS_WB:
 		return 0x0004;
 	default:
 		BUG();
@@ -709,6 +730,8 @@ static inline u16 DISPC_ACCU2_1_OFFSET(enum omap_plane plane)
 		return 0x0564;
 	case OMAP_DSS_VIDEO3:
 		return 0x042C;
+	case OMAP_DSS_WB:
+		return 0x0298;
 	default:
 		BUG();
 		return 0;
@@ -726,6 +749,7 @@ static inline u16 DISPC_FIR_COEF_H_OFFSET(enum omap_plane plane, u16 i)
 	case OMAP_DSS_VIDEO2:
 		return 0x0034 + i * 0x8;
 	case OMAP_DSS_VIDEO3:
+	case OMAP_DSS_WB:
 		return 0x0010 + i * 0x8;
 	default:
 		BUG();
@@ -746,6 +770,8 @@ static inline u16 DISPC_FIR_COEF_H2_OFFSET(enum omap_plane plane, u16 i)
 		return 0x0568 + i * 0x8;
 	case OMAP_DSS_VIDEO3:
 		return 0x0430 + i * 0x8;
+	case OMAP_DSS_WB:
+		return 0x02A0 + i * 0x8;
 	default:
 		BUG();
 		return 0;
@@ -763,6 +789,7 @@ static inline u16 DISPC_FIR_COEF_HV_OFFSET(enum omap_plane plane, u16 i)
 	case OMAP_DSS_VIDEO2:
 		return 0x0038 + i * 0x8;
 	case OMAP_DSS_VIDEO3:
+	case OMAP_DSS_WB:
 		return 0x0014 + i * 0x8;
 	default:
 		BUG();
@@ -783,6 +810,8 @@ static inline u16 DISPC_FIR_COEF_HV2_OFFSET(enum omap_plane plane, u16 i)
 		return 0x056C + i * 0x8;
 	case OMAP_DSS_VIDEO3:
 		return 0x0434 + i * 0x8;
+	case OMAP_DSS_WB:
+		return 0x02A4 + i * 0x8;
 	default:
 		BUG();
 		return 0;
@@ -799,6 +828,7 @@ static inline u16 DISPC_CONV_COEF_OFFSET(enum omap_plane plane, u16 i)
 	case OMAP_DSS_VIDEO1:
 	case OMAP_DSS_VIDEO2:
 	case OMAP_DSS_VIDEO3:
+	case OMAP_DSS_WB:
 		return 0x0074 + i * 0x4;
 	default:
 		BUG();
@@ -818,6 +848,7 @@ static inline u16 DISPC_FIR_COEF_V_OFFSET(enum omap_plane plane, u16 i)
 	case OMAP_DSS_VIDEO2:
 		return 0x00B4 + i * 0x4;
 	case OMAP_DSS_VIDEO3:
+	case OMAP_DSS_WB:
 		return 0x0050 + i * 0x4;
 	default:
 		BUG();
@@ -838,6 +869,8 @@ static inline u16 DISPC_FIR_COEF_V2_OFFSET(enum omap_plane plane, u16 i)
 		return 0x05A8 + i * 0x4;
 	case OMAP_DSS_VIDEO3:
 		return 0x0470 + i * 0x4;
+	case OMAP_DSS_WB:
+		return 0x02E0 + i * 0x4;
 	default:
 		BUG();
 		return 0;
diff --git a/drivers/video/omap2/dss/dss.h b/drivers/video/omap2/dss/dss.h
index a14528bcfea..6728892f9da 100644
--- a/drivers/video/omap2/dss/dss.h
+++ b/drivers/video/omap2/dss/dss.h
@@ -113,6 +113,17 @@ enum dss_dsi_content_type {
 	DSS_DSI_CONTENT_GENERIC,
 };
 
+enum dss_writeback_channel {
+	DSS_WB_LCD1_MGR =	0,
+	DSS_WB_LCD2_MGR =	1,
+	DSS_WB_TV_MGR =		2,
+	DSS_WB_OVL0 =		3,
+	DSS_WB_OVL1 =		4,
+	DSS_WB_OVL2 =		5,
+	DSS_WB_OVL3 =		6,
+	DSS_WB_LCD3_MGR =	7,
+};
+
 struct dss_clock_info {
 	/* rates that we get with dividers below */
 	unsigned long fck;
@@ -444,8 +455,9 @@ void dispc_ovl_set_fifo_threshold(enum omap_plane plane, u32 low, u32 high);
 void dispc_ovl_compute_fifo_thresholds(enum omap_plane plane,
 		u32 *fifo_low, u32 *fifo_high, bool use_fifomerge,
 		bool manual_update);
-int dispc_ovl_setup(enum omap_plane plane, struct omap_overlay_info *oi,
-		bool replication, const struct omap_video_timings *mgr_timings);
+int dispc_ovl_setup(enum omap_plane plane, const struct omap_overlay_info *oi,
+		bool replication, const struct omap_video_timings *mgr_timings,
+		bool mem_to_mem);
 int dispc_ovl_enable(enum omap_plane plane, bool enable);
 void dispc_ovl_set_channel_out(enum omap_plane plane,
 		enum omap_channel channel);
@@ -474,6 +486,15 @@ int dispc_mgr_get_clock_div(enum omap_channel channel,
 void dispc_mgr_setup(enum omap_channel channel,
 		struct omap_overlay_manager_info *info);
 
+u32 dispc_wb_get_framedone_irq(void);
+bool dispc_wb_go_busy(void);
+void dispc_wb_go(void);
+void dispc_wb_enable(bool enable);
+bool dispc_wb_is_enabled(void);
+void dispc_wb_set_channel_in(enum dss_writeback_channel channel);
+int dispc_wb_setup(const struct omap_dss_writeback_info *wi,
+		bool mem_to_mem, const struct omap_video_timings *timings);
+
 /* VENC */
 #ifdef CONFIG_OMAP2_DSS_VENC
 int venc_init_platform_driver(void) __init;
diff --git a/drivers/video/omap2/dss/dss_features.c b/drivers/video/omap2/dss/dss_features.c
index bfe7fc7b859..acbc1e1efba 100644
--- a/drivers/video/omap2/dss/dss_features.c
+++ b/drivers/video/omap2/dss/dss_features.c
@@ -46,6 +46,7 @@ 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;
@@ -310,58 +311,80 @@ static const enum omap_color_mode omap4_dss_supported_color_modes[] = {
 	OMAP_DSS_COLOR_ARGB16 | OMAP_DSS_COLOR_XRGB16_1555 |
 	OMAP_DSS_COLOR_ARGB32 | OMAP_DSS_COLOR_RGBX16 |
 	OMAP_DSS_COLOR_RGBX32,
+
+	/* OMAP_DSS_WB */
+	OMAP_DSS_COLOR_RGB16 | OMAP_DSS_COLOR_RGB12U |
+	OMAP_DSS_COLOR_YUV2 | OMAP_DSS_COLOR_ARGB16_1555 |
+	OMAP_DSS_COLOR_RGBA32 | OMAP_DSS_COLOR_NV12 |
+	OMAP_DSS_COLOR_RGBA16 | OMAP_DSS_COLOR_RGB24U |
+	OMAP_DSS_COLOR_RGB24P | OMAP_DSS_COLOR_UYVY |
+	OMAP_DSS_COLOR_ARGB16 | OMAP_DSS_COLOR_XRGB16_1555 |
+	OMAP_DSS_COLOR_ARGB32 | OMAP_DSS_COLOR_RGBX16 |
+	OMAP_DSS_COLOR_RGBX32,
 };
 
 static const enum omap_overlay_caps omap2_dss_overlay_caps[] = {
 	/* OMAP_DSS_GFX */
-	0,
+	OMAP_DSS_OVL_CAP_POS | OMAP_DSS_OVL_CAP_REPLICATION,
 
 	/* OMAP_DSS_VIDEO1 */
-	OMAP_DSS_OVL_CAP_SCALE,
+	OMAP_DSS_OVL_CAP_SCALE | OMAP_DSS_OVL_CAP_POS |
+		OMAP_DSS_OVL_CAP_REPLICATION,
 
 	/* OMAP_DSS_VIDEO2 */
-	OMAP_DSS_OVL_CAP_SCALE,
+	OMAP_DSS_OVL_CAP_SCALE | OMAP_DSS_OVL_CAP_POS |
+		OMAP_DSS_OVL_CAP_REPLICATION,
 };
 
 static const enum omap_overlay_caps omap3430_dss_overlay_caps[] = {
 	/* OMAP_DSS_GFX */
-	OMAP_DSS_OVL_CAP_GLOBAL_ALPHA,
+	OMAP_DSS_OVL_CAP_GLOBAL_ALPHA | OMAP_DSS_OVL_CAP_POS |
+		OMAP_DSS_OVL_CAP_REPLICATION,
 
 	/* OMAP_DSS_VIDEO1 */
-	OMAP_DSS_OVL_CAP_SCALE,
+	OMAP_DSS_OVL_CAP_SCALE | OMAP_DSS_OVL_CAP_POS |
+		OMAP_DSS_OVL_CAP_REPLICATION,
 
 	/* OMAP_DSS_VIDEO2 */
-	OMAP_DSS_OVL_CAP_SCALE | OMAP_DSS_OVL_CAP_GLOBAL_ALPHA,
+	OMAP_DSS_OVL_CAP_SCALE | OMAP_DSS_OVL_CAP_GLOBAL_ALPHA |
+		OMAP_DSS_OVL_CAP_POS | OMAP_DSS_OVL_CAP_REPLICATION,
 };
 
 static const enum omap_overlay_caps omap3630_dss_overlay_caps[] = {
 	/* OMAP_DSS_GFX */
-	OMAP_DSS_OVL_CAP_GLOBAL_ALPHA | OMAP_DSS_OVL_CAP_PRE_MULT_ALPHA,
+	OMAP_DSS_OVL_CAP_GLOBAL_ALPHA | OMAP_DSS_OVL_CAP_PRE_MULT_ALPHA |
+		OMAP_DSS_OVL_CAP_POS | OMAP_DSS_OVL_CAP_REPLICATION,
 
 	/* OMAP_DSS_VIDEO1 */
-	OMAP_DSS_OVL_CAP_SCALE,
+	OMAP_DSS_OVL_CAP_SCALE | OMAP_DSS_OVL_CAP_POS |
+		OMAP_DSS_OVL_CAP_REPLICATION,
 
 	/* OMAP_DSS_VIDEO2 */
 	OMAP_DSS_OVL_CAP_SCALE | OMAP_DSS_OVL_CAP_GLOBAL_ALPHA |
-		OMAP_DSS_OVL_CAP_PRE_MULT_ALPHA,
+		OMAP_DSS_OVL_CAP_PRE_MULT_ALPHA | OMAP_DSS_OVL_CAP_POS |
+		OMAP_DSS_OVL_CAP_REPLICATION,
 };
 
 static const enum omap_overlay_caps omap4_dss_overlay_caps[] = {
 	/* OMAP_DSS_GFX */
 	OMAP_DSS_OVL_CAP_GLOBAL_ALPHA | OMAP_DSS_OVL_CAP_PRE_MULT_ALPHA |
-		OMAP_DSS_OVL_CAP_ZORDER,
+		OMAP_DSS_OVL_CAP_ZORDER | OMAP_DSS_OVL_CAP_POS |
+		OMAP_DSS_OVL_CAP_REPLICATION,
 
 	/* OMAP_DSS_VIDEO1 */
 	OMAP_DSS_OVL_CAP_SCALE | OMAP_DSS_OVL_CAP_GLOBAL_ALPHA |
-		OMAP_DSS_OVL_CAP_PRE_MULT_ALPHA | OMAP_DSS_OVL_CAP_ZORDER,
+		OMAP_DSS_OVL_CAP_PRE_MULT_ALPHA | OMAP_DSS_OVL_CAP_ZORDER |
+		OMAP_DSS_OVL_CAP_POS | OMAP_DSS_OVL_CAP_REPLICATION,
 
 	/* OMAP_DSS_VIDEO2 */
 	OMAP_DSS_OVL_CAP_SCALE | OMAP_DSS_OVL_CAP_GLOBAL_ALPHA |
-		OMAP_DSS_OVL_CAP_PRE_MULT_ALPHA | OMAP_DSS_OVL_CAP_ZORDER,
+		OMAP_DSS_OVL_CAP_PRE_MULT_ALPHA | OMAP_DSS_OVL_CAP_ZORDER |
+		OMAP_DSS_OVL_CAP_POS | OMAP_DSS_OVL_CAP_REPLICATION,
 
 	/* OMAP_DSS_VIDEO3 */
 	OMAP_DSS_OVL_CAP_SCALE | OMAP_DSS_OVL_CAP_GLOBAL_ALPHA |
-		OMAP_DSS_OVL_CAP_PRE_MULT_ALPHA | OMAP_DSS_OVL_CAP_ZORDER,
+		OMAP_DSS_OVL_CAP_PRE_MULT_ALPHA | OMAP_DSS_OVL_CAP_ZORDER |
+		OMAP_DSS_OVL_CAP_POS | OMAP_DSS_OVL_CAP_REPLICATION,
 };
 
 static const char * const omap2_dss_clk_source_names[] = {
@@ -698,6 +721,7 @@ 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,
@@ -719,6 +743,7 @@ 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,
@@ -740,6 +765,7 @@ 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,
@@ -817,6 +843,11 @@ int dss_feat_get_num_ovls(void)
 	return omap_current_dss_features->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;
diff --git a/drivers/video/omap2/dss/dss_features.h b/drivers/video/omap2/dss/dss_features.h
index 89df2aa860d..9218113b5e8 100644
--- a/drivers/video/omap2/dss/dss_features.h
+++ b/drivers/video/omap2/dss/dss_features.h
@@ -105,6 +105,7 @@ enum dss_range_param {
 /* DSS Feature Functions */
 int dss_feat_get_num_mgrs(void);
 int dss_feat_get_num_ovls(void);
+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_display_type dss_feat_get_supported_displays(enum omap_channel channel);
diff --git a/include/video/omapdss.h b/include/video/omapdss.h
index e65e2e9e16e..3729173b7fb 100644
--- a/include/video/omapdss.h
+++ b/include/video/omapdss.h
@@ -187,6 +187,8 @@ enum omap_overlay_caps {
 	OMAP_DSS_OVL_CAP_GLOBAL_ALPHA = 1 << 1,
 	OMAP_DSS_OVL_CAP_PRE_MULT_ALPHA = 1 << 2,
 	OMAP_DSS_OVL_CAP_ZORDER = 1 << 3,
+	OMAP_DSS_OVL_CAP_POS = 1 << 4,
+	OMAP_DSS_OVL_CAP_REPLICATION = 1 << 5,
 };
 
 enum omap_overlay_manager_caps {
@@ -508,6 +510,19 @@ struct omap_dsi_pin_config {
 	int pins[OMAP_DSS_MAX_DSI_PINS];
 };
 
+struct omap_dss_writeback_info {
+	u32 paddr;
+	u32 p_uv_addr;
+	u16 buf_width;
+	u16 width;
+	u16 height;
+	enum omap_color_mode color_mode;
+	u8 rotation;
+	enum omap_dss_rotation_type rotation_type;
+	bool mirror;
+	u8 pre_mult_alpha;
+};
+
 struct omap_dss_output {
 	struct list_head list;