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()

6 files changed, 495 insertions, 185 deletions

diff --git a/drivers/video/omap2/dss/apply.c b/drivers/video/omap2/dss/apply.c
index 2b1fa851a8b9..19d66f471b4b 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 811fe381aaea..a173a9481a23 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 42e56cc7cdbc..222363c6e623 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 a14528bcfeab..6728892f9dad 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 bfe7fc7b8593..acbc1e1efba3 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 89df2aa860d4..9218113b5e88 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);