fbdev: sh_mobile_lcdc: Add YUV framebuffer support

Supports YCbCr420sp, YCbCr422sp, and YCbCr44sp, formats
(bpp = 12, 16, and 24) respectively.

When double-buffering both Y planes appear before the C planes (Y-Y-C-C),
as opposed to  Y-C-Y-C.

Set .nonstd in struct sh_mobile_lcdc_chan_cfg to enable YUV mode, and use
.bpp to distiguish between the 3 modes.
The value of .nonstd is copied to bits 16-31 of LDDFR in the LCDC and
should be set accordingly.
.nonstd must be set to 0 for RGB mode.

Due to the encoding of YUV data, the framebuffer will clear to green
instead of black.

In YUV 420 mode, panning is only possible in 2 line increments.
Additionally in YUV 420 mode the vertical resolution of the framebuffer
must be an even number.

Signed-off-by: Damian Hobson-Garcia <dhobsong@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

3 files changed, 115 insertions, 29 deletions

diff --git a/drivers/video/sh_mobile_lcdcfb.c b/drivers/video/sh_mobile_lcdcfb.c
index e040e46d7d91..bf2629f83f40 100644
--- a/drivers/video/sh_mobile_lcdcfb.c
+++ b/drivers/video/sh_mobile_lcdcfb.c
@@ -69,6 +69,7 @@ static unsigned long lcdc_offs_mainlcd[NR_CH_REGS] = {
         [LDSM1R] = 0x428,
         [LDSM2R] = 0x42c,
         [LDSA1R] = 0x430,
+        [LDSA2R] = 0x434,
         [LDMLSR] = 0x438,
         [LDHCNR] = 0x448,
         [LDHSYNR] = 0x44c,
@@ -153,6 +154,7 @@ static bool banked(int reg_nr)
         case LDDFR:
         case LDSM1R:
         case LDSA1R:
+        case LDSA2R:
         case LDMLSR:
         case LDHCNR:
         case LDHSYNR:
@@ -465,6 +467,7 @@ static int sh_mobile_lcdc_start(struct sh_mobile_lcdc_priv *priv)
         struct sh_mobile_lcdc_board_cfg *board_cfg;
         unsigned long tmp;
         int bpp = 0;
+        unsigned long ldddsr;
         int k, m;
         int ret = 0;
 
@@ -543,16 +546,21 @@ static int sh_mobile_lcdc_start(struct sh_mobile_lcdc_priv *priv)
         }
 
         /* word and long word swap */
-        switch (bpp) {
-        case 16:
-                lcdc_write(priv, _LDDDSR, lcdc_read(priv, _LDDDSR) | 6);
-                break;
-        case 24:
-                lcdc_write(priv, _LDDDSR, lcdc_read(priv, _LDDDSR) | 7);
-                break;
-        case 32:
-                lcdc_write(priv, _LDDDSR, lcdc_read(priv, _LDDDSR) | 4);
-                break;
+        ldddsr = lcdc_read(priv, _LDDDSR);
+        if  (priv->ch[0].info->var.nonstd)
+                lcdc_write(priv, _LDDDSR, ldddsr | 7);
+        else {
+                switch (bpp) {
+                case 16:
+                        lcdc_write(priv, _LDDDSR, ldddsr | 6);
+                        break;
+                case 24:
+                        lcdc_write(priv, _LDDDSR, ldddsr | 7);
+                        break;
+                case 32:
+                        lcdc_write(priv, _LDDDSR, ldddsr | 4);
+                        break;
+                }
         }
 
         for (k = 0; k < ARRAY_SIZE(priv->ch); k++) {
@@ -563,21 +571,40 @@ static int sh_mobile_lcdc_start(struct sh_mobile_lcdc_priv *priv)
 
                 /* set bpp format in PKF[4:0] */
                 tmp = lcdc_read_chan(ch, LDDFR);
-                tmp &= ~0x0001001f;
-                switch (ch->info->var.bits_per_pixel) {
-                case 16:
-                        tmp |= 0x03;
-                        break;
-                case 24:
-                        tmp |= 0x0b;
-                        break;
-                case 32:
-                        break;
+                tmp &= ~0x0003031f;
+                if (ch->info->var.nonstd) {
+                        tmp |= (ch->info->var.nonstd << 16);
+                        switch (ch->info->var.bits_per_pixel) {
+                        case 12:
+                                break;
+                        case 16:
+                                tmp |= (0x1 << 8);
+                                break;
+                        case 24:
+                                tmp |= (0x2 << 8);
+                                break;
+                        }
+                } else {
+                        switch (ch->info->var.bits_per_pixel) {
+                        case 16:
+                                tmp |= 0x03;
+                                break;
+                        case 24:
+                                tmp |= 0x0b;
+                                break;
+                        case 32:
+                                break;
+                        }
                 }
                 lcdc_write_chan(ch, LDDFR, tmp);
 
                 /* point out our frame buffer */
                 lcdc_write_chan(ch, LDSA1R, ch->info->fix.smem_start);
+                if (ch->info->var.nonstd)
+                        lcdc_write_chan(ch, LDSA2R,
+                                ch->info->fix.smem_start +
+                                ch->info->var.xres *
+                                ch->info->var.yres_virtual);
 
                 /* set line size */
                 lcdc_write_chan(ch, LDMLSR, ch->info->fix.line_length);
@@ -816,9 +843,15 @@ static int sh_mobile_fb_pan_display(struct fb_var_screeninfo *var,
         struct sh_mobile_lcdc_priv *priv = ch->lcdc;
         unsigned long ldrcntr;
         unsigned long new_pan_offset;
+        unsigned long base_addr_y, base_addr_c;
+        unsigned long c_offset;
 
-        new_pan_offset = (var->yoffset * info->fix.line_length) +
-                (var->xoffset * (info->var.bits_per_pixel / 8));
+        if (!var->nonstd)
+                new_pan_offset = (var->yoffset * info->fix.line_length) +
+                        (var->xoffset * (info->var.bits_per_pixel / 8));
+        else
+                new_pan_offset = (var->yoffset * info->fix.line_length) +
+                        (var->xoffset);
 
         if (new_pan_offset == ch->pan_offset)
                 return 0;       /* No change, do nothing */
@@ -826,7 +859,26 @@ static int sh_mobile_fb_pan_display(struct fb_var_screeninfo *var,
         ldrcntr = lcdc_read(priv, _LDRCNTR);
 
         /* Set the source address for the next refresh */
-        lcdc_write_chan_mirror(ch, LDSA1R, ch->dma_handle + new_pan_offset);
+        base_addr_y = ch->dma_handle + new_pan_offset;
+        if (var->nonstd) {
+                /* Set y offset */
+                c_offset = (var->yoffset *
+                        info->fix.line_length *
+                        (info->var.bits_per_pixel - 8)) / 8;
+                base_addr_c = ch->dma_handle + var->xres * var->yres_virtual +
+                        c_offset;
+                /* Set x offset */
+                if (info->var.bits_per_pixel == 24)
+                        base_addr_c += 2 * var->xoffset;
+                else
+                        base_addr_c += var->xoffset;
+        } else
+                base_addr_c = 0;
+
+        lcdc_write_chan_mirror(ch, LDSA1R, base_addr_y);
+        if (base_addr_c)
+                lcdc_write_chan_mirror(ch, LDSA2R, base_addr_c);
+
         if (lcdc_chan_is_sublcd(ch))
                 lcdc_write(ch->lcdc, _LDRCNTR, ldrcntr ^ LDRCNTR_SRS);
         else
@@ -897,7 +949,10 @@ static void sh_mobile_fb_reconfig(struct fb_info *info)
                 /* Couldn't reconfigure, hopefully, can continue as before */
                 return;
 
-        info->fix.line_length = mode1.xres * (ch->cfg.bpp / 8);
+        if (info->var.nonstd)
+                info->fix.line_length = mode1.xres;
+        else
+                info->fix.line_length = mode1.xres * (ch->cfg.bpp / 8);
 
         /*
          * fb_set_var() calls the notifier change internally, only if
@@ -1050,8 +1105,22 @@ static void sh_mobile_lcdc_bl_remove(struct backlight_device *bdev)
         backlight_device_unregister(bdev);
 }
 
-static int sh_mobile_lcdc_set_bpp(struct fb_var_screeninfo *var, int bpp)
+static int sh_mobile_lcdc_set_bpp(struct fb_var_screeninfo *var, int bpp,
+                                   int nonstd)
 {
+        if (nonstd) {
+                switch (bpp) {
+                case 12:
+                case 16:
+                case 24:
+                        var->bits_per_pixel = bpp;
+                        var->nonstd = nonstd;
+                        return 0;
+                default:
+                        return -EINVAL;
+                }
+        }
+
         switch (bpp) {
         case 16: /* PKF[4:0] = 00011 - RGB 565 */
                 var->red.offset = 11;
@@ -1334,6 +1403,14 @@ static int __devinit sh_mobile_lcdc_probe(struct platform_device *pdev)
                      k < cfg->num_cfg && lcd_cfg;
                      k++, lcd_cfg++) {
                         unsigned long size = lcd_cfg->yres * lcd_cfg->xres;
+                        /* NV12 buffers must have even number of lines */
+                        if ((cfg->nonstd) && cfg->bpp == 12 &&
+                                        (lcd_cfg->yres & 0x1)) {
+                                dev_err(&pdev->dev, "yres must be multiple of 2"
+                                                " for YCbCr420 mode.\n");
+                                error = -EINVAL;
+                                goto err1;
+                        }
 
                         if (size > max_size) {
                                 max_cfg = lcd_cfg;
@@ -1348,7 +1425,11 @@ static int __devinit sh_mobile_lcdc_probe(struct platform_device *pdev)
                                 max_cfg->xres, max_cfg->yres);
 
                 info->fix = sh_mobile_lcdc_fix;
-                info->fix.smem_len = max_size * (cfg->bpp / 8) * 2;
+                info->fix.smem_len = max_size * 2 * cfg->bpp / 8;
+
+                 /* Only pan in 2 line steps for NV12 */
+                if (cfg->nonstd && cfg->bpp == 12)
+                        info->fix.ypanstep = 2;
 
                 if (!mode) {
                         mode = &default_720p;
@@ -1366,7 +1447,7 @@ static int __devinit sh_mobile_lcdc_probe(struct platform_device *pdev)
                 var->yres_virtual = var->yres * 2;
                 var->activate = FB_ACTIVATE_NOW;
 
-                error = sh_mobile_lcdc_set_bpp(var, cfg->bpp);
+                error = sh_mobile_lcdc_set_bpp(var, cfg->bpp, cfg->nonstd);
                 if (error)
                         break;
 
@@ -1390,7 +1471,11 @@ static int __devinit sh_mobile_lcdc_probe(struct platform_device *pdev)
                 }
 
                 info->fix.smem_start = ch->dma_handle;
-                info->fix.line_length = var->xres * (cfg->bpp / 8);
+                if (var->nonstd)
+                        info->fix.line_length = var->xres;
+                else
+                        info->fix.line_length = var->xres * (cfg->bpp / 8);
+
                 info->screen_base = buf;
                 info->device = &pdev->dev;
                 ch->display_var = *var;
diff --git a/drivers/video/sh_mobile_lcdcfb.h b/drivers/video/sh_mobile_lcdcfb.h
index 03a22dcbcc59..4635eed63eee 100644
--- a/drivers/video/sh_mobile_lcdcfb.h
+++ b/drivers/video/sh_mobile_lcdcfb.h
@@ -8,7 +8,7 @@
 
 /* per-channel registers */
 enum { LDDCKPAT1R, LDDCKPAT2R, LDMT1R, LDMT2R, LDMT3R, LDDFR, LDSM1R,
-       LDSM2R, LDSA1R, LDMLSR, LDHCNR, LDHSYNR, LDVLNR, LDVSYNR, LDPMR,
+       LDSM2R, LDSA1R, LDSA2R, LDMLSR, LDHCNR, LDHSYNR, LDVLNR, LDVSYNR, LDPMR,
        LDHAJR,
        NR_CH_REGS };
 
diff --git a/include/video/sh_mobile_lcdc.h b/include/video/sh_mobile_lcdc.h
index f2e6ab857fa8..2c8d369190b3 100644
--- a/include/video/sh_mobile_lcdc.h
+++ b/include/video/sh_mobile_lcdc.h
@@ -86,6 +86,7 @@ struct sh_mobile_lcdc_chan_cfg {
         struct sh_mobile_lcdc_board_cfg board_cfg;
         struct sh_mobile_lcdc_bl_info bl_info;
         struct sh_mobile_lcdc_sys_bus_cfg sys_bus_cfg; /* only for SYSn I/F */
+        int nonstd;
 };
 
 struct sh_mobile_lcdc_info {