atmel_lcdfb: fix 16-bpp modes on older SOCs

Fix regression introduced by commit 787f9fd23283 ("atmel_lcdfb: support
16bit BGR:565 mode, remove unsupported 15bit modes") which broke 16-bpp
modes for older SOCs which use IBGR:555 (msb is intensity) rather
than BGR:565.

Use SOC-type to determine the pixel layout.

Tested on at91sam9263 and at91sam9g45.

Cc: <stable@vger.kernel.org>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

1 files changed, 15 insertions, 7 deletions

diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
index 12cf5f31ee8f..025428e04c33 100644
--- a/drivers/video/atmel_lcdfb.c
+++ b/drivers/video/atmel_lcdfb.c
@@ -422,17 +422,22 @@ static int atmel_lcdfb_check_var(struct fb_var_screeninfo *var,
                         = var->bits_per_pixel;
                 break;
         case 16:
+                /* Older SOCs use IBGR:555 rather than BGR:565. */
+                if (sinfo->have_intensity_bit)
+                        var->green.length = 5;
+                else
+                        var->green.length = 6;
+
                 if (sinfo->lcd_wiring_mode == ATMEL_LCDC_WIRING_RGB) {
-                        /* RGB:565 mode */
-                        var->red.offset = 11;
+                        /* RGB:5X5 mode */
+                        var->red.offset = var->green.length + 5;
                         var->blue.offset = 0;
                 } else {
-                        /* BGR:565 mode */
+                        /* BGR:5X5 mode */
                         var->red.offset = 0;
-                        var->blue.offset = 11;
+                        var->blue.offset = var->green.length + 5;
                 }
                 var->green.offset = 5;
-                var->green.length = 6;
                 var->red.length = var->blue.length = 5;
                 break;
         case 32:
@@ -679,8 +684,7 @@ static int atmel_lcdfb_setcolreg(unsigned int regno, unsigned int red,
 
         case FB_VISUAL_PSEUDOCOLOR:
                 if (regno < 256) {
-                        if (cpu_is_at91sam9261() || cpu_is_at91sam9263()
-                            || cpu_is_at91sam9rl()) {
+                        if (sinfo->have_intensity_bit) {
                                 /* old style I+BGR:555 */
                                 val  = ((red   >> 11) & 0x001f);
                                 val |= ((green >>  6) & 0x03e0);
@@ -870,6 +874,10 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
         }
         sinfo->info = info;
         sinfo->pdev = pdev;
+        if (cpu_is_at91sam9261() || cpu_is_at91sam9263() ||
+                                                        cpu_is_at91sam9rl()) {
+                sinfo->have_intensity_bit = true;
+        }
 
         strcpy(info->fix.id, sinfo->pdev->name);
         info->flags = ATMEL_LCDFB_FBINFO_DEFAULT;