diff options
author | Russell King <rmk+kernel@arm.linux.org.uk> | 2011-01-21 14:03:28 (GMT) |
---|---|---|
committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2011-02-19 11:09:05 (GMT) |
commit | 7b4e9ced69a120e7e7446e3303d2307aa29d891c (patch) | |
tree | a39b9782e2aa4e9f7f386dade06111fe0c6c3f34 /drivers/video/amba-clcd.c | |
parent | 9c49e4ab84dd46769e7fd9773946e10c95bab680 (diff) | |
download | linux-7b4e9ced69a120e7e7446e3303d2307aa29d891c.tar.xz |
ARM: clcd: add method for describing display capabilities
The ARM CLCD PL110 controller in TFT mode provides two output formats
based on whether the controller is in 24bpp mode or not - either 5551
or 888. PL111 augments this with a 444 and 565 modes.
Some implementations provide an external MUX on the PL110 output to
reassign the bits to achieve 565 mode.
Provide a system of capability flags to allow the CLCD driver to work
out what is supported by each panel and board, and therefore which
display formats are permitted.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'drivers/video/amba-clcd.c')
-rw-r--r-- | drivers/video/amba-clcd.c | 95 |
1 files changed, 84 insertions, 11 deletions
diff --git a/drivers/video/amba-clcd.c b/drivers/video/amba-clcd.c index aedbb34..8bd3706 100644 --- a/drivers/video/amba-clcd.c +++ b/drivers/video/amba-clcd.c @@ -120,8 +120,23 @@ static void clcdfb_enable(struct clcd_fb *fb, u32 cntl) static int clcdfb_set_bitfields(struct clcd_fb *fb, struct fb_var_screeninfo *var) { + u32 caps; int ret = 0; + if (fb->panel->caps && fb->board->caps) + caps = fb->panel->caps & fb->board->caps; + else { + /* Old way of specifying what can be used */ + caps = fb->panel->cntl & CNTL_BGR ? + CLCD_CAP_BGR : CLCD_CAP_RGB; + /* But mask out 444 modes as they weren't supported */ + caps &= ~CLCD_CAP_444; + } + + /* Only TFT panels can do RGB888/BGR888 */ + if (!(fb->panel->cntl & CNTL_LCDTFT)) + caps &= ~CLCD_CAP_888; + memset(&var->transp, 0, sizeof(var->transp)); var->red.msb_right = 0; @@ -133,6 +148,13 @@ clcdfb_set_bitfields(struct clcd_fb *fb, struct fb_var_screeninfo *var) case 2: case 4: case 8: + /* If we can't do 5551, reject */ + caps &= CLCD_CAP_5551; + if (!caps) { + ret = -EINVAL; + break; + } + var->red.length = var->bits_per_pixel; var->red.offset = 0; var->green.length = var->bits_per_pixel; @@ -140,23 +162,61 @@ clcdfb_set_bitfields(struct clcd_fb *fb, struct fb_var_screeninfo *var) var->blue.length = var->bits_per_pixel; var->blue.offset = 0; break; + case 16: - var->red.length = 5; - var->blue.length = 5; + /* If we can't do 444, 5551 or 565, reject */ + if (!(caps & (CLCD_CAP_444 | CLCD_CAP_5551 | CLCD_CAP_565))) { + ret = -EINVAL; + break; + } + /* - * Green length can be 5 or 6 depending whether - * we're operating in RGB555 or RGB565 mode. + * Green length can be 4, 5 or 6 depending whether + * we're operating in 444, 5551 or 565 mode. */ - if (var->green.length != 5 && var->green.length != 6) - var->green.length = 6; + if (var->green.length == 4 && caps & CLCD_CAP_444) + caps &= CLCD_CAP_444; + if (var->green.length == 5 && caps & CLCD_CAP_5551) + caps &= CLCD_CAP_5551; + else if (var->green.length == 6 && caps & CLCD_CAP_565) + caps &= CLCD_CAP_565; + else { + /* + * PL110 officially only supports RGB555, + * but may be wired up to allow RGB565. + */ + if (caps & CLCD_CAP_565) { + var->green.length = 6; + caps &= CLCD_CAP_565; + } else if (caps & CLCD_CAP_5551) { + var->green.length = 5; + caps &= CLCD_CAP_5551; + } else { + var->green.length = 4; + caps &= CLCD_CAP_444; + } + } + + if (var->green.length >= 5) { + var->red.length = 5; + var->blue.length = 5; + } else { + var->red.length = 4; + var->blue.length = 4; + } break; case 32: - if (fb->panel->cntl & CNTL_LCDTFT) { - var->red.length = 8; - var->green.length = 8; - var->blue.length = 8; + /* If we can't do 888, reject */ + caps &= CLCD_CAP_888; + if (!caps) { + ret = -EINVAL; break; } + + var->red.length = 8; + var->green.length = 8; + var->blue.length = 8; + break; default: ret = -EINVAL; break; @@ -168,7 +228,20 @@ clcdfb_set_bitfields(struct clcd_fb *fb, struct fb_var_screeninfo *var) * the bitfield length defined above. */ if (ret == 0 && var->bits_per_pixel >= 16) { - if (fb->panel->cntl & CNTL_BGR) { + bool bgr, rgb; + + bgr = caps & CLCD_CAP_BGR && var->blue.offset == 0; + rgb = caps & CLCD_CAP_RGB && var->red.offset == 0; + + if (!bgr && !rgb) + /* + * The requested format was not possible, try just + * our capabilities. One of BGR or RGB must be + * supported. + */ + bgr = caps & CLCD_CAP_BGR; + + if (bgr) { var->blue.offset = 0; var->green.offset = var->blue.offset + var->blue.length; var->red.offset = var->green.offset + var->green.length; |