Add support for color-indexed frame buffer formats with two, four, and
sixteen colors to the DRM framebuffer helper functions:
1. Add support for 1, 2, and 4 bits per pixel to the damage helper,
2. For color-indexed modes, the length of the color bitfields must be
set to the color depth, else the logo code may pick a logo with too
many colors. Drop the incorrect DAC width comment, which
originates from the i915 driver.
3. Accept C[124] modes when validating or filling in struct
fb_var_screeninfo, and use the correct number of bits per pixel.
4. Set the visual to FB_VISUAL_PSEUDOCOLOR for all color-indexed
modes.
Signed-off-by: Geert Uytterhoeven
---
v2:
- Use drm_format_info_bpp() helper instead of deprecated .depth field
or format-dependent calculations,
- Use new .is_color_indexed field instead of checking against a list
of formats.
---
drivers/gpu/drm/drm_fb_helper.c | 101
1 file changed, 75 insertions(+), 26 deletions(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index ed43b987d306afce..ba1c303a294d8c6f 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -376,12 +376,31 @@ static void drm_fb_helper_damage_blit_real(struct
drm_fb_helper *fb_helper,
struct iosys_map *dst)
{
struct drm_framebuffer *fb = fb_helper->fb;
- unsigned int cpp = fb->format->cpp[0];
- size_t offset = clip->y1 * fb->pitches[0] + clip->x1 * cpp;
- void *src = fb_helper->fbdev->screen_buffer + offset;
- size_t len = (clip->x2 - clip->x1) * cpp;
+ size_t offset = clip->y1 * fb->pitches[0];
+ size_t len = clip->x2 - clip->x1;
unsigned int y;
+ void *src;
+ switch (drm_format_info_bpp(fb->format, 0)) {
+ case 1:
+ offset += clip->x1 / 8;
+ len = DIV_ROUND_UP(len + clip->x1 % 8, 8);
+ break;
+ case 2:
+ offset += clip->x1 / 4;
+ len = DIV_ROUND_UP(len + clip->x1 % 4, 4);
+ break;
+ case 4:
+ offset += clip->x1 / 2;
+ len = DIV_ROUND_UP(len + clip->x1 % 2, 2);
+ break;
+ default:
+ offset += clip->x1 * fb->format->cpp[0];
+ len *= fb->format->cpp[0];
+ break;
+ }
+
+ src = fb_helper->fbdev->screen_buffer + offset;
iosys_map_incr(dst, offset); /* go to first pixel within clip rect */
for (y = clip->y1; y < clip->y2; y++) {
@@ -1231,19 +1250,23 @@ static bool drm_fb_pixel_format_equal(const struct
fb_var_screeninfo *var_1,
}
static void drm_fb_helper_fill_pixel_fmt(struct fb_var_screeninfo *var,
-u8 depth)
+const struct drm_format_info *format)
{
- switch (depth) {
- case 8:
+ u8 depth = format->depth;
+
+ if (format->is_color_indexed) {
var->red.offset = 0;
var->green.offset = 0;
var->blue.offset = 0;
- var->red.length = 8; /* 8bit DAC */
- var->green.length = 8;
- var->blue.length = 8;
+ var->red.length = depth;
+ var->green.length = depth;
+ var->blue.length = depth;
var->transp.offset = 0;
var->transp.length = 0;
- break;
+ return;
+ }
+
+ switch (depth) {
case 15:
var->red.offset = 10;
var->green.offset = 5;
@@ -1298,7 +1321,9 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
{
struct drm_fb_helper *fb_helper = info->par;
struct drm_framebuffer *fb = fb_helper->fb;
+ const struct drm_format_info *format = fb->format;
struct drm_device *dev = fb_helper->dev;
+ unsigned int bpp;
if (in_dbg_master())
return -EINVAL;
@@ -1308,22 +1333,33 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo
*var,
var->pixclock = 0;
}
- if ((drm_format_info_block_width(fb->format, 0) > 1) ||
- (drm_format_info_block_height(fb->format, 0) > 1))
- return -EINVAL;
+ switch (format->format) {
+ case DRM_FORMAT_C1:
+ case DRM_FORMAT_C2:
+ case DRM_FORMAT_C4:
+ /* supported format with sub-byte pixels */
+ break;
+
+ default:
+ if ((drm_format_info_block_width(format, 0) > 1) ||
+ (drm_format_info_block_height(format, 0) > 1))
+ return -EINVAL;
+ break;
+ }
/*
* Changes struct fb_var_screeninfo are currently not pushed back
* to KMS, hence fail if different settings are requested.
*/
- if (var->bits_per_pixel > fb->format->cpp[0] * 8
