Pull the per-line conversion logic into a separate helper function. This will allow to do line-by-line conversion in other helpers that convert to a gray8 format. Suggested-by: Thomas Zimmermann <tzimmermann@xxxxxxx> Signed-off-by: Javier Martinez Canillas <javierm@xxxxxxxxxx> --- (no changes since v3) Changes in v3: - Add a drm_fb_xrgb8888_to_gray8_line() helper function (Thomas Zimmermann) drivers/gpu/drm/drm_format_helper.c | 31 ++++++++++++++++++----------- 1 file changed, 19 insertions(+), 12 deletions(-) diff --git a/drivers/gpu/drm/drm_format_helper.c b/drivers/gpu/drm/drm_format_helper.c index 0f28dd2bdd72..b981712623d3 100644 --- a/drivers/gpu/drm/drm_format_helper.c +++ b/drivers/gpu/drm/drm_format_helper.c @@ -464,6 +464,21 @@ void drm_fb_xrgb8888_to_xrgb2101010_toio(void __iomem *dst, } EXPORT_SYMBOL(drm_fb_xrgb8888_to_xrgb2101010_toio); +static void drm_fb_xrgb8888_to_gray8_line(u8 *dst, const u32 *src, unsigned int pixels) +{ + unsigned int x; + + for (x = 0; x < pixels; x++) { + u8 r = (*src & 0x00ff0000) >> 16; + u8 g = (*src & 0x0000ff00) >> 8; + u8 b = *src & 0x000000ff; + + /* ITU BT.601: Y = 0.299 R + 0.587 G + 0.114 B */ + *dst++ = (3 * r + 6 * g + b) / 10; + src++; + } +} + /** * drm_fb_xrgb8888_to_gray8 - Convert XRGB8888 to grayscale * @dst: 8-bit grayscale destination buffer @@ -484,8 +499,9 @@ EXPORT_SYMBOL(drm_fb_xrgb8888_to_xrgb2101010_toio); void drm_fb_xrgb8888_to_gray8(void *dst, unsigned int dst_pitch, const void *vaddr, const struct drm_framebuffer *fb, const struct drm_rect *clip) { - unsigned int len = (clip->x2 - clip->x1) * sizeof(u32); - unsigned int x, y; + unsigned int linepixels = clip->x2 - clip->x1; + unsigned int len = linepixels * sizeof(u32); + unsigned int y; void *buf; u8 *dst8; u32 *src32; @@ -508,16 +524,7 @@ void drm_fb_xrgb8888_to_gray8(void *dst, unsigned int dst_pitch, const void *vad for (y = clip->y1; y < clip->y2; y++) { dst8 = dst; src32 = memcpy(buf, vaddr, len); - for (x = clip->x1; x < clip->x2; x++) { - u8 r = (*src32 & 0x00ff0000) >> 16; - u8 g = (*src32 & 0x0000ff00) >> 8; - u8 b = *src32 & 0x000000ff; - - /* ITU BT.601: Y = 0.299 R + 0.587 G + 0.114 B */ - *dst8++ = (3 * r + 6 * g + b) / 10; - src32++; - } - + drm_fb_xrgb8888_to_gray8_line(dst8, src32, linepixels); vaddr += fb->pitches[0]; dst += dst_pitch; } -- 2.34.1