drm_fb_xrgb8888_to_gray2() works like and share much code with drm_fb_xrgb8888_to_mono(), but converts XRGB8888 to 2bit grayscale instead.
It uses drm_fb_xrgb8888_to_gray8() to convert the pixels to gray8 as an intermediate step before converting to gray2. Signed-off-by: Marcus Folkesson <[email protected]> --- drivers/gpu/drm/drm_format_helper.c | 148 ++++++++++++++++++++++++++---------- include/drm/drm_format_helper.h | 4 + 2 files changed, 110 insertions(+), 42 deletions(-) diff --git a/drivers/gpu/drm/drm_format_helper.c b/drivers/gpu/drm/drm_format_helper.c index 8f3daf38ca639d3d39742c2c9fa0c54a3a9297a5..2f2171b3df609263cc9ce6809bf6144028c25380 100644 --- a/drivers/gpu/drm/drm_format_helper.c +++ b/drivers/gpu/drm/drm_format_helper.c @@ -1253,6 +1253,25 @@ int drm_fb_blit(struct iosys_map *dst, const unsigned int *dst_pitch, uint32_t d } EXPORT_SYMBOL(drm_fb_blit); +static void drm_fb_gray8_to_gray2_line(void *dbuf, const void *sbuf, unsigned int pixels) +{ + u8 *dbuf8 = dbuf; + const u8 *sbuf8 = sbuf; + u8 px; + + while (pixels) { + unsigned int i, bits = min(pixels, 4U); + u8 byte = 0; + + for (i = 0; i < bits; i++, pixels--) { + byte >>= 2; + px = (*sbuf8++ * 3 + 127) / 255; + byte |= (px &= 0x03) << 6; + } + *dbuf8++ = byte; + } +} + static void drm_fb_gray8_to_mono_line(void *dbuf, const void *sbuf, unsigned int pixels) { u8 *dbuf8 = dbuf; @@ -1270,40 +1289,11 @@ static void drm_fb_gray8_to_mono_line(void *dbuf, const void *sbuf, unsigned int } } -/** - * drm_fb_xrgb8888_to_mono - Convert XRGB8888 to monochrome - * @dst: Array of monochrome destination buffers (0=black, 1=white) - * @dst_pitch: Array of numbers of bytes between the start of two consecutive scanlines - * within @dst; can be NULL if scanlines are stored next to each other. - * @src: Array of XRGB8888 source buffers - * @fb: DRM framebuffer - * @clip: Clip rectangle area to copy - * @state: Transform and conversion state - * - * This function copies parts of a framebuffer to display memory and converts the - * color format during the process. Destination and framebuffer formats must match. The - * parameters @dst, @dst_pitch and @src refer to arrays. Each array must have at - * least as many entries as there are planes in @fb's format. Each entry stores the - * value for the format's respective color plane at the same index. - * - * This function does not apply clipping on @dst (i.e. the destination is at the - * top-left corner). The first pixel (upper left corner of the clip rectangle) will - * be converted and copied to the first bit (LSB) in the first byte of the monochrome - * destination buffer. If the caller requires that the first pixel in a byte must - * be located at an x-coordinate that is a multiple of 8, then the caller must take - * care itself of supplying a suitable clip rectangle. - * - * DRM doesn't have native monochrome support. Drivers can use this function for - * monochrome devices that don't support XRGB8888 natively. Such drivers can - * announce the commonly supported XR24 format to userspace and use this function - * to convert to the native format. - * - * This function uses drm_fb_xrgb8888_to_gray8() to convert to grayscale and - * then the result is converted from grayscale to monochrome. - */ -void drm_fb_xrgb8888_to_mono(struct iosys_map *dst, const unsigned int *dst_pitch, - const struct iosys_map *src, const struct drm_framebuffer *fb, - const struct drm_rect *clip, struct drm_format_conv_state *state) +static void drm_fb_xrgb8888_to_gray(u8 *dst, const unsigned int *dst_pitch, + u8 *src, const struct drm_framebuffer *fb, + const struct drm_rect *clip, struct drm_format_conv_state *state, + u8 bpp, + void (*xfrm_line)(void *dbuf, const void *sbuf, unsigned int npixels)) { static const unsigned int default_dst_pitch[DRM_FORMAT_MAX_PLANES] = { 0, 0, 0, 0 @@ -1313,11 +1303,10 @@ void drm_fb_xrgb8888_to_mono(struct iosys_map *dst, const unsigned int *dst_pitc unsigned int cpp = fb->format->cpp[0]; unsigned int len_src32 = linepixels * cpp; struct drm_device *dev = fb->dev; - void *vaddr = src[0].vaddr; unsigned int dst_pitch_0; unsigned int y; - u8 *mono = dst[0].vaddr, *gray8; u32 *src32; + u8 *gray8; if (drm_WARN_ON(dev, fb->format->format != DRM_FORMAT_XRGB8888)) return; @@ -1330,7 +1319,7 @@ void drm_fb_xrgb8888_to_mono(struct iosys_map *dst, const unsigned int *dst_pitc * The mono destination buffer contains 1 bit per pixel */ if (!dst_pitch_0) - dst_pitch_0 = DIV_ROUND_UP(linepixels, 8); + dst_pitch_0 = DIV_ROUND_UP(linepixels, 8 / bpp); /* * The dma memory is write-combined so reads are uncached. @@ -1349,13 +1338,88 @@ void drm_fb_xrgb8888_to_mono(struct iosys_map *dst, const unsigned int *dst_pitc gray8 = (u8 *)src32 + len_src32; - vaddr += clip_offset(clip, fb->pitches[0], cpp); + src += clip_offset(clip, fb->pitches[0], cpp); for (y = 0; y < lines; y++) { - src32 = memcpy(src32, vaddr, len_src32); + src32 = memcpy(src32, src, len_src32); drm_fb_xrgb8888_to_gray8_line(gray8, src32, linepixels); - drm_fb_gray8_to_mono_line(mono, gray8, linepixels); - vaddr += fb->pitches[0]; - mono += dst_pitch_0; + xfrm_line(dst, gray8, linepixels); + src += fb->pitches[0]; + dst += dst_pitch_0; } } + +/** + * drm_fb_xrgb8888_to_mono - Convert XRGB8888 to monochrome + * @dst: Array of monochrome destination buffers (0=black, 1=white) + * @dst_pitch: Array of numbers of bytes between the start of two consecutive scanlines + * within @dst; can be NULL if scanlines are stored next to each other. + * @src: Array of XRGB8888 source buffers + * @fb: DRM framebuffer + * @clip: Clip rectangle area to copy + * @state: Transform and conversion state + * + * DRM doesn't have native monochrome support. Drivers can use this function for + * monochrome devices that don't support XRGB8888 natively. Such drivers can + * announce the commonly supported XR24 format to userspace and use this function + * to convert to the native format. + * + * This function copies parts of a framebuffer to display memory and converts the + * color format during the process. Destination and framebuffer formats must match. The + * parameters @dst, @dst_pitch and @src refer to arrays. Each array must have at + * least as many entries as there are planes in @fb's format. Each entry stores the + * value for the format's respective color plane at the same index. + * + * This function does not apply clipping on @dst (i.e. the destination is at the + * top-left corner). The first pixel (upper left corner of the clip rectangle) will + * be converted and copied to the first bit (LSB) in the first byte of the monochrome + * destination buffer. If the caller requires that the first pixel in a byte must + * be located at an x-coordinate that is a multiple of 8, then the caller must take + * care itself of supplying a suitable clip rectangle. + * + * + * This function uses drm_fb_xrgb8888_to_gray8() to convert to grayscale and + * then the result is converted from grayscale to monochrome. + */ + + +void drm_fb_xrgb8888_to_mono(struct iosys_map *dst, const unsigned int *dst_pitch, + const struct iosys_map *src, const struct drm_framebuffer *fb, + const struct drm_rect *clip, struct drm_format_conv_state *state) +{ + drm_fb_xrgb8888_to_gray(dst[0].vaddr, dst_pitch, src[0].vaddr, fb, clip, state, + 1, drm_fb_gray8_to_mono_line); +} EXPORT_SYMBOL(drm_fb_xrgb8888_to_mono); + +/** + * drm_fb_xrgb8888_to_gray2 - Convert XRGB8888 to gray2 + * @dst: Array of gray2 destination buffers + * @dst_pitch: Array of numbers of bytes between the start of two consecutive scanlines + * within @dst; can be NULL if scanlines are stored next to each other. + * @src: Array of XRGB8888 source buffers + * @fb: DRM framebuffer + * @clip: Clip rectangle area to copy + * @state: Transform and conversion state + * + * This function copies parts of a framebuffer to display memory and converts the + * color format during the process. Destination and framebuffer formats must match. The + * parameters @dst, @dst_pitch and @src refer to arrays. Each array must have at + * least as many entries as there are planes in @fb's format. Each entry stores the + * value for the format's respective color plane at the same index. + * + * DRM doesn't have native gray2 support. Drivers can use this function for + * gray2 devices that don't support XRGB8888 natively. Such drivers can + * announce the commonly supported XR24 format to userspace and use this function + * to convert to the native format. + * + * This function uses drm_fb_xrgb8888_to_gray8() to convert to grayscale and + * then the result is converted from grayscale to gray2. + */ +void drm_fb_xrgb8888_to_gray2(struct iosys_map *dst, const unsigned int *dst_pitch, + const struct iosys_map *src, const struct drm_framebuffer *fb, + const struct drm_rect *clip, struct drm_format_conv_state *state) +{ + drm_fb_xrgb8888_to_gray(dst[0].vaddr, dst_pitch, src[0].vaddr, fb, clip, state, + 2, drm_fb_gray8_to_gray2_line); +} +EXPORT_SYMBOL(drm_fb_xrgb8888_to_gray2); diff --git a/include/drm/drm_format_helper.h b/include/drm/drm_format_helper.h index 562bc383ece4e90d96aa92b47b4f69609f825a6e..8488befafb7e0e0311f87bd2fef5011bab45065b 100644 --- a/include/drm/drm_format_helper.h +++ b/include/drm/drm_format_helper.h @@ -136,4 +136,8 @@ void drm_fb_xrgb8888_to_mono(struct iosys_map *dst, const unsigned int *dst_pitc const struct iosys_map *src, const struct drm_framebuffer *fb, const struct drm_rect *clip, struct drm_format_conv_state *state); +void drm_fb_xrgb8888_to_gray2(struct iosys_map *dst, const unsigned int *dst_pitch, + const struct iosys_map *src, const struct drm_framebuffer *fb, + const struct drm_rect *clip, struct drm_format_conv_state *state); + #endif /* __LINUX_DRM_FORMAT_HELPER_H */ -- 2.49.0
