Unverified Commit 100d457c authored by Marcus Folkesson's avatar Marcus Folkesson Committed by Javier Martinez Canillas
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drm/st7571-i2c: add support for 2bit grayscale for XRGB8888 



Add support for 2bit grayscale and use it for XRGB8888 when grayscale is
supported.

Reviewed-by: default avatarJavier Martinez Canillas <javierm@redhat.com>
Signed-off-by: default avatarMarcus Folkesson <marcus.folkesson@gmail.com>
Link: https://lore.kernel.org/r/20250721-st7571-format-v2-6-159f4134098c@gmail.com


Signed-off-by: default avatarJavier Martinez Canillas <javierm@redhat.com>
parent 8bde81ec

drivers/gpu/drm/sitronix/st7571-i2c.c

+13 −13
Original line number Diff line number Diff line
@@ -219,10 +219,11 @@ static int st7571_send_command_list(struct st7571_device *st7571, 
	return ret;

}



static inline u8 st7571_transform_xy(const char *p, int x, int y)

static inline u8 st7571_transform_xy(const char *p, int x, int y, u8 bpp)

{

	int xrest = x % 8;

	u8 result = 0;

	u8 row_len = 16 * bpp;



	/*

	 * Transforms an (x, y) pixel coordinate into a vertical 8-bit
@@ -237,7 +238,7 @@ static inline u8 st7571_transform_xy(const char *p, int x, int y) 


	for (int i = 0; i < 8; i++) {

		int row_idx = y + i;

		u8 byte = p[row_idx * 16 + x];

		u8 byte = p[row_idx * row_len + x];

		u8 bit = (byte >> xrest) & 1;



		result |= (bit << i);
@@ -304,11 +305,11 @@ static void st7571_prepare_buffer_grayscale(struct st7571_device *st7571, 
	struct iosys_map dst;



	switch (fb->format->format) {

	case DRM_FORMAT_XRGB8888: /* Only support XRGB8888 in monochrome mode */

		dst_pitch = DIV_ROUND_UP(drm_rect_width(rect), 8);

	case DRM_FORMAT_XRGB8888:

		dst_pitch = DIV_ROUND_UP(drm_rect_width(rect), 4);

		iosys_map_set_vaddr(&dst, st7571->hwbuf);



		drm_fb_xrgb8888_to_mono(&dst, &dst_pitch, vmap, fb, rect, fmtcnv_state);

		drm_fb_xrgb8888_to_gray2(&dst, &dst_pitch, vmap, fb, rect, fmtcnv_state);

		break;



	case DRM_FORMAT_R1:
@@ -334,7 +335,7 @@ static int st7571_fb_update_rect_monochrome(struct drm_framebuffer *fb, struct d 


	for (int y = rect->y1; y < rect->y2; y += ST7571_PAGE_HEIGHT) {

		for (int x = rect->x1; x < rect->x2; x++)

			row[x] = st7571_transform_xy(st7571->hwbuf, x, y);

			row[x] = st7571_transform_xy(st7571->hwbuf, x, y, 1);



		st7571_set_position(st7571, rect->x1, y);
@@ -359,14 +360,13 @@ static int st7571_fb_update_rect_grayscale(struct drm_framebuffer *fb, struct dr 
	rect->y2 = min_t(unsigned int, round_up(rect->y2, ST7571_PAGE_HEIGHT), st7571->nlines);



	switch (format) {

	case DRM_FORMAT_XRGB8888:

		/* Threated as monochrome (R1) */

		fallthrough;

	case DRM_FORMAT_R1:

		x1 = rect->x1;

		x2 = rect->x2;

		x1 = rect->x1 * 1;

		x2 = rect->x2 * 1;

		break;

	case DRM_FORMAT_R2:

		fallthrough;

	case DRM_FORMAT_XRGB8888:

		x1 = rect->x1 * 2;

		x2 = rect->x2 * 2;

		break;
@@ -374,7 +374,7 @@ static int st7571_fb_update_rect_grayscale(struct drm_framebuffer *fb, struct dr 


	for (int y = rect->y1; y < rect->y2; y += ST7571_PAGE_HEIGHT) {

		for (int x = x1; x < x2; x++)

			row[x] = st7571_transform_xy(st7571->hwbuf, x, y);

			row[x] = st7571_transform_xy(st7571->hwbuf, x, y, 2);



		st7571_set_position(st7571, rect->x1, y);
@@ -395,7 +395,7 @@ static int st7571_fb_update_rect_grayscale(struct drm_framebuffer *fb, struct dr 
			 * For monochrome formats, write the same value twice to get

			 * either a black or white pixel.

			 */

			if (format == DRM_FORMAT_R1 || format == DRM_FORMAT_XRGB8888)

			if (format == DRM_FORMAT_R1)

				regmap_bulk_write(st7571->regmap, ST7571_DATA_MODE, row + x, 1);

		}

	}