Commit 833d14a4 authored by Geert Uytterhoeven's avatar Geert Uytterhoeven Committed by Sam Ravnborg
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video: fbdev: ssd1307fb: Cache address ranges 



Cache the column and page ranges, to avoid doing unneeded I2C transfers
when the values haven't changed.

Signed-off-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: default avatarSam Ravnborg <sam@ravnborg.org>
Signed-off-by: default avatarSam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727134730.3765898-6-geert@linux-m68k.org
parent 251e48a1

drivers/video/fbdev/ssd1307fb.c

+25 −2
Original line number Diff line number Diff line
@@ -82,6 +82,11 @@ struct ssd1307fb_par { 
	struct regulator *vbat_reg;

	u32 vcomh;

	u32 width;

	/* Cached address ranges */

	u8 col_start;

	u8 col_end;

	u8 page_start;

	u8 page_end;

};



struct ssd1307fb_array {
@@ -158,6 +163,9 @@ static int ssd1307fb_set_col_range(struct ssd1307fb_par *par, u8 col_start, 
	u8 col_end = col_start + cols - 1;

	int ret;



	if (col_start == par->col_start && col_end == par->col_end)

		return 0;



	ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COL_RANGE);

	if (ret < 0)

		return ret;
@@ -166,7 +174,13 @@ static int ssd1307fb_set_col_range(struct ssd1307fb_par *par, u8 col_start, 
	if (ret < 0)

		return ret;



	return ssd1307fb_write_cmd(par->client, col_end);

	ret = ssd1307fb_write_cmd(par->client, col_end);

	if (ret < 0)

		return ret;



	par->col_start = col_start;

	par->col_end = col_end;

	return 0;

}



static int ssd1307fb_set_page_range(struct ssd1307fb_par *par, u8 page_start,
@@ -175,6 +189,9 @@ static int ssd1307fb_set_page_range(struct ssd1307fb_par *par, u8 page_start, 
	u8 page_end = page_start + pages - 1;

	int ret;



	if (page_start == par->page_start && page_end == par->page_end)

		return 0;



	ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PAGE_RANGE);

	if (ret < 0)

		return ret;
@@ -183,7 +200,13 @@ static int ssd1307fb_set_page_range(struct ssd1307fb_par *par, u8 page_start, 
	if (ret < 0)

		return ret;



	return ssd1307fb_write_cmd(par->client, page_end);

	ret = ssd1307fb_write_cmd(par->client, page_end);

	if (ret < 0)

		return ret;



	par->page_start = page_start;

	par->page_end = page_end;

	return 0;

}



static int ssd1307fb_update_rect(struct ssd1307fb_par *par, unsigned int x,