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Code Issues Releases Wiki Activity

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: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727134730.3765898-6-geert@linux-m68k.org
This commit is contained in:
Geert Uytterhoeven 2021-07-27 15:47:30 +02:00 committed by Sam Ravnborg
parent 251e48a1db
commit 833d14a4bf
1 changed files with 25 additions and 2 deletions
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27
drivers/video/fbdev/ssd1307fb.c
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@ -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,