From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Maxime Ripard <mripard@kernel.org>,
David Airlie <airlied@linux.ie>, Daniel Vetter <daniel@ffwll.ch>
Cc: linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org,
linux-kernel@vger.kernel.org,
Geert Uytterhoeven <geert@linux-m68k.org>
Subject: [PATCH 5/5] video: fbdev: ssd1307fb: Cache address ranges
Date: Tue, 18 May 2021 10:28:09 +0200 [thread overview]
Message-ID: <20210518082809.1467549-6-geert@linux-m68k.org> (raw)
In-Reply-To: <20210518082809.1467549-1-geert@linux-m68k.org>
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>
---
drivers/video/fbdev/ssd1307fb.c | 52 +++++++++++++++++++++++----------
1 file changed, 36 insertions(+), 16 deletions(-)
diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c
index 8e3d4be74723b9bf..23b43ce479898813 100644
--- a/drivers/video/fbdev/ssd1307fb.c
+++ b/drivers/video/fbdev/ssd1307fb.c
@@ -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 {
@@ -160,28 +165,43 @@ static int ssd1307fb_set_address_range(struct ssd1307fb_par *par, u8 col_start,
int ret;
/* Set column range */
- ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COL_RANGE);
- if (ret < 0)
- return ret;
+ if (col_start != par->col_start || col_end != par->col_end) {
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COL_RANGE);
+ if (ret < 0)
+ return ret;
- ret = ssd1307fb_write_cmd(par->client, col_start);
- if (ret < 0)
- return ret;
+ ret = ssd1307fb_write_cmd(par->client, col_start);
+ if (ret < 0)
+ return ret;
- ret = ssd1307fb_write_cmd(par->client, col_end);
- if (ret < 0)
- return ret;
+ ret = ssd1307fb_write_cmd(par->client, col_end);
+ if (ret < 0)
+ return ret;
+
+ par->col_start = col_start;
+ par->col_end = col_end;
+ }
/* Set page range */
- ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PAGE_RANGE);
- if (ret < 0)
- return ret;
+ if (page_start != par->page_start || page_end != par->page_end) {
+ ret = ssd1307fb_write_cmd(par->client,
+ SSD1307FB_SET_PAGE_RANGE);
+ if (ret < 0)
+ return ret;
- ret = ssd1307fb_write_cmd(par->client, page_start);
- if (ret < 0)
- return ret;
+ ret = ssd1307fb_write_cmd(par->client, page_start);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd1307fb_write_cmd(par->client, page_end);
+ if (ret < 0)
+ return ret;
- return ssd1307fb_write_cmd(par->client, page_end);
+ par->page_start = page_start;
+ par->page_end = page_end;
+ }
+
+ return 0;
}
static int ssd1307fb_update_rect(struct ssd1307fb_par *par, unsigned int x,
--
2.25.1
prev parent reply other threads:[~2021-05-18 9:06 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-18 8:28 [PATCH 0/5] video: fbdev: ssd1307fb: Optimizations and improvements Geert Uytterhoeven
2021-05-18 8:28 ` [PATCH 1/5] video: fbdev: ssd1307fb: Propagate errors via ssd1307fb_update_display() Geert Uytterhoeven
2021-05-18 8:28 ` [PATCH 2/5] video: fbdev: ssd1307fb: Simplify ssd1307fb_update_display() Geert Uytterhoeven
2021-05-18 8:28 ` [PATCH 3/5] video: fbdev: ssd1307fb: Extract ssd1307fb_set_address_range() Geert Uytterhoeven
2021-05-18 8:28 ` [PATCH 4/5] video: fbdev: ssd1307fb: Optimize screen updates Geert Uytterhoeven
2021-05-18 8:28 ` Geert Uytterhoeven [this message]
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