diff mbox series

[2/3] i2c: meson: keep peripheral clock enabled

Message ID 20201007080751.1259442-3-jbrunet@baylibre.com
State Accepted
Commit 79e137b1540165f788394658442284d55a858984
Headers show
Series i2c: meson: scl rate fixups | expand

Commit Message

Jerome Brunet Oct. 7, 2020, 8:07 a.m. UTC
SCL rate appears to be different than what is expected. For example,
We get 164kHz on i2c3 of the vim3 when 400kHz is expected. This is
partially due to the peripheral clock being disabled when the clock is
set.

Let's keep the peripheral clock on after probe to fix the problem. This
does not affect the SCL output which is still gated when i2c is idle.

Fixes: 09af1c2fa490 ("i2c: meson: set clock divider in probe instead of setting it for each transfer")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
---
 drivers/i2c/busses/i2c-meson.c | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

Comments

Wolfram Sang Oct. 8, 2020, 10 a.m. UTC | #1
On Wed, Oct 07, 2020 at 10:07:50AM +0200, Jerome Brunet wrote:
> SCL rate appears to be different than what is expected. For example,
> We get 164kHz on i2c3 of the vim3 when 400kHz is expected. This is
> partially due to the peripheral clock being disabled when the clock is
> set.
> 
> Let's keep the peripheral clock on after probe to fix the problem. This
> does not affect the SCL output which is still gated when i2c is idle.
> 
> Fixes: 09af1c2fa490 ("i2c: meson: set clock divider in probe instead of setting it for each transfer")
> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>

Applied to for-current, thanks!
diff mbox series

Patch

diff --git a/drivers/i2c/busses/i2c-meson.c b/drivers/i2c/busses/i2c-meson.c
index dac0d2a00cec..e7ec2ab2a220 100644
--- a/drivers/i2c/busses/i2c-meson.c
+++ b/drivers/i2c/busses/i2c-meson.c
@@ -370,16 +370,12 @@  static int meson_i2c_xfer_messages(struct i2c_adapter *adap,
 	struct meson_i2c *i2c = adap->algo_data;
 	int i, ret = 0;
 
-	clk_enable(i2c->clk);
-
 	for (i = 0; i < num; i++) {
 		ret = meson_i2c_xfer_msg(i2c, msgs + i, i == num - 1, atomic);
 		if (ret)
 			break;
 	}
 
-	clk_disable(i2c->clk);
-
 	return ret ?: i;
 }
 
@@ -448,7 +444,7 @@  static int meson_i2c_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	ret = clk_prepare(i2c->clk);
+	ret = clk_prepare_enable(i2c->clk);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "can't prepare clock\n");
 		return ret;
@@ -470,7 +466,7 @@  static int meson_i2c_probe(struct platform_device *pdev)
 
 	ret = i2c_add_adapter(&i2c->adap);
 	if (ret < 0) {
-		clk_unprepare(i2c->clk);
+		clk_disable_unprepare(i2c->clk);
 		return ret;
 	}
 
@@ -488,7 +484,7 @@  static int meson_i2c_remove(struct platform_device *pdev)
 	struct meson_i2c *i2c = platform_get_drvdata(pdev);
 
 	i2c_del_adapter(&i2c->adap);
-	clk_unprepare(i2c->clk);
+	clk_disable_unprepare(i2c->clk);
 
 	return 0;
 }