openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

i2c: meson: keep peripheral clock enabled 

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: 09af1c2fa4 ("i2c: meson: set clock divider in probe instead of setting it for each transfer")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
This commit is contained in:
Jerome Brunet 2020-10-07 10:07:50 +02:00 committed by Wolfram Sang
parent 28683e847e
commit 79e137b154
1 changed files with 3 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
drivers/i2c/busses/i2c-meson.c
View File

@ -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;
}