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| author | Arnaud Patard (Rtp) <arnaud.patard@rtp-net.org> | 2010-07-15 15:06:14 +0200 |
|---|---|---|
| committer | Ben Dooks <ben-linux@fluff.org> | 2010-10-21 23:43:27 +0100 |
| commit | d2360b8e845ce0e142e72697a504ee9372421dc3 (patch) | |
| tree | 36d8af296af35099cf5bea8c0f36bb613260278d | |
| parent | f6f94e2ab1b33f0082ac22d71f66385a60d8157f (diff) | |
| download | linux-stable-d2360b8e845ce0e142e72697a504ee9372421dc3.tar.gz linux-stable-d2360b8e845ce0e142e72697a504ee9372421dc3.tar.bz2 linux-stable-d2360b8e845ce0e142e72697a504ee9372421dc3.zip | |
i2c-s3c2410: Enable i2c clock only when doing some transfert
This patch modify the s3c2410 i2c driver behaviour to enable the
i2c clock only when needed. I'm not sure if this has a big impact
on power usage but at least it's fixing a bug with the uda1380
codec which needs to be hard reset'ed if the i2c clock is enabled
before it's powered on (at least on h1940).
Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
| -rw-r--r-- | drivers/i2c/busses/i2c-s3c2410.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c index bf831bf81587..3dc1eb9f8088 100644 --- a/drivers/i2c/busses/i2c-s3c2410.c +++ b/drivers/i2c/busses/i2c-s3c2410.c @@ -555,18 +555,23 @@ static int s3c24xx_i2c_xfer(struct i2c_adapter *adap, int retry; int ret; + clk_enable(i2c->clk); + for (retry = 0; retry < adap->retries; retry++) { ret = s3c24xx_i2c_doxfer(i2c, msgs, num); - if (ret != -EAGAIN) + if (ret != -EAGAIN) { + clk_disable(i2c->clk); return ret; + } dev_dbg(i2c->dev, "Retrying transmission (%d)\n", retry); udelay(100); } + clk_disable(i2c->clk); return -EREMOTEIO; } @@ -911,6 +916,7 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev) platform_set_drvdata(pdev, i2c); dev_info(&pdev->dev, "%s: S3C I2C adapter\n", dev_name(&i2c->adap.dev)); + clk_disable(i2c->clk); return 0; err_cpufreq: @@ -978,7 +984,9 @@ static int s3c24xx_i2c_resume(struct device *dev) struct s3c24xx_i2c *i2c = platform_get_drvdata(pdev); i2c->suspended = 0; + clk_enable(i2c->clk); s3c24xx_i2c_init(i2c); + clk_disable(i2c->clk); return 0; } |