Message ID | 1446118467-26453-3-git-send-email-nicola@corna.info (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
On Thu, Oct 29, 2015 at 12:34:25PM +0100, Nicola Corna wrote: > As reported here > http://www.advamation.com/knowhow/raspberrypi/rpi-i2c-bug.html > and confirmed here > https://www.raspberrypi.org/forums/viewtopic.php?p=146272 > the BCM2835 has a hardware bug in its i2c module which prevents a correct > clock stretching. This patch adds the I2C_AQ_NO_CLK_STRETCH quirk flag > to i2c-bcm2835. > > Signed-off-by: Nicola Corna <nicola@corna.info> I put the above links into the code as comments, reworded the commit message a little and applied it to for-next, thanks!
diff --git a/drivers/i2c/busses/i2c-bcm2835.c b/drivers/i2c/busses/i2c-bcm2835.c index 3032b89..38d7102 100644 --- a/drivers/i2c/busses/i2c-bcm2835.c +++ b/drivers/i2c/busses/i2c-bcm2835.c @@ -222,6 +222,10 @@ static const struct i2c_algorithm bcm2835_i2c_algo = { .functionality = bcm2835_i2c_func, }; +static const struct i2c_adapter_quirks bcm2835_i2c_quirks = { + .flags = I2C_AQ_NO_CLK_STRETCH, +}; + static int bcm2835_i2c_probe(struct platform_device *pdev) { struct bcm2835_i2c_dev *i2c_dev; @@ -293,6 +297,7 @@ static int bcm2835_i2c_probe(struct platform_device *pdev) adap->algo = &bcm2835_i2c_algo; adap->dev.parent = &pdev->dev; adap->dev.of_node = pdev->dev.of_node; + adap->quirks = &bcm2835_i2c_quirks; bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, 0);
As reported here http://www.advamation.com/knowhow/raspberrypi/rpi-i2c-bug.html and confirmed here https://www.raspberrypi.org/forums/viewtopic.php?p=146272 the BCM2835 has a hardware bug in its i2c module which prevents a correct clock stretching. This patch adds the I2C_AQ_NO_CLK_STRETCH quirk flag to i2c-bcm2835. Signed-off-by: Nicola Corna <nicola@corna.info> --- drivers/i2c/busses/i2c-bcm2835.c | 5 +++++ 1 file changed, 5 insertions(+)