From mboxrd@z Thu Jan 1 00:00:00 1970 From: nicola@corna.info (Nicola Corna) Date: Thu, 29 Oct 2015 12:34:25 +0100 Subject: [PATCH v2 3/5] i2c: add I2C_AQ_NO_CLK_STRETCH to i2c-bcm2835.c In-Reply-To: <1446118467-26453-1-git-send-email-nicola@corna.info> References: <1445976718-7449-1-git-send-email-nicola@corna.info> <1446118467-26453-1-git-send-email-nicola@corna.info> Message-ID: <1446118467-26453-3-git-send-email-nicola@corna.info> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 --- drivers/i2c/busses/i2c-bcm2835.c | 5 +++++ 1 file changed, 5 insertions(+) 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); -- 2.6.1