The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From b933d1faf8fa30d16171bcff404e39c41b2a7c84 Mon Sep 17 00:00:00 2001

From: Alain Volmat alain.volmat@foss.st.com Date: Mon, 20 Sep 2021 17:21:30 +0200 Subject: [PATCH] i2c: stm32f7: recover the bus on access timeout

When getting an access timeout, ensure that the bus is in a proper state prior to returning the error.

Fixes: aeb068c57214 ("i2c: i2c-stm32f7: add driver") Signed-off-by: Alain Volmat alain.volmat@foss.st.com Reviewed-by: Pierre-Yves MORDRET pierre-yves.mordret@foss.st.com Signed-off-by: Wolfram Sang wsa@kernel.org

diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c index ed977b6f7ab6..ad3459a3bc5e 100644 --- a/drivers/i2c/busses/i2c-stm32f7.c +++ b/drivers/i2c/busses/i2c-stm32f7.c @@ -1712,6 +1712,7 @@ static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap, i2c_dev->msg->addr); if (i2c_dev->use_dma) dmaengine_terminate_all(dma->chan_using); + stm32f7_i2c_wait_free_bus(i2c_dev); ret = -ETIMEDOUT; }

@@ -1769,6 +1770,7 @@ static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, dev_dbg(dev, "Access to slave 0x%x timed out\n", f7_msg->addr); if (i2c_dev->use_dma) dmaengine_terminate_all(dma->chan_using); + stm32f7_i2c_wait_free_bus(i2c_dev); ret = -ETIMEDOUT; goto pm_free; }