From: Alain Volmat alain.volmat@foss.st.com
commit 31b90a95ccbbb4b628578ac17e3b3cc8eeacfe31 upstream.
In case of receiving a NACK, the dma transfer should be stopped to avoid feeding data into the FIFO. Also ensure to properly return the proper error code and avoid waiting for the end of the dma completion in case of error happening during the transmission.
Fixes: 7ecc8cfde553 ("i2c: i2c-stm32f7: Add DMA support") 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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/i2c/busses/i2c-stm32f7.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)
--- a/drivers/i2c/busses/i2c-stm32f7.c +++ b/drivers/i2c/busses/i2c-stm32f7.c @@ -1379,6 +1379,7 @@ static irqreturn_t stm32f7_i2c_isr_event { struct stm32f7_i2c_dev *i2c_dev = data; struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; + struct stm32_i2c_dma *dma = i2c_dev->dma; void __iomem *base = i2c_dev->base; u32 status, mask; int ret = IRQ_HANDLED; @@ -1403,6 +1404,10 @@ static irqreturn_t stm32f7_i2c_isr_event if (status & STM32F7_I2C_ISR_NACKF) { dev_dbg(i2c_dev->dev, "<%s>: Receive NACK\n", __func__); writel_relaxed(STM32F7_I2C_ICR_NACKCF, base + STM32F7_I2C_ICR); + if (i2c_dev->use_dma) { + stm32f7_i2c_disable_dma_req(i2c_dev); + dmaengine_terminate_all(dma->chan_using); + } f7_msg->result = -ENXIO; }
@@ -1418,7 +1423,7 @@ static irqreturn_t stm32f7_i2c_isr_event /* Clear STOP flag */ writel_relaxed(STM32F7_I2C_ICR_STOPCF, base + STM32F7_I2C_ICR);
- if (i2c_dev->use_dma) { + if (i2c_dev->use_dma && !f7_msg->result) { ret = IRQ_WAKE_THREAD; } else { i2c_dev->master_mode = false; @@ -1431,7 +1436,7 @@ static irqreturn_t stm32f7_i2c_isr_event if (f7_msg->stop) { mask = STM32F7_I2C_CR2_STOP; stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask); - } else if (i2c_dev->use_dma) { + } else if (i2c_dev->use_dma && !f7_msg->result) { ret = IRQ_WAKE_THREAD; } else if (f7_msg->smbus) { stm32f7_i2c_smbus_rep_start(i2c_dev);