diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-stm32f7.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-stm32f7.c | 31 |
1 files changed, 28 insertions, 3 deletions
diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c index a7977eef2ead..0f0c41174ddd 100644 --- a/drivers/i2c/busses/i2c-stm32f7.c +++ b/drivers/i2c/busses/i2c-stm32f7.c @@ -1394,6 +1394,7 @@ static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data) { 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; @@ -1418,6 +1419,10 @@ static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data) 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; } @@ -1433,7 +1438,7 @@ static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data) /* 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; @@ -1446,7 +1451,7 @@ static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data) 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); @@ -1586,12 +1591,23 @@ static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap, time_left = wait_for_completion_timeout(&i2c_dev->complete, i2c_dev->adap.timeout); ret = f7_msg->result; + if (ret) { + /* + * It is possible that some unsent data have already been + * written into TXDR. To avoid sending old data in a + * further transfer, flush TXDR in case of any error + */ + writel_relaxed(STM32F7_I2C_ISR_TXE, + i2c_dev->base + STM32F7_I2C_ISR); + goto pm_free; + } if (!time_left) { dev_dbg(i2c_dev->dev, "Access to slave 0x%x timed out\n", i2c_dev->msg->addr); if (i2c_dev->use_dma) dmaengine_terminate_all(dma->chan_using); + stm32f7_i2c_wait_free_bus(i2c_dev); ret = -ETIMEDOUT; } @@ -1634,13 +1650,22 @@ static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, timeout = wait_for_completion_timeout(&i2c_dev->complete, i2c_dev->adap.timeout); ret = f7_msg->result; - if (ret) + if (ret) { + /* + * It is possible that some unsent data have already been + * written into TXDR. To avoid sending old data in a + * further transfer, flush TXDR in case of any error + */ + writel_relaxed(STM32F7_I2C_ISR_TXE, + i2c_dev->base + STM32F7_I2C_ISR); goto pm_free; + } if (!timeout) { 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; } |