1 files changed, 40 insertions, 19 deletions

diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c
index b9b19a2a2ffa..6d4aa64b195d 100644
--- a/drivers/i2c/busses/i2c-stm32f7.c
+++ b/drivers/i2c/busses/i2c-stm32f7.c
@@ -828,18 +828,14 @@ static void stm32f7_i2c_smbus_reload(struct stm32f7_i2c_dev *i2c_dev)
 	writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2);
 }
 
-static int stm32f7_i2c_release_bus(struct i2c_adapter *i2c_adap)
+static void stm32f7_i2c_release_bus(struct i2c_adapter *i2c_adap)
 {
 	struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
 
-	dev_info(i2c_dev->dev, "Trying to recover bus\n");
-
 	stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1,
 			     STM32F7_I2C_CR1_PE);
 
 	stm32f7_i2c_hw_config(i2c_dev);
-
-	return 0;
 }
 
 static int stm32f7_i2c_wait_free_bus(struct stm32f7_i2c_dev *i2c_dev)
@@ -854,13 +850,7 @@ static int stm32f7_i2c_wait_free_bus(struct stm32f7_i2c_dev *i2c_dev)
 	if (!ret)
 		return 0;
 
-	dev_info(i2c_dev->dev, "bus busy\n");
-
-	ret = stm32f7_i2c_release_bus(&i2c_dev->adap);
-	if (ret) {
-		dev_err(i2c_dev->dev, "Failed to recover the bus (%d)\n", ret);
-		return ret;
-	}
+	stm32f7_i2c_release_bus(&i2c_dev->adap);
 
 	return -EBUSY;
 }
@@ -1493,6 +1483,7 @@ 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;
@@ -1518,6 +1509,10 @@ static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data)
 		dev_dbg(i2c_dev->dev, "<%s>: Receive NACK (addr %x)\n",
 			__func__, f7_msg->addr);
 		writel_relaxed(STM32F7_I2C_ICR_NACKCF, base + STM32F7_I2C_ICR);
+		if (i2c_dev->use_dma) {
+			stm32f7_i2c_disable_dma_req(i2c_dev);
+			dmaengine_terminate_async(dma->chan_using);
+		}
 		f7_msg->result = -ENXIO;
 	}
 
@@ -1533,7 +1528,7 @@ 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;
@@ -1546,7 +1541,7 @@ 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);
@@ -1583,7 +1578,7 @@ static irqreturn_t stm32f7_i2c_isr_event_thread(int irq, void *data)
 	if (!ret) {
 		dev_dbg(i2c_dev->dev, "<%s>: Timed out\n", __func__);
 		stm32f7_i2c_disable_dma_req(i2c_dev);
-		dmaengine_terminate_all(dma->chan_using);
+		dmaengine_terminate_async(dma->chan_using);
 		f7_msg->result = -ETIMEDOUT;
 	}
 
@@ -1660,7 +1655,7 @@ static irqreturn_t stm32f7_i2c_isr_error(int irq, void *data)
 	/* Disable dma */
 	if (i2c_dev->use_dma) {
 		stm32f7_i2c_disable_dma_req(i2c_dev);
-		dmaengine_terminate_all(dma->chan_using);
+		dmaengine_terminate_async(dma->chan_using);
 	}
 
 	i2c_dev->master_mode = false;
@@ -1696,12 +1691,26 @@ 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) {
+		if (i2c_dev->use_dma)
+			dmaengine_synchronize(dma->chan_using);
+
+		/*
+		 * 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);
+			dmaengine_terminate_sync(dma->chan_using);
+		stm32f7_i2c_wait_free_bus(i2c_dev);
 		ret = -ETIMEDOUT;
 	}
 
@@ -1744,13 +1753,25 @@ 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) {
+		if (i2c_dev->use_dma)
+			dmaengine_synchronize(dma->chan_using);
+
+		/*
+		 * 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);
+			dmaengine_terminate_sync(dma->chan_using);
+		stm32f7_i2c_wait_free_bus(i2c_dev);
 		ret = -ETIMEDOUT;
 		goto pm_free;
 	}