linux-kernel - [PATCH 4/4] i2c: stm32f7: use proper DMAENGINE API for termination

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Message-ID: <1632151292-18503-5-git-send-email-alain.volmat@foss.st.com>
Date:   Mon, 20 Sep 2021 17:21:32 +0200
From:   Alain Volmat <alain.volmat@...s.st.com>
To:     <wsa@...nel.org>, <pierre-yves.mordret@...s.st.com>
CC:     <alexandre.torgue@...s.st.com>, <linux-i2c@...r.kernel.org>,
        <linux-stm32@...md-mailman.stormreply.com>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-kernel@...r.kernel.org>, <fabrice.gasnier@...s.st.com>,
        <amelie.delaunay@...s.st.com>, <alain.volmat@...s.st.com>
Subject: [PATCH 4/4] i2c: stm32f7: use proper DMAENGINE API for termination

dmaengine_terminate_all() is deprecated in favor of explicitly saying if
it should be sync or async.  Here, we use dmaengine_terminate_sync in
i2c_xfer and i2c_smbus_xfer handlers and rely on
dmaengine_terminate_async within interrupt handlers
(transmission error cases).
dmaengine_synchronize is added within i2c_xfer and i2c_smbus_xfer handler
to finalize terminate started in interrupt handlers.

Signed-off-by: Alain Volmat <alain.volmat@...s.st.com>
---
 drivers/i2c/busses/i2c-stm32f7.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c
index 50d5ae81d227..66145d2b9b55 100644
--- a/drivers/i2c/busses/i2c-stm32f7.c
+++ b/drivers/i2c/busses/i2c-stm32f7.c
@@ -1521,7 +1521,7 @@ static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data)
 		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);
+			dmaengine_terminate_async(dma->chan_using);
 		}
 		f7_msg->result = -ENXIO;
 	}
@@ -1588,7 +1588,7 @@ 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;
 	}
 
@@ -1665,7 +1665,7 @@ 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;
@@ -1702,6 +1702,9 @@ static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap,
 						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
@@ -1716,7 +1719,7 @@ static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap,
 		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;
 	}
@@ -1761,6 +1764,9 @@ static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
 					      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
@@ -1774,7 +1780,7 @@ static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
 	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;
-- 
2.25.1