---
  drivers/soc/fsl/qe/qmc.c | 175 ++++++++++++++++++++++++++++++++++++---
  1 file changed, 163 insertions(+), 12 deletions(-)

diff --git a/drivers/soc/fsl/qe/qmc.c b/drivers/soc/fsl/qe/qmc.c
index dc113463fbc7..258a34641551 100644
--- a/drivers/soc/fsl/qe/qmc.c
+++ b/drivers/soc/fsl/qe/qmc.c

@@ -177,6 +177,7 @@ struct qmc_chan {
  	struct qmc *qmc;
  	void __iomem *s_param;
  	enum qmc_mode mode;
+	spinlock_t	ts_lock; /* Protect timeslots */
  	u64	tx_ts_mask_avail;
  	u64	tx_ts_mask;
  	u64	rx_ts_mask_avail;

@@ -265,6 +266,7 @@ static inline void qmc_setbits32(void __iomem *addr, u32 set)
  int qmc_chan_get_info(struct qmc_chan *chan, struct qmc_chan_info *info)
  {
  	struct tsa_serial_info tsa_info;
+	unsigned long flags;
  	int ret;
  
  	/* Retrieve info from the TSA related serial */

@@ -272,6 +274,8 @@ int qmc_chan_get_info(struct qmc_chan *chan, struct qmc_chan_info *info)
  	if (ret)
  		return ret;
  
+	spin_lock_irqsave(&chan->ts_lock, flags);
+
  	info->mode = chan->mode;
  	info->rx_fs_rate = tsa_info.rx_fs_rate;
  	info->rx_bit_rate = tsa_info.rx_bit_rate;

@@ -280,6 +284,8 @@ int qmc_chan_get_info(struct qmc_chan *chan, struct qmc_chan_info *info)
  	info->tx_bit_rate = tsa_info.tx_bit_rate;
  	info->nb_rx_ts = hweight64(chan->rx_ts_mask);
  
+	spin_unlock_irqrestore(&chan->ts_lock, flags);
+
  	return 0;
  }
  EXPORT_SYMBOL(qmc_chan_get_info);

@@ -683,6 +689,40 @@ static int qmc_chan_setup_tsa_32tx(struct qmc_chan *chan, const struct tsa_seria
  	return 0;
  }
  
+static int qmc_chan_setup_tsa_tx(struct qmc_chan *chan, bool enable)
+{
+	struct tsa_serial_info info;
+	int ret;
+
+	/* Retrieve info from the TSA related serial */
+	ret = tsa_serial_get_info(chan->qmc->tsa_serial, &info);
+	if (ret)
+		return ret;
+
+	/* Setup entries */
+	if (chan->qmc->is_tsa_64rxtx)
+		return qmc_chan_setup_tsa_64rxtx(chan, &info, enable);
+
+	return qmc_chan_setup_tsa_32tx(chan, &info, enable);
+}
+
+static int qmc_chan_setup_tsa_rx(struct qmc_chan *chan, bool enable)
+{
+	struct tsa_serial_info info;
+	int ret;
+
+	/* Retrieve info from the TSA related serial */
+	ret = tsa_serial_get_info(chan->qmc->tsa_serial, &info);
+	if (ret)
+		return ret;
+
+	/* Setup entries */
+	if (chan->qmc->is_tsa_64rxtx)
+		return qmc_chan_setup_tsa_64rxtx(chan, &info, enable);
+
+	return qmc_chan_setup_tsa_32rx(chan, &info, enable);
+}
+
  static int qmc_chan_setup_tsa(struct qmc_chan *chan, bool enable)
  {
  	struct tsa_serial_info info;

@@ -719,6 +759,12 @@ static int qmc_chan_stop_rx(struct qmc_chan *chan)
  
  	spin_lock_irqsave(&chan->rx_lock, flags);
  
+	if (chan->is_rx_stopped) {
+		/* The channel is already stopped -> simply return ok */
+		ret = 0;
+		goto end;
+	}
+
  	/* Send STOP RECEIVE command */
  	ret = qmc_chan_command(chan, 0x0);
  	if (ret) {

@@ -729,6 +775,15 @@ static int qmc_chan_stop_rx(struct qmc_chan *chan)
  
  	chan->is_rx_stopped = true;
  
+	if (!chan->qmc->is_tsa_64rxtx || chan->is_tx_stopped) {
+		ret = qmc_chan_setup_tsa_rx(chan, false);
+		if (ret) {
+			dev_err(chan->qmc->dev, "chan %u: Disable tsa entries failed (%d)\n",
+				chan->id, ret);
+			goto end;
+		}
+	}
+
  end:
  	spin_unlock_irqrestore(&chan->rx_lock, flags);
  	return ret;

@@ -741,6 +796,12 @@ static int qmc_chan_stop_tx(struct qmc_chan *chan)
  
  	spin_lock_irqsave(&chan->tx_lock, flags);
  
+	if (chan->is_tx_stopped) {
+		/* The channel is already stopped -> simply return ok */
+		ret = 0;
+		goto end;
+	}
+
  	/* Send STOP TRANSMIT command */
  	ret = qmc_chan_command(chan, 0x1);
  	if (ret) {

@@ -751,37 +812,82 @@ static int qmc_chan_stop_tx(struct qmc_chan *chan)
  
  	chan->is_tx_stopped = true;
  
+	if (!chan->qmc->is_tsa_64rxtx || chan->is_rx_stopped) {
+		ret = qmc_chan_setup_tsa_tx(chan, false);
+		if (ret) {
+			dev_err(chan->qmc->dev, "chan %u: Disable tsa entries failed (%d)\n",
+				chan->id, ret);
+			goto end;
+		}
+	}
+
  end:
  	spin_unlock_irqrestore(&chan->tx_lock, flags);
  	return ret;
  }
  
+static int qmc_chan_start_rx(struct qmc_chan *chan);
+
  int qmc_chan_stop(struct qmc_chan *chan, int direction)
  {
-	int ret;
+	bool is_rx_rollback_needed = false;
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&chan->ts_lock, flags);
  
  	if (direction & QMC_CHAN_READ) {
+		is_rx_rollback_needed = !chan->is_rx_stopped;
  		ret = qmc_chan_stop_rx(chan);
  		if (ret)
-			return ret;
+			goto end;
  	}
  
  	if (direction & QMC_CHAN_WRITE) {
  		ret = qmc_chan_stop_tx(chan);
-		if (ret)
-			return ret;
+		if (ret) {
+			/* Restart rx if needed */
+			if (is_rx_rollback_needed)
+				qmc_chan_start_rx(chan);
+			goto end;
+		}
  	}
  
-	return 0;
+end:
+	spin_unlock_irqrestore(&chan->ts_lock, flags);
+	return ret;
  }
  EXPORT_SYMBOL(qmc_chan_stop);
  
-static void qmc_chan_start_rx(struct qmc_chan *chan)
+static int qmc_setup_chan_trnsync(struct qmc *qmc, struct qmc_chan *chan);
+
+static int qmc_chan_start_rx(struct qmc_chan *chan)
  {
  	unsigned long flags;
+	int ret;
  
  	spin_lock_irqsave(&chan->rx_lock, flags);
  
+	if (!chan->is_rx_stopped) {
+		/* The channel is already started -> simply return ok */
+		ret = 0;
+		goto end;
+	}
+
+	ret = qmc_chan_setup_tsa_rx(chan, true);
+	if (ret) {
+		dev_err(chan->qmc->dev, "chan %u: Enable tsa entries failed (%d)\n",
+			chan->id, ret);
+		goto end;
+	}
+
+	ret = qmc_setup_chan_trnsync(chan->qmc, chan);
+	if (ret) {
+		dev_err(chan->qmc->dev, "chan %u: setup TRNSYNC failed (%d)\n",
+			chan->id, ret);
+		goto end;
+	}
+
  	/* Restart the receiver */
  	if (chan->mode == QMC_TRANSPARENT)
  		qmc_write32(chan->s_param + QMC_SPE_ZDSTATE, 0x18000080);

@@ -792,15 +898,38 @@ static void qmc_chan_start_rx(struct qmc_chan *chan)
  
  	chan->is_rx_stopped = false;
  
+end:
  	spin_unlock_irqrestore(&chan->rx_lock, flags);
+	return ret;
  }
  
-static void qmc_chan_start_tx(struct qmc_chan *chan)
+static int qmc_chan_start_tx(struct qmc_chan *chan)
  {
  	unsigned long flags;
+	int ret;
  
  	spin_lock_irqsave(&chan->tx_lock, flags);
  
+	if (!chan->is_tx_stopped) {
+		/* The channel is already started -> simply return ok */
+		ret = 0;
+		goto end;
+	}
+
+	ret = qmc_chan_setup_tsa_tx(chan, true);
+	if (ret) {
+		dev_err(chan->qmc->dev, "chan %u: Enable tsa entries failed (%d)\n",
+			chan->id, ret);
+		goto end;
+	}
+
+	ret = qmc_setup_chan_trnsync(chan->qmc, chan);
+	if (ret) {
+		dev_err(chan->qmc->dev, "chan %u: setup TRNSYNC failed (%d)\n",
+			chan->id, ret);
+		goto end;
+	}
+
  	/*
  	 * Enable channel transmitter as it could be disabled if
  	 * qmc_chan_reset() was called.

@@ -812,18 +941,39 @@ static void qmc_chan_start_tx(struct qmc_chan *chan)
  
  	chan->is_tx_stopped = false;
  
+end:
  	spin_unlock_irqrestore(&chan->tx_lock, flags);
+	return ret;
  }
  
  int qmc_chan_start(struct qmc_chan *chan, int direction)
  {
-	if (direction & QMC_CHAN_READ)
-		qmc_chan_start_rx(chan);
+	bool is_rx_rollback_needed = false;
+	unsigned long flags;
+	int ret = 0;
  
-	if (direction & QMC_CHAN_WRITE)
-		qmc_chan_start_tx(chan);
+	spin_lock_irqsave(&chan->ts_lock, flags);
  
-	return 0;
+	if (direction & QMC_CHAN_READ) {
+		is_rx_rollback_needed = chan->is_rx_stopped;
+		ret = qmc_chan_start_rx(chan);
+		if (ret)
+			goto end;
+	}
+
+	if (direction & QMC_CHAN_WRITE) {
+		ret = qmc_chan_start_tx(chan);
+		if (ret) {
+			/* Restop rx if needed */
+			if (is_rx_rollback_needed)
+				qmc_chan_stop_rx(chan);
+			goto end;
+		}
+	}
+
+end:
+	spin_unlock_irqrestore(&chan->ts_lock, flags);
+	return ret;
  }
  EXPORT_SYMBOL(qmc_chan_start);
  

@@ -992,6 +1142,7 @@ static int qmc_of_parse_chans(struct qmc *qmc, struct device_node *np)
  		}
  
  		chan->id = chan_id;
+		spin_lock_init(&chan->ts_lock);
  		spin_lock_init(&chan->rx_lock);
  		spin_lock_init(&chan->tx_lock);