1 files changed, 69 insertions, 92 deletions

diff --git a/drivers/i2c/busses/i2c-xiic.c b/drivers/i2c/busses/i2c-xiic.c
index bb93db98404e..eb789cfb9973 100644
--- a/drivers/i2c/busses/i2c-xiic.c
+++ b/drivers/i2c/busses/i2c-xiic.c
@@ -23,7 +23,7 @@
 #include <linux/platform_device.h>
 #include <linux/i2c.h>
 #include <linux/interrupt.h>
-#include <linux/wait.h>
+#include <linux/completion.h>
 #include <linux/platform_data/i2c-xiic.h>
 #include <linux/io.h>
 #include <linux/slab.h>
@@ -48,7 +48,7 @@ enum xiic_endian {
  * struct xiic_i2c - Internal representation of the XIIC I2C bus
  * @dev: Pointer to device structure
  * @base: Memory base of the HW registers
- * @wait: Wait queue for callers
+ * @completion:	Completion for callers
  * @adap: Kernel adapter representation
  * @tx_msg: Messages from above to be sent
  * @lock: Mutual exclusion
@@ -64,7 +64,7 @@ enum xiic_endian {
 struct xiic_i2c {
 	struct device *dev;
 	void __iomem *base;
-	wait_queue_head_t wait;
+	struct completion completion;
 	struct i2c_adapter adap;
 	struct i2c_msg *tx_msg;
 	struct mutex lock;
@@ -160,6 +160,9 @@ struct xiic_i2c {
 #define XIIC_PM_TIMEOUT		1000	/* ms */
 /* timeout waiting for the controller to respond */
 #define XIIC_I2C_TIMEOUT	(msecs_to_jiffies(1000))
+/* timeout waiting for the controller finish transfers */
+#define XIIC_XFER_TIMEOUT	(msecs_to_jiffies(10000))
+
 /*
  * The following constant is used for the device global interrupt enable
  * register, to enable all interrupts for the device, this is the only bit
@@ -170,7 +173,7 @@ struct xiic_i2c {
 #define xiic_tx_space(i2c) ((i2c)->tx_msg->len - (i2c)->tx_pos)
 #define xiic_rx_space(i2c) ((i2c)->rx_msg->len - (i2c)->rx_pos)
 
-static int xiic_start_xfer(struct xiic_i2c *i2c);
+static int xiic_start_xfer(struct xiic_i2c *i2c, struct i2c_msg *msgs, int num);
 static void __xiic_start_xfer(struct xiic_i2c *i2c);
 
 /*
@@ -367,7 +370,7 @@ static void xiic_wakeup(struct xiic_i2c *i2c, int code)
 	i2c->rx_msg = NULL;
 	i2c->nmsgs = 0;
 	i2c->state = code;
-	wake_up(&i2c->wait);
+	complete(&i2c->completion);
 }
 
 static irqreturn_t xiic_process(int irq, void *dev_id)
@@ -375,6 +378,9 @@ static irqreturn_t xiic_process(int irq, void *dev_id)
 	struct xiic_i2c *i2c = dev_id;
 	u32 pend, isr, ier;
 	u32 clr = 0;
+	int xfer_more = 0;
+	int wakeup_req = 0;
+	int wakeup_code = 0;
 
 	/* Get the interrupt Status from the IPIF. There is no clearing of
 	 * interrupts in the IPIF. Interrupts must be cleared at the source.
@@ -411,10 +417,14 @@ static irqreturn_t xiic_process(int irq, void *dev_id)
 		 */
 		xiic_reinit(i2c);
 
-		if (i2c->rx_msg)
-			xiic_wakeup(i2c, STATE_ERROR);
-		if (i2c->tx_msg)
-			xiic_wakeup(i2c, STATE_ERROR);
+		if (i2c->rx_msg) {
+			wakeup_req = 1;
+			wakeup_code = STATE_ERROR;
+		}
+		if (i2c->tx_msg) {
+			wakeup_req = 1;
+			wakeup_code = STATE_ERROR;
+		}
 	}
 	if (pend & XIIC_INTR_RX_FULL_MASK) {
 		/* Receive register/FIFO is full */
@@ -448,8 +458,7 @@ static irqreturn_t xiic_process(int irq, void *dev_id)
 				i2c->tx_msg++;
 				dev_dbg(i2c->adap.dev.parent,
 					"%s will start next...\n", __func__);
-
-				__xiic_start_xfer(i2c);
+				xfer_more = 1;
 			}
 		}
 	}
@@ -463,11 +472,13 @@ static irqreturn_t xiic_process(int irq, void *dev_id)
 		if (!i2c->tx_msg)
 			goto out;
 
-		if ((i2c->nmsgs == 1) && !i2c->rx_msg &&
-			xiic_tx_space(i2c) == 0)
-			xiic_wakeup(i2c, STATE_DONE);
+		wakeup_req = 1;
+
+		if (i2c->nmsgs == 1 && !i2c->rx_msg &&
+		    xiic_tx_space(i2c) == 0)
+			wakeup_code = STATE_DONE;
 		else
-			xiic_wakeup(i2c, STATE_ERROR);
+			wakeup_code = STATE_ERROR;
 	}
 	if (pend & (XIIC_INTR_TX_EMPTY_MASK | XIIC_INTR_TX_HALF_MASK)) {
 		/* Transmit register/FIFO is empty or ½ empty */
@@ -491,7 +502,7 @@ static irqreturn_t xiic_process(int irq, void *dev_id)
 			if (i2c->nmsgs > 1) {
 				i2c->nmsgs--;
 				i2c->tx_msg++;
-				__xiic_start_xfer(i2c);
+				xfer_more = 1;
 			} else {
 				xiic_irq_dis(i2c, XIIC_INTR_TX_HALF_MASK);
 
@@ -509,6 +520,13 @@ out:
 	dev_dbg(i2c->adap.dev.parent, "%s clr: 0x%x\n", __func__, clr);
 
 	xiic_setreg32(i2c, XIIC_IISR_OFFSET, clr);
+	if (xfer_more)
+		__xiic_start_xfer(i2c);
+	if (wakeup_req)
+		xiic_wakeup(i2c, wakeup_code);
+
+	WARN_ON(xfer_more && wakeup_req);
+
 	mutex_unlock(&i2c->lock);
 	return IRQ_HANDLED;
 }
@@ -525,7 +543,7 @@ static int xiic_busy(struct xiic_i2c *i2c)
 	int tries = 3;
 	int err;
 
-	if (i2c->tx_msg)
+	if (i2c->tx_msg || i2c->rx_msg)
 		return -EBUSY;
 
 	/* In single master mode bus can only be busy, when in use by this
@@ -554,7 +572,6 @@ static void xiic_start_recv(struct xiic_i2c *i2c)
 {
 	u8 rx_watermark;
 	struct i2c_msg *msg = i2c->rx_msg = i2c->tx_msg;
-	unsigned long flags;
 
 	/* Clear and enable Rx full interrupt. */
 	xiic_irq_clr_en(i2c, XIIC_INTR_RX_FULL_MASK | XIIC_INTR_TX_ERROR_MASK);
@@ -570,7 +587,6 @@ static void xiic_start_recv(struct xiic_i2c *i2c)
 		rx_watermark = IIC_RX_FIFO_DEPTH;
 	xiic_setreg8(i2c, XIIC_RFD_REG_OFFSET, rx_watermark - 1);
 
-	local_irq_save(flags);
 	if (!(msg->flags & I2C_M_NOSTART))
 		/* write the address */
 		xiic_setreg16(i2c, XIIC_DTR_REG_OFFSET,
@@ -580,7 +596,6 @@ static void xiic_start_recv(struct xiic_i2c *i2c)
 
 	xiic_setreg16(i2c, XIIC_DTR_REG_OFFSET,
 		msg->len | ((i2c->nmsgs == 1) ? XIIC_TX_DYN_STOP_MASK : 0));
-	local_irq_restore(flags);
 
 	if (i2c->nmsgs == 1)
 		/* very last, enable bus not busy as well */
@@ -594,8 +609,6 @@ static void xiic_start_send(struct xiic_i2c *i2c)
 {
 	struct i2c_msg *msg = i2c->tx_msg;
 
-	xiic_irq_clr(i2c, XIIC_INTR_TX_ERROR_MASK);
-
 	dev_dbg(i2c->adap.dev.parent, "%s entry, msg: %p, len: %d",
 		__func__, msg, msg->len);
 	dev_dbg(i2c->adap.dev.parent, "%s entry, ISR: 0x%x, CR: 0x%x\n",
@@ -613,36 +626,17 @@ static void xiic_start_send(struct xiic_i2c *i2c)
 		xiic_setreg16(i2c, XIIC_DTR_REG_OFFSET, data);
 	}
 
-	xiic_fill_tx_fifo(i2c);
-
 	/* Clear any pending Tx empty, Tx Error and then enable them. */
 	xiic_irq_clr_en(i2c, XIIC_INTR_TX_EMPTY_MASK | XIIC_INTR_TX_ERROR_MASK |
-		XIIC_INTR_BNB_MASK);
-}
-
-static irqreturn_t xiic_isr(int irq, void *dev_id)
-{
-	struct xiic_i2c *i2c = dev_id;
-	u32 pend, isr, ier;
-	irqreturn_t ret = IRQ_NONE;
-	/* Do not processes a devices interrupts if the device has no
-	 * interrupts pending
-	 */
-
-	dev_dbg(i2c->adap.dev.parent, "%s entry\n", __func__);
-
-	isr = xiic_getreg32(i2c, XIIC_IISR_OFFSET);
-	ier = xiic_getreg32(i2c, XIIC_IIER_OFFSET);
-	pend = isr & ier;
-	if (pend)
-		ret = IRQ_WAKE_THREAD;
+		XIIC_INTR_BNB_MASK |
+		((i2c->nmsgs > 1 || xiic_tx_space(i2c)) ?
+			XIIC_INTR_TX_HALF_MASK : 0));
 
-	return ret;
+	xiic_fill_tx_fifo(i2c);
 }
 
 static void __xiic_start_xfer(struct xiic_i2c *i2c)
 {
-	int first = 1;
 	int fifo_space = xiic_tx_fifo_space(i2c);
 	dev_dbg(i2c->adap.dev.parent, "%s entry, msg: %p, fifos space: %d\n",
 		__func__, i2c->tx_msg, fifo_space);
@@ -653,46 +647,34 @@ static void __xiic_start_xfer(struct xiic_i2c *i2c)
 	i2c->rx_pos = 0;
 	i2c->tx_pos = 0;
 	i2c->state = STATE_START;
-	while ((fifo_space >= 2) && (first || (i2c->nmsgs > 1))) {
-		if (!first) {
-			i2c->nmsgs--;
-			i2c->tx_msg++;
-			i2c->tx_pos = 0;
-		} else
-			first = 0;
-
-		if (i2c->tx_msg->flags & I2C_M_RD) {
-			/* we dont date putting several reads in the FIFO */
-			xiic_start_recv(i2c);
-			return;
-		} else {
-			xiic_start_send(i2c);
-			if (xiic_tx_space(i2c) != 0) {
-				/* the message could not be completely sent */
-				break;
-			}
-		}
-
-		fifo_space = xiic_tx_fifo_space(i2c);
+	if (i2c->tx_msg->flags & I2C_M_RD) {
+		/* we dont date putting several reads in the FIFO */
+		xiic_start_recv(i2c);
+	} else {
+		xiic_start_send(i2c);
 	}
-
-	/* there are more messages or the current one could not be completely
-	 * put into the FIFO, also enable the half empty interrupt
-	 */
-	if (i2c->nmsgs > 1 || xiic_tx_space(i2c))
-		xiic_irq_clr_en(i2c, XIIC_INTR_TX_HALF_MASK);
-
 }
 
-static int xiic_start_xfer(struct xiic_i2c *i2c)
+static int xiic_start_xfer(struct xiic_i2c *i2c, struct i2c_msg *msgs, int num)
 {
 	int ret;
+
 	mutex_lock(&i2c->lock);
 
+	ret = xiic_busy(i2c);
+	if (ret)
+		goto out;
+
+	i2c->tx_msg = msgs;
+	i2c->rx_msg = NULL;
+	i2c->nmsgs = num;
+	init_completion(&i2c->completion);
+
 	ret = xiic_reinit(i2c);
 	if (!ret)
 		__xiic_start_xfer(i2c);
 
+out:
 	mutex_unlock(&i2c->lock);
 
 	return ret;
@@ -710,31 +692,27 @@ static int xiic_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
 	if (err < 0)
 		return err;
 
-	err = xiic_busy(i2c);
-	if (err)
-		goto out;
-
-	i2c->tx_msg = msgs;
-	i2c->nmsgs = num;
-
-	err = xiic_start_xfer(i2c);
+	err = xiic_start_xfer(i2c, msgs, num);
 	if (err < 0) {
 		dev_err(adap->dev.parent, "Error xiic_start_xfer\n");
-		goto out;
+		return err;
 	}
 
-	if (wait_event_timeout(i2c->wait, (i2c->state == STATE_ERROR) ||
-		(i2c->state == STATE_DONE), HZ)) {
-		err = (i2c->state == STATE_DONE) ? num : -EIO;
-		goto out;
-	} else {
+	err = wait_for_completion_timeout(&i2c->completion, XIIC_XFER_TIMEOUT);
+	mutex_lock(&i2c->lock);
+	if (err == 0) {	/* Timeout */
 		i2c->tx_msg = NULL;
 		i2c->rx_msg = NULL;
 		i2c->nmsgs = 0;
 		err = -ETIMEDOUT;
-		goto out;
+	} else if (err < 0) {	/* Completion error */
+		i2c->tx_msg = NULL;
+		i2c->rx_msg = NULL;
+		i2c->nmsgs = 0;
+	} else {
+		err = (i2c->state == STATE_DONE) ? num : -EIO;
 	}
-out:
+	mutex_unlock(&i2c->lock);
 	pm_runtime_mark_last_busy(i2c->dev);
 	pm_runtime_put_autosuspend(i2c->dev);
 	return err;
@@ -795,7 +773,6 @@ static int xiic_i2c_probe(struct platform_device *pdev)
 	i2c->adap.dev.of_node = pdev->dev.of_node;
 
 	mutex_init(&i2c->lock);
-	init_waitqueue_head(&i2c->wait);
 
 	i2c->clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(i2c->clk))
@@ -812,7 +789,7 @@ static int xiic_i2c_probe(struct platform_device *pdev)
 	pm_runtime_use_autosuspend(i2c->dev);
 	pm_runtime_set_active(i2c->dev);
 	pm_runtime_enable(i2c->dev);
-	ret = devm_request_threaded_irq(&pdev->dev, irq, xiic_isr,
+	ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
 					xiic_process, IRQF_ONESHOT,
 					pdev->name, i2c);