Merge branch 'for-linus/i2c/2636-rc8' of git://git.fluff.org/bjdooks/linux

torvalds · torvalds · commit f68c834b045a · 2010-10-18T13:05:10.000-07:00
* 'for-linus/i2c/2636-rc8' of git://git.fluff.org/bjdooks/linux:
  i2c-imx: do not allow interruptions when waiting for I2C to complete
  i2c-davinci: Fix TX setup for more SoCs
diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
@@ -331,21 +331,16 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop)
 	INIT_COMPLETION(dev->cmd_complete);
 	dev->cmd_err = 0;
 
-	/* Take I2C out of reset, configure it as master and set the
-	 * start bit */
-	flag = DAVINCI_I2C_MDR_IRS | DAVINCI_I2C_MDR_MST | DAVINCI_I2C_MDR_STT;
+	/* Take I2C out of reset and configure it as master */
+	flag = DAVINCI_I2C_MDR_IRS | DAVINCI_I2C_MDR_MST;
 
 	/* if the slave address is ten bit address, enable XA bit */
 	if (msg->flags & I2C_M_TEN)
 		flag |= DAVINCI_I2C_MDR_XA;
 	if (!(msg->flags & I2C_M_RD))
 		flag |= DAVINCI_I2C_MDR_TRX;
-	if (stop)
-		flag |= DAVINCI_I2C_MDR_STP;
-	if (msg->len == 0) {
+	if (msg->len == 0)
 		flag |= DAVINCI_I2C_MDR_RM;
-		flag &= ~DAVINCI_I2C_MDR_STP;
-	}
 
 	/* Enable receive or transmit interrupts */
 	w = davinci_i2c_read_reg(dev, DAVINCI_I2C_IMR_REG);
@@ -357,18 +352,29 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop)
 
 	dev->terminate = 0;
 
+	/*
+	 * Write mode register first as needed for correct behaviour
+	 * on OMAP-L138, but don't set STT yet to avoid a race with XRDY
+	 * occuring before we have loaded DXR
+	 */
+	davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag);
+
 	/*
 	 * First byte should be set here, not after interrupt,
 	 * because transmit-data-ready interrupt can come before
 	 * NACK-interrupt during sending of previous message and
 	 * ICDXR may have wrong data
+	 * It also saves us one interrupt, slightly faster
 	 */
 	if ((!(msg->flags & I2C_M_RD)) && dev->buf_len) {
 		davinci_i2c_write_reg(dev, DAVINCI_I2C_DXR_REG, *dev->buf++);
 		dev->buf_len--;
 	}
 
-	/* write the data into mode register; start transmitting */
+	/* Set STT to begin transmit now DXR is loaded */
+	flag |= DAVINCI_I2C_MDR_STT;
+	if (stop && msg->len != 0)
+		flag |= DAVINCI_I2C_MDR_STP;
 	davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag);
 
 	r = wait_for_completion_interruptible_timeout(&dev->cmd_complete,
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
@@ -159,15 +159,9 @@ static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy)
 
 static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx)
 {
-	int result;
-
-	result = wait_event_interruptible_timeout(i2c_imx->queue,
-		i2c_imx->i2csr & I2SR_IIF, HZ / 10);
+	wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10);
 
-	if (unlikely(result < 0)) {
-		dev_dbg(&i2c_imx->adapter.dev, "<%s> result < 0\n", __func__);
-		return result;
-	} else if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) {
+	if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) {
 		dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__);
 		return -ETIMEDOUT;
 	}
@@ -295,7 +289,7 @@ static irqreturn_t i2c_imx_isr(int irq, void *dev_id)
 		i2c_imx->i2csr = temp;
 		temp &= ~I2SR_IIF;
 		writeb(temp, i2c_imx->base + IMX_I2C_I2SR);
-		wake_up_interruptible(&i2c_imx->queue);
+		wake_up(&i2c_imx->queue);
 		return IRQ_HANDLED;
 	}
 
