I2C big cleanup

index 5d19a49..2d9b03c 100644
@@ -943,7 +943,7 @@ omap_i2c_probe(struct platform_device *pdev)
 {
 	struct omap_i2c_dev	*dev;
 	struct i2c_adapter	*adap;
-	struct resource		*mem, *irq, *ioarea;
+	struct resource		*mem, *irq;
 	struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data;
 	struct device_node	*node = pdev->dev.of_node;
 	const struct of_device_id *match;

@@ -962,17 +962,16 @@ omap_i2c_probe(struct platform_device *pdev)
 		return -ENODEV;
 	}
 
-	ioarea = request_mem_region(mem->start, resource_size(mem),
-			pdev->name);
-	if (!ioarea) {
-		dev_err(&pdev->dev, "I2C region already claimed\n");
-		return -EBUSY;
+	dev = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL);
+	if (!dev) {
+		dev_err(&pdev->dev, "Menory allocation failed\n");
+		return -ENOMEM;
 	}
 
-	dev = kzalloc(sizeof(struct omap_i2c_dev), GFP_KERNEL);
-	if (!dev) {
-		r = -ENOMEM;
-		goto err_release_region;
+	dev->base = devm_request_and_ioremap(&pdev->dev, mem);
+	if (!dev->base) {
+		dev_err(&pdev->dev, "I2C region already claimed\n");
+		return -ENOMEM;
 	}
 
 	match = of_match_device(of_match_ptr(omap_i2c_of_match), &pdev->dev);

@@ -995,11 +994,6 @@ omap_i2c_probe(struct platform_device *pdev)
 
 	dev->dev = &pdev->dev;
 	dev->irq = irq->start;
-	dev->base = ioremap(mem->start, resource_size(mem));
-	if (!dev->base) {
-		r = -ENOMEM;
-		goto err_free_mem;
-	}
 
 	platform_set_drvdata(pdev, dev);
 	init_completion(&dev->cmd_complete);

@@ -1057,7 +1051,8 @@ omap_i2c_probe(struct platform_device *pdev)
 
 	isr = (dev->rev < OMAP_I2C_OMAP1_REV_2) ? omap_i2c_omap1_isr :
 								   omap_i2c_isr;
-	r = request_irq(dev->irq, isr, IRQF_NO_SUSPEND, pdev->name, dev);
+	r = devm_request_irq(&pdev->dev, dev->irq, isr, IRQF_NO_SUSPEND,
+			     pdev->name, dev);
 
 	if (r) {
 		dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);

@@ -1081,7 +1076,7 @@ omap_i2c_probe(struct platform_device *pdev)
 	r = i2c_add_numbered_adapter(adap);
 	if (r) {
 		dev_err(dev->dev, "failure adding adapter\n");
-		goto err_free_irq;
+		goto err_unuse_clocks;
 	}
 
 	of_i2c_register_devices(adap);

@@ -1090,18 +1085,12 @@ omap_i2c_probe(struct platform_device *pdev)
 
 	return 0;
 
-err_free_irq:
-	free_irq(dev->irq, dev);
 err_unuse_clocks:
 	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 	pm_runtime_put(dev->dev);
-	iounmap(dev->base);
 	pm_runtime_disable(&pdev->dev);
 err_free_mem:
 	platform_set_drvdata(pdev, NULL);
-	kfree(dev);
-err_release_region:
-	release_mem_region(mem->start, resource_size(mem));
 
 	return r;
 }

@@ -1109,12 +1098,10 @@ err_release_region:
 static int __devexit omap_i2c_remove(struct platform_device *pdev)
 {
 	struct omap_i2c_dev	*dev = platform_get_drvdata(pdev);
-	struct resource		*mem;
 	int ret;
 
 	platform_set_drvdata(pdev, NULL);
 
-	free_irq(dev->irq, dev);
 	i2c_del_adapter(&dev->adapter);
 	ret = pm_runtime_get_sync(&pdev->dev);
 	if (IS_ERR_VALUE(ret))

@@ -1123,10 +1110,6 @@ static int __devexit omap_i2c_remove(struct platform_device *pdev)
 	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 	pm_runtime_put(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
-	iounmap(dev->base);
-	kfree(dev);
-	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	release_mem_region(mem->start, resource_size(mem));
 	return 0;
 }
 

index 2d9b03c..236cb38 100644
@@ -812,8 +812,7 @@ complete:
 							OMAP_I2C_BUFSTAT_REG)
 							>> 8) & 0x3F;
 			}
-			while (num_bytes) {
-				num_bytes--;
+			while (num_bytes--) {
 				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
 				if (dev->buf_len) {
 					*dev->buf++ = w;

@@ -855,8 +854,7 @@ complete:
 							OMAP_I2C_BUFSTAT_REG)
 							& 0x3F;
 			}
-			while (num_bytes) {
-				num_bytes--;
+			while (num_bytes--) {
 				w = 0;
 				if (dev->buf_len) {
 					w = *dev->buf++;

index 236cb38..0dd647a 100644
@@ -813,22 +813,7 @@ complete:
 							>> 8) & 0x3F;
 			}
 			while (num_bytes--) {
-				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
-				if (dev->buf_len) {
-					*dev->buf++ = w;
-					dev->buf_len--;
-					/*
-					 * Data reg in 2430, omap3 and
-					 * omap4 is 8 bit wide
-					 */
-					if (dev->flags &
-						 OMAP_I2C_FLAG_16BIT_DATA_REG) {
-						if (dev->buf_len) {
-							*dev->buf++ = w >> 8;
-							dev->buf_len--;
-						}
-					}
-				} else {
+				if (!dev->buf_len) {
 					if (stat & OMAP_I2C_STAT_RRDY)
 						dev_err(dev->dev,
 							"RRDY IRQ while no data"

@@ -839,6 +824,21 @@ complete:
 								" requested\n");
 					break;
 				}
+
+				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
+				*dev->buf++ = w;
+				dev->buf_len--;
+				/*
+				 * Data reg in 2430, omap3 and
+				 * omap4 is 8 bit wide
+				 */
+				if (dev->flags &
+						OMAP_I2C_FLAG_16BIT_DATA_REG) {
+					if (dev->buf_len) {
+						*dev->buf++ = w >> 8;
+						dev->buf_len--;
+					}
+				}
 			}
 			omap_i2c_ack_stat(dev,
 				stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));

@@ -855,22 +855,7 @@ complete:
 							& 0x3F;
 			}
 			while (num_bytes--) {
-				w = 0;
-				if (dev->buf_len) {
-					w = *dev->buf++;
-					dev->buf_len--;
-					/*
-					 * Data reg in 2430, omap3 and
-					 * omap4 is 8 bit wide
-					 */
-					if (dev->flags &
-						 OMAP_I2C_FLAG_16BIT_DATA_REG) {
-						if (dev->buf_len) {
-							w |= *dev->buf++ << 8;
-							dev->buf_len--;
-						}
-					}
-				} else {
+				if (!dev->buf_len) {
 					if (stat & OMAP_I2C_STAT_XRDY)
 						dev_err(dev->dev,
 							"XRDY IRQ while no "

@@ -882,6 +867,20 @@ complete:
 					break;
 				}
 
+				w = *dev->buf++;
+				dev->buf_len--;
+				/*
+				 * Data reg in 2430, omap3 and
+				 * omap4 is 8 bit wide
+				 */
+				if (dev->flags &
+						OMAP_I2C_FLAG_16BIT_DATA_REG) {
+					if (dev->buf_len) {
+						w |= *dev->buf++ << 8;
+						dev->buf_len--;
+					}
+				}
+
 				if ((dev->errata & I2C_OMAP_ERRATA_I462) &&
 				    errata_omap3_i462(dev, &stat, &err))
 					goto complete;

index 0dd647a..30ea63c 100644
@@ -786,6 +786,7 @@ complete:
 			dev_err(dev->dev, "Arbitration lost\n");
 			err |= OMAP_I2C_STAT_AL;
 		}
+
 		/*
 		 * ProDB0017052: Clear ARDY bit twice
 		 */

@@ -798,6 +799,7 @@ complete:
 			omap_i2c_complete_cmd(dev, err);
 			return IRQ_HANDLED;
 		}
+
 		if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
 			u8 num_bytes = 1;
 

@@ -844,6 +846,7 @@ complete:
 				stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));
 			continue;
 		}
+
 		if (stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)) {
 			u8 num_bytes = 1;
 			if (dev->fifo_size) {

@@ -891,10 +894,12 @@ complete:
 				stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
 			continue;
 		}
+
 		if (stat & OMAP_I2C_STAT_ROVR) {
 			dev_err(dev->dev, "Receive overrun\n");
 			dev->cmd_err |= OMAP_I2C_STAT_ROVR;
 		}
+
 		if (stat & OMAP_I2C_STAT_XUDF) {
 			dev_err(dev->dev, "Transmit underflow\n");
 			dev->cmd_err |= OMAP_I2C_STAT_XUDF;

index 30ea63c..f24eae9 100644
@@ -731,7 +731,7 @@ static int errata_omap3_i462(struct omap_i2c_dev *dev, u16 *stat, int *err)
 
 	while (--timeout && !(*stat & OMAP_I2C_STAT_XUDF)) {
 		if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
-			omap_i2c_ack_stat(dev, *stat & (OMAP_I2C_STAT_XRDY |
+			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
 							OMAP_I2C_STAT_XDR));
 			return -ETIMEDOUT;
 		}

@@ -792,10 +792,11 @@ complete:
 		 */
 		if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
 					OMAP_I2C_STAT_AL)) {
-			omap_i2c_ack_stat(dev, stat &
-				(OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
-				OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR |
-				OMAP_I2C_STAT_ARDY));
+			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
+						OMAP_I2C_STAT_RDR |
+						OMAP_I2C_STAT_XRDY |
+						OMAP_I2C_STAT_XDR |
+						OMAP_I2C_STAT_ARDY));
 			omap_i2c_complete_cmd(dev, err);
 			return IRQ_HANDLED;
 		}

@@ -842,8 +843,8 @@ complete:
 					}
 				}
 			}
-			omap_i2c_ack_stat(dev,
-				stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));
+			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
+						OMAP_I2C_STAT_RDR));
 			continue;
 		}
 

@@ -890,8 +891,8 @@ complete:
 
 				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 			}
-			omap_i2c_ack_stat(dev,
-				stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
+			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
+						OMAP_I2C_STAT_XDR));
 			continue;
 		}
 

index f24eae9..815577b 100644
@@ -801,36 +801,62 @@ complete:
 			return IRQ_HANDLED;
 		}
 
-		if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
+		if (stat & OMAP_I2C_STAT_RDR) {
 			u8 num_bytes = 1;
 
+			if (dev->fifo_size)
+				num_bytes = dev->buf_len;
+
+			while (num_bytes--) {
+				if (!dev->buf_len) {
+					dev_err(dev->dev,
+							"RDR IRQ while no data"
+							" requested\n");
+					break;
+				}
+
+				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
+				*dev->buf++ = w;
+				dev->buf_len--;
+
+				/*
+				 * Data reg in 2430, omap3 and
+				 * omap4 is 8 bit wide
+				 */
+				if (dev->flags &
+						OMAP_I2C_FLAG_16BIT_DATA_REG) {
+					if (dev->buf_len) {
+						*dev->buf++ = w >> 8;
+						dev->buf_len--;
+					}
+				}
+			}
+
 			if (dev->errata & I2C_OMAP_ERRATA_I207)
 				i2c_omap_errata_i207(dev, stat);
 
-			if (dev->fifo_size) {
-				if (stat & OMAP_I2C_STAT_RRDY)
-					num_bytes = dev->fifo_size;
-				else    /* read RXSTAT on RDR interrupt */
-					num_bytes = (omap_i2c_read_reg(dev,
-							OMAP_I2C_BUFSTAT_REG)
-							>> 8) & 0x3F;
-			}
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
+			continue;
+		}
+
+		if (stat & OMAP_I2C_STAT_RRDY) {
+			u8 num_bytes = 1;
+
+			if (dev->fifo_size)
+				num_bytes = dev->fifo_size;
+
 			while (num_bytes--) {
 				if (!dev->buf_len) {
-					if (stat & OMAP_I2C_STAT_RRDY)
-						dev_err(dev->dev,
+					dev_err(dev->dev,
 							"RRDY IRQ while no data"
-								" requested\n");
-					if (stat & OMAP_I2C_STAT_RDR)
-						dev_err(dev->dev,
-							"RDR IRQ while no data"
-								" requested\n");
+							" requested\n");
 					break;
 				}
 
 				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
 				*dev->buf++ = w;
 				dev->buf_len--;
+
 				/*
 				 * Data reg in 2430, omap3 and
 				 * omap4 is 8 bit wide

@@ -843,36 +869,68 @@ complete:
 					}
 				}
 			}
-			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
-						OMAP_I2C_STAT_RDR));
+
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY);
 			continue;
 		}
 
-		if (stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)) {
+		if (stat & OMAP_I2C_STAT_XDR) {
 			u8 num_bytes = 1;
-			if (dev->fifo_size) {
-				if (stat & OMAP_I2C_STAT_XRDY)
-					num_bytes = dev->fifo_size;
-				else    /* read TXSTAT on XDR interrupt */
-					num_bytes = omap_i2c_read_reg(dev,
-							OMAP_I2C_BUFSTAT_REG)
-							& 0x3F;
+
+			if (dev->fifo_size)
+				num_bytes = dev->buf_len;
+
+			while (num_bytes--) {
+				if (!dev->buf_len) {
+					dev_err(dev->dev,
+							"XDR IRQ while no "
+							"data to send\n");
+					break;
+				}
+
+				w = *dev->buf++;
+				dev->buf_len--;
+
+				/*
+				 * Data reg in 2430, omap3 and
+				 * omap4 is 8 bit wide
+				 */
+				if (dev->flags &
+						OMAP_I2C_FLAG_16BIT_DATA_REG) {
+					if (dev->buf_len) {
+						w |= *dev->buf++ << 8;
+						dev->buf_len--;
+					}
+				}
+
+				if ((dev->errata & I2C_OMAP_ERRATA_I462) &&
+				    errata_omap3_i462(dev, &stat, &err))
+					goto complete;
+
+				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 			}
+
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
+			continue;
+		}
+
+		if (stat & OMAP_I2C_STAT_XRDY) {
+			u8 num_bytes = 1;
+
+			if (dev->fifo_size)
+				num_bytes = dev->fifo_size;
+
 			while (num_bytes--) {
 				if (!dev->buf_len) {
-					if (stat & OMAP_I2C_STAT_XRDY)
-						dev_err(dev->dev,
+					dev_err(dev->dev,
 							"XRDY IRQ while no "
 							"data to send\n");
-					if (stat & OMAP_I2C_STAT_XDR)
-						dev_err(dev->dev,
-							"XDR IRQ while no "
-							"data to send\n");
 					break;
 				}
 
 				w = *dev->buf++;
 				dev->buf_len--;
+
 				/*
 				 * Data reg in 2430, omap3 and
 				 * omap4 is 8 bit wide

@@ -891,8 +949,8 @@ complete:
 
 				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 			}
-			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
-						OMAP_I2C_STAT_XDR));
+
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
 			continue;
 		}
 

index 815577b..fb57221 100644
@@ -725,27 +725,30 @@ omap_i2c_omap1_isr(int this_irq, void *dev_id)
  * data to DATA_REG. Otherwise some data bytes can be lost while transferring
  * them from the memory to the I2C interface.
  */
-static int errata_omap3_i462(struct omap_i2c_dev *dev, u16 *stat, int *err)
+static int errata_omap3_i462(struct omap_i2c_dev *dev)
 {
 	unsigned long timeout = 10000;
+	u16 stat;
 
-	while (--timeout && !(*stat & OMAP_I2C_STAT_XUDF)) {
-		if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
+	do {
+		stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+		if (stat & OMAP_I2C_STAT_XUDF)
+			break;
+
+		if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
 			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
 							OMAP_I2C_STAT_XDR));
-			return -ETIMEDOUT;
+			return -EIO;
 		}
 
 		cpu_relax();
-		*stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
-	}
+	} while (--timeout);
 
 	if (!timeout) {
 		dev_err(dev->dev, "timeout waiting on XUDF bit\n");
 		return 0;
 	}
 
-	*err |= OMAP_I2C_STAT_XUDF;
 	return 0;
 }
 

@@ -903,9 +906,16 @@ complete:
 					}
 				}
 
-				if ((dev->errata & I2C_OMAP_ERRATA_I462) &&
-				    errata_omap3_i462(dev, &stat, &err))
-					goto complete;
+				if (dev->errata & I2C_OMAP_ERRATA_I462) {
+					int ret;
+
+					ret = errata_omap3_i462(dev);
+					stat = omap_i2c_read_reg(dev,
+							OMAP_I2C_STAT_REG);
+
+					if (ret < 0)
+						goto complete;
+				}
 
 				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 			}

@@ -943,9 +953,16 @@ complete:
 					}
 				}
 
-				if ((dev->errata & I2C_OMAP_ERRATA_I462) &&
-				    errata_omap3_i462(dev, &stat, &err))
-					goto complete;
+				if (dev->errata & I2C_OMAP_ERRATA_I462) {
+					int ret;
+
+					ret = errata_omap3_i462(dev);
+					stat = omap_i2c_read_reg(dev,
+							OMAP_I2C_STAT_REG);
+
+					if (ret < 0)
+						goto complete;
+				}
 
 				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 			}

index fb57221..2c7d7cc 100644
@@ -752,12 +752,81 @@ static int errata_omap3_i462(struct omap_i2c_dev *dev)
 	return 0;
 }
 
+static void omap_i2c_receive_data(struct omap_i2c_dev *dev, u8 num_bytes,
+		bool is_rdr)
+{
+	u16		w;
+
+	while (num_bytes--) {
+		if (!dev->buf_len) {
+			dev_err(dev->dev, "%s without data",
+					is_rdr ? "RDR" : "RRDY");
+			break;
+		}
+
+		w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
+		*dev->buf++ = w;
+		dev->buf_len--;
+
+		/*
+		 * Data reg in 2430, omap3 and
+		 * omap4 is 8 bit wide
+		 */
+		if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
+			if (dev->buf_len) {
+				*dev->buf++ = w >> 8;
+				dev->buf_len--;
+			}
+		}
+	}
+}
+
+static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes,
+		bool is_xdr)
+{
+	u16		w;
+
+	while (num_bytes--) {
+		if (!dev->buf_len) {
+			dev_err(dev->dev, "%s without data",
+					is_xdr ? "XDR" : "XRDY");
+			break;
+		}
+
+		w = *dev->buf++;
+		dev->buf_len--;
+
+		/*
+		 * Data reg in 2430, omap3 and
+		 * omap4 is 8 bit wide
+		 */
+		if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
+			if (dev->buf_len) {
+				w |= *dev->buf++ << 8;
+				dev->buf_len--;
+			}
+		}
+
+		if (dev->errata & I2C_OMAP_ERRATA_I462) {
+			int ret;
+
+			ret = errata_omap3_i462(dev);
+			if (ret < 0)
+				return ret;
+		}
+
+		omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
+	}
+
+	return 0;
+}
+
 static irqreturn_t
 omap_i2c_isr(int this_irq, void *dev_id)
 {
 	struct omap_i2c_dev *dev = dev_id;
 	u16 bits;
-	u16 stat, w;
+	u16 stat;
 	int err, count = 0;
 
 	if (pm_runtime_suspended(dev->dev))

@@ -810,30 +879,7 @@ complete:
 			if (dev->fifo_size)
 				num_bytes = dev->buf_len;
 
-			while (num_bytes--) {
-				if (!dev->buf_len) {
-					dev_err(dev->dev,
-							"RDR IRQ while no data"
-							" requested\n");
-					break;
-				}
-
-				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
-				*dev->buf++ = w;
-				dev->buf_len--;
-
-				/*
-				 * Data reg in 2430, omap3 and
-				 * omap4 is 8 bit wide
-				 */
-				if (dev->flags &
-						OMAP_I2C_FLAG_16BIT_DATA_REG) {
-					if (dev->buf_len) {
-						*dev->buf++ = w >> 8;
-						dev->buf_len--;
-					}
-				}
-			}
+			omap_i2c_receive_data(dev, num_bytes, true);
 
 			if (dev->errata & I2C_OMAP_ERRATA_I207)
 				i2c_omap_errata_i207(dev, stat);

@@ -848,77 +894,22 @@ complete:
 			if (dev->fifo_size)
 				num_bytes = dev->fifo_size;
 
-			while (num_bytes--) {
-				if (!dev->buf_len) {
-					dev_err(dev->dev,
-							"RRDY IRQ while no data"
-							" requested\n");
-					break;
-				}
-
-				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
-				*dev->buf++ = w;
-				dev->buf_len--;
-
-				/*
-				 * Data reg in 2430, omap3 and
-				 * omap4 is 8 bit wide
-				 */
-				if (dev->flags &
-						OMAP_I2C_FLAG_16BIT_DATA_REG) {
-					if (dev->buf_len) {
-						*dev->buf++ = w >> 8;
-						dev->buf_len--;
-					}
-				}
-			}
-
+			omap_i2c_receive_data(dev, num_bytes, false);
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY);
 			continue;
 		}
 
 		if (stat & OMAP_I2C_STAT_XDR) {
 			u8 num_bytes = 1;
+			int ret;
 
 			if (dev->fifo_size)
 				num_bytes = dev->buf_len;
 
-			while (num_bytes--) {
-				if (!dev->buf_len) {
-					dev_err(dev->dev,
-							"XDR IRQ while no "
-							"data to send\n");
-					break;
-				}
-
-				w = *dev->buf++;
-				dev->buf_len--;
-
-				/*
-				 * Data reg in 2430, omap3 and
-				 * omap4 is 8 bit wide
-				 */
-				if (dev->flags &
-						OMAP_I2C_FLAG_16BIT_DATA_REG) {
-					if (dev->buf_len) {
-						w |= *dev->buf++ << 8;
-						dev->buf_len--;
-					}
-				}
-
-				if (dev->errata & I2C_OMAP_ERRATA_I462) {
-					int ret;
-
-					ret = errata_omap3_i462(dev);
-					stat = omap_i2c_read_reg(dev,
-							OMAP_I2C_STAT_REG);
-
-					if (ret < 0)
-						goto complete;
-				}
-
-				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
-			}
+			ret = omap_i2c_transmit_data(dev, num_bytes, true);
+			stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+			if (ret < 0)
+				goto complete;
 
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
 			continue;

@@ -926,46 +917,15 @@ complete:
 
 		if (stat & OMAP_I2C_STAT_XRDY) {
 			u8 num_bytes = 1;
+			int ret;
 
 			if (dev->fifo_size)
 				num_bytes = dev->fifo_size;
 
-			while (num_bytes--) {
-				if (!dev->buf_len) {
-					dev_err(dev->dev,
-							"XRDY IRQ while no "
-							"data to send\n");
-					break;
-				}
-
-				w = *dev->buf++;
-				dev->buf_len--;
-
-				/*
-				 * Data reg in 2430, omap3 and
-				 * omap4 is 8 bit wide
-				 */
-				if (dev->flags &
-						OMAP_I2C_FLAG_16BIT_DATA_REG) {
-					if (dev->buf_len) {
-						w |= *dev->buf++ << 8;
-						dev->buf_len--;
-					}
-				}
-
-				if (dev->errata & I2C_OMAP_ERRATA_I462) {
-					int ret;
-
-					ret = errata_omap3_i462(dev);
-					stat = omap_i2c_read_reg(dev,
-							OMAP_I2C_STAT_REG);
-
-					if (ret < 0)
-						goto complete;
-				}
-
-				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
-			}
+			ret = omap_i2c_transmit_data(dev, num_bytes, false);
+			stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+			if (ret < 0)
+				goto complete;
 
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
 			continue;

index 2c7d7cc..4045134 100644
@@ -827,20 +827,28 @@ omap_i2c_isr(int this_irq, void *dev_id)
 	struct omap_i2c_dev *dev = dev_id;
 	u16 bits;
 	u16 stat;
-	int err, count = 0;
+	int err = 0, count = 0;
 
 	if (pm_runtime_suspended(dev->dev))
 		return IRQ_NONE;
 
-	bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
-	while ((stat = (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG))) & bits) {
+	do {
+		bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
+		stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+		stat &= bits;
+
+		if (!stat) {
+			/* my work here is done */
+			return IRQ_HANDLED;
+		}
+
 		dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
 		if (count++ == 100) {
 			dev_warn(dev->dev, "Too much work in one IRQ\n");
-			break;
+			omap_i2c_complete_cmd(dev, err);
+			return IRQ_HANDLED;
 		}
 
-		err = 0;
 complete:
 		/*
 		 * Ack the stat in one go, but [R/X]DR and [R/X]RDY should be

@@ -940,7 +948,7 @@ complete:
 			dev_err(dev->dev, "Transmit underflow\n");
 			dev->cmd_err |= OMAP_I2C_STAT_XUDF;
 		}
-	}
+	} while (stat);
 
 	return count ? IRQ_HANDLED : IRQ_NONE;
 }

index 4045134..bac1f11 100644
@@ -850,21 +850,19 @@ omap_i2c_isr(int this_irq, void *dev_id)
 		}
 
 complete:
-		/*
-		 * Ack the stat in one go, but [R/X]DR and [R/X]RDY should be
-		 * acked after the data operation is complete.
-		 * Ref: TRM SWPU114Q Figure 18-31
-		 */
-		omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat &
-				~(OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
-				OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
-
-		if (stat & OMAP_I2C_STAT_NACK)
+		if (stat & OMAP_I2C_STAT_NACK) {
 			err |= OMAP_I2C_STAT_NACK;
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
+			omap_i2c_complete_cmd(dev, err);
+			return IRQ_HANDLED;
+		}
 
 		if (stat & OMAP_I2C_STAT_AL) {
 			dev_err(dev->dev, "Arbitration lost\n");
 			err |= OMAP_I2C_STAT_AL;
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_AL);
+			omap_i2c_complete_cmd(dev, err);
+			return IRQ_HANDLED;
 		}
 
 		/*

@@ -941,12 +939,18 @@ complete:
 
 		if (stat & OMAP_I2C_STAT_ROVR) {
 			dev_err(dev->dev, "Receive overrun\n");
-			dev->cmd_err |= OMAP_I2C_STAT_ROVR;
+			err |= OMAP_I2C_STAT_ROVR;
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ROVR);
+			omap_i2c_complete_cmd(dev, err);
+			return IRQ_HANDLED;
 		}
 
 		if (stat & OMAP_I2C_STAT_XUDF) {
 			dev_err(dev->dev, "Transmit underflow\n");
-			dev->cmd_err |= OMAP_I2C_STAT_XUDF;
+			err |= OMAP_I2C_STAT_XUDF;
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XUDF);
+			omap_i2c_complete_cmd(dev, err);
+			return IRQ_HANDLED;
 		}
 	} while (stat);
 

index bac1f11..0da8169 100644
@@ -993,11 +993,12 @@ omap_i2c_probe(struct platform_device *pdev)
 {
 	struct omap_i2c_dev	*dev;
 	struct i2c_adapter	*adap;
-	struct resource		*mem, *irq;
+	struct resource		*mem;
 	struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data;
 	struct device_node	*node = pdev->dev.of_node;
 	const struct of_device_id *match;
 	irq_handler_t isr;
+	int irq;
 	int r;
 
 	/* NOTE: driver uses the static register mapping */

@@ -1006,10 +1007,11 @@ omap_i2c_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "no mem resource?\n");
 		return -ENODEV;
 	}
-	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-	if (!irq) {
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
 		dev_err(&pdev->dev, "no irq resource?\n");
-		return -ENODEV;
+		return irq;
 	}
 
 	dev = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL);

@@ -1043,7 +1045,7 @@ omap_i2c_probe(struct platform_device *pdev)
 	}
 
 	dev->dev = &pdev->dev;
-	dev->irq = irq->start;
+	dev->irq = irq;
 
 	platform_set_drvdata(pdev, dev);
 	init_completion(&dev->cmd_complete);

index 0da8169..3be147a 100644
@@ -199,6 +199,7 @@ struct omap_i2c_dev {
 						 */
 	u8			rev;
 	unsigned		b_hw:1;		/* bad h/w fixes */
+	unsigned		receiver:1;	/* true when we're in receiver mode */
 	u16			iestate;	/* Saved interrupt register */
 	u16			pscstate;
 	u16			scllstate;

@@ -492,6 +493,7 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 
 	INIT_COMPLETION(dev->cmd_complete);
 	dev->cmd_err = 0;
+	dev->receiver = !!(msg->flags & I2C_M_RD);
 
 	w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
 

@@ -837,6 +839,12 @@ omap_i2c_isr(int this_irq, void *dev_id)
 		stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 		stat &= bits;
 
+		/* If we're in receiver mode, ignore XDR/XRDY */
+		if (dev->receiver)
+			stat &= ~(OMAP_I2C_STAT_XDR | OMAP_I2C_STAT_XRDY);
+		else
+			stat &= ~(OMAP_I2C_STAT_RDR | OMAP_I2C_STAT_RRDY);
+
 		if (!stat) {
 			/* my work here is done */
 			return IRQ_HANDLED;

index 3be147a..7918e48 100644
@@ -1095,9 +1095,7 @@ omap_i2c_probe(struct platform_device *pdev)
 
 		dev->fifo_size = (dev->fifo_size / 2);
 
-		if (dev->rev >= OMAP_I2C_REV_ON_3630_4430)
-			dev->b_hw = 0; /* Disable hardware fixes */
-		else
+		if (dev->rev < OMAP_I2C_REV_ON_3630_4430)
 			dev->b_hw = 1; /* Enable hardware fixes */
 
 		/* calculate wakeup latency constraint for MPU */

index 7918e48..96fd528 100644
@@ -962,7 +962,7 @@ complete:
 		}
 	} while (stat);
 
-	return count ? IRQ_HANDLED : IRQ_NONE;
+	return IRQ_HANDLED;
 }
 
 static const struct i2c_algorithm omap_i2c_algo = {

index 96fd528..4af123f 100644
@@ -853,24 +853,21 @@ omap_i2c_isr(int this_irq, void *dev_id)
 		dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
 		if (count++ == 100) {
 			dev_warn(dev->dev, "Too much work in one IRQ\n");
-			omap_i2c_complete_cmd(dev, err);
-			return IRQ_HANDLED;
+			goto out;
 		}
 
 complete:
 		if (stat & OMAP_I2C_STAT_NACK) {
 			err |= OMAP_I2C_STAT_NACK;
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
-			omap_i2c_complete_cmd(dev, err);
-			return IRQ_HANDLED;
+			goto out;
 		}
 
 		if (stat & OMAP_I2C_STAT_AL) {
 			dev_err(dev->dev, "Arbitration lost\n");
 			err |= OMAP_I2C_STAT_AL;
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_AL);
-			omap_i2c_complete_cmd(dev, err);
-			return IRQ_HANDLED;
+			goto out;
 		}
 
 		/*

@@ -883,8 +880,7 @@ complete:
 						OMAP_I2C_STAT_XRDY |
 						OMAP_I2C_STAT_XDR |
 						OMAP_I2C_STAT_ARDY));
-			omap_i2c_complete_cmd(dev, err);
-			return IRQ_HANDLED;
+			goto out;
 		}
 
 		if (stat & OMAP_I2C_STAT_RDR) {

@@ -949,19 +945,19 @@ complete:
 			dev_err(dev->dev, "Receive overrun\n");
 			err |= OMAP_I2C_STAT_ROVR;
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ROVR);
-			omap_i2c_complete_cmd(dev, err);
-			return IRQ_HANDLED;
+			goto out;
 		}
 
 		if (stat & OMAP_I2C_STAT_XUDF) {
 			dev_err(dev->dev, "Transmit underflow\n");
 			err |= OMAP_I2C_STAT_XUDF;
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XUDF);
-			omap_i2c_complete_cmd(dev, err);
-			return IRQ_HANDLED;
+			goto out;
 		}
 	} while (stat);
 
+out:
+	omap_i2c_complete_cmd(dev, err);
 	return IRQ_HANDLED;
 }
 

index 4af123f..f33bc5a 100644
@@ -193,6 +193,7 @@ struct omap_i2c_dev {
 	u8			*regs;
 	size_t			buf_len;
 	struct i2c_adapter	adapter;
+	u8			threshold;
 	u8			fifo_size;	/* use as flag and value
 						 * fifo_size==0 implies no fifo
 						 * if set, should be trsh+1

@@ -418,13 +419,6 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
 	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
 	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
 
-	if (dev->fifo_size) {
-		/* Note: setup required fifo size - 1. RTRSH and XTRSH */
-		buf = (dev->fifo_size - 1) << 8 | OMAP_I2C_BUF_RXFIF_CLR |
-			(dev->fifo_size - 1) | OMAP_I2C_BUF_TXFIF_CLR;
-		omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
-	}
-
 	/* Take the I2C module out of reset: */
 	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
 

@@ -462,6 +456,45 @@ static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
 	return 0;
 }
 
+static void omap_i2c_resize_fifo(struct omap_i2c_dev *dev, u8 size, bool is_rx)
+{
+	u16		buf;
+
+	if (dev->flags & OMAP_I2C_FLAG_NO_FIFO)
+		return;
+
+	/*
+	 * Set up notification threshold based on message size. We're doing
+	 * this to try and avoid draining feature as much as possible. Whenever
+	 * we have big messages to transfer (bigger than our total fifo size)
+	 * then we might use draining feature to transfer the remaining bytes.
+	 */
+
+	dev->threshold = clamp(size, (u8) 1, dev->fifo_size);
+
+	buf = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
+
+	if (is_rx) {
+		/* Clear RX Threshold */
+		buf &= ~(0x3f << 8);
+		buf |= ((dev->threshold - 1) << 8) | OMAP_I2C_BUF_RXFIF_CLR;
+	} else {
+		/* Clear TX Threshold */
+		buf &= ~0x3f;
+		buf |= (dev->threshold - 1) | OMAP_I2C_BUF_TXFIF_CLR;
+	}
+
+	omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
+
+	if (dev->rev < OMAP_I2C_REV_ON_3630_4430)
+		dev->b_hw = 1; /* Enable hardware fixes */
+
+	/* calculate wakeup latency constraint for MPU */
+	if (dev->set_mpu_wkup_lat != NULL)
+		dev->latency = (1000000 * dev->threshold) /
+			(1000 * dev->speed / 8);
+}
+
 /*
  * Low level master read/write transaction.
  */

@@ -478,6 +511,9 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 	if (msg->len == 0)
 		return -EINVAL;
 
+	dev->receiver = !!(msg->flags & I2C_M_RD);
+	omap_i2c_resize_fifo(dev, msg->len, dev->receiver);
+
 	omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
 
 	/* REVISIT: Could the STB bit of I2C_CON be used with probing? */

@@ -493,7 +529,6 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 
 	INIT_COMPLETION(dev->cmd_complete);
 	dev->cmd_err = 0;
-	dev->receiver = !!(msg->flags & I2C_M_RD);
 
 	w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
 

@@ -760,12 +795,6 @@ static void omap_i2c_receive_data(struct omap_i2c_dev *dev, u8 num_bytes,
 	u16		w;
 
 	while (num_bytes--) {
-		if (!dev->buf_len) {
-			dev_err(dev->dev, "%s without data",
-					is_rdr ? "RDR" : "RRDY");
-			break;
-		}
-
 		w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
 		*dev->buf++ = w;
 		dev->buf_len--;

@@ -775,10 +804,8 @@ static void omap_i2c_receive_data(struct omap_i2c_dev *dev, u8 num_bytes,
 		 * omap4 is 8 bit wide
 		 */
 		if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
-			if (dev->buf_len) {
-				*dev->buf++ = w >> 8;
-				dev->buf_len--;
-			}
+			*dev->buf++ = w >> 8;
+			dev->buf_len--;
 		}
 	}
 }

@@ -789,12 +816,6 @@ static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes,
 	u16		w;
 
 	while (num_bytes--) {
-		if (!dev->buf_len) {
-			dev_err(dev->dev, "%s without data",
-					is_xdr ? "XDR" : "XRDY");
-			break;
-		}
-
 		w = *dev->buf++;
 		dev->buf_len--;
 

@@ -803,10 +824,8 @@ static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes,
 		 * omap4 is 8 bit wide
 		 */
 		if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
-			if (dev->buf_len) {
-				w |= *dev->buf++ << 8;
-				dev->buf_len--;
-			}
+			w |= *dev->buf++ << 8;
+			dev->buf_len--;
 		}
 
 		if (dev->errata & I2C_OMAP_ERRATA_I462) {

@@ -901,8 +920,8 @@ complete:
 		if (stat & OMAP_I2C_STAT_RRDY) {
 			u8 num_bytes = 1;
 
-			if (dev->fifo_size)
-				num_bytes = dev->fifo_size;
+			if (dev->threshold)
+				num_bytes = dev->threshold;
 
 			omap_i2c_receive_data(dev, num_bytes, false);
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY);

@@ -929,8 +948,8 @@ complete:
 			u8 num_bytes = 1;
 			int ret;
 
-			if (dev->fifo_size)
-				num_bytes = dev->fifo_size;
+			if (dev->threshold)
+				num_bytes = dev->threshold;
 
 			ret = omap_i2c_transmit_data(dev, num_bytes, false);
 			stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);

index f33bc5a..5d4bad4 100644
@@ -775,6 +775,17 @@ static int errata_omap3_i462(struct omap_i2c_dev *dev)
 		if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
 			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
 							OMAP_I2C_STAT_XDR));
+			if (stat & OMAP_I2C_STAT_NACK) {
+				dev->cmd_err |= OMAP_I2C_STAT_NACK;
+				omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
+			}
+
+			if (stat & OMAP_I2C_STAT_AL) {
+				dev_err(dev->dev, "Arbitration lost\n");
+				dev->cmd_err |= OMAP_I2C_STAT_AL;
+				omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
+			}
+
 			return -EIO;
 		}
 

@@ -875,7 +886,6 @@ omap_i2c_isr(int this_irq, void *dev_id)
 			goto out;
 		}
 
-complete:
 		if (stat & OMAP_I2C_STAT_NACK) {
 			err |= OMAP_I2C_STAT_NACK;
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);

@@ -938,7 +948,7 @@ complete:
 			ret = omap_i2c_transmit_data(dev, num_bytes, true);
 			stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 			if (ret < 0)
-				goto complete;
+				goto out;
 
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
 			continue;

@@ -954,7 +964,7 @@ complete:
 			ret = omap_i2c_transmit_data(dev, num_bytes, false);
 			stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 			if (ret < 0)
-				goto complete;
+				goto out;
 
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
 			continue;

index 5d4bad4..498a462 100644
@@ -946,7 +946,6 @@ omap_i2c_isr(int this_irq, void *dev_id)
 				num_bytes = dev->buf_len;
 
 			ret = omap_i2c_transmit_data(dev, num_bytes, true);
-			stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 			if (ret < 0)
 				goto out;
 

@@ -962,7 +961,6 @@ omap_i2c_isr(int this_irq, void *dev_id)
 				num_bytes = dev->threshold;
 
 			ret = omap_i2c_transmit_data(dev, num_bytes, false);
-			stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 			if (ret < 0)
 				goto out;
 

index 498a462..4a696bd 100644
@@ -862,7 +862,7 @@ omap_i2c_isr(int this_irq, void *dev_id)
 	int err = 0, count = 0;
 
 	if (pm_runtime_suspended(dev->dev))
-		return IRQ_NONE;
+		return IRQ_HANDLED;
 
 	do {
 		bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);

index 4a696bd..e391370 100644
@@ -176,6 +176,7 @@ enum {
 #define I2C_OMAP_ERRATA_I462		(1 << 1)
 
 struct omap_i2c_dev {
+	spinlock_t		lock;		/* IRQ synchronization */
 	struct device		*dev;
 	void __iomem		*base;		/* virtual */
 	int			irq;

@@ -854,9 +855,30 @@ static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes,
 }
 
 static irqreturn_t
-omap_i2c_isr(int this_irq, void *dev_id)
+omap_i2c_isr(int irq, void *dev_id)
 {
 	struct omap_i2c_dev *dev = dev_id;
+	irqreturn_t ret = IRQ_HANDLED;
+	u16 mask;
+	u16 stat;
+
+	spin_lock(&dev->lock);
+	mask = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
+	stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+
+	if (stat & mask)
+		ret = IRQ_WAKE_THREAD;
+
+	spin_unlock(&dev->lock);
+
+	return ret;
+}
+
+static irqreturn_t
+omap_i2c_isr_thread(int this_irq, void *dev_id)
+{
+	struct omap_i2c_dev *dev = dev_id;
+	unsigned long flags;
 	u16 bits;
 	u16 stat;
 	int err = 0, count = 0;

@@ -864,6 +886,7 @@ omap_i2c_isr(int this_irq, void *dev_id)
 	if (pm_runtime_suspended(dev->dev))
 		return IRQ_HANDLED;
 
+	spin_lock_irqsave(&dev->lock, flags);
 	do {
 		bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
 		stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);

@@ -877,6 +900,7 @@ omap_i2c_isr(int this_irq, void *dev_id)
 
 		if (!stat) {
 			/* my work here is done */
+			spin_unlock_irqrestore(&dev->lock, flags);
 			return IRQ_HANDLED;
 		}
 

@@ -985,6 +1009,8 @@ omap_i2c_isr(int this_irq, void *dev_id)
 
 out:
 	omap_i2c_complete_cmd(dev, err);
+	spin_unlock_irqrestore(&dev->lock, flags);
+
 	return IRQ_HANDLED;
 }
 

@@ -1028,7 +1054,6 @@ omap_i2c_probe(struct platform_device *pdev)
 	struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data;
 	struct device_node	*node = pdev->dev.of_node;
 	const struct of_device_id *match;
-	irq_handler_t isr;
 	int irq;
 	int r;
 

@@ -1078,6 +1103,8 @@ omap_i2c_probe(struct platform_device *pdev)
 	dev->dev = &pdev->dev;
 	dev->irq = irq;
 
+	spin_lock_init(&dev->lock);
+
 	platform_set_drvdata(pdev, dev);
 	init_completion(&dev->cmd_complete);
 

@@ -1130,10 +1157,14 @@ omap_i2c_probe(struct platform_device *pdev)
 	/* reset ASAP, clearing any IRQs */
 	omap_i2c_init(dev);
 
-	isr = (dev->rev < OMAP_I2C_OMAP1_REV_2) ? omap_i2c_omap1_isr :
-								   omap_i2c_isr;
-	r = devm_request_irq(&pdev->dev, dev->irq, isr, IRQF_NO_SUSPEND,
-			     pdev->name, dev);
+	if (dev->rev < OMAP_I2C_OMAP1_REV_2)
+		r = devm_request_irq(&pdev->dev, dev->irq, omap_i2c_omap1_isr,
+				IRQF_NO_SUSPEND, pdev->name, dev);
+	else
+		r = devm_request_threaded_irq(&pdev->dev, dev->irq,
+				omap_i2c_isr, omap_i2c_isr_thread,
+				IRQF_NO_SUSPEND | IRQF_ONESHOT,
+				pdev->name, dev);
 
 	if (r) {
 		dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);

index e391370..6d38a57 100644
@@ -883,9 +883,6 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
 	u16 stat;
 	int err = 0, count = 0;
 
-	if (pm_runtime_suspended(dev->dev))
-		return IRQ_HANDLED;
-
 	spin_lock_irqsave(&dev->lock, flags);
 	do {
 		bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);

index 6d38a57..122f517 100644
@@ -55,6 +55,9 @@
 /* timeout waiting for the controller to respond */
 #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
 
+/* timeout for pm runtime autosuspend */
+#define OMAP_I2C_PM_TIMEOUT		1000	/* ms */
+
 /* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */
 enum {
 	OMAP_I2C_REV_REG = 0,

@@ -645,7 +648,8 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 
 	omap_i2c_wait_for_bb(dev);
 out:
-	pm_runtime_put(dev->dev);
+	pm_runtime_mark_last_busy(dev->dev);
+	pm_runtime_put_autosuspend(dev->dev);
 	return r;
 }
 

@@ -1113,6 +1117,9 @@ omap_i2c_probe(struct platform_device *pdev)
 		dev->regs = (u8 *)reg_map_ip_v1;
 
 	pm_runtime_enable(dev->dev);
+	pm_runtime_set_autosuspend_delay(dev->dev, OMAP_I2C_PM_TIMEOUT);
+	pm_runtime_use_autosuspend(dev->dev);
+
 	r = pm_runtime_get_sync(dev->dev);
 	if (IS_ERR_VALUE(r))
 		goto err_free_mem;

@@ -1190,7 +1197,8 @@ omap_i2c_probe(struct platform_device *pdev)
 
 	of_i2c_register_devices(adap);
 
-	pm_runtime_put(dev->dev);
+	pm_runtime_mark_last_busy(dev->dev);
+	pm_runtime_put_autosuspend(dev->dev);
 
 	return 0;
 

index 122f517..b149e32 100644
@@ -901,27 +901,26 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
 
 		if (!stat) {
 			/* my work here is done */
-			spin_unlock_irqrestore(&dev->lock, flags);
-			return IRQ_HANDLED;
+			goto out;
 		}
 
 		dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
 		if (count++ == 100) {
 			dev_warn(dev->dev, "Too much work in one IRQ\n");
-			goto out;
+			break;
 		}
 
 		if (stat & OMAP_I2C_STAT_NACK) {
 			err |= OMAP_I2C_STAT_NACK;
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
-			goto out;
+			break;
 		}
 
 		if (stat & OMAP_I2C_STAT_AL) {
 			dev_err(dev->dev, "Arbitration lost\n");
 			err |= OMAP_I2C_STAT_AL;
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_AL);
-			goto out;
+			break;
 		}
 
 		/*

@@ -934,7 +933,7 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
 						OMAP_I2C_STAT_XRDY |
 						OMAP_I2C_STAT_XDR |
 						OMAP_I2C_STAT_ARDY));
-			goto out;
+			break;
 		}
 
 		if (stat & OMAP_I2C_STAT_RDR) {

@@ -949,7 +948,7 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
 				i2c_omap_errata_i207(dev, stat);
 
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
-			continue;
+			break;
 		}
 
 		if (stat & OMAP_I2C_STAT_RRDY) {

@@ -972,10 +971,10 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
 
 			ret = omap_i2c_transmit_data(dev, num_bytes, true);
 			if (ret < 0)
-				goto out;
+				break;
 
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
-			continue;
+			break;
 		}
 
 		if (stat & OMAP_I2C_STAT_XRDY) {

@@ -987,7 +986,7 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
 
 			ret = omap_i2c_transmit_data(dev, num_bytes, false);
 			if (ret < 0)
-				goto out;
+				break;
 
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
 			continue;

@@ -997,19 +996,20 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
 			dev_err(dev->dev, "Receive overrun\n");
 			err |= OMAP_I2C_STAT_ROVR;
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ROVR);
-			goto out;
+			break;
 		}
 
 		if (stat & OMAP_I2C_STAT_XUDF) {
 			dev_err(dev->dev, "Transmit underflow\n");
 			err |= OMAP_I2C_STAT_XUDF;
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XUDF);
-			goto out;
+			break;
 		}
 	} while (stat);
 
-out:
 	omap_i2c_complete_cmd(dev, err);
+
+out:
 	spin_unlock_irqrestore(&dev->lock, flags);
 
 	return IRQ_HANDLED;