Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/…

…kernel/git/wsa/linux

Pull i2c fixes from Wolfram Sang:
 "The ismt driver had a problem with a rarely used transaction type and
  the designware driver was made even more robust against non standard
  ACPI tables"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: designware: Round down ACPI provided clk to nearest supported clk
  i2c: ismt: Return EMSGSIZE for block reads with bogus length
  i2c: ismt: Don't duplicate the receive length for block reads

drivers/i2c/busses/i2c-designware-platdrv.c

@@ -256,7 +256,8 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 	struct dw_i2c_dev *dev;
 	u32 acpi_speed, ht = 0;
 	struct resource *mem;
-	int irq, ret;
+	int i, irq, ret;
+	const int supported_speeds[] = { 0, 100000, 400000, 1000000, 3400000 };
 
 	irq = platform_get_irq(pdev, 0);
 	if (irq < 0)
@@ -297,9 +298,16 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 	}
 
 	acpi_speed = i2c_acpi_find_bus_speed(&pdev->dev);
-	/* Some broken DSTDs use 1MiHz instead of 1MHz */
-	if (acpi_speed == 1048576)
-		acpi_speed = 1000000;
+	/*
+	 * Some DSTDs use a non standard speed, round down to the lowest
+	 * standard speed.
+	 */
+	for (i = 1; i < ARRAY_SIZE(supported_speeds); i++) {
+		if (acpi_speed < supported_speeds[i])
+			break;
+	}
+	acpi_speed = supported_speeds[i - 1];
+
 	/*
 	 * Find bus speed from the "clock-frequency" device property, ACPI
 	 * or by using fast mode if neither is set.

drivers/i2c/busses/i2c-ismt.c

@@ -341,8 +341,10 @@ static int ismt_process_desc(const struct ismt_desc *desc,
 			break;
 		case I2C_SMBUS_BLOCK_DATA:
 		case I2C_SMBUS_I2C_BLOCK_DATA:
-			memcpy(&data->block[1], dma_buffer, desc->rxbytes);
-			data->block[0] = desc->rxbytes;
+			if (desc->rxbytes != dma_buffer[0] + 1)
+				return -EMSGSIZE;
+
+			memcpy(data->block, dma_buffer, desc->rxbytes);
 			break;
 		}
 		return 0;