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

2 files changed, 16 insertions, 6 deletions

diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 57248bccadbc..2b98a173136f 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/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.
diff --git a/drivers/i2c/busses/i2c-ismt.c b/drivers/i2c/busses/i2c-ismt.c
index e98e44e584a4..22ffcb73c185 100644
--- a/drivers/i2c/busses/i2c-ismt.c
+++ b/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;