1 files changed, 9 insertions, 0 deletions

diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index e7a709710592..64eee9551b22 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -283,6 +283,7 @@ static int i2cdev_ioctl(struct inode *inode, struct file *file,
                     (data_arg.size != I2C_SMBUS_WORD_DATA) &&
                     (data_arg.size != I2C_SMBUS_PROC_CALL) &&
                     (data_arg.size != I2C_SMBUS_BLOCK_DATA) &&
+                    (data_arg.size != I2C_SMBUS_I2C_BLOCK_BROKEN) &&
                     (data_arg.size != I2C_SMBUS_I2C_BLOCK_DATA) &&
                     (data_arg.size != I2C_SMBUS_BLOCK_PROC_CALL)) {
                         dev_dbg(&client->adapter->dev,
@@ -329,10 +330,18 @@ static int i2cdev_ioctl(struct inode *inode, struct file *file,
 
                 if ((data_arg.size == I2C_SMBUS_PROC_CALL) ||
                     (data_arg.size == I2C_SMBUS_BLOCK_PROC_CALL) ||
+                    (data_arg.size == I2C_SMBUS_I2C_BLOCK_DATA) ||
                     (data_arg.read_write == I2C_SMBUS_WRITE)) {
                         if (copy_from_user(&temp, data_arg.data, datasize))
                                 return -EFAULT;
                 }
+                if (data_arg.size == I2C_SMBUS_I2C_BLOCK_BROKEN) {
+                        /* Convert old I2C block commands to the new
+                           convention. This preserves binary compatibility. */
+                        data_arg.size = I2C_SMBUS_I2C_BLOCK_DATA;
+                        if (data_arg.read_write == I2C_SMBUS_READ)
+                                temp.block[0] = I2C_SMBUS_BLOCK_MAX;
+                }
                 res = i2c_smbus_xfer(client->adapter,client->addr,client->flags,
                       data_arg.read_write,
                       data_arg.command,data_arg.size,&temp);