V4L/DVB: ov7670: Don't use SMBUS I/O

Contrary to my earlier belief, the ov7670 is not actually an SMBUS device,
though it will pretend to be one if it's in a good mood.  Unfortunately,
it's rarely in a good mood, especially on the XO 1.5.  So use low-level i2c
I/O instead.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/video/ov7670.c b/drivers/media/video/ov7670.c
index b2e6f8e730a32cb664fbca7c6adec51459eb8926..95507770f120703fc75dcdf65fca450e0e8fd70b 100644 (file)
--- a/drivers/media/video/ov7670.c
+++ b/drivers/media/video/ov7670.c
@@ -410,16 +410,33 @@ static struct regval_list ov7670_fmt_raw[] = {
 /*
  * Low-level register I/O.
  */
-
 static int ov7670_read(struct v4l2_subdev *sd, unsigned char reg,
                unsigned char *value)
 {
        struct i2c_client *client = v4l2_get_subdevdata(sd);
+       u8 data = reg;
+       struct i2c_msg msg;
        int ret;
 
-       ret = i2c_smbus_read_byte_data(client, reg);
+       /*
+        * Send out the register address...
+        */
+       msg.addr = client->addr;
+       msg.flags = 0;
+       msg.len = 1;
+       msg.buf = &data;
+       ret = i2c_transfer(client->adapter, &msg, 1);
+       if (ret < 0) {
+               printk(KERN_ERR "Error %d on register write\n", ret);
+               return ret;
+       }
+       /*
+        * ...then read back the result.
+        */
+       msg.flags = I2C_M_RD;
+       ret = i2c_transfer(client->adapter, &msg, 1);
        if (ret >= 0) {
-               *value = (unsigned char)ret;
+               *value = data;
                ret = 0;
        }
        return ret;
@@ -430,8 +447,17 @@ static int ov7670_write(struct v4l2_subdev *sd, unsigned char reg,
                unsigned char value)
 {
        struct i2c_client *client = v4l2_get_subdevdata(sd);
-       int ret = i2c_smbus_write_byte_data(client, reg, value);
+       struct i2c_msg msg;
+       unsigned char data[2] = { reg, value };
+       int ret;
 
+       msg.addr = client->addr;
+       msg.flags = 0;
+       msg.len = 2;
+       msg.buf = data;
+       ret = i2c_transfer(client->adapter, &msg, 1);
+       if (ret > 0)
+               ret = 0;
        if (reg == REG_COM7 && (value & COM7_RESET))
                msleep(5);  /* Wait for reset to run */
        return ret;