bq27x00: Use single i2c_transfer call for property read
authorGrazvydas Ignotas <notasas@gmail.com>
Tue, 15 Feb 2011 21:27:35 +0000 (23:27 +0200)
committerLars-Peter Clausen <lars@metafoo.de>
Tue, 22 Feb 2011 10:02:48 +0000 (11:02 +0100)
Doing this by using 2 calls sometimes results in unexpected
values being returned on OMAP3 i2c controller.

Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
drivers/power/bq27x00_battery.c

index 740a0ac..59e68db 100644 (file)
@@ -565,31 +565,26 @@ static DEFINE_MUTEX(battery_mutex);
 static int bq27x00_read_i2c(struct bq27x00_device_info *di, u8 reg, bool single)
 {
        struct i2c_client *client = to_i2c_client(di->dev);
-       struct i2c_msg msg;
+       struct i2c_msg msg[2];
        unsigned char data[2];
        int ret;
 
        if (!client->adapter)
                return -ENODEV;
 
-       msg.addr = client->addr;
-       msg.flags = 0;
-       msg.len = 1;
-       msg.buf = data;
-
-       data[0] = reg;
-       ret = i2c_transfer(client->adapter, &msg, 1);
-
-       if (ret < 0)
-               return ret;
-
+       msg[0].addr = client->addr;
+       msg[0].flags = 0;
+       msg[0].buf = &reg;
+       msg[0].len = sizeof(reg);
+       msg[1].addr = client->addr;
+       msg[1].flags = I2C_M_RD;
+       msg[1].buf = data;
        if (single)
-               msg.len = 1;
+               msg[1].len = 1;
        else
-               msg.len = 2;
+               msg[1].len = 2;
 
-       msg.flags = I2C_M_RD;
-       ret = i2c_transfer(client->adapter, &msg, 1);
+       ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
        if (ret < 0)
                return ret;