[media] em28xx: Only change I2C bus inside em28xx-i2c

There's currently a bug on em28xx-i2c that makes it write the
wrong values to register 06, that controlls the I2C bus speed
and bus.

Fix it to change only the I2C bus flag.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/usb/em28xx/em28xx-i2c.c b/drivers/media/usb/em28xx/em28xx-i2c.c
index de9b2086ab2df919ff8ed9124d889d4a7728bc68..9e2fa41044b35fe9db4957df25a258123fb0b2d1 100644 (file)
--- a/drivers/media/usb/em28xx/em28xx-i2c.c
+++ b/drivers/media/usb/em28xx/em28xx-i2c.c
@@ -284,6 +284,7 @@ static int em28xx_i2c_xfer(struct i2c_adapter *i2c_adap,
        struct em28xx *dev = i2c_bus->dev;
        unsigned bus = i2c_bus->bus;
        int addr, rc, i, byte;
+       u8 reg;
 
        rc = rt_mutex_trylock(&dev->i2c_bus_lock);
        if (rc < 0)
@@ -292,10 +293,11 @@ static int em28xx_i2c_xfer(struct i2c_adapter *i2c_adap,
        /* Switch I2C bus if needed */
        if (bus != dev->cur_i2c_bus) {
                if (bus == 1)
-                       dev->cur_i2c_bus |= EM2874_I2C_SECONDARY_BUS_SELECT;
+                       reg = EM2874_I2C_SECONDARY_BUS_SELECT;
                else
-                       dev->cur_i2c_bus &= ~EM2874_I2C_SECONDARY_BUS_SELECT;
-               em28xx_write_reg(dev, EM28XX_R06_I2C_CLK, dev->cur_i2c_bus);
+                       reg = 0;
+               em28xx_write_reg_bits(dev, EM28XX_R06_I2C_CLK, reg,
+                                     EM2874_I2C_SECONDARY_BUS_SELECT);
                dev->cur_i2c_bus = bus;
        }