i2c: rcar: disable runtime PM correctly in slave mode

When we also are I2C slave, we need to disable runtime PM because the
address detection mechanism needs to be active all the time. However, we
can reenable runtime PM once the slave instance was unregistered. So,
use pm_runtime_get_sync/put to achieve this, since it has proper
refcounting. pm_runtime_allow/forbid is like a global knob controllable
from userspace which is unsuitable here.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
This commit is contained in:
Wolfram Sang 2015-12-16 20:05:18 +01:00 committed by Wolfram Sang
parent e79e72c5a2
commit b4cd08aa1f

View File

@ -576,7 +576,7 @@ static int rcar_reg_slave(struct i2c_client *slave)
if (slave->flags & I2C_CLIENT_TEN)
return -EAFNOSUPPORT;
pm_runtime_forbid(rcar_i2c_priv_to_dev(priv));
pm_runtime_get_sync(rcar_i2c_priv_to_dev(priv));
priv->slave = slave;
rcar_i2c_write(priv, ICSAR, slave->addr);
@ -598,7 +598,7 @@ static int rcar_unreg_slave(struct i2c_client *slave)
priv->slave = NULL;
pm_runtime_allow(rcar_i2c_priv_to_dev(priv));
pm_runtime_put(rcar_i2c_priv_to_dev(priv));
return 0;
}