[media] i2c: Export an unlocked flavor of i2c_transfer
authorJean Delvare <khali@linux-fr.org>
Fri, 29 Jun 2012 10:47:19 +0000 (07:47 -0300)
committerMauro Carvalho Chehab <mchehab@redhat.com>
Fri, 29 Jun 2012 22:03:25 +0000 (19:03 -0300)
commitb37d2a3a75cb0e72e18c29336cb2095b63dabfc8
tree212e01d73f40881626b54ef4811de3a061788989
parenta99817ca60d206be3645d156f755cf065e949c58
[media] i2c: Export an unlocked flavor of i2c_transfer

Some drivers (in particular for TV cards) need exclusive access to
their I2C buses for specific operations. Export an unlocked flavor
of i2c_transfer to give them full control.

The unlocked flavor has the following limitations:
* Obviously, caller must hold the i2c adapter lock.
* No debug messages are logged. We don't want to log messages while
  holding a rt_mutex.
* No check is done on the existence of adap->algo->master_xfer. It
  is thus the caller's responsibility to ensure that the function is
  OK to call.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
drivers/i2c/i2c-core.c
include/linux/i2c.h