tree 8a68b6cc78511ef077c56fecbc854dc991050dd2
parent e2afca6988c335d2ec7b66f2fadcd63286570bf8
author Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> 1385658705 +0100
committer Simon Horman <horms+renesas@verge.net.au> 1386982692 +0900

serial: sh-sci: Don't enable/disable port from within break timer

The break timer accesses hardware registers and thus requires the port
to be enabled. It currently ensures this by enabling the port at the
beginning of the timer handler, and disabling it at the end. However,
the enable/disable operations call the runtime PM sync functions, which
are not allowed in atomic context. The current situation is thus broken.

This change relies on non-atomic code to enable/disable the port. The
break timer will only be started from the IRQ handler, which already
runs with the port enabled. We just need to ensure that the port won't
be disabled with the timer running, and that's easily done by just
cancelling the timer in the port disable function.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Magnus Damm <damm@opensource.se>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>