tree aba6582cd3bf0a8f2fd58b5f47ffd3c60486a527
parent 6cfda7fbebe8a4fd33ea5722fa0212f98f643c35
author Roger Quadros <rogerq@ti.com> 1421158991 +0200
committer Marc Kleine-Budde <mkl@pengutronix.de> 1421337480 +0100

can: c_can: use regmap_update_bits() to modify RAMINIT register

use of regmap_read() and regmap_write() in c_can_hw_raminit_syscon()
is not safe as the RAMINIT register can be shared between different drivers
at least for TI SoCs.

To make the modification atomic we switch to using regmap_update_bits().

regmap_update_bits() skips writing to the register if it's read content is the
same as what is going to be written. This causes an issue for us when we
need to clear the DONE bit with the initial condition START:0, DONE:1 as
DONE bit must be written with 1 to clear it.

So we defer the clearing of DONE bit to later when we set the START bit.
There we are sure that START bit is changed from 0 to 1 so the write of
1 to already set DONE bit will happen.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>