If period_cycles is 0, prescale becomes silly.
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This just leaves include/asm-arm/plat-* to deal with.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Make the return of pwm_request() be more informative than just
being NULL on error by using PTR_ERR() to respond with an
approriate error.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Allow pwm_enable()/pwm_disable() to be called as many times
as the driver wants (and not even count them).
The PWM model is different from things like the clock API
where we need enable counting, because PWMs have one
exclusive user per PWM whereas the clock API can have
multiple users of the same clock.
Acked-by: Neric miao <eric.miao@marvell.com>
Signed-off-by: NRobert Jarzmik <rjarzmik@free.fr>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

 as a module

Without a GPL-compatible license this driver cannot be built as a module,
because the platform_driver_* API is only exported to GPL modules.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@pengutronix.de>
Acked-by: NEric Miao <eric.miao@marvell.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Currently PWM0/2 (pxa27x_device_pwm0 at 0x40b00000 and 0x40b00010
are registered as as pwm_id 0 and 1, PWM1/3 (pxa27x_device_pwm1 at
0x40c00000 and 0x40c00010) are registered as pwm_id 2 and 3.
This patch corrects the pwm_ids to match the documented register names.
Signed-off-by: NPhilipp Zabel <philipp.zabel@gmail.com>
Acked-by: NEric Miao <eric.miao@marvell.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch mainly from Eric Miao, with minor edits by rmk.

Note: PWM0 and PWM2 share the same register I/O space and clock gating
on pxa{27x, 3xx}, thus PWM2 is treated in the driver as a child PWM of
PWM0. And this is also true for PWM1/3.
Signed-off-by: Neric miao <eric.miao@marvell.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>