On Fri, Jan 11, 2019 at 10:51:15AM +0530, Sheetal Tigadoli wrote: > From: Praveen Kumar B <praveen.b@xxxxxxxxxxxx> > > Add support for new version of pwm-kona. > Add support to make PWM changes configured and stable. > > Signed-off-by: Praveen Kumar B <praveen.b@xxxxxxxxxxxx> > Reviewed-by: Ray Jui <ray.jui@xxxxxxxxxxxx> > Reviewed-by: Scott Branden <scott.branden@xxxxxxxxxxxx> > Signed-off-by: Sheetal Tigadoli <sheetal.tigadoli@xxxxxxxxxxxx> > --- > drivers/pwm/pwm-bcm-kona.c | 128 ++++++++++++++++++++++++++++++++++----------- > 1 file changed, 98 insertions(+), 30 deletions(-) > > diff --git a/drivers/pwm/pwm-bcm-kona.c b/drivers/pwm/pwm-bcm-kona.c > index 09a95ae..2b44ad8 100644 > --- a/drivers/pwm/pwm-bcm-kona.c > +++ b/drivers/pwm/pwm-bcm-kona.c > @@ -45,30 +45,39 @@ > * high or low depending on its state at that exact instant. > */ > > -#define PWM_CONTROL_OFFSET (0x00000000) > +#define PWM_CONTROL_OFFSET 0x00000000 > #define PWM_CONTROL_SMOOTH_SHIFT(chan) (24 + (chan)) > #define PWM_CONTROL_TYPE_SHIFT(chan) (16 + (chan)) > #define PWM_CONTROL_POLARITY_SHIFT(chan) (8 + (chan)) > #define PWM_CONTROL_TRIGGER_SHIFT(chan) (chan) > > -#define PRESCALE_OFFSET (0x00000004) > +#define PRESCALE_OFFSET 0x00000004 > #define PRESCALE_SHIFT(chan) ((chan) << 2) > #define PRESCALE_MASK(chan) (0x7 << PRESCALE_SHIFT(chan)) > -#define PRESCALE_MIN (0x00000000) > -#define PRESCALE_MAX (0x00000007) > +#define PRESCALE_MIN 0x00000000 > +#define PRESCALE_MAX 0x00000007 Hi Praveen These changes are unrelated to adding support for a new PWM. So ideally they should be in a separate patch. > +static int kona_pwmc_wait_stable(struct pwm_chip *chip, unsigned int chan, > + unsigned int kona_ver) > +{ > + struct kona_pwmc *kp = to_kona_pwmc(chip); > + unsigned int value; > + unsigned int count = PWM_MONITOR_TIMEOUT_US * 1000; > + > + switch (kona_ver) { > + case KONA_PWM_V1: > + /* > + * There must be a min 400ns delay between clearing trigger and > + * settingit. Failing to do this may result in no PWM signal. > + */ > + ndelay(400); > + return 0; > + case KONA_PWM_V2: > + do { > + value = readl(kp->base + PWM_MONITOR_OFFSET); > + if (!(value & (BIT(chan)))) > + return 0; > + ndelay(1); > + } while (count--); You can probably use readl_poll_timeout() here. Andrew