[RFC PATCH 12/15] pwm: rockchip: add initial state retrieval
Boris Brezillon
boris.brezillon at free-electrons.com
Thu Jul 2 00:46:50 PDT 2015
On Wed, 01 Jul 2015 23:44:46 +0200
Heiko Stübner <heiko at sntech.de> wrote:
> Hi Boris,
>
> Am Mittwoch, 1. Juli 2015, 10:21:58 schrieb Boris Brezillon:
> > Implement the ->init_state() function to expose initial state.
> >
> > Signed-off-by: Boris Brezillon <boris.brezillon at free-electrons.com>
> > ---
>
> [...]
>
> > @@ -98,6 +110,36 @@ static void rockchip_pwm_set_enable_v2(struct pwm_chip
> > *chip, writel_relaxed(val, pc->base + pc->data->regs.ctrl);
> > }
> >
> > +static void rockchip_pwm_init_state(struct pwm_chip *chip,
> > + struct pwm_device *pwm)
> > +{
> > + struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
> > + unsigned long clk_rate;
> > + u64 tmp;
> > + int ret;
> > +
> > + ret = clk_enable(pc->clk);
> > + if (ret)
> > + return;
> > +
> > + clk_rate = clk_get_rate(pc->clk);
> > +
> > + tmp = readl(pc->base + pc->data->regs.period);
> > + tmp *= pc->data->prescaler * NSEC_PER_SEC;
> > + tmp = do_div(tmp, clk_rate);
>
> I guess you want to have the division result here and not the remainder, so
> - tmp = do_div(tmp, clk_rate);
> + do_div(tmp, clk_rate);
>
Oh crap. I make the same mistake over and over again.
[...]
> > static const struct rockchip_pwm_data pwm_data_v2 = {
> > @@ -207,6 +252,7 @@ static const struct rockchip_pwm_data pwm_data_v2 = {
> > .prescaler = 1,
> > .ops = &rockchip_pwm_ops_v2,
> > .set_enable = rockchip_pwm_set_enable_v2,
> > + .init = rockchip_pwm_init_v2,
>
> you're referencing the v2 init here, but only add it in the next patch?
> [pwm: rockchip: add support for atomic update]
Yep, this function should be added in this patch.
Thanks,
Boris
--
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
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