On Wed, 1 Mar 2017 18:16:02 +0800 David Wu <[email protected]> wrote:
> From: "david.wu" <[email protected]> > > If the pwm was not enabled at uboot loader, pwm could not work for clock > always disabled at pwm driver. The pwm clock is enabled at beginning of > pwm_apply(), but disabled at end of pwm_apply(). > > If the pwm was enabled at uboot loader, pwm clock is always enabled unless > closed by ATF. The pwm-backlight might turn off the power at early suspend, > should disable pwm clock for saving power consume. > > It is important to provide opportunity to enable/disable clock at pwm driver, > the pwm consumer should ensure correct order to call pwm enable/disable, and > pwm driver ensure state of pwm clock synchronized with pwm enabled state. > > Fixes: 2bf1c98aa5a4 ("pwm: rockchip: Add support for atomic update") > Cc: [email protected] > Signed-off-by: David Wu <[email protected]> > Reviewed-by: Boris Brezillon <[email protected]> > --- > drivers/pwm/pwm-rockchip.c | 40 +++++++++++++++++++++++++++++++++------- > 1 file changed, 33 insertions(+), 7 deletions(-) > > diff --git a/drivers/pwm/pwm-rockchip.c b/drivers/pwm/pwm-rockchip.c > index ef89df1..dbee3c3 100644 > --- a/drivers/pwm/pwm-rockchip.c > +++ b/drivers/pwm/pwm-rockchip.c > @@ -191,6 +191,28 @@ static int rockchip_pwm_config(struct pwm_chip *chip, > struct pwm_device *pwm, > return 0; > } > > +static int rk_pwm_enable(struct pwm_chip *chip, > + struct pwm_device *pwm, > + bool enable, > + enum pwm_polarity polarity) You didn't change the function name: s/rk_pwm_enable/rockchip_pwm_enable/ > +{ > + struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip); > + int ret; > + > + if (enable) { > + ret = clk_enable(pc->clk); > + if (ret) > + return ret; > + } > + > + pc->data->set_enable(chip, pwm, enable, polarity); > + > + if (!enable) > + clk_disable(pc->clk); > + > + return 0; > +} > + > static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, > struct pwm_state *state) > { > @@ -207,22 +229,26 @@ static int rockchip_pwm_apply(struct pwm_chip *chip, > struct pwm_device *pwm, > return ret; > > if (state->polarity != curstate.polarity && enabled) { > - pc->data->set_enable(chip, pwm, false, state->polarity); > + ret = rk_pwm_enable(chip, pwm, false, state->polarity); > + if (ret) > + goto out; > enabled = false; > } > > ret = rockchip_pwm_config(chip, pwm, state->duty_cycle, state->period); > if (ret) { > if (enabled != curstate.enabled) > - pc->data->set_enable(chip, pwm, !enabled, > - state->polarity); > - > + rk_pwm_enable(chip, pwm, !enabled, > + state->polarity); > goto out; > } > > - if (state->enabled != enabled) > - pc->data->set_enable(chip, pwm, state->enabled, > - state->polarity); > + if (state->enabled != enabled) { > + ret = rk_pwm_enable(chip, pwm, state->enabled, > + state->polarity); > + if (ret) > + goto out; > + } > > /* > * Update the state with the real hardware, which can differ a bit
