diff options
Diffstat (limited to 'drivers/pwm/pwm-bcm-kona.c')
-rw-r--r-- | drivers/pwm/pwm-bcm-kona.c | 90 |
1 files changed, 58 insertions, 32 deletions
diff --git a/drivers/pwm/pwm-bcm-kona.c b/drivers/pwm/pwm-bcm-kona.c index 64148f5f81d0..f171169c1c1f 100644 --- a/drivers/pwm/pwm-bcm-kona.c +++ b/drivers/pwm/pwm-bcm-kona.c @@ -109,10 +109,10 @@ static void kona_pwmc_apply_settings(struct kona_pwmc *kp, unsigned int chan) } static int kona_pwmc_config(struct pwm_chip *chip, struct pwm_device *pwm, - int duty_ns, int period_ns) + u64 duty_ns, u64 period_ns) { struct kona_pwmc *kp = to_kona_pwmc(chip); - u64 val, div, rate; + u64 div, rate; unsigned long prescale = PRESCALE_MIN, pc, dc; unsigned int value, chan = pwm->hwpwm; @@ -132,10 +132,8 @@ static int kona_pwmc_config(struct pwm_chip *chip, struct pwm_device *pwm, while (1) { div = 1000000000; div *= 1 + prescale; - val = rate * period_ns; - pc = div64_u64(val, div); - val = rate * duty_ns; - dc = div64_u64(val, div); + pc = mul_u64_u64_div_u64(rate, period_ns, div); + dc = mul_u64_u64_div_u64(rate, duty_ns, div); /* If duty_ns or period_ns are not achievable then return */ if (pc < PERIOD_COUNT_MIN) @@ -150,25 +148,18 @@ static int kona_pwmc_config(struct pwm_chip *chip, struct pwm_device *pwm, return -EINVAL; } - /* - * Don't apply settings if disabled. The period and duty cycle are - * always calculated above to ensure the new values are - * validated immediately instead of on enable. - */ - if (pwm_is_enabled(pwm)) { - kona_pwmc_prepare_for_settings(kp, chan); + kona_pwmc_prepare_for_settings(kp, chan); - value = readl(kp->base + PRESCALE_OFFSET); - value &= ~PRESCALE_MASK(chan); - value |= prescale << PRESCALE_SHIFT(chan); - writel(value, kp->base + PRESCALE_OFFSET); + value = readl(kp->base + PRESCALE_OFFSET); + value &= ~PRESCALE_MASK(chan); + value |= prescale << PRESCALE_SHIFT(chan); + writel(value, kp->base + PRESCALE_OFFSET); - writel(pc, kp->base + PERIOD_COUNT_OFFSET(chan)); + writel(pc, kp->base + PERIOD_COUNT_OFFSET(chan)); - writel(dc, kp->base + DUTY_CYCLE_HIGH_OFFSET(chan)); + writel(dc, kp->base + DUTY_CYCLE_HIGH_OFFSET(chan)); - kona_pwmc_apply_settings(kp, chan); - } + kona_pwmc_apply_settings(kp, chan); return 0; } @@ -216,13 +207,6 @@ static int kona_pwmc_enable(struct pwm_chip *chip, struct pwm_device *pwm) return ret; } - ret = kona_pwmc_config(chip, pwm, pwm_get_duty_cycle(pwm), - pwm_get_period(pwm)); - if (ret < 0) { - clk_disable_unprepare(kp->clk); - return ret; - } - return 0; } @@ -248,11 +232,53 @@ static void kona_pwmc_disable(struct pwm_chip *chip, struct pwm_device *pwm) clk_disable_unprepare(kp->clk); } +static int kona_pwmc_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + int err; + struct kona_pwmc *kp = to_kona_pwmc(chip); + bool enabled = pwm->state.enabled; + + if (state->polarity != pwm->state.polarity) { + if (enabled) { + kona_pwmc_disable(chip, pwm); + enabled = false; + } + + err = kona_pwmc_set_polarity(chip, pwm, state->polarity); + if (err) + return err; + + pwm->state.polarity = state->polarity; + } + + if (!state->enabled) { + if (enabled) + kona_pwmc_disable(chip, pwm); + return 0; + } else if (!enabled) { + /* + * This is a bit special here, usually the PWM should only be + * enabled when duty and period are setup. But before this + * driver was converted to .apply it was done the other way + * around and so this behaviour was kept even though this might + * result in a glitch. This might be improvable by someone with + * hardware and/or documentation. + */ + err = kona_pwmc_enable(chip, pwm); + if (err) + return err; + } + + err = kona_pwmc_config(pwm->chip, pwm, state->duty_cycle, state->period); + if (err && !pwm->state.enabled) + clk_disable_unprepare(kp->clk); + + return err; +} + static const struct pwm_ops kona_pwm_ops = { - .config = kona_pwmc_config, - .set_polarity = kona_pwmc_set_polarity, - .enable = kona_pwmc_enable, - .disable = kona_pwmc_disable, + .apply = kona_pwmc_apply, .owner = THIS_MODULE, }; |