diff options
Diffstat (limited to 'drivers/pwm/pwm-samsung.c')
| -rw-r--r-- | drivers/pwm/pwm-samsung.c | 30 |
1 files changed, 22 insertions, 8 deletions
diff --git a/drivers/pwm/pwm-samsung.c b/drivers/pwm/pwm-samsung.c index dd94c4312a0c..0a4ff55fad04 100644 --- a/drivers/pwm/pwm-samsung.c +++ b/drivers/pwm/pwm-samsung.c @@ -117,6 +117,20 @@ static inline unsigned int to_tcon_channel(unsigned int channel) return (channel == 0) ? 0 : (channel + 1); } +static void __pwm_samsung_manual_update(struct samsung_pwm_chip *chip, + struct pwm_device *pwm) +{ + unsigned int tcon_chan = to_tcon_channel(pwm->hwpwm); + u32 tcon; + + tcon = readl(chip->base + REG_TCON); + tcon |= TCON_MANUALUPDATE(tcon_chan); + writel(tcon, chip->base + REG_TCON); + + tcon &= ~TCON_MANUALUPDATE(tcon_chan); + writel(tcon, chip->base + REG_TCON); +} + static void pwm_samsung_set_divisor(struct samsung_pwm_chip *pwm, unsigned int channel, u8 divisor) { @@ -276,6 +290,13 @@ static void pwm_samsung_disable(struct pwm_chip *chip, struct pwm_device *pwm) tcon &= ~TCON_AUTORELOAD(tcon_chan); writel(tcon, our_chip->base + REG_TCON); + /* + * In case the PWM is at 100% duty cycle, force a manual + * update to prevent the signal from staying high. + */ + if (readl(our_chip->base + REG_TCMPB(pwm->hwpwm)) == (u32)-1U) + __pwm_samsung_manual_update(our_chip, pwm); + our_chip->disabled_mask |= BIT(pwm->hwpwm); spin_unlock_irqrestore(&samsung_pwm_lock, flags); @@ -284,18 +305,11 @@ static void pwm_samsung_disable(struct pwm_chip *chip, struct pwm_device *pwm) static void pwm_samsung_manual_update(struct samsung_pwm_chip *chip, struct pwm_device *pwm) { - unsigned int tcon_chan = to_tcon_channel(pwm->hwpwm); - u32 tcon; unsigned long flags; spin_lock_irqsave(&samsung_pwm_lock, flags); - tcon = readl(chip->base + REG_TCON); - tcon |= TCON_MANUALUPDATE(tcon_chan); - writel(tcon, chip->base + REG_TCON); - - tcon &= ~TCON_MANUALUPDATE(tcon_chan); - writel(tcon, chip->base + REG_TCON); + __pwm_samsung_manual_update(chip, pwm); spin_unlock_irqrestore(&samsung_pwm_lock, flags); } |