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author | Johannes Berg | 2015-06-10 12:44:58 +0200 |
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committer | Johannes Berg | 2015-06-10 12:45:09 +0200 |
commit | 206c59d1d7d42bcafc1d7f1e476e87e4427e2345 (patch) | |
tree | a2f99470bd0fe43f5cf57812fca969bb3ca3c451 /drivers/pwm/pwm-samsung.c | |
parent | mac80211: Fix a case of incorrect metric used when forwarding a PREQ (diff) | |
parent | Merge tag 'batman-adv-for-davem' of git://git.open-mesh.org/linux-merge (diff) | |
download | kernel-qcow2-linux-206c59d1d7d42bcafc1d7f1e476e87e4427e2345.tar.gz kernel-qcow2-linux-206c59d1d7d42bcafc1d7f1e476e87e4427e2345.tar.xz kernel-qcow2-linux-206c59d1d7d42bcafc1d7f1e476e87e4427e2345.zip |
Merge remote-tracking branch 'net-next/master' into mac80211-next
Merge back net-next to get wireless driver changes (from Kalle)
to be able to create the API change across all trees properly.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'drivers/pwm/pwm-samsung.c')
-rw-r--r-- | drivers/pwm/pwm-samsung.c | 32 |
1 files changed, 31 insertions, 1 deletions
diff --git a/drivers/pwm/pwm-samsung.c b/drivers/pwm/pwm-samsung.c index 3e9b5835a4af..ff201e1b9219 100644 --- a/drivers/pwm/pwm-samsung.c +++ b/drivers/pwm/pwm-samsung.c @@ -269,12 +269,31 @@ static void pwm_samsung_disable(struct pwm_chip *chip, struct pwm_device *pwm) spin_unlock_irqrestore(&samsung_pwm_lock, flags); } +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); + + spin_unlock_irqrestore(&samsung_pwm_lock, flags); +} + static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns) { struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip); struct samsung_pwm_channel *chan = pwm_get_chip_data(pwm); - u32 tin_ns = chan->tin_ns, tcnt, tcmp; + u32 tin_ns = chan->tin_ns, tcnt, tcmp, oldtcmp; /* * We currently avoid using 64bit arithmetic by using the @@ -288,6 +307,7 @@ static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm, return 0; tcnt = readl(our_chip->base + REG_TCNTB(pwm->hwpwm)); + oldtcmp = readl(our_chip->base + REG_TCMPB(pwm->hwpwm)); /* We need tick count for calculation, not last tick. */ ++tcnt; @@ -335,6 +355,16 @@ static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm, writel(tcnt, our_chip->base + REG_TCNTB(pwm->hwpwm)); writel(tcmp, our_chip->base + REG_TCMPB(pwm->hwpwm)); + /* + * In case the PWM is currently at 100% duty cycle, force a manual + * update to prevent the signal staying high if the PWM is disabled + * shortly afer this update (before it autoreloaded the new values). + */ + if (oldtcmp == (u32) -1) { + dev_dbg(our_chip->chip.dev, "Forcing manual update"); + pwm_samsung_manual_update(our_chip, pwm); + } + chan->period_ns = period_ns; chan->tin_ns = tin_ns; chan->duty_ns = duty_ns; |