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| author | Paul Cercueil <paul@crapouillou.net> | 2020-03-23 15:24:21 +0100 |
|---|---|---|
| committer | Thierry Reding <thierry.reding@gmail.com> | 2020-03-30 18:03:10 +0200 |
| commit | a2005fc791798f40cc9895b6abda8fbc7a168174 (patch) | |
| tree | 806a24d62ee0d13e18722fb14856f304f487b4ab /drivers/pwm | |
| parent | c2693514a0a1ec3abcb4673775af3edc797e8a07 (diff) | |
| download | linux-a2005fc791798f40cc9895b6abda8fbc7a168174.tar.gz linux-a2005fc791798f40cc9895b6abda8fbc7a168174.tar.bz2 linux-a2005fc791798f40cc9895b6abda8fbc7a168174.zip | |
pwm: jz4740: Allow selection of PWM channels 0 and 1
The TCU channels 0 and 1 were previously reserved for system tasks, and
thus unavailable for PWM.
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Tested-by: Mathieu Malaterre <malat@debian.org>
Tested-by: Artur Rojek <contact@artur-rojek.eu>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'drivers/pwm')
| -rw-r--r-- | drivers/pwm/pwm-jz4740.c | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/drivers/pwm/pwm-jz4740.c b/drivers/pwm/pwm-jz4740.c index 549e6c750bac..3cd5c054ad9a 100644 --- a/drivers/pwm/pwm-jz4740.c +++ b/drivers/pwm/pwm-jz4740.c @@ -33,6 +33,19 @@ static inline struct jz4740_pwm_chip *to_jz4740(struct pwm_chip *chip) return container_of(chip, struct jz4740_pwm_chip, chip); } +static bool jz4740_pwm_can_use_chn(struct jz4740_pwm_chip *jz, + unsigned int channel) +{ + /* Enable all TCU channels for PWM use by default except channels 0/1 */ + u32 pwm_channels_mask = GENMASK(NUM_PWM - 1, 2); + + device_property_read_u32(jz->chip.dev->parent, + "ingenic,pwm-channels-mask", + &pwm_channels_mask); + + return !!(pwm_channels_mask & BIT(channel)); +} + static int jz4740_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) { struct jz4740_pwm_chip *jz = to_jz4740(chip); @@ -40,11 +53,7 @@ static int jz4740_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) char name[16]; int err; - /* - * Timers 0 and 1 are used for system tasks, so they are unavailable - * for use as PWMs. - */ - if (pwm->hwpwm < 2) + if (!jz4740_pwm_can_use_chn(jz, pwm->hwpwm)) return -EBUSY; snprintf(name, sizeof(name), "timer%u", pwm->hwpwm); |