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authorPaul Cercueil <paul@crapouillou.net>2020-03-23 15:24:21 +0100
committerThierry Reding <thierry.reding@gmail.com>2020-03-30 18:03:10 +0200
commita2005fc791798f40cc9895b6abda8fbc7a168174 (patch)
tree806a24d62ee0d13e18722fb14856f304f487b4ab /drivers/pwm
parentc2693514a0a1ec3abcb4673775af3edc797e8a07 (diff)
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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.c19
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);