gpio-only driver operation never clears the SLEEP bit, which can
cause the gpios to become unusable.
Example:
1. user requests first pwm -> driver clears SLEEP bit
2. user frees last pwm -> driver sets SLEEP bit
3. user requests gpio
4. user switches gpio on -> output does not turn on
because SLEEP bit is set
Prevent this behaviour by keeping the SLEEP bit cleared
for the lifetime of the driver instance.
Fixes: bccec89f0a35 ("Allow any of the 16 PWMs to be used as a GPIO")
Signed-off-by: Sven Van Asbroeck <thesve...@googlemail.com>
---
drivers/pwm/pwm-pca9685.c | 18 +++---------------
1 file changed, 3 insertions(+), 15 deletions(-)
diff --git a/drivers/pwm/pwm-pca9685.c b/drivers/pwm/pwm-pca9685.c
index 0cfb357..4b6adaf 100644
--- a/drivers/pwm/pwm-pca9685.c
+++ b/drivers/pwm/pwm-pca9685.c
@@ -79,7 +79,6 @@
struct pca9685 {
struct pwm_chip chip;
struct regmap *regmap;
- int active_cnt;
int duty_ns;
int period_ns;
#if IS_ENABLED(CONFIG_GPIOLIB)
@@ -407,28 +406,14 @@ static int pca9685_pwm_request(struct pwm_chip *chip,
struct pwm_device *pwm)
if (pca9685_pwm_is_gpio(pca, pwm))
return -EBUSY;
- if (pca->active_cnt++ == 0)
- return regmap_update_bits(pca->regmap, PCA9685_MODE1,
- MODE1_SLEEP, 0x0);
-
return 0;
}
-static void pca9685_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
-{
- struct pca9685 *pca = to_pca(chip);
-
- if (--pca->active_cnt == 0)
- regmap_update_bits(pca->regmap, PCA9685_MODE1, MODE1_SLEEP,
- MODE1_SLEEP);
-}
-
static const struct pwm_ops pca9685_pwm_ops = {
.enable = pca9685_pwm_enable,
.disable = pca9685_pwm_disable,
.config = pca9685_pwm_config,
.request = pca9685_pwm_request,
- .free = pca9685_pwm_free,
.owner = THIS_MODULE,
};
@@ -479,6 +464,9 @@ static int pca9685_pwm_probe(struct i2c_client *client,
/* clear all "full off" bits */
regmap_write(pca->regmap, PCA9685_ALL_LED_OFF_L, 0);
regmap_write(pca->regmap, PCA9685_ALL_LED_OFF_H, 0);
+ /* clear the "sleep" bit */
+ regmap_update_bits(pca->regmap, PCA9685_MODE1,
+ MODE1_SLEEP, 0x0);
pca->chip.ops = &pca9685_pwm_ops;
/* add an extra channel for ALL_LED */
--
1.9.1
