diff options
Diffstat (limited to 'drivers/pwm/core.c')
| -rw-r--r-- | drivers/pwm/core.c | 108 |
1 files changed, 94 insertions, 14 deletions
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index 0d66376a83ec..ea2ccf42e814 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -276,7 +276,7 @@ int pwm_round_waveform_might_sleep(struct pwm_device *pwm, struct pwm_waveform * if (IS_ENABLED(CONFIG_PWM_DEBUG) && ret_fromhw > 0) dev_err(&chip->dev, "Unexpected return value from __pwm_round_waveform_fromhw: requested %llu/%llu [+%llu], return value %d\n", - wf_req.duty_length_ns, wf_req.period_length_ns, wf_req.duty_offset_ns, ret_tohw); + wf_req.duty_length_ns, wf_req.period_length_ns, wf_req.duty_offset_ns, ret_fromhw); if (IS_ENABLED(CONFIG_PWM_DEBUG) && (ret_tohw == 0) != pwm_check_rounding(&wf_req, wf)) @@ -497,6 +497,13 @@ static void pwm_apply_debug(struct pwm_device *pwm, return; /* + * If a disabled PWM was requested the result is unspecified, so nothing + * to check. + */ + if (!state->enabled) + return; + + /* * *state was just applied. Read out the hardware state and do some * checks. */ @@ -508,25 +515,31 @@ static void pwm_apply_debug(struct pwm_device *pwm, return; /* + * If the PWM was disabled that's maybe strange but there is nothing + * that can be sensibly checked then. So return early. + */ + if (!s1.enabled) + return; + + /* * The lowlevel driver either ignored .polarity (which is a bug) or as * best effort inverted .polarity and fixed .duty_cycle respectively. * Undo this inversion and fixup for further tests. */ - if (s1.enabled && s1.polarity != state->polarity) { + if (s1.polarity != state->polarity) { s2.polarity = state->polarity; s2.duty_cycle = s1.period - s1.duty_cycle; s2.period = s1.period; - s2.enabled = s1.enabled; + s2.enabled = true; } else { s2 = s1; } if (s2.polarity != state->polarity && - state->duty_cycle < state->period) + s2.duty_cycle < s2.period) dev_warn(pwmchip_parent(chip), ".apply ignored .polarity\n"); - if (state->enabled && s2.enabled && - last->polarity == state->polarity && + if (last->polarity == state->polarity && last->period > s2.period && last->period <= state->period) dev_warn(pwmchip_parent(chip), @@ -537,13 +550,12 @@ static void pwm_apply_debug(struct pwm_device *pwm, * Rounding period up is fine only if duty_cycle is 0 then, because a * flat line doesn't have a characteristic period. */ - if (state->enabled && s2.enabled && state->period < s2.period && s2.duty_cycle) + if (state->period < s2.period && s2.duty_cycle) dev_warn(pwmchip_parent(chip), ".apply is supposed to round down period (requested: %llu, applied: %llu)\n", state->period, s2.period); - if (state->enabled && - last->polarity == state->polarity && + if (last->polarity == state->polarity && last->period == s2.period && last->duty_cycle > s2.duty_cycle && last->duty_cycle <= state->duty_cycle) @@ -553,16 +565,12 @@ static void pwm_apply_debug(struct pwm_device *pwm, s2.duty_cycle, s2.period, last->duty_cycle, last->period); - if (state->enabled && s2.enabled && state->duty_cycle < s2.duty_cycle) + if (state->duty_cycle < s2.duty_cycle) dev_warn(pwmchip_parent(chip), ".apply is supposed to round down duty_cycle (requested: %llu/%llu, applied: %llu/%llu)\n", state->duty_cycle, state->period, s2.duty_cycle, s2.period); - if (!state->enabled && s2.enabled && s2.duty_cycle > 0) - dev_warn(pwmchip_parent(chip), - "requested disabled, but yielded enabled with duty > 0\n"); - /* reapply the state that the driver reported being configured. */ err = chip->ops->apply(chip, pwm, &s1); trace_pwm_apply(pwm, &s1, err); @@ -2383,6 +2391,51 @@ static const struct file_operations pwm_cdev_fileops = { static dev_t pwm_devt; +static int pwm_gpio_request(struct gpio_chip *gc, unsigned int offset) +{ + struct pwm_chip *chip = gpiochip_get_data(gc); + struct pwm_device *pwm; + + pwm = pwm_request_from_chip(chip, offset, "pwm-gpio"); + if (IS_ERR(pwm)) + return PTR_ERR(pwm); + + return 0; +} + +static void pwm_gpio_free(struct gpio_chip *gc, unsigned int offset) +{ + struct pwm_chip *chip = gpiochip_get_data(gc); + + pwm_put(&chip->pwms[offset]); +} + +static int pwm_gpio_get_direction(struct gpio_chip *gc, unsigned int offset) +{ + return GPIO_LINE_DIRECTION_OUT; +} + +static int pwm_gpio_set(struct gpio_chip *gc, unsigned int offset, int value) +{ + struct pwm_chip *chip = gpiochip_get_data(gc); + struct pwm_device *pwm = &chip->pwms[offset]; + int ret; + struct pwm_waveform wf = { + .period_length_ns = 1, + }; + + ret = pwm_round_waveform_might_sleep(pwm, &wf); + if (ret < 0) + return ret; + + if (value) + wf.duty_length_ns = wf.period_length_ns; + else + wf.duty_length_ns = 0; + + return pwm_set_waveform_might_sleep(pwm, &wf, true); +} + /** * __pwmchip_add() - register a new PWM chip * @chip: the PWM chip to add @@ -2449,9 +2502,33 @@ int __pwmchip_add(struct pwm_chip *chip, struct module *owner) if (ret) goto err_device_add; + if (IS_ENABLED(CONFIG_PWM_PROVIDE_GPIO) && chip->ops->write_waveform) { + struct device *parent = pwmchip_parent(chip); + + chip->gpio = (typeof(chip->gpio)){ + .label = dev_name(parent), + .parent = parent, + .request = pwm_gpio_request, + .free = pwm_gpio_free, + .get_direction = pwm_gpio_get_direction, + .set = pwm_gpio_set, + .base = -1, + .ngpio = chip->npwm, + .can_sleep = true, + }; + + ret = gpiochip_add_data(&chip->gpio, chip); + if (ret) + goto err_gpiochip_add; + } + return 0; +err_gpiochip_add: + + cdev_device_del(&chip->cdev, &chip->dev); err_device_add: + scoped_guard(pwmchip, chip) chip->operational = false; @@ -2472,6 +2549,9 @@ EXPORT_SYMBOL_GPL(__pwmchip_add); */ void pwmchip_remove(struct pwm_chip *chip) { + if (IS_ENABLED(CONFIG_PWM_PROVIDE_GPIO) && chip->ops->write_waveform) + gpiochip_remove(&chip->gpio); + pwmchip_sysfs_unexport(chip); scoped_guard(mutex, &pwm_lock) { |