pwm: Move contents of sysfs.c into core.c
With the upcoming restructuring having all in a single file simplifies things a bit. The relevant and somewhat visible changes are: - Some dropped prototypes from include/linux/pwm.h that were only necessary that core.c has a declaration of the symbols defined in sysfs.c. The respective functions are static now. - The pwm class now also exists if CONFIG_SYSFS isn't enabled. Having CONFIG_SYSFS is not very relevant today, but even without it the class and device stuff still provides lifetime tracking. - Both files had an initcall, these are merged into a single one now. Instead of a big #ifdef block for CONFIG_DEBUG_FS, a single if (IS_ENABLED(CONFIG_DEBUG_FS)) is used now. This increases compile coverage a bit and is a tad nicer on the eyes. Link: https://lore.kernel.org/r/9e2d39a5280d7dda5bfc6682a8aef510148635b2.1710670958.git.u.kleine-koenig@pengutronix.de Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
This commit is contained in:
Uwe Kleine-König
parent
b40ac0e176
commit
e9cc807f87
@ -29,10 +29,6 @@ menuconfig PWM
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if PWM
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config PWM_SYSFS
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bool
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default y if SYSFS
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config PWM_DEBUG
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bool "PWM lowlevel drivers additional checks and debug messages"
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depends on DEBUG_KERNEL
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@ -1,6 +1,5 @@
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# SPDX-License-Identifier: GPL-2.0
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obj-$(CONFIG_PWM) += core.o
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obj-$(CONFIG_PWM_SYSFS) += sysfs.o
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obj-$(CONFIG_PWM_AB8500) += pwm-ab8500.o
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obj-$(CONFIG_PWM_APPLE) += pwm-apple.o
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obj-$(CONFIG_PWM_ATMEL) += pwm-atmel.o
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@ -454,6 +454,535 @@ of_pwm_single_xlate(struct pwm_chip *chip, const struct of_phandle_args *args)
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}
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EXPORT_SYMBOL_GPL(of_pwm_single_xlate);
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struct pwm_export {
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struct device pwm_dev;
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struct pwm_device *pwm;
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struct mutex lock;
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struct pwm_state suspend;
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};
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static inline struct pwm_chip *pwmchip_from_dev(struct device *pwmchip_dev)
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{
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return dev_get_drvdata(pwmchip_dev);
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}
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static inline struct pwm_export *pwmexport_from_dev(struct device *pwm_dev)
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{
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return container_of(pwm_dev, struct pwm_export, pwm_dev);
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}
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static inline struct pwm_device *pwm_from_dev(struct device *pwm_dev)
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{
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struct pwm_export *export = pwmexport_from_dev(pwm_dev);
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return export->pwm;
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}
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static ssize_t period_show(struct device *pwm_dev,
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struct device_attribute *attr,
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char *buf)
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{
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const struct pwm_device *pwm = pwm_from_dev(pwm_dev);
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struct pwm_state state;
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pwm_get_state(pwm, &state);
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return sysfs_emit(buf, "%llu\n", state.period);
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}
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static ssize_t period_store(struct device *pwm_dev,
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struct device_attribute *attr,
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const char *buf, size_t size)
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{
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struct pwm_export *export = pwmexport_from_dev(pwm_dev);
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struct pwm_device *pwm = export->pwm;
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struct pwm_state state;
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u64 val;
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int ret;
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ret = kstrtou64(buf, 0, &val);
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if (ret)
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return ret;
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mutex_lock(&export->lock);
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pwm_get_state(pwm, &state);
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state.period = val;
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ret = pwm_apply_might_sleep(pwm, &state);
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mutex_unlock(&export->lock);
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return ret ? : size;
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}
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static ssize_t duty_cycle_show(struct device *pwm_dev,
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struct device_attribute *attr,
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char *buf)
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{
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const struct pwm_device *pwm = pwm_from_dev(pwm_dev);
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struct pwm_state state;
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pwm_get_state(pwm, &state);
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return sysfs_emit(buf, "%llu\n", state.duty_cycle);
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}
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static ssize_t duty_cycle_store(struct device *pwm_dev,
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struct device_attribute *attr,
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const char *buf, size_t size)
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{
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struct pwm_export *export = pwmexport_from_dev(pwm_dev);
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struct pwm_device *pwm = export->pwm;
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struct pwm_state state;
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u64 val;
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int ret;
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ret = kstrtou64(buf, 0, &val);
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if (ret)
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return ret;
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mutex_lock(&export->lock);
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pwm_get_state(pwm, &state);
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state.duty_cycle = val;
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ret = pwm_apply_might_sleep(pwm, &state);
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mutex_unlock(&export->lock);
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return ret ? : size;
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}
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static ssize_t enable_show(struct device *pwm_dev,
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struct device_attribute *attr,
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char *buf)
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{
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const struct pwm_device *pwm = pwm_from_dev(pwm_dev);
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struct pwm_state state;
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pwm_get_state(pwm, &state);
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return sysfs_emit(buf, "%d\n", state.enabled);
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}
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static ssize_t enable_store(struct device *pwm_dev,
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struct device_attribute *attr,
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const char *buf, size_t size)
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{
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struct pwm_export *export = pwmexport_from_dev(pwm_dev);
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struct pwm_device *pwm = export->pwm;
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struct pwm_state state;
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int val, ret;
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ret = kstrtoint(buf, 0, &val);
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if (ret)
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return ret;
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mutex_lock(&export->lock);
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pwm_get_state(pwm, &state);
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switch (val) {
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case 0:
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state.enabled = false;
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break;
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case 1:
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state.enabled = true;
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break;
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default:
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ret = -EINVAL;
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goto unlock;
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}
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ret = pwm_apply_might_sleep(pwm, &state);
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unlock:
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mutex_unlock(&export->lock);
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return ret ? : size;
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}
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static ssize_t polarity_show(struct device *pwm_dev,
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struct device_attribute *attr,
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char *buf)
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{
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const struct pwm_device *pwm = pwm_from_dev(pwm_dev);
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const char *polarity = "unknown";
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struct pwm_state state;
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pwm_get_state(pwm, &state);
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switch (state.polarity) {
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case PWM_POLARITY_NORMAL:
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polarity = "normal";
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break;
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case PWM_POLARITY_INVERSED:
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polarity = "inversed";
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break;
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}
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return sysfs_emit(buf, "%s\n", polarity);
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}
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static ssize_t polarity_store(struct device *pwm_dev,
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struct device_attribute *attr,
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const char *buf, size_t size)
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{
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struct pwm_export *export = pwmexport_from_dev(pwm_dev);
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struct pwm_device *pwm = export->pwm;
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enum pwm_polarity polarity;
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struct pwm_state state;
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int ret;
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if (sysfs_streq(buf, "normal"))
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polarity = PWM_POLARITY_NORMAL;
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else if (sysfs_streq(buf, "inversed"))
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polarity = PWM_POLARITY_INVERSED;
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else
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return -EINVAL;
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mutex_lock(&export->lock);
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pwm_get_state(pwm, &state);
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state.polarity = polarity;
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ret = pwm_apply_might_sleep(pwm, &state);
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mutex_unlock(&export->lock);
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return ret ? : size;
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}
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static ssize_t capture_show(struct device *pwm_dev,
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struct device_attribute *attr,
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char *buf)
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{
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struct pwm_device *pwm = pwm_from_dev(pwm_dev);
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struct pwm_capture result;
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int ret;
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ret = pwm_capture(pwm, &result, jiffies_to_msecs(HZ));
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if (ret)
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return ret;
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return sysfs_emit(buf, "%u %u\n", result.period, result.duty_cycle);
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}
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static DEVICE_ATTR_RW(period);
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static DEVICE_ATTR_RW(duty_cycle);
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static DEVICE_ATTR_RW(enable);
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static DEVICE_ATTR_RW(polarity);
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static DEVICE_ATTR_RO(capture);
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static struct attribute *pwm_attrs[] = {
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&dev_attr_period.attr,
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&dev_attr_duty_cycle.attr,
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&dev_attr_enable.attr,
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&dev_attr_polarity.attr,
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&dev_attr_capture.attr,
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NULL
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};
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ATTRIBUTE_GROUPS(pwm);
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static void pwm_export_release(struct device *pwm_dev)
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{
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struct pwm_export *export = pwmexport_from_dev(pwm_dev);
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kfree(export);
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}
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static int pwm_export_child(struct device *pwmchip_dev, struct pwm_device *pwm)
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{
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struct pwm_export *export;
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char *pwm_prop[2];
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int ret;
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if (test_and_set_bit(PWMF_EXPORTED, &pwm->flags))
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return -EBUSY;
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export = kzalloc(sizeof(*export), GFP_KERNEL);
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if (!export) {
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clear_bit(PWMF_EXPORTED, &pwm->flags);
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return -ENOMEM;
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}
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export->pwm = pwm;
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mutex_init(&export->lock);
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export->pwm_dev.release = pwm_export_release;
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export->pwm_dev.parent = pwmchip_dev;
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export->pwm_dev.devt = MKDEV(0, 0);
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export->pwm_dev.groups = pwm_groups;
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dev_set_name(&export->pwm_dev, "pwm%u", pwm->hwpwm);
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ret = device_register(&export->pwm_dev);
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if (ret) {
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clear_bit(PWMF_EXPORTED, &pwm->flags);
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put_device(&export->pwm_dev);
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export = NULL;
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return ret;
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}
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pwm_prop[0] = kasprintf(GFP_KERNEL, "EXPORT=pwm%u", pwm->hwpwm);
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pwm_prop[1] = NULL;
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kobject_uevent_env(&pwmchip_dev->kobj, KOBJ_CHANGE, pwm_prop);
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kfree(pwm_prop[0]);
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return 0;
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}
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static int pwm_unexport_match(struct device *pwm_dev, void *data)
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{
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return pwm_from_dev(pwm_dev) == data;
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}
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static int pwm_unexport_child(struct device *pwmchip_dev, struct pwm_device *pwm)
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{
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struct device *pwm_dev;
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char *pwm_prop[2];
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if (!test_and_clear_bit(PWMF_EXPORTED, &pwm->flags))
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return -ENODEV;
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pwm_dev = device_find_child(pwmchip_dev, pwm, pwm_unexport_match);
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if (!pwm_dev)
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return -ENODEV;
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pwm_prop[0] = kasprintf(GFP_KERNEL, "UNEXPORT=pwm%u", pwm->hwpwm);
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pwm_prop[1] = NULL;
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kobject_uevent_env(&pwmchip_dev->kobj, KOBJ_CHANGE, pwm_prop);
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kfree(pwm_prop[0]);
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/* for device_find_child() */
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put_device(pwm_dev);
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device_unregister(pwm_dev);
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pwm_put(pwm);
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return 0;
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}
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static ssize_t export_store(struct device *pwmchip_dev,
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struct device_attribute *attr,
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const char *buf, size_t len)
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{
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struct pwm_chip *chip = pwmchip_from_dev(pwmchip_dev);
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struct pwm_device *pwm;
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unsigned int hwpwm;
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int ret;
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ret = kstrtouint(buf, 0, &hwpwm);
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if (ret < 0)
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return ret;
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if (hwpwm >= chip->npwm)
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return -ENODEV;
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pwm = pwm_request_from_chip(chip, hwpwm, "sysfs");
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if (IS_ERR(pwm))
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return PTR_ERR(pwm);
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ret = pwm_export_child(pwmchip_dev, pwm);
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if (ret < 0)
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pwm_put(pwm);
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return ret ? : len;
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}
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static DEVICE_ATTR_WO(export);
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static ssize_t unexport_store(struct device *pwmchip_dev,
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struct device_attribute *attr,
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const char *buf, size_t len)
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{
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struct pwm_chip *chip = pwmchip_from_dev(pwmchip_dev);
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unsigned int hwpwm;
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int ret;
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ret = kstrtouint(buf, 0, &hwpwm);
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if (ret < 0)
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return ret;
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if (hwpwm >= chip->npwm)
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return -ENODEV;
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ret = pwm_unexport_child(pwmchip_dev, &chip->pwms[hwpwm]);
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return ret ? : len;
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}
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static DEVICE_ATTR_WO(unexport);
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static ssize_t npwm_show(struct device *pwmchip_dev, struct device_attribute *attr,
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char *buf)
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{
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const struct pwm_chip *chip = pwmchip_from_dev(pwmchip_dev);
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return sysfs_emit(buf, "%u\n", chip->npwm);
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}
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static DEVICE_ATTR_RO(npwm);
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static struct attribute *pwm_chip_attrs[] = {
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&dev_attr_export.attr,
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&dev_attr_unexport.attr,
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&dev_attr_npwm.attr,
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NULL,
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};
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ATTRIBUTE_GROUPS(pwm_chip);
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/* takes export->lock on success */
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static struct pwm_export *pwm_class_get_state(struct device *pwmchip_dev,
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struct pwm_device *pwm,
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struct pwm_state *state)
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{
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struct device *pwm_dev;
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struct pwm_export *export;
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if (!test_bit(PWMF_EXPORTED, &pwm->flags))
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return NULL;
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pwm_dev = device_find_child(pwmchip_dev, pwm, pwm_unexport_match);
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if (!pwm_dev)
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return NULL;
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export = pwmexport_from_dev(pwm_dev);
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put_device(pwm_dev); /* for device_find_child() */
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mutex_lock(&export->lock);
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pwm_get_state(pwm, state);
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return export;
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}
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static int pwm_class_apply_state(struct pwm_export *export,
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struct pwm_device *pwm,
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struct pwm_state *state)
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{
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int ret = pwm_apply_might_sleep(pwm, state);
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/* release lock taken in pwm_class_get_state */
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mutex_unlock(&export->lock);
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return ret;
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}
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static int pwm_class_resume_npwm(struct device *pwmchip_dev, unsigned int npwm)
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{
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struct pwm_chip *chip = pwmchip_from_dev(pwmchip_dev);
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unsigned int i;
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int ret = 0;
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for (i = 0; i < npwm; i++) {
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struct pwm_device *pwm = &chip->pwms[i];
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struct pwm_state state;
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struct pwm_export *export;
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export = pwm_class_get_state(pwmchip_dev, pwm, &state);
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if (!export)
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continue;
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/* If pwmchip was not enabled before suspend, do nothing. */
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if (!export->suspend.enabled) {
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/* release lock taken in pwm_class_get_state */
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mutex_unlock(&export->lock);
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continue;
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}
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state.enabled = export->suspend.enabled;
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ret = pwm_class_apply_state(export, pwm, &state);
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if (ret < 0)
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break;
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}
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return ret;
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}
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static int pwm_class_suspend(struct device *pwmchip_dev)
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{
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struct pwm_chip *chip = pwmchip_from_dev(pwmchip_dev);
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unsigned int i;
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int ret = 0;
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for (i = 0; i < chip->npwm; i++) {
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struct pwm_device *pwm = &chip->pwms[i];
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struct pwm_state state;
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struct pwm_export *export;
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export = pwm_class_get_state(pwmchip_dev, pwm, &state);
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if (!export)
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continue;
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/*
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* If pwmchip was not enabled before suspend, save
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* state for resume time and do nothing else.
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*/
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export->suspend = state;
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if (!state.enabled) {
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/* release lock taken in pwm_class_get_state */
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mutex_unlock(&export->lock);
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continue;
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}
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state.enabled = false;
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ret = pwm_class_apply_state(export, pwm, &state);
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if (ret < 0) {
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/*
|
||||
* roll back the PWM devices that were disabled by
|
||||
* this suspend function.
|
||||
*/
|
||||
pwm_class_resume_npwm(pwmchip_dev, i);
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int pwm_class_resume(struct device *pwmchip_dev)
|
||||
{
|
||||
struct pwm_chip *chip = pwmchip_from_dev(pwmchip_dev);
|
||||
|
||||
return pwm_class_resume_npwm(pwmchip_dev, chip->npwm);
|
||||
}
|
||||
|
||||
static DEFINE_SIMPLE_DEV_PM_OPS(pwm_class_pm_ops, pwm_class_suspend, pwm_class_resume);
|
||||
|
||||
static struct class pwm_class = {
|
||||
.name = "pwm",
|
||||
.dev_groups = pwm_chip_groups,
|
||||
.pm = pm_sleep_ptr(&pwm_class_pm_ops),
|
||||
};
|
||||
|
||||
static int pwmchip_sysfs_match(struct device *pwmchip_dev, const void *data)
|
||||
{
|
||||
return pwmchip_from_dev(pwmchip_dev) == data;
|
||||
}
|
||||
|
||||
static void pwmchip_sysfs_export(struct pwm_chip *chip)
|
||||
{
|
||||
struct device *pwmchip_dev;
|
||||
|
||||
/*
|
||||
* If device_create() fails the pwm_chip is still usable by
|
||||
* the kernel it's just not exported.
|
||||
*/
|
||||
pwmchip_dev = device_create(&pwm_class, pwmchip_parent(chip), MKDEV(0, 0), chip,
|
||||
"pwmchip%d", chip->id);
|
||||
if (IS_ERR(pwmchip_dev)) {
|
||||
dev_warn(pwmchip_parent(chip),
|
||||
"device_create failed for pwm_chip sysfs export\n");
|
||||
}
|
||||
}
|
||||
|
||||
static void pwmchip_sysfs_unexport(struct pwm_chip *chip)
|
||||
{
|
||||
struct device *pwmchip_dev;
|
||||
unsigned int i;
|
||||
|
||||
pwmchip_dev = class_find_device(&pwm_class, NULL, chip,
|
||||
pwmchip_sysfs_match);
|
||||
if (!pwmchip_dev)
|
||||
return;
|
||||
|
||||
for (i = 0; i < chip->npwm; i++) {
|
||||
struct pwm_device *pwm = &chip->pwms[i];
|
||||
|
||||
if (test_bit(PWMF_EXPORTED, &pwm->flags))
|
||||
pwm_unexport_child(pwmchip_dev, pwm);
|
||||
}
|
||||
|
||||
put_device(pwmchip_dev);
|
||||
device_unregister(pwmchip_dev);
|
||||
}
|
||||
|
||||
#define PWMCHIP_ALIGN ARCH_DMA_MINALIGN
|
||||
|
||||
static void *pwmchip_priv(struct pwm_chip *chip)
|
||||
@ -1086,7 +1615,6 @@ struct pwm_device *devm_fwnode_pwm_get(struct device *dev,
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(devm_fwnode_pwm_get);
|
||||
|
||||
#ifdef CONFIG_DEBUG_FS
|
||||
static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s)
|
||||
{
|
||||
unsigned int i;
|
||||
@ -1171,11 +1699,11 @@ static const struct seq_operations pwm_debugfs_sops = {
|
||||
|
||||
DEFINE_SEQ_ATTRIBUTE(pwm_debugfs);
|
||||
|
||||
static int __init pwm_debugfs_init(void)
|
||||
static int __init pwm_init(void)
|
||||
{
|
||||
debugfs_create_file("pwm", 0444, NULL, NULL, &pwm_debugfs_fops);
|
||||
if (IS_ENABLED(CONFIG_DEBUG_FS))
|
||||
debugfs_create_file("pwm", 0444, NULL, NULL, &pwm_debugfs_fops);
|
||||
|
||||
return 0;
|
||||
return class_register(&pwm_class);
|
||||
}
|
||||
subsys_initcall(pwm_debugfs_init);
|
||||
#endif /* CONFIG_DEBUG_FS */
|
||||
subsys_initcall(pwm_init);
|
||||
|
||||
@ -1,550 +0,0 @@
|
||||
// SPDX-License-Identifier: GPL-2.0-or-later
|
||||
/*
|
||||
* A simple sysfs interface for the generic PWM framework
|
||||
*
|
||||
* Copyright (C) 2013 H Hartley Sweeten <hsweeten@visionengravers.com>
|
||||
*
|
||||
* Based on previous work by Lars Poeschel <poeschel@lemonage.de>
|
||||
*/
|
||||
|
||||
#include <linux/device.h>
|
||||
#include <linux/mutex.h>
|
||||
#include <linux/err.h>
|
||||
#include <linux/slab.h>
|
||||
#include <linux/kdev_t.h>
|
||||
#include <linux/pwm.h>
|
||||
|
||||
struct pwm_export {
|
||||
struct device pwm_dev;
|
||||
struct pwm_device *pwm;
|
||||
struct mutex lock;
|
||||
struct pwm_state suspend;
|
||||
};
|
||||
|
||||
static inline struct pwm_chip *pwmchip_from_dev(struct device *pwmchip_dev)
|
||||
{
|
||||
return dev_get_drvdata(pwmchip_dev);
|
||||
}
|
||||
|
||||
static inline struct pwm_export *pwmexport_from_dev(struct device *pwm_dev)
|
||||
{
|
||||
return container_of(pwm_dev, struct pwm_export, pwm_dev);
|
||||
}
|
||||
|
||||
static inline struct pwm_device *pwm_from_dev(struct device *pwm_dev)
|
||||
{
|
||||
struct pwm_export *export = pwmexport_from_dev(pwm_dev);
|
||||
|
||||
return export->pwm;
|
||||
}
|
||||
|
||||
static ssize_t period_show(struct device *pwm_dev,
|
||||
struct device_attribute *attr,
|
||||
char *buf)
|
||||
{
|
||||
const struct pwm_device *pwm = pwm_from_dev(pwm_dev);
|
||||
struct pwm_state state;
|
||||
|
||||
pwm_get_state(pwm, &state);
|
||||
|
||||
return sysfs_emit(buf, "%llu\n", state.period);
|
||||
}
|
||||
|
||||
static ssize_t period_store(struct device *pwm_dev,
|
||||
struct device_attribute *attr,
|
||||
const char *buf, size_t size)
|
||||
{
|
||||
struct pwm_export *export = pwmexport_from_dev(pwm_dev);
|
||||
struct pwm_device *pwm = export->pwm;
|
||||
struct pwm_state state;
|
||||
u64 val;
|
||||
int ret;
|
||||
|
||||
ret = kstrtou64(buf, 0, &val);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
mutex_lock(&export->lock);
|
||||
pwm_get_state(pwm, &state);
|
||||
state.period = val;
|
||||
ret = pwm_apply_might_sleep(pwm, &state);
|
||||
mutex_unlock(&export->lock);
|
||||
|
||||
return ret ? : size;
|
||||
}
|
||||
|
||||
static ssize_t duty_cycle_show(struct device *pwm_dev,
|
||||
struct device_attribute *attr,
|
||||
char *buf)
|
||||
{
|
||||
const struct pwm_device *pwm = pwm_from_dev(pwm_dev);
|
||||
struct pwm_state state;
|
||||
|
||||
pwm_get_state(pwm, &state);
|
||||
|
||||
return sysfs_emit(buf, "%llu\n", state.duty_cycle);
|
||||
}
|
||||
|
||||
static ssize_t duty_cycle_store(struct device *pwm_dev,
|
||||
struct device_attribute *attr,
|
||||
const char *buf, size_t size)
|
||||
{
|
||||
struct pwm_export *export = pwmexport_from_dev(pwm_dev);
|
||||
struct pwm_device *pwm = export->pwm;
|
||||
struct pwm_state state;
|
||||
u64 val;
|
||||
int ret;
|
||||
|
||||
ret = kstrtou64(buf, 0, &val);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
mutex_lock(&export->lock);
|
||||
pwm_get_state(pwm, &state);
|
||||
state.duty_cycle = val;
|
||||
ret = pwm_apply_might_sleep(pwm, &state);
|
||||
mutex_unlock(&export->lock);
|
||||
|
||||
return ret ? : size;
|
||||
}
|
||||
|
||||
static ssize_t enable_show(struct device *pwm_dev,
|
||||
struct device_attribute *attr,
|
||||
char *buf)
|
||||
{
|
||||
const struct pwm_device *pwm = pwm_from_dev(pwm_dev);
|
||||
struct pwm_state state;
|
||||
|
||||
pwm_get_state(pwm, &state);
|
||||
|
||||
return sysfs_emit(buf, "%d\n", state.enabled);
|
||||
}
|
||||
|
||||
static ssize_t enable_store(struct device *pwm_dev,
|
||||
struct device_attribute *attr,
|
||||
const char *buf, size_t size)
|
||||
{
|
||||
struct pwm_export *export = pwmexport_from_dev(pwm_dev);
|
||||
struct pwm_device *pwm = export->pwm;
|
||||
struct pwm_state state;
|
||||
int val, ret;
|
||||
|
||||
ret = kstrtoint(buf, 0, &val);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
mutex_lock(&export->lock);
|
||||
|
||||
pwm_get_state(pwm, &state);
|
||||
|
||||
switch (val) {
|
||||
case 0:
|
||||
state.enabled = false;
|
||||
break;
|
||||
case 1:
|
||||
state.enabled = true;
|
||||
break;
|
||||
default:
|
||||
ret = -EINVAL;
|
||||
goto unlock;
|
||||
}
|
||||
|
||||
ret = pwm_apply_might_sleep(pwm, &state);
|
||||
|
||||
unlock:
|
||||
mutex_unlock(&export->lock);
|
||||
return ret ? : size;
|
||||
}
|
||||
|
||||
static ssize_t polarity_show(struct device *pwm_dev,
|
||||
struct device_attribute *attr,
|
||||
char *buf)
|
||||
{
|
||||
const struct pwm_device *pwm = pwm_from_dev(pwm_dev);
|
||||
const char *polarity = "unknown";
|
||||
struct pwm_state state;
|
||||
|
||||
pwm_get_state(pwm, &state);
|
||||
|
||||
switch (state.polarity) {
|
||||
case PWM_POLARITY_NORMAL:
|
||||
polarity = "normal";
|
||||
break;
|
||||
|
||||
case PWM_POLARITY_INVERSED:
|
||||
polarity = "inversed";
|
||||
break;
|
||||
}
|
||||
|
||||
return sysfs_emit(buf, "%s\n", polarity);
|
||||
}
|
||||
|
||||
static ssize_t polarity_store(struct device *pwm_dev,
|
||||
struct device_attribute *attr,
|
||||
const char *buf, size_t size)
|
||||
{
|
||||
struct pwm_export *export = pwmexport_from_dev(pwm_dev);
|
||||
struct pwm_device *pwm = export->pwm;
|
||||
enum pwm_polarity polarity;
|
||||
struct pwm_state state;
|
||||
int ret;
|
||||
|
||||
if (sysfs_streq(buf, "normal"))
|
||||
polarity = PWM_POLARITY_NORMAL;
|
||||
else if (sysfs_streq(buf, "inversed"))
|
||||
polarity = PWM_POLARITY_INVERSED;
|
||||
else
|
||||
return -EINVAL;
|
||||
|
||||
mutex_lock(&export->lock);
|
||||
pwm_get_state(pwm, &state);
|
||||
state.polarity = polarity;
|
||||
ret = pwm_apply_might_sleep(pwm, &state);
|
||||
mutex_unlock(&export->lock);
|
||||
|
||||
return ret ? : size;
|
||||
}
|
||||
|
||||
static ssize_t capture_show(struct device *pwm_dev,
|
||||
struct device_attribute *attr,
|
||||
char *buf)
|
||||
{
|
||||
struct pwm_device *pwm = pwm_from_dev(pwm_dev);
|
||||
struct pwm_capture result;
|
||||
int ret;
|
||||
|
||||
ret = pwm_capture(pwm, &result, jiffies_to_msecs(HZ));
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
return sysfs_emit(buf, "%u %u\n", result.period, result.duty_cycle);
|
||||
}
|
||||
|
||||
static DEVICE_ATTR_RW(period);
|
||||
static DEVICE_ATTR_RW(duty_cycle);
|
||||
static DEVICE_ATTR_RW(enable);
|
||||
static DEVICE_ATTR_RW(polarity);
|
||||
static DEVICE_ATTR_RO(capture);
|
||||
|
||||
static struct attribute *pwm_attrs[] = {
|
||||
&dev_attr_period.attr,
|
||||
&dev_attr_duty_cycle.attr,
|
||||
&dev_attr_enable.attr,
|
||||
&dev_attr_polarity.attr,
|
||||
&dev_attr_capture.attr,
|
||||
NULL
|
||||
};
|
||||
ATTRIBUTE_GROUPS(pwm);
|
||||
|
||||
static void pwm_export_release(struct device *pwm_dev)
|
||||
{
|
||||
struct pwm_export *export = pwmexport_from_dev(pwm_dev);
|
||||
|
||||
kfree(export);
|
||||
}
|
||||
|
||||
static int pwm_export_child(struct device *pwmchip_dev, struct pwm_device *pwm)
|
||||
{
|
||||
struct pwm_export *export;
|
||||
char *pwm_prop[2];
|
||||
int ret;
|
||||
|
||||
if (test_and_set_bit(PWMF_EXPORTED, &pwm->flags))
|
||||
return -EBUSY;
|
||||
|
||||
export = kzalloc(sizeof(*export), GFP_KERNEL);
|
||||
if (!export) {
|
||||
clear_bit(PWMF_EXPORTED, &pwm->flags);
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
export->pwm = pwm;
|
||||
mutex_init(&export->lock);
|
||||
|
||||
export->pwm_dev.release = pwm_export_release;
|
||||
export->pwm_dev.parent = pwmchip_dev;
|
||||
export->pwm_dev.devt = MKDEV(0, 0);
|
||||
export->pwm_dev.groups = pwm_groups;
|
||||
dev_set_name(&export->pwm_dev, "pwm%u", pwm->hwpwm);
|
||||
|
||||
ret = device_register(&export->pwm_dev);
|
||||
if (ret) {
|
||||
clear_bit(PWMF_EXPORTED, &pwm->flags);
|
||||
put_device(&export->pwm_dev);
|
||||
export = NULL;
|
||||
return ret;
|
||||
}
|
||||
pwm_prop[0] = kasprintf(GFP_KERNEL, "EXPORT=pwm%u", pwm->hwpwm);
|
||||
pwm_prop[1] = NULL;
|
||||
kobject_uevent_env(&pwmchip_dev->kobj, KOBJ_CHANGE, pwm_prop);
|
||||
kfree(pwm_prop[0]);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int pwm_unexport_match(struct device *pwm_dev, void *data)
|
||||
{
|
||||
return pwm_from_dev(pwm_dev) == data;
|
||||
}
|
||||
|
||||
static int pwm_unexport_child(struct device *pwmchip_dev, struct pwm_device *pwm)
|
||||
{
|
||||
struct device *pwm_dev;
|
||||
char *pwm_prop[2];
|
||||
|
||||
if (!test_and_clear_bit(PWMF_EXPORTED, &pwm->flags))
|
||||
return -ENODEV;
|
||||
|
||||
pwm_dev = device_find_child(pwmchip_dev, pwm, pwm_unexport_match);
|
||||
if (!pwm_dev)
|
||||
return -ENODEV;
|
||||
|
||||
pwm_prop[0] = kasprintf(GFP_KERNEL, "UNEXPORT=pwm%u", pwm->hwpwm);
|
||||
pwm_prop[1] = NULL;
|
||||
kobject_uevent_env(&pwmchip_dev->kobj, KOBJ_CHANGE, pwm_prop);
|
||||
kfree(pwm_prop[0]);
|
||||
|
||||
/* for device_find_child() */
|
||||
put_device(pwm_dev);
|
||||
device_unregister(pwm_dev);
|
||||
pwm_put(pwm);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static ssize_t export_store(struct device *pwmchip_dev,
|
||||
struct device_attribute *attr,
|
||||
const char *buf, size_t len)
|
||||
{
|
||||
struct pwm_chip *chip = pwmchip_from_dev(pwmchip_dev);
|
||||
struct pwm_device *pwm;
|
||||
unsigned int hwpwm;
|
||||
int ret;
|
||||
|
||||
ret = kstrtouint(buf, 0, &hwpwm);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
if (hwpwm >= chip->npwm)
|
||||
return -ENODEV;
|
||||
|
||||
pwm = pwm_request_from_chip(chip, hwpwm, "sysfs");
|
||||
if (IS_ERR(pwm))
|
||||
return PTR_ERR(pwm);
|
||||
|
||||
ret = pwm_export_child(pwmchip_dev, pwm);
|
||||
if (ret < 0)
|
||||
pwm_put(pwm);
|
||||
|
||||
return ret ? : len;
|
||||
}
|
||||
static DEVICE_ATTR_WO(export);
|
||||
|
||||
static ssize_t unexport_store(struct device *pwmchip_dev,
|
||||
struct device_attribute *attr,
|
||||
const char *buf, size_t len)
|
||||
{
|
||||
struct pwm_chip *chip = pwmchip_from_dev(pwmchip_dev);
|
||||
unsigned int hwpwm;
|
||||
int ret;
|
||||
|
||||
ret = kstrtouint(buf, 0, &hwpwm);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
if (hwpwm >= chip->npwm)
|
||||
return -ENODEV;
|
||||
|
||||
ret = pwm_unexport_child(pwmchip_dev, &chip->pwms[hwpwm]);
|
||||
|
||||
return ret ? : len;
|
||||
}
|
||||
static DEVICE_ATTR_WO(unexport);
|
||||
|
||||
static ssize_t npwm_show(struct device *pwmchip_dev, struct device_attribute *attr,
|
||||
char *buf)
|
||||
{
|
||||
const struct pwm_chip *chip = pwmchip_from_dev(pwmchip_dev);
|
||||
|
||||
return sysfs_emit(buf, "%u\n", chip->npwm);
|
||||
}
|
||||
static DEVICE_ATTR_RO(npwm);
|
||||
|
||||
static struct attribute *pwm_chip_attrs[] = {
|
||||
&dev_attr_export.attr,
|
||||
&dev_attr_unexport.attr,
|
||||
&dev_attr_npwm.attr,
|
||||
NULL,
|
||||
};
|
||||
ATTRIBUTE_GROUPS(pwm_chip);
|
||||
|
||||
/* takes export->lock on success */
|
||||
static struct pwm_export *pwm_class_get_state(struct device *pwmchip_dev,
|
||||
struct pwm_device *pwm,
|
||||
struct pwm_state *state)
|
||||
{
|
||||
struct device *pwm_dev;
|
||||
struct pwm_export *export;
|
||||
|
||||
if (!test_bit(PWMF_EXPORTED, &pwm->flags))
|
||||
return NULL;
|
||||
|
||||
pwm_dev = device_find_child(pwmchip_dev, pwm, pwm_unexport_match);
|
||||
if (!pwm_dev)
|
||||
return NULL;
|
||||
|
||||
export = pwmexport_from_dev(pwm_dev);
|
||||
put_device(pwm_dev); /* for device_find_child() */
|
||||
|
||||
mutex_lock(&export->lock);
|
||||
pwm_get_state(pwm, state);
|
||||
|
||||
return export;
|
||||
}
|
||||
|
||||
static int pwm_class_apply_state(struct pwm_export *export,
|
||||
struct pwm_device *pwm,
|
||||
struct pwm_state *state)
|
||||
{
|
||||
int ret = pwm_apply_might_sleep(pwm, state);
|
||||
|
||||
/* release lock taken in pwm_class_get_state */
|
||||
mutex_unlock(&export->lock);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int pwm_class_resume_npwm(struct device *pwmchip_dev, unsigned int npwm)
|
||||
{
|
||||
struct pwm_chip *chip = pwmchip_from_dev(pwmchip_dev);
|
||||
unsigned int i;
|
||||
int ret = 0;
|
||||
|
||||
for (i = 0; i < npwm; i++) {
|
||||
struct pwm_device *pwm = &chip->pwms[i];
|
||||
struct pwm_state state;
|
||||
struct pwm_export *export;
|
||||
|
||||
export = pwm_class_get_state(pwmchip_dev, pwm, &state);
|
||||
if (!export)
|
||||
continue;
|
||||
|
||||
/* If pwmchip was not enabled before suspend, do nothing. */
|
||||
if (!export->suspend.enabled) {
|
||||
/* release lock taken in pwm_class_get_state */
|
||||
mutex_unlock(&export->lock);
|
||||
continue;
|
||||
}
|
||||
|
||||
state.enabled = export->suspend.enabled;
|
||||
ret = pwm_class_apply_state(export, pwm, &state);
|
||||
if (ret < 0)
|
||||
break;
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int pwm_class_suspend(struct device *pwmchip_dev)
|
||||
{
|
||||
struct pwm_chip *chip = pwmchip_from_dev(pwmchip_dev);
|
||||
unsigned int i;
|
||||
int ret = 0;
|
||||
|
||||
for (i = 0; i < chip->npwm; i++) {
|
||||
struct pwm_device *pwm = &chip->pwms[i];
|
||||
struct pwm_state state;
|
||||
struct pwm_export *export;
|
||||
|
||||
export = pwm_class_get_state(pwmchip_dev, pwm, &state);
|
||||
if (!export)
|
||||
continue;
|
||||
|
||||
/*
|
||||
* If pwmchip was not enabled before suspend, save
|
||||
* state for resume time and do nothing else.
|
||||
*/
|
||||
export->suspend = state;
|
||||
if (!state.enabled) {
|
||||
/* release lock taken in pwm_class_get_state */
|
||||
mutex_unlock(&export->lock);
|
||||
continue;
|
||||
}
|
||||
|
||||
state.enabled = false;
|
||||
ret = pwm_class_apply_state(export, pwm, &state);
|
||||
if (ret < 0) {
|
||||
/*
|
||||
* roll back the PWM devices that were disabled by
|
||||
* this suspend function.
|
||||
*/
|
||||
pwm_class_resume_npwm(pwmchip_dev, i);
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int pwm_class_resume(struct device *pwmchip_dev)
|
||||
{
|
||||
struct pwm_chip *chip = pwmchip_from_dev(pwmchip_dev);
|
||||
|
||||
return pwm_class_resume_npwm(pwmchip_dev, chip->npwm);
|
||||
}
|
||||
|
||||
static DEFINE_SIMPLE_DEV_PM_OPS(pwm_class_pm_ops, pwm_class_suspend, pwm_class_resume);
|
||||
|
||||
static struct class pwm_class = {
|
||||
.name = "pwm",
|
||||
.dev_groups = pwm_chip_groups,
|
||||
.pm = pm_sleep_ptr(&pwm_class_pm_ops),
|
||||
};
|
||||
|
||||
static int pwmchip_sysfs_match(struct device *pwmchip_dev, const void *data)
|
||||
{
|
||||
return pwmchip_from_dev(pwmchip_dev) == data;
|
||||
}
|
||||
|
||||
void pwmchip_sysfs_export(struct pwm_chip *chip)
|
||||
{
|
||||
struct device *pwmchip_dev;
|
||||
|
||||
/*
|
||||
* If device_create() fails the pwm_chip is still usable by
|
||||
* the kernel it's just not exported.
|
||||
*/
|
||||
pwmchip_dev = device_create(&pwm_class, pwmchip_parent(chip), MKDEV(0, 0), chip,
|
||||
"pwmchip%d", chip->id);
|
||||
if (IS_ERR(pwmchip_dev)) {
|
||||
dev_warn(pwmchip_parent(chip),
|
||||
"device_create failed for pwm_chip sysfs export\n");
|
||||
}
|
||||
}
|
||||
|
||||
void pwmchip_sysfs_unexport(struct pwm_chip *chip)
|
||||
{
|
||||
struct device *pwmchip_dev;
|
||||
unsigned int i;
|
||||
|
||||
pwmchip_dev = class_find_device(&pwm_class, NULL, chip,
|
||||
pwmchip_sysfs_match);
|
||||
if (!pwmchip_dev)
|
||||
return;
|
||||
|
||||
for (i = 0; i < chip->npwm; i++) {
|
||||
struct pwm_device *pwm = &chip->pwms[i];
|
||||
|
||||
if (test_bit(PWMF_EXPORTED, &pwm->flags))
|
||||
pwm_unexport_child(pwmchip_dev, pwm);
|
||||
}
|
||||
|
||||
put_device(pwmchip_dev);
|
||||
device_unregister(pwmchip_dev);
|
||||
}
|
||||
|
||||
static int __init pwm_sysfs_init(void)
|
||||
{
|
||||
return class_register(&pwm_class);
|
||||
}
|
||||
subsys_initcall(pwm_sysfs_init);
|
||||
@ -630,17 +630,4 @@ static inline void pwm_remove_table(struct pwm_lookup *table, size_t num)
|
||||
}
|
||||
#endif
|
||||
|
||||
#ifdef CONFIG_PWM_SYSFS
|
||||
void pwmchip_sysfs_export(struct pwm_chip *chip);
|
||||
void pwmchip_sysfs_unexport(struct pwm_chip *chip);
|
||||
#else
|
||||
static inline void pwmchip_sysfs_export(struct pwm_chip *chip)
|
||||
{
|
||||
}
|
||||
|
||||
static inline void pwmchip_sysfs_unexport(struct pwm_chip *chip)
|
||||
{
|
||||
}
|
||||
#endif /* CONFIG_PWM_SYSFS */
|
||||
|
||||
#endif /* __LINUX_PWM_H */
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user