// SPDX-License-Identifier: GPL-2.0-or-later /* * Generic pwmlib implementation * * Copyright (C) 2011 Sascha Hauer <[email protected]> * Copyright (C) 2011-2012 Avionic Design GmbH */ #define DEFAULT_SYMBOL_NAMESPACE … #include <linux/acpi.h> #include <linux/module.h> #include <linux/idr.h> #include <linux/of.h> #include <linux/pwm.h> #include <linux/list.h> #include <linux/mutex.h> #include <linux/err.h> #include <linux/slab.h> #include <linux/device.h> #include <linux/debugfs.h> #include <linux/seq_file.h> #include <dt-bindings/pwm/pwm.h> #define CREATE_TRACE_POINTS #include <trace/events/pwm.h> /* protects access to pwm_chips */ static DEFINE_MUTEX(pwm_lock); static DEFINE_IDR(pwm_chips); static void pwm_apply_debug(struct pwm_device *pwm, const struct pwm_state *state) { … } static bool pwm_state_valid(const struct pwm_state *state) { … } /** * __pwm_apply() - atomically apply a new state to a PWM device * @pwm: PWM device * @state: new state to apply */ static int __pwm_apply(struct pwm_device *pwm, const struct pwm_state *state) { … } /** * pwm_apply_might_sleep() - atomically apply a new state to a PWM device * Cannot be used in atomic context. * @pwm: PWM device * @state: new state to apply */ int pwm_apply_might_sleep(struct pwm_device *pwm, const struct pwm_state *state) { … } EXPORT_SYMBOL_GPL(…); /** * pwm_apply_atomic() - apply a new state to a PWM device from atomic context * Not all PWM devices support this function, check with pwm_might_sleep(). * @pwm: PWM device * @state: new state to apply */ int pwm_apply_atomic(struct pwm_device *pwm, const struct pwm_state *state) { … } EXPORT_SYMBOL_GPL(…); /** * pwm_adjust_config() - adjust the current PWM config to the PWM arguments * @pwm: PWM device * * This function will adjust the PWM config to the PWM arguments provided * by the DT or PWM lookup table. This is particularly useful to adapt * the bootloader config to the Linux one. */ int pwm_adjust_config(struct pwm_device *pwm) { … } EXPORT_SYMBOL_GPL(…); /** * pwm_capture() - capture and report a PWM signal * @pwm: PWM device * @result: structure to fill with capture result * @timeout: time to wait, in milliseconds, before giving up on capture * * Returns: 0 on success or a negative error code on failure. */ int pwm_capture(struct pwm_device *pwm, struct pwm_capture *result, unsigned long timeout) { … } EXPORT_SYMBOL_GPL(…); static struct pwm_chip *pwmchip_find_by_name(const char *name) { … } static int pwm_device_request(struct pwm_device *pwm, const char *label) { … } /** * pwm_request_from_chip() - request a PWM device relative to a PWM chip * @chip: PWM chip * @index: per-chip index of the PWM to request * @label: a literal description string of this PWM * * Returns: A pointer to the PWM device at the given index of the given PWM * chip. A negative error code is returned if the index is not valid for the * specified PWM chip or if the PWM device cannot be requested. */ static struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, unsigned int index, const char *label) { … } struct pwm_device * of_pwm_xlate_with_flags(struct pwm_chip *chip, const struct of_phandle_args *args) { … } EXPORT_SYMBOL_GPL(…); struct pwm_device * of_pwm_single_xlate(struct pwm_chip *chip, const struct of_phandle_args *args) { … } EXPORT_SYMBOL_GPL(…); struct pwm_export { … }; static inline struct pwm_chip *pwmchip_from_dev(struct device *pwmchip_dev) { … } static inline struct pwm_export *pwmexport_from_dev(struct device *pwm_dev) { … } static inline struct pwm_device *pwm_from_dev(struct device *pwm_dev) { … } static ssize_t period_show(struct device *pwm_dev, struct device_attribute *attr, char *buf) { … } static ssize_t period_store(struct device *pwm_dev, struct device_attribute *attr, const char *buf, size_t size) { … } static ssize_t duty_cycle_show(struct device *pwm_dev, struct device_attribute *attr, char *buf) { … } static ssize_t duty_cycle_store(struct device *pwm_dev, struct device_attribute *attr, const char *buf, size_t size) { … } static ssize_t enable_show(struct device *pwm_dev, struct device_attribute *attr, char *buf) { … } static ssize_t enable_store(struct device *pwm_dev, struct device_attribute *attr, const char *buf, size_t size) { … } static ssize_t polarity_show(struct device *pwm_dev, struct device_attribute *attr, char *buf) { … } static ssize_t polarity_store(struct device *pwm_dev, struct device_attribute *attr, const char *buf, size_t size) { … } static ssize_t capture_show(struct device *pwm_dev, struct device_attribute *attr, char *buf) { … } 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[] = …; ATTRIBUTE_GROUPS(…); static void pwm_export_release(struct device *pwm_dev) { … } static int pwm_export_child(struct device *pwmchip_dev, struct pwm_device *pwm) { … } static int pwm_unexport_match(struct device *pwm_dev, void *data) { … } static int pwm_unexport_child(struct device *pwmchip_dev, struct pwm_device *pwm) { … } static ssize_t export_store(struct device *pwmchip_dev, struct device_attribute *attr, const char *buf, size_t 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) { … } static DEVICE_ATTR_WO(unexport); static ssize_t npwm_show(struct device *pwmchip_dev, struct device_attribute *attr, char *buf) { … } static DEVICE_ATTR_RO(npwm); static struct attribute *pwm_chip_attrs[] = …; ATTRIBUTE_GROUPS(…); /* 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) { … } static int pwm_class_apply_state(struct pwm_export *export, struct pwm_device *pwm, struct pwm_state *state) { … } static int pwm_class_resume_npwm(struct device *pwmchip_dev, unsigned int npwm) { … } static int pwm_class_suspend(struct device *pwmchip_dev) { … } static int pwm_class_resume(struct device *pwmchip_dev) { … } static DEFINE_SIMPLE_DEV_PM_OPS(pwm_class_pm_ops, pwm_class_suspend, pwm_class_resume); static struct class pwm_class = …; static void pwmchip_sysfs_unexport(struct pwm_chip *chip) { … } #define PWMCHIP_ALIGN … static void *pwmchip_priv(struct pwm_chip *chip) { … } /* This is the counterpart to pwmchip_alloc() */ void pwmchip_put(struct pwm_chip *chip) { … } EXPORT_SYMBOL_GPL(…); static void pwmchip_release(struct device *pwmchip_dev) { … } struct pwm_chip *pwmchip_alloc(struct device *parent, unsigned int npwm, size_t sizeof_priv) { … } EXPORT_SYMBOL_GPL(…); static void devm_pwmchip_put(void *data) { … } struct pwm_chip *devm_pwmchip_alloc(struct device *parent, unsigned int npwm, size_t sizeof_priv) { … } EXPORT_SYMBOL_GPL(…); static void of_pwmchip_add(struct pwm_chip *chip) { … } static void of_pwmchip_remove(struct pwm_chip *chip) { … } static bool pwm_ops_check(const struct pwm_chip *chip) { … } /** * __pwmchip_add() - register a new PWM chip * @chip: the PWM chip to add * @owner: reference to the module providing the chip. * * Register a new PWM chip. @owner is supposed to be THIS_MODULE, use the * pwmchip_add wrapper to do this right. * * Returns: 0 on success or a negative error code on failure. */ int __pwmchip_add(struct pwm_chip *chip, struct module *owner) { … } EXPORT_SYMBOL_GPL(…); /** * pwmchip_remove() - remove a PWM chip * @chip: the PWM chip to remove * * Removes a PWM chip. */ void pwmchip_remove(struct pwm_chip *chip) { … } EXPORT_SYMBOL_GPL(…); static void devm_pwmchip_remove(void *data) { … } int __devm_pwmchip_add(struct device *dev, struct pwm_chip *chip, struct module *owner) { … } EXPORT_SYMBOL_GPL(…); static struct device_link *pwm_device_link_add(struct device *dev, struct pwm_device *pwm) { … } static struct pwm_chip *fwnode_to_pwmchip(struct fwnode_handle *fwnode) { … } /** * of_pwm_get() - request a PWM via the PWM framework * @dev: device for PWM consumer * @np: device node to get the PWM from * @con_id: consumer name * * Returns the PWM device parsed from the phandle and index specified in the * "pwms" property of a device tree node or a negative error-code on failure. * Values parsed from the device tree are stored in the returned PWM device * object. * * If con_id is NULL, the first PWM device listed in the "pwms" property will * be requested. Otherwise the "pwm-names" property is used to do a reverse * lookup of the PWM index. This also means that the "pwm-names" property * becomes mandatory for devices that look up the PWM device via the con_id * parameter. * * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded * error code on failure. */ static struct pwm_device *of_pwm_get(struct device *dev, struct device_node *np, const char *con_id) { … } /** * acpi_pwm_get() - request a PWM via parsing "pwms" property in ACPI * @fwnode: firmware node to get the "pwms" property from * * Returns the PWM device parsed from the fwnode and index specified in the * "pwms" property or a negative error-code on failure. * Values parsed from the device tree are stored in the returned PWM device * object. * * This is analogous to of_pwm_get() except con_id is not yet supported. * ACPI entries must look like * Package () {"pwms", Package () * { <PWM device reference>, <PWM index>, <PWM period> [, <PWM flags>]}} * * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded * error code on failure. */ static struct pwm_device *acpi_pwm_get(const struct fwnode_handle *fwnode) { … } static DEFINE_MUTEX(pwm_lookup_lock); static LIST_HEAD(pwm_lookup_list); /** * pwm_add_table() - register PWM device consumers * @table: array of consumers to register * @num: number of consumers in table */ void pwm_add_table(struct pwm_lookup *table, size_t num) { … } /** * pwm_remove_table() - unregister PWM device consumers * @table: array of consumers to unregister * @num: number of consumers in table */ void pwm_remove_table(struct pwm_lookup *table, size_t num) { … } /** * pwm_get() - look up and request a PWM device * @dev: device for PWM consumer * @con_id: consumer name * * Lookup is first attempted using DT. If the device was not instantiated from * a device tree, a PWM chip and a relative index is looked up via a table * supplied by board setup code (see pwm_add_table()). * * Once a PWM chip has been found the specified PWM device will be requested * and is ready to be used. * * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded * error code on failure. */ struct pwm_device *pwm_get(struct device *dev, const char *con_id) { … } EXPORT_SYMBOL_GPL(…); /** * pwm_put() - release a PWM device * @pwm: PWM device */ void pwm_put(struct pwm_device *pwm) { … } EXPORT_SYMBOL_GPL(…); static void devm_pwm_release(void *pwm) { … } /** * devm_pwm_get() - resource managed pwm_get() * @dev: device for PWM consumer * @con_id: consumer name * * This function performs like pwm_get() but the acquired PWM device will * automatically be released on driver detach. * * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded * error code on failure. */ struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id) { … } EXPORT_SYMBOL_GPL(…); /** * devm_fwnode_pwm_get() - request a resource managed PWM from firmware node * @dev: device for PWM consumer * @fwnode: firmware node to get the PWM from * @con_id: consumer name * * Returns the PWM device parsed from the firmware node. See of_pwm_get() and * acpi_pwm_get() for a detailed description. * * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded * error code on failure. */ struct pwm_device *devm_fwnode_pwm_get(struct device *dev, struct fwnode_handle *fwnode, const char *con_id) { … } EXPORT_SYMBOL_GPL(…); static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s) { … } static void *pwm_seq_start(struct seq_file *s, loff_t *pos) { … } static void *pwm_seq_next(struct seq_file *s, void *v, loff_t *pos) { … } static void pwm_seq_stop(struct seq_file *s, void *v) { … } static int pwm_seq_show(struct seq_file *s, void *v) { … } static const struct seq_operations pwm_debugfs_sops = …; DEFINE_SEQ_ATTRIBUTE(…); static int __init pwm_init(void) { … } subsys_initcall(pwm_init);
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