// SPDX-License-Identifier: GPL-2.0-only /* * NXP LPC18xx State Configurable Timer - Pulse Width Modulator driver * * Copyright (c) 2015 Ariel D'Alessandro <[email protected]> * * Notes * ===== * NXP LPC18xx provides a State Configurable Timer (SCT) which can be configured * as a Pulse Width Modulator. * * SCT supports 16 outputs, 16 events and 16 registers. Each event will be * triggered when its related register matches the SCT counter value, and it * will set or clear a selected output. * * One of the events is preselected to generate the period, thus the maximum * number of simultaneous channels is limited to 15. Notice that period is * global to all the channels, thus PWM driver will refuse setting different * values to it, unless there's only one channel requested. */ #include <linux/clk.h> #include <linux/err.h> #include <linux/io.h> #include <linux/mod_devicetable.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/pwm.h> /* LPC18xx SCT registers */ #define LPC18XX_PWM_CONFIG … #define LPC18XX_PWM_CONFIG_UNIFY … #define LPC18XX_PWM_CONFIG_NORELOAD … #define LPC18XX_PWM_CTRL … #define LPC18XX_PWM_CTRL_HALT … #define LPC18XX_PWM_BIDIR … #define LPC18XX_PWM_PRE_SHIFT … #define LPC18XX_PWM_PRE_MASK … #define LPC18XX_PWM_PRE(x) … #define LPC18XX_PWM_LIMIT … #define LPC18XX_PWM_RES_BASE … #define LPC18XX_PWM_RES_SHIFT(_ch) … #define LPC18XX_PWM_RES(_ch, _action) … #define LPC18XX_PWM_RES_MASK(_ch) … #define LPC18XX_PWM_MATCH_BASE … #define LPC18XX_PWM_MATCH(_ch) … #define LPC18XX_PWM_MATCHREL_BASE … #define LPC18XX_PWM_MATCHREL(_ch) … #define LPC18XX_PWM_EVSTATEMSK_BASE … #define LPC18XX_PWM_EVSTATEMSK(_ch) … #define LPC18XX_PWM_EVSTATEMSK_ALL … #define LPC18XX_PWM_EVCTRL_BASE … #define LPC18XX_PWM_EVCTRL(_ev) … #define LPC18XX_PWM_EVCTRL_MATCH(_ch) … #define LPC18XX_PWM_EVCTRL_COMB_SHIFT … #define LPC18XX_PWM_EVCTRL_COMB_MATCH … #define LPC18XX_PWM_OUTPUTSET_BASE … #define LPC18XX_PWM_OUTPUTSET(_ch) … #define LPC18XX_PWM_OUTPUTCL_BASE … #define LPC18XX_PWM_OUTPUTCL(_ch) … /* LPC18xx SCT unified counter */ #define LPC18XX_PWM_TIMER_MAX … /* LPC18xx SCT events */ #define LPC18XX_PWM_EVENT_PERIOD … #define LPC18XX_PWM_EVENT_MAX … #define LPC18XX_NUM_PWMS … /* SCT conflict resolution */ enum lpc18xx_pwm_res_action { … }; struct lpc18xx_pwm_data { … }; struct lpc18xx_pwm_chip { … }; static inline struct lpc18xx_pwm_chip * to_lpc18xx_pwm_chip(struct pwm_chip *chip) { … } static inline void lpc18xx_pwm_writel(struct lpc18xx_pwm_chip *lpc18xx_pwm, u32 reg, u32 val) { … } static inline u32 lpc18xx_pwm_readl(struct lpc18xx_pwm_chip *lpc18xx_pwm, u32 reg) { … } static void lpc18xx_pwm_set_conflict_res(struct lpc18xx_pwm_chip *lpc18xx_pwm, struct pwm_device *pwm, enum lpc18xx_pwm_res_action action) { … } static void lpc18xx_pwm_config_period(struct pwm_chip *chip, u64 period_ns) { … } static void lpc18xx_pwm_config_duty(struct pwm_chip *chip, struct pwm_device *pwm, u64 duty_ns) { … } static int lpc18xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns) { … } static int lpc18xx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm, enum pwm_polarity polarity) { … } static void lpc18xx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) { … } static int lpc18xx_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) { … } static void lpc18xx_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) { … } static int lpc18xx_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, const struct pwm_state *state) { … } static const struct pwm_ops lpc18xx_pwm_ops = …; static const struct of_device_id lpc18xx_pwm_of_match[] = …; MODULE_DEVICE_TABLE(of, lpc18xx_pwm_of_match); static int lpc18xx_pwm_probe(struct platform_device *pdev) { … } static void lpc18xx_pwm_remove(struct platform_device *pdev) { … } static struct platform_driver lpc18xx_pwm_driver = …; module_platform_driver(…) …; MODULE_AUTHOR(…) …; MODULE_DESCRIPTION(…) …; MODULE_LICENSE(…) …;
Codebase Browser
linux