/* * Marvell Berlin PWM driver * * Copyright (C) 2015 Marvell Technology Group Ltd. * * Author: Antoine Tenart <[email protected]> * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. */ #include <linux/clk.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/mod_devicetable.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/pwm.h> #include <linux/slab.h> #define BERLIN_PWM_EN … #define BERLIN_PWM_ENABLE … #define BERLIN_PWM_CONTROL … /* * The prescaler claims to support 8 different moduli, configured using the * low three bits of PWM_CONTROL. (Sequentially, they are 1, 4, 8, 16, 64, * 256, 1024, and 4096.) However, the moduli from 4 to 1024 appear to be * implemented by internally shifting TCNT left without adding additional * bits. So, the max TCNT that actually works for a modulus of 4 is 0x3fff; * for 8, 0x1fff; and so on. This means that those moduli are entirely * useless, as we could just do the shift ourselves. The 4096 modulus is * implemented with a real prescaler, so we do use that, but we treat it * as a flag instead of pretending the modulus is actually configurable. */ #define BERLIN_PWM_PRESCALE_4096 … #define BERLIN_PWM_INVERT_POLARITY … #define BERLIN_PWM_DUTY … #define BERLIN_PWM_TCNT … #define BERLIN_PWM_MAX_TCNT … #define BERLIN_PWM_NUMPWMS … struct berlin_pwm_channel { … }; struct berlin_pwm_chip { … }; static inline struct berlin_pwm_chip *to_berlin_pwm_chip(struct pwm_chip *chip) { … } static inline u32 berlin_pwm_readl(struct berlin_pwm_chip *bpc, unsigned int channel, unsigned long offset) { … } static inline void berlin_pwm_writel(struct berlin_pwm_chip *bpc, unsigned int channel, u32 value, unsigned long offset) { … } static int berlin_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, u64 duty_ns, u64 period_ns) { … } static int berlin_pwm_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm, enum pwm_polarity polarity) { … } static int berlin_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) { … } static void berlin_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) { … } static int berlin_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, const struct pwm_state *state) { … } static const struct pwm_ops berlin_pwm_ops = …; static const struct of_device_id berlin_pwm_match[] = …; MODULE_DEVICE_TABLE(of, berlin_pwm_match); static int berlin_pwm_probe(struct platform_device *pdev) { … } static int berlin_pwm_suspend(struct device *dev) { … } static int berlin_pwm_resume(struct device *dev) { … } static DEFINE_SIMPLE_DEV_PM_OPS(berlin_pwm_pm_ops, berlin_pwm_suspend, berlin_pwm_resume); static struct platform_driver berlin_pwm_driver = …; module_platform_driver(…) …; MODULE_AUTHOR(…) …; MODULE_DESCRIPTION(…) …; MODULE_LICENSE(…) …;
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