// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause /* * PWM controller driver for Amlogic Meson SoCs. * * This PWM is only a set of Gates, Dividers and Counters: * PWM output is achieved by calculating a clock that permits calculating * two periods (low and high). The counter then has to be set to switch after * N cycles for the first half period. * The hardware has no "polarity" setting. This driver reverses the period * cycles (the low length is inverted with the high length) for * PWM_POLARITY_INVERSED. This means that .get_state cannot read the polarity * from the hardware. * Setting the duty cycle will disable and re-enable the PWM output. * Disabling the PWM stops the output immediately (without waiting for the * current period to complete first). * * The public S912 (GXM) datasheet contains some documentation for this PWM * controller starting on page 543: * https://dl.khadas.com/Hardware/VIM2/Datasheet/S912_Datasheet_V0.220170314publicversion-Wesion.pdf * An updated version of this IP block is found in S922X (G12B) SoCs. The * datasheet contains the description for this IP block revision starting at * page 1084: * https://dn.odroid.com/S922X/ODROID-N2/Datasheet/S922X_Public_Datasheet_V0.2.pdf * * Copyright (c) 2016 BayLibre, SAS. * Author: Neil Armstrong <[email protected]> * Copyright (C) 2014 Amlogic, Inc. */ #include <linux/bitfield.h> #include <linux/bits.h> #include <linux/clk.h> #include <linux/clk-provider.h> #include <linux/err.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/math64.h> #include <linux/module.h> #include <linux/of.h> #include <linux/platform_device.h> #include <linux/pwm.h> #include <linux/slab.h> #include <linux/spinlock.h> #define REG_PWM_A … #define REG_PWM_B … #define PWM_LOW_MASK … #define PWM_HIGH_MASK … #define REG_MISC_AB … #define MISC_B_CLK_EN_SHIFT … #define MISC_A_CLK_EN_SHIFT … #define MISC_CLK_DIV_WIDTH … #define MISC_B_CLK_DIV_SHIFT … #define MISC_A_CLK_DIV_SHIFT … #define MISC_B_CLK_SEL_SHIFT … #define MISC_A_CLK_SEL_SHIFT … #define MISC_CLK_SEL_MASK … #define MISC_B_EN … #define MISC_A_EN … #define MESON_NUM_PWMS … #define MESON_NUM_MUX_PARENTS … static struct meson_pwm_channel_data { … } meson_pwm_per_channel_data[MESON_NUM_PWMS] = …; struct meson_pwm_channel { … }; struct meson_pwm_data { … }; struct meson_pwm { … }; static inline struct meson_pwm *to_meson_pwm(struct pwm_chip *chip) { … } static int meson_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) { … } static void meson_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) { … } static int meson_pwm_calc(struct pwm_chip *chip, struct pwm_device *pwm, const struct pwm_state *state) { … } static void meson_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) { … } static void meson_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) { … } static int meson_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, const struct pwm_state *state) { … } static u64 meson_pwm_cnt_to_ns(struct pwm_chip *chip, struct pwm_device *pwm, u32 cnt) { … } static int meson_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, struct pwm_state *state) { … } static const struct pwm_ops meson_pwm_ops = …; static int meson_pwm_init_clocks_meson8b(struct pwm_chip *chip, struct clk_parent_data *mux_parent_data) { … } static int meson_pwm_init_channels_meson8b_legacy(struct pwm_chip *chip) { … } static int meson_pwm_init_channels_meson8b_v2(struct pwm_chip *chip) { … } static void meson_pwm_s4_put_clk(void *data) { … } static int meson_pwm_init_channels_s4(struct pwm_chip *chip) { … } static const struct meson_pwm_data pwm_meson8b_data = …; /* * Only the 2 first inputs of the GXBB AO PWMs are valid * The last 2 are grounded */ static const struct meson_pwm_data pwm_gxbb_ao_data = …; static const struct meson_pwm_data pwm_axg_ee_data = …; static const struct meson_pwm_data pwm_axg_ao_data = …; static const struct meson_pwm_data pwm_g12a_ao_ab_data = …; static const struct meson_pwm_data pwm_g12a_ao_cd_data = …; static const struct meson_pwm_data pwm_meson8_v2_data = …; static const struct meson_pwm_data pwm_s4_data = …; static const struct of_device_id meson_pwm_matches[] = …; MODULE_DEVICE_TABLE(of, meson_pwm_matches); static int meson_pwm_probe(struct platform_device *pdev) { … } static struct platform_driver meson_pwm_driver = …; module_platform_driver(…) …; MODULE_DESCRIPTION(…) …; MODULE_AUTHOR(…) …; MODULE_LICENSE(…) …;
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