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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/pwm/pwm-fsl-ftm.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/pwm/pwm-fsl-ftm.c')
-rw-r--r-- | drivers/pwm/pwm-fsl-ftm.c | 590 |
1 files changed, 590 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c new file mode 100644 index 000000000..883378d05 --- /dev/null +++ b/drivers/pwm/pwm-fsl-ftm.c @@ -0,0 +1,590 @@ +/* + * Freescale FlexTimer Module (FTM) PWM Driver + * + * Copyright 2012-2013 Freescale Semiconductor, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <linux/pwm.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +#define FTM_SC 0x00 +#define FTM_SC_CLK_MASK_SHIFT 3 +#define FTM_SC_CLK_MASK (3 << FTM_SC_CLK_MASK_SHIFT) +#define FTM_SC_CLK(c) (((c) + 1) << FTM_SC_CLK_MASK_SHIFT) +#define FTM_SC_PS_MASK 0x7 + +#define FTM_CNT 0x04 +#define FTM_MOD 0x08 + +#define FTM_CSC_BASE 0x0C +#define FTM_CSC_MSB BIT(5) +#define FTM_CSC_MSA BIT(4) +#define FTM_CSC_ELSB BIT(3) +#define FTM_CSC_ELSA BIT(2) +#define FTM_CSC(_channel) (FTM_CSC_BASE + ((_channel) * 8)) + +#define FTM_CV_BASE 0x10 +#define FTM_CV(_channel) (FTM_CV_BASE + ((_channel) * 8)) + +#define FTM_CNTIN 0x4C +#define FTM_STATUS 0x50 + +#define FTM_MODE 0x54 +#define FTM_MODE_FTMEN BIT(0) +#define FTM_MODE_INIT BIT(2) +#define FTM_MODE_PWMSYNC BIT(3) + +#define FTM_SYNC 0x58 +#define FTM_OUTINIT 0x5C +#define FTM_OUTMASK 0x60 +#define FTM_COMBINE 0x64 +#define FTM_DEADTIME 0x68 +#define FTM_EXTTRIG 0x6C +#define FTM_POL 0x70 +#define FTM_FMS 0x74 +#define FTM_FILTER 0x78 +#define FTM_FLTCTRL 0x7C +#define FTM_QDCTRL 0x80 +#define FTM_CONF 0x84 +#define FTM_FLTPOL 0x88 +#define FTM_SYNCONF 0x8C +#define FTM_INVCTRL 0x90 +#define FTM_SWOCTRL 0x94 +#define FTM_PWMLOAD 0x98 + +enum fsl_pwm_clk { + FSL_PWM_CLK_SYS, + FSL_PWM_CLK_FIX, + FSL_PWM_CLK_EXT, + FSL_PWM_CLK_CNTEN, + FSL_PWM_CLK_MAX +}; + +struct fsl_ftm_soc { + bool has_enable_bits; +}; + +struct fsl_pwm_chip { + struct pwm_chip chip; + + struct mutex lock; + + unsigned int cnt_select; + unsigned int clk_ps; + + struct regmap *regmap; + + int period_ns; + + struct clk *ipg_clk; + struct clk *clk[FSL_PWM_CLK_MAX]; + + const struct fsl_ftm_soc *soc; +}; + +static inline struct fsl_pwm_chip *to_fsl_chip(struct pwm_chip *chip) +{ + return container_of(chip, struct fsl_pwm_chip, chip); +} + +static int fsl_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) +{ + int ret; + struct fsl_pwm_chip *fpc = to_fsl_chip(chip); + + ret = clk_prepare_enable(fpc->ipg_clk); + if (!ret && fpc->soc->has_enable_bits) { + mutex_lock(&fpc->lock); + regmap_update_bits(fpc->regmap, FTM_SC, BIT(pwm->hwpwm + 16), + BIT(pwm->hwpwm + 16)); + mutex_unlock(&fpc->lock); + } + + return ret; +} + +static void fsl_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct fsl_pwm_chip *fpc = to_fsl_chip(chip); + + if (fpc->soc->has_enable_bits) { + mutex_lock(&fpc->lock); + regmap_update_bits(fpc->regmap, FTM_SC, BIT(pwm->hwpwm + 16), + 0); + mutex_unlock(&fpc->lock); + } + + clk_disable_unprepare(fpc->ipg_clk); +} + +static int fsl_pwm_calculate_default_ps(struct fsl_pwm_chip *fpc, + enum fsl_pwm_clk index) +{ + unsigned long sys_rate, cnt_rate; + unsigned long long ratio; + + sys_rate = clk_get_rate(fpc->clk[FSL_PWM_CLK_SYS]); + if (!sys_rate) + return -EINVAL; + + cnt_rate = clk_get_rate(fpc->clk[fpc->cnt_select]); + if (!cnt_rate) + return -EINVAL; + + switch (index) { + case FSL_PWM_CLK_SYS: + fpc->clk_ps = 1; + break; + case FSL_PWM_CLK_FIX: + ratio = 2 * cnt_rate - 1; + do_div(ratio, sys_rate); + fpc->clk_ps = ratio; + break; + case FSL_PWM_CLK_EXT: + ratio = 4 * cnt_rate - 1; + do_div(ratio, sys_rate); + fpc->clk_ps = ratio; + break; + default: + return -EINVAL; + } + + return 0; +} + +static unsigned long fsl_pwm_calculate_cycles(struct fsl_pwm_chip *fpc, + unsigned long period_ns) +{ + unsigned long long c, c0; + + c = clk_get_rate(fpc->clk[fpc->cnt_select]); + c = c * period_ns; + do_div(c, 1000000000UL); + + do { + c0 = c; + do_div(c0, (1 << fpc->clk_ps)); + if (c0 <= 0xFFFF) + return (unsigned long)c0; + } while (++fpc->clk_ps < 8); + + return 0; +} + +static unsigned long fsl_pwm_calculate_period_cycles(struct fsl_pwm_chip *fpc, + unsigned long period_ns, + enum fsl_pwm_clk index) +{ + int ret; + + ret = fsl_pwm_calculate_default_ps(fpc, index); + if (ret) { + dev_err(fpc->chip.dev, + "failed to calculate default prescaler: %d\n", + ret); + return 0; + } + + return fsl_pwm_calculate_cycles(fpc, period_ns); +} + +static unsigned long fsl_pwm_calculate_period(struct fsl_pwm_chip *fpc, + unsigned long period_ns) +{ + enum fsl_pwm_clk m0, m1; + unsigned long fix_rate, ext_rate, cycles; + + cycles = fsl_pwm_calculate_period_cycles(fpc, period_ns, + FSL_PWM_CLK_SYS); + if (cycles) { + fpc->cnt_select = FSL_PWM_CLK_SYS; + return cycles; + } + + fix_rate = clk_get_rate(fpc->clk[FSL_PWM_CLK_FIX]); + ext_rate = clk_get_rate(fpc->clk[FSL_PWM_CLK_EXT]); + + if (fix_rate > ext_rate) { + m0 = FSL_PWM_CLK_FIX; + m1 = FSL_PWM_CLK_EXT; + } else { + m0 = FSL_PWM_CLK_EXT; + m1 = FSL_PWM_CLK_FIX; + } + + cycles = fsl_pwm_calculate_period_cycles(fpc, period_ns, m0); + if (cycles) { + fpc->cnt_select = m0; + return cycles; + } + + fpc->cnt_select = m1; + + return fsl_pwm_calculate_period_cycles(fpc, period_ns, m1); +} + +static unsigned long fsl_pwm_calculate_duty(struct fsl_pwm_chip *fpc, + unsigned long period_ns, + unsigned long duty_ns) +{ + unsigned long long duty; + u32 val; + + regmap_read(fpc->regmap, FTM_MOD, &val); + duty = (unsigned long long)duty_ns * (val + 1); + do_div(duty, period_ns); + + return (unsigned long)duty; +} + +static int fsl_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, + int duty_ns, int period_ns) +{ + struct fsl_pwm_chip *fpc = to_fsl_chip(chip); + u32 period, duty; + + mutex_lock(&fpc->lock); + + /* + * The Freescale FTM controller supports only a single period for + * all PWM channels, therefore incompatible changes need to be + * refused. + */ + if (fpc->period_ns && fpc->period_ns != period_ns) { + dev_err(fpc->chip.dev, + "conflicting period requested for PWM %u\n", + pwm->hwpwm); + mutex_unlock(&fpc->lock); + return -EBUSY; + } + + if (!fpc->period_ns && duty_ns) { + period = fsl_pwm_calculate_period(fpc, period_ns); + if (!period) { + dev_err(fpc->chip.dev, "failed to calculate period\n"); + mutex_unlock(&fpc->lock); + return -EINVAL; + } + + regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_PS_MASK, + fpc->clk_ps); + regmap_write(fpc->regmap, FTM_MOD, period - 1); + + fpc->period_ns = period_ns; + } + + mutex_unlock(&fpc->lock); + + duty = fsl_pwm_calculate_duty(fpc, period_ns, duty_ns); + + regmap_write(fpc->regmap, FTM_CSC(pwm->hwpwm), + FTM_CSC_MSB | FTM_CSC_ELSB); + regmap_write(fpc->regmap, FTM_CV(pwm->hwpwm), duty); + + return 0; +} + +static int fsl_pwm_set_polarity(struct pwm_chip *chip, + struct pwm_device *pwm, + enum pwm_polarity polarity) +{ + struct fsl_pwm_chip *fpc = to_fsl_chip(chip); + u32 val; + + regmap_read(fpc->regmap, FTM_POL, &val); + + if (polarity == PWM_POLARITY_INVERSED) + val |= BIT(pwm->hwpwm); + else + val &= ~BIT(pwm->hwpwm); + + regmap_write(fpc->regmap, FTM_POL, val); + + return 0; +} + +static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc) +{ + int ret; + + /* select counter clock source */ + regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_CLK_MASK, + FTM_SC_CLK(fpc->cnt_select)); + + ret = clk_prepare_enable(fpc->clk[fpc->cnt_select]); + if (ret) + return ret; + + ret = clk_prepare_enable(fpc->clk[FSL_PWM_CLK_CNTEN]); + if (ret) { + clk_disable_unprepare(fpc->clk[fpc->cnt_select]); + return ret; + } + + return 0; +} + +static int fsl_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct fsl_pwm_chip *fpc = to_fsl_chip(chip); + int ret; + + mutex_lock(&fpc->lock); + regmap_update_bits(fpc->regmap, FTM_OUTMASK, BIT(pwm->hwpwm), 0); + + ret = fsl_counter_clock_enable(fpc); + mutex_unlock(&fpc->lock); + + return ret; +} + +static void fsl_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct fsl_pwm_chip *fpc = to_fsl_chip(chip); + u32 val; + + mutex_lock(&fpc->lock); + regmap_update_bits(fpc->regmap, FTM_OUTMASK, BIT(pwm->hwpwm), + BIT(pwm->hwpwm)); + + clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]); + clk_disable_unprepare(fpc->clk[fpc->cnt_select]); + + regmap_read(fpc->regmap, FTM_OUTMASK, &val); + if ((val & 0xFF) == 0xFF) + fpc->period_ns = 0; + + mutex_unlock(&fpc->lock); +} + +static const struct pwm_ops fsl_pwm_ops = { + .request = fsl_pwm_request, + .free = fsl_pwm_free, + .config = fsl_pwm_config, + .set_polarity = fsl_pwm_set_polarity, + .enable = fsl_pwm_enable, + .disable = fsl_pwm_disable, + .owner = THIS_MODULE, +}; + +static int fsl_pwm_init(struct fsl_pwm_chip *fpc) +{ + int ret; + + ret = clk_prepare_enable(fpc->ipg_clk); + if (ret) + return ret; + + regmap_write(fpc->regmap, FTM_CNTIN, 0x00); + regmap_write(fpc->regmap, FTM_OUTINIT, 0x00); + regmap_write(fpc->regmap, FTM_OUTMASK, 0xFF); + + clk_disable_unprepare(fpc->ipg_clk); + + return 0; +} + +static bool fsl_pwm_volatile_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case FTM_CNT: + return true; + } + return false; +} + +static const struct regmap_config fsl_pwm_regmap_config = { + .reg_bits = 32, + .reg_stride = 4, + .val_bits = 32, + + .max_register = FTM_PWMLOAD, + .volatile_reg = fsl_pwm_volatile_reg, + .cache_type = REGCACHE_FLAT, +}; + +static int fsl_pwm_probe(struct platform_device *pdev) +{ + struct fsl_pwm_chip *fpc; + struct resource *res; + void __iomem *base; + int ret; + + fpc = devm_kzalloc(&pdev->dev, sizeof(*fpc), GFP_KERNEL); + if (!fpc) + return -ENOMEM; + + mutex_init(&fpc->lock); + + fpc->soc = of_device_get_match_data(&pdev->dev); + fpc->chip.dev = &pdev->dev; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(base)) + return PTR_ERR(base); + + fpc->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "ftm_sys", base, + &fsl_pwm_regmap_config); + if (IS_ERR(fpc->regmap)) { + dev_err(&pdev->dev, "regmap init failed\n"); + return PTR_ERR(fpc->regmap); + } + + fpc->clk[FSL_PWM_CLK_SYS] = devm_clk_get(&pdev->dev, "ftm_sys"); + if (IS_ERR(fpc->clk[FSL_PWM_CLK_SYS])) { + dev_err(&pdev->dev, "failed to get \"ftm_sys\" clock\n"); + return PTR_ERR(fpc->clk[FSL_PWM_CLK_SYS]); + } + + fpc->clk[FSL_PWM_CLK_FIX] = devm_clk_get(fpc->chip.dev, "ftm_fix"); + if (IS_ERR(fpc->clk[FSL_PWM_CLK_FIX])) + return PTR_ERR(fpc->clk[FSL_PWM_CLK_FIX]); + + fpc->clk[FSL_PWM_CLK_EXT] = devm_clk_get(fpc->chip.dev, "ftm_ext"); + if (IS_ERR(fpc->clk[FSL_PWM_CLK_EXT])) + return PTR_ERR(fpc->clk[FSL_PWM_CLK_EXT]); + + fpc->clk[FSL_PWM_CLK_CNTEN] = + devm_clk_get(fpc->chip.dev, "ftm_cnt_clk_en"); + if (IS_ERR(fpc->clk[FSL_PWM_CLK_CNTEN])) + return PTR_ERR(fpc->clk[FSL_PWM_CLK_CNTEN]); + + /* + * ipg_clk is the interface clock for the IP. If not provided, use the + * ftm_sys clock as the default. + */ + fpc->ipg_clk = devm_clk_get(&pdev->dev, "ipg"); + if (IS_ERR(fpc->ipg_clk)) + fpc->ipg_clk = fpc->clk[FSL_PWM_CLK_SYS]; + + + fpc->chip.ops = &fsl_pwm_ops; + fpc->chip.of_xlate = of_pwm_xlate_with_flags; + fpc->chip.of_pwm_n_cells = 3; + fpc->chip.base = -1; + fpc->chip.npwm = 8; + + ret = pwmchip_add(&fpc->chip); + if (ret < 0) { + dev_err(&pdev->dev, "failed to add PWM chip: %d\n", ret); + return ret; + } + + platform_set_drvdata(pdev, fpc); + + return fsl_pwm_init(fpc); +} + +static int fsl_pwm_remove(struct platform_device *pdev) +{ + struct fsl_pwm_chip *fpc = platform_get_drvdata(pdev); + + return pwmchip_remove(&fpc->chip); +} + +#ifdef CONFIG_PM_SLEEP +static int fsl_pwm_suspend(struct device *dev) +{ + struct fsl_pwm_chip *fpc = dev_get_drvdata(dev); + int i; + + regcache_cache_only(fpc->regmap, true); + regcache_mark_dirty(fpc->regmap); + + for (i = 0; i < fpc->chip.npwm; i++) { + struct pwm_device *pwm = &fpc->chip.pwms[i]; + + if (!test_bit(PWMF_REQUESTED, &pwm->flags)) + continue; + + clk_disable_unprepare(fpc->ipg_clk); + + if (!pwm_is_enabled(pwm)) + continue; + + clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]); + clk_disable_unprepare(fpc->clk[fpc->cnt_select]); + } + + return 0; +} + +static int fsl_pwm_resume(struct device *dev) +{ + struct fsl_pwm_chip *fpc = dev_get_drvdata(dev); + int i; + + for (i = 0; i < fpc->chip.npwm; i++) { + struct pwm_device *pwm = &fpc->chip.pwms[i]; + + if (!test_bit(PWMF_REQUESTED, &pwm->flags)) + continue; + + clk_prepare_enable(fpc->ipg_clk); + + if (!pwm_is_enabled(pwm)) + continue; + + clk_prepare_enable(fpc->clk[fpc->cnt_select]); + clk_prepare_enable(fpc->clk[FSL_PWM_CLK_CNTEN]); + } + + /* restore all registers from cache */ + regcache_cache_only(fpc->regmap, false); + regcache_sync(fpc->regmap); + + return 0; +} +#endif + +static const struct dev_pm_ops fsl_pwm_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(fsl_pwm_suspend, fsl_pwm_resume) +}; + +static const struct fsl_ftm_soc vf610_ftm_pwm = { + .has_enable_bits = false, +}; + +static const struct fsl_ftm_soc imx8qm_ftm_pwm = { + .has_enable_bits = true, +}; + +static const struct of_device_id fsl_pwm_dt_ids[] = { + { .compatible = "fsl,vf610-ftm-pwm", .data = &vf610_ftm_pwm }, + { .compatible = "fsl,imx8qm-ftm-pwm", .data = &imx8qm_ftm_pwm }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, fsl_pwm_dt_ids); + +static struct platform_driver fsl_pwm_driver = { + .driver = { + .name = "fsl-ftm-pwm", + .of_match_table = fsl_pwm_dt_ids, + .pm = &fsl_pwm_pm_ops, + }, + .probe = fsl_pwm_probe, + .remove = fsl_pwm_remove, +}; +module_platform_driver(fsl_pwm_driver); + +MODULE_DESCRIPTION("Freescale FlexTimer Module PWM Driver"); +MODULE_AUTHOR("Xiubo Li <Li.Xiubo@freescale.com>"); +MODULE_ALIAS("platform:fsl-ftm-pwm"); +MODULE_LICENSE("GPL"); |