[mirror_ubuntu-zesty-kernel.git] / drivers / pwm / pwm-fsl-ftm.c

/*
 *  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/platform_device.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_pwm_chip {
	struct pwm_chip chip;

	struct mutex lock;

	unsigned int use_count;
	unsigned int cnt_select;
	unsigned int clk_ps;

	struct regmap *regmap;

	int period_ns;

	struct clk *clk[FSL_PWM_CLK_MAX];
};

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)
{
	struct fsl_pwm_chip *fpc = to_fsl_chip(chip);

	return clk_prepare_enable(fpc->clk[FSL_PWM_CLK_SYS]);
}

static void fsl_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
{
	struct fsl_pwm_chip *fpc = to_fsl_chip(chip);

	clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_SYS]);
}

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;

	if (fpc->use_count++ != 0)
		return 0;

	/* 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_counter_clock_disable(struct fsl_pwm_chip *fpc)
{
	/*
	 * already disabled, do nothing
	 */
	if (fpc->use_count == 0)
		return;

	/* there are still users, so can't disable yet */
	if (--fpc->use_count > 0)
		return;

	/* no users left, disable PWM counter clock */
	regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_CLK_MASK, 0);

	clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]);
	clk_disable_unprepare(fpc->clk[fpc->cnt_select]);
}

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));

	fsl_counter_clock_disable(fpc);

	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->clk[FSL_PWM_CLK_SYS]);
	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->clk[FSL_PWM_CLK_SYS]);

	return 0;
}

static const struct regmap_config fsl_pwm_regmap_config = {
	.reg_bits = 32,
	.reg_stride = 4,
	.val_bits = 32,

	.max_register = FTM_PWMLOAD,
};

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->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, NULL, 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]);

	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;
	fpc->chip.can_sleep = true;

	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);
}

static const struct of_device_id fsl_pwm_dt_ids[] = {
	{ .compatible = "fsl,vf610-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,
	},
	.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");
Commit	Line	Data
b505183b XL	1	/*
	2	* Freescale FlexTimer Module (FTM) PWM Driver
	3	*
	4	* Copyright 2012-2013 Freescale Semiconductor, Inc.
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*/
	11
	12	#include <linux/clk.h>
	13	#include <linux/err.h>
	14	#include <linux/io.h>
	15	#include <linux/kernel.h>
	16	#include <linux/module.h>
	17	#include <linux/mutex.h>
	18	#include <linux/of_address.h>
	19	#include <linux/platform_device.h>
	20	#include <linux/pwm.h>
42fa98a9	21	#include <linux/regmap.h>
b505183b XL	22	#include <linux/slab.h>
	23
	24	#define FTM_SC 0x00
cd6d92d2 XL	25	#define FTM_SC_CLK_MASK_SHIFT 3
	26	#define FTM_SC_CLK_MASK (3 << FTM_SC_CLK_MASK_SHIFT)
	27	#define FTM_SC_CLK(c) (((c) + 1) << FTM_SC_CLK_MASK_SHIFT)
b505183b	28	#define FTM_SC_PS_MASK 0x7
b505183b XL	29
	30	#define FTM_CNT 0x04
	31	#define FTM_MOD 0x08
	32
	33	#define FTM_CSC_BASE 0x0C
	34	#define FTM_CSC_MSB BIT(5)
	35	#define FTM_CSC_MSA BIT(4)
	36	#define FTM_CSC_ELSB BIT(3)
	37	#define FTM_CSC_ELSA BIT(2)
	38	#define FTM_CSC(_channel) (FTM_CSC_BASE + ((_channel) * 8))
	39
	40	#define FTM_CV_BASE 0x10
	41	#define FTM_CV(_channel) (FTM_CV_BASE + ((_channel) * 8))
	42
	43	#define FTM_CNTIN 0x4C
	44	#define FTM_STATUS 0x50
	45
	46	#define FTM_MODE 0x54
	47	#define FTM_MODE_FTMEN BIT(0)
	48	#define FTM_MODE_INIT BIT(2)
	49	#define FTM_MODE_PWMSYNC BIT(3)
	50
	51	#define FTM_SYNC 0x58
	52	#define FTM_OUTINIT 0x5C
	53	#define FTM_OUTMASK 0x60
	54	#define FTM_COMBINE 0x64
	55	#define FTM_DEADTIME 0x68
	56	#define FTM_EXTTRIG 0x6C
	57	#define FTM_POL 0x70
	58	#define FTM_FMS 0x74
	59	#define FTM_FILTER 0x78
	60	#define FTM_FLTCTRL 0x7C
	61	#define FTM_QDCTRL 0x80
	62	#define FTM_CONF 0x84
	63	#define FTM_FLTPOL 0x88
	64	#define FTM_SYNCONF 0x8C
	65	#define FTM_INVCTRL 0x90
	66	#define FTM_SWOCTRL 0x94
	67	#define FTM_PWMLOAD 0x98
	68
	69	enum fsl_pwm_clk {
	70	FSL_PWM_CLK_SYS,
	71	FSL_PWM_CLK_FIX,
	72	FSL_PWM_CLK_EXT,
	73	FSL_PWM_CLK_CNTEN,
	74	FSL_PWM_CLK_MAX
	75	};
	76
	77	struct fsl_pwm_chip {
	78	struct pwm_chip chip;
	79
	80	struct mutex lock;
	81
	82	unsigned int use_count;
	83	unsigned int cnt_select;
	84	unsigned int clk_ps;
	85
42fa98a9	86	struct regmap *regmap;
b505183b XL	87
	88	int period_ns;
	89
	90	struct clk *clk[FSL_PWM_CLK_MAX];
	91	};
	92
	93	static inline struct fsl_pwm_chip to_fsl_chip(struct pwm_chip chip)
	94	{
	95	return container_of(chip, struct fsl_pwm_chip, chip);
	96	}
	97
	98	static int fsl_pwm_request(struct pwm_chip chip, struct pwm_device pwm)
	99	{
	100	struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
	101
	102	return clk_prepare_enable(fpc->clk[FSL_PWM_CLK_SYS]);
	103	}
	104
	105	static void fsl_pwm_free(struct pwm_chip chip, struct pwm_device pwm)
	106	{
	107	struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
	108
	109	clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_SYS]);
	110	}
	111
	112	static int fsl_pwm_calculate_default_ps(struct fsl_pwm_chip *fpc,
	113	enum fsl_pwm_clk index)
	114	{
	115	unsigned long sys_rate, cnt_rate;
	116	unsigned long long ratio;
	117
	118	sys_rate = clk_get_rate(fpc->clk[FSL_PWM_CLK_SYS]);
	119	if (!sys_rate)
	120	return -EINVAL;
	121
	122	cnt_rate = clk_get_rate(fpc->clk[fpc->cnt_select]);
	123	if (!cnt_rate)
	124	return -EINVAL;
	125
	126	switch (index) {
	127	case FSL_PWM_CLK_SYS:
	128	fpc->clk_ps = 1;
	129	break;
	130	case FSL_PWM_CLK_FIX:
	131	ratio = 2 * cnt_rate - 1;
	132	do_div(ratio, sys_rate);
	133	fpc->clk_ps = ratio;
	134	break;
	135	case FSL_PWM_CLK_EXT:
	136	ratio = 4 * cnt_rate - 1;
	137	do_div(ratio, sys_rate);
	138	fpc->clk_ps = ratio;
	139	break;
	140	default:
	141	return -EINVAL;
	142	}
	143
	144	return 0;
	145	}
	146
	147	static unsigned long fsl_pwm_calculate_cycles(struct fsl_pwm_chip *fpc,
	148	unsigned long period_ns)
	149	{
	150	unsigned long long c, c0;
151
152	c = clk_get_rate(fpc->clk[fpc->cnt_select]);
153	c = c * period_ns;
154	do_div(c, 1000000000UL);
155
156	do {
157	c0 = c;
158	do_div(c0, (1 << fpc->clk_ps));
159	if (c0 <= 0xFFFF)
160	return (unsigned long)c0;
161	} while (++fpc->clk_ps < 8);
162
163	return 0;
164	}
165
166	static unsigned long fsl_pwm_calculate_period_cycles(struct fsl_pwm_chip *fpc,
167	unsigned long period_ns,
168	enum fsl_pwm_clk index)
169	{
170	int ret;
171
172	ret = fsl_pwm_calculate_default_ps(fpc, index);
173	if (ret) {
174	dev_err(fpc->chip.dev,
175	"failed to calculate default prescaler: %d\n",
176	ret);
177	return 0;
178	}
179
180	return fsl_pwm_calculate_cycles(fpc, period_ns);
181	}
182
183	static unsigned long fsl_pwm_calculate_period(struct fsl_pwm_chip *fpc,
184	unsigned long period_ns)
185	{
186	enum fsl_pwm_clk m0, m1;
187	unsigned long fix_rate, ext_rate, cycles;
188
189	cycles = fsl_pwm_calculate_period_cycles(fpc, period_ns,
190	FSL_PWM_CLK_SYS);
191	if (cycles) {
192	fpc->cnt_select = FSL_PWM_CLK_SYS;
193	return cycles;
194	}
195
196	fix_rate = clk_get_rate(fpc->clk[FSL_PWM_CLK_FIX]);
197	ext_rate = clk_get_rate(fpc->clk[FSL_PWM_CLK_EXT]);
198
199	if (fix_rate > ext_rate) {
200	m0 = FSL_PWM_CLK_FIX;
201	m1 = FSL_PWM_CLK_EXT;
202	} else {
203	m0 = FSL_PWM_CLK_EXT;
204	m1 = FSL_PWM_CLK_FIX;
205	}
206
207	cycles = fsl_pwm_calculate_period_cycles(fpc, period_ns, m0);
208	if (cycles) {
209	fpc->cnt_select = m0;
210	return cycles;
211	}
212
213	fpc->cnt_select = m1;
214
215	return fsl_pwm_calculate_period_cycles(fpc, period_ns, m1);
216	}
217
218	static unsigned long fsl_pwm_calculate_duty(struct fsl_pwm_chip *fpc,
219	unsigned long period_ns,
220	unsigned long duty_ns)
221	{
42fa98a9 XL	222	unsigned long long duty;
42fa98a9 XL	223	u32 val;
b505183b	224
42fa98a9 XL	225	regmap_read(fpc->regmap, FTM_MOD, &val);
42fa98a9 XL	226	duty = (unsigned long long)duty_ns * (val + 1);
b505183b XL	227	do_div(duty, period_ns);
	228
	229	return (unsigned long)duty;
	230	}
	231
	232	static int fsl_pwm_config(struct pwm_chip chip, struct pwm_device pwm,
	233	int duty_ns, int period_ns)
	234	{
	235	struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
42fa98a9	236	u32 period, duty;
b505183b XL	237
	238	mutex_lock(&fpc->lock);
	239
	240	/*
	241	* The Freescale FTM controller supports only a single period for
	242	* all PWM channels, therefore incompatible changes need to be
	243	* refused.
	244	*/
	245	if (fpc->period_ns && fpc->period_ns != period_ns) {
	246	dev_err(fpc->chip.dev,
	247	"conflicting period requested for PWM %u\n",
	248	pwm->hwpwm);
	249	mutex_unlock(&fpc->lock);
	250	return -EBUSY;
	251	}
	252
	253	if (!fpc->period_ns && duty_ns) {
	254	period = fsl_pwm_calculate_period(fpc, period_ns);
	255	if (!period) {
	256	dev_err(fpc->chip.dev, "failed to calculate period\n");
	257	mutex_unlock(&fpc->lock);
	258	return -EINVAL;
	259	}
	260
42fa98a9 XL	261	regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_PS_MASK,
	262	fpc->clk_ps);
	263	regmap_write(fpc->regmap, FTM_MOD, period - 1);
b505183b XL	264
	265	fpc->period_ns = period_ns;
	266	}
	267
	268	mutex_unlock(&fpc->lock);
	269
	270	duty = fsl_pwm_calculate_duty(fpc, period_ns, duty_ns);
	271
42fa98a9 XL	272	regmap_write(fpc->regmap, FTM_CSC(pwm->hwpwm),
	273	FTM_CSC_MSB \| FTM_CSC_ELSB);
	274	regmap_write(fpc->regmap, FTM_CV(pwm->hwpwm), duty);
b505183b XL	275
	276	return 0;
	277	}
	278
	279	static int fsl_pwm_set_polarity(struct pwm_chip *chip,
	280	struct pwm_device *pwm,
	281	enum pwm_polarity polarity)
	282	{
	283	struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
	284	u32 val;
	285
42fa98a9	286	regmap_read(fpc->regmap, FTM_POL, &val);
b505183b XL	287
	288	if (polarity == PWM_POLARITY_INVERSED)
	289	val \|= BIT(pwm->hwpwm);
	290	else
	291	val &= ~BIT(pwm->hwpwm);
	292
42fa98a9	293	regmap_write(fpc->regmap, FTM_POL, val);
b505183b XL	294
	295	return 0;
	296	}
	297
	298	static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc)
	299	{
b505183b XL	300	int ret;
b505183b XL	301
8e6e7651	302	if (fpc->use_count++ != 0)
b505183b XL	303	return 0;
	304
	305	/* select counter clock source */
42fa98a9 XL	306	regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_CLK_MASK,
42fa98a9 XL	307	FTM_SC_CLK(fpc->cnt_select));
b505183b XL	308
	309	ret = clk_prepare_enable(fpc->clk[fpc->cnt_select]);
	310	if (ret)
	311	return ret;
	312
	313	ret = clk_prepare_enable(fpc->clk[FSL_PWM_CLK_CNTEN]);
	314	if (ret) {
	315	clk_disable_unprepare(fpc->clk[fpc->cnt_select]);
	316	return ret;
	317	}
	318
b505183b XL	319	return 0;
	320	}
	321
	322	static int fsl_pwm_enable(struct pwm_chip chip, struct pwm_device pwm)
	323	{
	324	struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
b505183b XL	325	int ret;
	326
	327	mutex_lock(&fpc->lock);
42fa98a9	328	regmap_update_bits(fpc->regmap, FTM_OUTMASK, BIT(pwm->hwpwm), 0);
b505183b XL	329
	330	ret = fsl_counter_clock_enable(fpc);
	331	mutex_unlock(&fpc->lock);
	332
	333	return ret;
	334	}
	335
	336	static void fsl_counter_clock_disable(struct fsl_pwm_chip *fpc)
	337	{
b505183b XL	338	/*
	339	* already disabled, do nothing
	340	*/
	341	if (fpc->use_count == 0)
	342	return;
	343
	344	/* there are still users, so can't disable yet */
	345	if (--fpc->use_count > 0)
	346	return;
	347
	348	/* no users left, disable PWM counter clock */
42fa98a9	349	regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_CLK_MASK, 0);
b505183b XL	350
	351	clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]);
	352	clk_disable_unprepare(fpc->clk[fpc->cnt_select]);
	353	}
	354
	355	static void fsl_pwm_disable(struct pwm_chip chip, struct pwm_device pwm)
	356	{
	357	struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
	358	u32 val;
	359
	360	mutex_lock(&fpc->lock);
42fa98a9 XL	361	regmap_update_bits(fpc->regmap, FTM_OUTMASK, BIT(pwm->hwpwm),
42fa98a9 XL	362	BIT(pwm->hwpwm));
b505183b XL	363
	364	fsl_counter_clock_disable(fpc);
	365
42fa98a9	366	regmap_read(fpc->regmap, FTM_OUTMASK, &val);
b505183b XL	367	if ((val & 0xFF) == 0xFF)
	368	fpc->period_ns = 0;
	369
	370	mutex_unlock(&fpc->lock);
	371	}
	372
	373	static const struct pwm_ops fsl_pwm_ops = {
	374	.request = fsl_pwm_request,
	375	.free = fsl_pwm_free,
	376	.config = fsl_pwm_config,
	377	.set_polarity = fsl_pwm_set_polarity,
	378	.enable = fsl_pwm_enable,
	379	.disable = fsl_pwm_disable,
	380	.owner = THIS_MODULE,
	381	};
	382
	383	static int fsl_pwm_init(struct fsl_pwm_chip *fpc)
	384	{
	385	int ret;
	386
	387	ret = clk_prepare_enable(fpc->clk[FSL_PWM_CLK_SYS]);
	388	if (ret)
	389	return ret;
	390
42fa98a9 XL	391	regmap_write(fpc->regmap, FTM_CNTIN, 0x00);
	392	regmap_write(fpc->regmap, FTM_OUTINIT, 0x00);
	393	regmap_write(fpc->regmap, FTM_OUTMASK, 0xFF);
b505183b XL	394
	395	clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_SYS]);
	396
	397	return 0;
	398	}
	399
42fa98a9 XL	400	static const struct regmap_config fsl_pwm_regmap_config = {
	401	.reg_bits = 32,
	402	.reg_stride = 4,
	403	.val_bits = 32,
	404
	405	.max_register = FTM_PWMLOAD,
	406	};
	407
b505183b XL	408	static int fsl_pwm_probe(struct platform_device *pdev)
	409	{
	410	struct fsl_pwm_chip *fpc;
	411	struct resource *res;
42fa98a9	412	void __iomem *base;
b505183b XL	413	int ret;
	414
	415	fpc = devm_kzalloc(&pdev->dev, sizeof(*fpc), GFP_KERNEL);
	416	if (!fpc)
	417	return -ENOMEM;
	418
	419	mutex_init(&fpc->lock);
	420
	421	fpc->chip.dev = &pdev->dev;
	422
	423	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
42fa98a9 XL	424	base = devm_ioremap_resource(&pdev->dev, res);
	425	if (IS_ERR(base))
	426	return PTR_ERR(base);
	427
	428	fpc->regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base,
	429	&fsl_pwm_regmap_config);
	430	if (IS_ERR(fpc->regmap)) {
	431	dev_err(&pdev->dev, "regmap init failed\n");
	432	return PTR_ERR(fpc->regmap);
	433	}
b505183b XL	434
	435	fpc->clk[FSL_PWM_CLK_SYS] = devm_clk_get(&pdev->dev, "ftm_sys");
	436	if (IS_ERR(fpc->clk[FSL_PWM_CLK_SYS])) {
	437	dev_err(&pdev->dev, "failed to get \"ftm_sys\" clock\n");
	438	return PTR_ERR(fpc->clk[FSL_PWM_CLK_SYS]);
	439	}
	440
	441	fpc->clk[FSL_PWM_CLK_FIX] = devm_clk_get(fpc->chip.dev, "ftm_fix");
	442	if (IS_ERR(fpc->clk[FSL_PWM_CLK_FIX]))
	443	return PTR_ERR(fpc->clk[FSL_PWM_CLK_FIX]);
	444
	445	fpc->clk[FSL_PWM_CLK_EXT] = devm_clk_get(fpc->chip.dev, "ftm_ext");
	446	if (IS_ERR(fpc->clk[FSL_PWM_CLK_EXT]))
	447	return PTR_ERR(fpc->clk[FSL_PWM_CLK_EXT]);
	448
	449	fpc->clk[FSL_PWM_CLK_CNTEN] =
	450	devm_clk_get(fpc->chip.dev, "ftm_cnt_clk_en");
	451	if (IS_ERR(fpc->clk[FSL_PWM_CLK_CNTEN]))
	452	return PTR_ERR(fpc->clk[FSL_PWM_CLK_CNTEN]);
	453
	454	fpc->chip.ops = &fsl_pwm_ops;
	455	fpc->chip.of_xlate = of_pwm_xlate_with_flags;
	456	fpc->chip.of_pwm_n_cells = 3;
	457	fpc->chip.base = -1;
	458	fpc->chip.npwm = 8;
39fd3f99	459	fpc->chip.can_sleep = true;
b505183b XL	460
	461	ret = pwmchip_add(&fpc->chip);
	462	if (ret < 0) {
	463	dev_err(&pdev->dev, "failed to add PWM chip: %d\n", ret);
	464	return ret;
	465	}
	466
	467	platform_set_drvdata(pdev, fpc);
	468
	469	return fsl_pwm_init(fpc);
	470	}
	471
	472	static int fsl_pwm_remove(struct platform_device *pdev)
	473	{
	474	struct fsl_pwm_chip *fpc = platform_get_drvdata(pdev);
	475
	476	return pwmchip_remove(&fpc->chip);
	477	}
	478
	479	static const struct of_device_id fsl_pwm_dt_ids[] = {
	480	{ .compatible = "fsl,vf610-ftm-pwm", },
	481	{ /* sentinel */ }
	482	};
	483	MODULE_DEVICE_TABLE(of, fsl_pwm_dt_ids);
	484
	485	static struct platform_driver fsl_pwm_driver = {
	486	.driver = {
	487	.name = "fsl-ftm-pwm",
	488	.of_match_table = fsl_pwm_dt_ids,
	489	},
	490	.probe = fsl_pwm_probe,
	491	.remove = fsl_pwm_remove,
	492	};
	493	module_platform_driver(fsl_pwm_driver);
	494
	495	MODULE_DESCRIPTION("Freescale FlexTimer Module PWM Driver");
	496	MODULE_AUTHOR("Xiubo Li <Li.Xiubo@freescale.com>");
	497	MODULE_ALIAS("platform:fsl-ftm-pwm");
	498	MODULE_LICENSE("GPL");