[linux.git] / drivers / pwm / pwm-clps711x.c

/*
 * Cirrus Logic CLPS711X PWM driver
 *
 * Copyright (C) 2014 Alexander Shiyan <[email protected]>
 *
 * 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/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pwm.h>

struct clps711x_chip {
	struct pwm_chip chip;
	void __iomem *pmpcon;
	struct clk *clk;
	spinlock_t lock;
};

static inline struct clps711x_chip *to_clps711x_chip(struct pwm_chip *chip)
{
	return container_of(chip, struct clps711x_chip, chip);
}

static void clps711x_pwm_update_val(struct clps711x_chip *priv, u32 n, u32 v)
{
	/* PWM0 - bits 4..7, PWM1 - bits 8..11 */
	u32 shift = (n + 1) * 4;
	unsigned long flags;
	u32 tmp;

	spin_lock_irqsave(&priv->lock, flags);

	tmp = readl(priv->pmpcon);
	tmp &= ~(0xf << shift);
	tmp |= v << shift;
	writel(tmp, priv->pmpcon);

	spin_unlock_irqrestore(&priv->lock, flags);
}

static unsigned int clps711x_get_duty(struct pwm_device *pwm, unsigned int v)
{
	/* Duty cycle 0..15 max */
	return DIV_ROUND_CLOSEST(v * 0xf, pwm_get_period(pwm));
}

static int clps711x_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
{
	struct clps711x_chip *priv = to_clps711x_chip(chip);
	unsigned int freq = clk_get_rate(priv->clk);

	if (!freq)
		return -EINVAL;

	/* Store constant period value */
	pwm->args.period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, freq);

	return 0;
}

static int clps711x_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
			       int duty_ns, int period_ns)
{
	struct clps711x_chip *priv = to_clps711x_chip(chip);
	unsigned int duty;

	if (period_ns != pwm_get_period(pwm))
		return -EINVAL;

	duty = clps711x_get_duty(pwm, duty_ns);
	clps711x_pwm_update_val(priv, pwm->hwpwm, duty);

	return 0;
}

static int clps711x_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
	struct clps711x_chip *priv = to_clps711x_chip(chip);
	unsigned int duty;

	duty = clps711x_get_duty(pwm, pwm_get_duty_cycle(pwm));
	clps711x_pwm_update_val(priv, pwm->hwpwm, duty);

	return 0;
}

static void clps711x_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
	struct clps711x_chip *priv = to_clps711x_chip(chip);

	clps711x_pwm_update_val(priv, pwm->hwpwm, 0);
}

static const struct pwm_ops clps711x_pwm_ops = {
	.request = clps711x_pwm_request,
	.config = clps711x_pwm_config,
	.enable = clps711x_pwm_enable,
	.disable = clps711x_pwm_disable,
	.owner = THIS_MODULE,
};

static struct pwm_device *clps711x_pwm_xlate(struct pwm_chip *chip,
					     const struct of_phandle_args *args)
{
	if (args->args[0] >= chip->npwm)
		return ERR_PTR(-EINVAL);

	return pwm_request_from_chip(chip, args->args[0], NULL);
}

static int clps711x_pwm_probe(struct platform_device *pdev)
{
	struct clps711x_chip *priv;
	struct resource *res;

	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	priv->pmpcon = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(priv->pmpcon))
		return PTR_ERR(priv->pmpcon);

	priv->clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(priv->clk))
		return PTR_ERR(priv->clk);

	priv->chip.ops = &clps711x_pwm_ops;
	priv->chip.dev = &pdev->dev;
	priv->chip.base = -1;
	priv->chip.npwm = 2;
	priv->chip.of_xlate = clps711x_pwm_xlate;
	priv->chip.of_pwm_n_cells = 1;

	spin_lock_init(&priv->lock);

	platform_set_drvdata(pdev, priv);

	return pwmchip_add(&priv->chip);
}

static int clps711x_pwm_remove(struct platform_device *pdev)
{
	struct clps711x_chip *priv = platform_get_drvdata(pdev);

	return pwmchip_remove(&priv->chip);
}

static const struct of_device_id __maybe_unused clps711x_pwm_dt_ids[] = {
	{ .compatible = "cirrus,ep7209-pwm", },
	{ }
};
MODULE_DEVICE_TABLE(of, clps711x_pwm_dt_ids);

static struct platform_driver clps711x_pwm_driver = {
	.driver = {
		.name = "clps711x-pwm",
		.of_match_table = of_match_ptr(clps711x_pwm_dt_ids),
	},
	.probe = clps711x_pwm_probe,
	.remove = clps711x_pwm_remove,
};
module_platform_driver(clps711x_pwm_driver);

MODULE_AUTHOR("Alexander Shiyan <[email protected]>");
MODULE_DESCRIPTION("Cirrus Logic CLPS711X PWM driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
7eb3f6ff AS	1	/*
	2	* Cirrus Logic CLPS711X PWM driver
	3	*
	4	* Copyright (C) 2014 Alexander Shiyan <[email protected]>
	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/io.h>
	14	#include <linux/module.h>
	15	#include <linux/of.h>
	16	#include <linux/platform_device.h>
	17	#include <linux/pwm.h>
	18
	19	struct clps711x_chip {
	20	struct pwm_chip chip;
	21	void __iomem *pmpcon;
	22	struct clk *clk;
	23	spinlock_t lock;
	24	};
	25
	26	static inline struct clps711x_chip to_clps711x_chip(struct pwm_chip chip)
	27	{
	28	return container_of(chip, struct clps711x_chip, chip);
	29	}
	30
	31	static void clps711x_pwm_update_val(struct clps711x_chip *priv, u32 n, u32 v)
	32	{
	33	/* PWM0 - bits 4..7, PWM1 - bits 8..11 */
	34	u32 shift = (n + 1) * 4;
	35	unsigned long flags;
	36	u32 tmp;
	37
	38	spin_lock_irqsave(&priv->lock, flags);
	39
	40	tmp = readl(priv->pmpcon);
	41	tmp &= ~(0xf << shift);
	42	tmp \|= v << shift;
	43	writel(tmp, priv->pmpcon);
	44
	45	spin_unlock_irqrestore(&priv->lock, flags);
	46	}
	47
	48	static unsigned int clps711x_get_duty(struct pwm_device *pwm, unsigned int v)
	49	{
	50	/* Duty cycle 0..15 max */
	51	return DIV_ROUND_CLOSEST(v * 0xf, pwm_get_period(pwm));
	52	}
	53
	54	static int clps711x_pwm_request(struct pwm_chip chip, struct pwm_device pwm)
	55	{
	56	struct clps711x_chip *priv = to_clps711x_chip(chip);
	57	unsigned int freq = clk_get_rate(priv->clk);
	58
	59	if (!freq)
	60	return -EINVAL;
	61
	62	/* Store constant period value */
e39c0df1	63	pwm->args.period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, freq);
7eb3f6ff AS	64
	65	return 0;
	66	}
	67
	68	static int clps711x_pwm_config(struct pwm_chip chip, struct pwm_device pwm,
	69	int duty_ns, int period_ns)
	70	{
	71	struct clps711x_chip *priv = to_clps711x_chip(chip);
	72	unsigned int duty;
	73
	74	if (period_ns != pwm_get_period(pwm))
	75	return -EINVAL;
	76
	77	duty = clps711x_get_duty(pwm, duty_ns);
	78	clps711x_pwm_update_val(priv, pwm->hwpwm, duty);
	79
	80	return 0;
	81	}
	82
	83	static int clps711x_pwm_enable(struct pwm_chip chip, struct pwm_device pwm)
	84	{
	85	struct clps711x_chip *priv = to_clps711x_chip(chip);
	86	unsigned int duty;
	87
	88	duty = clps711x_get_duty(pwm, pwm_get_duty_cycle(pwm));
	89	clps711x_pwm_update_val(priv, pwm->hwpwm, duty);
	90
	91	return 0;
	92	}
	93
	94	static void clps711x_pwm_disable(struct pwm_chip chip, struct pwm_device pwm)
	95	{
	96	struct clps711x_chip *priv = to_clps711x_chip(chip);
	97
	98	clps711x_pwm_update_val(priv, pwm->hwpwm, 0);
	99	}
	100
	101	static const struct pwm_ops clps711x_pwm_ops = {
	102	.request = clps711x_pwm_request,
	103	.config = clps711x_pwm_config,
	104	.enable = clps711x_pwm_enable,
	105	.disable = clps711x_pwm_disable,
	106	.owner = THIS_MODULE,
	107	};
	108
	109	static struct pwm_device clps711x_pwm_xlate(struct pwm_chip chip,
	110	const struct of_phandle_args *args)
	111	{
	112	if (args->args[0] >= chip->npwm)
	113	return ERR_PTR(-EINVAL);
	114
	115	return pwm_request_from_chip(chip, args->args[0], NULL);
	116	}
	117
	118	static int clps711x_pwm_probe(struct platform_device *pdev)
	119	{
	120	struct clps711x_chip *priv;
	121	struct resource *res;
	122
	123	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
	124	if (!priv)
	125	return -ENOMEM;
	126
	127	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
128	priv->pmpcon = devm_ioremap_resource(&pdev->dev, res);
129	if (IS_ERR(priv->pmpcon))
130	return PTR_ERR(priv->pmpcon);
131
132	priv->clk = devm_clk_get(&pdev->dev, NULL);
133	if (IS_ERR(priv->clk))
134	return PTR_ERR(priv->clk);
135
136	priv->chip.ops = &clps711x_pwm_ops;
137	priv->chip.dev = &pdev->dev;
138	priv->chip.base = -1;
139	priv->chip.npwm = 2;
140	priv->chip.of_xlate = clps711x_pwm_xlate;
141	priv->chip.of_pwm_n_cells = 1;
142
143	spin_lock_init(&priv->lock);
144
145	platform_set_drvdata(pdev, priv);
146
147	return pwmchip_add(&priv->chip);
148	}
149
150	static int clps711x_pwm_remove(struct platform_device *pdev)
151	{
152	struct clps711x_chip *priv = platform_get_drvdata(pdev);
153
154	return pwmchip_remove(&priv->chip);
155	}
156
157	static const struct of_device_id __maybe_unused clps711x_pwm_dt_ids[] = {
ba60ae1d	158	{ .compatible = "cirrus,ep7209-pwm", },
7eb3f6ff AS	159	{ }
	160	};
	161	MODULE_DEVICE_TABLE(of, clps711x_pwm_dt_ids);
	162
	163	static struct platform_driver clps711x_pwm_driver = {
	164	.driver = {
	165	.name = "clps711x-pwm",
7eb3f6ff AS	166	.of_match_table = of_match_ptr(clps711x_pwm_dt_ids),
	167	},
	168	.probe = clps711x_pwm_probe,
	169	.remove = clps711x_pwm_remove,
	170	};
	171	module_platform_driver(clps711x_pwm_driver);
	172
	173	MODULE_AUTHOR("Alexander Shiyan <[email protected]>");
	174	MODULE_DESCRIPTION("Cirrus Logic CLPS711X PWM driver");
	175	MODULE_LICENSE("GPL");