[linux.git] / drivers / gpio / gpio-syscon.c

/*
 *  SYSCON GPIO 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/err.h>
#include <linux/gpio.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>

#define GPIO_SYSCON_FEAT_IN	BIT(0)
#define GPIO_SYSCON_FEAT_OUT	BIT(1)
#define GPIO_SYSCON_FEAT_DIR	BIT(2)

/* SYSCON driver is designed to use 32-bit wide registers */
#define SYSCON_REG_SIZE		(4)
#define SYSCON_REG_BITS		(SYSCON_REG_SIZE * 8)

/**
 * struct syscon_gpio_data - Configuration for the device.
 * compatible:		SYSCON driver compatible string.
 * flags:		Set of GPIO_SYSCON_FEAT_ flags:
 *			GPIO_SYSCON_FEAT_IN:	GPIOs supports input,
 *			GPIO_SYSCON_FEAT_OUT:	GPIOs supports output,
 *			GPIO_SYSCON_FEAT_DIR:	GPIOs supports switch direction.
 * bit_count:		Number of bits used as GPIOs.
 * dat_bit_offset:	Offset (in bits) to the first GPIO bit.
 * dir_bit_offset:	Optional offset (in bits) to the first bit to switch
 *			GPIO direction (Used with GPIO_SYSCON_FEAT_DIR flag).
 * set:		HW specific callback to assigns output value
 *			for signal "offset"
 */

struct syscon_gpio_data {
	const char	*compatible;
	unsigned int	flags;
	unsigned int	bit_count;
	unsigned int	dat_bit_offset;
	unsigned int	dir_bit_offset;
	void		(*set)(struct gpio_chip *chip,
			       unsigned offset, int value);
};

struct syscon_gpio_priv {
	struct gpio_chip		chip;
	struct regmap			*syscon;
	const struct syscon_gpio_data	*data;
	u32				dreg_offset;
	u32				dir_reg_offset;
};

static int syscon_gpio_get(struct gpio_chip *chip, unsigned offset)
{
	struct syscon_gpio_priv *priv = gpiochip_get_data(chip);
	unsigned int val, offs;
	int ret;

	offs = priv->dreg_offset + priv->data->dat_bit_offset + offset;

	ret = regmap_read(priv->syscon,
			  (offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE, &val);
	if (ret)
		return ret;

	return !!(val & BIT(offs % SYSCON_REG_BITS));
}

static void syscon_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
{
	struct syscon_gpio_priv *priv = gpiochip_get_data(chip);
	unsigned int offs;

	offs = priv->dreg_offset + priv->data->dat_bit_offset + offset;

	regmap_update_bits(priv->syscon,
			   (offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE,
			   BIT(offs % SYSCON_REG_BITS),
			   val ? BIT(offs % SYSCON_REG_BITS) : 0);
}

static int syscon_gpio_dir_in(struct gpio_chip *chip, unsigned offset)
{
	struct syscon_gpio_priv *priv = gpiochip_get_data(chip);

	if (priv->data->flags & GPIO_SYSCON_FEAT_DIR) {
		unsigned int offs;

		offs = priv->dir_reg_offset +
		       priv->data->dir_bit_offset + offset;

		regmap_update_bits(priv->syscon,
				   (offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE,
				   BIT(offs % SYSCON_REG_BITS), 0);
	}

	return 0;
}

static int syscon_gpio_dir_out(struct gpio_chip *chip, unsigned offset, int val)
{
	struct syscon_gpio_priv *priv = gpiochip_get_data(chip);

	if (priv->data->flags & GPIO_SYSCON_FEAT_DIR) {
		unsigned int offs;

		offs = priv->dir_reg_offset +
		       priv->data->dir_bit_offset + offset;

		regmap_update_bits(priv->syscon,
				   (offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE,
				   BIT(offs % SYSCON_REG_BITS),
				   BIT(offs % SYSCON_REG_BITS));
	}

	priv->data->set(chip, offset, val);

	return 0;
}

static const struct syscon_gpio_data clps711x_mctrl_gpio = {
	/* ARM CLPS711X SYSFLG1 Bits 8-10 */
	.compatible	= "cirrus,ep7209-syscon1",
	.flags		= GPIO_SYSCON_FEAT_IN,
	.bit_count	= 3,
	.dat_bit_offset	= 0x40 * 8 + 8,
};

#define KEYSTONE_LOCK_BIT BIT(0)

static void keystone_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
{
	struct syscon_gpio_priv *priv = gpiochip_get_data(chip);
	unsigned int offs;
	int ret;

	offs = priv->dreg_offset + priv->data->dat_bit_offset + offset;

	if (!val)
		return;

	ret = regmap_update_bits(
			priv->syscon,
			(offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE,
			BIT(offs % SYSCON_REG_BITS) | KEYSTONE_LOCK_BIT,
			BIT(offs % SYSCON_REG_BITS) | KEYSTONE_LOCK_BIT);
	if (ret < 0)
		dev_err(chip->parent, "gpio write failed ret(%d)\n", ret);
}

static const struct syscon_gpio_data keystone_dsp_gpio = {
	/* ARM Keystone 2 */
	.compatible	= NULL,
	.flags		= GPIO_SYSCON_FEAT_OUT,
	.bit_count	= 28,
	.dat_bit_offset	= 4,
	.set		= keystone_gpio_set,
};

static const struct of_device_id syscon_gpio_ids[] = {
	{
		.compatible	= "cirrus,ep7209-mctrl-gpio",
		.data		= &clps711x_mctrl_gpio,
	},
	{
		.compatible	= "ti,keystone-dsp-gpio",
		.data		= &keystone_dsp_gpio,
	},
	{ }
};
MODULE_DEVICE_TABLE(of, syscon_gpio_ids);

static int syscon_gpio_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	const struct of_device_id *of_id;
	struct syscon_gpio_priv *priv;
	struct device_node *np = dev->of_node;
	int ret;

	of_id = of_match_device(syscon_gpio_ids, dev);
	if (!of_id)
		return -ENODEV;

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

	priv->data = of_id->data;

	if (priv->data->compatible) {
		priv->syscon = syscon_regmap_lookup_by_compatible(
					priv->data->compatible);
		if (IS_ERR(priv->syscon))
			return PTR_ERR(priv->syscon);
	} else {
		priv->syscon =
			syscon_regmap_lookup_by_phandle(np, "gpio,syscon-dev");
		if (IS_ERR(priv->syscon))
			return PTR_ERR(priv->syscon);

		ret = of_property_read_u32_index(np, "gpio,syscon-dev", 1,
						 &priv->dreg_offset);
		if (ret)
			dev_err(dev, "can't read the data register offset!\n");

		priv->dreg_offset <<= 3;

		ret = of_property_read_u32_index(np, "gpio,syscon-dev", 2,
						 &priv->dir_reg_offset);
		if (ret)
			dev_dbg(dev, "can't read the dir register offset!\n");

		priv->dir_reg_offset <<= 3;
	}

	priv->chip.parent = dev;
	priv->chip.owner = THIS_MODULE;
	priv->chip.label = dev_name(dev);
	priv->chip.base = -1;
	priv->chip.ngpio = priv->data->bit_count;
	priv->chip.get = syscon_gpio_get;
	if (priv->data->flags & GPIO_SYSCON_FEAT_IN)
		priv->chip.direction_input = syscon_gpio_dir_in;
	if (priv->data->flags & GPIO_SYSCON_FEAT_OUT) {
		priv->chip.set = priv->data->set ? : syscon_gpio_set;
		priv->chip.direction_output = syscon_gpio_dir_out;
	}

	platform_set_drvdata(pdev, priv);

	return devm_gpiochip_add_data(&pdev->dev, &priv->chip, priv);
}

static struct platform_driver syscon_gpio_driver = {
	.driver	= {
		.name		= "gpio-syscon",
		.of_match_table	= syscon_gpio_ids,
	},
	.probe	= syscon_gpio_probe,
};
module_platform_driver(syscon_gpio_driver);

MODULE_AUTHOR("Alexander Shiyan <[email protected]>");
MODULE_DESCRIPTION("SYSCON GPIO driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
6a8a0c1d AS	1	/*
	2	* SYSCON GPIO 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/err.h>
	13	#include <linux/gpio.h>
	14	#include <linux/module.h>
	15	#include <linux/of.h>
	16	#include <linux/of_device.h>
	17	#include <linux/platform_device.h>
	18	#include <linux/regmap.h>
	19	#include <linux/mfd/syscon.h>
	20
	21	#define GPIO_SYSCON_FEAT_IN BIT(0)
	22	#define GPIO_SYSCON_FEAT_OUT BIT(1)
	23	#define GPIO_SYSCON_FEAT_DIR BIT(2)
	24
	25	/* SYSCON driver is designed to use 32-bit wide registers */
	26	#define SYSCON_REG_SIZE (4)
	27	#define SYSCON_REG_BITS (SYSCON_REG_SIZE * 8)
	28
	29	/**
	30	* struct syscon_gpio_data - Configuration for the device.
	31	* compatible: SYSCON driver compatible string.
	32	* flags: Set of GPIO_SYSCON_FEAT_ flags:
	33	* GPIO_SYSCON_FEAT_IN: GPIOs supports input,
	34	* GPIO_SYSCON_FEAT_OUT: GPIOs supports output,
	35	* GPIO_SYSCON_FEAT_DIR: GPIOs supports switch direction.
	36	* bit_count: Number of bits used as GPIOs.
	37	* dat_bit_offset: Offset (in bits) to the first GPIO bit.
	38	* dir_bit_offset: Optional offset (in bits) to the first bit to switch
	39	* GPIO direction (Used with GPIO_SYSCON_FEAT_DIR flag).
2c341d62 GS	40	* set: HW specific callback to assigns output value
2c341d62 GS	41	* for signal "offset"
6a8a0c1d AS	42	*/
	43
	44	struct syscon_gpio_data {
	45	const char *compatible;
	46	unsigned int flags;
	47	unsigned int bit_count;
	48	unsigned int dat_bit_offset;
	49	unsigned int dir_bit_offset;
2c341d62 GS	50	void (set)(struct gpio_chip chip,
2c341d62 GS	51	unsigned offset, int value);
6a8a0c1d AS	52	};
	53
	54	struct syscon_gpio_priv {
	55	struct gpio_chip chip;
	56	struct regmap *syscon;
	57	const struct syscon_gpio_data *data;
5a3e3f88 GS	58	u32 dreg_offset;
5a3e3f88 GS	59	u32 dir_reg_offset;
6a8a0c1d AS	60	};
6a8a0c1d AS	61
6a8a0c1d AS	62	static int syscon_gpio_get(struct gpio_chip *chip, unsigned offset)
6a8a0c1d AS	63	{
d27ad7a8	64	struct syscon_gpio_priv *priv = gpiochip_get_data(chip);
5a3e3f88	65	unsigned int val, offs;
6a8a0c1d AS	66	int ret;
6a8a0c1d AS	67
5a3e3f88 GS	68	offs = priv->dreg_offset + priv->data->dat_bit_offset + offset;
5a3e3f88 GS	69
6a8a0c1d AS	70	ret = regmap_read(priv->syscon,
	71	(offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE, &val);
	72	if (ret)
	73	return ret;
	74
	75	return !!(val & BIT(offs % SYSCON_REG_BITS));
	76	}
	77
	78	static void syscon_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
	79	{
d27ad7a8	80	struct syscon_gpio_priv *priv = gpiochip_get_data(chip);
5a3e3f88 GS	81	unsigned int offs;
	82
	83	offs = priv->dreg_offset + priv->data->dat_bit_offset + offset;
6a8a0c1d AS	84
	85	regmap_update_bits(priv->syscon,
	86	(offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE,
	87	BIT(offs % SYSCON_REG_BITS),
	88	val ? BIT(offs % SYSCON_REG_BITS) : 0);
	89	}
	90
	91	static int syscon_gpio_dir_in(struct gpio_chip *chip, unsigned offset)
	92	{
d27ad7a8	93	struct syscon_gpio_priv *priv = gpiochip_get_data(chip);
6a8a0c1d AS	94
6a8a0c1d AS	95	if (priv->data->flags & GPIO_SYSCON_FEAT_DIR) {
5a3e3f88 GS	96	unsigned int offs;
	97
	98	offs = priv->dir_reg_offset +
	99	priv->data->dir_bit_offset + offset;
6a8a0c1d AS	100
	101	regmap_update_bits(priv->syscon,
	102	(offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE,
	103	BIT(offs % SYSCON_REG_BITS), 0);
	104	}
	105
	106	return 0;
	107	}
	108
	109	static int syscon_gpio_dir_out(struct gpio_chip *chip, unsigned offset, int val)
	110	{
d27ad7a8	111	struct syscon_gpio_priv *priv = gpiochip_get_data(chip);
6a8a0c1d AS	112
6a8a0c1d AS	113	if (priv->data->flags & GPIO_SYSCON_FEAT_DIR) {
5a3e3f88 GS	114	unsigned int offs;
	115
	116	offs = priv->dir_reg_offset +
	117	priv->data->dir_bit_offset + offset;
6a8a0c1d AS	118
	119	regmap_update_bits(priv->syscon,
	120	(offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE,
	121	BIT(offs % SYSCON_REG_BITS),
	122	BIT(offs % SYSCON_REG_BITS));
	123	}
	124
2c341d62	125	priv->data->set(chip, offset, val);
6a8a0c1d AS	126
	127	return 0;
	128	}
	129
	130	static const struct syscon_gpio_data clps711x_mctrl_gpio = {
	131	/* ARM CLPS711X SYSFLG1 Bits 8-10 */
2e607fca	132	.compatible = "cirrus,ep7209-syscon1",
6a8a0c1d AS	133	.flags = GPIO_SYSCON_FEAT_IN,
	134	.bit_count = 3,
	135	.dat_bit_offset = 0x40 * 8 + 8,
	136	};
	137
2134cb99 GS	138	#define KEYSTONE_LOCK_BIT BIT(0)
	139
	140	static void keystone_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
	141	{
d27ad7a8	142	struct syscon_gpio_priv *priv = gpiochip_get_data(chip);
2134cb99 GS	143	unsigned int offs;
	144	int ret;
	145
	146	offs = priv->dreg_offset + priv->data->dat_bit_offset + offset;
	147
	148	if (!val)
	149	return;
	150
	151	ret = regmap_update_bits(
	152	priv->syscon,
	153	(offs / SYSCON_REG_BITS) * SYSCON_REG_SIZE,
	154	BIT(offs % SYSCON_REG_BITS) \| KEYSTONE_LOCK_BIT,
	155	BIT(offs % SYSCON_REG_BITS) \| KEYSTONE_LOCK_BIT);
	156	if (ret < 0)
58383c78	157	dev_err(chip->parent, "gpio write failed ret(%d)\n", ret);
2134cb99 GS	158	}
	159
	160	static const struct syscon_gpio_data keystone_dsp_gpio = {
	161	/* ARM Keystone 2 */
	162	.compatible = NULL,
	163	.flags = GPIO_SYSCON_FEAT_OUT,
	164	.bit_count = 28,
	165	.dat_bit_offset = 4,
	166	.set = keystone_gpio_set,
	167	};
	168
6a8a0c1d AS	169	static const struct of_device_id syscon_gpio_ids[] = {
6a8a0c1d AS	170	{
2e607fca	171	.compatible = "cirrus,ep7209-mctrl-gpio",
6a8a0c1d AS	172	.data = &clps711x_mctrl_gpio,
6a8a0c1d AS	173	},
2134cb99 GS	174	{
	175	.compatible = "ti,keystone-dsp-gpio",
	176	.data = &keystone_dsp_gpio,
	177	},
6a8a0c1d AS	178	{ }
	179	};
	180	MODULE_DEVICE_TABLE(of, syscon_gpio_ids);
	181
	182	static int syscon_gpio_probe(struct platform_device *pdev)
	183	{
	184	struct device *dev = &pdev->dev;
853f0cb8	185	const struct of_device_id *of_id;
6a8a0c1d	186	struct syscon_gpio_priv *priv;
5a3e3f88 GS	187	struct device_node *np = dev->of_node;
5a3e3f88 GS	188	int ret;
6a8a0c1d	189
853f0cb8 LC	190	of_id = of_match_device(syscon_gpio_ids, dev);
	191	if (!of_id)
	192	return -ENODEV;
	193
6a8a0c1d AS	194	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
	195	if (!priv)
	196	return -ENOMEM;
	197
	198	priv->data = of_id->data;
	199
5a3e3f88 GS	200	if (priv->data->compatible) {
	201	priv->syscon = syscon_regmap_lookup_by_compatible(
	202	priv->data->compatible);
	203	if (IS_ERR(priv->syscon))
	204	return PTR_ERR(priv->syscon);
	205	} else {
	206	priv->syscon =
	207	syscon_regmap_lookup_by_phandle(np, "gpio,syscon-dev");
	208	if (IS_ERR(priv->syscon))
	209	return PTR_ERR(priv->syscon);
	210
	211	ret = of_property_read_u32_index(np, "gpio,syscon-dev", 1,
	212	&priv->dreg_offset);
	213	if (ret)
	214	dev_err(dev, "can't read the data register offset!\n");
	215
	216	priv->dreg_offset <<= 3;
	217
	218	ret = of_property_read_u32_index(np, "gpio,syscon-dev", 2,
	219	&priv->dir_reg_offset);
	220	if (ret)
c6ac19da	221	dev_dbg(dev, "can't read the dir register offset!\n");
5a3e3f88 GS	222
	223	priv->dir_reg_offset <<= 3;
	224	}
6a8a0c1d	225
58383c78	226	priv->chip.parent = dev;
6a8a0c1d AS	227	priv->chip.owner = THIS_MODULE;
	228	priv->chip.label = dev_name(dev);
	229	priv->chip.base = -1;
	230	priv->chip.ngpio = priv->data->bit_count;
	231	priv->chip.get = syscon_gpio_get;
	232	if (priv->data->flags & GPIO_SYSCON_FEAT_IN)
	233	priv->chip.direction_input = syscon_gpio_dir_in;
	234	if (priv->data->flags & GPIO_SYSCON_FEAT_OUT) {
2c341d62	235	priv->chip.set = priv->data->set ? : syscon_gpio_set;
6a8a0c1d AS	236	priv->chip.direction_output = syscon_gpio_dir_out;
	237	}
	238
	239	platform_set_drvdata(pdev, priv);
	240
94c683ab	241	return devm_gpiochip_add_data(&pdev->dev, &priv->chip, priv);
6a8a0c1d AS	242	}
	243
	244	static struct platform_driver syscon_gpio_driver = {
	245	.driver = {
	246	.name = "gpio-syscon",
6a8a0c1d AS	247	.of_match_table = syscon_gpio_ids,
	248	},
	249	.probe = syscon_gpio_probe,
6a8a0c1d AS	250	};
	251	module_platform_driver(syscon_gpio_driver);
	252
	253	MODULE_AUTHOR("Alexander Shiyan <[email protected]>");
	254	MODULE_DESCRIPTION("SYSCON GPIO driver");
	255	MODULE_LICENSE("GPL");