[linux-block.git] / drivers / gpio / gpio-xra1403.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * GPIO driver for EXAR XRA1403 16-bit GPIO expander
 *
 * Copyright (c) 2017, General Electric Company
 */

#include <linux/bitops.h>
#include <linux/gpio/driver.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>
#include <linux/seq_file.h>
#include <linux/spi/spi.h>
#include <linux/regmap.h>

/* XRA1403 registers */
#define XRA_GSR   0x00 /* GPIO State */
#define XRA_OCR   0x02 /* Output Control */
#define XRA_PIR   0x04 /* Input Polarity Inversion */
#define XRA_GCR   0x06 /* GPIO Configuration */
#define XRA_PUR   0x08 /* Input Internal Pull-up Resistor Enable/Disable */
#define XRA_IER   0x0A /* Input Interrupt Enable */
#define XRA_TSCR  0x0C /* Output Three-State Control */
#define XRA_ISR   0x0E /* Input Interrupt Status */
#define XRA_REIR  0x10 /* Input Rising Edge Interrupt Enable */
#define XRA_FEIR  0x12 /* Input Falling Edge Interrupt Enable */
#define XRA_IFR   0x14 /* Input Filter Enable/Disable */
#define XRA_LAST  0x15 /* Bounds */

struct xra1403 {
	struct gpio_chip  chip;
	struct regmap     *regmap;
};

static const struct regmap_config xra1403_regmap_cfg = {
		.reg_bits = 7,
		.pad_bits = 1,
		.val_bits = 8,

		.max_register = XRA_LAST,
};

static unsigned int to_reg(unsigned int reg, unsigned int offset)
{
	return reg + (offset > 7);
}

static int xra1403_direction_input(struct gpio_chip *chip, unsigned int offset)
{
	struct xra1403 *xra = gpiochip_get_data(chip);

	return regmap_update_bits(xra->regmap, to_reg(XRA_GCR, offset),
			BIT(offset % 8), BIT(offset % 8));
}

static int xra1403_direction_output(struct gpio_chip *chip, unsigned int offset,
				    int value)
{
	int ret;
	struct xra1403 *xra = gpiochip_get_data(chip);

	ret = regmap_update_bits(xra->regmap, to_reg(XRA_GCR, offset),
			BIT(offset % 8), 0);
	if (ret)
		return ret;

	ret = regmap_update_bits(xra->regmap, to_reg(XRA_OCR, offset),
			BIT(offset % 8), value ? BIT(offset % 8) : 0);

	return ret;
}

static int xra1403_get_direction(struct gpio_chip *chip, unsigned int offset)
{
	int ret;
	unsigned int val;
	struct xra1403 *xra = gpiochip_get_data(chip);

	ret = regmap_read(xra->regmap, to_reg(XRA_GCR, offset), &val);
	if (ret)
		return ret;

	if (val & BIT(offset % 8))
		return GPIO_LINE_DIRECTION_IN;

	return GPIO_LINE_DIRECTION_OUT;
}

static int xra1403_get(struct gpio_chip *chip, unsigned int offset)
{
	int ret;
	unsigned int val;
	struct xra1403 *xra = gpiochip_get_data(chip);

	ret = regmap_read(xra->regmap, to_reg(XRA_GSR, offset), &val);
	if (ret)
		return ret;

	return !!(val & BIT(offset % 8));
}

static void xra1403_set(struct gpio_chip *chip, unsigned int offset, int value)
{
	int ret;
	struct xra1403 *xra = gpiochip_get_data(chip);

	ret = regmap_update_bits(xra->regmap, to_reg(XRA_OCR, offset),
			BIT(offset % 8), value ? BIT(offset % 8) : 0);
	if (ret)
		dev_err(chip->parent, "Failed to set pin: %d, ret: %d\n",
				offset, ret);
}

#ifdef CONFIG_DEBUG_FS
static void xra1403_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
	int reg;
	struct xra1403 *xra = gpiochip_get_data(chip);
	int value[XRA_LAST];
	int i;
	const char *label;
	unsigned int gcr;
	unsigned int gsr;

	seq_puts(s, "xra reg:");
	for (reg = 0; reg <= XRA_LAST; reg++)
		seq_printf(s, " %2.2x", reg);
	seq_puts(s, "\n  value:");
	for (reg = 0; reg < XRA_LAST; reg++) {
		regmap_read(xra->regmap, reg, &value[reg]);
		seq_printf(s, " %2.2x", value[reg]);
	}
	seq_puts(s, "\n");

	gcr = value[XRA_GCR + 1] << 8 | value[XRA_GCR];
	gsr = value[XRA_GSR + 1] << 8 | value[XRA_GSR];
	for_each_requested_gpio(chip, i, label) {
		seq_printf(s, " gpio-%-3d (%-12s) %s %s\n",
			   chip->base + i, label,
			   (gcr & BIT(i)) ? "in" : "out",
			   (gsr & BIT(i)) ? "hi" : "lo");
	}
}
#else
#define xra1403_dbg_show NULL
#endif

static int xra1403_probe(struct spi_device *spi)
{
	struct xra1403 *xra;
	struct gpio_desc *reset_gpio;
	int ret;

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

	/* bring the chip out of reset if reset pin is provided*/
	reset_gpio = devm_gpiod_get_optional(&spi->dev, "reset", GPIOD_OUT_LOW);
	if (IS_ERR(reset_gpio))
		dev_warn(&spi->dev, "Could not get reset-gpios\n");

	xra->chip.direction_input = xra1403_direction_input;
	xra->chip.direction_output = xra1403_direction_output;
	xra->chip.get_direction = xra1403_get_direction;
	xra->chip.get = xra1403_get;
	xra->chip.set = xra1403_set;

	xra->chip.dbg_show = xra1403_dbg_show;

	xra->chip.ngpio = 16;
	xra->chip.label = "xra1403";

	xra->chip.base = -1;
	xra->chip.can_sleep = true;
	xra->chip.parent = &spi->dev;
	xra->chip.owner = THIS_MODULE;

	xra->regmap = devm_regmap_init_spi(spi, &xra1403_regmap_cfg);
	if (IS_ERR(xra->regmap)) {
		ret = PTR_ERR(xra->regmap);
		dev_err(&spi->dev, "Failed to allocate regmap: %d\n", ret);
		return ret;
	}

	return devm_gpiochip_add_data(&spi->dev, &xra->chip, xra);
}

static const struct spi_device_id xra1403_ids[] = {
	{ "xra1403" },
	{},
};
MODULE_DEVICE_TABLE(spi, xra1403_ids);

static const struct of_device_id xra1403_spi_of_match[] __maybe_unused = {
	{ .compatible = "exar,xra1403" },
	{},
};
MODULE_DEVICE_TABLE(of, xra1403_spi_of_match);

static struct spi_driver xra1403_driver = {
	.probe    = xra1403_probe,
	.id_table = xra1403_ids,
	.driver   = {
		.name           = "xra1403",
		.of_match_table = of_match_ptr(xra1403_spi_of_match),
	},
};

module_spi_driver(xra1403_driver);

MODULE_AUTHOR("Nandor Han <nandor.han@ge.com>");
MODULE_AUTHOR("Semi Malinen <semi.malinen@ge.com>");
MODULE_DESCRIPTION("GPIO expander driver for EXAR XRA1403");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
9952f691	1	// SPDX-License-Identifier: GPL-2.0-only
5704520d NH	2	/*
	3	* GPIO driver for EXAR XRA1403 16-bit GPIO expander
	4	*
	5	* Copyright (c) 2017, General Electric Company
5704520d NH	6	*/
	7
	8	#include <linux/bitops.h>
	9	#include <linux/gpio/driver.h>
	10	#include <linux/kernel.h>
	11	#include <linux/module.h>
	12	#include <linux/mutex.h>
	13	#include <linux/of_device.h>
	14	#include <linux/of_gpio.h>
	15	#include <linux/seq_file.h>
	16	#include <linux/spi/spi.h>
	17	#include <linux/regmap.h>
	18
	19	/* XRA1403 registers */
	20	#define XRA_GSR 0x00 /* GPIO State */
	21	#define XRA_OCR 0x02 /* Output Control */
	22	#define XRA_PIR 0x04 /* Input Polarity Inversion */
	23	#define XRA_GCR 0x06 /* GPIO Configuration */
	24	#define XRA_PUR 0x08 /* Input Internal Pull-up Resistor Enable/Disable */
	25	#define XRA_IER 0x0A /* Input Interrupt Enable */
	26	#define XRA_TSCR 0x0C /* Output Three-State Control */
	27	#define XRA_ISR 0x0E /* Input Interrupt Status */
	28	#define XRA_REIR 0x10 /* Input Rising Edge Interrupt Enable */
	29	#define XRA_FEIR 0x12 /* Input Falling Edge Interrupt Enable */
	30	#define XRA_IFR 0x14 /* Input Filter Enable/Disable */
12f92ccc	31	#define XRA_LAST 0x15 /* Bounds */
5704520d NH	32
	33	struct xra1403 {
	34	struct gpio_chip chip;
	35	struct regmap *regmap;
	36	};
	37
	38	static const struct regmap_config xra1403_regmap_cfg = {
	39	.reg_bits = 7,
	40	.pad_bits = 1,
	41	.val_bits = 8,
	42
12f92ccc	43	.max_register = XRA_LAST,
5704520d NH	44	};
	45
	46	static unsigned int to_reg(unsigned int reg, unsigned int offset)
	47	{
	48	return reg + (offset > 7);
	49	}
	50
	51	static int xra1403_direction_input(struct gpio_chip *chip, unsigned int offset)
	52	{
	53	struct xra1403 *xra = gpiochip_get_data(chip);
	54
	55	return regmap_update_bits(xra->regmap, to_reg(XRA_GCR, offset),
	56	BIT(offset % 8), BIT(offset % 8));
	57	}
	58
	59	static int xra1403_direction_output(struct gpio_chip *chip, unsigned int offset,
	60	int value)
	61	{
	62	int ret;
	63	struct xra1403 *xra = gpiochip_get_data(chip);
	64
	65	ret = regmap_update_bits(xra->regmap, to_reg(XRA_GCR, offset),
	66	BIT(offset % 8), 0);
	67	if (ret)
	68	return ret;
	69
	70	ret = regmap_update_bits(xra->regmap, to_reg(XRA_OCR, offset),
	71	BIT(offset % 8), value ? BIT(offset % 8) : 0);
	72
	73	return ret;
	74	}
	75
	76	static int xra1403_get_direction(struct gpio_chip *chip, unsigned int offset)
	77	{
	78	int ret;
	79	unsigned int val;
	80	struct xra1403 *xra = gpiochip_get_data(chip);
	81
	82	ret = regmap_read(xra->regmap, to_reg(XRA_GCR, offset), &val);
	83	if (ret)
	84	return ret;
	85
e42615ec MV	86	if (val & BIT(offset % 8))
	87	return GPIO_LINE_DIRECTION_IN;
	88
	89	return GPIO_LINE_DIRECTION_OUT;
5704520d NH	90	}
	91
	92	static int xra1403_get(struct gpio_chip *chip, unsigned int offset)
	93	{
	94	int ret;
	95	unsigned int val;
	96	struct xra1403 *xra = gpiochip_get_data(chip);
	97
	98	ret = regmap_read(xra->regmap, to_reg(XRA_GSR, offset), &val);
	99	if (ret)
	100	return ret;
	101
	102	return !!(val & BIT(offset % 8));
	103	}
	104
	105	static void xra1403_set(struct gpio_chip *chip, unsigned int offset, int value)
	106	{
	107	int ret;
	108	struct xra1403 *xra = gpiochip_get_data(chip);
	109
	110	ret = regmap_update_bits(xra->regmap, to_reg(XRA_OCR, offset),
	111	BIT(offset % 8), value ? BIT(offset % 8) : 0);
	112	if (ret)
	113	dev_err(chip->parent, "Failed to set pin: %d, ret: %d\n",
	114	offset, ret);
	115	}
	116
	117	#ifdef CONFIG_DEBUG_FS
	118	static void xra1403_dbg_show(struct seq_file s, struct gpio_chip chip)
	119	{
	120	int reg;
	121	struct xra1403 *xra = gpiochip_get_data(chip);
12f92ccc	122	int value[XRA_LAST];
5704520d	123	int i;
7796cdc9	124	const char *label;
5704520d NH	125	unsigned int gcr;
	126	unsigned int gsr;
	127
	128	seq_puts(s, "xra reg:");
12f92ccc	129	for (reg = 0; reg <= XRA_LAST; reg++)
5704520d NH	130	seq_printf(s, " %2.2x", reg);
5704520d NH	131	seq_puts(s, "\n value:");
12f92ccc	132	for (reg = 0; reg < XRA_LAST; reg++) {
5704520d NH	133	regmap_read(xra->regmap, reg, &value[reg]);
	134	seq_printf(s, " %2.2x", value[reg]);
	135	}
	136	seq_puts(s, "\n");
	137
	138	gcr = value[XRA_GCR + 1] << 8 \| value[XRA_GCR];
	139	gsr = value[XRA_GSR + 1] << 8 \| value[XRA_GSR];
7796cdc9	140	for_each_requested_gpio(chip, i, label) {
5704520d NH	141	seq_printf(s, " gpio-%-3d (%-12s) %s %s\n",
	142	chip->base + i, label,
	143	(gcr & BIT(i)) ? "in" : "out",
	144	(gsr & BIT(i)) ? "hi" : "lo");
	145	}
	146	}
	147	#else
	148	#define xra1403_dbg_show NULL
	149	#endif
	150
	151	static int xra1403_probe(struct spi_device *spi)
	152	{
	153	struct xra1403 *xra;
	154	struct gpio_desc *reset_gpio;
	155	int ret;
	156
	157	xra = devm_kzalloc(&spi->dev, sizeof(*xra), GFP_KERNEL);
	158	if (!xra)
	159	return -ENOMEM;
	160
	161	/* bring the chip out of reset if reset pin is provided*/
	162	reset_gpio = devm_gpiod_get_optional(&spi->dev, "reset", GPIOD_OUT_LOW);
	163	if (IS_ERR(reset_gpio))
	164	dev_warn(&spi->dev, "Could not get reset-gpios\n");
	165
	166	xra->chip.direction_input = xra1403_direction_input;
	167	xra->chip.direction_output = xra1403_direction_output;
	168	xra->chip.get_direction = xra1403_get_direction;
	169	xra->chip.get = xra1403_get;
	170	xra->chip.set = xra1403_set;
	171
	172	xra->chip.dbg_show = xra1403_dbg_show;
	173
	174	xra->chip.ngpio = 16;
	175	xra->chip.label = "xra1403";
	176
	177	xra->chip.base = -1;
	178	xra->chip.can_sleep = true;
	179	xra->chip.parent = &spi->dev;
	180	xra->chip.owner = THIS_MODULE;
	181
	182	xra->regmap = devm_regmap_init_spi(spi, &xra1403_regmap_cfg);
	183	if (IS_ERR(xra->regmap)) {
	184	ret = PTR_ERR(xra->regmap);
	185	dev_err(&spi->dev, "Failed to allocate regmap: %d\n", ret);
	186	return ret;
	187	}
	188
0aa42370	189	return devm_gpiochip_add_data(&spi->dev, &xra->chip, xra);
5704520d NH	190	}
	191
	192	static const struct spi_device_id xra1403_ids[] = {
	193	{ "xra1403" },
	194	{},
	195	};
	196	MODULE_DEVICE_TABLE(spi, xra1403_ids);
	197
c5521bda	198	static const struct of_device_id xra1403_spi_of_match[] __maybe_unused = {
5704520d NH	199	{ .compatible = "exar,xra1403" },
	200	{},
	201	};
	202	MODULE_DEVICE_TABLE(of, xra1403_spi_of_match);
	203
	204	static struct spi_driver xra1403_driver = {
	205	.probe = xra1403_probe,
	206	.id_table = xra1403_ids,
	207	.driver = {
	208	.name = "xra1403",
	209	.of_match_table = of_match_ptr(xra1403_spi_of_match),
	210	},
	211	};
	212
	213	module_spi_driver(xra1403_driver);
	214
	215	MODULE_AUTHOR("Nandor Han <nandor.han@ge.com>");
	216	MODULE_AUTHOR("Semi Malinen <semi.malinen@ge.com>");
	217	MODULE_DESCRIPTION("GPIO expander driver for EXAR XRA1403");
	218	MODULE_LICENSE("GPL v2");