[mirror_ubuntu-hirsute-kernel.git] / drivers / gpio / gpio-exar.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * GPIO driver for Exar XR17V35X chip
 *
 * Copyright (C) 2015 Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
 */

#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/gpio/driver.h>
#include <linux/idr.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>

#define EXAR_OFFSET_MPIOLVL_LO 0x90
#define EXAR_OFFSET_MPIOSEL_LO 0x93
#define EXAR_OFFSET_MPIOLVL_HI 0x96
#define EXAR_OFFSET_MPIOSEL_HI 0x99

#define DRIVER_NAME "gpio_exar"

static DEFINE_IDA(ida_index);

struct exar_gpio_chip {
	struct gpio_chip gpio_chip;
	struct regmap *regmap;
	int index;
	char name[20];
	unsigned int first_pin;
};

static unsigned int
exar_offset_to_sel_addr(struct exar_gpio_chip *exar_gpio, unsigned int offset)
{
	return (offset + exar_gpio->first_pin) / 8 ? EXAR_OFFSET_MPIOSEL_HI
						   : EXAR_OFFSET_MPIOSEL_LO;
}

static unsigned int
exar_offset_to_lvl_addr(struct exar_gpio_chip *exar_gpio, unsigned int offset)
{
	return (offset + exar_gpio->first_pin) / 8 ? EXAR_OFFSET_MPIOLVL_HI
						   : EXAR_OFFSET_MPIOLVL_LO;
}

static unsigned int
exar_offset_to_bit(struct exar_gpio_chip *exar_gpio, unsigned int offset)
{
	return (offset + exar_gpio->first_pin) % 8;
}

static int exar_get_direction(struct gpio_chip *chip, unsigned int offset)
{
	struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
	unsigned int addr = exar_offset_to_sel_addr(exar_gpio, offset);
	unsigned int bit = exar_offset_to_bit(exar_gpio, offset);

	if (regmap_test_bits(exar_gpio->regmap, addr, BIT(bit)))
		return GPIO_LINE_DIRECTION_IN;

	return GPIO_LINE_DIRECTION_OUT;
}

static int exar_get_value(struct gpio_chip *chip, unsigned int offset)
{
	struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
	unsigned int addr = exar_offset_to_lvl_addr(exar_gpio, offset);
	unsigned int bit = exar_offset_to_bit(exar_gpio, offset);

	return !!(regmap_test_bits(exar_gpio->regmap, addr, BIT(bit)));
}

static void exar_set_value(struct gpio_chip *chip, unsigned int offset,
			   int value)
{
	struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
	unsigned int addr = exar_offset_to_lvl_addr(exar_gpio, offset);
	unsigned int bit = exar_offset_to_bit(exar_gpio, offset);

	if (value)
		regmap_set_bits(exar_gpio->regmap, addr, BIT(bit));
	else
		regmap_clear_bits(exar_gpio->regmap, addr, BIT(bit));
}

static int exar_direction_output(struct gpio_chip *chip, unsigned int offset,
				 int value)
{
	struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
	unsigned int addr = exar_offset_to_sel_addr(exar_gpio, offset);
	unsigned int bit = exar_offset_to_bit(exar_gpio, offset);

	exar_set_value(chip, offset, value);
	regmap_clear_bits(exar_gpio->regmap, addr, BIT(bit));

	return 0;
}

static int exar_direction_input(struct gpio_chip *chip, unsigned int offset)
{
	struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
	unsigned int addr = exar_offset_to_sel_addr(exar_gpio, offset);
	unsigned int bit = exar_offset_to_bit(exar_gpio, offset);

	regmap_set_bits(exar_gpio->regmap, addr, BIT(bit));

	return 0;
}

static void exar_devm_ida_free(void *data)
{
	struct exar_gpio_chip *exar_gpio = data;

	ida_free(&ida_index, exar_gpio->index);
}

static const struct regmap_config exar_regmap_config = {
	.name		= "exar-gpio",
	.reg_bits	= 16,
	.val_bits	= 8,
};

static int gpio_exar_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct pci_dev *pcidev = to_pci_dev(dev->parent);
	struct exar_gpio_chip *exar_gpio;
	u32 first_pin, ngpios;
	void __iomem *p;
	int index, ret;

	/*
	 * The UART driver must have mapped region 0 prior to registering this
	 * device - use it.
	 */
	p = pcim_iomap_table(pcidev)[0];
	if (!p)
		return -ENOMEM;

	ret = device_property_read_u32(dev, "exar,first-pin", &first_pin);
	if (ret)
		return ret;

	ret = device_property_read_u32(dev, "ngpios", &ngpios);
	if (ret)
		return ret;

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

	/*
	 * We don't need to check the return values of mmio regmap operations (unless
	 * the regmap has a clock attached which is not the case here).
	 */
	exar_gpio->regmap = devm_regmap_init_mmio(dev, p, &exar_regmap_config);
	if (IS_ERR(exar_gpio->regmap))
		return PTR_ERR(exar_gpio->regmap);

	index = ida_alloc(&ida_index, GFP_KERNEL);
	if (index < 0)
		return index;

	ret = devm_add_action_or_reset(dev, exar_devm_ida_free, exar_gpio);
	if (ret)
		return ret;

	sprintf(exar_gpio->name, "exar_gpio%d", index);
	exar_gpio->gpio_chip.label = exar_gpio->name;
	exar_gpio->gpio_chip.parent = dev;
	exar_gpio->gpio_chip.direction_output = exar_direction_output;
	exar_gpio->gpio_chip.direction_input = exar_direction_input;
	exar_gpio->gpio_chip.get_direction = exar_get_direction;
	exar_gpio->gpio_chip.get = exar_get_value;
	exar_gpio->gpio_chip.set = exar_set_value;
	exar_gpio->gpio_chip.base = -1;
	exar_gpio->gpio_chip.ngpio = ngpios;
	exar_gpio->index = index;
	exar_gpio->first_pin = first_pin;

	ret = devm_gpiochip_add_data(dev, &exar_gpio->gpio_chip, exar_gpio);
	if (ret)
		return ret;

	platform_set_drvdata(pdev, exar_gpio);

	return 0;
}

static struct platform_driver gpio_exar_driver = {
	.probe	= gpio_exar_probe,
	.driver	= {
		.name = DRIVER_NAME,
	},
};

module_platform_driver(gpio_exar_driver);

MODULE_ALIAS("platform:" DRIVER_NAME);
MODULE_DESCRIPTION("Exar GPIO driver");
MODULE_AUTHOR("Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>");
MODULE_LICENSE("GPL");
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
6596e59e SM	2	/*
	3	* GPIO driver for Exar XR17V35X chip
	4	*
	5	* Copyright (C) 2015 Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
6596e59e	6	*/
1bfaf129	7
6596e59e SM	8	#include <linux/bitops.h>
	9	#include <linux/device.h>
	10	#include <linux/gpio/driver.h>
26ced453	11	#include <linux/idr.h>
6596e59e SM	12	#include <linux/init.h>
	13	#include <linux/kernel.h>
	14	#include <linux/module.h>
	15	#include <linux/pci.h>
	16	#include <linux/platform_device.h>
36fb7218	17	#include <linux/regmap.h>
6596e59e SM	18
	19	#define EXAR_OFFSET_MPIOLVL_LO 0x90
	20	#define EXAR_OFFSET_MPIOSEL_LO 0x93
	21	#define EXAR_OFFSET_MPIOLVL_HI 0x96
	22	#define EXAR_OFFSET_MPIOSEL_HI 0x99
	23
	24	#define DRIVER_NAME "gpio_exar"
	25
	26	static DEFINE_IDA(ida_index);
	27
	28	struct exar_gpio_chip {
	29	struct gpio_chip gpio_chip;
36fb7218	30	struct regmap *regmap;
6596e59e	31	int index;
6596e59e	32	char name[20];
380b1e2f	33	unsigned int first_pin;
6596e59e SM	34	};
6596e59e SM	35
696868d0 BG	36	static unsigned int
	37	exar_offset_to_sel_addr(struct exar_gpio_chip *exar_gpio, unsigned int offset)
	38	{
	39	return (offset + exar_gpio->first_pin) / 8 ? EXAR_OFFSET_MPIOSEL_HI
	40	: EXAR_OFFSET_MPIOSEL_LO;
	41	}
	42
	43	static unsigned int
	44	exar_offset_to_lvl_addr(struct exar_gpio_chip *exar_gpio, unsigned int offset)
	45	{
	46	return (offset + exar_gpio->first_pin) / 8 ? EXAR_OFFSET_MPIOLVL_HI
	47	: EXAR_OFFSET_MPIOLVL_LO;
	48	}
	49
	50	static unsigned int
	51	exar_offset_to_bit(struct exar_gpio_chip *exar_gpio, unsigned int offset)
	52	{
	53	return (offset + exar_gpio->first_pin) % 8;
	54	}
	55
6596e59e SM	56	static int exar_get_direction(struct gpio_chip *chip, unsigned int offset)
6596e59e SM	57	{
380b1e2f	58	struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
696868d0 BG	59	unsigned int addr = exar_offset_to_sel_addr(exar_gpio, offset);
696868d0 BG	60	unsigned int bit = exar_offset_to_bit(exar_gpio, offset);
6596e59e	61
36fb7218	62	if (regmap_test_bits(exar_gpio->regmap, addr, BIT(bit)))
e42615ec MV	63	return GPIO_LINE_DIRECTION_IN;
	64
	65	return GPIO_LINE_DIRECTION_OUT;
6596e59e SM	66	}
	67
	68	static int exar_get_value(struct gpio_chip *chip, unsigned int offset)
	69	{
380b1e2f	70	struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
696868d0 BG	71	unsigned int addr = exar_offset_to_lvl_addr(exar_gpio, offset);
696868d0 BG	72	unsigned int bit = exar_offset_to_bit(exar_gpio, offset);
6596e59e	73
36fb7218	74	return !!(regmap_test_bits(exar_gpio->regmap, addr, BIT(bit)));
6596e59e SM	75	}
	76
	77	static void exar_set_value(struct gpio_chip *chip, unsigned int offset,
	78	int value)
	79	{
380b1e2f	80	struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
696868d0 BG	81	unsigned int addr = exar_offset_to_lvl_addr(exar_gpio, offset);
696868d0 BG	82	unsigned int bit = exar_offset_to_bit(exar_gpio, offset);
6596e59e	83
36fb7218 BG	84	if (value)
	85	regmap_set_bits(exar_gpio->regmap, addr, BIT(bit));
	86	else
	87	regmap_clear_bits(exar_gpio->regmap, addr, BIT(bit));
6596e59e SM	88	}
6596e59e SM	89
eddeae07 AL	90	static int exar_direction_output(struct gpio_chip *chip, unsigned int offset,
	91	int value)
	92	{
36fb7218 BG	93	struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
	94	unsigned int addr = exar_offset_to_sel_addr(exar_gpio, offset);
	95	unsigned int bit = exar_offset_to_bit(exar_gpio, offset);
	96
eddeae07	97	exar_set_value(chip, offset, value);
36fb7218 BG	98	regmap_clear_bits(exar_gpio->regmap, addr, BIT(bit));
	99
	100	return 0;
eddeae07 AL	101	}
	102
	103	static int exar_direction_input(struct gpio_chip *chip, unsigned int offset)
	104	{
36fb7218 BG	105	struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip);
	106	unsigned int addr = exar_offset_to_sel_addr(exar_gpio, offset);
	107	unsigned int bit = exar_offset_to_bit(exar_gpio, offset);
	108
	109	regmap_set_bits(exar_gpio->regmap, addr, BIT(bit));
	110
	111	return 0;
eddeae07 AL	112	}
eddeae07 AL	113
5300ebb6 BG	114	static void exar_devm_ida_free(void *data)
	115	{
	116	struct exar_gpio_chip *exar_gpio = data;
	117
	118	ida_free(&ida_index, exar_gpio->index);
	119	}
	120
36fb7218 BG	121	static const struct regmap_config exar_regmap_config = {
	122	.name = "exar-gpio",
	123	.reg_bits = 16,
	124	.val_bits = 8,
	125	};
	126
6596e59e SM	127	static int gpio_exar_probe(struct platform_device *pdev)
6596e59e SM	128	{
0c2c7e13 BG	129	struct device *dev = &pdev->dev;
0c2c7e13 BG	130	struct pci_dev *pcidev = to_pci_dev(dev->parent);
6596e59e	131	struct exar_gpio_chip *exar_gpio;
380b1e2f	132	u32 first_pin, ngpios;
6596e59e SM	133	void __iomem *p;
	134	int index, ret;
	135
6596e59e	136	/*
8847f5f9 JK	137	* The UART driver must have mapped region 0 prior to registering this
8847f5f9 JK	138	* device - use it.
6596e59e	139	*/
8847f5f9	140	p = pcim_iomap_table(pcidev)[0];
6596e59e SM	141	if (!p)
	142	return -ENOMEM;
	143
0c2c7e13	144	ret = device_property_read_u32(dev, "exar,first-pin", &first_pin);
380b1e2f JK	145	if (ret)
	146	return ret;
	147
0c2c7e13	148	ret = device_property_read_u32(dev, "ngpios", &ngpios);
380b1e2f JK	149	if (ret)
	150	return ret;
	151
0c2c7e13	152	exar_gpio = devm_kzalloc(dev, sizeof(*exar_gpio), GFP_KERNEL);
6596e59e SM	153	if (!exar_gpio)
	154	return -ENOMEM;
	155
36fb7218 BG	156	/*
	157	* We don't need to check the return values of mmio regmap operations (unless
	158	* the regmap has a clock attached which is not the case here).
	159	*/
	160	exar_gpio->regmap = devm_regmap_init_mmio(dev, p, &exar_regmap_config);
	161	if (IS_ERR(exar_gpio->regmap))
	162	return PTR_ERR(exar_gpio->regmap);
6596e59e	163
8e27c2ae	164	index = ida_alloc(&ida_index, GFP_KERNEL);
36fb7218 BG	165	if (index < 0)
36fb7218 BG	166	return index;
6596e59e	167
5300ebb6 BG	168	ret = devm_add_action_or_reset(dev, exar_devm_ida_free, exar_gpio);
	169	if (ret)
	170	return ret;
	171
6596e59e SM	172	sprintf(exar_gpio->name, "exar_gpio%d", index);
6596e59e SM	173	exar_gpio->gpio_chip.label = exar_gpio->name;
0c2c7e13	174	exar_gpio->gpio_chip.parent = dev;
6596e59e SM	175	exar_gpio->gpio_chip.direction_output = exar_direction_output;
	176	exar_gpio->gpio_chip.direction_input = exar_direction_input;
	177	exar_gpio->gpio_chip.get_direction = exar_get_direction;
	178	exar_gpio->gpio_chip.get = exar_get_value;
	179	exar_gpio->gpio_chip.set = exar_set_value;
	180	exar_gpio->gpio_chip.base = -1;
380b1e2f	181	exar_gpio->gpio_chip.ngpio = ngpios;
6596e59e	182	exar_gpio->index = index;
380b1e2f	183	exar_gpio->first_pin = first_pin;
6596e59e	184
0c2c7e13	185	ret = devm_gpiochip_add_data(dev, &exar_gpio->gpio_chip, exar_gpio);
6596e59e	186	if (ret)
5300ebb6	187	return ret;
6596e59e SM	188
	189	platform_set_drvdata(pdev, exar_gpio);
	190
6596e59e SM	191	return 0;
	192	}
	193
	194	static struct platform_driver gpio_exar_driver = {
	195	.probe = gpio_exar_probe,
6596e59e SM	196	.driver = {
	197	.name = DRIVER_NAME,
	198	},
	199	};
	200
	201	module_platform_driver(gpio_exar_driver);
	202
	203	MODULE_ALIAS("platform:" DRIVER_NAME);
	204	MODULE_DESCRIPTION("Exar GPIO driver");
	205	MODULE_AUTHOR("Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>");
	206	MODULE_LICENSE("GPL");