1/*
  2 * GPIO Driver for Dialog DA9055 PMICs.
  3 *
  4 * Copyright(c) 2012 Dialog Semiconductor Ltd.
  5 *
  6 * Author: David Dajun Chen <dchen@diasemi.com>
  7 *
  8 *  This program is free software; you can redistribute  it and/or modify it
  9 *  under  the terms of  the GNU General  Public License as published by the
 10 *  Free Software Foundation;  either version 2 of the  License, or (at your
 11 *  option) any later version.
 12 *
 13 */
 14#include <linux/module.h>
 15#include <linux/platform_device.h>
 16#include <linux/gpio.h>
 17
 18#include <linux/mfd/da9055/core.h>
 19#include <linux/mfd/da9055/reg.h>
 20#include <linux/mfd/da9055/pdata.h>
 21
 22#define DA9055_VDD_IO			0x0
 23#define DA9055_PUSH_PULL		0x3
 24#define DA9055_ACT_LOW			0x0
 25#define DA9055_GPI			0x1
 26#define DA9055_PORT_MASK		0x3
 27#define DA9055_PORT_SHIFT(offset)	(4 * (offset % 2))
 28
 29#define DA9055_INPUT			DA9055_GPI
 30#define DA9055_OUTPUT			DA9055_PUSH_PULL
 31#define DA9055_IRQ_GPI0			3
 32
 33struct da9055_gpio {
 34	struct da9055 *da9055;
 35	struct gpio_chip gp;
 36};
 37
 38static inline struct da9055_gpio *to_da9055_gpio(struct gpio_chip *chip)
 39{
 40	return container_of(chip, struct da9055_gpio, gp);
 41}
 42
 43static int da9055_gpio_get(struct gpio_chip *gc, unsigned offset)
 44{
 45	struct da9055_gpio *gpio = to_da9055_gpio(gc);
 46	int gpio_direction = 0;
 47	int ret;
 48
 49	/* Get GPIO direction */
 50	ret = da9055_reg_read(gpio->da9055, (offset >> 1) + DA9055_REG_GPIO0_1);
 51	if (ret < 0)
 52		return ret;
 53
 54	gpio_direction = ret & (DA9055_PORT_MASK) << DA9055_PORT_SHIFT(offset);
 55	gpio_direction >>= DA9055_PORT_SHIFT(offset);
 56	switch (gpio_direction) {
 57	case DA9055_INPUT:
 58		ret = da9055_reg_read(gpio->da9055, DA9055_REG_STATUS_B);
 59		if (ret < 0)
 60			return ret;
 61		break;
 62	case DA9055_OUTPUT:
 63		ret = da9055_reg_read(gpio->da9055, DA9055_REG_GPIO_MODE0_2);
 64		if (ret < 0)
 65			return ret;
 66	}
 67
 68	return ret & (1 << offset);
 69
 70}
 71
 72static void da9055_gpio_set(struct gpio_chip *gc, unsigned offset, int value)
 73{
 74	struct da9055_gpio *gpio = to_da9055_gpio(gc);
 75
 76	da9055_reg_update(gpio->da9055,
 77			DA9055_REG_GPIO_MODE0_2,
 78			1 << offset,
 79			value << offset);
 80}
 81
 82static int da9055_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
 83{
 84	struct da9055_gpio *gpio = to_da9055_gpio(gc);
 85	unsigned char reg_byte;
 86
 87	reg_byte = (DA9055_ACT_LOW | DA9055_GPI)
 88				<< DA9055_PORT_SHIFT(offset);
 89
 90	return da9055_reg_update(gpio->da9055, (offset >> 1) +
 91				DA9055_REG_GPIO0_1,
 92				DA9055_PORT_MASK <<
 93				DA9055_PORT_SHIFT(offset),
 94				reg_byte);
 95}
 96
 97static int da9055_gpio_direction_output(struct gpio_chip *gc,
 98					unsigned offset, int value)
 99{
100	struct da9055_gpio *gpio = to_da9055_gpio(gc);
101	unsigned char reg_byte;
102	int ret;
103
104	reg_byte = (DA9055_VDD_IO | DA9055_PUSH_PULL)
105					<< DA9055_PORT_SHIFT(offset);
106
107	ret = da9055_reg_update(gpio->da9055, (offset >> 1) +
108				DA9055_REG_GPIO0_1,
109				DA9055_PORT_MASK <<
110				DA9055_PORT_SHIFT(offset),
111				reg_byte);
112	if (ret < 0)
113		return ret;
114
115	da9055_gpio_set(gc, offset, value);
116
117	return 0;
118}
119
120static int da9055_gpio_to_irq(struct gpio_chip *gc, u32 offset)
121{
122	struct da9055_gpio *gpio = to_da9055_gpio(gc);
123	struct da9055 *da9055 = gpio->da9055;
124
125	return regmap_irq_get_virq(da9055->irq_data,
126				  DA9055_IRQ_GPI0 + offset);
127}
128
129static struct gpio_chip reference_gp = {
130	.label = "da9055-gpio",
131	.owner = THIS_MODULE,
132	.get = da9055_gpio_get,
133	.set = da9055_gpio_set,
134	.direction_input = da9055_gpio_direction_input,
135	.direction_output = da9055_gpio_direction_output,
136	.to_irq = da9055_gpio_to_irq,
137	.can_sleep = true,
138	.ngpio = 3,
139	.base = -1,
140};
141
142static int da9055_gpio_probe(struct platform_device *pdev)
143{
144	struct da9055_gpio *gpio;
145	struct da9055_pdata *pdata;
146	int ret;
147
148	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
149	if (gpio == NULL)
150		return -ENOMEM;
151
152	gpio->da9055 = dev_get_drvdata(pdev->dev.parent);
153	pdata = dev_get_platdata(gpio->da9055->dev);
154
155	gpio->gp = reference_gp;
156	if (pdata && pdata->gpio_base)
157		gpio->gp.base = pdata->gpio_base;
158
159	ret = gpiochip_add(&gpio->gp);
160	if (ret < 0) {
161		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
162		goto err_mem;
163	}
164
165	platform_set_drvdata(pdev, gpio);
166
167	return 0;
168
169err_mem:
170	return ret;
171}
172
173static int da9055_gpio_remove(struct platform_device *pdev)
174{
175	struct da9055_gpio *gpio = platform_get_drvdata(pdev);
176
177	return gpiochip_remove(&gpio->gp);
178}
179
180static struct platform_driver da9055_gpio_driver = {
181	.probe = da9055_gpio_probe,
182	.remove = da9055_gpio_remove,
183	.driver = {
184		.name	= "da9055-gpio",
185		.owner	= THIS_MODULE,
186	},
187};
188
189static int __init da9055_gpio_init(void)
190{
191	return platform_driver_register(&da9055_gpio_driver);
192}
193subsys_initcall(da9055_gpio_init);
194
195static void __exit da9055_gpio_exit(void)
196{
197	platform_driver_unregister(&da9055_gpio_driver);
198}
199module_exit(da9055_gpio_exit);
200
201MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
202MODULE_DESCRIPTION("DA9055 GPIO Device Driver");
203MODULE_LICENSE("GPL");
204MODULE_ALIAS("platform:da9055-gpio");