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 int da9055_gpio_get(struct gpio_chip *gc, unsigned offset)
 39{
 40	struct da9055_gpio *gpio = gpiochip_get_data(gc);
 41	int gpio_direction = 0;
 42	int ret;
 43
 44	/* Get GPIO direction */
 45	ret = da9055_reg_read(gpio->da9055, (offset >> 1) + DA9055_REG_GPIO0_1);
 46	if (ret < 0)
 47		return ret;
 48
 49	gpio_direction = ret & (DA9055_PORT_MASK) << DA9055_PORT_SHIFT(offset);
 50	gpio_direction >>= DA9055_PORT_SHIFT(offset);
 51	switch (gpio_direction) {
 52	case DA9055_INPUT:
 53		ret = da9055_reg_read(gpio->da9055, DA9055_REG_STATUS_B);
 54		if (ret < 0)
 55			return ret;
 56		break;
 57	case DA9055_OUTPUT:
 58		ret = da9055_reg_read(gpio->da9055, DA9055_REG_GPIO_MODE0_2);
 59		if (ret < 0)
 60			return ret;
 61	}
 62
 63	return ret & (1 << offset);
 64
 65}
 66
 67static void da9055_gpio_set(struct gpio_chip *gc, unsigned offset, int value)
 68{
 69	struct da9055_gpio *gpio = gpiochip_get_data(gc);
 70
 71	da9055_reg_update(gpio->da9055,
 72			DA9055_REG_GPIO_MODE0_2,
 73			1 << offset,
 74			value << offset);
 75}
 76
 77static int da9055_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
 78{
 79	struct da9055_gpio *gpio = gpiochip_get_data(gc);
 80	unsigned char reg_byte;
 81
 82	reg_byte = (DA9055_ACT_LOW | DA9055_GPI)
 83				<< DA9055_PORT_SHIFT(offset);
 84
 85	return da9055_reg_update(gpio->da9055, (offset >> 1) +
 86				DA9055_REG_GPIO0_1,
 87				DA9055_PORT_MASK <<
 88				DA9055_PORT_SHIFT(offset),
 89				reg_byte);
 90}
 91
 92static int da9055_gpio_direction_output(struct gpio_chip *gc,
 93					unsigned offset, int value)
 94{
 95	struct da9055_gpio *gpio = gpiochip_get_data(gc);
 96	unsigned char reg_byte;
 97	int ret;
 98
 99	reg_byte = (DA9055_VDD_IO | DA9055_PUSH_PULL)
100					<< DA9055_PORT_SHIFT(offset);
101
102	ret = da9055_reg_update(gpio->da9055, (offset >> 1) +
103				DA9055_REG_GPIO0_1,
104				DA9055_PORT_MASK <<
105				DA9055_PORT_SHIFT(offset),
106				reg_byte);
107	if (ret < 0)
108		return ret;
109
110	da9055_gpio_set(gc, offset, value);
111
112	return 0;
113}
114
115static int da9055_gpio_to_irq(struct gpio_chip *gc, u32 offset)
116{
117	struct da9055_gpio *gpio = gpiochip_get_data(gc);
118	struct da9055 *da9055 = gpio->da9055;
119
120	return regmap_irq_get_virq(da9055->irq_data,
121				  DA9055_IRQ_GPI0 + offset);
122}
123
124static const struct gpio_chip reference_gp = {
125	.label = "da9055-gpio",
126	.owner = THIS_MODULE,
127	.get = da9055_gpio_get,
128	.set = da9055_gpio_set,
129	.direction_input = da9055_gpio_direction_input,
130	.direction_output = da9055_gpio_direction_output,
131	.to_irq = da9055_gpio_to_irq,
132	.can_sleep = true,
133	.ngpio = 3,
134	.base = -1,
135};
136
137static int da9055_gpio_probe(struct platform_device *pdev)
138{
139	struct da9055_gpio *gpio;
140	struct da9055_pdata *pdata;
141	int ret;
142
143	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
144	if (!gpio)
145		return -ENOMEM;
146
147	gpio->da9055 = dev_get_drvdata(pdev->dev.parent);
148	pdata = dev_get_platdata(gpio->da9055->dev);
149
150	gpio->gp = reference_gp;
151	if (pdata && pdata->gpio_base)
152		gpio->gp.base = pdata->gpio_base;
153
154	ret = devm_gpiochip_add_data(&pdev->dev, &gpio->gp, gpio);
155	if (ret < 0) {
156		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
157		return ret;
158	}
159
160	platform_set_drvdata(pdev, gpio);
161
162	return 0;
163}
164
165static struct platform_driver da9055_gpio_driver = {
166	.probe = da9055_gpio_probe,
167	.driver = {
168		.name	= "da9055-gpio",
169	},
170};
171
172static int __init da9055_gpio_init(void)
173{
174	return platform_driver_register(&da9055_gpio_driver);
175}
176subsys_initcall(da9055_gpio_init);
177
178static void __exit da9055_gpio_exit(void)
179{
180	platform_driver_unregister(&da9055_gpio_driver);
181}
182module_exit(da9055_gpio_exit);
183
184MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
185MODULE_DESCRIPTION("DA9055 GPIO Device Driver");
186MODULE_LICENSE("GPL");
187MODULE_ALIAS("platform:da9055-gpio");