xref: /openbmc/linux/drivers/gpio/gpio-da9055.c (revision 6d99a79c)
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/driver.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 
33 struct da9055_gpio {
34 	struct da9055 *da9055;
35 	struct gpio_chip gp;
36 };
37 
38 static 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 
67 static 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 
77 static 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 
92 static 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 
115 static 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 
124 static 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 
137 static 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 
165 static struct platform_driver da9055_gpio_driver = {
166 	.probe = da9055_gpio_probe,
167 	.driver = {
168 		.name	= "da9055-gpio",
169 	},
170 };
171 
172 static int __init da9055_gpio_init(void)
173 {
174 	return platform_driver_register(&da9055_gpio_driver);
175 }
176 subsys_initcall(da9055_gpio_init);
177 
178 static void __exit da9055_gpio_exit(void)
179 {
180 	platform_driver_unregister(&da9055_gpio_driver);
181 }
182 module_exit(da9055_gpio_exit);
183 
184 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
185 MODULE_DESCRIPTION("DA9055 GPIO Device Driver");
186 MODULE_LICENSE("GPL");
187 MODULE_ALIAS("platform:da9055-gpio");
188