xref: /openbmc/linux/drivers/gpio/gpio-da9055.c (revision b6bec26c)
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 
33 struct da9055_gpio {
34 	struct da9055 *da9055;
35 	struct gpio_chip gp;
36 };
37 
38 static inline struct da9055_gpio *to_da9055_gpio(struct gpio_chip *chip)
39 {
40 	return container_of(chip, struct da9055_gpio, gp);
41 }
42 
43 static 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 
72 static 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 
82 static 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 
97 static 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 
120 static 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 
129 static 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 = 1,
138 	.ngpio = 3,
139 	.base = -1,
140 };
141 
142 static 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 = gpio->da9055->dev->platform_data;
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 
169 err_mem:
170 	return ret;
171 }
172 
173 static 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 
180 static 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 
189 static int __init da9055_gpio_init(void)
190 {
191 	return platform_driver_register(&da9055_gpio_driver);
192 }
193 subsys_initcall(da9055_gpio_init);
194 
195 static void __exit da9055_gpio_exit(void)
196 {
197 	platform_driver_unregister(&da9055_gpio_driver);
198 }
199 module_exit(da9055_gpio_exit);
200 
201 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
202 MODULE_DESCRIPTION("DA9055 GPIO Device Driver");
203 MODULE_LICENSE("GPL");
204 MODULE_ALIAS("platform:da9055-gpio");
205