tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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 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");