tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * TI TPS6586x GPIO driver
3 *
4 * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
5 * Author: Laxman dewangan <ldewangan@nvidia.com>
6 *
7 * Based on tps6586x.c
8 * Copyright (c) 2010 CompuLab Ltd.
9 * Mike Rapoport <mike@compulab.co.il>
10 *
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms and conditions of the GNU General Public License,
13 * version 2, as published by the Free Software Foundation.
14 *
15 * This program is distributed in the hope it will be useful, but WITHOUT
16 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
17 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
18 * more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program. If not, see <http://www.gnu.org/licenses/>.
22 */
23
24#include <linux/errno.h>
25#include <linux/gpio.h>
26#include <linux/kernel.h>
27#include <linux/module.h>
28#include <linux/mfd/tps6586x.h>
29#include <linux/of_device.h>
30#include <linux/platform_device.h>
31
32/* GPIO control registers */
33#define TPS6586X_GPIOSET1 0x5d
34#define TPS6586X_GPIOSET2 0x5e
35
36struct tps6586x_gpio {
37 struct gpio_chip gpio_chip;
38 struct device *parent;
39};
40
41static inline struct tps6586x_gpio *to_tps6586x_gpio(struct gpio_chip *chip)
42{
43 return container_of(chip, struct tps6586x_gpio, gpio_chip);
44}
45
46static int tps6586x_gpio_get(struct gpio_chip *gc, unsigned offset)
47{
48 struct tps6586x_gpio *tps6586x_gpio = to_tps6586x_gpio(gc);
49 uint8_t val;
50 int ret;
51
52 ret = tps6586x_read(tps6586x_gpio->parent, TPS6586X_GPIOSET2, &val);
53 if (ret)
54 return ret;
55
56 return !!(val & (1 << offset));
57}
58
59static void tps6586x_gpio_set(struct gpio_chip *gc, unsigned offset,
60 int value)
61{
62 struct tps6586x_gpio *tps6586x_gpio = to_tps6586x_gpio(gc);
63
64 tps6586x_update(tps6586x_gpio->parent, TPS6586X_GPIOSET2,
65 value << offset, 1 << offset);
66}
67
68static int tps6586x_gpio_output(struct gpio_chip *gc, unsigned offset,
69 int value)
70{
71 struct tps6586x_gpio *tps6586x_gpio = to_tps6586x_gpio(gc);
72 uint8_t val, mask;
73
74 tps6586x_gpio_set(gc, offset, value);
75
76 val = 0x1 << (offset * 2);
77 mask = 0x3 << (offset * 2);
78
79 return tps6586x_update(tps6586x_gpio->parent, TPS6586X_GPIOSET1,
80 val, mask);
81}
82
83static int __devinit tps6586x_gpio_probe(struct platform_device *pdev)
84{
85 struct tps6586x_platform_data *pdata;
86 struct tps6586x_gpio *tps6586x_gpio;
87 int ret;
88
89 pdata = dev_get_platdata(pdev->dev.parent);
90 tps6586x_gpio = devm_kzalloc(&pdev->dev,
91 sizeof(*tps6586x_gpio), GFP_KERNEL);
92 if (!tps6586x_gpio) {
93 dev_err(&pdev->dev, "Could not allocate tps6586x_gpio\n");
94 return -ENOMEM;
95 }
96
97 tps6586x_gpio->parent = pdev->dev.parent;
98
99 tps6586x_gpio->gpio_chip.owner = THIS_MODULE;
100 tps6586x_gpio->gpio_chip.label = pdev->name;
101 tps6586x_gpio->gpio_chip.dev = &pdev->dev;
102 tps6586x_gpio->gpio_chip.ngpio = 4;
103 tps6586x_gpio->gpio_chip.can_sleep = 1;
104
105 /* FIXME: add handling of GPIOs as dedicated inputs */
106 tps6586x_gpio->gpio_chip.direction_output = tps6586x_gpio_output;
107 tps6586x_gpio->gpio_chip.set = tps6586x_gpio_set;
108 tps6586x_gpio->gpio_chip.get = tps6586x_gpio_get;
109
110#ifdef CONFIG_OF_GPIO
111 tps6586x_gpio->gpio_chip.of_node = pdev->dev.parent->of_node;
112#endif
113 if (pdata && pdata->gpio_base)
114 tps6586x_gpio->gpio_chip.base = pdata->gpio_base;
115 else
116 tps6586x_gpio->gpio_chip.base = -1;
117
118 ret = gpiochip_add(&tps6586x_gpio->gpio_chip);
119 if (ret < 0) {
120 dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
121 return ret;
122 }
123
124 platform_set_drvdata(pdev, tps6586x_gpio);
125
126 return ret;
127}
128
129static int __devexit tps6586x_gpio_remove(struct platform_device *pdev)
130{
131 struct tps6586x_gpio *tps6586x_gpio = platform_get_drvdata(pdev);
132
133 return gpiochip_remove(&tps6586x_gpio->gpio_chip);
134}
135
136static struct platform_driver tps6586x_gpio_driver = {
137 .driver.name = "tps6586x-gpio",
138 .driver.owner = THIS_MODULE,
139 .probe = tps6586x_gpio_probe,
140 .remove = __devexit_p(tps6586x_gpio_remove),
141};
142
143static int __init tps6586x_gpio_init(void)
144{
145 return platform_driver_register(&tps6586x_gpio_driver);
146}
147subsys_initcall(tps6586x_gpio_init);
148
149static void __exit tps6586x_gpio_exit(void)
150{
151 platform_driver_unregister(&tps6586x_gpio_driver);
152}
153module_exit(tps6586x_gpio_exit);
154
155MODULE_ALIAS("platform:tps6586x-gpio");
156MODULE_DESCRIPTION("GPIO interface for TPS6586X PMIC");
157MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
158MODULE_LICENSE("GPL");