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 Analog Devices ADP5520 MFD PMICs
3 *
4 * Copyright 2009 Analog Devices Inc.
5 *
6 * Licensed under the GPL-2 or later.
7 */
8
9#include <linux/module.h>
10#include <linux/slab.h>
11#include <linux/kernel.h>
12#include <linux/init.h>
13#include <linux/platform_device.h>
14#include <linux/mfd/adp5520.h>
15#include <linux/gpio/driver.h>
16
17struct adp5520_gpio {
18 struct device *master;
19 struct gpio_chip gpio_chip;
20 unsigned char lut[ADP5520_MAXGPIOS];
21 unsigned long output;
22};
23
24static int adp5520_gpio_get_value(struct gpio_chip *chip, unsigned off)
25{
26 struct adp5520_gpio *dev;
27 uint8_t reg_val;
28
29 dev = gpiochip_get_data(chip);
30
31 /*
32 * There are dedicated registers for GPIO IN/OUT.
33 * Make sure we return the right value, even when configured as output
34 */
35
36 if (test_bit(off, &dev->output))
37 adp5520_read(dev->master, ADP5520_GPIO_OUT, ®_val);
38 else
39 adp5520_read(dev->master, ADP5520_GPIO_IN, ®_val);
40
41 return !!(reg_val & dev->lut[off]);
42}
43
44static void adp5520_gpio_set_value(struct gpio_chip *chip,
45 unsigned off, int val)
46{
47 struct adp5520_gpio *dev;
48 dev = gpiochip_get_data(chip);
49
50 if (val)
51 adp5520_set_bits(dev->master, ADP5520_GPIO_OUT, dev->lut[off]);
52 else
53 adp5520_clr_bits(dev->master, ADP5520_GPIO_OUT, dev->lut[off]);
54}
55
56static int adp5520_gpio_direction_input(struct gpio_chip *chip, unsigned off)
57{
58 struct adp5520_gpio *dev;
59 dev = gpiochip_get_data(chip);
60
61 clear_bit(off, &dev->output);
62
63 return adp5520_clr_bits(dev->master, ADP5520_GPIO_CFG_2,
64 dev->lut[off]);
65}
66
67static int adp5520_gpio_direction_output(struct gpio_chip *chip,
68 unsigned off, int val)
69{
70 struct adp5520_gpio *dev;
71 int ret = 0;
72 dev = gpiochip_get_data(chip);
73
74 set_bit(off, &dev->output);
75
76 if (val)
77 ret |= adp5520_set_bits(dev->master, ADP5520_GPIO_OUT,
78 dev->lut[off]);
79 else
80 ret |= adp5520_clr_bits(dev->master, ADP5520_GPIO_OUT,
81 dev->lut[off]);
82
83 ret |= adp5520_set_bits(dev->master, ADP5520_GPIO_CFG_2,
84 dev->lut[off]);
85
86 return ret;
87}
88
89static int adp5520_gpio_probe(struct platform_device *pdev)
90{
91 struct adp5520_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
92 struct adp5520_gpio *dev;
93 struct gpio_chip *gc;
94 int ret, i, gpios;
95 unsigned char ctl_mask = 0;
96
97 if (pdata == NULL) {
98 dev_err(&pdev->dev, "missing platform data\n");
99 return -ENODEV;
100 }
101
102 if (pdev->id != ID_ADP5520) {
103 dev_err(&pdev->dev, "only ADP5520 supports GPIO\n");
104 return -ENODEV;
105 }
106
107 dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
108 if (dev == NULL)
109 return -ENOMEM;
110
111 dev->master = pdev->dev.parent;
112
113 for (gpios = 0, i = 0; i < ADP5520_MAXGPIOS; i++)
114 if (pdata->gpio_en_mask & (1 << i))
115 dev->lut[gpios++] = 1 << i;
116
117 if (gpios < 1) {
118 ret = -EINVAL;
119 goto err;
120 }
121
122 gc = &dev->gpio_chip;
123 gc->direction_input = adp5520_gpio_direction_input;
124 gc->direction_output = adp5520_gpio_direction_output;
125 gc->get = adp5520_gpio_get_value;
126 gc->set = adp5520_gpio_set_value;
127 gc->can_sleep = true;
128
129 gc->base = pdata->gpio_start;
130 gc->ngpio = gpios;
131 gc->label = pdev->name;
132 gc->owner = THIS_MODULE;
133
134 ret = adp5520_clr_bits(dev->master, ADP5520_GPIO_CFG_1,
135 pdata->gpio_en_mask);
136
137 if (pdata->gpio_en_mask & ADP5520_GPIO_C3)
138 ctl_mask |= ADP5520_C3_MODE;
139
140 if (pdata->gpio_en_mask & ADP5520_GPIO_R3)
141 ctl_mask |= ADP5520_R3_MODE;
142
143 if (ctl_mask)
144 ret = adp5520_set_bits(dev->master, ADP5520_LED_CONTROL,
145 ctl_mask);
146
147 ret |= adp5520_set_bits(dev->master, ADP5520_GPIO_PULLUP,
148 pdata->gpio_pullup_mask);
149
150 if (ret) {
151 dev_err(&pdev->dev, "failed to write\n");
152 goto err;
153 }
154
155 ret = devm_gpiochip_add_data(&pdev->dev, &dev->gpio_chip, dev);
156 if (ret)
157 goto err;
158
159 platform_set_drvdata(pdev, dev);
160 return 0;
161
162err:
163 return ret;
164}
165
166static struct platform_driver adp5520_gpio_driver = {
167 .driver = {
168 .name = "adp5520-gpio",
169 },
170 .probe = adp5520_gpio_probe,
171};
172
173module_platform_driver(adp5520_gpio_driver);
174
175MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
176MODULE_DESCRIPTION("GPIO ADP5520 Driver");
177MODULE_LICENSE("GPL");
178MODULE_ALIAS("platform:adp5520-gpio");