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
16#include <linux/gpio.h>
17
18struct adp5520_gpio {
19	struct device *master;
20	struct gpio_chip gpio_chip;
21	unsigned char lut[ADP5520_MAXGPIOS];
22	unsigned long output;
23};
24
25static int adp5520_gpio_get_value(struct gpio_chip *chip, unsigned off)
26{
27	struct adp5520_gpio *dev;
28	uint8_t reg_val;
29
30	dev = container_of(chip, struct adp5520_gpio, gpio_chip);
31
32	/*
33	 * There are dedicated registers for GPIO IN/OUT.
34	 * Make sure we return the right value, even when configured as output
35	 */
36
37	if (test_bit(off, &dev->output))
38		adp5520_read(dev->master, ADP5520_GPIO_OUT, &reg_val);
39	else
40		adp5520_read(dev->master, ADP5520_GPIO_IN, &reg_val);
41
42	return !!(reg_val & dev->lut[off]);
43}
44
45static void adp5520_gpio_set_value(struct gpio_chip *chip,
46		unsigned off, int val)
47{
48	struct adp5520_gpio *dev;
49	dev = container_of(chip, struct adp5520_gpio, gpio_chip);
50
51	if (val)
52		adp5520_set_bits(dev->master, ADP5520_GPIO_OUT, dev->lut[off]);
53	else
54		adp5520_clr_bits(dev->master, ADP5520_GPIO_OUT, dev->lut[off]);
55}
56
57static int adp5520_gpio_direction_input(struct gpio_chip *chip, unsigned off)
58{
59	struct adp5520_gpio *dev;
60	dev = container_of(chip, struct adp5520_gpio, gpio_chip);
61
62	clear_bit(off, &dev->output);
63
64	return adp5520_clr_bits(dev->master, ADP5520_GPIO_CFG_2,
65				dev->lut[off]);
66}
67
68static int adp5520_gpio_direction_output(struct gpio_chip *chip,
69		unsigned off, int val)
70{
71	struct adp5520_gpio *dev;
72	int ret = 0;
73	dev = container_of(chip, struct adp5520_gpio, gpio_chip);
74
75	set_bit(off, &dev->output);
76
77	if (val)
78		ret |= adp5520_set_bits(dev->master, ADP5520_GPIO_OUT,
79					dev->lut[off]);
80	else
81		ret |= adp5520_clr_bits(dev->master, ADP5520_GPIO_OUT,
82					dev->lut[off]);
83
84	ret |= adp5520_set_bits(dev->master, ADP5520_GPIO_CFG_2,
85					dev->lut[off]);
86
87	return ret;
88}
89
90static int adp5520_gpio_probe(struct platform_device *pdev)
91{
92	struct adp5520_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
93	struct adp5520_gpio *dev;
94	struct gpio_chip *gc;
95	int ret, i, gpios;
96	unsigned char ctl_mask = 0;
97
98	if (pdata == NULL) {
99		dev_err(&pdev->dev, "missing platform data\n");
100		return -ENODEV;
101	}
102
103	if (pdev->id != ID_ADP5520) {
104		dev_err(&pdev->dev, "only ADP5520 supports GPIO\n");
105		return -ENODEV;
106	}
107
108	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
109	if (dev == NULL)
110		return -ENOMEM;
111
112	dev->master = pdev->dev.parent;
113
114	for (gpios = 0, i = 0; i < ADP5520_MAXGPIOS; i++)
115		if (pdata->gpio_en_mask & (1 << i))
116			dev->lut[gpios++] = 1 << i;
117
118	if (gpios < 1) {
119		ret = -EINVAL;
120		goto err;
121	}
122
123	gc = &dev->gpio_chip;
124	gc->direction_input  = adp5520_gpio_direction_input;
125	gc->direction_output = adp5520_gpio_direction_output;
126	gc->get = adp5520_gpio_get_value;
127	gc->set = adp5520_gpio_set_value;
128	gc->can_sleep = true;
129
130	gc->base = pdata->gpio_start;
131	gc->ngpio = gpios;
132	gc->label = pdev->name;
133	gc->owner = THIS_MODULE;
134
135	ret = adp5520_clr_bits(dev->master, ADP5520_GPIO_CFG_1,
136		pdata->gpio_en_mask);
137
138	if (pdata->gpio_en_mask & ADP5520_GPIO_C3)
139		ctl_mask |= ADP5520_C3_MODE;
140
141	if (pdata->gpio_en_mask & ADP5520_GPIO_R3)
142		ctl_mask |= ADP5520_R3_MODE;
143
144	if (ctl_mask)
145		ret = adp5520_set_bits(dev->master, ADP5520_LED_CONTROL,
146			ctl_mask);
147
148	ret |= adp5520_set_bits(dev->master, ADP5520_GPIO_PULLUP,
149		pdata->gpio_pullup_mask);
150
151	if (ret) {
152		dev_err(&pdev->dev, "failed to write\n");
153		goto err;
154	}
155
156	ret = gpiochip_add(&dev->gpio_chip);
157	if (ret)
158		goto err;
159
160	platform_set_drvdata(pdev, dev);
161	return 0;
162
163err:
164	return ret;
165}
166
167static int adp5520_gpio_remove(struct platform_device *pdev)
168{
169	struct adp5520_gpio *dev;
170
171	dev = platform_get_drvdata(pdev);
172	gpiochip_remove(&dev->gpio_chip);
173
174	return 0;
175}
176
177static struct platform_driver adp5520_gpio_driver = {
178	.driver	= {
179		.name	= "adp5520-gpio",
180	},
181	.probe		= adp5520_gpio_probe,
182	.remove		= adp5520_gpio_remove,
183};
184
185module_platform_driver(adp5520_gpio_driver);
186
187MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
188MODULE_DESCRIPTION("GPIO ADP5520 Driver");
189MODULE_LICENSE("GPL");
190MODULE_ALIAS("platform:adp5520-gpio");
191