aboutsummaryrefslogtreecommitdiff
path: root/drivers/gpio/gpio-altera-a10sr.c
blob: 16a8951b2beda389368c858848beb2edaf06949f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
/*
 *  Copyright Intel Corporation (C) 2014-2016. All Rights Reserved
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * GPIO driver for  Altera Arria10 MAX5 System Resource Chip
 *
 * Adapted from gpio-tps65910.c
 */

#include <linux/gpio/driver.h>
#include <linux/mfd/altera-a10sr.h>
#include <linux/module.h>

/**
 * struct altr_a10sr_gpio - Altera Max5 GPIO device private data structure
 * @gp:   : instance of the gpio_chip
 * @regmap: the regmap from the parent device.
 */
struct altr_a10sr_gpio {
	struct gpio_chip gp;
	struct regmap *regmap;
};

static int altr_a10sr_gpio_get(struct gpio_chip *chip, unsigned int offset)
{
	struct altr_a10sr_gpio *gpio = gpiochip_get_data(chip);
	int ret, val;

	ret = regmap_read(gpio->regmap, ALTR_A10SR_PBDSW_REG, &val);
	if (ret < 0)
		return ret;

	return !!(val & BIT(offset - ALTR_A10SR_LED_VALID_SHIFT));
}

static void altr_a10sr_gpio_set(struct gpio_chip *chip, unsigned int offset,
				int value)
{
	struct altr_a10sr_gpio *gpio = gpiochip_get_data(chip);

	regmap_update_bits(gpio->regmap, ALTR_A10SR_LED_REG,
			   BIT(ALTR_A10SR_LED_VALID_SHIFT + offset),
			   value ? BIT(ALTR_A10SR_LED_VALID_SHIFT + offset)
			   : 0);
}

static int altr_a10sr_gpio_direction_input(struct gpio_chip *gc,
					   unsigned int nr)
{
	if (nr >= (ALTR_A10SR_IN_VALID_RANGE_LO - ALTR_A10SR_LED_VALID_SHIFT))
		return 0;
	return -EINVAL;
}

static int altr_a10sr_gpio_direction_output(struct gpio_chip *gc,
					    unsigned int nr, int value)
{
	if (nr <= (ALTR_A10SR_OUT_VALID_RANGE_HI - ALTR_A10SR_LED_VALID_SHIFT))
		return 0;
	return -EINVAL;
}

static struct gpio_chip altr_a10sr_gc = {
	.label = "altr_a10sr_gpio",
	.owner = THIS_MODULE,
	.get = altr_a10sr_gpio_get,
	.set = altr_a10sr_gpio_set,
	.direction_input = altr_a10sr_gpio_direction_input,
	.direction_output = altr_a10sr_gpio_direction_output,
	.can_sleep = true,
	.ngpio = 12,
	.base = -1,
};

static int altr_a10sr_gpio_probe(struct platform_device *pdev)
{
	struct altr_a10sr_gpio *gpio;
	int ret;
	struct altr_a10sr *a10sr = dev_get_drvdata(pdev->dev.parent);

	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
	if (!gpio)
		return -ENOMEM;

	gpio->regmap = a10sr->regmap;

	gpio->gp = altr_a10sr_gc;
	gpio->gp.parent = pdev->dev.parent;
	gpio->gp.of_node = pdev->dev.of_node;

	ret = devm_gpiochip_add_data(&pdev->dev, &gpio->gp, gpio);
	if (ret < 0) {
		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
		return ret;
	}

	platform_set_drvdata(pdev, gpio);

	return 0;
}

static const struct of_device_id altr_a10sr_gpio_of_match[] = {
	{ .compatible = "altr,a10sr-gpio" },
	{ },
};
MODULE_DEVICE_TABLE(of, altr_a10sr_gpio_of_match);

static struct platform_driver altr_a10sr_gpio_driver = {
	.probe = altr_a10sr_gpio_probe,
	.driver = {
		.name	= "altr_a10sr_gpio",
		.of_match_table = of_match_ptr(altr_a10sr_gpio_of_match),
	},
};
module_platform_driver(altr_a10sr_gpio_driver);

MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Thor Thayer <tthayer@opensource.altera.com>");
MODULE_DESCRIPTION("Altera Arria10 System Resource Chip GPIO");