summaryrefslogtreecommitdiffstats
path: root/net/rfkill/rfkill-gpio.c
blob: 5a81505fba9ac4091ad5ac968018979d50876c86 (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
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (c) 2011, NVIDIA Corporation.
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/rfkill.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/slab.h>
#include <linux/acpi.h>
#include <linux/gpio/consumer.h>

struct rfkill_gpio_data {
	const char		*name;
	enum rfkill_type	type;
	struct gpio_desc	*reset_gpio;
	struct gpio_desc	*shutdown_gpio;

	struct rfkill		*rfkill_dev;
	struct clk		*clk;

	bool			clk_enabled;
};

static int rfkill_gpio_set_power(void *data, bool blocked)
{
	struct rfkill_gpio_data *rfkill = data;

	if (!blocked && !IS_ERR(rfkill->clk) && !rfkill->clk_enabled)
		clk_enable(rfkill->clk);

	gpiod_set_value_cansleep(rfkill->shutdown_gpio, !blocked);
	gpiod_set_value_cansleep(rfkill->reset_gpio, !blocked);

	if (blocked && !IS_ERR(rfkill->clk) && rfkill->clk_enabled)
		clk_disable(rfkill->clk);

	rfkill->clk_enabled = !blocked;

	return 0;
}

static const struct rfkill_ops rfkill_gpio_ops = {
	.set_block = rfkill_gpio_set_power,
};

static const struct acpi_gpio_params reset_gpios = { 0, 0, false };
static const struct acpi_gpio_params shutdown_gpios = { 1, 0, false };

static const struct acpi_gpio_mapping acpi_rfkill_default_gpios[] = {
	{ "reset-gpios", &reset_gpios, 1 },
	{ "shutdown-gpios", &shutdown_gpios, 1 },
	{ },
};

static int rfkill_gpio_acpi_probe(struct device *dev,
				  struct rfkill_gpio_data *rfkill)
{
	const struct acpi_device_id *id;

	id = acpi_match_device(dev->driver->acpi_match_table, dev);
	if (!id)
		return -ENODEV;

	rfkill->type = (unsigned)id->driver_data;

	return devm_acpi_dev_add_driver_gpios(dev, acpi_rfkill_default_gpios);
}

static int rfkill_gpio_probe(struct platform_device *pdev)
{
	struct rfkill_gpio_data *rfkill;
	struct gpio_desc *gpio;
	const char *name_property;
	const char *type_property;
	const char *type_name;
	int ret;

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

	if (dev_of_node(&pdev->dev)) {
		name_property = "label";
		type_property = "radio-type";
	} else {
		name_property = "name";
		type_property = "type";
	}
	device_property_read_string(&pdev->dev, name_property, &rfkill->name);
	device_property_read_string(&pdev->dev, type_property, &type_name);

	if (!rfkill->name)
		rfkill->name = dev_name(&pdev->dev);

	rfkill->type = rfkill_find_type(type_name);

	if (ACPI_HANDLE(&pdev->dev)) {
		ret = rfkill_gpio_acpi_probe(&pdev->dev, rfkill);
		if (ret)
			return ret;
	}

	rfkill->clk = devm_clk_get(&pdev->dev, NULL);

	gpio = devm_gpiod_get_optional(&pdev->dev, "reset", GPIOD_ASIS);
	if (IS_ERR(gpio))
		return PTR_ERR(gpio);

	rfkill->reset_gpio = gpio;

	gpio = devm_gpiod_get_optional(&pdev->dev, "shutdown", GPIOD_ASIS);
	if (IS_ERR(gpio))
		return PTR_ERR(gpio);

	rfkill->shutdown_gpio = gpio;

	/* Make sure at-least one GPIO is defined for this instance */
	if (!rfkill->reset_gpio && !rfkill->shutdown_gpio) {
		dev_err(&pdev->dev, "invalid platform data\n");
		return -EINVAL;
	}

	rfkill->rfkill_dev = rfkill_alloc(rfkill->name, &pdev->dev,
					  rfkill->type, &rfkill_gpio_ops,
					  rfkill);
	if (!rfkill->rfkill_dev)
		return -ENOMEM;

	ret = rfkill_register(rfkill->rfkill_dev);
	if (ret < 0)
		goto err_destroy;

	platform_set_drvdata(pdev, rfkill);

	dev_info(&pdev->dev, "%s device registered.\n", rfkill->name);

	return 0;

err_destroy:
	rfkill_destroy(rfkill->rfkill_dev);

	return ret;
}

static int rfkill_gpio_remove(struct platform_device *pdev)
{
	struct rfkill_gpio_data *rfkill = platform_get_drvdata(pdev);

	rfkill_unregister(rfkill->rfkill_dev);
	rfkill_destroy(rfkill->rfkill_dev);

	return 0;
}

#ifdef CONFIG_ACPI
static const struct acpi_device_id rfkill_acpi_match[] = {
	{ "BCM4752", RFKILL_TYPE_GPS },
	{ "LNV4752", RFKILL_TYPE_GPS },
	{ },
};
MODULE_DEVICE_TABLE(acpi, rfkill_acpi_match);
#endif

static const struct of_device_id rfkill_of_match[] __maybe_unused = {
	{ .compatible = "rfkill-gpio", },
	{ },
};
MODULE_DEVICE_TABLE(of, rfkill_of_match);

static struct platform_driver rfkill_gpio_driver = {
	.probe = rfkill_gpio_probe,
	.remove = rfkill_gpio_remove,
	.driver = {
		.name = "rfkill_gpio",
		.acpi_match_table = ACPI_PTR(rfkill_acpi_match),
		.of_match_table = of_match_ptr(rfkill_of_match),
	},
};

module_platform_driver(rfkill_gpio_driver);

MODULE_DESCRIPTION("gpio rfkill");
MODULE_AUTHOR("NVIDIA");
MODULE_LICENSE("GPL");