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220 lines · 5.2 KiB

1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (c) 2011, NVIDIA Corporation.
4 */
5
6#include <linux/dmi.h>
7#include <linux/init.h>
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/rfkill.h>
11#include <linux/of.h>
12#include <linux/platform_device.h>
13#include <linux/clk.h>
14#include <linux/slab.h>
15#include <linux/acpi.h>
16#include <linux/gpio/consumer.h>
17
18struct rfkill_gpio_data {
19 const char *name;
20 enum rfkill_type type;
21 struct gpio_desc *reset_gpio;
22 struct gpio_desc *shutdown_gpio;
23
24 struct rfkill *rfkill_dev;
25 struct clk *clk;
26
27 bool clk_enabled;
28};
29
30static int rfkill_gpio_set_power(void *data, bool blocked)
31{
32 struct rfkill_gpio_data *rfkill = data;
33
34 if (!blocked && !IS_ERR(rfkill->clk) && !rfkill->clk_enabled) {
35 int ret = clk_enable(rfkill->clk);
36
37 if (ret)
38 return ret;
39 }
40
41 gpiod_set_value_cansleep(rfkill->shutdown_gpio, !blocked);
42 gpiod_set_value_cansleep(rfkill->reset_gpio, !blocked);
43
44 if (blocked && !IS_ERR(rfkill->clk) && rfkill->clk_enabled)
45 clk_disable(rfkill->clk);
46
47 rfkill->clk_enabled = !blocked;
48
49 return 0;
50}
51
52static const struct rfkill_ops rfkill_gpio_ops = {
53 .set_block = rfkill_gpio_set_power,
54};
55
56static const struct acpi_gpio_params reset_gpios = { 0, 0, false };
57static const struct acpi_gpio_params shutdown_gpios = { 1, 0, false };
58
59static const struct acpi_gpio_mapping acpi_rfkill_default_gpios[] = {
60 { "reset-gpios", &reset_gpios, 1 },
61 { "shutdown-gpios", &shutdown_gpios, 1 },
62 { },
63};
64
65static int rfkill_gpio_acpi_probe(struct device *dev,
66 struct rfkill_gpio_data *rfkill)
67{
68 const struct acpi_device_id *id;
69
70 id = acpi_match_device(dev->driver->acpi_match_table, dev);
71 if (!id)
72 return -ENODEV;
73
74 rfkill->type = (unsigned)id->driver_data;
75
76 return devm_acpi_dev_add_driver_gpios(dev, acpi_rfkill_default_gpios);
77}
78
79/* List of DMI matches for devices on which rfkill-gpio should not load,
80 * to avoid firmware bugs.
81 */
82static const struct dmi_system_id rfkill_gpio_deny_table[] = {
83 {
84 /* Lenovo Yoga Tab 3 Pro YT3-X90, bogus "BCM4752" device in DSDT */
85 .matches = {
86 DMI_MATCH(DMI_SYS_VENDOR, "Intel Corporation"),
87 DMI_MATCH(DMI_PRODUCT_VERSION, "Blade3-10A-001"),
88 },
89 },
90 { }
91};
92
93static int rfkill_gpio_probe(struct platform_device *pdev)
94{
95 struct rfkill_gpio_data *rfkill;
96 const char *type_name = NULL;
97 const char *name_property;
98 const char *type_property;
99 struct gpio_desc *gpio;
100 int ret;
101
102 if (dmi_check_system(rfkill_gpio_deny_table))
103 return -ENODEV;
104
105 rfkill = devm_kzalloc(&pdev->dev, sizeof(*rfkill), GFP_KERNEL);
106 if (!rfkill)
107 return -ENOMEM;
108
109 if (dev_of_node(&pdev->dev)) {
110 name_property = "label";
111 type_property = "radio-type";
112 } else {
113 name_property = "name";
114 type_property = "type";
115 }
116 device_property_read_string(&pdev->dev, name_property, &rfkill->name);
117 device_property_read_string(&pdev->dev, type_property, &type_name);
118
119 if (!rfkill->name)
120 rfkill->name = dev_name(&pdev->dev);
121
122 rfkill->type = rfkill_find_type(type_name);
123
124 if (ACPI_HANDLE(&pdev->dev)) {
125 ret = rfkill_gpio_acpi_probe(&pdev->dev, rfkill);
126 if (ret)
127 return ret;
128 }
129
130 rfkill->clk = devm_clk_get(&pdev->dev, NULL);
131
132 gpio = devm_gpiod_get_optional(&pdev->dev, "reset", GPIOD_ASIS);
133 if (IS_ERR(gpio))
134 return PTR_ERR(gpio);
135
136 rfkill->reset_gpio = gpio;
137
138 gpio = devm_gpiod_get_optional(&pdev->dev, "shutdown", GPIOD_ASIS);
139 if (IS_ERR(gpio))
140 return PTR_ERR(gpio);
141
142 rfkill->shutdown_gpio = gpio;
143
144 /* Make sure at-least one GPIO is defined for this instance */
145 if (!rfkill->reset_gpio && !rfkill->shutdown_gpio) {
146 dev_err(&pdev->dev, "invalid platform data\n");
147 return -EINVAL;
148 }
149
150 ret = gpiod_direction_output(rfkill->reset_gpio, true);
151 if (ret)
152 return ret;
153
154 ret = gpiod_direction_output(rfkill->shutdown_gpio, true);
155 if (ret)
156 return ret;
157
158 rfkill->rfkill_dev = rfkill_alloc(rfkill->name, &pdev->dev,
159 rfkill->type, &rfkill_gpio_ops,
160 rfkill);
161 if (!rfkill->rfkill_dev)
162 return -ENOMEM;
163
164 if (device_property_present(&pdev->dev, "default-blocked"))
165 rfkill_init_sw_state(rfkill->rfkill_dev, true);
166
167 ret = rfkill_register(rfkill->rfkill_dev);
168 if (ret < 0)
169 goto err_destroy;
170
171 platform_set_drvdata(pdev, rfkill);
172
173 dev_info(&pdev->dev, "%s device registered.\n", rfkill->name);
174
175 return 0;
176
177err_destroy:
178 rfkill_destroy(rfkill->rfkill_dev);
179
180 return ret;
181}
182
183static void rfkill_gpio_remove(struct platform_device *pdev)
184{
185 struct rfkill_gpio_data *rfkill = platform_get_drvdata(pdev);
186
187 rfkill_unregister(rfkill->rfkill_dev);
188 rfkill_destroy(rfkill->rfkill_dev);
189}
190
191#ifdef CONFIG_ACPI
192static const struct acpi_device_id rfkill_acpi_match[] = {
193 { "BCM4752", RFKILL_TYPE_GPS },
194 { "LNV4752", RFKILL_TYPE_GPS },
195 { },
196};
197MODULE_DEVICE_TABLE(acpi, rfkill_acpi_match);
198#endif
199
200static const struct of_device_id rfkill_of_match[] __maybe_unused = {
201 { .compatible = "rfkill-gpio", },
202 { },
203};
204MODULE_DEVICE_TABLE(of, rfkill_of_match);
205
206static struct platform_driver rfkill_gpio_driver = {
207 .probe = rfkill_gpio_probe,
208 .remove = rfkill_gpio_remove,
209 .driver = {
210 .name = "rfkill_gpio",
211 .acpi_match_table = ACPI_PTR(rfkill_acpi_match),
212 .of_match_table = of_match_ptr(rfkill_of_match),
213 },
214};
215
216module_platform_driver(rfkill_gpio_driver);
217
218MODULE_DESCRIPTION("gpio rfkill");
219MODULE_AUTHOR("NVIDIA");
220MODULE_LICENSE("GPL");