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