1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (c) 2011, NVIDIA Corporation. |
4 | */ |
5 | |
6 | #include <linux/init.h> |
7 | #include <linux/kernel.h> |
8 | #include <linux/module.h> |
9 | #include <linux/mod_devicetable.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 | |
18 | struct 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 | |
30 | static int rfkill_gpio_set_power(void *data, bool blocked) |
31 | { |
32 | struct rfkill_gpio_data *rfkill = data; |
33 | |
34 | if (!blocked && !IS_ERR(ptr: rfkill->clk) && !rfkill->clk_enabled) |
35 | clk_enable(clk: rfkill->clk); |
36 | |
37 | gpiod_set_value_cansleep(desc: rfkill->shutdown_gpio, value: !blocked); |
38 | gpiod_set_value_cansleep(desc: rfkill->reset_gpio, value: !blocked); |
39 | |
40 | if (blocked && !IS_ERR(ptr: rfkill->clk) && rfkill->clk_enabled) |
41 | clk_disable(clk: rfkill->clk); |
42 | |
43 | rfkill->clk_enabled = !blocked; |
44 | |
45 | return 0; |
46 | } |
47 | |
48 | static const struct rfkill_ops rfkill_gpio_ops = { |
49 | .set_block = rfkill_gpio_set_power, |
50 | }; |
51 | |
52 | static const struct acpi_gpio_params reset_gpios = { 0, 0, false }; |
53 | static const struct acpi_gpio_params shutdown_gpios = { 1, 0, false }; |
54 | |
55 | static const struct acpi_gpio_mapping acpi_rfkill_default_gpios[] = { |
56 | { "reset-gpios" , &reset_gpios, 1 }, |
57 | { "shutdown-gpios" , &shutdown_gpios, 1 }, |
58 | { }, |
59 | }; |
60 | |
61 | static int rfkill_gpio_acpi_probe(struct device *dev, |
62 | struct rfkill_gpio_data *rfkill) |
63 | { |
64 | const struct acpi_device_id *id; |
65 | |
66 | id = acpi_match_device(ids: dev->driver->acpi_match_table, dev); |
67 | if (!id) |
68 | return -ENODEV; |
69 | |
70 | rfkill->type = (unsigned)id->driver_data; |
71 | |
72 | return devm_acpi_dev_add_driver_gpios(dev, gpios: acpi_rfkill_default_gpios); |
73 | } |
74 | |
75 | static int rfkill_gpio_probe(struct platform_device *pdev) |
76 | { |
77 | struct rfkill_gpio_data *rfkill; |
78 | struct gpio_desc *gpio; |
79 | const char *name_property; |
80 | const char *type_property; |
81 | const char *type_name; |
82 | int ret; |
83 | |
84 | rfkill = devm_kzalloc(dev: &pdev->dev, size: sizeof(*rfkill), GFP_KERNEL); |
85 | if (!rfkill) |
86 | return -ENOMEM; |
87 | |
88 | if (dev_of_node(dev: &pdev->dev)) { |
89 | name_property = "label" ; |
90 | type_property = "radio-type" ; |
91 | } else { |
92 | name_property = "name" ; |
93 | type_property = "type" ; |
94 | } |
95 | device_property_read_string(dev: &pdev->dev, propname: name_property, val: &rfkill->name); |
96 | device_property_read_string(dev: &pdev->dev, propname: type_property, val: &type_name); |
97 | |
98 | if (!rfkill->name) |
99 | rfkill->name = dev_name(dev: &pdev->dev); |
100 | |
101 | rfkill->type = rfkill_find_type(name: type_name); |
102 | |
103 | if (ACPI_HANDLE(&pdev->dev)) { |
104 | ret = rfkill_gpio_acpi_probe(dev: &pdev->dev, rfkill); |
105 | if (ret) |
106 | return ret; |
107 | } |
108 | |
109 | rfkill->clk = devm_clk_get(dev: &pdev->dev, NULL); |
110 | |
111 | gpio = devm_gpiod_get_optional(dev: &pdev->dev, con_id: "reset" , flags: GPIOD_ASIS); |
112 | if (IS_ERR(ptr: gpio)) |
113 | return PTR_ERR(ptr: gpio); |
114 | |
115 | rfkill->reset_gpio = gpio; |
116 | |
117 | gpio = devm_gpiod_get_optional(dev: &pdev->dev, con_id: "shutdown" , flags: GPIOD_ASIS); |
118 | if (IS_ERR(ptr: gpio)) |
119 | return PTR_ERR(ptr: gpio); |
120 | |
121 | rfkill->shutdown_gpio = gpio; |
122 | |
123 | /* Make sure at-least one GPIO is defined for this instance */ |
124 | if (!rfkill->reset_gpio && !rfkill->shutdown_gpio) { |
125 | dev_err(&pdev->dev, "invalid platform data\n" ); |
126 | return -EINVAL; |
127 | } |
128 | |
129 | rfkill->rfkill_dev = rfkill_alloc(name: rfkill->name, parent: &pdev->dev, |
130 | type: rfkill->type, ops: &rfkill_gpio_ops, |
131 | ops_data: rfkill); |
132 | if (!rfkill->rfkill_dev) |
133 | return -ENOMEM; |
134 | |
135 | ret = rfkill_register(rfkill: rfkill->rfkill_dev); |
136 | if (ret < 0) |
137 | goto err_destroy; |
138 | |
139 | platform_set_drvdata(pdev, data: rfkill); |
140 | |
141 | dev_info(&pdev->dev, "%s device registered.\n" , rfkill->name); |
142 | |
143 | return 0; |
144 | |
145 | err_destroy: |
146 | rfkill_destroy(rfkill: rfkill->rfkill_dev); |
147 | |
148 | return ret; |
149 | } |
150 | |
151 | static int rfkill_gpio_remove(struct platform_device *pdev) |
152 | { |
153 | struct rfkill_gpio_data *rfkill = platform_get_drvdata(pdev); |
154 | |
155 | rfkill_unregister(rfkill: rfkill->rfkill_dev); |
156 | rfkill_destroy(rfkill: rfkill->rfkill_dev); |
157 | |
158 | return 0; |
159 | } |
160 | |
161 | #ifdef CONFIG_ACPI |
162 | static const struct acpi_device_id rfkill_acpi_match[] = { |
163 | { "BCM4752" , RFKILL_TYPE_GPS }, |
164 | { "LNV4752" , RFKILL_TYPE_GPS }, |
165 | { }, |
166 | }; |
167 | MODULE_DEVICE_TABLE(acpi, rfkill_acpi_match); |
168 | #endif |
169 | |
170 | static const struct of_device_id rfkill_of_match[] __maybe_unused = { |
171 | { .compatible = "rfkill-gpio" , }, |
172 | { }, |
173 | }; |
174 | MODULE_DEVICE_TABLE(of, rfkill_of_match); |
175 | |
176 | static struct platform_driver rfkill_gpio_driver = { |
177 | .probe = rfkill_gpio_probe, |
178 | .remove = rfkill_gpio_remove, |
179 | .driver = { |
180 | .name = "rfkill_gpio" , |
181 | .acpi_match_table = ACPI_PTR(rfkill_acpi_match), |
182 | .of_match_table = of_match_ptr(rfkill_of_match), |
183 | }, |
184 | }; |
185 | |
186 | module_platform_driver(rfkill_gpio_driver); |
187 | |
188 | MODULE_DESCRIPTION("gpio rfkill" ); |
189 | MODULE_AUTHOR("NVIDIA" ); |
190 | MODULE_LICENSE("GPL" ); |
191 | |