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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/platform_device.h>
12#include <linux/clk.h>
13#include <linux/slab.h>
14#include <linux/acpi.h>
15#include <linux/gpio/consumer.h>
16
17struct rfkill_gpio_data {
18 const char *name;
19 enum rfkill_type type;
20 struct gpio_desc *reset_gpio;
21 struct gpio_desc *shutdown_gpio;
22
23 struct rfkill *rfkill_dev;
24 struct clk *clk;
25
26 bool clk_enabled;
27};
28
29static int rfkill_gpio_set_power(void *data, bool blocked)
30{
31 struct rfkill_gpio_data *rfkill = data;
32
33 if (!blocked && !IS_ERR(rfkill->clk) && !rfkill->clk_enabled)
34 clk_enable(rfkill->clk);
35
36 gpiod_set_value_cansleep(rfkill->shutdown_gpio, !blocked);
37 gpiod_set_value_cansleep(rfkill->reset_gpio, !blocked);
38
39 if (blocked && !IS_ERR(rfkill->clk) && rfkill->clk_enabled)
40 clk_disable(rfkill->clk);
41
42 rfkill->clk_enabled = !blocked;
43
44 return 0;
45}
46
47static const struct rfkill_ops rfkill_gpio_ops = {
48 .set_block = rfkill_gpio_set_power,
49};
50
51static const struct acpi_gpio_params reset_gpios = { 0, 0, false };
52static const struct acpi_gpio_params shutdown_gpios = { 1, 0, false };
53
54static const struct acpi_gpio_mapping acpi_rfkill_default_gpios[] = {
55 { "reset-gpios", &reset_gpios, 1 },
56 { "shutdown-gpios", &shutdown_gpios, 1 },
57 { },
58};
59
60static int rfkill_gpio_acpi_probe(struct device *dev,
61 struct rfkill_gpio_data *rfkill)
62{
63 const struct acpi_device_id *id;
64
65 id = acpi_match_device(dev->driver->acpi_match_table, dev);
66 if (!id)
67 return -ENODEV;
68
69 rfkill->type = (unsigned)id->driver_data;
70
71 return devm_acpi_dev_add_driver_gpios(dev, acpi_rfkill_default_gpios);
72}
73
74static int rfkill_gpio_probe(struct platform_device *pdev)
75{
76 struct rfkill_gpio_data *rfkill;
77 struct gpio_desc *gpio;
78 const char *type_name;
79 int ret;
80
81 rfkill = devm_kzalloc(&pdev->dev, sizeof(*rfkill), GFP_KERNEL);
82 if (!rfkill)
83 return -ENOMEM;
84
85 device_property_read_string(&pdev->dev, "name", &rfkill->name);
86 device_property_read_string(&pdev->dev, "type", &type_name);
87
88 if (!rfkill->name)
89 rfkill->name = dev_name(&pdev->dev);
90
91 rfkill->type = rfkill_find_type(type_name);
92
93 if (ACPI_HANDLE(&pdev->dev)) {
94 ret = rfkill_gpio_acpi_probe(&pdev->dev, rfkill);
95 if (ret)
96 return ret;
97 }
98
99 rfkill->clk = devm_clk_get(&pdev->dev, NULL);
100
101 gpio = devm_gpiod_get_optional(&pdev->dev, "reset", GPIOD_OUT_LOW);
102 if (IS_ERR(gpio))
103 return PTR_ERR(gpio);
104
105 rfkill->reset_gpio = gpio;
106
107 gpio = devm_gpiod_get_optional(&pdev->dev, "shutdown", GPIOD_OUT_LOW);
108 if (IS_ERR(gpio))
109 return PTR_ERR(gpio);
110
111 rfkill->shutdown_gpio = gpio;
112
113 /* Make sure at-least one GPIO is defined for this instance */
114 if (!rfkill->reset_gpio && !rfkill->shutdown_gpio) {
115 dev_err(&pdev->dev, "invalid platform data\n");
116 return -EINVAL;
117 }
118
119 rfkill->rfkill_dev = rfkill_alloc(rfkill->name, &pdev->dev,
120 rfkill->type, &rfkill_gpio_ops,
121 rfkill);
122 if (!rfkill->rfkill_dev)
123 return -ENOMEM;
124
125 ret = rfkill_register(rfkill->rfkill_dev);
126 if (ret < 0)
127 goto err_destroy;
128
129 platform_set_drvdata(pdev, rfkill);
130
131 dev_info(&pdev->dev, "%s device registered.\n", rfkill->name);
132
133 return 0;
134
135err_destroy:
136 rfkill_destroy(rfkill->rfkill_dev);
137
138 return ret;
139}
140
141static int rfkill_gpio_remove(struct platform_device *pdev)
142{
143 struct rfkill_gpio_data *rfkill = platform_get_drvdata(pdev);
144
145 rfkill_unregister(rfkill->rfkill_dev);
146 rfkill_destroy(rfkill->rfkill_dev);
147
148 return 0;
149}
150
151#ifdef CONFIG_ACPI
152static const struct acpi_device_id rfkill_acpi_match[] = {
153 { "BCM4752", RFKILL_TYPE_GPS },
154 { "LNV4752", RFKILL_TYPE_GPS },
155 { },
156};
157MODULE_DEVICE_TABLE(acpi, rfkill_acpi_match);
158#endif
159
160static struct platform_driver rfkill_gpio_driver = {
161 .probe = rfkill_gpio_probe,
162 .remove = rfkill_gpio_remove,
163 .driver = {
164 .name = "rfkill_gpio",
165 .acpi_match_table = ACPI_PTR(rfkill_acpi_match),
166 },
167};
168
169module_platform_driver(rfkill_gpio_driver);
170
171MODULE_DESCRIPTION("gpio rfkill");
172MODULE_AUTHOR("NVIDIA");
173MODULE_LICENSE("GPL");
1/*
2 * Copyright (c) 2011, NVIDIA Corporation.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
17 */
18
19#include <linux/gpio.h>
20#include <linux/init.h>
21#include <linux/kernel.h>
22#include <linux/module.h>
23#include <linux/rfkill.h>
24#include <linux/platform_device.h>
25#include <linux/clk.h>
26#include <linux/slab.h>
27
28#include <linux/rfkill-gpio.h>
29
30enum rfkill_gpio_clk_state {
31 UNSPECIFIED = 0,
32 PWR_ENABLED,
33 PWR_DISABLED
34};
35
36#define PWR_CLK_SET(_RF, _EN) \
37 ((_RF)->pwr_clk_enabled = (!(_EN) ? PWR_ENABLED : PWR_DISABLED))
38#define PWR_CLK_ENABLED(_RF) ((_RF)->pwr_clk_enabled == PWR_ENABLED)
39#define PWR_CLK_DISABLED(_RF) ((_RF)->pwr_clk_enabled != PWR_ENABLED)
40
41struct rfkill_gpio_data {
42 struct rfkill_gpio_platform_data *pdata;
43 struct rfkill *rfkill_dev;
44 char *reset_name;
45 char *shutdown_name;
46 enum rfkill_gpio_clk_state pwr_clk_enabled;
47 struct clk *pwr_clk;
48};
49
50static int rfkill_gpio_set_power(void *data, bool blocked)
51{
52 struct rfkill_gpio_data *rfkill = data;
53
54 if (blocked) {
55 if (gpio_is_valid(rfkill->pdata->shutdown_gpio))
56 gpio_direction_output(rfkill->pdata->shutdown_gpio, 0);
57 if (gpio_is_valid(rfkill->pdata->reset_gpio))
58 gpio_direction_output(rfkill->pdata->reset_gpio, 0);
59 if (rfkill->pwr_clk && PWR_CLK_ENABLED(rfkill))
60 clk_disable(rfkill->pwr_clk);
61 } else {
62 if (rfkill->pwr_clk && PWR_CLK_DISABLED(rfkill))
63 clk_enable(rfkill->pwr_clk);
64 if (gpio_is_valid(rfkill->pdata->reset_gpio))
65 gpio_direction_output(rfkill->pdata->reset_gpio, 1);
66 if (gpio_is_valid(rfkill->pdata->shutdown_gpio))
67 gpio_direction_output(rfkill->pdata->shutdown_gpio, 1);
68 }
69
70 if (rfkill->pwr_clk)
71 PWR_CLK_SET(rfkill, blocked);
72
73 return 0;
74}
75
76static const struct rfkill_ops rfkill_gpio_ops = {
77 .set_block = rfkill_gpio_set_power,
78};
79
80static int rfkill_gpio_probe(struct platform_device *pdev)
81{
82 struct rfkill_gpio_data *rfkill;
83 struct rfkill_gpio_platform_data *pdata = pdev->dev.platform_data;
84 int ret = 0;
85 int len = 0;
86
87 if (!pdata) {
88 pr_warn("%s: No platform data specified\n", __func__);
89 return -EINVAL;
90 }
91
92 /* make sure at-least one of the GPIO is defined and that
93 * a name is specified for this instance */
94 if (!pdata->name || (!gpio_is_valid(pdata->reset_gpio) &&
95 !gpio_is_valid(pdata->shutdown_gpio))) {
96 pr_warn("%s: invalid platform data\n", __func__);
97 return -EINVAL;
98 }
99
100 rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
101 if (!rfkill)
102 return -ENOMEM;
103
104 rfkill->pdata = pdata;
105
106 len = strlen(pdata->name);
107 rfkill->reset_name = kzalloc(len + 7, GFP_KERNEL);
108 if (!rfkill->reset_name) {
109 ret = -ENOMEM;
110 goto fail_alloc;
111 }
112
113 rfkill->shutdown_name = kzalloc(len + 10, GFP_KERNEL);
114 if (!rfkill->shutdown_name) {
115 ret = -ENOMEM;
116 goto fail_reset_name;
117 }
118
119 snprintf(rfkill->reset_name, len + 6 , "%s_reset", pdata->name);
120 snprintf(rfkill->shutdown_name, len + 9, "%s_shutdown", pdata->name);
121
122 if (pdata->power_clk_name) {
123 rfkill->pwr_clk = clk_get(&pdev->dev, pdata->power_clk_name);
124 if (IS_ERR(rfkill->pwr_clk)) {
125 pr_warn("%s: can't find pwr_clk.\n", __func__);
126 goto fail_shutdown_name;
127 }
128 }
129
130 if (gpio_is_valid(pdata->reset_gpio)) {
131 ret = gpio_request(pdata->reset_gpio, rfkill->reset_name);
132 if (ret) {
133 pr_warn("%s: failed to get reset gpio.\n", __func__);
134 goto fail_clock;
135 }
136 }
137
138 if (gpio_is_valid(pdata->shutdown_gpio)) {
139 ret = gpio_request(pdata->shutdown_gpio, rfkill->shutdown_name);
140 if (ret) {
141 pr_warn("%s: failed to get shutdown gpio.\n", __func__);
142 goto fail_reset;
143 }
144 }
145
146 rfkill->rfkill_dev = rfkill_alloc(pdata->name, &pdev->dev, pdata->type,
147 &rfkill_gpio_ops, rfkill);
148 if (!rfkill->rfkill_dev)
149 goto fail_shutdown;
150
151 ret = rfkill_register(rfkill->rfkill_dev);
152 if (ret < 0)
153 goto fail_rfkill;
154
155 platform_set_drvdata(pdev, rfkill);
156
157 dev_info(&pdev->dev, "%s device registered.\n", pdata->name);
158
159 return 0;
160
161fail_rfkill:
162 rfkill_destroy(rfkill->rfkill_dev);
163fail_shutdown:
164 if (gpio_is_valid(pdata->shutdown_gpio))
165 gpio_free(pdata->shutdown_gpio);
166fail_reset:
167 if (gpio_is_valid(pdata->reset_gpio))
168 gpio_free(pdata->reset_gpio);
169fail_clock:
170 if (rfkill->pwr_clk)
171 clk_put(rfkill->pwr_clk);
172fail_shutdown_name:
173 kfree(rfkill->shutdown_name);
174fail_reset_name:
175 kfree(rfkill->reset_name);
176fail_alloc:
177 kfree(rfkill);
178
179 return ret;
180}
181
182static int rfkill_gpio_remove(struct platform_device *pdev)
183{
184 struct rfkill_gpio_data *rfkill = platform_get_drvdata(pdev);
185
186 rfkill_unregister(rfkill->rfkill_dev);
187 rfkill_destroy(rfkill->rfkill_dev);
188 if (gpio_is_valid(rfkill->pdata->shutdown_gpio))
189 gpio_free(rfkill->pdata->shutdown_gpio);
190 if (gpio_is_valid(rfkill->pdata->reset_gpio))
191 gpio_free(rfkill->pdata->reset_gpio);
192 if (rfkill->pwr_clk && PWR_CLK_ENABLED(rfkill))
193 clk_disable(rfkill->pwr_clk);
194 if (rfkill->pwr_clk)
195 clk_put(rfkill->pwr_clk);
196 kfree(rfkill->shutdown_name);
197 kfree(rfkill->reset_name);
198 kfree(rfkill);
199
200 return 0;
201}
202
203static struct platform_driver rfkill_gpio_driver = {
204 .probe = rfkill_gpio_probe,
205 .remove = __devexit_p(rfkill_gpio_remove),
206 .driver = {
207 .name = "rfkill_gpio",
208 .owner = THIS_MODULE,
209 },
210};
211
212static int __init rfkill_gpio_init(void)
213{
214 return platform_driver_register(&rfkill_gpio_driver);
215}
216
217static void __exit rfkill_gpio_exit(void)
218{
219 platform_driver_unregister(&rfkill_gpio_driver);
220}
221
222module_init(rfkill_gpio_init);
223module_exit(rfkill_gpio_exit);
224
225MODULE_DESCRIPTION("gpio rfkill");
226MODULE_AUTHOR("NVIDIA");
227MODULE_LICENSE("GPL");