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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * drivers/extcon/extcon-usb-gpio.c - USB GPIO extcon driver
4 *
5 * Copyright (C) 2015 Texas Instruments Incorporated - https://www.ti.com
6 * Author: Roger Quadros <rogerq@ti.com>
7 */
8
9#include <linux/extcon-provider.h>
10#include <linux/gpio/consumer.h>
11#include <linux/init.h>
12#include <linux/interrupt.h>
13#include <linux/irq.h>
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/platform_device.h>
17#include <linux/slab.h>
18#include <linux/workqueue.h>
19#include <linux/pinctrl/consumer.h>
20#include <linux/mod_devicetable.h>
21
22#define USB_GPIO_DEBOUNCE_MS 20 /* ms */
23
24struct usb_extcon_info {
25 struct device *dev;
26 struct extcon_dev *edev;
27
28 struct gpio_desc *id_gpiod;
29 struct gpio_desc *vbus_gpiod;
30 int id_irq;
31 int vbus_irq;
32
33 unsigned long debounce_jiffies;
34 struct delayed_work wq_detcable;
35};
36
37static const unsigned int usb_extcon_cable[] = {
38 EXTCON_USB,
39 EXTCON_USB_HOST,
40 EXTCON_NONE,
41};
42
43/*
44 * "USB" = VBUS and "USB-HOST" = !ID, so we have:
45 * Both "USB" and "USB-HOST" can't be set as active at the
46 * same time so if "USB-HOST" is active (i.e. ID is 0) we keep "USB" inactive
47 * even if VBUS is on.
48 *
49 * State | ID | VBUS
50 * ----------------------------------------
51 * [1] USB | H | H
52 * [2] none | H | L
53 * [3] USB-HOST | L | H
54 * [4] USB-HOST | L | L
55 *
56 * In case we have only one of these signals:
57 * - VBUS only - we want to distinguish between [1] and [2], so ID is always 1.
58 * - ID only - we want to distinguish between [1] and [4], so VBUS = ID.
59*/
60static void usb_extcon_detect_cable(struct work_struct *work)
61{
62 int id, vbus;
63 struct usb_extcon_info *info = container_of(to_delayed_work(work),
64 struct usb_extcon_info,
65 wq_detcable);
66
67 /* check ID and VBUS and update cable state */
68 id = info->id_gpiod ?
69 gpiod_get_value_cansleep(info->id_gpiod) : 1;
70 vbus = info->vbus_gpiod ?
71 gpiod_get_value_cansleep(info->vbus_gpiod) : id;
72
73 /* at first we clean states which are no longer active */
74 if (id)
75 extcon_set_state_sync(info->edev, EXTCON_USB_HOST, false);
76 if (!vbus)
77 extcon_set_state_sync(info->edev, EXTCON_USB, false);
78
79 if (!id) {
80 extcon_set_state_sync(info->edev, EXTCON_USB_HOST, true);
81 } else {
82 if (vbus)
83 extcon_set_state_sync(info->edev, EXTCON_USB, true);
84 }
85}
86
87static irqreturn_t usb_irq_handler(int irq, void *dev_id)
88{
89 struct usb_extcon_info *info = dev_id;
90
91 queue_delayed_work(system_power_efficient_wq, &info->wq_detcable,
92 info->debounce_jiffies);
93
94 return IRQ_HANDLED;
95}
96
97static int usb_extcon_probe(struct platform_device *pdev)
98{
99 struct device *dev = &pdev->dev;
100 struct device_node *np = dev->of_node;
101 struct usb_extcon_info *info;
102 int ret;
103
104 if (!np)
105 return -EINVAL;
106
107 info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
108 if (!info)
109 return -ENOMEM;
110
111 info->dev = dev;
112 info->id_gpiod = devm_gpiod_get_optional(&pdev->dev, "id", GPIOD_IN);
113 info->vbus_gpiod = devm_gpiod_get_optional(&pdev->dev, "vbus",
114 GPIOD_IN);
115
116 if (!info->id_gpiod && !info->vbus_gpiod) {
117 dev_err(dev, "failed to get gpios\n");
118 return -ENODEV;
119 }
120
121 if (IS_ERR(info->id_gpiod))
122 return PTR_ERR(info->id_gpiod);
123
124 if (IS_ERR(info->vbus_gpiod))
125 return PTR_ERR(info->vbus_gpiod);
126
127 info->edev = devm_extcon_dev_allocate(dev, usb_extcon_cable);
128 if (IS_ERR(info->edev)) {
129 dev_err(dev, "failed to allocate extcon device\n");
130 return -ENOMEM;
131 }
132
133 ret = devm_extcon_dev_register(dev, info->edev);
134 if (ret < 0) {
135 dev_err(dev, "failed to register extcon device\n");
136 return ret;
137 }
138
139 if (info->id_gpiod)
140 ret = gpiod_set_debounce(info->id_gpiod,
141 USB_GPIO_DEBOUNCE_MS * 1000);
142 if (!ret && info->vbus_gpiod)
143 ret = gpiod_set_debounce(info->vbus_gpiod,
144 USB_GPIO_DEBOUNCE_MS * 1000);
145
146 if (ret < 0)
147 info->debounce_jiffies = msecs_to_jiffies(USB_GPIO_DEBOUNCE_MS);
148
149 INIT_DELAYED_WORK(&info->wq_detcable, usb_extcon_detect_cable);
150
151 if (info->id_gpiod) {
152 info->id_irq = gpiod_to_irq(info->id_gpiod);
153 if (info->id_irq < 0) {
154 dev_err(dev, "failed to get ID IRQ\n");
155 return info->id_irq;
156 }
157
158 ret = devm_request_threaded_irq(dev, info->id_irq, NULL,
159 usb_irq_handler,
160 IRQF_TRIGGER_RISING |
161 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
162 pdev->name, info);
163 if (ret < 0) {
164 dev_err(dev, "failed to request handler for ID IRQ\n");
165 return ret;
166 }
167 }
168
169 if (info->vbus_gpiod) {
170 info->vbus_irq = gpiod_to_irq(info->vbus_gpiod);
171 if (info->vbus_irq < 0) {
172 dev_err(dev, "failed to get VBUS IRQ\n");
173 return info->vbus_irq;
174 }
175
176 ret = devm_request_threaded_irq(dev, info->vbus_irq, NULL,
177 usb_irq_handler,
178 IRQF_TRIGGER_RISING |
179 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
180 pdev->name, info);
181 if (ret < 0) {
182 dev_err(dev, "failed to request handler for VBUS IRQ\n");
183 return ret;
184 }
185 }
186
187 platform_set_drvdata(pdev, info);
188 device_set_wakeup_capable(&pdev->dev, true);
189
190 /* Perform initial detection */
191 usb_extcon_detect_cable(&info->wq_detcable.work);
192
193 return 0;
194}
195
196static int usb_extcon_remove(struct platform_device *pdev)
197{
198 struct usb_extcon_info *info = platform_get_drvdata(pdev);
199
200 cancel_delayed_work_sync(&info->wq_detcable);
201 device_init_wakeup(&pdev->dev, false);
202
203 return 0;
204}
205
206#ifdef CONFIG_PM_SLEEP
207static int usb_extcon_suspend(struct device *dev)
208{
209 struct usb_extcon_info *info = dev_get_drvdata(dev);
210 int ret = 0;
211
212 if (device_may_wakeup(dev)) {
213 if (info->id_gpiod) {
214 ret = enable_irq_wake(info->id_irq);
215 if (ret)
216 return ret;
217 }
218 if (info->vbus_gpiod) {
219 ret = enable_irq_wake(info->vbus_irq);
220 if (ret) {
221 if (info->id_gpiod)
222 disable_irq_wake(info->id_irq);
223
224 return ret;
225 }
226 }
227 }
228
229 if (!device_may_wakeup(dev))
230 pinctrl_pm_select_sleep_state(dev);
231
232 return ret;
233}
234
235static int usb_extcon_resume(struct device *dev)
236{
237 struct usb_extcon_info *info = dev_get_drvdata(dev);
238 int ret = 0;
239
240 if (!device_may_wakeup(dev))
241 pinctrl_pm_select_default_state(dev);
242
243 if (device_may_wakeup(dev)) {
244 if (info->id_gpiod) {
245 ret = disable_irq_wake(info->id_irq);
246 if (ret)
247 return ret;
248 }
249 if (info->vbus_gpiod) {
250 ret = disable_irq_wake(info->vbus_irq);
251 if (ret) {
252 if (info->id_gpiod)
253 enable_irq_wake(info->id_irq);
254
255 return ret;
256 }
257 }
258 }
259
260 queue_delayed_work(system_power_efficient_wq,
261 &info->wq_detcable, 0);
262
263 return ret;
264}
265#endif
266
267static SIMPLE_DEV_PM_OPS(usb_extcon_pm_ops,
268 usb_extcon_suspend, usb_extcon_resume);
269
270static const struct of_device_id usb_extcon_dt_match[] = {
271 { .compatible = "linux,extcon-usb-gpio", },
272 { /* sentinel */ }
273};
274MODULE_DEVICE_TABLE(of, usb_extcon_dt_match);
275
276static const struct platform_device_id usb_extcon_platform_ids[] = {
277 { .name = "extcon-usb-gpio", },
278 { /* sentinel */ }
279};
280MODULE_DEVICE_TABLE(platform, usb_extcon_platform_ids);
281
282static struct platform_driver usb_extcon_driver = {
283 .probe = usb_extcon_probe,
284 .remove = usb_extcon_remove,
285 .driver = {
286 .name = "extcon-usb-gpio",
287 .pm = &usb_extcon_pm_ops,
288 .of_match_table = usb_extcon_dt_match,
289 },
290 .id_table = usb_extcon_platform_ids,
291};
292
293module_platform_driver(usb_extcon_driver);
294
295MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");
296MODULE_DESCRIPTION("USB GPIO extcon driver");
297MODULE_LICENSE("GPL v2");
1/**
2 * drivers/extcon/extcon-usb-gpio.c - USB GPIO extcon driver
3 *
4 * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com
5 * Author: Roger Quadros <rogerq@ti.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 */
16
17#include <linux/extcon-provider.h>
18#include <linux/gpio.h>
19#include <linux/gpio/consumer.h>
20#include <linux/init.h>
21#include <linux/interrupt.h>
22#include <linux/irq.h>
23#include <linux/kernel.h>
24#include <linux/module.h>
25#include <linux/of_gpio.h>
26#include <linux/platform_device.h>
27#include <linux/slab.h>
28#include <linux/workqueue.h>
29#include <linux/pinctrl/consumer.h>
30
31#define USB_GPIO_DEBOUNCE_MS 20 /* ms */
32
33struct usb_extcon_info {
34 struct device *dev;
35 struct extcon_dev *edev;
36
37 struct gpio_desc *id_gpiod;
38 struct gpio_desc *vbus_gpiod;
39 int id_irq;
40 int vbus_irq;
41
42 unsigned long debounce_jiffies;
43 struct delayed_work wq_detcable;
44};
45
46static const unsigned int usb_extcon_cable[] = {
47 EXTCON_USB,
48 EXTCON_USB_HOST,
49 EXTCON_NONE,
50};
51
52/*
53 * "USB" = VBUS and "USB-HOST" = !ID, so we have:
54 * Both "USB" and "USB-HOST" can't be set as active at the
55 * same time so if "USB-HOST" is active (i.e. ID is 0) we keep "USB" inactive
56 * even if VBUS is on.
57 *
58 * State | ID | VBUS
59 * ----------------------------------------
60 * [1] USB | H | H
61 * [2] none | H | L
62 * [3] USB-HOST | L | H
63 * [4] USB-HOST | L | L
64 *
65 * In case we have only one of these signals:
66 * - VBUS only - we want to distinguish between [1] and [2], so ID is always 1.
67 * - ID only - we want to distinguish between [1] and [4], so VBUS = ID.
68*/
69static void usb_extcon_detect_cable(struct work_struct *work)
70{
71 int id, vbus;
72 struct usb_extcon_info *info = container_of(to_delayed_work(work),
73 struct usb_extcon_info,
74 wq_detcable);
75
76 /* check ID and VBUS and update cable state */
77 id = info->id_gpiod ?
78 gpiod_get_value_cansleep(info->id_gpiod) : 1;
79 vbus = info->vbus_gpiod ?
80 gpiod_get_value_cansleep(info->vbus_gpiod) : id;
81
82 /* at first we clean states which are no longer active */
83 if (id)
84 extcon_set_state_sync(info->edev, EXTCON_USB_HOST, false);
85 if (!vbus)
86 extcon_set_state_sync(info->edev, EXTCON_USB, false);
87
88 if (!id) {
89 extcon_set_state_sync(info->edev, EXTCON_USB_HOST, true);
90 } else {
91 if (vbus)
92 extcon_set_state_sync(info->edev, EXTCON_USB, true);
93 }
94}
95
96static irqreturn_t usb_irq_handler(int irq, void *dev_id)
97{
98 struct usb_extcon_info *info = dev_id;
99
100 queue_delayed_work(system_power_efficient_wq, &info->wq_detcable,
101 info->debounce_jiffies);
102
103 return IRQ_HANDLED;
104}
105
106static int usb_extcon_probe(struct platform_device *pdev)
107{
108 struct device *dev = &pdev->dev;
109 struct device_node *np = dev->of_node;
110 struct usb_extcon_info *info;
111 int ret;
112
113 if (!np)
114 return -EINVAL;
115
116 info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
117 if (!info)
118 return -ENOMEM;
119
120 info->dev = dev;
121 info->id_gpiod = devm_gpiod_get_optional(&pdev->dev, "id", GPIOD_IN);
122 info->vbus_gpiod = devm_gpiod_get_optional(&pdev->dev, "vbus",
123 GPIOD_IN);
124
125 if (!info->id_gpiod && !info->vbus_gpiod) {
126 dev_err(dev, "failed to get gpios\n");
127 return -ENODEV;
128 }
129
130 if (IS_ERR(info->id_gpiod))
131 return PTR_ERR(info->id_gpiod);
132
133 if (IS_ERR(info->vbus_gpiod))
134 return PTR_ERR(info->vbus_gpiod);
135
136 info->edev = devm_extcon_dev_allocate(dev, usb_extcon_cable);
137 if (IS_ERR(info->edev)) {
138 dev_err(dev, "failed to allocate extcon device\n");
139 return -ENOMEM;
140 }
141
142 ret = devm_extcon_dev_register(dev, info->edev);
143 if (ret < 0) {
144 dev_err(dev, "failed to register extcon device\n");
145 return ret;
146 }
147
148 if (info->id_gpiod)
149 ret = gpiod_set_debounce(info->id_gpiod,
150 USB_GPIO_DEBOUNCE_MS * 1000);
151 if (!ret && info->vbus_gpiod)
152 ret = gpiod_set_debounce(info->vbus_gpiod,
153 USB_GPIO_DEBOUNCE_MS * 1000);
154
155 if (ret < 0)
156 info->debounce_jiffies = msecs_to_jiffies(USB_GPIO_DEBOUNCE_MS);
157
158 INIT_DELAYED_WORK(&info->wq_detcable, usb_extcon_detect_cable);
159
160 if (info->id_gpiod) {
161 info->id_irq = gpiod_to_irq(info->id_gpiod);
162 if (info->id_irq < 0) {
163 dev_err(dev, "failed to get ID IRQ\n");
164 return info->id_irq;
165 }
166
167 ret = devm_request_threaded_irq(dev, info->id_irq, NULL,
168 usb_irq_handler,
169 IRQF_TRIGGER_RISING |
170 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
171 pdev->name, info);
172 if (ret < 0) {
173 dev_err(dev, "failed to request handler for ID IRQ\n");
174 return ret;
175 }
176 }
177
178 if (info->vbus_gpiod) {
179 info->vbus_irq = gpiod_to_irq(info->vbus_gpiod);
180 if (info->vbus_irq < 0) {
181 dev_err(dev, "failed to get VBUS IRQ\n");
182 return info->vbus_irq;
183 }
184
185 ret = devm_request_threaded_irq(dev, info->vbus_irq, NULL,
186 usb_irq_handler,
187 IRQF_TRIGGER_RISING |
188 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
189 pdev->name, info);
190 if (ret < 0) {
191 dev_err(dev, "failed to request handler for VBUS IRQ\n");
192 return ret;
193 }
194 }
195
196 platform_set_drvdata(pdev, info);
197 device_set_wakeup_capable(&pdev->dev, true);
198
199 /* Perform initial detection */
200 usb_extcon_detect_cable(&info->wq_detcable.work);
201
202 return 0;
203}
204
205static int usb_extcon_remove(struct platform_device *pdev)
206{
207 struct usb_extcon_info *info = platform_get_drvdata(pdev);
208
209 cancel_delayed_work_sync(&info->wq_detcable);
210 device_init_wakeup(&pdev->dev, false);
211
212 return 0;
213}
214
215#ifdef CONFIG_PM_SLEEP
216static int usb_extcon_suspend(struct device *dev)
217{
218 struct usb_extcon_info *info = dev_get_drvdata(dev);
219 int ret = 0;
220
221 if (device_may_wakeup(dev)) {
222 if (info->id_gpiod) {
223 ret = enable_irq_wake(info->id_irq);
224 if (ret)
225 return ret;
226 }
227 if (info->vbus_gpiod) {
228 ret = enable_irq_wake(info->vbus_irq);
229 if (ret) {
230 if (info->id_gpiod)
231 disable_irq_wake(info->id_irq);
232
233 return ret;
234 }
235 }
236 }
237
238 /*
239 * We don't want to process any IRQs after this point
240 * as GPIOs used behind I2C subsystem might not be
241 * accessible until resume completes. So disable IRQ.
242 */
243 if (info->id_gpiod)
244 disable_irq(info->id_irq);
245 if (info->vbus_gpiod)
246 disable_irq(info->vbus_irq);
247
248 if (!device_may_wakeup(dev))
249 pinctrl_pm_select_sleep_state(dev);
250
251 return ret;
252}
253
254static int usb_extcon_resume(struct device *dev)
255{
256 struct usb_extcon_info *info = dev_get_drvdata(dev);
257 int ret = 0;
258
259 if (!device_may_wakeup(dev))
260 pinctrl_pm_select_default_state(dev);
261
262 if (device_may_wakeup(dev)) {
263 if (info->id_gpiod) {
264 ret = disable_irq_wake(info->id_irq);
265 if (ret)
266 return ret;
267 }
268 if (info->vbus_gpiod) {
269 ret = disable_irq_wake(info->vbus_irq);
270 if (ret) {
271 if (info->id_gpiod)
272 enable_irq_wake(info->id_irq);
273
274 return ret;
275 }
276 }
277 }
278
279 if (info->id_gpiod)
280 enable_irq(info->id_irq);
281 if (info->vbus_gpiod)
282 enable_irq(info->vbus_irq);
283
284 queue_delayed_work(system_power_efficient_wq,
285 &info->wq_detcable, 0);
286
287 return ret;
288}
289#endif
290
291static SIMPLE_DEV_PM_OPS(usb_extcon_pm_ops,
292 usb_extcon_suspend, usb_extcon_resume);
293
294static const struct of_device_id usb_extcon_dt_match[] = {
295 { .compatible = "linux,extcon-usb-gpio", },
296 { /* sentinel */ }
297};
298MODULE_DEVICE_TABLE(of, usb_extcon_dt_match);
299
300static const struct platform_device_id usb_extcon_platform_ids[] = {
301 { .name = "extcon-usb-gpio", },
302 { /* sentinel */ }
303};
304MODULE_DEVICE_TABLE(platform, usb_extcon_platform_ids);
305
306static struct platform_driver usb_extcon_driver = {
307 .probe = usb_extcon_probe,
308 .remove = usb_extcon_remove,
309 .driver = {
310 .name = "extcon-usb-gpio",
311 .pm = &usb_extcon_pm_ops,
312 .of_match_table = usb_extcon_dt_match,
313 },
314 .id_table = usb_extcon_platform_ids,
315};
316
317module_platform_driver(usb_extcon_driver);
318
319MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");
320MODULE_DESCRIPTION("USB GPIO extcon driver");
321MODULE_LICENSE("GPL v2");