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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73 /* at first we clean states which are no longer active */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.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
30#define USB_GPIO_DEBOUNCE_MS 20 /* ms */
31
32struct usb_extcon_info {
33 struct device *dev;
34 struct extcon_dev *edev;
35
36 struct gpio_desc *id_gpiod;
37 int id_irq;
38
39 unsigned long debounce_jiffies;
40 struct delayed_work wq_detcable;
41};
42
43static const unsigned int usb_extcon_cable[] = {
44 EXTCON_USB,
45 EXTCON_USB_HOST,
46 EXTCON_NONE,
47};
48
49static void usb_extcon_detect_cable(struct work_struct *work)
50{
51 int id;
52 struct usb_extcon_info *info = container_of(to_delayed_work(work),
53 struct usb_extcon_info,
54 wq_detcable);
55
56 /* check ID and update cable state */
57 id = gpiod_get_value_cansleep(info->id_gpiod);
58 if (id) {
59 /*
60 * ID = 1 means USB HOST cable detached.
61 * As we don't have event for USB peripheral cable attached,
62 * we simulate USB peripheral attach here.
63 */
64 extcon_set_cable_state_(info->edev, EXTCON_USB_HOST, false);
65 extcon_set_cable_state_(info->edev, EXTCON_USB, true);
66 } else {
67 /*
68 * ID = 0 means USB HOST cable attached.
69 * As we don't have event for USB peripheral cable detached,
70 * we simulate USB peripheral detach here.
71 */
72 extcon_set_cable_state_(info->edev, EXTCON_USB, false);
73 extcon_set_cable_state_(info->edev, EXTCON_USB_HOST, true);
74 }
75}
76
77static irqreturn_t usb_irq_handler(int irq, void *dev_id)
78{
79 struct usb_extcon_info *info = dev_id;
80
81 queue_delayed_work(system_power_efficient_wq, &info->wq_detcable,
82 info->debounce_jiffies);
83
84 return IRQ_HANDLED;
85}
86
87static int usb_extcon_probe(struct platform_device *pdev)
88{
89 struct device *dev = &pdev->dev;
90 struct device_node *np = dev->of_node;
91 struct usb_extcon_info *info;
92 int ret;
93
94 if (!np)
95 return -EINVAL;
96
97 info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
98 if (!info)
99 return -ENOMEM;
100
101 info->dev = dev;
102 info->id_gpiod = devm_gpiod_get(&pdev->dev, "id", GPIOD_IN);
103 if (IS_ERR(info->id_gpiod)) {
104 dev_err(dev, "failed to get ID GPIO\n");
105 return PTR_ERR(info->id_gpiod);
106 }
107
108 info->edev = devm_extcon_dev_allocate(dev, usb_extcon_cable);
109 if (IS_ERR(info->edev)) {
110 dev_err(dev, "failed to allocate extcon device\n");
111 return -ENOMEM;
112 }
113
114 ret = devm_extcon_dev_register(dev, info->edev);
115 if (ret < 0) {
116 dev_err(dev, "failed to register extcon device\n");
117 return ret;
118 }
119
120 ret = gpiod_set_debounce(info->id_gpiod,
121 USB_GPIO_DEBOUNCE_MS * 1000);
122 if (ret < 0)
123 info->debounce_jiffies = msecs_to_jiffies(USB_GPIO_DEBOUNCE_MS);
124
125 INIT_DELAYED_WORK(&info->wq_detcable, usb_extcon_detect_cable);
126
127 info->id_irq = gpiod_to_irq(info->id_gpiod);
128 if (info->id_irq < 0) {
129 dev_err(dev, "failed to get ID IRQ\n");
130 return info->id_irq;
131 }
132
133 ret = devm_request_threaded_irq(dev, info->id_irq, NULL,
134 usb_irq_handler,
135 IRQF_TRIGGER_RISING |
136 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
137 pdev->name, info);
138 if (ret < 0) {
139 dev_err(dev, "failed to request handler for ID IRQ\n");
140 return ret;
141 }
142
143 platform_set_drvdata(pdev, info);
144 device_init_wakeup(dev, 1);
145
146 /* Perform initial detection */
147 usb_extcon_detect_cable(&info->wq_detcable.work);
148
149 return 0;
150}
151
152static int usb_extcon_remove(struct platform_device *pdev)
153{
154 struct usb_extcon_info *info = platform_get_drvdata(pdev);
155
156 cancel_delayed_work_sync(&info->wq_detcable);
157
158 return 0;
159}
160
161#ifdef CONFIG_PM_SLEEP
162static int usb_extcon_suspend(struct device *dev)
163{
164 struct usb_extcon_info *info = dev_get_drvdata(dev);
165 int ret = 0;
166
167 if (device_may_wakeup(dev)) {
168 ret = enable_irq_wake(info->id_irq);
169 if (ret)
170 return ret;
171 }
172
173 /*
174 * We don't want to process any IRQs after this point
175 * as GPIOs used behind I2C subsystem might not be
176 * accessible until resume completes. So disable IRQ.
177 */
178 disable_irq(info->id_irq);
179
180 return ret;
181}
182
183static int usb_extcon_resume(struct device *dev)
184{
185 struct usb_extcon_info *info = dev_get_drvdata(dev);
186 int ret = 0;
187
188 if (device_may_wakeup(dev)) {
189 ret = disable_irq_wake(info->id_irq);
190 if (ret)
191 return ret;
192 }
193
194 enable_irq(info->id_irq);
195
196 return ret;
197}
198#endif
199
200static SIMPLE_DEV_PM_OPS(usb_extcon_pm_ops,
201 usb_extcon_suspend, usb_extcon_resume);
202
203static const struct of_device_id usb_extcon_dt_match[] = {
204 { .compatible = "linux,extcon-usb-gpio", },
205 { /* sentinel */ }
206};
207MODULE_DEVICE_TABLE(of, usb_extcon_dt_match);
208
209static struct platform_driver usb_extcon_driver = {
210 .probe = usb_extcon_probe,
211 .remove = usb_extcon_remove,
212 .driver = {
213 .name = "extcon-usb-gpio",
214 .pm = &usb_extcon_pm_ops,
215 .of_match_table = usb_extcon_dt_match,
216 },
217};
218
219module_platform_driver(usb_extcon_driver);
220
221MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");
222MODULE_DESCRIPTION("USB GPIO extcon driver");
223MODULE_LICENSE("GPL v2");