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v5.9
  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 - http://www.ti.com
  6 * Author: Roger Quadros <rogerq@ti.com>
  7 */
  8
  9#include <linux/extcon-provider.h>
 10#include <linux/gpio.h>
 11#include <linux/gpio/consumer.h>
 12#include <linux/init.h>
 13#include <linux/interrupt.h>
 14#include <linux/irq.h>
 15#include <linux/kernel.h>
 16#include <linux/module.h>
 17#include <linux/of_gpio.h>
 18#include <linux/platform_device.h>
 19#include <linux/slab.h>
 20#include <linux/workqueue.h>
 21#include <linux/pinctrl/consumer.h>
 
 22
 23#define USB_GPIO_DEBOUNCE_MS	20	/* ms */
 24
 25struct usb_extcon_info {
 26	struct device *dev;
 27	struct extcon_dev *edev;
 28
 29	struct gpio_desc *id_gpiod;
 30	struct gpio_desc *vbus_gpiod;
 31	int id_irq;
 32	int vbus_irq;
 33
 34	unsigned long debounce_jiffies;
 35	struct delayed_work wq_detcable;
 36};
 37
 38static const unsigned int usb_extcon_cable[] = {
 39	EXTCON_USB,
 40	EXTCON_USB_HOST,
 41	EXTCON_NONE,
 42};
 43
 44/*
 45 * "USB" = VBUS and "USB-HOST" = !ID, so we have:
 46 * Both "USB" and "USB-HOST" can't be set as active at the
 47 * same time so if "USB-HOST" is active (i.e. ID is 0)  we keep "USB" inactive
 48 * even if VBUS is on.
 49 *
 50 *  State              |    ID   |   VBUS
 51 * ----------------------------------------
 52 *  [1] USB            |    H    |    H
 53 *  [2] none           |    H    |    L
 54 *  [3] USB-HOST       |    L    |    H
 55 *  [4] USB-HOST       |    L    |    L
 56 *
 57 * In case we have only one of these signals:
 58 * - VBUS only - we want to distinguish between [1] and [2], so ID is always 1.
 59 * - ID only - we want to distinguish between [1] and [4], so VBUS = ID.
 60*/
 61static void usb_extcon_detect_cable(struct work_struct *work)
 62{
 63	int id, vbus;
 64	struct usb_extcon_info *info = container_of(to_delayed_work(work),
 65						    struct usb_extcon_info,
 66						    wq_detcable);
 67
 68	/* check ID and VBUS and update cable state */
 69	id = info->id_gpiod ?
 70		gpiod_get_value_cansleep(info->id_gpiod) : 1;
 71	vbus = info->vbus_gpiod ?
 72		gpiod_get_value_cansleep(info->vbus_gpiod) : id;
 73
 74	/* at first we clean states which are no longer active */
 75	if (id)
 76		extcon_set_state_sync(info->edev, EXTCON_USB_HOST, false);
 77	if (!vbus)
 78		extcon_set_state_sync(info->edev, EXTCON_USB, false);
 79
 80	if (!id) {
 81		extcon_set_state_sync(info->edev, EXTCON_USB_HOST, true);
 82	} else {
 83		if (vbus)
 84			extcon_set_state_sync(info->edev, EXTCON_USB, true);
 85	}
 86}
 87
 88static irqreturn_t usb_irq_handler(int irq, void *dev_id)
 89{
 90	struct usb_extcon_info *info = dev_id;
 91
 92	queue_delayed_work(system_power_efficient_wq, &info->wq_detcable,
 93			   info->debounce_jiffies);
 94
 95	return IRQ_HANDLED;
 96}
 97
 98static int usb_extcon_probe(struct platform_device *pdev)
 99{
100	struct device *dev = &pdev->dev;
101	struct device_node *np = dev->of_node;
102	struct usb_extcon_info *info;
103	int ret;
104
105	if (!np)
106		return -EINVAL;
107
108	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
109	if (!info)
110		return -ENOMEM;
111
112	info->dev = dev;
113	info->id_gpiod = devm_gpiod_get_optional(&pdev->dev, "id", GPIOD_IN);
114	info->vbus_gpiod = devm_gpiod_get_optional(&pdev->dev, "vbus",
115						   GPIOD_IN);
116
117	if (!info->id_gpiod && !info->vbus_gpiod) {
118		dev_err(dev, "failed to get gpios\n");
119		return -ENODEV;
120	}
121
122	if (IS_ERR(info->id_gpiod))
123		return PTR_ERR(info->id_gpiod);
124
125	if (IS_ERR(info->vbus_gpiod))
126		return PTR_ERR(info->vbus_gpiod);
127
128	info->edev = devm_extcon_dev_allocate(dev, usb_extcon_cable);
129	if (IS_ERR(info->edev)) {
130		dev_err(dev, "failed to allocate extcon device\n");
131		return -ENOMEM;
132	}
133
134	ret = devm_extcon_dev_register(dev, info->edev);
135	if (ret < 0) {
136		dev_err(dev, "failed to register extcon device\n");
137		return ret;
138	}
139
140	if (info->id_gpiod)
141		ret = gpiod_set_debounce(info->id_gpiod,
142					 USB_GPIO_DEBOUNCE_MS * 1000);
143	if (!ret && info->vbus_gpiod)
144		ret = gpiod_set_debounce(info->vbus_gpiod,
145					 USB_GPIO_DEBOUNCE_MS * 1000);
146
147	if (ret < 0)
148		info->debounce_jiffies = msecs_to_jiffies(USB_GPIO_DEBOUNCE_MS);
149
150	INIT_DELAYED_WORK(&info->wq_detcable, usb_extcon_detect_cable);
151
152	if (info->id_gpiod) {
153		info->id_irq = gpiod_to_irq(info->id_gpiod);
154		if (info->id_irq < 0) {
155			dev_err(dev, "failed to get ID IRQ\n");
156			return info->id_irq;
157		}
158
159		ret = devm_request_threaded_irq(dev, info->id_irq, NULL,
160						usb_irq_handler,
161						IRQF_TRIGGER_RISING |
162						IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
163						pdev->name, info);
164		if (ret < 0) {
165			dev_err(dev, "failed to request handler for ID IRQ\n");
166			return ret;
167		}
168	}
169
170	if (info->vbus_gpiod) {
171		info->vbus_irq = gpiod_to_irq(info->vbus_gpiod);
172		if (info->vbus_irq < 0) {
173			dev_err(dev, "failed to get VBUS IRQ\n");
174			return info->vbus_irq;
175		}
176
177		ret = devm_request_threaded_irq(dev, info->vbus_irq, NULL,
178						usb_irq_handler,
179						IRQF_TRIGGER_RISING |
180						IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
181						pdev->name, info);
182		if (ret < 0) {
183			dev_err(dev, "failed to request handler for VBUS IRQ\n");
184			return ret;
185		}
186	}
187
188	platform_set_drvdata(pdev, info);
189	device_set_wakeup_capable(&pdev->dev, true);
190
191	/* Perform initial detection */
192	usb_extcon_detect_cable(&info->wq_detcable.work);
193
194	return 0;
195}
196
197static int usb_extcon_remove(struct platform_device *pdev)
198{
199	struct usb_extcon_info *info = platform_get_drvdata(pdev);
200
201	cancel_delayed_work_sync(&info->wq_detcable);
202	device_init_wakeup(&pdev->dev, false);
203
204	return 0;
205}
206
207#ifdef CONFIG_PM_SLEEP
208static int usb_extcon_suspend(struct device *dev)
209{
210	struct usb_extcon_info *info = dev_get_drvdata(dev);
211	int ret = 0;
212
213	if (device_may_wakeup(dev)) {
214		if (info->id_gpiod) {
215			ret = enable_irq_wake(info->id_irq);
216			if (ret)
217				return ret;
218		}
219		if (info->vbus_gpiod) {
220			ret = enable_irq_wake(info->vbus_irq);
221			if (ret) {
222				if (info->id_gpiod)
223					disable_irq_wake(info->id_irq);
224
225				return ret;
226			}
227		}
228	}
229
230	/*
231	 * We don't want to process any IRQs after this point
232	 * as GPIOs used behind I2C subsystem might not be
233	 * accessible until resume completes. So disable IRQ.
234	 */
235	if (info->id_gpiod)
236		disable_irq(info->id_irq);
237	if (info->vbus_gpiod)
238		disable_irq(info->vbus_irq);
239
240	if (!device_may_wakeup(dev))
241		pinctrl_pm_select_sleep_state(dev);
242
243	return ret;
244}
245
246static int usb_extcon_resume(struct device *dev)
247{
248	struct usb_extcon_info *info = dev_get_drvdata(dev);
249	int ret = 0;
250
251	if (!device_may_wakeup(dev))
252		pinctrl_pm_select_default_state(dev);
253
254	if (device_may_wakeup(dev)) {
255		if (info->id_gpiod) {
256			ret = disable_irq_wake(info->id_irq);
257			if (ret)
258				return ret;
259		}
260		if (info->vbus_gpiod) {
261			ret = disable_irq_wake(info->vbus_irq);
262			if (ret) {
263				if (info->id_gpiod)
264					enable_irq_wake(info->id_irq);
265
266				return ret;
267			}
268		}
269	}
270
271	if (info->id_gpiod)
272		enable_irq(info->id_irq);
273	if (info->vbus_gpiod)
274		enable_irq(info->vbus_irq);
275
276	queue_delayed_work(system_power_efficient_wq,
277			   &info->wq_detcable, 0);
278
279	return ret;
280}
281#endif
282
283static SIMPLE_DEV_PM_OPS(usb_extcon_pm_ops,
284			 usb_extcon_suspend, usb_extcon_resume);
285
286static const struct of_device_id usb_extcon_dt_match[] = {
287	{ .compatible = "linux,extcon-usb-gpio", },
288	{ /* sentinel */ }
289};
290MODULE_DEVICE_TABLE(of, usb_extcon_dt_match);
291
292static const struct platform_device_id usb_extcon_platform_ids[] = {
293	{ .name = "extcon-usb-gpio", },
294	{ /* sentinel */ }
295};
296MODULE_DEVICE_TABLE(platform, usb_extcon_platform_ids);
297
298static struct platform_driver usb_extcon_driver = {
299	.probe		= usb_extcon_probe,
300	.remove		= usb_extcon_remove,
301	.driver		= {
302		.name	= "extcon-usb-gpio",
303		.pm	= &usb_extcon_pm_ops,
304		.of_match_table = usb_extcon_dt_match,
305	},
306	.id_table = usb_extcon_platform_ids,
307};
308
309module_platform_driver(usb_extcon_driver);
310
311MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");
312MODULE_DESCRIPTION("USB GPIO extcon driver");
313MODULE_LICENSE("GPL v2");
v6.2
  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");