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v6.8
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * gpio-vbus.c - simple GPIO VBUS sensing driver for B peripheral devices
  4 *
  5 * Copyright (c) 2008 Philipp Zabel <philipp.zabel@gmail.com>
 
 
 
 
  6 */
  7
  8#include <linux/kernel.h>
  9#include <linux/platform_device.h>
 10#include <linux/gpio/consumer.h>
 11#include <linux/module.h>
 12#include <linux/slab.h>
 13#include <linux/interrupt.h>
 14#include <linux/usb.h>
 15#include <linux/workqueue.h>
 16
 17#include <linux/regulator/consumer.h>
 18
 19#include <linux/usb/gadget.h>
 
 20#include <linux/usb/otg.h>
 21
 22
 23/*
 24 * A simple GPIO VBUS sensing driver for B peripheral only devices
 25 * with internal transceivers. It can control a D+ pullup GPIO and
 26 * a regulator to limit the current drawn from VBUS.
 27 *
 28 * Needs to be loaded before the UDC driver that will use it.
 29 */
 30struct gpio_vbus_data {
 31	struct gpio_desc	*vbus_gpiod;
 32	struct gpio_desc	*pullup_gpiod;
 33	struct usb_phy		phy;
 34	struct device          *dev;
 35	struct regulator       *vbus_draw;
 36	int			vbus_draw_enabled;
 37	unsigned		mA;
 38	struct delayed_work	work;
 39	int			vbus;
 40	int			irq;
 41};
 42
 43
 44/*
 45 * This driver relies on "both edges" triggering.  VBUS has 100 msec to
 46 * stabilize, so the peripheral controller driver may need to cope with
 47 * some bouncing due to current surges (e.g. charging local capacitance)
 48 * and contact chatter.
 49 *
 50 * REVISIT in desperate straits, toggling between rising and falling
 51 * edges might be workable.
 52 */
 53#define VBUS_IRQ_FLAGS \
 54	(IRQF_SHARED | IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)
 55
 56
 57/* interface to regulator framework */
 58static void set_vbus_draw(struct gpio_vbus_data *gpio_vbus, unsigned mA)
 59{
 60	struct regulator *vbus_draw = gpio_vbus->vbus_draw;
 61	int enabled;
 62	int ret;
 63
 64	if (!vbus_draw)
 65		return;
 66
 67	enabled = gpio_vbus->vbus_draw_enabled;
 68	if (mA) {
 69		regulator_set_current_limit(vbus_draw, 0, 1000 * mA);
 70		if (!enabled) {
 71			ret = regulator_enable(vbus_draw);
 72			if (ret < 0)
 73				return;
 74			gpio_vbus->vbus_draw_enabled = 1;
 75		}
 76	} else {
 77		if (enabled) {
 78			ret = regulator_disable(vbus_draw);
 79			if (ret < 0)
 80				return;
 81			gpio_vbus->vbus_draw_enabled = 0;
 82		}
 83	}
 84	gpio_vbus->mA = mA;
 85}
 86
 87static int is_vbus_powered(struct gpio_vbus_data *gpio_vbus)
 88{
 89	return gpiod_get_value(gpio_vbus->vbus_gpiod);
 
 
 
 
 
 
 90}
 91
 92static void gpio_vbus_work(struct work_struct *work)
 93{
 94	struct gpio_vbus_data *gpio_vbus =
 95		container_of(work, struct gpio_vbus_data, work.work);
 96	int status, vbus;
 
 97
 98	if (!gpio_vbus->phy.otg->gadget)
 99		return;
100
101	vbus = is_vbus_powered(gpio_vbus);
102	if ((vbus ^ gpio_vbus->vbus) == 0)
103		return;
104	gpio_vbus->vbus = vbus;
105
106	/* Peripheral controllers which manage the pullup themselves won't have
107	 * a pullup GPIO configured here.  If it's configured here, we'll do
108	 * what isp1301_omap::b_peripheral() does and enable the pullup here...
109	 * although that may complicate usb_gadget_{,dis}connect() support.
110	 */
 
111
112	if (vbus) {
113		status = USB_EVENT_VBUS;
114		gpio_vbus->phy.otg->state = OTG_STATE_B_PERIPHERAL;
115		gpio_vbus->phy.last_event = status;
116		usb_gadget_vbus_connect(gpio_vbus->phy.otg->gadget);
117
118		/* drawing a "unit load" is *always* OK, except for OTG */
119		set_vbus_draw(gpio_vbus, 100);
120
121		/* optionally enable D+ pullup */
122		if (gpio_vbus->pullup_gpiod)
123			gpiod_set_value(gpio_vbus->pullup_gpiod, 1);
124
125		atomic_notifier_call_chain(&gpio_vbus->phy.notifier,
126					   status, gpio_vbus->phy.otg->gadget);
127		usb_phy_set_event(&gpio_vbus->phy, USB_EVENT_ENUMERATED);
128	} else {
129		/* optionally disable D+ pullup */
130		if (gpio_vbus->pullup_gpiod)
131			gpiod_set_value(gpio_vbus->pullup_gpiod, 0);
132
133		set_vbus_draw(gpio_vbus, 0);
134
135		usb_gadget_vbus_disconnect(gpio_vbus->phy.otg->gadget);
136		status = USB_EVENT_NONE;
137		gpio_vbus->phy.otg->state = OTG_STATE_B_IDLE;
138		gpio_vbus->phy.last_event = status;
139
140		atomic_notifier_call_chain(&gpio_vbus->phy.notifier,
141					   status, gpio_vbus->phy.otg->gadget);
142		usb_phy_set_event(&gpio_vbus->phy, USB_EVENT_NONE);
143	}
144}
145
146/* VBUS change IRQ handler */
147static irqreturn_t gpio_vbus_irq(int irq, void *data)
148{
149	struct platform_device *pdev = data;
 
150	struct gpio_vbus_data *gpio_vbus = platform_get_drvdata(pdev);
151	struct usb_otg *otg = gpio_vbus->phy.otg;
152
153	dev_dbg(&pdev->dev, "VBUS %s (gadget: %s)\n",
154		is_vbus_powered(gpio_vbus) ? "supplied" : "inactive",
155		otg->gadget ? otg->gadget->name : "none");
156
157	if (otg->gadget)
158		schedule_delayed_work(&gpio_vbus->work, msecs_to_jiffies(100));
159
160	return IRQ_HANDLED;
161}
162
163/* OTG transceiver interface */
164
165/* bind/unbind the peripheral controller */
166static int gpio_vbus_set_peripheral(struct usb_otg *otg,
167					struct usb_gadget *gadget)
168{
169	struct gpio_vbus_data *gpio_vbus;
 
170	struct platform_device *pdev;
 
171
172	gpio_vbus = container_of(otg->usb_phy, struct gpio_vbus_data, phy);
173	pdev = to_platform_device(gpio_vbus->dev);
 
 
174
175	if (!gadget) {
176		dev_dbg(&pdev->dev, "unregistering gadget '%s'\n",
177			otg->gadget->name);
178
179		/* optionally disable D+ pullup */
180		if (gpio_vbus->pullup_gpiod)
181			gpiod_set_value(gpio_vbus->pullup_gpiod, 0);
182
183		set_vbus_draw(gpio_vbus, 0);
184
185		usb_gadget_vbus_disconnect(otg->gadget);
186		otg->state = OTG_STATE_UNDEFINED;
187
188		otg->gadget = NULL;
189		return 0;
190	}
191
192	otg->gadget = gadget;
193	dev_dbg(&pdev->dev, "registered gadget '%s'\n", gadget->name);
194
195	/* initialize connection state */
196	gpio_vbus->vbus = 0; /* start with disconnected */
197	gpio_vbus_irq(gpio_vbus->irq, pdev);
198	return 0;
199}
200
201/* effective for B devices, ignored for A-peripheral */
202static int gpio_vbus_set_power(struct usb_phy *phy, unsigned mA)
203{
204	struct gpio_vbus_data *gpio_vbus;
205
206	gpio_vbus = container_of(phy, struct gpio_vbus_data, phy);
207
208	if (phy->otg->state == OTG_STATE_B_PERIPHERAL)
209		set_vbus_draw(gpio_vbus, mA);
210	return 0;
211}
212
213/* for non-OTG B devices: set/clear transceiver suspend mode */
214static int gpio_vbus_set_suspend(struct usb_phy *phy, int suspend)
215{
216	struct gpio_vbus_data *gpio_vbus;
217
218	gpio_vbus = container_of(phy, struct gpio_vbus_data, phy);
219
220	/* draw max 0 mA from vbus in suspend mode; or the previously
221	 * recorded amount of current if not suspended
222	 *
223	 * NOTE: high powered configs (mA > 100) may draw up to 2.5 mA
224	 * if they're wake-enabled ... we don't handle that yet.
225	 */
226	return gpio_vbus_set_power(phy, suspend ? 0 : gpio_vbus->mA);
227}
228
229/* platform driver interface */
230
231static int gpio_vbus_probe(struct platform_device *pdev)
232{
 
233	struct gpio_vbus_data *gpio_vbus;
234	struct resource *res;
235	struct device *dev = &pdev->dev;
236	int err, irq;
237	unsigned long irqflags;
238
 
 
 
 
239	gpio_vbus = devm_kzalloc(&pdev->dev, sizeof(struct gpio_vbus_data),
240				 GFP_KERNEL);
241	if (!gpio_vbus)
242		return -ENOMEM;
243
244	gpio_vbus->phy.otg = devm_kzalloc(&pdev->dev, sizeof(struct usb_otg),
245					  GFP_KERNEL);
246	if (!gpio_vbus->phy.otg)
247		return -ENOMEM;
248
249	platform_set_drvdata(pdev, gpio_vbus);
250	gpio_vbus->dev = &pdev->dev;
251	gpio_vbus->phy.label = "gpio-vbus";
252	gpio_vbus->phy.dev = gpio_vbus->dev;
253	gpio_vbus->phy.set_power = gpio_vbus_set_power;
254	gpio_vbus->phy.set_suspend = gpio_vbus_set_suspend;
255
256	gpio_vbus->phy.otg->state = OTG_STATE_UNDEFINED;
257	gpio_vbus->phy.otg->usb_phy = &gpio_vbus->phy;
258	gpio_vbus->phy.otg->set_peripheral = gpio_vbus_set_peripheral;
259
260	/* Look up the VBUS sensing GPIO */
261	gpio_vbus->vbus_gpiod = devm_gpiod_get(dev, "vbus", GPIOD_IN);
262	if (IS_ERR(gpio_vbus->vbus_gpiod)) {
263		err = PTR_ERR(gpio_vbus->vbus_gpiod);
264		dev_err(&pdev->dev, "can't request vbus gpio, err: %d\n", err);
265		return err;
266	}
267	gpiod_set_consumer_name(gpio_vbus->vbus_gpiod, "vbus_detect");
268
269	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
270	if (res) {
271		irq = res->start;
272		irqflags = (res->flags & IRQF_TRIGGER_MASK) | IRQF_SHARED;
273	} else {
274		irq = gpiod_to_irq(gpio_vbus->vbus_gpiod);
275		irqflags = VBUS_IRQ_FLAGS;
276	}
277
278	gpio_vbus->irq = irq;
279
280	/*
281	 * The VBUS sensing GPIO should have a pulldown, which will normally be
282	 * part of a resistor ladder turning a 4.0V-5.25V level on VBUS into a
283	 * value the GPIO detects as active. Some systems will use comparators.
284	 * Get the optional D+ or D- pullup GPIO. If the data line pullup is
285	 * in use, initialize it to "not pulling up"
286	 */
287	gpio_vbus->pullup_gpiod = devm_gpiod_get_optional(dev, "pullup",
288							  GPIOD_OUT_LOW);
289	if (IS_ERR(gpio_vbus->pullup_gpiod)) {
290		err = PTR_ERR(gpio_vbus->pullup_gpiod);
291		dev_err(&pdev->dev, "can't request pullup gpio, err: %d\n",
292			err);
293		return err;
294	}
295	if (gpio_vbus->pullup_gpiod)
296		gpiod_set_consumer_name(gpio_vbus->pullup_gpiod, "udc_pullup");
297
298	err = devm_request_irq(&pdev->dev, irq, gpio_vbus_irq, irqflags,
299			       "vbus_detect", pdev);
300	if (err) {
301		dev_err(&pdev->dev, "can't request irq %i, err: %d\n",
302			irq, err);
303		return err;
304	}
305
306	INIT_DELAYED_WORK(&gpio_vbus->work, gpio_vbus_work);
307
308	gpio_vbus->vbus_draw = devm_regulator_get(&pdev->dev, "vbus_draw");
309	if (IS_ERR(gpio_vbus->vbus_draw)) {
310		dev_dbg(&pdev->dev, "can't get vbus_draw regulator, err: %ld\n",
311			PTR_ERR(gpio_vbus->vbus_draw));
312		gpio_vbus->vbus_draw = NULL;
313	}
314
315	/* only active when a gadget is registered */
316	err = usb_add_phy(&gpio_vbus->phy, USB_PHY_TYPE_USB2);
317	if (err) {
318		dev_err(&pdev->dev, "can't register transceiver, err: %d\n",
319			err);
320		return err;
321	}
322
323	/* TODO: wakeup could be enabled here with device_init_wakeup(dev, 1) */
324
325	return 0;
326}
327
328static void gpio_vbus_remove(struct platform_device *pdev)
329{
330	struct gpio_vbus_data *gpio_vbus = platform_get_drvdata(pdev);
331
332	device_init_wakeup(&pdev->dev, 0);
333	cancel_delayed_work_sync(&gpio_vbus->work);
334
335	usb_remove_phy(&gpio_vbus->phy);
 
 
336}
337
338#ifdef CONFIG_PM
339static int gpio_vbus_pm_suspend(struct device *dev)
340{
341	struct gpio_vbus_data *gpio_vbus = dev_get_drvdata(dev);
342
343	if (device_may_wakeup(dev))
344		enable_irq_wake(gpio_vbus->irq);
345
346	return 0;
347}
348
349static int gpio_vbus_pm_resume(struct device *dev)
350{
351	struct gpio_vbus_data *gpio_vbus = dev_get_drvdata(dev);
352
353	if (device_may_wakeup(dev))
354		disable_irq_wake(gpio_vbus->irq);
355
356	return 0;
357}
358
359static const struct dev_pm_ops gpio_vbus_dev_pm_ops = {
360	.suspend	= gpio_vbus_pm_suspend,
361	.resume		= gpio_vbus_pm_resume,
362};
363#endif
364
365MODULE_ALIAS("platform:gpio-vbus");
366
367/*
368 * NOTE: this driver matches against "gpio-usb-b-connector" for
369 * devices that do NOT support role switch.
370 */
371static const struct of_device_id gpio_vbus_of_match[] = {
372	{
373		.compatible = "gpio-usb-b-connector",
374	},
375	{},
376};
377
378static struct platform_driver gpio_vbus_driver = {
379	.driver = {
380		.name  = "gpio-vbus",
381#ifdef CONFIG_PM
382		.pm = &gpio_vbus_dev_pm_ops,
383#endif
384		.of_match_table = gpio_vbus_of_match,
385	},
386	.probe		= gpio_vbus_probe,
387	.remove_new	= gpio_vbus_remove,
388};
389
390module_platform_driver(gpio_vbus_driver);
391
392MODULE_DESCRIPTION("simple GPIO controlled OTG transceiver driver");
393MODULE_AUTHOR("Philipp Zabel");
394MODULE_LICENSE("GPL");
v4.6
 
  1/*
  2 * gpio-vbus.c - simple GPIO VBUS sensing driver for B peripheral devices
  3 *
  4 * Copyright (c) 2008 Philipp Zabel <philipp.zabel@gmail.com>
  5 *
  6 * This program is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License version 2 as
  8 * published by the Free Software Foundation.
  9 */
 10
 11#include <linux/kernel.h>
 12#include <linux/platform_device.h>
 13#include <linux/gpio.h>
 14#include <linux/module.h>
 15#include <linux/slab.h>
 16#include <linux/interrupt.h>
 17#include <linux/usb.h>
 18#include <linux/workqueue.h>
 19
 20#include <linux/regulator/consumer.h>
 21
 22#include <linux/usb/gadget.h>
 23#include <linux/usb/gpio_vbus.h>
 24#include <linux/usb/otg.h>
 25
 26
 27/*
 28 * A simple GPIO VBUS sensing driver for B peripheral only devices
 29 * with internal transceivers. It can control a D+ pullup GPIO and
 30 * a regulator to limit the current drawn from VBUS.
 31 *
 32 * Needs to be loaded before the UDC driver that will use it.
 33 */
 34struct gpio_vbus_data {
 
 
 35	struct usb_phy		phy;
 36	struct device          *dev;
 37	struct regulator       *vbus_draw;
 38	int			vbus_draw_enabled;
 39	unsigned		mA;
 40	struct delayed_work	work;
 41	int			vbus;
 42	int			irq;
 43};
 44
 45
 46/*
 47 * This driver relies on "both edges" triggering.  VBUS has 100 msec to
 48 * stabilize, so the peripheral controller driver may need to cope with
 49 * some bouncing due to current surges (e.g. charging local capacitance)
 50 * and contact chatter.
 51 *
 52 * REVISIT in desperate straits, toggling between rising and falling
 53 * edges might be workable.
 54 */
 55#define VBUS_IRQ_FLAGS \
 56	(IRQF_SHARED | IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)
 57
 58
 59/* interface to regulator framework */
 60static void set_vbus_draw(struct gpio_vbus_data *gpio_vbus, unsigned mA)
 61{
 62	struct regulator *vbus_draw = gpio_vbus->vbus_draw;
 63	int enabled;
 64	int ret;
 65
 66	if (!vbus_draw)
 67		return;
 68
 69	enabled = gpio_vbus->vbus_draw_enabled;
 70	if (mA) {
 71		regulator_set_current_limit(vbus_draw, 0, 1000 * mA);
 72		if (!enabled) {
 73			ret = regulator_enable(vbus_draw);
 74			if (ret < 0)
 75				return;
 76			gpio_vbus->vbus_draw_enabled = 1;
 77		}
 78	} else {
 79		if (enabled) {
 80			ret = regulator_disable(vbus_draw);
 81			if (ret < 0)
 82				return;
 83			gpio_vbus->vbus_draw_enabled = 0;
 84		}
 85	}
 86	gpio_vbus->mA = mA;
 87}
 88
 89static int is_vbus_powered(struct gpio_vbus_mach_info *pdata)
 90{
 91	int vbus;
 92
 93	vbus = gpio_get_value(pdata->gpio_vbus);
 94	if (pdata->gpio_vbus_inverted)
 95		vbus = !vbus;
 96
 97	return vbus;
 98}
 99
100static void gpio_vbus_work(struct work_struct *work)
101{
102	struct gpio_vbus_data *gpio_vbus =
103		container_of(work, struct gpio_vbus_data, work.work);
104	struct gpio_vbus_mach_info *pdata = dev_get_platdata(gpio_vbus->dev);
105	int gpio, status, vbus;
106
107	if (!gpio_vbus->phy.otg->gadget)
108		return;
109
110	vbus = is_vbus_powered(pdata);
111	if ((vbus ^ gpio_vbus->vbus) == 0)
112		return;
113	gpio_vbus->vbus = vbus;
114
115	/* Peripheral controllers which manage the pullup themselves won't have
116	 * gpio_pullup configured here.  If it's configured here, we'll do what
117	 * isp1301_omap::b_peripheral() does and enable the pullup here... although
118	 * that may complicate usb_gadget_{,dis}connect() support.
119	 */
120	gpio = pdata->gpio_pullup;
121
122	if (vbus) {
123		status = USB_EVENT_VBUS;
124		gpio_vbus->phy.otg->state = OTG_STATE_B_PERIPHERAL;
125		gpio_vbus->phy.last_event = status;
126		usb_gadget_vbus_connect(gpio_vbus->phy.otg->gadget);
127
128		/* drawing a "unit load" is *always* OK, except for OTG */
129		set_vbus_draw(gpio_vbus, 100);
130
131		/* optionally enable D+ pullup */
132		if (gpio_is_valid(gpio))
133			gpio_set_value(gpio, !pdata->gpio_pullup_inverted);
134
135		atomic_notifier_call_chain(&gpio_vbus->phy.notifier,
136					   status, gpio_vbus->phy.otg->gadget);
137		usb_phy_set_event(&gpio_vbus->phy, USB_EVENT_ENUMERATED);
138	} else {
139		/* optionally disable D+ pullup */
140		if (gpio_is_valid(gpio))
141			gpio_set_value(gpio, pdata->gpio_pullup_inverted);
142
143		set_vbus_draw(gpio_vbus, 0);
144
145		usb_gadget_vbus_disconnect(gpio_vbus->phy.otg->gadget);
146		status = USB_EVENT_NONE;
147		gpio_vbus->phy.otg->state = OTG_STATE_B_IDLE;
148		gpio_vbus->phy.last_event = status;
149
150		atomic_notifier_call_chain(&gpio_vbus->phy.notifier,
151					   status, gpio_vbus->phy.otg->gadget);
152		usb_phy_set_event(&gpio_vbus->phy, USB_EVENT_NONE);
153	}
154}
155
156/* VBUS change IRQ handler */
157static irqreturn_t gpio_vbus_irq(int irq, void *data)
158{
159	struct platform_device *pdev = data;
160	struct gpio_vbus_mach_info *pdata = dev_get_platdata(&pdev->dev);
161	struct gpio_vbus_data *gpio_vbus = platform_get_drvdata(pdev);
162	struct usb_otg *otg = gpio_vbus->phy.otg;
163
164	dev_dbg(&pdev->dev, "VBUS %s (gadget: %s)\n",
165		is_vbus_powered(pdata) ? "supplied" : "inactive",
166		otg->gadget ? otg->gadget->name : "none");
167
168	if (otg->gadget)
169		schedule_delayed_work(&gpio_vbus->work, msecs_to_jiffies(100));
170
171	return IRQ_HANDLED;
172}
173
174/* OTG transceiver interface */
175
176/* bind/unbind the peripheral controller */
177static int gpio_vbus_set_peripheral(struct usb_otg *otg,
178					struct usb_gadget *gadget)
179{
180	struct gpio_vbus_data *gpio_vbus;
181	struct gpio_vbus_mach_info *pdata;
182	struct platform_device *pdev;
183	int gpio;
184
185	gpio_vbus = container_of(otg->usb_phy, struct gpio_vbus_data, phy);
186	pdev = to_platform_device(gpio_vbus->dev);
187	pdata = dev_get_platdata(gpio_vbus->dev);
188	gpio = pdata->gpio_pullup;
189
190	if (!gadget) {
191		dev_dbg(&pdev->dev, "unregistering gadget '%s'\n",
192			otg->gadget->name);
193
194		/* optionally disable D+ pullup */
195		if (gpio_is_valid(gpio))
196			gpio_set_value(gpio, pdata->gpio_pullup_inverted);
197
198		set_vbus_draw(gpio_vbus, 0);
199
200		usb_gadget_vbus_disconnect(otg->gadget);
201		otg->state = OTG_STATE_UNDEFINED;
202
203		otg->gadget = NULL;
204		return 0;
205	}
206
207	otg->gadget = gadget;
208	dev_dbg(&pdev->dev, "registered gadget '%s'\n", gadget->name);
209
210	/* initialize connection state */
211	gpio_vbus->vbus = 0; /* start with disconnected */
212	gpio_vbus_irq(gpio_vbus->irq, pdev);
213	return 0;
214}
215
216/* effective for B devices, ignored for A-peripheral */
217static int gpio_vbus_set_power(struct usb_phy *phy, unsigned mA)
218{
219	struct gpio_vbus_data *gpio_vbus;
220
221	gpio_vbus = container_of(phy, struct gpio_vbus_data, phy);
222
223	if (phy->otg->state == OTG_STATE_B_PERIPHERAL)
224		set_vbus_draw(gpio_vbus, mA);
225	return 0;
226}
227
228/* for non-OTG B devices: set/clear transceiver suspend mode */
229static int gpio_vbus_set_suspend(struct usb_phy *phy, int suspend)
230{
231	struct gpio_vbus_data *gpio_vbus;
232
233	gpio_vbus = container_of(phy, struct gpio_vbus_data, phy);
234
235	/* draw max 0 mA from vbus in suspend mode; or the previously
236	 * recorded amount of current if not suspended
237	 *
238	 * NOTE: high powered configs (mA > 100) may draw up to 2.5 mA
239	 * if they're wake-enabled ... we don't handle that yet.
240	 */
241	return gpio_vbus_set_power(phy, suspend ? 0 : gpio_vbus->mA);
242}
243
244/* platform driver interface */
245
246static int gpio_vbus_probe(struct platform_device *pdev)
247{
248	struct gpio_vbus_mach_info *pdata = dev_get_platdata(&pdev->dev);
249	struct gpio_vbus_data *gpio_vbus;
250	struct resource *res;
251	int err, gpio, irq;
 
252	unsigned long irqflags;
253
254	if (!pdata || !gpio_is_valid(pdata->gpio_vbus))
255		return -EINVAL;
256	gpio = pdata->gpio_vbus;
257
258	gpio_vbus = devm_kzalloc(&pdev->dev, sizeof(struct gpio_vbus_data),
259				 GFP_KERNEL);
260	if (!gpio_vbus)
261		return -ENOMEM;
262
263	gpio_vbus->phy.otg = devm_kzalloc(&pdev->dev, sizeof(struct usb_otg),
264					  GFP_KERNEL);
265	if (!gpio_vbus->phy.otg)
266		return -ENOMEM;
267
268	platform_set_drvdata(pdev, gpio_vbus);
269	gpio_vbus->dev = &pdev->dev;
270	gpio_vbus->phy.label = "gpio-vbus";
271	gpio_vbus->phy.dev = gpio_vbus->dev;
272	gpio_vbus->phy.set_power = gpio_vbus_set_power;
273	gpio_vbus->phy.set_suspend = gpio_vbus_set_suspend;
274
275	gpio_vbus->phy.otg->state = OTG_STATE_UNDEFINED;
276	gpio_vbus->phy.otg->usb_phy = &gpio_vbus->phy;
277	gpio_vbus->phy.otg->set_peripheral = gpio_vbus_set_peripheral;
278
279	err = devm_gpio_request(&pdev->dev, gpio, "vbus_detect");
280	if (err) {
281		dev_err(&pdev->dev, "can't request vbus gpio %d, err: %d\n",
282			gpio, err);
 
283		return err;
284	}
285	gpio_direction_input(gpio);
286
287	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
288	if (res) {
289		irq = res->start;
290		irqflags = (res->flags & IRQF_TRIGGER_MASK) | IRQF_SHARED;
291	} else {
292		irq = gpio_to_irq(gpio);
293		irqflags = VBUS_IRQ_FLAGS;
294	}
295
296	gpio_vbus->irq = irq;
297
298	/* if data line pullup is in use, initialize it to "not pulling up" */
299	gpio = pdata->gpio_pullup;
300	if (gpio_is_valid(gpio)) {
301		err = devm_gpio_request(&pdev->dev, gpio, "udc_pullup");
302		if (err) {
303			dev_err(&pdev->dev,
304				"can't request pullup gpio %d, err: %d\n",
305				gpio, err);
306			return err;
307		}
308		gpio_direction_output(gpio, pdata->gpio_pullup_inverted);
 
 
 
309	}
 
 
310
311	err = devm_request_irq(&pdev->dev, irq, gpio_vbus_irq, irqflags,
312			       "vbus_detect", pdev);
313	if (err) {
314		dev_err(&pdev->dev, "can't request irq %i, err: %d\n",
315			irq, err);
316		return err;
317	}
318
319	INIT_DELAYED_WORK(&gpio_vbus->work, gpio_vbus_work);
320
321	gpio_vbus->vbus_draw = devm_regulator_get(&pdev->dev, "vbus_draw");
322	if (IS_ERR(gpio_vbus->vbus_draw)) {
323		dev_dbg(&pdev->dev, "can't get vbus_draw regulator, err: %ld\n",
324			PTR_ERR(gpio_vbus->vbus_draw));
325		gpio_vbus->vbus_draw = NULL;
326	}
327
328	/* only active when a gadget is registered */
329	err = usb_add_phy(&gpio_vbus->phy, USB_PHY_TYPE_USB2);
330	if (err) {
331		dev_err(&pdev->dev, "can't register transceiver, err: %d\n",
332			err);
333		return err;
334	}
335
336	device_init_wakeup(&pdev->dev, pdata->wakeup);
337
338	return 0;
339}
340
341static int gpio_vbus_remove(struct platform_device *pdev)
342{
343	struct gpio_vbus_data *gpio_vbus = platform_get_drvdata(pdev);
344
345	device_init_wakeup(&pdev->dev, 0);
346	cancel_delayed_work_sync(&gpio_vbus->work);
347
348	usb_remove_phy(&gpio_vbus->phy);
349
350	return 0;
351}
352
353#ifdef CONFIG_PM
354static int gpio_vbus_pm_suspend(struct device *dev)
355{
356	struct gpio_vbus_data *gpio_vbus = dev_get_drvdata(dev);
357
358	if (device_may_wakeup(dev))
359		enable_irq_wake(gpio_vbus->irq);
360
361	return 0;
362}
363
364static int gpio_vbus_pm_resume(struct device *dev)
365{
366	struct gpio_vbus_data *gpio_vbus = dev_get_drvdata(dev);
367
368	if (device_may_wakeup(dev))
369		disable_irq_wake(gpio_vbus->irq);
370
371	return 0;
372}
373
374static const struct dev_pm_ops gpio_vbus_dev_pm_ops = {
375	.suspend	= gpio_vbus_pm_suspend,
376	.resume		= gpio_vbus_pm_resume,
377};
378#endif
379
380MODULE_ALIAS("platform:gpio-vbus");
381
 
 
 
 
 
 
 
 
 
 
 
382static struct platform_driver gpio_vbus_driver = {
383	.driver = {
384		.name  = "gpio-vbus",
385#ifdef CONFIG_PM
386		.pm = &gpio_vbus_dev_pm_ops,
387#endif
 
388	},
389	.probe		= gpio_vbus_probe,
390	.remove		= gpio_vbus_remove,
391};
392
393module_platform_driver(gpio_vbus_driver);
394
395MODULE_DESCRIPTION("simple GPIO controlled OTG transceiver driver");
396MODULE_AUTHOR("Philipp Zabel");
397MODULE_LICENSE("GPL");