x86/xen: resume timer irqs early
[linux/fpc-iii.git] / drivers / usb / phy / phy-gpio-vbus-usb.c
blob02799a5efcd448b8c38ee85de7cad8452ffbb617
1 /*
2 * gpio-vbus.c - simple GPIO VBUS sensing driver for B peripheral devices
4 * Copyright (c) 2008 Philipp Zabel <philipp.zabel@gmail.com>
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 */
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>
20 #include <linux/regulator/consumer.h>
22 #include <linux/usb/gadget.h>
23 #include <linux/usb/gpio_vbus.h>
24 #include <linux/usb/otg.h>
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.
32 * Needs to be loaded before the UDC driver that will use it.
34 struct 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;
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.
52 * REVISIT in desperate straits, toggling between rising and falling
53 * edges might be workable.
55 #define VBUS_IRQ_FLAGS \
56 (IRQF_SHARED | IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)
59 /* interface to regulator framework */
60 static void set_vbus_draw(struct gpio_vbus_data *gpio_vbus, unsigned mA)
62 struct regulator *vbus_draw = gpio_vbus->vbus_draw;
63 int enabled;
64 int ret;
66 if (!vbus_draw)
67 return;
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;
78 } else {
79 if (enabled) {
80 ret = regulator_disable(vbus_draw);
81 if (ret < 0)
82 return;
83 gpio_vbus->vbus_draw_enabled = 0;
86 gpio_vbus->mA = mA;
89 static int is_vbus_powered(struct gpio_vbus_mach_info *pdata)
91 int vbus;
93 vbus = gpio_get_value(pdata->gpio_vbus);
94 if (pdata->gpio_vbus_inverted)
95 vbus = !vbus;
97 return vbus;
100 static void gpio_vbus_work(struct work_struct *work)
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;
107 if (!gpio_vbus->phy.otg->gadget)
108 return;
110 vbus = is_vbus_powered(pdata);
111 if ((vbus ^ gpio_vbus->vbus) == 0)
112 return;
113 gpio_vbus->vbus = vbus;
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.
120 gpio = pdata->gpio_pullup;
122 if (vbus) {
123 status = USB_EVENT_VBUS;
124 gpio_vbus->phy.state = OTG_STATE_B_PERIPHERAL;
125 gpio_vbus->phy.last_event = status;
126 usb_gadget_vbus_connect(gpio_vbus->phy.otg->gadget);
128 /* drawing a "unit load" is *always* OK, except for OTG */
129 set_vbus_draw(gpio_vbus, 100);
131 /* optionally enable D+ pullup */
132 if (gpio_is_valid(gpio))
133 gpio_set_value(gpio, !pdata->gpio_pullup_inverted);
135 atomic_notifier_call_chain(&gpio_vbus->phy.notifier,
136 status, gpio_vbus->phy.otg->gadget);
137 } else {
138 /* optionally disable D+ pullup */
139 if (gpio_is_valid(gpio))
140 gpio_set_value(gpio, pdata->gpio_pullup_inverted);
142 set_vbus_draw(gpio_vbus, 0);
144 usb_gadget_vbus_disconnect(gpio_vbus->phy.otg->gadget);
145 status = USB_EVENT_NONE;
146 gpio_vbus->phy.state = OTG_STATE_B_IDLE;
147 gpio_vbus->phy.last_event = status;
149 atomic_notifier_call_chain(&gpio_vbus->phy.notifier,
150 status, gpio_vbus->phy.otg->gadget);
154 /* VBUS change IRQ handler */
155 static irqreturn_t gpio_vbus_irq(int irq, void *data)
157 struct platform_device *pdev = data;
158 struct gpio_vbus_mach_info *pdata = dev_get_platdata(&pdev->dev);
159 struct gpio_vbus_data *gpio_vbus = platform_get_drvdata(pdev);
160 struct usb_otg *otg = gpio_vbus->phy.otg;
162 dev_dbg(&pdev->dev, "VBUS %s (gadget: %s)\n",
163 is_vbus_powered(pdata) ? "supplied" : "inactive",
164 otg->gadget ? otg->gadget->name : "none");
166 if (otg->gadget)
167 schedule_delayed_work(&gpio_vbus->work, msecs_to_jiffies(100));
169 return IRQ_HANDLED;
172 /* OTG transceiver interface */
174 /* bind/unbind the peripheral controller */
175 static int gpio_vbus_set_peripheral(struct usb_otg *otg,
176 struct usb_gadget *gadget)
178 struct gpio_vbus_data *gpio_vbus;
179 struct gpio_vbus_mach_info *pdata;
180 struct platform_device *pdev;
181 int gpio;
183 gpio_vbus = container_of(otg->phy, struct gpio_vbus_data, phy);
184 pdev = to_platform_device(gpio_vbus->dev);
185 pdata = dev_get_platdata(gpio_vbus->dev);
186 gpio = pdata->gpio_pullup;
188 if (!gadget) {
189 dev_dbg(&pdev->dev, "unregistering gadget '%s'\n",
190 otg->gadget->name);
192 /* optionally disable D+ pullup */
193 if (gpio_is_valid(gpio))
194 gpio_set_value(gpio, pdata->gpio_pullup_inverted);
196 set_vbus_draw(gpio_vbus, 0);
198 usb_gadget_vbus_disconnect(otg->gadget);
199 otg->phy->state = OTG_STATE_UNDEFINED;
201 otg->gadget = NULL;
202 return 0;
205 otg->gadget = gadget;
206 dev_dbg(&pdev->dev, "registered gadget '%s'\n", gadget->name);
208 /* initialize connection state */
209 gpio_vbus->vbus = 0; /* start with disconnected */
210 gpio_vbus_irq(gpio_vbus->irq, pdev);
211 return 0;
214 /* effective for B devices, ignored for A-peripheral */
215 static int gpio_vbus_set_power(struct usb_phy *phy, unsigned mA)
217 struct gpio_vbus_data *gpio_vbus;
219 gpio_vbus = container_of(phy, struct gpio_vbus_data, phy);
221 if (phy->state == OTG_STATE_B_PERIPHERAL)
222 set_vbus_draw(gpio_vbus, mA);
223 return 0;
226 /* for non-OTG B devices: set/clear transceiver suspend mode */
227 static int gpio_vbus_set_suspend(struct usb_phy *phy, int suspend)
229 struct gpio_vbus_data *gpio_vbus;
231 gpio_vbus = container_of(phy, struct gpio_vbus_data, phy);
233 /* draw max 0 mA from vbus in suspend mode; or the previously
234 * recorded amount of current if not suspended
236 * NOTE: high powered configs (mA > 100) may draw up to 2.5 mA
237 * if they're wake-enabled ... we don't handle that yet.
239 return gpio_vbus_set_power(phy, suspend ? 0 : gpio_vbus->mA);
242 /* platform driver interface */
244 static int gpio_vbus_probe(struct platform_device *pdev)
246 struct gpio_vbus_mach_info *pdata = dev_get_platdata(&pdev->dev);
247 struct gpio_vbus_data *gpio_vbus;
248 struct resource *res;
249 int err, gpio, irq;
250 unsigned long irqflags;
252 if (!pdata || !gpio_is_valid(pdata->gpio_vbus))
253 return -EINVAL;
254 gpio = pdata->gpio_vbus;
256 gpio_vbus = kzalloc(sizeof(struct gpio_vbus_data), GFP_KERNEL);
257 if (!gpio_vbus)
258 return -ENOMEM;
260 gpio_vbus->phy.otg = kzalloc(sizeof(struct usb_otg), GFP_KERNEL);
261 if (!gpio_vbus->phy.otg) {
262 kfree(gpio_vbus);
263 return -ENOMEM;
266 platform_set_drvdata(pdev, gpio_vbus);
267 gpio_vbus->dev = &pdev->dev;
268 gpio_vbus->phy.label = "gpio-vbus";
269 gpio_vbus->phy.dev = gpio_vbus->dev;
270 gpio_vbus->phy.set_power = gpio_vbus_set_power;
271 gpio_vbus->phy.set_suspend = gpio_vbus_set_suspend;
272 gpio_vbus->phy.state = OTG_STATE_UNDEFINED;
274 gpio_vbus->phy.otg->phy = &gpio_vbus->phy;
275 gpio_vbus->phy.otg->set_peripheral = gpio_vbus_set_peripheral;
277 err = gpio_request(gpio, "vbus_detect");
278 if (err) {
279 dev_err(&pdev->dev, "can't request vbus gpio %d, err: %d\n",
280 gpio, err);
281 goto err_gpio;
283 gpio_direction_input(gpio);
285 res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
286 if (res) {
287 irq = res->start;
288 irqflags = (res->flags & IRQF_TRIGGER_MASK) | IRQF_SHARED;
289 } else {
290 irq = gpio_to_irq(gpio);
291 irqflags = VBUS_IRQ_FLAGS;
294 gpio_vbus->irq = irq;
296 /* if data line pullup is in use, initialize it to "not pulling up" */
297 gpio = pdata->gpio_pullup;
298 if (gpio_is_valid(gpio)) {
299 err = gpio_request(gpio, "udc_pullup");
300 if (err) {
301 dev_err(&pdev->dev,
302 "can't request pullup gpio %d, err: %d\n",
303 gpio, err);
304 gpio_free(pdata->gpio_vbus);
305 goto err_gpio;
307 gpio_direction_output(gpio, pdata->gpio_pullup_inverted);
310 err = request_irq(irq, gpio_vbus_irq, irqflags, "vbus_detect", pdev);
311 if (err) {
312 dev_err(&pdev->dev, "can't request irq %i, err: %d\n",
313 irq, err);
314 goto err_irq;
317 ATOMIC_INIT_NOTIFIER_HEAD(&gpio_vbus->phy.notifier);
319 INIT_DELAYED_WORK(&gpio_vbus->work, gpio_vbus_work);
321 gpio_vbus->vbus_draw = 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;
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 goto err_otg;
336 device_init_wakeup(&pdev->dev, pdata->wakeup);
338 return 0;
339 err_otg:
340 regulator_put(gpio_vbus->vbus_draw);
341 free_irq(irq, pdev);
342 err_irq:
343 if (gpio_is_valid(pdata->gpio_pullup))
344 gpio_free(pdata->gpio_pullup);
345 gpio_free(pdata->gpio_vbus);
346 err_gpio:
347 kfree(gpio_vbus->phy.otg);
348 kfree(gpio_vbus);
349 return err;
352 static int gpio_vbus_remove(struct platform_device *pdev)
354 struct gpio_vbus_data *gpio_vbus = platform_get_drvdata(pdev);
355 struct gpio_vbus_mach_info *pdata = dev_get_platdata(&pdev->dev);
356 int gpio = pdata->gpio_vbus;
358 device_init_wakeup(&pdev->dev, 0);
359 cancel_delayed_work_sync(&gpio_vbus->work);
360 regulator_put(gpio_vbus->vbus_draw);
362 usb_remove_phy(&gpio_vbus->phy);
364 free_irq(gpio_vbus->irq, pdev);
365 if (gpio_is_valid(pdata->gpio_pullup))
366 gpio_free(pdata->gpio_pullup);
367 gpio_free(gpio);
368 kfree(gpio_vbus->phy.otg);
369 kfree(gpio_vbus);
371 return 0;
374 #ifdef CONFIG_PM
375 static int gpio_vbus_pm_suspend(struct device *dev)
377 struct gpio_vbus_data *gpio_vbus = dev_get_drvdata(dev);
379 if (device_may_wakeup(dev))
380 enable_irq_wake(gpio_vbus->irq);
382 return 0;
385 static int gpio_vbus_pm_resume(struct device *dev)
387 struct gpio_vbus_data *gpio_vbus = dev_get_drvdata(dev);
389 if (device_may_wakeup(dev))
390 disable_irq_wake(gpio_vbus->irq);
392 return 0;
395 static const struct dev_pm_ops gpio_vbus_dev_pm_ops = {
396 .suspend = gpio_vbus_pm_suspend,
397 .resume = gpio_vbus_pm_resume,
399 #endif
401 MODULE_ALIAS("platform:gpio-vbus");
403 static struct platform_driver gpio_vbus_driver = {
404 .driver = {
405 .name = "gpio-vbus",
406 .owner = THIS_MODULE,
407 #ifdef CONFIG_PM
408 .pm = &gpio_vbus_dev_pm_ops,
409 #endif
411 .probe = gpio_vbus_probe,
412 .remove = gpio_vbus_remove,
415 module_platform_driver(gpio_vbus_driver);
417 MODULE_DESCRIPTION("simple GPIO controlled OTG transceiver driver");
418 MODULE_AUTHOR("Philipp Zabel");
419 MODULE_LICENSE("GPL");