2 * NOP USB transceiver for all USB transceiver which are either built-in
3 * into USB IP or which are mostly autonomous.
5 * Copyright (C) 2009 Texas Instruments Inc
6 * Author: Ajay Kumar Gupta <ajay.gupta@ti.com>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 * This provides a "nop" transceiver for PHYs which are
24 * autonomous such as isp1504, isp1707, etc.
27 #include <linux/module.h>
28 #include <linux/platform_device.h>
29 #include <linux/dma-mapping.h>
30 #include <linux/usb/gadget.h>
31 #include <linux/usb/otg.h>
32 #include <linux/usb/usb_phy_generic.h>
33 #include <linux/slab.h>
34 #include <linux/clk.h>
35 #include <linux/regulator/consumer.h>
37 #include <linux/of_gpio.h>
38 #include <linux/gpio.h>
39 #include <linux/delay.h>
41 #include "phy-generic.h"
43 #define VBUS_IRQ_FLAGS \
44 (IRQF_SHARED | IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | \
47 struct platform_device *usb_phy_generic_register(void)
49 return platform_device_register_simple("usb_phy_generic",
50 PLATFORM_DEVID_AUTO, NULL, 0);
52 EXPORT_SYMBOL_GPL(usb_phy_generic_register);
54 void usb_phy_generic_unregister(struct platform_device *pdev)
56 platform_device_unregister(pdev);
58 EXPORT_SYMBOL_GPL(usb_phy_generic_unregister);
60 static int nop_set_suspend(struct usb_phy *x, int suspend)
65 static void nop_reset(struct usb_phy_generic *nop)
67 if (!nop->gpiod_reset)
70 gpiod_set_value(nop->gpiod_reset, 1);
71 usleep_range(10000, 20000);
72 gpiod_set_value(nop->gpiod_reset, 0);
75 /* interface to regulator framework */
76 static void nop_set_vbus_draw(struct usb_phy_generic *nop, unsigned mA)
78 struct regulator *vbus_draw = nop->vbus_draw;
85 enabled = nop->vbus_draw_enabled;
87 regulator_set_current_limit(vbus_draw, 0, 1000 * mA);
89 ret = regulator_enable(vbus_draw);
92 nop->vbus_draw_enabled = 1;
96 ret = regulator_disable(vbus_draw);
99 nop->vbus_draw_enabled = 0;
106 static irqreturn_t nop_gpio_vbus_thread(int irq, void *data)
108 struct usb_phy_generic *nop = data;
109 struct usb_otg *otg = nop->phy.otg;
112 vbus = gpiod_get_value(nop->gpiod_vbus);
113 if ((vbus ^ nop->vbus) == 0)
118 status = USB_EVENT_VBUS;
119 otg->state = OTG_STATE_B_PERIPHERAL;
120 nop->phy.last_event = status;
122 /* drawing a "unit load" is *always* OK, except for OTG */
123 nop_set_vbus_draw(nop, 100);
125 atomic_notifier_call_chain(&nop->phy.notifier, status,
128 nop_set_vbus_draw(nop, 0);
130 status = USB_EVENT_NONE;
131 otg->state = OTG_STATE_B_IDLE;
132 nop->phy.last_event = status;
134 atomic_notifier_call_chain(&nop->phy.notifier, status,
140 int usb_gen_phy_init(struct usb_phy *phy)
142 struct usb_phy_generic *nop = dev_get_drvdata(phy->dev);
145 if (!IS_ERR(nop->vcc)) {
146 if (regulator_enable(nop->vcc))
147 dev_err(phy->dev, "Failed to enable power\n");
150 if (!IS_ERR(nop->clk)) {
151 ret = clk_prepare_enable(nop->clk);
160 EXPORT_SYMBOL_GPL(usb_gen_phy_init);
162 void usb_gen_phy_shutdown(struct usb_phy *phy)
164 struct usb_phy_generic *nop = dev_get_drvdata(phy->dev);
166 gpiod_set_value(nop->gpiod_reset, 1);
168 if (!IS_ERR(nop->clk))
169 clk_disable_unprepare(nop->clk);
171 if (!IS_ERR(nop->vcc)) {
172 if (regulator_disable(nop->vcc))
173 dev_err(phy->dev, "Failed to disable power\n");
176 EXPORT_SYMBOL_GPL(usb_gen_phy_shutdown);
178 static int nop_set_peripheral(struct usb_otg *otg, struct usb_gadget *gadget)
188 otg->gadget = gadget;
189 if (otg->state == OTG_STATE_B_PERIPHERAL)
190 atomic_notifier_call_chain(&otg->usb_phy->notifier,
191 USB_EVENT_VBUS, otg->gadget);
193 otg->state = OTG_STATE_B_IDLE;
197 static int nop_set_host(struct usb_otg *otg, struct usb_bus *host)
211 int usb_phy_gen_create_phy(struct device *dev, struct usb_phy_generic *nop,
212 struct usb_phy_generic_platform_data *pdata)
214 enum usb_phy_type type = USB_PHY_TYPE_USB2;
218 bool needs_vcc = false;
221 struct device_node *node = dev->of_node;
223 if (of_property_read_u32(node, "clock-frequency", &clk_rate))
226 needs_vcc = of_property_read_bool(node, "vcc-supply");
227 nop->gpiod_reset = devm_gpiod_get_optional(dev, "reset",
229 err = PTR_ERR_OR_ZERO(nop->gpiod_reset);
231 nop->gpiod_vbus = devm_gpiod_get_optional(dev,
234 err = PTR_ERR_OR_ZERO(nop->gpiod_vbus);
238 clk_rate = pdata->clk_rate;
239 needs_vcc = pdata->needs_vcc;
240 if (gpio_is_valid(pdata->gpio_reset)) {
241 err = devm_gpio_request_one(dev, pdata->gpio_reset,
246 gpio_to_desc(pdata->gpio_reset);
248 nop->gpiod_vbus = pdata->gpiod_vbus;
251 if (err == -EPROBE_DEFER)
252 return -EPROBE_DEFER;
254 dev_err(dev, "Error requesting RESET or VBUS GPIO\n");
257 if (nop->gpiod_reset)
258 gpiod_direction_output(nop->gpiod_reset, 1);
260 nop->phy.otg = devm_kzalloc(dev, sizeof(*nop->phy.otg),
265 nop->clk = devm_clk_get(dev, "main_clk");
266 if (IS_ERR(nop->clk)) {
267 dev_dbg(dev, "Can't get phy clock: %ld\n",
271 if (!IS_ERR(nop->clk) && clk_rate) {
272 err = clk_set_rate(nop->clk, clk_rate);
274 dev_err(dev, "Error setting clock rate\n");
279 nop->vcc = devm_regulator_get(dev, "vcc");
280 if (IS_ERR(nop->vcc)) {
281 dev_dbg(dev, "Error getting vcc regulator: %ld\n",
284 return -EPROBE_DEFER;
288 nop->phy.dev = nop->dev;
289 nop->phy.label = "nop-xceiv";
290 nop->phy.set_suspend = nop_set_suspend;
291 nop->phy.type = type;
293 nop->phy.otg->state = OTG_STATE_UNDEFINED;
294 nop->phy.otg->usb_phy = &nop->phy;
295 nop->phy.otg->set_host = nop_set_host;
296 nop->phy.otg->set_peripheral = nop_set_peripheral;
300 EXPORT_SYMBOL_GPL(usb_phy_gen_create_phy);
302 static int usb_phy_generic_probe(struct platform_device *pdev)
304 struct device *dev = &pdev->dev;
305 struct usb_phy_generic *nop;
308 nop = devm_kzalloc(dev, sizeof(*nop), GFP_KERNEL);
312 err = usb_phy_gen_create_phy(dev, nop, dev_get_platdata(&pdev->dev));
315 if (nop->gpiod_vbus) {
316 err = devm_request_threaded_irq(&pdev->dev,
317 gpiod_to_irq(nop->gpiod_vbus),
318 NULL, nop_gpio_vbus_thread,
319 VBUS_IRQ_FLAGS, "vbus_detect",
322 dev_err(&pdev->dev, "can't request irq %i, err: %d\n",
323 gpiod_to_irq(nop->gpiod_vbus), err);
326 nop->phy.otg->state = gpiod_get_value(nop->gpiod_vbus) ?
327 OTG_STATE_B_PERIPHERAL : OTG_STATE_B_IDLE;
330 nop->phy.init = usb_gen_phy_init;
331 nop->phy.shutdown = usb_gen_phy_shutdown;
333 err = usb_add_phy_dev(&nop->phy);
335 dev_err(&pdev->dev, "can't register transceiver, err: %d\n",
340 platform_set_drvdata(pdev, nop);
345 static int usb_phy_generic_remove(struct platform_device *pdev)
347 struct usb_phy_generic *nop = platform_get_drvdata(pdev);
349 usb_remove_phy(&nop->phy);
354 static const struct of_device_id nop_xceiv_dt_ids[] = {
355 { .compatible = "usb-nop-xceiv" },
359 MODULE_DEVICE_TABLE(of, nop_xceiv_dt_ids);
361 static struct platform_driver usb_phy_generic_driver = {
362 .probe = usb_phy_generic_probe,
363 .remove = usb_phy_generic_remove,
365 .name = "usb_phy_generic",
366 .of_match_table = nop_xceiv_dt_ids,
370 static int __init usb_phy_generic_init(void)
372 return platform_driver_register(&usb_phy_generic_driver);
374 subsys_initcall(usb_phy_generic_init);
376 static void __exit usb_phy_generic_exit(void)
378 platform_driver_unregister(&usb_phy_generic_driver);
380 module_exit(usb_phy_generic_exit);
382 MODULE_ALIAS("platform:usb_phy_generic");
383 MODULE_AUTHOR("Texas Instruments Inc");
384 MODULE_DESCRIPTION("NOP USB Transceiver driver");
385 MODULE_LICENSE("GPL");