1 // SPDX-License-Identifier: GPL-2.0+
3 * NOP USB transceiver for all USB transceiver which are either built-in
4 * into USB IP or which are mostly autonomous.
6 * Copyright (C) 2009 Texas Instruments Inc
7 * Author: Ajay Kumar Gupta <ajay.gupta@ti.com>
10 * This provides a "nop" transceiver for PHYs which are
11 * autonomous such as isp1504, isp1707, etc.
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/usb/gadget.h>
18 #include <linux/usb/otg.h>
19 #include <linux/usb/usb_phy_generic.h>
20 #include <linux/slab.h>
21 #include <linux/clk.h>
22 #include <linux/regulator/consumer.h>
24 #include <linux/gpio/consumer.h>
25 #include <linux/delay.h>
27 #include "phy-generic.h"
29 #define VBUS_IRQ_FLAGS \
30 (IRQF_SHARED | IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | \
33 struct platform_device *usb_phy_generic_register(void)
35 return platform_device_register_simple("usb_phy_generic",
36 PLATFORM_DEVID_AUTO, NULL, 0);
38 EXPORT_SYMBOL_GPL(usb_phy_generic_register);
40 void usb_phy_generic_unregister(struct platform_device *pdev)
42 platform_device_unregister(pdev);
44 EXPORT_SYMBOL_GPL(usb_phy_generic_unregister);
46 static int nop_set_suspend(struct usb_phy *x, int suspend)
48 struct usb_phy_generic *nop = dev_get_drvdata(x->dev);
52 if (!IS_ERR(nop->clk))
53 clk_disable_unprepare(nop->clk);
54 if (!IS_ERR(nop->vcc) && !device_may_wakeup(x->dev))
55 ret = regulator_disable(nop->vcc);
57 if (!IS_ERR(nop->vcc) && !device_may_wakeup(x->dev))
58 ret = regulator_enable(nop->vcc);
59 if (!IS_ERR(nop->clk))
60 clk_prepare_enable(nop->clk);
66 static void nop_reset(struct usb_phy_generic *nop)
68 if (!nop->gpiod_reset)
71 gpiod_set_value_cansleep(nop->gpiod_reset, 1);
72 usleep_range(10000, 20000);
73 gpiod_set_value_cansleep(nop->gpiod_reset, 0);
76 /* interface to regulator framework */
77 static void nop_set_vbus_draw(struct usb_phy_generic *nop, unsigned mA)
79 struct regulator *vbus_draw = nop->vbus_draw;
86 enabled = nop->vbus_draw_enabled;
88 regulator_set_current_limit(vbus_draw, 0, 1000 * mA);
90 ret = regulator_enable(vbus_draw);
93 nop->vbus_draw_enabled = 1;
97 ret = regulator_disable(vbus_draw);
100 nop->vbus_draw_enabled = 0;
107 static irqreturn_t nop_gpio_vbus_thread(int irq, void *data)
109 struct usb_phy_generic *nop = data;
110 struct usb_otg *otg = nop->phy.otg;
113 vbus = gpiod_get_value(nop->gpiod_vbus);
114 if ((vbus ^ nop->vbus) == 0)
119 status = USB_EVENT_VBUS;
120 otg->state = OTG_STATE_B_PERIPHERAL;
121 nop->phy.last_event = status;
123 /* drawing a "unit load" is *always* OK, except for OTG */
124 nop_set_vbus_draw(nop, 100);
126 atomic_notifier_call_chain(&nop->phy.notifier, status,
129 nop_set_vbus_draw(nop, 0);
131 status = USB_EVENT_NONE;
132 otg->state = OTG_STATE_B_IDLE;
133 nop->phy.last_event = status;
135 atomic_notifier_call_chain(&nop->phy.notifier, status,
141 int usb_gen_phy_init(struct usb_phy *phy)
143 struct usb_phy_generic *nop = dev_get_drvdata(phy->dev);
146 if (!IS_ERR(nop->vcc)) {
147 if (regulator_enable(nop->vcc))
148 dev_err(phy->dev, "Failed to enable power\n");
151 if (!IS_ERR(nop->clk)) {
152 ret = clk_prepare_enable(nop->clk);
161 EXPORT_SYMBOL_GPL(usb_gen_phy_init);
163 void usb_gen_phy_shutdown(struct usb_phy *phy)
165 struct usb_phy_generic *nop = dev_get_drvdata(phy->dev);
167 gpiod_set_value_cansleep(nop->gpiod_reset, 1);
169 if (!IS_ERR(nop->clk))
170 clk_disable_unprepare(nop->clk);
172 if (!IS_ERR(nop->vcc)) {
173 if (regulator_disable(nop->vcc))
174 dev_err(phy->dev, "Failed to disable power\n");
177 EXPORT_SYMBOL_GPL(usb_gen_phy_shutdown);
179 static int nop_set_peripheral(struct usb_otg *otg, struct usb_gadget *gadget)
189 otg->gadget = gadget;
190 if (otg->state == OTG_STATE_B_PERIPHERAL)
191 atomic_notifier_call_chain(&otg->usb_phy->notifier,
192 USB_EVENT_VBUS, otg->gadget);
194 otg->state = OTG_STATE_B_IDLE;
198 static int nop_set_host(struct usb_otg *otg, struct usb_bus *host)
212 int usb_phy_gen_create_phy(struct device *dev, struct usb_phy_generic *nop)
214 enum usb_phy_type type = USB_PHY_TYPE_USB2;
218 bool needs_clk = false;
221 struct device_node *node = dev->of_node;
223 if (of_property_read_u32(node, "clock-frequency", &clk_rate))
226 needs_clk = of_property_read_bool(node, "clocks");
228 nop->gpiod_reset = devm_gpiod_get_optional(dev, "reset",
230 err = PTR_ERR_OR_ZERO(nop->gpiod_reset);
232 nop->gpiod_vbus = devm_gpiod_get_optional(dev,
235 err = PTR_ERR_OR_ZERO(nop->gpiod_vbus);
239 return dev_err_probe(dev, err,
240 "Error requesting RESET or VBUS GPIO\n");
241 if (nop->gpiod_reset)
242 gpiod_direction_output(nop->gpiod_reset, 1);
244 nop->phy.otg = devm_kzalloc(dev, sizeof(*nop->phy.otg),
249 nop->clk = devm_clk_get(dev, "main_clk");
250 if (IS_ERR(nop->clk)) {
251 dev_dbg(dev, "Can't get phy clock: %ld\n",
254 return PTR_ERR(nop->clk);
257 if (!IS_ERR(nop->clk) && clk_rate) {
258 err = clk_set_rate(nop->clk, clk_rate);
260 dev_err(dev, "Error setting clock rate\n");
265 nop->vcc = devm_regulator_get_optional(dev, "vcc");
266 if (IS_ERR(nop->vcc) && PTR_ERR(nop->vcc) != -ENODEV)
267 return dev_err_probe(dev, PTR_ERR(nop->vcc),
268 "could not get vcc regulator\n");
270 nop->vbus_draw = devm_regulator_get_exclusive(dev, "vbus");
271 if (PTR_ERR(nop->vbus_draw) == -ENODEV)
272 nop->vbus_draw = NULL;
273 if (IS_ERR(nop->vbus_draw))
274 return dev_err_probe(dev, PTR_ERR(nop->vbus_draw),
275 "could not get vbus regulator\n");
278 nop->phy.dev = nop->dev;
279 nop->phy.label = "nop-xceiv";
280 nop->phy.set_suspend = nop_set_suspend;
281 nop->phy.type = type;
283 nop->phy.otg->state = OTG_STATE_UNDEFINED;
284 nop->phy.otg->usb_phy = &nop->phy;
285 nop->phy.otg->set_host = nop_set_host;
286 nop->phy.otg->set_peripheral = nop_set_peripheral;
290 EXPORT_SYMBOL_GPL(usb_phy_gen_create_phy);
292 static int usb_phy_generic_probe(struct platform_device *pdev)
294 struct device *dev = &pdev->dev;
295 struct device_node *dn = dev->of_node;
296 struct usb_phy_generic *nop;
299 nop = devm_kzalloc(dev, sizeof(*nop), GFP_KERNEL);
303 err = usb_phy_gen_create_phy(dev, nop);
306 if (nop->gpiod_vbus) {
307 err = devm_request_threaded_irq(&pdev->dev,
308 gpiod_to_irq(nop->gpiod_vbus),
309 NULL, nop_gpio_vbus_thread,
310 VBUS_IRQ_FLAGS, "vbus_detect",
313 dev_err(&pdev->dev, "can't request irq %i, err: %d\n",
314 gpiod_to_irq(nop->gpiod_vbus), err);
317 nop->phy.otg->state = gpiod_get_value(nop->gpiod_vbus) ?
318 OTG_STATE_B_PERIPHERAL : OTG_STATE_B_IDLE;
321 nop->phy.init = usb_gen_phy_init;
322 nop->phy.shutdown = usb_gen_phy_shutdown;
324 err = usb_add_phy_dev(&nop->phy);
326 dev_err(&pdev->dev, "can't register transceiver, err: %d\n",
331 platform_set_drvdata(pdev, nop);
333 device_set_wakeup_capable(&pdev->dev,
334 of_property_read_bool(dn, "wakeup-source"));
339 static void usb_phy_generic_remove(struct platform_device *pdev)
341 struct usb_phy_generic *nop = platform_get_drvdata(pdev);
343 usb_remove_phy(&nop->phy);
346 static const struct of_device_id nop_xceiv_dt_ids[] = {
347 { .compatible = "usb-nop-xceiv" },
351 MODULE_DEVICE_TABLE(of, nop_xceiv_dt_ids);
353 static struct platform_driver usb_phy_generic_driver = {
354 .probe = usb_phy_generic_probe,
355 .remove_new = usb_phy_generic_remove,
357 .name = "usb_phy_generic",
358 .of_match_table = nop_xceiv_dt_ids,
362 static int __init usb_phy_generic_init(void)
364 return platform_driver_register(&usb_phy_generic_driver);
366 subsys_initcall(usb_phy_generic_init);
368 static void __exit usb_phy_generic_exit(void)
370 platform_driver_unregister(&usb_phy_generic_driver);
372 module_exit(usb_phy_generic_exit);
374 MODULE_ALIAS("platform:usb_phy_generic");
375 MODULE_AUTHOR("Texas Instruments Inc");
376 MODULE_DESCRIPTION("NOP USB Transceiver driver");
377 MODULE_LICENSE("GPL");