1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * NOP USB transceiver for all USB transceiver which are either built-in
4 * into USB IP or which are mostly autonomous.
5 *
6 * Copyright (C) 2009 Texas Instruments Inc
7 * Author: Ajay Kumar Gupta <ajay.gupta@ti.com>
8 *
9 * Current status:
10 * This provides a "nop" transceiver for PHYs which are
11 * autonomous such as isp1504, isp1707, etc.
12 */
13
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>
23#include <linux/of.h>
24#include <linux/gpio/consumer.h>
25#include <linux/delay.h>
26
27#include "phy-generic.h"
28
29#define VBUS_IRQ_FLAGS \
30 (IRQF_SHARED | IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | \
31 IRQF_ONESHOT)
32
33struct platform_device *usb_phy_generic_register(void)
34{
35 return platform_device_register_simple(name: "usb_phy_generic",
36 PLATFORM_DEVID_AUTO, NULL, num: 0);
37}
38EXPORT_SYMBOL_GPL(usb_phy_generic_register);
39
40void usb_phy_generic_unregister(struct platform_device *pdev)
41{
42 platform_device_unregister(pdev);
43}
44EXPORT_SYMBOL_GPL(usb_phy_generic_unregister);
45
46static int nop_set_suspend(struct usb_phy *x, int suspend)
47{
48 struct usb_phy_generic *nop = dev_get_drvdata(dev: x->dev);
49 int ret = 0;
50
51 if (suspend) {
52 if (!IS_ERR(ptr: nop->clk))
53 clk_disable_unprepare(clk: nop->clk);
54 if (!IS_ERR(ptr: nop->vcc) && !device_may_wakeup(dev: x->dev))
55 ret = regulator_disable(regulator: nop->vcc);
56 } else {
57 if (!IS_ERR(ptr: nop->vcc) && !device_may_wakeup(dev: x->dev))
58 ret = regulator_enable(regulator: nop->vcc);
59 if (!IS_ERR(ptr: nop->clk))
60 clk_prepare_enable(clk: nop->clk);
61 }
62
63 return ret;
64}
65
66static void nop_reset(struct usb_phy_generic *nop)
67{
68 if (!nop->gpiod_reset)
69 return;
70
71 gpiod_set_value_cansleep(desc: nop->gpiod_reset, value: 1);
72 usleep_range(min: 10000, max: 20000);
73 gpiod_set_value_cansleep(desc: nop->gpiod_reset, value: 0);
74}
75
76/* interface to regulator framework */
77static int nop_set_vbus(struct usb_otg *otg, bool enable)
78{
79 int ret = 0;
80 struct usb_phy_generic *nop = dev_get_drvdata(dev: otg->usb_phy->dev);
81
82 if (!nop->vbus_draw)
83 return 0;
84
85 if (enable && !nop->vbus_draw_enabled) {
86 ret = regulator_enable(regulator: nop->vbus_draw);
87 if (ret)
88 nop->vbus_draw_enabled = false;
89 else
90 nop->vbus_draw_enabled = true;
91
92 } else if (!enable && nop->vbus_draw_enabled) {
93 ret = regulator_disable(regulator: nop->vbus_draw);
94 nop->vbus_draw_enabled = false;
95 }
96 return ret;
97}
98
99
100static irqreturn_t nop_gpio_vbus_thread(int irq, void *data)
101{
102 struct usb_phy_generic *nop = data;
103 struct usb_otg *otg = nop->phy.otg;
104 int vbus, status;
105
106 vbus = gpiod_get_value(desc: nop->gpiod_vbus);
107 if ((vbus ^ nop->vbus) == 0)
108 return IRQ_HANDLED;
109 nop->vbus = vbus;
110
111 if (vbus) {
112 status = USB_EVENT_VBUS;
113 otg->state = OTG_STATE_B_PERIPHERAL;
114 nop->phy.last_event = status;
115
116 atomic_notifier_call_chain(nh: &nop->phy.notifier, val: status,
117 v: otg->gadget);
118 } else {
119 status = USB_EVENT_NONE;
120 otg->state = OTG_STATE_B_IDLE;
121 nop->phy.last_event = status;
122
123 atomic_notifier_call_chain(nh: &nop->phy.notifier, val: status,
124 v: otg->gadget);
125 }
126 return IRQ_HANDLED;
127}
128
129int usb_gen_phy_init(struct usb_phy *phy)
130{
131 struct usb_phy_generic *nop = dev_get_drvdata(dev: phy->dev);
132 int ret;
133
134 if (!IS_ERR(ptr: nop->vcc)) {
135 if (regulator_enable(regulator: nop->vcc))
136 dev_err(phy->dev, "Failed to enable power\n");
137 }
138
139 if (!IS_ERR(ptr: nop->clk)) {
140 ret = clk_prepare_enable(clk: nop->clk);
141 if (ret)
142 return ret;
143 }
144
145 nop_reset(nop);
146
147 return 0;
148}
149EXPORT_SYMBOL_GPL(usb_gen_phy_init);
150
151void usb_gen_phy_shutdown(struct usb_phy *phy)
152{
153 struct usb_phy_generic *nop = dev_get_drvdata(dev: phy->dev);
154
155 gpiod_set_value_cansleep(desc: nop->gpiod_reset, value: 1);
156
157 if (!IS_ERR(ptr: nop->clk))
158 clk_disable_unprepare(clk: nop->clk);
159
160 if (!IS_ERR(ptr: nop->vcc)) {
161 if (regulator_disable(regulator: nop->vcc))
162 dev_err(phy->dev, "Failed to disable power\n");
163 }
164}
165EXPORT_SYMBOL_GPL(usb_gen_phy_shutdown);
166
167static int nop_set_peripheral(struct usb_otg *otg, struct usb_gadget *gadget)
168{
169 if (!otg)
170 return -ENODEV;
171
172 if (!gadget) {
173 otg->gadget = NULL;
174 return -ENODEV;
175 }
176
177 otg->gadget = gadget;
178 if (otg->state == OTG_STATE_B_PERIPHERAL)
179 atomic_notifier_call_chain(nh: &otg->usb_phy->notifier,
180 val: USB_EVENT_VBUS, v: otg->gadget);
181 else
182 otg->state = OTG_STATE_B_IDLE;
183 return 0;
184}
185
186static int nop_set_host(struct usb_otg *otg, struct usb_bus *host)
187{
188 if (!otg)
189 return -ENODEV;
190
191 if (!host) {
192 otg->host = NULL;
193 return -ENODEV;
194 }
195
196 otg->host = host;
197 return 0;
198}
199
200int usb_phy_gen_create_phy(struct device *dev, struct usb_phy_generic *nop)
201{
202 enum usb_phy_type type = USB_PHY_TYPE_USB2;
203 int err = 0;
204
205 u32 clk_rate = 0;
206 bool needs_clk = false;
207
208 if (dev->of_node) {
209 struct device_node *node = dev->of_node;
210
211 if (of_property_read_u32(np: node, propname: "clock-frequency", out_value: &clk_rate))
212 clk_rate = 0;
213
214 needs_clk = of_property_read_bool(np: node, propname: "clocks");
215 }
216 nop->gpiod_reset = devm_gpiod_get_optional(dev, con_id: "reset",
217 flags: GPIOD_ASIS);
218 err = PTR_ERR_OR_ZERO(ptr: nop->gpiod_reset);
219 if (!err) {
220 nop->gpiod_vbus = devm_gpiod_get_optional(dev,
221 con_id: "vbus-detect",
222 flags: GPIOD_ASIS);
223 err = PTR_ERR_OR_ZERO(ptr: nop->gpiod_vbus);
224 }
225
226 if (err)
227 return dev_err_probe(dev, err,
228 fmt: "Error requesting RESET or VBUS GPIO\n");
229 if (nop->gpiod_reset)
230 gpiod_direction_output(desc: nop->gpiod_reset, value: 1);
231
232 nop->phy.otg = devm_kzalloc(dev, size: sizeof(*nop->phy.otg),
233 GFP_KERNEL);
234 if (!nop->phy.otg)
235 return -ENOMEM;
236
237 nop->clk = devm_clk_get(dev, id: "main_clk");
238 if (IS_ERR(ptr: nop->clk)) {
239 dev_dbg(dev, "Can't get phy clock: %ld\n",
240 PTR_ERR(nop->clk));
241 if (needs_clk)
242 return PTR_ERR(ptr: nop->clk);
243 }
244
245 if (!IS_ERR(ptr: nop->clk) && clk_rate) {
246 err = clk_set_rate(clk: nop->clk, rate: clk_rate);
247 if (err) {
248 dev_err(dev, "Error setting clock rate\n");
249 return err;
250 }
251 }
252
253 nop->vcc = devm_regulator_get_optional(dev, id: "vcc");
254 if (IS_ERR(ptr: nop->vcc) && PTR_ERR(ptr: nop->vcc) != -ENODEV)
255 return dev_err_probe(dev, err: PTR_ERR(ptr: nop->vcc),
256 fmt: "could not get vcc regulator\n");
257
258 nop->vbus_draw = devm_regulator_get_exclusive(dev, id: "vbus");
259 if (PTR_ERR(ptr: nop->vbus_draw) == -ENODEV)
260 nop->vbus_draw = NULL;
261 if (IS_ERR(ptr: nop->vbus_draw))
262 return dev_err_probe(dev, err: PTR_ERR(ptr: nop->vbus_draw),
263 fmt: "could not get vbus regulator\n");
264
265 nop->dev = dev;
266 nop->phy.dev = nop->dev;
267 nop->phy.label = "nop-xceiv";
268 nop->phy.set_suspend = nop_set_suspend;
269 nop->phy.type = type;
270
271 nop->phy.otg->state = OTG_STATE_UNDEFINED;
272 nop->phy.otg->usb_phy = &nop->phy;
273 nop->phy.otg->set_host = nop_set_host;
274 nop->phy.otg->set_peripheral = nop_set_peripheral;
275 nop->phy.otg->set_vbus = nop_set_vbus;
276
277 return 0;
278}
279EXPORT_SYMBOL_GPL(usb_phy_gen_create_phy);
280
281static int usb_phy_generic_probe(struct platform_device *pdev)
282{
283 struct device *dev = &pdev->dev;
284 struct device_node *dn = dev->of_node;
285 struct usb_phy_generic *nop;
286 int err;
287
288 nop = devm_kzalloc(dev, size: sizeof(*nop), GFP_KERNEL);
289 if (!nop)
290 return -ENOMEM;
291
292 err = usb_phy_gen_create_phy(dev, nop);
293 if (err)
294 return err;
295 if (nop->gpiod_vbus) {
296 err = devm_request_threaded_irq(dev: &pdev->dev,
297 irq: gpiod_to_irq(desc: nop->gpiod_vbus),
298 NULL, thread_fn: nop_gpio_vbus_thread,
299 VBUS_IRQ_FLAGS, devname: "vbus_detect",
300 dev_id: nop);
301 if (err) {
302 dev_err(&pdev->dev, "can't request irq %i, err: %d\n",
303 gpiod_to_irq(nop->gpiod_vbus), err);
304 return err;
305 }
306 nop->phy.otg->state = gpiod_get_value(desc: nop->gpiod_vbus) ?
307 OTG_STATE_B_PERIPHERAL : OTG_STATE_B_IDLE;
308 }
309
310 nop->phy.init = usb_gen_phy_init;
311 nop->phy.shutdown = usb_gen_phy_shutdown;
312
313 err = usb_add_phy_dev(&nop->phy);
314 if (err) {
315 dev_err(&pdev->dev, "can't register transceiver, err: %d\n",
316 err);
317 return err;
318 }
319
320 platform_set_drvdata(pdev, data: nop);
321
322 device_set_wakeup_capable(dev: &pdev->dev,
323 capable: of_property_read_bool(np: dn, propname: "wakeup-source"));
324
325 return 0;
326}
327
328static void usb_phy_generic_remove(struct platform_device *pdev)
329{
330 struct usb_phy_generic *nop = platform_get_drvdata(pdev);
331
332 usb_remove_phy(&nop->phy);
333
334 if (nop->vbus_draw && nop->vbus_draw_enabled)
335 regulator_disable(regulator: nop->vbus_draw);
336}
337
338static const struct of_device_id nop_xceiv_dt_ids[] = {
339 { .compatible = "usb-nop-xceiv" },
340 { }
341};
342
343MODULE_DEVICE_TABLE(of, nop_xceiv_dt_ids);
344
345static struct platform_driver usb_phy_generic_driver = {
346 .probe = usb_phy_generic_probe,
347 .remove_new = usb_phy_generic_remove,
348 .driver = {
349 .name = "usb_phy_generic",
350 .of_match_table = nop_xceiv_dt_ids,
351 },
352};
353
354static int __init usb_phy_generic_init(void)
355{
356 return platform_driver_register(&usb_phy_generic_driver);
357}
358subsys_initcall(usb_phy_generic_init);
359
360static void __exit usb_phy_generic_exit(void)
361{
362 platform_driver_unregister(&usb_phy_generic_driver);
363}
364module_exit(usb_phy_generic_exit);
365
366MODULE_ALIAS("platform:usb_phy_generic");
367MODULE_AUTHOR("Texas Instruments Inc");
368MODULE_DESCRIPTION("NOP USB Transceiver driver");
369MODULE_LICENSE("GPL");
370

source code of linux/drivers/usb/phy/phy-generic.c