1// SPDX-License-Identifier: GPL-2.0
2/*
3 * MUSB OTG driver virtual root hub support
4 *
5 * Copyright 2005 Mentor Graphics Corporation
6 * Copyright (C) 2005-2006 by Texas Instruments
7 * Copyright (C) 2006-2007 Nokia Corporation
8 */
9
10#include <linux/module.h>
11#include <linux/kernel.h>
12#include <linux/sched.h>
13#include <linux/errno.h>
14#include <linux/time.h>
15#include <linux/timer.h>
16
17#include <asm/unaligned.h>
18
19#include "musb_core.h"
20
21void musb_host_finish_resume(struct work_struct *work)
22{
23 struct musb *musb;
24 unsigned long flags;
25 u8 power;
26
27 musb = container_of(work, struct musb, finish_resume_work.work);
28
29 spin_lock_irqsave(&musb->lock, flags);
30
31 power = musb_readb(musb->mregs, MUSB_POWER);
32 power &= ~MUSB_POWER_RESUME;
33 musb_dbg(musb, fmt: "root port resume stopped, power %02x", power);
34 musb_writeb(musb->mregs, MUSB_POWER, power);
35
36 /*
37 * ISSUE: DaVinci (RTL 1.300) disconnects after
38 * resume of high speed peripherals (but not full
39 * speed ones).
40 */
41 musb->is_active = 1;
42 musb->port1_status &= ~(USB_PORT_STAT_SUSPEND | MUSB_PORT_STAT_RESUME);
43 musb->port1_status |= USB_PORT_STAT_C_SUSPEND << 16;
44 usb_hcd_poll_rh_status(hcd: musb->hcd);
45 /* NOTE: it might really be A_WAIT_BCON ... */
46 musb_set_state(musb, otg_state: OTG_STATE_A_HOST);
47
48 spin_unlock_irqrestore(lock: &musb->lock, flags);
49}
50
51int musb_port_suspend(struct musb *musb, bool do_suspend)
52{
53 u8 power;
54 void __iomem *mbase = musb->mregs;
55
56 if (!is_host_active(musb))
57 return 0;
58
59 /* NOTE: this doesn't necessarily put PHY into low power mode,
60 * turning off its clock; that's a function of PHY integration and
61 * MUSB_POWER_ENSUSPEND. PHY may need a clock (sigh) to detect
62 * SE0 changing to connect (J) or wakeup (K) states.
63 */
64 power = musb_readb(mbase, MUSB_POWER);
65 if (do_suspend) {
66 int retries = 10000;
67
68 if (power & MUSB_POWER_RESUME)
69 return -EBUSY;
70
71 if (!(power & MUSB_POWER_SUSPENDM)) {
72 power |= MUSB_POWER_SUSPENDM;
73 musb_writeb(mbase, MUSB_POWER, power);
74
75 /* Needed for OPT A tests */
76 power = musb_readb(mbase, MUSB_POWER);
77 while (power & MUSB_POWER_SUSPENDM) {
78 power = musb_readb(mbase, MUSB_POWER);
79 if (retries-- < 1)
80 break;
81 }
82 }
83
84 musb_dbg(musb, fmt: "Root port suspended, power %02x", power);
85
86 musb->port1_status |= USB_PORT_STAT_SUSPEND;
87 switch (musb_get_state(musb)) {
88 case OTG_STATE_A_HOST:
89 musb_set_state(musb, otg_state: OTG_STATE_A_SUSPEND);
90 musb->is_active = musb->xceiv &&
91 musb->xceiv->otg->host->b_hnp_enable;
92 if (musb->is_active)
93 mod_timer(timer: &musb->otg_timer, expires: jiffies
94 + msecs_to_jiffies(
95 OTG_TIME_A_AIDL_BDIS));
96 musb_platform_try_idle(musb, timeout: 0);
97 break;
98 case OTG_STATE_B_HOST:
99 musb_set_state(musb, otg_state: OTG_STATE_B_WAIT_ACON);
100 musb->is_active = musb->xceiv &&
101 musb->xceiv->otg->host->b_hnp_enable;
102 musb_platform_try_idle(musb, timeout: 0);
103 break;
104 default:
105 musb_dbg(musb, fmt: "bogus rh suspend? %s",
106 musb_otg_state_string(musb));
107 }
108 } else if (power & MUSB_POWER_SUSPENDM) {
109 power &= ~MUSB_POWER_SUSPENDM;
110 power |= MUSB_POWER_RESUME;
111 musb_writeb(mbase, MUSB_POWER, power);
112
113 musb_dbg(musb, fmt: "Root port resuming, power %02x", power);
114
115 musb->port1_status |= MUSB_PORT_STAT_RESUME;
116 schedule_delayed_work(dwork: &musb->finish_resume_work,
117 delay: msecs_to_jiffies(USB_RESUME_TIMEOUT));
118 }
119 return 0;
120}
121
122void musb_port_reset(struct musb *musb, bool do_reset)
123{
124 u8 power;
125 void __iomem *mbase = musb->mregs;
126
127 if (musb_get_state(musb) == OTG_STATE_B_IDLE) {
128 musb_dbg(musb, fmt: "HNP: Returning from HNP; no hub reset from b_idle");
129 musb->port1_status &= ~USB_PORT_STAT_RESET;
130 return;
131 }
132
133 if (!is_host_active(musb))
134 return;
135
136 /* NOTE: caller guarantees it will turn off the reset when
137 * the appropriate amount of time has passed
138 */
139 power = musb_readb(mbase, MUSB_POWER);
140 if (do_reset) {
141 /*
142 * If RESUME is set, we must make sure it stays minimum 20 ms.
143 * Then we must clear RESUME and wait a bit to let musb start
144 * generating SOFs. If we don't do this, OPT HS A 6.8 tests
145 * fail with "Error! Did not receive an SOF before suspend
146 * detected".
147 */
148 if (power & MUSB_POWER_RESUME) {
149 long remain = (unsigned long) musb->rh_timer - jiffies;
150
151 if (musb->rh_timer > 0 && remain > 0) {
152 /* take into account the minimum delay after resume */
153 schedule_delayed_work(
154 dwork: &musb->deassert_reset_work, delay: remain);
155 return;
156 }
157
158 musb_writeb(mbase, MUSB_POWER,
159 power & ~MUSB_POWER_RESUME);
160
161 /* Give the core 1 ms to clear MUSB_POWER_RESUME */
162 schedule_delayed_work(dwork: &musb->deassert_reset_work,
163 delay: msecs_to_jiffies(m: 1));
164 return;
165 }
166
167 power &= 0xf0;
168 musb_writeb(mbase, MUSB_POWER,
169 power | MUSB_POWER_RESET);
170
171 musb->port1_status |= USB_PORT_STAT_RESET;
172 musb->port1_status &= ~USB_PORT_STAT_ENABLE;
173 schedule_delayed_work(dwork: &musb->deassert_reset_work,
174 delay: msecs_to_jiffies(m: 50));
175 } else {
176 musb_dbg(musb, fmt: "root port reset stopped");
177 musb_platform_pre_root_reset_end(musb);
178 musb_writeb(mbase, MUSB_POWER,
179 power & ~MUSB_POWER_RESET);
180 musb_platform_post_root_reset_end(musb);
181
182 power = musb_readb(mbase, MUSB_POWER);
183 if (power & MUSB_POWER_HSMODE) {
184 musb_dbg(musb, fmt: "high-speed device connected");
185 musb->port1_status |= USB_PORT_STAT_HIGH_SPEED;
186 }
187
188 musb->port1_status &= ~USB_PORT_STAT_RESET;
189 musb->port1_status |= USB_PORT_STAT_ENABLE
190 | (USB_PORT_STAT_C_RESET << 16)
191 | (USB_PORT_STAT_C_ENABLE << 16);
192 usb_hcd_poll_rh_status(hcd: musb->hcd);
193
194 musb->vbuserr_retry = VBUSERR_RETRY_COUNT;
195 }
196}
197
198void musb_root_disconnect(struct musb *musb)
199{
200 musb->port1_status = USB_PORT_STAT_POWER
201 | (USB_PORT_STAT_C_CONNECTION << 16);
202
203 usb_hcd_poll_rh_status(hcd: musb->hcd);
204 musb->is_active = 0;
205
206 switch (musb_get_state(musb)) {
207 case OTG_STATE_A_SUSPEND:
208 if (musb->xceiv && musb->xceiv->otg->host->b_hnp_enable) {
209 musb_set_state(musb, otg_state: OTG_STATE_A_PERIPHERAL);
210 musb->g.is_a_peripheral = 1;
211 break;
212 }
213 fallthrough;
214 case OTG_STATE_A_HOST:
215 musb_set_state(musb, otg_state: OTG_STATE_A_WAIT_BCON);
216 musb->is_active = 0;
217 break;
218 case OTG_STATE_A_WAIT_VFALL:
219 musb_set_state(musb, otg_state: OTG_STATE_B_IDLE);
220 break;
221 default:
222 musb_dbg(musb, fmt: "host disconnect (%s)",
223 musb_otg_state_string(musb));
224 }
225}
226EXPORT_SYMBOL_GPL(musb_root_disconnect);
227
228
229/*---------------------------------------------------------------------*/
230
231/* Caller may or may not hold musb->lock */
232int musb_hub_status_data(struct usb_hcd *hcd, char *buf)
233{
234 struct musb *musb = hcd_to_musb(hcd);
235 int retval = 0;
236
237 /* called in_irq() via usb_hcd_poll_rh_status() */
238 if (musb->port1_status & 0xffff0000) {
239 *buf = 0x02;
240 retval = 1;
241 }
242 return retval;
243}
244
245static int musb_has_gadget(struct musb *musb)
246{
247 /*
248 * In host-only mode we start a connection right away. In OTG mode
249 * we have to wait until we loaded a gadget. We don't really need a
250 * gadget if we operate as a host but we should not start a session
251 * as a device without a gadget or else we explode.
252 */
253#ifdef CONFIG_USB_MUSB_HOST
254 return 1;
255#else
256 return musb->port_mode == MUSB_HOST;
257#endif
258}
259
260int musb_hub_control(
261 struct usb_hcd *hcd,
262 u16 typeReq,
263 u16 wValue,
264 u16 wIndex,
265 char *buf,
266 u16 wLength)
267{
268 struct musb *musb = hcd_to_musb(hcd);
269 u32 temp;
270 int retval = 0;
271 unsigned long flags;
272 bool start_musb = false;
273
274 spin_lock_irqsave(&musb->lock, flags);
275
276 if (unlikely(!HCD_HW_ACCESSIBLE(hcd))) {
277 spin_unlock_irqrestore(lock: &musb->lock, flags);
278 return -ESHUTDOWN;
279 }
280
281 /* hub features: always zero, setting is a NOP
282 * port features: reported, sometimes updated when host is active
283 * no indicators
284 */
285 switch (typeReq) {
286 case ClearHubFeature:
287 case SetHubFeature:
288 switch (wValue) {
289 case C_HUB_OVER_CURRENT:
290 case C_HUB_LOCAL_POWER:
291 break;
292 default:
293 goto error;
294 }
295 break;
296 case ClearPortFeature:
297 if ((wIndex & 0xff) != 1)
298 goto error;
299
300 switch (wValue) {
301 case USB_PORT_FEAT_ENABLE:
302 break;
303 case USB_PORT_FEAT_SUSPEND:
304 musb_port_suspend(musb, do_suspend: false);
305 break;
306 case USB_PORT_FEAT_POWER:
307 if (!hcd->self.is_b_host)
308 musb_platform_set_vbus(musb, is_on: 0);
309 break;
310 case USB_PORT_FEAT_C_CONNECTION:
311 case USB_PORT_FEAT_C_ENABLE:
312 case USB_PORT_FEAT_C_OVER_CURRENT:
313 case USB_PORT_FEAT_C_RESET:
314 case USB_PORT_FEAT_C_SUSPEND:
315 break;
316 default:
317 goto error;
318 }
319 musb_dbg(musb, fmt: "clear feature %d", wValue);
320 musb->port1_status &= ~(1 << wValue);
321 break;
322 case GetHubDescriptor:
323 {
324 struct usb_hub_descriptor *desc = (void *)buf;
325
326 desc->bDescLength = 9;
327 desc->bDescriptorType = USB_DT_HUB;
328 desc->bNbrPorts = 1;
329 desc->wHubCharacteristics = cpu_to_le16(
330 HUB_CHAR_INDV_PORT_LPSM /* per-port power switching */
331 | HUB_CHAR_NO_OCPM /* no overcurrent reporting */
332 );
333 desc->bPwrOn2PwrGood = 5; /* msec/2 */
334 desc->bHubContrCurrent = 0;
335
336 /* workaround bogus struct definition */
337 desc->u.hs.DeviceRemovable[0] = 0x02; /* port 1 */
338 desc->u.hs.DeviceRemovable[1] = 0xff;
339 }
340 break;
341 case GetHubStatus:
342 temp = 0;
343 *(__le32 *) buf = cpu_to_le32(temp);
344 break;
345 case GetPortStatus:
346 if (wIndex != 1)
347 goto error;
348
349 put_unaligned(cpu_to_le32(musb->port1_status
350 & ~MUSB_PORT_STAT_RESUME),
351 (__le32 *) buf);
352
353 /* port change status is more interesting */
354 musb_dbg(musb, fmt: "port status %08x", musb->port1_status);
355 break;
356 case SetPortFeature:
357 if ((wIndex & 0xff) != 1)
358 goto error;
359
360 switch (wValue) {
361 case USB_PORT_FEAT_POWER:
362 /* NOTE: this controller has a strange state machine
363 * that involves "requesting sessions" according to
364 * magic side effects from incompletely-described
365 * rules about startup...
366 *
367 * This call is what really starts the host mode; be
368 * very careful about side effects if you reorder any
369 * initialization logic, e.g. for OTG, or change any
370 * logic relating to VBUS power-up.
371 */
372 if (!hcd->self.is_b_host && musb_has_gadget(musb))
373 start_musb = true;
374 break;
375 case USB_PORT_FEAT_RESET:
376 musb_port_reset(musb, do_reset: true);
377 break;
378 case USB_PORT_FEAT_SUSPEND:
379 musb_port_suspend(musb, do_suspend: true);
380 break;
381 case USB_PORT_FEAT_TEST:
382 if (unlikely(is_host_active(musb)))
383 goto error;
384
385 wIndex >>= 8;
386 switch (wIndex) {
387 case USB_TEST_J:
388 pr_debug("USB_TEST_J\n");
389 temp = MUSB_TEST_J;
390 break;
391 case USB_TEST_K:
392 pr_debug("USB_TEST_K\n");
393 temp = MUSB_TEST_K;
394 break;
395 case USB_TEST_SE0_NAK:
396 pr_debug("USB_TEST_SE0_NAK\n");
397 temp = MUSB_TEST_SE0_NAK;
398 break;
399 case USB_TEST_PACKET:
400 pr_debug("USB_TEST_PACKET\n");
401 temp = MUSB_TEST_PACKET;
402 musb_load_testpacket(musb);
403 break;
404 case USB_TEST_FORCE_ENABLE:
405 pr_debug("USB_TEST_FORCE_ENABLE\n");
406 temp = MUSB_TEST_FORCE_HOST
407 | MUSB_TEST_FORCE_HS;
408
409 musb_writeb(musb->mregs, MUSB_DEVCTL,
410 MUSB_DEVCTL_SESSION);
411 break;
412 case 6:
413 pr_debug("TEST_FIFO_ACCESS\n");
414 temp = MUSB_TEST_FIFO_ACCESS;
415 break;
416 default:
417 goto error;
418 }
419 musb_writeb(musb->mregs, MUSB_TESTMODE, temp);
420 break;
421 default:
422 goto error;
423 }
424 musb_dbg(musb, fmt: "set feature %d", wValue);
425 musb->port1_status |= 1 << wValue;
426 break;
427
428 default:
429error:
430 /* "protocol stall" on error */
431 retval = -EPIPE;
432 }
433 spin_unlock_irqrestore(lock: &musb->lock, flags);
434
435 if (start_musb)
436 musb_start(musb);
437
438 return retval;
439}
440

source code of linux/drivers/usb/musb/musb_virthub.c