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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Cadence USBSS and USBSSP DRD Driver.
4 *
5 * Copyright (C) 2018-2019 Cadence.
6 * Copyright (C) 2017-2018 NXP
7 * Copyright (C) 2019 Texas Instruments
8 *
9 * Author: Peter Chen <peter.chen@nxp.com>
10 * Pawel Laszczak <pawell@cadence.com>
11 * Roger Quadros <rogerq@ti.com>
12 */
13
14#include <linux/dma-mapping.h>
15#include <linux/module.h>
16#include <linux/kernel.h>
17#include <linux/platform_device.h>
18#include <linux/interrupt.h>
19#include <linux/io.h>
20#include <linux/pm_runtime.h>
21
22#include "core.h"
23#include "host-export.h"
24#include "drd.h"
25
26static int cdns_idle_init(struct cdns *cdns);
27
28static int cdns_role_start(struct cdns *cdns, enum usb_role role)
29{
30 int ret;
31
32 if (WARN_ON(role > USB_ROLE_DEVICE))
33 return 0;
34
35 mutex_lock(&cdns->mutex);
36 cdns->role = role;
37 mutex_unlock(&cdns->mutex);
38
39 if (!cdns->roles[role])
40 return -ENXIO;
41
42 if (cdns->roles[role]->state == CDNS_ROLE_STATE_ACTIVE)
43 return 0;
44
45 mutex_lock(&cdns->mutex);
46 ret = cdns->roles[role]->start(cdns);
47 if (!ret)
48 cdns->roles[role]->state = CDNS_ROLE_STATE_ACTIVE;
49 mutex_unlock(&cdns->mutex);
50
51 return ret;
52}
53
54static void cdns_role_stop(struct cdns *cdns)
55{
56 enum usb_role role = cdns->role;
57
58 if (WARN_ON(role > USB_ROLE_DEVICE))
59 return;
60
61 if (cdns->roles[role]->state == CDNS_ROLE_STATE_INACTIVE)
62 return;
63
64 mutex_lock(&cdns->mutex);
65 cdns->roles[role]->stop(cdns);
66 cdns->roles[role]->state = CDNS_ROLE_STATE_INACTIVE;
67 mutex_unlock(&cdns->mutex);
68}
69
70static void cdns_exit_roles(struct cdns *cdns)
71{
72 cdns_role_stop(cdns);
73 cdns_drd_exit(cdns);
74}
75
76/**
77 * cdns_core_init_role - initialize role of operation
78 * @cdns: Pointer to cdns structure
79 *
80 * Returns 0 on success otherwise negative errno
81 */
82static int cdns_core_init_role(struct cdns *cdns)
83{
84 struct device *dev = cdns->dev;
85 enum usb_dr_mode best_dr_mode;
86 enum usb_dr_mode dr_mode;
87 int ret;
88
89 dr_mode = usb_get_dr_mode(dev);
90 cdns->role = USB_ROLE_NONE;
91
92 /*
93 * If driver can't read mode by means of usb_get_dr_mode function then
94 * chooses mode according with Kernel configuration. This setting
95 * can be restricted later depending on strap pin configuration.
96 */
97 if (dr_mode == USB_DR_MODE_UNKNOWN) {
98 if (cdns->version == CDNSP_CONTROLLER_V2) {
99 if (IS_ENABLED(CONFIG_USB_CDNSP_HOST) &&
100 IS_ENABLED(CONFIG_USB_CDNSP_GADGET))
101 dr_mode = USB_DR_MODE_OTG;
102 else if (IS_ENABLED(CONFIG_USB_CDNSP_HOST))
103 dr_mode = USB_DR_MODE_HOST;
104 else if (IS_ENABLED(CONFIG_USB_CDNSP_GADGET))
105 dr_mode = USB_DR_MODE_PERIPHERAL;
106 } else {
107 if (IS_ENABLED(CONFIG_USB_CDNS3_HOST) &&
108 IS_ENABLED(CONFIG_USB_CDNS3_GADGET))
109 dr_mode = USB_DR_MODE_OTG;
110 else if (IS_ENABLED(CONFIG_USB_CDNS3_HOST))
111 dr_mode = USB_DR_MODE_HOST;
112 else if (IS_ENABLED(CONFIG_USB_CDNS3_GADGET))
113 dr_mode = USB_DR_MODE_PERIPHERAL;
114 }
115 }
116
117 /*
118 * At this point cdns->dr_mode contains strap configuration.
119 * Driver try update this setting considering kernel configuration
120 */
121 best_dr_mode = cdns->dr_mode;
122
123 ret = cdns_idle_init(cdns);
124 if (ret)
125 return ret;
126
127 if (dr_mode == USB_DR_MODE_OTG) {
128 best_dr_mode = cdns->dr_mode;
129 } else if (cdns->dr_mode == USB_DR_MODE_OTG) {
130 best_dr_mode = dr_mode;
131 } else if (cdns->dr_mode != dr_mode) {
132 dev_err(dev, "Incorrect DRD configuration\n");
133 return -EINVAL;
134 }
135
136 dr_mode = best_dr_mode;
137
138 if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_HOST) {
139 if ((cdns->version == CDNSP_CONTROLLER_V2 &&
140 IS_ENABLED(CONFIG_USB_CDNSP_HOST)) ||
141 (cdns->version < CDNSP_CONTROLLER_V2 &&
142 IS_ENABLED(CONFIG_USB_CDNS3_HOST)))
143 ret = cdns_host_init(cdns);
144 else
145 ret = -ENXIO;
146
147 if (ret) {
148 dev_err(dev, "Host initialization failed with %d\n",
149 ret);
150 goto err;
151 }
152 }
153
154 if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_PERIPHERAL) {
155 if (cdns->gadget_init)
156 ret = cdns->gadget_init(cdns);
157 else
158 ret = -ENXIO;
159
160 if (ret) {
161 dev_err(dev, "Device initialization failed with %d\n",
162 ret);
163 goto err;
164 }
165 }
166
167 cdns->dr_mode = dr_mode;
168
169 ret = cdns_drd_update_mode(cdns);
170 if (ret)
171 goto err;
172
173 /* Initialize idle role to start with */
174 ret = cdns_role_start(cdns, USB_ROLE_NONE);
175 if (ret)
176 goto err;
177
178 switch (cdns->dr_mode) {
179 case USB_DR_MODE_OTG:
180 ret = cdns_hw_role_switch(cdns);
181 if (ret)
182 goto err;
183 break;
184 case USB_DR_MODE_PERIPHERAL:
185 ret = cdns_role_start(cdns, USB_ROLE_DEVICE);
186 if (ret)
187 goto err;
188 break;
189 case USB_DR_MODE_HOST:
190 ret = cdns_role_start(cdns, USB_ROLE_HOST);
191 if (ret)
192 goto err;
193 break;
194 default:
195 ret = -EINVAL;
196 goto err;
197 }
198
199 return 0;
200err:
201 cdns_exit_roles(cdns);
202 return ret;
203}
204
205/**
206 * cdns_hw_role_state_machine - role switch state machine based on hw events.
207 * @cdns: Pointer to controller structure.
208 *
209 * Returns next role to be entered based on hw events.
210 */
211static enum usb_role cdns_hw_role_state_machine(struct cdns *cdns)
212{
213 enum usb_role role = USB_ROLE_NONE;
214 int id, vbus;
215
216 if (cdns->dr_mode != USB_DR_MODE_OTG) {
217 if (cdns_is_host(cdns))
218 role = USB_ROLE_HOST;
219 if (cdns_is_device(cdns))
220 role = USB_ROLE_DEVICE;
221
222 return role;
223 }
224
225 id = cdns_get_id(cdns);
226 vbus = cdns_get_vbus(cdns);
227
228 /*
229 * Role change state machine
230 * Inputs: ID, VBUS
231 * Previous state: cdns->role
232 * Next state: role
233 */
234 role = cdns->role;
235
236 switch (role) {
237 case USB_ROLE_NONE:
238 /*
239 * Driver treats USB_ROLE_NONE synonymous to IDLE state from
240 * controller specification.
241 */
242 if (!id)
243 role = USB_ROLE_HOST;
244 else if (vbus)
245 role = USB_ROLE_DEVICE;
246 break;
247 case USB_ROLE_HOST: /* from HOST, we can only change to NONE */
248 if (id)
249 role = USB_ROLE_NONE;
250 break;
251 case USB_ROLE_DEVICE: /* from GADGET, we can only change to NONE*/
252 if (!vbus)
253 role = USB_ROLE_NONE;
254 break;
255 }
256
257 dev_dbg(cdns->dev, "role %d -> %d\n", cdns->role, role);
258
259 return role;
260}
261
262static int cdns_idle_role_start(struct cdns *cdns)
263{
264 return 0;
265}
266
267static void cdns_idle_role_stop(struct cdns *cdns)
268{
269 /* Program Lane swap and bring PHY out of RESET */
270 phy_reset(cdns->usb3_phy);
271}
272
273static int cdns_idle_init(struct cdns *cdns)
274{
275 struct cdns_role_driver *rdrv;
276
277 rdrv = devm_kzalloc(cdns->dev, sizeof(*rdrv), GFP_KERNEL);
278 if (!rdrv)
279 return -ENOMEM;
280
281 rdrv->start = cdns_idle_role_start;
282 rdrv->stop = cdns_idle_role_stop;
283 rdrv->state = CDNS_ROLE_STATE_INACTIVE;
284 rdrv->suspend = NULL;
285 rdrv->resume = NULL;
286 rdrv->name = "idle";
287
288 cdns->roles[USB_ROLE_NONE] = rdrv;
289
290 return 0;
291}
292
293/**
294 * cdns_hw_role_switch - switch roles based on HW state
295 * @cdns: controller
296 */
297int cdns_hw_role_switch(struct cdns *cdns)
298{
299 enum usb_role real_role, current_role;
300 int ret = 0;
301
302 /* Depends on role switch class */
303 if (cdns->role_sw)
304 return 0;
305
306 pm_runtime_get_sync(cdns->dev);
307
308 current_role = cdns->role;
309 real_role = cdns_hw_role_state_machine(cdns);
310
311 /* Do nothing if nothing changed */
312 if (current_role == real_role)
313 goto exit;
314
315 cdns_role_stop(cdns);
316
317 dev_dbg(cdns->dev, "Switching role %d -> %d", current_role, real_role);
318
319 ret = cdns_role_start(cdns, real_role);
320 if (ret) {
321 /* Back to current role */
322 dev_err(cdns->dev, "set %d has failed, back to %d\n",
323 real_role, current_role);
324 ret = cdns_role_start(cdns, current_role);
325 if (ret)
326 dev_err(cdns->dev, "back to %d failed too\n",
327 current_role);
328 }
329exit:
330 pm_runtime_put_sync(cdns->dev);
331 return ret;
332}
333
334/**
335 * cdns_role_get - get current role of controller.
336 *
337 * @sw: pointer to USB role switch structure
338 *
339 * Returns role
340 */
341static enum usb_role cdns_role_get(struct usb_role_switch *sw)
342{
343 struct cdns *cdns = usb_role_switch_get_drvdata(sw);
344
345 return cdns->role;
346}
347
348/**
349 * cdns_role_set - set current role of controller.
350 *
351 * @sw: pointer to USB role switch structure
352 * @role: the previous role
353 * Handles below events:
354 * - Role switch for dual-role devices
355 * - USB_ROLE_GADGET <--> USB_ROLE_NONE for peripheral-only devices
356 */
357static int cdns_role_set(struct usb_role_switch *sw, enum usb_role role)
358{
359 struct cdns *cdns = usb_role_switch_get_drvdata(sw);
360 int ret = 0;
361
362 pm_runtime_get_sync(cdns->dev);
363
364 if (cdns->role == role)
365 goto pm_put;
366
367 if (cdns->dr_mode == USB_DR_MODE_HOST) {
368 switch (role) {
369 case USB_ROLE_NONE:
370 case USB_ROLE_HOST:
371 break;
372 default:
373 goto pm_put;
374 }
375 }
376
377 if (cdns->dr_mode == USB_DR_MODE_PERIPHERAL) {
378 switch (role) {
379 case USB_ROLE_NONE:
380 case USB_ROLE_DEVICE:
381 break;
382 default:
383 goto pm_put;
384 }
385 }
386
387 cdns_role_stop(cdns);
388 ret = cdns_role_start(cdns, role);
389 if (ret)
390 dev_err(cdns->dev, "set role %d has failed\n", role);
391
392pm_put:
393 pm_runtime_put_sync(cdns->dev);
394 return ret;
395}
396
397
398/**
399 * cdns_wakeup_irq - interrupt handler for wakeup events
400 * @irq: irq number for cdns3/cdnsp core device
401 * @data: structure of cdns
402 *
403 * Returns IRQ_HANDLED or IRQ_NONE
404 */
405static irqreturn_t cdns_wakeup_irq(int irq, void *data)
406{
407 struct cdns *cdns = data;
408
409 if (cdns->in_lpm) {
410 disable_irq_nosync(irq);
411 cdns->wakeup_pending = true;
412 if ((cdns->role == USB_ROLE_HOST) && cdns->host_dev)
413 pm_request_resume(&cdns->host_dev->dev);
414
415 return IRQ_HANDLED;
416 }
417
418 return IRQ_NONE;
419}
420
421/**
422 * cdns_init - probe for cdns3/cdnsp core device
423 * @cdns: Pointer to cdns structure.
424 *
425 * Returns 0 on success otherwise negative errno
426 */
427int cdns_init(struct cdns *cdns)
428{
429 struct device *dev = cdns->dev;
430 int ret;
431
432 ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
433 if (ret) {
434 dev_err(dev, "error setting dma mask: %d\n", ret);
435 return ret;
436 }
437
438 mutex_init(&cdns->mutex);
439
440 if (device_property_read_bool(dev, "usb-role-switch")) {
441 struct usb_role_switch_desc sw_desc = { };
442
443 sw_desc.set = cdns_role_set;
444 sw_desc.get = cdns_role_get;
445 sw_desc.allow_userspace_control = true;
446 sw_desc.driver_data = cdns;
447 sw_desc.fwnode = dev->fwnode;
448
449 cdns->role_sw = usb_role_switch_register(dev, &sw_desc);
450 if (IS_ERR(cdns->role_sw)) {
451 dev_warn(dev, "Unable to register Role Switch\n");
452 return PTR_ERR(cdns->role_sw);
453 }
454 }
455
456 if (cdns->wakeup_irq) {
457 ret = devm_request_irq(cdns->dev, cdns->wakeup_irq,
458 cdns_wakeup_irq,
459 IRQF_SHARED,
460 dev_name(cdns->dev), cdns);
461
462 if (ret) {
463 dev_err(cdns->dev, "couldn't register wakeup irq handler\n");
464 goto role_switch_unregister;
465 }
466 }
467
468 ret = cdns_drd_init(cdns);
469 if (ret)
470 goto init_failed;
471
472 ret = cdns_core_init_role(cdns);
473 if (ret)
474 goto init_failed;
475
476 spin_lock_init(&cdns->lock);
477
478 dev_dbg(dev, "Cadence USB3 core: probe succeed\n");
479
480 return 0;
481init_failed:
482 cdns_drd_exit(cdns);
483role_switch_unregister:
484 if (cdns->role_sw)
485 usb_role_switch_unregister(cdns->role_sw);
486
487 return ret;
488}
489EXPORT_SYMBOL_GPL(cdns_init);
490
491/**
492 * cdns_remove - unbind drd driver and clean up
493 * @cdns: Pointer to cdns structure.
494 *
495 * Returns 0 on success otherwise negative errno
496 */
497int cdns_remove(struct cdns *cdns)
498{
499 cdns_exit_roles(cdns);
500 usb_role_switch_unregister(cdns->role_sw);
501
502 return 0;
503}
504EXPORT_SYMBOL_GPL(cdns_remove);
505
506#ifdef CONFIG_PM_SLEEP
507int cdns_suspend(struct cdns *cdns)
508{
509 struct device *dev = cdns->dev;
510 unsigned long flags;
511
512 if (pm_runtime_status_suspended(dev))
513 pm_runtime_resume(dev);
514
515 if (cdns->roles[cdns->role]->suspend) {
516 spin_lock_irqsave(&cdns->lock, flags);
517 cdns->roles[cdns->role]->suspend(cdns, false);
518 spin_unlock_irqrestore(&cdns->lock, flags);
519 }
520
521 return 0;
522}
523EXPORT_SYMBOL_GPL(cdns_suspend);
524
525int cdns_resume(struct cdns *cdns, u8 set_active)
526{
527 struct device *dev = cdns->dev;
528 enum usb_role real_role;
529 bool role_changed = false;
530 int ret = 0;
531
532 if (cdns_power_is_lost(cdns)) {
533 if (cdns->role_sw) {
534 cdns->role = cdns_role_get(cdns->role_sw);
535 } else {
536 real_role = cdns_hw_role_state_machine(cdns);
537 if (real_role != cdns->role) {
538 ret = cdns_hw_role_switch(cdns);
539 if (ret)
540 return ret;
541 role_changed = true;
542 }
543 }
544
545 if (!role_changed) {
546 if (cdns->role == USB_ROLE_HOST)
547 ret = cdns_drd_host_on(cdns);
548 else if (cdns->role == USB_ROLE_DEVICE)
549 ret = cdns_drd_gadget_on(cdns);
550
551 if (ret)
552 return ret;
553 }
554 }
555
556 if (cdns->roles[cdns->role]->resume)
557 cdns->roles[cdns->role]->resume(cdns, cdns_power_is_lost(cdns));
558
559 if (set_active) {
560 pm_runtime_disable(dev);
561 pm_runtime_set_active(dev);
562 pm_runtime_enable(dev);
563 }
564
565 return 0;
566}
567EXPORT_SYMBOL_GPL(cdns_resume);
568#endif /* CONFIG_PM_SLEEP */
569
570MODULE_AUTHOR("Peter Chen <peter.chen@nxp.com>");
571MODULE_AUTHOR("Pawel Laszczak <pawell@cadence.com>");
572MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");
573MODULE_DESCRIPTION("Cadence USBSS and USBSSP DRD Driver");
574MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Cadence USBSS DRD Driver.
4 *
5 * Copyright (C) 2018-2019 Cadence.
6 * Copyright (C) 2017-2018 NXP
7 * Copyright (C) 2019 Texas Instruments
8 *
9 * Author: Peter Chen <peter.chen@nxp.com>
10 * Pawel Laszczak <pawell@cadence.com>
11 * Roger Quadros <rogerq@ti.com>
12 */
13
14#include <linux/dma-mapping.h>
15#include <linux/module.h>
16#include <linux/kernel.h>
17#include <linux/platform_device.h>
18#include <linux/interrupt.h>
19#include <linux/io.h>
20#include <linux/pm_runtime.h>
21
22#include "gadget.h"
23#include "core.h"
24#include "host-export.h"
25#include "gadget-export.h"
26#include "drd.h"
27
28static int cdns3_idle_init(struct cdns3 *cdns);
29
30static inline
31struct cdns3_role_driver *cdns3_get_current_role_driver(struct cdns3 *cdns)
32{
33 WARN_ON(!cdns->roles[cdns->role]);
34 return cdns->roles[cdns->role];
35}
36
37static int cdns3_role_start(struct cdns3 *cdns, enum usb_role role)
38{
39 int ret;
40
41 if (WARN_ON(role > USB_ROLE_DEVICE))
42 return 0;
43
44 mutex_lock(&cdns->mutex);
45 cdns->role = role;
46 mutex_unlock(&cdns->mutex);
47
48 if (!cdns->roles[role])
49 return -ENXIO;
50
51 if (cdns->roles[role]->state == CDNS3_ROLE_STATE_ACTIVE)
52 return 0;
53
54 mutex_lock(&cdns->mutex);
55 ret = cdns->roles[role]->start(cdns);
56 if (!ret)
57 cdns->roles[role]->state = CDNS3_ROLE_STATE_ACTIVE;
58 mutex_unlock(&cdns->mutex);
59
60 return ret;
61}
62
63static void cdns3_role_stop(struct cdns3 *cdns)
64{
65 enum usb_role role = cdns->role;
66
67 if (WARN_ON(role > USB_ROLE_DEVICE))
68 return;
69
70 if (cdns->roles[role]->state == CDNS3_ROLE_STATE_INACTIVE)
71 return;
72
73 mutex_lock(&cdns->mutex);
74 cdns->roles[role]->stop(cdns);
75 cdns->roles[role]->state = CDNS3_ROLE_STATE_INACTIVE;
76 mutex_unlock(&cdns->mutex);
77}
78
79static void cdns3_exit_roles(struct cdns3 *cdns)
80{
81 cdns3_role_stop(cdns);
82 cdns3_drd_exit(cdns);
83}
84
85static enum usb_role cdsn3_hw_role_state_machine(struct cdns3 *cdns);
86
87/**
88 * cdns3_core_init_role - initialize role of operation
89 * @cdns: Pointer to cdns3 structure
90 *
91 * Returns 0 on success otherwise negative errno
92 */
93static int cdns3_core_init_role(struct cdns3 *cdns)
94{
95 struct device *dev = cdns->dev;
96 enum usb_dr_mode best_dr_mode;
97 enum usb_dr_mode dr_mode;
98 int ret = 0;
99
100 dr_mode = usb_get_dr_mode(dev);
101 cdns->role = USB_ROLE_NONE;
102
103 /*
104 * If driver can't read mode by means of usb_get_dr_mode function then
105 * chooses mode according with Kernel configuration. This setting
106 * can be restricted later depending on strap pin configuration.
107 */
108 if (dr_mode == USB_DR_MODE_UNKNOWN) {
109 if (IS_ENABLED(CONFIG_USB_CDNS3_HOST) &&
110 IS_ENABLED(CONFIG_USB_CDNS3_GADGET))
111 dr_mode = USB_DR_MODE_OTG;
112 else if (IS_ENABLED(CONFIG_USB_CDNS3_HOST))
113 dr_mode = USB_DR_MODE_HOST;
114 else if (IS_ENABLED(CONFIG_USB_CDNS3_GADGET))
115 dr_mode = USB_DR_MODE_PERIPHERAL;
116 }
117
118 /*
119 * At this point cdns->dr_mode contains strap configuration.
120 * Driver try update this setting considering kernel configuration
121 */
122 best_dr_mode = cdns->dr_mode;
123
124 ret = cdns3_idle_init(cdns);
125 if (ret)
126 return ret;
127
128 if (dr_mode == USB_DR_MODE_OTG) {
129 best_dr_mode = cdns->dr_mode;
130 } else if (cdns->dr_mode == USB_DR_MODE_OTG) {
131 best_dr_mode = dr_mode;
132 } else if (cdns->dr_mode != dr_mode) {
133 dev_err(dev, "Incorrect DRD configuration\n");
134 return -EINVAL;
135 }
136
137 dr_mode = best_dr_mode;
138
139 if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_HOST) {
140 ret = cdns3_host_init(cdns);
141 if (ret) {
142 dev_err(dev, "Host initialization failed with %d\n",
143 ret);
144 goto err;
145 }
146 }
147
148 if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_PERIPHERAL) {
149 ret = cdns3_gadget_init(cdns);
150 if (ret) {
151 dev_err(dev, "Device initialization failed with %d\n",
152 ret);
153 goto err;
154 }
155 }
156
157 cdns->dr_mode = dr_mode;
158
159 ret = cdns3_drd_update_mode(cdns);
160 if (ret)
161 goto err;
162
163 /* Initialize idle role to start with */
164 ret = cdns3_role_start(cdns, USB_ROLE_NONE);
165 if (ret)
166 goto err;
167
168 switch (cdns->dr_mode) {
169 case USB_DR_MODE_OTG:
170 ret = cdns3_hw_role_switch(cdns);
171 if (ret)
172 goto err;
173 break;
174 case USB_DR_MODE_PERIPHERAL:
175 ret = cdns3_role_start(cdns, USB_ROLE_DEVICE);
176 if (ret)
177 goto err;
178 break;
179 case USB_DR_MODE_HOST:
180 ret = cdns3_role_start(cdns, USB_ROLE_HOST);
181 if (ret)
182 goto err;
183 break;
184 default:
185 ret = -EINVAL;
186 goto err;
187 }
188
189 return ret;
190err:
191 cdns3_exit_roles(cdns);
192 return ret;
193}
194
195/**
196 * cdsn3_hw_role_state_machine - role switch state machine based on hw events.
197 * @cdns: Pointer to controller structure.
198 *
199 * Returns next role to be entered based on hw events.
200 */
201static enum usb_role cdsn3_hw_role_state_machine(struct cdns3 *cdns)
202{
203 enum usb_role role;
204 int id, vbus;
205
206 if (cdns->dr_mode != USB_DR_MODE_OTG)
207 goto not_otg;
208
209 id = cdns3_get_id(cdns);
210 vbus = cdns3_get_vbus(cdns);
211
212 /*
213 * Role change state machine
214 * Inputs: ID, VBUS
215 * Previous state: cdns->role
216 * Next state: role
217 */
218 role = cdns->role;
219
220 switch (role) {
221 case USB_ROLE_NONE:
222 /*
223 * Driver treats USB_ROLE_NONE synonymous to IDLE state from
224 * controller specification.
225 */
226 if (!id)
227 role = USB_ROLE_HOST;
228 else if (vbus)
229 role = USB_ROLE_DEVICE;
230 break;
231 case USB_ROLE_HOST: /* from HOST, we can only change to NONE */
232 if (id)
233 role = USB_ROLE_NONE;
234 break;
235 case USB_ROLE_DEVICE: /* from GADGET, we can only change to NONE*/
236 if (!vbus)
237 role = USB_ROLE_NONE;
238 break;
239 }
240
241 dev_dbg(cdns->dev, "role %d -> %d\n", cdns->role, role);
242
243 return role;
244
245not_otg:
246 if (cdns3_is_host(cdns))
247 role = USB_ROLE_HOST;
248 if (cdns3_is_device(cdns))
249 role = USB_ROLE_DEVICE;
250
251 return role;
252}
253
254static int cdns3_idle_role_start(struct cdns3 *cdns)
255{
256 return 0;
257}
258
259static void cdns3_idle_role_stop(struct cdns3 *cdns)
260{
261 /* Program Lane swap and bring PHY out of RESET */
262 phy_reset(cdns->usb3_phy);
263}
264
265static int cdns3_idle_init(struct cdns3 *cdns)
266{
267 struct cdns3_role_driver *rdrv;
268
269 rdrv = devm_kzalloc(cdns->dev, sizeof(*rdrv), GFP_KERNEL);
270 if (!rdrv)
271 return -ENOMEM;
272
273 rdrv->start = cdns3_idle_role_start;
274 rdrv->stop = cdns3_idle_role_stop;
275 rdrv->state = CDNS3_ROLE_STATE_INACTIVE;
276 rdrv->suspend = NULL;
277 rdrv->resume = NULL;
278 rdrv->name = "idle";
279
280 cdns->roles[USB_ROLE_NONE] = rdrv;
281
282 return 0;
283}
284
285/**
286 * cdns3_hw_role_switch - switch roles based on HW state
287 * @cdns3: controller
288 */
289int cdns3_hw_role_switch(struct cdns3 *cdns)
290{
291 enum usb_role real_role, current_role;
292 int ret = 0;
293
294 /* Do nothing if role based on syfs. */
295 if (cdns->role_override)
296 return 0;
297
298 pm_runtime_get_sync(cdns->dev);
299
300 current_role = cdns->role;
301 real_role = cdsn3_hw_role_state_machine(cdns);
302
303 /* Do nothing if nothing changed */
304 if (current_role == real_role)
305 goto exit;
306
307 cdns3_role_stop(cdns);
308
309 dev_dbg(cdns->dev, "Switching role %d -> %d", current_role, real_role);
310
311 ret = cdns3_role_start(cdns, real_role);
312 if (ret) {
313 /* Back to current role */
314 dev_err(cdns->dev, "set %d has failed, back to %d\n",
315 real_role, current_role);
316 ret = cdns3_role_start(cdns, current_role);
317 if (ret)
318 dev_err(cdns->dev, "back to %d failed too\n",
319 current_role);
320 }
321exit:
322 pm_runtime_put_sync(cdns->dev);
323 return ret;
324}
325
326/**
327 * cdsn3_role_get - get current role of controller.
328 *
329 * @dev: Pointer to device structure
330 *
331 * Returns role
332 */
333static enum usb_role cdns3_role_get(struct device *dev)
334{
335 struct cdns3 *cdns = dev_get_drvdata(dev);
336
337 return cdns->role;
338}
339
340/**
341 * cdns3_role_set - set current role of controller.
342 *
343 * @dev: pointer to device object
344 * @role - the previous role
345 * Handles below events:
346 * - Role switch for dual-role devices
347 * - USB_ROLE_GADGET <--> USB_ROLE_NONE for peripheral-only devices
348 */
349static int cdns3_role_set(struct device *dev, enum usb_role role)
350{
351 struct cdns3 *cdns = dev_get_drvdata(dev);
352 int ret = 0;
353
354 pm_runtime_get_sync(cdns->dev);
355
356 /*
357 * FIXME: switch role framework should be extended to meet
358 * requirements. Driver assumes that role can be controlled
359 * by SW or HW. Temporary workaround is to use USB_ROLE_NONE to
360 * switch from SW to HW control.
361 *
362 * For dr_mode == USB_DR_MODE_OTG:
363 * if user sets USB_ROLE_HOST or USB_ROLE_DEVICE then driver
364 * sets role_override flag and forces that role.
365 * if user sets USB_ROLE_NONE, driver clears role_override and lets
366 * HW state machine take over.
367 *
368 * For dr_mode != USB_DR_MODE_OTG:
369 * Assumptions:
370 * 1. Restricted user control between NONE and dr_mode.
371 * 2. Driver doesn't need to rely on role_override flag.
372 * 3. Driver needs to ensure that HW state machine is never called
373 * if dr_mode != USB_DR_MODE_OTG.
374 */
375 if (role == USB_ROLE_NONE)
376 cdns->role_override = 0;
377 else
378 cdns->role_override = 1;
379
380 /*
381 * HW state might have changed so driver need to trigger
382 * HW state machine if dr_mode == USB_DR_MODE_OTG.
383 */
384 if (!cdns->role_override && cdns->dr_mode == USB_DR_MODE_OTG) {
385 cdns3_hw_role_switch(cdns);
386 goto pm_put;
387 }
388
389 if (cdns->role == role)
390 goto pm_put;
391
392 if (cdns->dr_mode == USB_DR_MODE_HOST) {
393 switch (role) {
394 case USB_ROLE_NONE:
395 case USB_ROLE_HOST:
396 break;
397 default:
398 ret = -EPERM;
399 goto pm_put;
400 }
401 }
402
403 if (cdns->dr_mode == USB_DR_MODE_PERIPHERAL) {
404 switch (role) {
405 case USB_ROLE_NONE:
406 case USB_ROLE_DEVICE:
407 break;
408 default:
409 ret = -EPERM;
410 goto pm_put;
411 }
412 }
413
414 cdns3_role_stop(cdns);
415 ret = cdns3_role_start(cdns, role);
416 if (ret) {
417 dev_err(cdns->dev, "set role %d has failed\n", role);
418 ret = -EPERM;
419 }
420
421pm_put:
422 pm_runtime_put_sync(cdns->dev);
423 return ret;
424}
425
426static const struct usb_role_switch_desc cdns3_switch_desc = {
427 .set = cdns3_role_set,
428 .get = cdns3_role_get,
429 .allow_userspace_control = true,
430};
431
432/**
433 * cdns3_probe - probe for cdns3 core device
434 * @pdev: Pointer to cdns3 core platform device
435 *
436 * Returns 0 on success otherwise negative errno
437 */
438static int cdns3_probe(struct platform_device *pdev)
439{
440 struct device *dev = &pdev->dev;
441 struct resource *res;
442 struct cdns3 *cdns;
443 void __iomem *regs;
444 int ret;
445
446 ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
447 if (ret) {
448 dev_err(dev, "error setting dma mask: %d\n", ret);
449 return -ENODEV;
450 }
451
452 cdns = devm_kzalloc(dev, sizeof(*cdns), GFP_KERNEL);
453 if (!cdns)
454 return -ENOMEM;
455
456 cdns->dev = dev;
457
458 platform_set_drvdata(pdev, cdns);
459
460 res = platform_get_resource_byname(pdev, IORESOURCE_IRQ, "host");
461 if (!res) {
462 dev_err(dev, "missing host IRQ\n");
463 return -ENODEV;
464 }
465
466 cdns->xhci_res[0] = *res;
467
468 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "xhci");
469 if (!res) {
470 dev_err(dev, "couldn't get xhci resource\n");
471 return -ENXIO;
472 }
473
474 cdns->xhci_res[1] = *res;
475
476 cdns->dev_irq = platform_get_irq_byname(pdev, "peripheral");
477 if (cdns->dev_irq == -EPROBE_DEFER)
478 return cdns->dev_irq;
479
480 if (cdns->dev_irq < 0)
481 dev_err(dev, "couldn't get peripheral irq\n");
482
483 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dev");
484 regs = devm_ioremap_resource(dev, res);
485 if (IS_ERR(regs))
486 return PTR_ERR(regs);
487 cdns->dev_regs = regs;
488
489 cdns->otg_irq = platform_get_irq_byname(pdev, "otg");
490 if (cdns->otg_irq == -EPROBE_DEFER)
491 return cdns->otg_irq;
492
493 if (cdns->otg_irq < 0) {
494 dev_err(dev, "couldn't get otg irq\n");
495 return cdns->otg_irq;
496 }
497
498 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "otg");
499 if (!res) {
500 dev_err(dev, "couldn't get otg resource\n");
501 return -ENXIO;
502 }
503
504 cdns->otg_res = *res;
505
506 mutex_init(&cdns->mutex);
507
508 cdns->usb2_phy = devm_phy_optional_get(dev, "cdns3,usb2-phy");
509 if (IS_ERR(cdns->usb2_phy))
510 return PTR_ERR(cdns->usb2_phy);
511
512 ret = phy_init(cdns->usb2_phy);
513 if (ret)
514 return ret;
515
516 cdns->usb3_phy = devm_phy_optional_get(dev, "cdns3,usb3-phy");
517 if (IS_ERR(cdns->usb3_phy))
518 return PTR_ERR(cdns->usb3_phy);
519
520 ret = phy_init(cdns->usb3_phy);
521 if (ret)
522 goto err1;
523
524 ret = phy_power_on(cdns->usb2_phy);
525 if (ret)
526 goto err2;
527
528 ret = phy_power_on(cdns->usb3_phy);
529 if (ret)
530 goto err3;
531
532 cdns->role_sw = usb_role_switch_register(dev, &cdns3_switch_desc);
533 if (IS_ERR(cdns->role_sw)) {
534 ret = PTR_ERR(cdns->role_sw);
535 dev_warn(dev, "Unable to register Role Switch\n");
536 goto err4;
537 }
538
539 ret = cdns3_drd_init(cdns);
540 if (ret)
541 goto err5;
542
543 ret = cdns3_core_init_role(cdns);
544 if (ret)
545 goto err5;
546
547 device_set_wakeup_capable(dev, true);
548 pm_runtime_set_active(dev);
549 pm_runtime_enable(dev);
550
551 /*
552 * The controller needs less time between bus and controller suspend,
553 * and we also needs a small delay to avoid frequently entering low
554 * power mode.
555 */
556 pm_runtime_set_autosuspend_delay(dev, 20);
557 pm_runtime_mark_last_busy(dev);
558 pm_runtime_use_autosuspend(dev);
559 dev_dbg(dev, "Cadence USB3 core: probe succeed\n");
560
561 return 0;
562err5:
563 cdns3_drd_exit(cdns);
564 usb_role_switch_unregister(cdns->role_sw);
565err4:
566 phy_power_off(cdns->usb3_phy);
567
568err3:
569 phy_power_off(cdns->usb2_phy);
570err2:
571 phy_exit(cdns->usb3_phy);
572err1:
573 phy_exit(cdns->usb2_phy);
574
575 return ret;
576}
577
578/**
579 * cdns3_remove - unbind drd driver and clean up
580 * @pdev: Pointer to Linux platform device
581 *
582 * Returns 0 on success otherwise negative errno
583 */
584static int cdns3_remove(struct platform_device *pdev)
585{
586 struct cdns3 *cdns = platform_get_drvdata(pdev);
587
588 pm_runtime_get_sync(&pdev->dev);
589 pm_runtime_disable(&pdev->dev);
590 pm_runtime_put_noidle(&pdev->dev);
591 cdns3_exit_roles(cdns);
592 usb_role_switch_unregister(cdns->role_sw);
593 phy_power_off(cdns->usb2_phy);
594 phy_power_off(cdns->usb3_phy);
595 phy_exit(cdns->usb2_phy);
596 phy_exit(cdns->usb3_phy);
597 return 0;
598}
599
600#ifdef CONFIG_PM_SLEEP
601
602static int cdns3_suspend(struct device *dev)
603{
604 struct cdns3 *cdns = dev_get_drvdata(dev);
605 unsigned long flags;
606
607 if (cdns->role == USB_ROLE_HOST)
608 return 0;
609
610 if (pm_runtime_status_suspended(dev))
611 pm_runtime_resume(dev);
612
613 if (cdns->roles[cdns->role]->suspend) {
614 spin_lock_irqsave(&cdns->gadget_dev->lock, flags);
615 cdns->roles[cdns->role]->suspend(cdns, false);
616 spin_unlock_irqrestore(&cdns->gadget_dev->lock, flags);
617 }
618
619 return 0;
620}
621
622static int cdns3_resume(struct device *dev)
623{
624 struct cdns3 *cdns = dev_get_drvdata(dev);
625 unsigned long flags;
626
627 if (cdns->role == USB_ROLE_HOST)
628 return 0;
629
630 if (cdns->roles[cdns->role]->resume) {
631 spin_lock_irqsave(&cdns->gadget_dev->lock, flags);
632 cdns->roles[cdns->role]->resume(cdns, false);
633 spin_unlock_irqrestore(&cdns->gadget_dev->lock, flags);
634 }
635
636 pm_runtime_disable(dev);
637 pm_runtime_set_active(dev);
638 pm_runtime_enable(dev);
639
640 return 0;
641}
642#endif
643
644static const struct dev_pm_ops cdns3_pm_ops = {
645 SET_SYSTEM_SLEEP_PM_OPS(cdns3_suspend, cdns3_resume)
646};
647
648#ifdef CONFIG_OF
649static const struct of_device_id of_cdns3_match[] = {
650 { .compatible = "cdns,usb3" },
651 { },
652};
653MODULE_DEVICE_TABLE(of, of_cdns3_match);
654#endif
655
656static struct platform_driver cdns3_driver = {
657 .probe = cdns3_probe,
658 .remove = cdns3_remove,
659 .driver = {
660 .name = "cdns-usb3",
661 .of_match_table = of_match_ptr(of_cdns3_match),
662 .pm = &cdns3_pm_ops,
663 },
664};
665
666module_platform_driver(cdns3_driver);
667
668MODULE_ALIAS("platform:cdns3");
669MODULE_AUTHOR("Pawel Laszczak <pawell@cadence.com>");
670MODULE_LICENSE("GPL v2");
671MODULE_DESCRIPTION("Cadence USB3 DRD Controller Driver");