• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 <common.h>
15 #include <dm.h>
16 #include <dm/device-internal.h>
17 #include <dm/lists.h>
18 #include <linux/kernel.h>
19 #include <linux/io.h>
20 #include <usb.h>
21 #include <usb/xhci.h>
22 
23 #include "core.h"
24 #include "host-export.h"
25 #include "gadget-export.h"
26 #include "drd.h"
27 
28 static int cdns3_idle_init(struct cdns3 *cdns);
29 
30 struct cdns3_host_priv {
31 	struct xhci_ctrl xhci_ctrl;
32 	struct cdns3 cdns;
33 };
34 
35 struct cdns3_gadget_priv {
36 	struct cdns3 cdns;
37 };
38 
39 static inline
cdns3_get_current_role_driver(struct cdns3 * cdns)40 struct cdns3_role_driver *cdns3_get_current_role_driver(struct cdns3 *cdns)
41 {
42 	WARN_ON(!cdns->roles[cdns->role]);
43 	return cdns->roles[cdns->role];
44 }
45 
cdns3_role_start(struct cdns3 * cdns,enum usb_role role)46 static int cdns3_role_start(struct cdns3 *cdns, enum usb_role role)
47 {
48 	int ret;
49 
50 	if (WARN_ON(role > USB_ROLE_DEVICE))
51 		return 0;
52 
53 	mutex_lock(&cdns->mutex);
54 	cdns->role = role;
55 	mutex_unlock(&cdns->mutex);
56 
57 	if (!cdns->roles[role])
58 		return -ENXIO;
59 
60 	if (cdns->roles[role]->state == CDNS3_ROLE_STATE_ACTIVE)
61 		return 0;
62 
63 	mutex_lock(&cdns->mutex);
64 	ret = cdns->roles[role]->start(cdns);
65 	if (!ret)
66 		cdns->roles[role]->state = CDNS3_ROLE_STATE_ACTIVE;
67 	mutex_unlock(&cdns->mutex);
68 
69 	return ret;
70 }
71 
cdns3_role_stop(struct cdns3 * cdns)72 static void cdns3_role_stop(struct cdns3 *cdns)
73 {
74 	enum usb_role role = cdns->role;
75 
76 	if (WARN_ON(role > USB_ROLE_DEVICE))
77 		return;
78 
79 	if (cdns->roles[role]->state == CDNS3_ROLE_STATE_INACTIVE)
80 		return;
81 
82 	mutex_lock(&cdns->mutex);
83 	cdns->roles[role]->stop(cdns);
84 	cdns->roles[role]->state = CDNS3_ROLE_STATE_INACTIVE;
85 	mutex_unlock(&cdns->mutex);
86 }
87 
cdns3_exit_roles(struct cdns3 * cdns)88 static void cdns3_exit_roles(struct cdns3 *cdns)
89 {
90 	cdns3_role_stop(cdns);
91 	cdns3_drd_exit(cdns);
92 }
93 
94 static enum usb_role cdsn3_hw_role_state_machine(struct cdns3 *cdns);
95 
96 /**
97  * cdns3_core_init_role - initialize role of operation
98  * @cdns: Pointer to cdns3 structure
99  *
100  * Returns 0 on success otherwise negative errno
101  */
cdns3_core_init_role(struct cdns3 * cdns)102 static int cdns3_core_init_role(struct cdns3 *cdns)
103 {
104 	struct udevice *dev = cdns->dev;
105 	enum usb_dr_mode best_dr_mode;
106 	enum usb_dr_mode dr_mode;
107 	int ret = 0;
108 
109 	dr_mode = usb_get_dr_mode(dev_of_offset(dev));
110 	cdns->role = USB_ROLE_NONE;
111 
112 	/*
113 	 * If driver can't read mode by means of usb_get_dr_mode function then
114 	 * chooses mode according with Kernel configuration. This setting
115 	 * can be restricted later depending on strap pin configuration.
116 	 */
117 	if (dr_mode == USB_DR_MODE_UNKNOWN) {
118 		if (IS_ENABLED(CONFIG_USB_CDNS3_HOST) &&
119 		    IS_ENABLED(CONFIG_USB_CDNS3_GADGET))
120 			dr_mode = USB_DR_MODE_OTG;
121 		else if (IS_ENABLED(CONFIG_USB_CDNS3_HOST))
122 			dr_mode = USB_DR_MODE_HOST;
123 		else if (IS_ENABLED(CONFIG_USB_CDNS3_GADGET))
124 			dr_mode = USB_DR_MODE_PERIPHERAL;
125 	}
126 
127 	/*
128 	 * At this point cdns->dr_mode contains strap configuration.
129 	 * Driver try update this setting considering kernel configuration
130 	 */
131 	best_dr_mode = cdns->dr_mode;
132 
133 	ret = cdns3_idle_init(cdns);
134 	if (ret)
135 		return ret;
136 
137 	if (dr_mode == USB_DR_MODE_OTG) {
138 		best_dr_mode = cdns->dr_mode;
139 	} else if (cdns->dr_mode == USB_DR_MODE_OTG) {
140 		best_dr_mode = dr_mode;
141 	} else if (cdns->dr_mode != dr_mode) {
142 		dev_err(dev, "Incorrect DRD configuration\n");
143 		return -EINVAL;
144 	}
145 
146 	dr_mode = best_dr_mode;
147 
148 #if defined(CONFIG_SPL_USB_HOST_SUPPORT) || !defined(CONFIG_SPL_BUILD)
149 	if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_HOST) {
150 		ret = cdns3_host_init(cdns);
151 		if (ret) {
152 			dev_err(dev, "Host initialization failed with %d\n",
153 				ret);
154 			goto err;
155 		}
156 	}
157 #endif
158 
159 #if CONFIG_IS_ENABLED(DM_USB_GADGET)
160 	if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_PERIPHERAL) {
161 		ret = cdns3_gadget_init(cdns);
162 		if (ret) {
163 			dev_err(dev, "Device initialization failed with %d\n",
164 				ret);
165 			goto err;
166 		}
167 	}
168 #endif
169 
170 	cdns->dr_mode = dr_mode;
171 
172 	ret = cdns3_drd_update_mode(cdns);
173 	if (ret)
174 		goto err;
175 
176 	if (cdns->dr_mode != USB_DR_MODE_OTG) {
177 		ret = cdns3_hw_role_switch(cdns);
178 		if (ret)
179 			goto err;
180 	}
181 
182 	return ret;
183 err:
184 	cdns3_exit_roles(cdns);
185 	return ret;
186 }
187 
188 /**
189  * cdsn3_hw_role_state_machine - role switch state machine based on hw events
190  * @cdns: Pointer to controller structure.
191  *
192  * Returns next role to be entered based on hw events.
193  */
cdsn3_hw_role_state_machine(struct cdns3 * cdns)194 static enum usb_role cdsn3_hw_role_state_machine(struct cdns3 *cdns)
195 {
196 	enum usb_role role;
197 	int id, vbus;
198 
199 	if (cdns->dr_mode != USB_DR_MODE_OTG)
200 		goto not_otg;
201 
202 	id = cdns3_get_id(cdns);
203 	vbus = cdns3_get_vbus(cdns);
204 
205 	/*
206 	 * Role change state machine
207 	 * Inputs: ID, VBUS
208 	 * Previous state: cdns->role
209 	 * Next state: role
210 	 */
211 	role = cdns->role;
212 
213 	switch (role) {
214 	case USB_ROLE_NONE:
215 		/*
216 		 * Driver treats USB_ROLE_NONE synonymous to IDLE state from
217 		 * controller specification.
218 		 */
219 		if (!id)
220 			role = USB_ROLE_HOST;
221 		else if (vbus)
222 			role = USB_ROLE_DEVICE;
223 		break;
224 	case USB_ROLE_HOST: /* from HOST, we can only change to NONE */
225 		if (id)
226 			role = USB_ROLE_NONE;
227 		break;
228 	case USB_ROLE_DEVICE: /* from GADGET, we can only change to NONE*/
229 		if (!vbus)
230 			role = USB_ROLE_NONE;
231 		break;
232 	}
233 
234 	dev_dbg(cdns->dev, "role %d -> %d\n", cdns->role, role);
235 
236 	return role;
237 
238 not_otg:
239 	if (cdns3_is_host(cdns))
240 		role = USB_ROLE_HOST;
241 	if (cdns3_is_device(cdns))
242 		role = USB_ROLE_DEVICE;
243 
244 	return role;
245 }
246 
cdns3_idle_role_start(struct cdns3 * cdns)247 static int cdns3_idle_role_start(struct cdns3 *cdns)
248 {
249 	return 0;
250 }
251 
cdns3_idle_role_stop(struct cdns3 * cdns)252 static void cdns3_idle_role_stop(struct cdns3 *cdns)
253 {
254 	/* Program Lane swap and bring PHY out of RESET */
255 	generic_phy_reset(&cdns->usb3_phy);
256 }
257 
cdns3_idle_init(struct cdns3 * cdns)258 static int cdns3_idle_init(struct cdns3 *cdns)
259 {
260 	struct cdns3_role_driver *rdrv;
261 
262 	rdrv = devm_kzalloc(cdns->dev, sizeof(*rdrv), GFP_KERNEL);
263 	if (!rdrv)
264 		return -ENOMEM;
265 
266 	rdrv->start = cdns3_idle_role_start;
267 	rdrv->stop = cdns3_idle_role_stop;
268 	rdrv->state = CDNS3_ROLE_STATE_INACTIVE;
269 	rdrv->suspend = NULL;
270 	rdrv->resume = NULL;
271 	rdrv->name = "idle";
272 
273 	cdns->roles[USB_ROLE_NONE] = rdrv;
274 
275 	return 0;
276 }
277 
278 /**
279  * cdns3_hw_role_switch - switch roles based on HW state
280  * @cdns3: controller
281  */
cdns3_hw_role_switch(struct cdns3 * cdns)282 int cdns3_hw_role_switch(struct cdns3 *cdns)
283 {
284 	enum usb_role real_role, current_role;
285 	int ret = 0;
286 
287 	/* Do nothing if role based on syfs. */
288 	if (cdns->role_override)
289 		return 0;
290 
291 	current_role = cdns->role;
292 	real_role = cdsn3_hw_role_state_machine(cdns);
293 
294 	/* Do nothing if nothing changed */
295 	if (current_role == real_role)
296 		goto exit;
297 
298 	cdns3_role_stop(cdns);
299 
300 	dev_dbg(cdns->dev, "Switching role %d -> %d", current_role, real_role);
301 
302 	ret = cdns3_role_start(cdns, real_role);
303 	if (ret) {
304 		/* Back to current role */
305 		dev_err(cdns->dev, "set %d has failed, back to %d\n",
306 			real_role, current_role);
307 		ret = cdns3_role_start(cdns, current_role);
308 		if (ret)
309 			dev_err(cdns->dev, "back to %d failed too\n",
310 				current_role);
311 	}
312 exit:
313 	return ret;
314 }
315 
cdns3_probe(struct cdns3 * cdns)316 static int cdns3_probe(struct cdns3 *cdns)
317 {
318 	struct udevice *dev = cdns->dev;
319 	int ret;
320 
321 	cdns->xhci_regs = dev_remap_addr_name(dev, "xhci");
322 	if (!cdns->xhci_regs)
323 		return -EINVAL;
324 
325 	cdns->dev_regs = dev_remap_addr_name(dev, "dev");
326 	if (!cdns->dev_regs)
327 		return -EINVAL;
328 
329 	mutex_init(&cdns->mutex);
330 
331 	ret = generic_phy_get_by_name(dev, "cdns3,usb2-phy", &cdns->usb2_phy);
332 	if (ret)
333 		dev_warn(dev, "Unable to get USB2 phy (ret %d)\n", ret);
334 
335 	ret = generic_phy_init(&cdns->usb2_phy);
336 	if (ret)
337 		return ret;
338 
339 	ret = generic_phy_get_by_name(dev, "cdns3,usb3-phy", &cdns->usb3_phy);
340 	if (ret)
341 		dev_warn(dev, "Unable to get USB3 phy (ret %d)\n", ret);
342 
343 	ret = generic_phy_init(&cdns->usb3_phy);
344 	if (ret)
345 		return ret;
346 
347 	ret = generic_phy_power_on(&cdns->usb2_phy);
348 	if (ret)
349 		return ret;
350 
351 	ret = generic_phy_power_on(&cdns->usb3_phy);
352 	if (ret)
353 		return ret;
354 
355 	ret = cdns3_drd_init(cdns);
356 	if (ret)
357 		return ret;
358 
359 	ret = cdns3_core_init_role(cdns);
360 	if (ret)
361 		return ret;
362 
363 	dev_dbg(dev, "Cadence USB3 core: probe succeed\n");
364 
365 	return 0;
366 }
367 
cdns3_remove(struct cdns3 * cdns)368 static int cdns3_remove(struct cdns3 *cdns)
369 {
370 	cdns3_exit_roles(cdns);
371 	generic_phy_power_off(&cdns->usb2_phy);
372 	generic_phy_power_off(&cdns->usb3_phy);
373 	generic_phy_exit(&cdns->usb2_phy);
374 	generic_phy_exit(&cdns->usb3_phy);
375 	return 0;
376 }
377 
378 static const struct udevice_id cdns3_ids[] = {
379 	{ .compatible = "cdns,usb3" },
380 	{ },
381 };
382 
cdns3_bind(struct udevice * parent)383 int cdns3_bind(struct udevice *parent)
384 {
385 	int from = dev_of_offset(parent);
386 	const void *fdt = gd->fdt_blob;
387 	enum usb_dr_mode dr_mode;
388 	struct udevice *dev;
389 	const char *driver;
390 	const char *name;
391 	int node;
392 	int ret;
393 
394 	node = fdt_node_offset_by_compatible(fdt, from, "cdns,usb3");
395 	if (node < 0) {
396 		ret = -ENODEV;
397 		goto fail;
398 	}
399 
400 	name = fdt_get_name(fdt, node, NULL);
401 	dr_mode = usb_get_dr_mode(node);
402 
403 	switch (dr_mode) {
404 #if defined(CONFIG_SPL_USB_HOST_SUPPORT) || \
405 	(!defined(CONFIG_SPL_BUILD) && defined(CONFIG_USB_HOST))
406 	case USB_DR_MODE_HOST:
407 		debug("%s: dr_mode: HOST\n", __func__);
408 		driver = "cdns-usb3-host";
409 		break;
410 #endif
411 #if CONFIG_IS_ENABLED(DM_USB_GADGET)
412 	case USB_DR_MODE_PERIPHERAL:
413 		debug("%s: dr_mode: PERIPHERAL\n", __func__);
414 		driver = "cdns-usb3-peripheral";
415 		break;
416 #endif
417 	default:
418 		printf("%s: unsupported dr_mode\n", __func__);
419 		ret = -ENODEV;
420 		goto fail;
421 	};
422 
423 	ret = device_bind_driver_to_node(parent, driver, name,
424 					 offset_to_ofnode(node), &dev);
425 	if (ret) {
426 		printf("%s: not able to bind usb device mode\n",
427 		       __func__);
428 		goto fail;
429 	}
430 
431 	return 0;
432 
433 fail:
434 	/* do not return an error: failing to bind would hang the board */
435 	return 0;
436 }
437 
438 #if CONFIG_IS_ENABLED(DM_USB_GADGET)
cdns3_gadget_probe(struct udevice * dev)439 static int cdns3_gadget_probe(struct udevice *dev)
440 {
441 	struct cdns3_gadget_priv *priv = dev_get_priv(dev);
442 	struct cdns3 *cdns = &priv->cdns;
443 
444 	cdns->dev = dev;
445 
446 	return cdns3_probe(cdns);
447 }
448 
cdns3_gadget_remove(struct udevice * dev)449 static int cdns3_gadget_remove(struct udevice *dev)
450 {
451 	struct cdns3_gadget_priv *priv = dev_get_priv(dev);
452 	struct cdns3 *cdns = &priv->cdns;
453 
454 	return cdns3_remove(cdns);
455 }
456 
457 U_BOOT_DRIVER(cdns_usb3_peripheral) = {
458 	.name	= "cdns-usb3-peripheral",
459 	.id	= UCLASS_USB_GADGET_GENERIC,
460 	.of_match = cdns3_ids,
461 	.probe = cdns3_gadget_probe,
462 	.remove = cdns3_gadget_remove,
463 	.priv_auto_alloc_size = sizeof(struct cdns3_gadget_priv),
464 	.flags = DM_FLAG_ALLOC_PRIV_DMA,
465 };
466 #endif
467 
468 #if defined(CONFIG_SPL_USB_HOST_SUPPORT) || \
469 	(!defined(CONFIG_SPL_BUILD) && defined(CONFIG_USB_HOST))
cdns3_host_probe(struct udevice * dev)470 static int cdns3_host_probe(struct udevice *dev)
471 {
472 	struct cdns3_host_priv *priv = dev_get_priv(dev);
473 	struct cdns3 *cdns = &priv->cdns;
474 
475 	cdns->dev = dev;
476 
477 	return cdns3_probe(cdns);
478 }
479 
cdns3_host_remove(struct udevice * dev)480 static int cdns3_host_remove(struct udevice *dev)
481 {
482 	struct cdns3_host_priv *priv = dev_get_priv(dev);
483 	struct cdns3 *cdns = &priv->cdns;
484 
485 	return cdns3_remove(cdns);
486 }
487 
488 U_BOOT_DRIVER(cdns_usb3_host) = {
489 	.name	= "cdns-usb3-host",
490 	.id	= UCLASS_USB,
491 	.of_match = cdns3_ids,
492 	.probe = cdns3_host_probe,
493 	.remove = cdns3_host_remove,
494 	.priv_auto_alloc_size = sizeof(struct cdns3_host_priv),
495 	.ops = &xhci_usb_ops,
496 	.flags = DM_FLAG_ALLOC_PRIV_DMA,
497 };
498 #endif
499