1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * aspeed-vhub -- Driver for Aspeed SoC "vHub" USB gadget
4  *
5  * dev.c - Individual device/gadget management (ie, a port = a gadget)
6  *
7  * Copyright 2017 IBM Corporation
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  */
14 
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/platform_device.h>
18 #include <linux/delay.h>
19 #include <linux/ioport.h>
20 #include <linux/slab.h>
21 #include <linux/errno.h>
22 #include <linux/list.h>
23 #include <linux/interrupt.h>
24 #include <linux/proc_fs.h>
25 #include <linux/prefetch.h>
26 #include <linux/clk.h>
27 #include <linux/usb/gadget.h>
28 #include <linux/of.h>
29 #include <linux/of_gpio.h>
30 #include <linux/regmap.h>
31 #include <linux/dma-mapping.h>
32 #include <linux/usb.h>
33 #include <linux/usb/hcd.h>
34 
35 #include "vhub.h"
36 
37 void ast_vhub_dev_irq(struct ast_vhub_dev *d)
38 {
39 	u32 istat = readl(d->regs + AST_VHUB_DEV_ISR);
40 
41 	writel(istat, d->regs + AST_VHUB_DEV_ISR);
42 
43 	if (istat & VHUV_DEV_IRQ_EP0_IN_ACK_STALL)
44 		ast_vhub_ep0_handle_ack(&d->ep0, true);
45 	if (istat & VHUV_DEV_IRQ_EP0_OUT_ACK_STALL)
46 		ast_vhub_ep0_handle_ack(&d->ep0, false);
47 	if (istat & VHUV_DEV_IRQ_EP0_SETUP)
48 		ast_vhub_ep0_handle_setup(&d->ep0);
49 }
50 
51 static void ast_vhub_dev_enable(struct ast_vhub_dev *d)
52 {
53 	u32 reg, hmsk, i;
54 
55 	if (d->enabled)
56 		return;
57 
58 	/* Cleanup EP0 state */
59 	ast_vhub_reset_ep0(d);
60 
61 	/* Enable device and its EP0 interrupts */
62 	reg = VHUB_DEV_EN_ENABLE_PORT |
63 		VHUB_DEV_EN_EP0_IN_ACK_IRQEN |
64 		VHUB_DEV_EN_EP0_OUT_ACK_IRQEN |
65 		VHUB_DEV_EN_EP0_SETUP_IRQEN;
66 	if (d->gadget.speed == USB_SPEED_HIGH)
67 		reg |= VHUB_DEV_EN_SPEED_SEL_HIGH;
68 	writel(reg, d->regs + AST_VHUB_DEV_EN_CTRL);
69 
70 	/* Enable device interrupt in the hub as well */
71 	hmsk = VHUB_IRQ_DEVICE1 << d->index;
72 	reg = readl(d->vhub->regs + AST_VHUB_IER);
73 	reg |= hmsk;
74 	writel(reg, d->vhub->regs + AST_VHUB_IER);
75 
76 	/* Set EP0 DMA buffer address */
77 	writel(d->ep0.buf_dma, d->regs + AST_VHUB_DEV_EP0_DATA);
78 
79 	/* Clear stall on all EPs */
80 	for (i = 0; i < AST_VHUB_NUM_GEN_EPs; i++) {
81 		struct ast_vhub_ep *ep = d->epns[i];
82 
83 		if (ep && (ep->epn.stalled || ep->epn.wedged)) {
84 			ep->epn.stalled = false;
85 			ep->epn.wedged = false;
86 			ast_vhub_update_epn_stall(ep);
87 		}
88 	}
89 
90 	/* Additional cleanups */
91 	d->wakeup_en = false;
92 	d->enabled = true;
93 }
94 
95 static void ast_vhub_dev_disable(struct ast_vhub_dev *d)
96 {
97 	u32 reg, hmsk;
98 
99 	if (!d->enabled)
100 		return;
101 
102 	/* Disable device interrupt in the hub */
103 	hmsk = VHUB_IRQ_DEVICE1 << d->index;
104 	reg = readl(d->vhub->regs + AST_VHUB_IER);
105 	reg &= ~hmsk;
106 	writel(reg, d->vhub->regs + AST_VHUB_IER);
107 
108 	/* Then disable device */
109 	writel(0, d->regs + AST_VHUB_DEV_EN_CTRL);
110 	d->gadget.speed = USB_SPEED_UNKNOWN;
111 	d->enabled = false;
112 }
113 
114 static int ast_vhub_dev_feature(struct ast_vhub_dev *d,
115 				u16 wIndex, u16 wValue,
116 				bool is_set)
117 {
118 	DDBG(d, "%s_FEATURE(dev val=%02x)\n",
119 	     is_set ? "SET" : "CLEAR", wValue);
120 
121 	if (wValue != USB_DEVICE_REMOTE_WAKEUP)
122 		return std_req_driver;
123 
124 	d->wakeup_en = is_set;
125 
126 	return std_req_complete;
127 }
128 
129 static int ast_vhub_ep_feature(struct ast_vhub_dev *d,
130 			       u16 wIndex, u16 wValue, bool is_set)
131 {
132 	struct ast_vhub_ep *ep;
133 	int ep_num;
134 
135 	ep_num = wIndex & USB_ENDPOINT_NUMBER_MASK;
136 	DDBG(d, "%s_FEATURE(ep%d val=%02x)\n",
137 	     is_set ? "SET" : "CLEAR", ep_num, wValue);
138 	if (ep_num == 0)
139 		return std_req_complete;
140 	if (ep_num >= AST_VHUB_NUM_GEN_EPs || !d->epns[ep_num - 1])
141 		return std_req_stall;
142 	if (wValue != USB_ENDPOINT_HALT)
143 		return std_req_driver;
144 
145 	ep = d->epns[ep_num - 1];
146 	if (WARN_ON(!ep))
147 		return std_req_stall;
148 
149 	if (!ep->epn.enabled || !ep->ep.desc || ep->epn.is_iso ||
150 	    ep->epn.is_in != !!(wIndex & USB_DIR_IN))
151 		return std_req_stall;
152 
153 	DDBG(d, "%s stall on EP %d\n",
154 	     is_set ? "setting" : "clearing", ep_num);
155 	ep->epn.stalled = is_set;
156 	ast_vhub_update_epn_stall(ep);
157 
158 	return std_req_complete;
159 }
160 
161 static int ast_vhub_dev_status(struct ast_vhub_dev *d,
162 			       u16 wIndex, u16 wValue)
163 {
164 	u8 st0;
165 
166 	DDBG(d, "GET_STATUS(dev)\n");
167 
168 	st0 = d->gadget.is_selfpowered << USB_DEVICE_SELF_POWERED;
169 	if (d->wakeup_en)
170 		st0 |= 1 << USB_DEVICE_REMOTE_WAKEUP;
171 
172 	return ast_vhub_simple_reply(&d->ep0, st0, 0);
173 }
174 
175 static int ast_vhub_ep_status(struct ast_vhub_dev *d,
176 			      u16 wIndex, u16 wValue)
177 {
178 	int ep_num = wIndex & USB_ENDPOINT_NUMBER_MASK;
179 	struct ast_vhub_ep *ep;
180 	u8 st0 = 0;
181 
182 	DDBG(d, "GET_STATUS(ep%d)\n", ep_num);
183 
184 	if (ep_num >= AST_VHUB_NUM_GEN_EPs)
185 		return std_req_stall;
186 	if (ep_num != 0) {
187 		ep = d->epns[ep_num - 1];
188 		if (!ep)
189 			return std_req_stall;
190 		if (!ep->epn.enabled || !ep->ep.desc || ep->epn.is_iso ||
191 		    ep->epn.is_in != !!(wIndex & USB_DIR_IN))
192 			return std_req_stall;
193 		if (ep->epn.stalled)
194 			st0 |= 1 << USB_ENDPOINT_HALT;
195 	}
196 
197 	return ast_vhub_simple_reply(&d->ep0, st0, 0);
198 }
199 
200 static void ast_vhub_dev_set_address(struct ast_vhub_dev *d, u8 addr)
201 {
202 	u32 reg;
203 
204 	DDBG(d, "SET_ADDRESS: Got address %x\n", addr);
205 
206 	reg = readl(d->regs + AST_VHUB_DEV_EN_CTRL);
207 	reg &= ~VHUB_DEV_EN_ADDR_MASK;
208 	reg |= VHUB_DEV_EN_SET_ADDR(addr);
209 	writel(reg, d->regs + AST_VHUB_DEV_EN_CTRL);
210 }
211 
212 int ast_vhub_std_dev_request(struct ast_vhub_ep *ep,
213 			     struct usb_ctrlrequest *crq)
214 {
215 	struct ast_vhub_dev *d = ep->dev;
216 	u16 wValue, wIndex;
217 
218 	/* No driver, we shouldn't be enabled ... */
219 	if (!d->driver || !d->enabled) {
220 		EPDBG(ep,
221 		      "Device is wrong state driver=%p enabled=%d\n",
222 		      d->driver, d->enabled);
223 		return std_req_stall;
224 	}
225 
226 	/*
227 	 * Note: we used to reject/stall requests while suspended,
228 	 * we don't do that anymore as we seem to have cases of
229 	 * mass storage getting very upset.
230 	 */
231 
232 	/* First packet, grab speed */
233 	if (d->gadget.speed == USB_SPEED_UNKNOWN) {
234 		d->gadget.speed = ep->vhub->speed;
235 		if (d->gadget.speed > d->driver->max_speed)
236 			d->gadget.speed = d->driver->max_speed;
237 		DDBG(d, "fist packet, captured speed %d\n",
238 		     d->gadget.speed);
239 	}
240 
241 	wValue = le16_to_cpu(crq->wValue);
242 	wIndex = le16_to_cpu(crq->wIndex);
243 
244 	switch ((crq->bRequestType << 8) | crq->bRequest) {
245 		/* SET_ADDRESS */
246 	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
247 		ast_vhub_dev_set_address(d, wValue);
248 		return std_req_complete;
249 
250 		/* GET_STATUS */
251 	case DeviceRequest | USB_REQ_GET_STATUS:
252 		return ast_vhub_dev_status(d, wIndex, wValue);
253 	case InterfaceRequest | USB_REQ_GET_STATUS:
254 		return ast_vhub_simple_reply(ep, 0, 0);
255 	case EndpointRequest | USB_REQ_GET_STATUS:
256 		return ast_vhub_ep_status(d, wIndex, wValue);
257 
258 		/* SET/CLEAR_FEATURE */
259 	case DeviceOutRequest | USB_REQ_SET_FEATURE:
260 		return ast_vhub_dev_feature(d, wIndex, wValue, true);
261 	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
262 		return ast_vhub_dev_feature(d, wIndex, wValue, false);
263 	case EndpointOutRequest | USB_REQ_SET_FEATURE:
264 		return ast_vhub_ep_feature(d, wIndex, wValue, true);
265 	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
266 		return ast_vhub_ep_feature(d, wIndex, wValue, false);
267 	}
268 	return std_req_driver;
269 }
270 
271 static int ast_vhub_udc_wakeup(struct usb_gadget* gadget)
272 {
273 	struct ast_vhub_dev *d = to_ast_dev(gadget);
274 	unsigned long flags;
275 	int rc = -EINVAL;
276 
277 	spin_lock_irqsave(&d->vhub->lock, flags);
278 	if (!d->wakeup_en)
279 		goto err;
280 
281 	DDBG(d, "Device initiated wakeup\n");
282 
283 	/* Wakeup the host */
284 	ast_vhub_hub_wake_all(d->vhub);
285 	rc = 0;
286  err:
287 	spin_unlock_irqrestore(&d->vhub->lock, flags);
288 	return rc;
289 }
290 
291 static int ast_vhub_udc_get_frame(struct usb_gadget* gadget)
292 {
293 	struct ast_vhub_dev *d = to_ast_dev(gadget);
294 
295 	return (readl(d->vhub->regs + AST_VHUB_USBSTS) >> 16) & 0x7ff;
296 }
297 
298 static void ast_vhub_dev_nuke(struct ast_vhub_dev *d)
299 {
300 	unsigned int i;
301 
302 	for (i = 0; i < AST_VHUB_NUM_GEN_EPs; i++) {
303 		if (!d->epns[i])
304 			continue;
305 		ast_vhub_nuke(d->epns[i], -ESHUTDOWN);
306 	}
307 }
308 
309 static int ast_vhub_udc_pullup(struct usb_gadget* gadget, int on)
310 {
311 	struct ast_vhub_dev *d = to_ast_dev(gadget);
312 	unsigned long flags;
313 
314 	spin_lock_irqsave(&d->vhub->lock, flags);
315 
316 	DDBG(d, "pullup(%d)\n", on);
317 
318 	/* Mark disconnected in the hub */
319 	ast_vhub_device_connect(d->vhub, d->index, on);
320 
321 	/*
322 	 * If enabled, nuke all requests if any (there shouldn't be)
323 	 * and disable the port. This will clear the address too.
324 	 */
325 	if (d->enabled) {
326 		ast_vhub_dev_nuke(d);
327 		ast_vhub_dev_disable(d);
328 	}
329 
330 	spin_unlock_irqrestore(&d->vhub->lock, flags);
331 
332 	return 0;
333 }
334 
335 static int ast_vhub_udc_start(struct usb_gadget *gadget,
336 			      struct usb_gadget_driver *driver)
337 {
338 	struct ast_vhub_dev *d = to_ast_dev(gadget);
339 	unsigned long flags;
340 
341 	spin_lock_irqsave(&d->vhub->lock, flags);
342 
343 	DDBG(d, "start\n");
344 
345 	/* We don't do much more until the hub enables us */
346 	d->driver = driver;
347 	d->gadget.is_selfpowered = 1;
348 
349 	spin_unlock_irqrestore(&d->vhub->lock, flags);
350 
351 	return 0;
352 }
353 
354 static struct usb_ep *ast_vhub_udc_match_ep(struct usb_gadget *gadget,
355 					    struct usb_endpoint_descriptor *desc,
356 					    struct usb_ss_ep_comp_descriptor *ss)
357 {
358 	struct ast_vhub_dev *d = to_ast_dev(gadget);
359 	struct ast_vhub_ep *ep;
360 	struct usb_ep *u_ep;
361 	unsigned int max, addr, i;
362 
363 	DDBG(d, "Match EP type %d\n", usb_endpoint_type(desc));
364 
365 	/*
366 	 * First we need to look for an existing unclaimed EP as another
367 	 * configuration may have already associated a bunch of EPs with
368 	 * this gadget. This duplicates the code in usb_ep_autoconfig_ss()
369 	 * unfortunately.
370 	 */
371 	list_for_each_entry(u_ep, &gadget->ep_list, ep_list) {
372 		if (usb_gadget_ep_match_desc(gadget, u_ep, desc, ss)) {
373 			DDBG(d, " -> using existing EP%d\n",
374 			     to_ast_ep(u_ep)->d_idx);
375 			return u_ep;
376 		}
377 	}
378 
379 	/*
380 	 * We didn't find one, we need to grab one from the pool.
381 	 *
382 	 * First let's do some sanity checking
383 	 */
384 	switch(usb_endpoint_type(desc)) {
385 	case USB_ENDPOINT_XFER_CONTROL:
386 		/* Only EP0 can be a control endpoint */
387 		return NULL;
388 	case USB_ENDPOINT_XFER_ISOC:
389 		/* ISO:	 limit 1023 bytes full speed, 1024 high/super speed */
390 		if (gadget_is_dualspeed(gadget))
391 			max = 1024;
392 		else
393 			max = 1023;
394 		break;
395 	case USB_ENDPOINT_XFER_BULK:
396 		if (gadget_is_dualspeed(gadget))
397 			max = 512;
398 		else
399 			max = 64;
400 		break;
401 	case USB_ENDPOINT_XFER_INT:
402 		if (gadget_is_dualspeed(gadget))
403 			max = 1024;
404 		else
405 			max = 64;
406 		break;
407 	}
408 	if (usb_endpoint_maxp(desc) > max)
409 		return NULL;
410 
411 	/*
412 	 * Find a free EP address for that device. We can't
413 	 * let the generic code assign these as it would
414 	 * create overlapping numbers for IN and OUT which
415 	 * we don't support, so also create a suitable name
416 	 * that will allow the generic code to use our
417 	 * assigned address.
418 	 */
419 	for (i = 0; i < AST_VHUB_NUM_GEN_EPs; i++)
420 		if (d->epns[i] == NULL)
421 			break;
422 	if (i >= AST_VHUB_NUM_GEN_EPs)
423 		return NULL;
424 	addr = i + 1;
425 
426 	/*
427 	 * Now grab an EP from the shared pool and associate
428 	 * it with our device
429 	 */
430 	ep = ast_vhub_alloc_epn(d, addr);
431 	if (!ep)
432 		return NULL;
433 	DDBG(d, "Allocated epn#%d for port EP%d\n",
434 	     ep->epn.g_idx, addr);
435 
436 	return &ep->ep;
437 }
438 
439 static int ast_vhub_udc_stop(struct usb_gadget *gadget)
440 {
441 	struct ast_vhub_dev *d = to_ast_dev(gadget);
442 	unsigned long flags;
443 
444 	spin_lock_irqsave(&d->vhub->lock, flags);
445 
446 	DDBG(d, "stop\n");
447 
448 	d->driver = NULL;
449 	d->gadget.speed = USB_SPEED_UNKNOWN;
450 
451 	ast_vhub_dev_nuke(d);
452 
453 	if (d->enabled)
454 		ast_vhub_dev_disable(d);
455 
456 	spin_unlock_irqrestore(&d->vhub->lock, flags);
457 
458 	return 0;
459 }
460 
461 static const struct usb_gadget_ops ast_vhub_udc_ops = {
462 	.get_frame	= ast_vhub_udc_get_frame,
463 	.wakeup		= ast_vhub_udc_wakeup,
464 	.pullup		= ast_vhub_udc_pullup,
465 	.udc_start	= ast_vhub_udc_start,
466 	.udc_stop	= ast_vhub_udc_stop,
467 	.match_ep	= ast_vhub_udc_match_ep,
468 };
469 
470 void ast_vhub_dev_suspend(struct ast_vhub_dev *d)
471 {
472 	if (d->driver && d->driver->suspend) {
473 		spin_unlock(&d->vhub->lock);
474 		d->driver->suspend(&d->gadget);
475 		spin_lock(&d->vhub->lock);
476 	}
477 }
478 
479 void ast_vhub_dev_resume(struct ast_vhub_dev *d)
480 {
481 	if (d->driver && d->driver->resume) {
482 		spin_unlock(&d->vhub->lock);
483 		d->driver->resume(&d->gadget);
484 		spin_lock(&d->vhub->lock);
485 	}
486 }
487 
488 void ast_vhub_dev_reset(struct ast_vhub_dev *d)
489 {
490 	/* No driver, just disable the device and return */
491 	if (!d->driver) {
492 		ast_vhub_dev_disable(d);
493 		return;
494 	}
495 
496 	/* If the port isn't enabled, just enable it */
497 	if (!d->enabled) {
498 		DDBG(d, "Reset of disabled device, enabling...\n");
499 		ast_vhub_dev_enable(d);
500 	} else {
501 		DDBG(d, "Reset of enabled device, resetting...\n");
502 		spin_unlock(&d->vhub->lock);
503 		usb_gadget_udc_reset(&d->gadget, d->driver);
504 		spin_lock(&d->vhub->lock);
505 
506 		/*
507 		 * Disable and maybe re-enable HW, this will clear the address
508 		 * and speed setting.
509 		 */
510 		ast_vhub_dev_disable(d);
511 		ast_vhub_dev_enable(d);
512 	}
513 }
514 
515 void ast_vhub_del_dev(struct ast_vhub_dev *d)
516 {
517 	unsigned long flags;
518 
519 	spin_lock_irqsave(&d->vhub->lock, flags);
520 	if (!d->registered) {
521 		spin_unlock_irqrestore(&d->vhub->lock, flags);
522 		return;
523 	}
524 	d->registered = false;
525 	spin_unlock_irqrestore(&d->vhub->lock, flags);
526 
527 	usb_del_gadget_udc(&d->gadget);
528 	device_unregister(d->port_dev);
529 }
530 
531 static void ast_vhub_dev_release(struct device *dev)
532 {
533 	kfree(dev);
534 }
535 
536 int ast_vhub_init_dev(struct ast_vhub *vhub, unsigned int idx)
537 {
538 	struct ast_vhub_dev *d = &vhub->ports[idx].dev;
539 	struct device *parent = &vhub->pdev->dev;
540 	int rc;
541 
542 	d->vhub = vhub;
543 	d->index = idx;
544 	d->name = devm_kasprintf(parent, GFP_KERNEL, "port%d", idx+1);
545 	d->regs = vhub->regs + 0x100 + 0x10 * idx;
546 
547 	ast_vhub_init_ep0(vhub, &d->ep0, d);
548 
549 	/*
550 	 * The UDC core really needs us to have separate and uniquely
551 	 * named "parent" devices for each port so we create a sub device
552 	 * here for that purpose
553 	 */
554 	d->port_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
555 	if (!d->port_dev)
556 		return -ENOMEM;
557 	device_initialize(d->port_dev);
558 	d->port_dev->release = ast_vhub_dev_release;
559 	d->port_dev->parent = parent;
560 	dev_set_name(d->port_dev, "%s:p%d", dev_name(parent), idx + 1);
561 	rc = device_add(d->port_dev);
562 	if (rc)
563 		goto fail_add;
564 
565 	/* Populate gadget */
566 	INIT_LIST_HEAD(&d->gadget.ep_list);
567 	d->gadget.ops = &ast_vhub_udc_ops;
568 	d->gadget.ep0 = &d->ep0.ep;
569 	d->gadget.name = KBUILD_MODNAME;
570 	if (vhub->force_usb1)
571 		d->gadget.max_speed = USB_SPEED_FULL;
572 	else
573 		d->gadget.max_speed = USB_SPEED_HIGH;
574 	d->gadget.speed = USB_SPEED_UNKNOWN;
575 	d->gadget.dev.of_node = vhub->pdev->dev.of_node;
576 
577 	rc = usb_add_gadget_udc(d->port_dev, &d->gadget);
578 	if (rc != 0)
579 		goto fail_udc;
580 	d->registered = true;
581 
582 	return 0;
583  fail_udc:
584 	device_del(d->port_dev);
585  fail_add:
586 	put_device(d->port_dev);
587 
588 	return rc;
589 }
590