1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Handles the Intel 27x USB Device Controller (UDC)
4  *
5  * Inspired by original driver by Frank Becker, David Brownell, and others.
6  * Copyright (C) 2008 Robert Jarzmik
7  */
8 #include <linux/module.h>
9 #include <linux/kernel.h>
10 #include <linux/types.h>
11 #include <linux/errno.h>
12 #include <linux/err.h>
13 #include <linux/platform_device.h>
14 #include <linux/delay.h>
15 #include <linux/list.h>
16 #include <linux/interrupt.h>
17 #include <linux/proc_fs.h>
18 #include <linux/clk.h>
19 #include <linux/irq.h>
20 #include <linux/gpio.h>
21 #include <linux/gpio/consumer.h>
22 #include <linux/slab.h>
23 #include <linux/prefetch.h>
24 #include <linux/byteorder/generic.h>
25 #include <linux/platform_data/pxa2xx_udc.h>
26 #include <linux/of.h>
27 #include <linux/of_gpio.h>
28 
29 #include <linux/usb.h>
30 #include <linux/usb/ch9.h>
31 #include <linux/usb/gadget.h>
32 #include <linux/usb/phy.h>
33 
34 #include "pxa27x_udc.h"
35 
36 /*
37  * This driver handles the USB Device Controller (UDC) in Intel's PXA 27x
38  * series processors.
39  *
40  * Such controller drivers work with a gadget driver.  The gadget driver
41  * returns descriptors, implements configuration and data protocols used
42  * by the host to interact with this device, and allocates endpoints to
43  * the different protocol interfaces.  The controller driver virtualizes
44  * usb hardware so that the gadget drivers will be more portable.
45  *
46  * This UDC hardware wants to implement a bit too much USB protocol. The
47  * biggest issues are:  that the endpoints have to be set up before the
48  * controller can be enabled (minor, and not uncommon); and each endpoint
49  * can only have one configuration, interface and alternative interface
50  * number (major, and very unusual). Once set up, these cannot be changed
51  * without a controller reset.
52  *
53  * The workaround is to setup all combinations necessary for the gadgets which
54  * will work with this driver. This is done in pxa_udc structure, statically.
55  * See pxa_udc, udc_usb_ep versus pxa_ep, and matching function find_pxa_ep.
56  * (You could modify this if needed.  Some drivers have a "fifo_mode" module
57  * parameter to facilitate such changes.)
58  *
59  * The combinations have been tested with these gadgets :
60  *  - zero gadget
61  *  - file storage gadget
62  *  - ether gadget
63  *
64  * The driver doesn't use DMA, only IO access and IRQ callbacks. No use is
65  * made of UDC's double buffering either. USB "On-The-Go" is not implemented.
66  *
67  * All the requests are handled the same way :
68  *  - the drivers tries to handle the request directly to the IO
69  *  - if the IO fifo is not big enough, the remaining is send/received in
70  *    interrupt handling.
71  */
72 
73 #define	DRIVER_VERSION	"2008-04-18"
74 #define	DRIVER_DESC	"PXA 27x USB Device Controller driver"
75 
76 static const char driver_name[] = "pxa27x_udc";
77 static struct pxa_udc *the_controller;
78 
79 static void handle_ep(struct pxa_ep *ep);
80 
81 /*
82  * Debug filesystem
83  */
84 #ifdef CONFIG_USB_GADGET_DEBUG_FS
85 
86 #include <linux/debugfs.h>
87 #include <linux/uaccess.h>
88 #include <linux/seq_file.h>
89 
90 static int state_dbg_show(struct seq_file *s, void *p)
91 {
92 	struct pxa_udc *udc = s->private;
93 	u32 tmp;
94 
95 	if (!udc->driver)
96 		return -ENODEV;
97 
98 	/* basic device status */
99 	seq_printf(s, DRIVER_DESC "\n"
100 		   "%s version: %s\n"
101 		   "Gadget driver: %s\n",
102 		   driver_name, DRIVER_VERSION,
103 		   udc->driver ? udc->driver->driver.name : "(none)");
104 
105 	tmp = udc_readl(udc, UDCCR);
106 	seq_printf(s,
107 		   "udccr=0x%0x(%s%s%s%s%s%s%s%s%s%s), con=%d,inter=%d,altinter=%d\n",
108 		   tmp,
109 		   (tmp & UDCCR_OEN) ? " oen":"",
110 		   (tmp & UDCCR_AALTHNP) ? " aalthnp":"",
111 		   (tmp & UDCCR_AHNP) ? " rem" : "",
112 		   (tmp & UDCCR_BHNP) ? " rstir" : "",
113 		   (tmp & UDCCR_DWRE) ? " dwre" : "",
114 		   (tmp & UDCCR_SMAC) ? " smac" : "",
115 		   (tmp & UDCCR_EMCE) ? " emce" : "",
116 		   (tmp & UDCCR_UDR) ? " udr" : "",
117 		   (tmp & UDCCR_UDA) ? " uda" : "",
118 		   (tmp & UDCCR_UDE) ? " ude" : "",
119 		   (tmp & UDCCR_ACN) >> UDCCR_ACN_S,
120 		   (tmp & UDCCR_AIN) >> UDCCR_AIN_S,
121 		   (tmp & UDCCR_AAISN) >> UDCCR_AAISN_S);
122 	/* registers for device and ep0 */
123 	seq_printf(s, "udcicr0=0x%08x udcicr1=0x%08x\n",
124 		   udc_readl(udc, UDCICR0), udc_readl(udc, UDCICR1));
125 	seq_printf(s, "udcisr0=0x%08x udcisr1=0x%08x\n",
126 		   udc_readl(udc, UDCISR0), udc_readl(udc, UDCISR1));
127 	seq_printf(s, "udcfnr=%d\n", udc_readl(udc, UDCFNR));
128 	seq_printf(s, "irqs: reset=%lu, suspend=%lu, resume=%lu, reconfig=%lu\n",
129 		   udc->stats.irqs_reset, udc->stats.irqs_suspend,
130 		   udc->stats.irqs_resume, udc->stats.irqs_reconfig);
131 
132 	return 0;
133 }
134 DEFINE_SHOW_ATTRIBUTE(state_dbg);
135 
136 static int queues_dbg_show(struct seq_file *s, void *p)
137 {
138 	struct pxa_udc *udc = s->private;
139 	struct pxa_ep *ep;
140 	struct pxa27x_request *req;
141 	int i, maxpkt;
142 
143 	if (!udc->driver)
144 		return -ENODEV;
145 
146 	/* dump endpoint queues */
147 	for (i = 0; i < NR_PXA_ENDPOINTS; i++) {
148 		ep = &udc->pxa_ep[i];
149 		maxpkt = ep->fifo_size;
150 		seq_printf(s,  "%-12s max_pkt=%d %s\n",
151 			   EPNAME(ep), maxpkt, "pio");
152 
153 		if (list_empty(&ep->queue)) {
154 			seq_puts(s, "\t(nothing queued)\n");
155 			continue;
156 		}
157 
158 		list_for_each_entry(req, &ep->queue, queue) {
159 			seq_printf(s,  "\treq %p len %d/%d buf %p\n",
160 				   &req->req, req->req.actual,
161 				   req->req.length, req->req.buf);
162 		}
163 	}
164 
165 	return 0;
166 }
167 DEFINE_SHOW_ATTRIBUTE(queues_dbg);
168 
169 static int eps_dbg_show(struct seq_file *s, void *p)
170 {
171 	struct pxa_udc *udc = s->private;
172 	struct pxa_ep *ep;
173 	int i;
174 	u32 tmp;
175 
176 	if (!udc->driver)
177 		return -ENODEV;
178 
179 	ep = &udc->pxa_ep[0];
180 	tmp = udc_ep_readl(ep, UDCCSR);
181 	seq_printf(s, "udccsr0=0x%03x(%s%s%s%s%s%s%s)\n",
182 		   tmp,
183 		   (tmp & UDCCSR0_SA) ? " sa" : "",
184 		   (tmp & UDCCSR0_RNE) ? " rne" : "",
185 		   (tmp & UDCCSR0_FST) ? " fst" : "",
186 		   (tmp & UDCCSR0_SST) ? " sst" : "",
187 		   (tmp & UDCCSR0_DME) ? " dme" : "",
188 		   (tmp & UDCCSR0_IPR) ? " ipr" : "",
189 		   (tmp & UDCCSR0_OPC) ? " opc" : "");
190 	for (i = 0; i < NR_PXA_ENDPOINTS; i++) {
191 		ep = &udc->pxa_ep[i];
192 		tmp = i? udc_ep_readl(ep, UDCCR) : udc_readl(udc, UDCCR);
193 		seq_printf(s, "%-12s: IN %lu(%lu reqs), OUT %lu(%lu reqs), irqs=%lu, udccr=0x%08x, udccsr=0x%03x, udcbcr=%d\n",
194 			   EPNAME(ep),
195 			   ep->stats.in_bytes, ep->stats.in_ops,
196 			   ep->stats.out_bytes, ep->stats.out_ops,
197 			   ep->stats.irqs,
198 			   tmp, udc_ep_readl(ep, UDCCSR),
199 			   udc_ep_readl(ep, UDCBCR));
200 	}
201 
202 	return 0;
203 }
204 DEFINE_SHOW_ATTRIBUTE(eps_dbg);
205 
206 static void pxa_init_debugfs(struct pxa_udc *udc)
207 {
208 	struct dentry *root;
209 
210 	root = debugfs_create_dir(udc->gadget.name, usb_debug_root);
211 	debugfs_create_file("udcstate", 0400, root, udc, &state_dbg_fops);
212 	debugfs_create_file("queues", 0400, root, udc, &queues_dbg_fops);
213 	debugfs_create_file("epstate", 0400, root, udc, &eps_dbg_fops);
214 }
215 
216 static void pxa_cleanup_debugfs(struct pxa_udc *udc)
217 {
218 	debugfs_lookup_and_remove(udc->gadget.name, usb_debug_root);
219 }
220 
221 #else
222 static inline void pxa_init_debugfs(struct pxa_udc *udc)
223 {
224 }
225 
226 static inline void pxa_cleanup_debugfs(struct pxa_udc *udc)
227 {
228 }
229 #endif
230 
231 /**
232  * is_match_usb_pxa - check if usb_ep and pxa_ep match
233  * @udc_usb_ep: usb endpoint
234  * @ep: pxa endpoint
235  * @config: configuration required in pxa_ep
236  * @interface: interface required in pxa_ep
237  * @altsetting: altsetting required in pxa_ep
238  *
239  * Returns 1 if all criteria match between pxa and usb endpoint, 0 otherwise
240  */
241 static int is_match_usb_pxa(struct udc_usb_ep *udc_usb_ep, struct pxa_ep *ep,
242 		int config, int interface, int altsetting)
243 {
244 	if (usb_endpoint_num(&udc_usb_ep->desc) != ep->addr)
245 		return 0;
246 	if (usb_endpoint_dir_in(&udc_usb_ep->desc) != ep->dir_in)
247 		return 0;
248 	if (usb_endpoint_type(&udc_usb_ep->desc) != ep->type)
249 		return 0;
250 	if ((ep->config != config) || (ep->interface != interface)
251 			|| (ep->alternate != altsetting))
252 		return 0;
253 	return 1;
254 }
255 
256 /**
257  * find_pxa_ep - find pxa_ep structure matching udc_usb_ep
258  * @udc: pxa udc
259  * @udc_usb_ep: udc_usb_ep structure
260  *
261  * Match udc_usb_ep and all pxa_ep available, to see if one matches.
262  * This is necessary because of the strong pxa hardware restriction requiring
263  * that once pxa endpoints are initialized, their configuration is freezed, and
264  * no change can be made to their address, direction, or in which configuration,
265  * interface or altsetting they are active ... which differs from more usual
266  * models which have endpoints be roughly just addressable fifos, and leave
267  * configuration events up to gadget drivers (like all control messages).
268  *
269  * Note that there is still a blurred point here :
270  *   - we rely on UDCCR register "active interface" and "active altsetting".
271  *     This is a nonsense in regard of USB spec, where multiple interfaces are
272  *     active at the same time.
273  *   - if we knew for sure that the pxa can handle multiple interface at the
274  *     same time, assuming Intel's Developer Guide is wrong, this function
275  *     should be reviewed, and a cache of couples (iface, altsetting) should
276  *     be kept in the pxa_udc structure. In this case this function would match
277  *     against the cache of couples instead of the "last altsetting" set up.
278  *
279  * Returns the matched pxa_ep structure or NULL if none found
280  */
281 static struct pxa_ep *find_pxa_ep(struct pxa_udc *udc,
282 		struct udc_usb_ep *udc_usb_ep)
283 {
284 	int i;
285 	struct pxa_ep *ep;
286 	int cfg = udc->config;
287 	int iface = udc->last_interface;
288 	int alt = udc->last_alternate;
289 
290 	if (udc_usb_ep == &udc->udc_usb_ep[0])
291 		return &udc->pxa_ep[0];
292 
293 	for (i = 1; i < NR_PXA_ENDPOINTS; i++) {
294 		ep = &udc->pxa_ep[i];
295 		if (is_match_usb_pxa(udc_usb_ep, ep, cfg, iface, alt))
296 			return ep;
297 	}
298 	return NULL;
299 }
300 
301 /**
302  * update_pxa_ep_matches - update pxa_ep cached values in all udc_usb_ep
303  * @udc: pxa udc
304  *
305  * Context: interrupt handler
306  *
307  * Updates all pxa_ep fields in udc_usb_ep structures, if this field was
308  * previously set up (and is not NULL). The update is necessary is a
309  * configuration change or altsetting change was issued by the USB host.
310  */
311 static void update_pxa_ep_matches(struct pxa_udc *udc)
312 {
313 	int i;
314 	struct udc_usb_ep *udc_usb_ep;
315 
316 	for (i = 1; i < NR_USB_ENDPOINTS; i++) {
317 		udc_usb_ep = &udc->udc_usb_ep[i];
318 		if (udc_usb_ep->pxa_ep)
319 			udc_usb_ep->pxa_ep = find_pxa_ep(udc, udc_usb_ep);
320 	}
321 }
322 
323 /**
324  * pio_irq_enable - Enables irq generation for one endpoint
325  * @ep: udc endpoint
326  */
327 static void pio_irq_enable(struct pxa_ep *ep)
328 {
329 	struct pxa_udc *udc = ep->dev;
330 	int index = EPIDX(ep);
331 	u32 udcicr0 = udc_readl(udc, UDCICR0);
332 	u32 udcicr1 = udc_readl(udc, UDCICR1);
333 
334 	if (index < 16)
335 		udc_writel(udc, UDCICR0, udcicr0 | (3 << (index * 2)));
336 	else
337 		udc_writel(udc, UDCICR1, udcicr1 | (3 << ((index - 16) * 2)));
338 }
339 
340 /**
341  * pio_irq_disable - Disables irq generation for one endpoint
342  * @ep: udc endpoint
343  */
344 static void pio_irq_disable(struct pxa_ep *ep)
345 {
346 	struct pxa_udc *udc = ep->dev;
347 	int index = EPIDX(ep);
348 	u32 udcicr0 = udc_readl(udc, UDCICR0);
349 	u32 udcicr1 = udc_readl(udc, UDCICR1);
350 
351 	if (index < 16)
352 		udc_writel(udc, UDCICR0, udcicr0 & ~(3 << (index * 2)));
353 	else
354 		udc_writel(udc, UDCICR1, udcicr1 & ~(3 << ((index - 16) * 2)));
355 }
356 
357 /**
358  * udc_set_mask_UDCCR - set bits in UDCCR
359  * @udc: udc device
360  * @mask: bits to set in UDCCR
361  *
362  * Sets bits in UDCCR, leaving DME and FST bits as they were.
363  */
364 static inline void udc_set_mask_UDCCR(struct pxa_udc *udc, int mask)
365 {
366 	u32 udccr = udc_readl(udc, UDCCR);
367 	udc_writel(udc, UDCCR,
368 			(udccr & UDCCR_MASK_BITS) | (mask & UDCCR_MASK_BITS));
369 }
370 
371 /**
372  * udc_clear_mask_UDCCR - clears bits in UDCCR
373  * @udc: udc device
374  * @mask: bit to clear in UDCCR
375  *
376  * Clears bits in UDCCR, leaving DME and FST bits as they were.
377  */
378 static inline void udc_clear_mask_UDCCR(struct pxa_udc *udc, int mask)
379 {
380 	u32 udccr = udc_readl(udc, UDCCR);
381 	udc_writel(udc, UDCCR,
382 			(udccr & UDCCR_MASK_BITS) & ~(mask & UDCCR_MASK_BITS));
383 }
384 
385 /**
386  * ep_write_UDCCSR - set bits in UDCCSR
387  * @ep: udc endpoint
388  * @mask: bits to set in UDCCR
389  *
390  * Sets bits in UDCCSR (UDCCSR0 and UDCCSR*).
391  *
392  * A specific case is applied to ep0 : the ACM bit is always set to 1, for
393  * SET_INTERFACE and SET_CONFIGURATION.
394  */
395 static inline void ep_write_UDCCSR(struct pxa_ep *ep, int mask)
396 {
397 	if (is_ep0(ep))
398 		mask |= UDCCSR0_ACM;
399 	udc_ep_writel(ep, UDCCSR, mask);
400 }
401 
402 /**
403  * ep_count_bytes_remain - get how many bytes in udc endpoint
404  * @ep: udc endpoint
405  *
406  * Returns number of bytes in OUT fifos. Broken for IN fifos (-EOPNOTSUPP)
407  */
408 static int ep_count_bytes_remain(struct pxa_ep *ep)
409 {
410 	if (ep->dir_in)
411 		return -EOPNOTSUPP;
412 	return udc_ep_readl(ep, UDCBCR) & 0x3ff;
413 }
414 
415 /**
416  * ep_is_empty - checks if ep has byte ready for reading
417  * @ep: udc endpoint
418  *
419  * If endpoint is the control endpoint, checks if there are bytes in the
420  * control endpoint fifo. If endpoint is a data endpoint, checks if bytes
421  * are ready for reading on OUT endpoint.
422  *
423  * Returns 0 if ep not empty, 1 if ep empty, -EOPNOTSUPP if IN endpoint
424  */
425 static int ep_is_empty(struct pxa_ep *ep)
426 {
427 	int ret;
428 
429 	if (!is_ep0(ep) && ep->dir_in)
430 		return -EOPNOTSUPP;
431 	if (is_ep0(ep))
432 		ret = !(udc_ep_readl(ep, UDCCSR) & UDCCSR0_RNE);
433 	else
434 		ret = !(udc_ep_readl(ep, UDCCSR) & UDCCSR_BNE);
435 	return ret;
436 }
437 
438 /**
439  * ep_is_full - checks if ep has place to write bytes
440  * @ep: udc endpoint
441  *
442  * If endpoint is not the control endpoint and is an IN endpoint, checks if
443  * there is place to write bytes into the endpoint.
444  *
445  * Returns 0 if ep not full, 1 if ep full, -EOPNOTSUPP if OUT endpoint
446  */
447 static int ep_is_full(struct pxa_ep *ep)
448 {
449 	if (is_ep0(ep))
450 		return (udc_ep_readl(ep, UDCCSR) & UDCCSR0_IPR);
451 	if (!ep->dir_in)
452 		return -EOPNOTSUPP;
453 	return (!(udc_ep_readl(ep, UDCCSR) & UDCCSR_BNF));
454 }
455 
456 /**
457  * epout_has_pkt - checks if OUT endpoint fifo has a packet available
458  * @ep: pxa endpoint
459  *
460  * Returns 1 if a complete packet is available, 0 if not, -EOPNOTSUPP for IN ep.
461  */
462 static int epout_has_pkt(struct pxa_ep *ep)
463 {
464 	if (!is_ep0(ep) && ep->dir_in)
465 		return -EOPNOTSUPP;
466 	if (is_ep0(ep))
467 		return (udc_ep_readl(ep, UDCCSR) & UDCCSR0_OPC);
468 	return (udc_ep_readl(ep, UDCCSR) & UDCCSR_PC);
469 }
470 
471 /**
472  * set_ep0state - Set ep0 automata state
473  * @udc: udc device
474  * @state: state
475  */
476 static void set_ep0state(struct pxa_udc *udc, int state)
477 {
478 	struct pxa_ep *ep = &udc->pxa_ep[0];
479 	char *old_stname = EP0_STNAME(udc);
480 
481 	udc->ep0state = state;
482 	ep_dbg(ep, "state=%s->%s, udccsr0=0x%03x, udcbcr=%d\n", old_stname,
483 		EP0_STNAME(udc), udc_ep_readl(ep, UDCCSR),
484 		udc_ep_readl(ep, UDCBCR));
485 }
486 
487 /**
488  * ep0_idle - Put control endpoint into idle state
489  * @dev: udc device
490  */
491 static void ep0_idle(struct pxa_udc *dev)
492 {
493 	set_ep0state(dev, WAIT_FOR_SETUP);
494 }
495 
496 /**
497  * inc_ep_stats_reqs - Update ep stats counts
498  * @ep: physical endpoint
499  * @is_in: ep direction (USB_DIR_IN or 0)
500  *
501  */
502 static void inc_ep_stats_reqs(struct pxa_ep *ep, int is_in)
503 {
504 	if (is_in)
505 		ep->stats.in_ops++;
506 	else
507 		ep->stats.out_ops++;
508 }
509 
510 /**
511  * inc_ep_stats_bytes - Update ep stats counts
512  * @ep: physical endpoint
513  * @count: bytes transferred on endpoint
514  * @is_in: ep direction (USB_DIR_IN or 0)
515  */
516 static void inc_ep_stats_bytes(struct pxa_ep *ep, int count, int is_in)
517 {
518 	if (is_in)
519 		ep->stats.in_bytes += count;
520 	else
521 		ep->stats.out_bytes += count;
522 }
523 
524 /**
525  * pxa_ep_setup - Sets up an usb physical endpoint
526  * @ep: pxa27x physical endpoint
527  *
528  * Find the physical pxa27x ep, and setup its UDCCR
529  */
530 static void pxa_ep_setup(struct pxa_ep *ep)
531 {
532 	u32 new_udccr;
533 
534 	new_udccr = ((ep->config << UDCCONR_CN_S) & UDCCONR_CN)
535 		| ((ep->interface << UDCCONR_IN_S) & UDCCONR_IN)
536 		| ((ep->alternate << UDCCONR_AISN_S) & UDCCONR_AISN)
537 		| ((EPADDR(ep) << UDCCONR_EN_S) & UDCCONR_EN)
538 		| ((EPXFERTYPE(ep) << UDCCONR_ET_S) & UDCCONR_ET)
539 		| ((ep->dir_in) ? UDCCONR_ED : 0)
540 		| ((ep->fifo_size << UDCCONR_MPS_S) & UDCCONR_MPS)
541 		| UDCCONR_EE;
542 
543 	udc_ep_writel(ep, UDCCR, new_udccr);
544 }
545 
546 /**
547  * pxa_eps_setup - Sets up all usb physical endpoints
548  * @dev: udc device
549  *
550  * Setup all pxa physical endpoints, except ep0
551  */
552 static void pxa_eps_setup(struct pxa_udc *dev)
553 {
554 	unsigned int i;
555 
556 	dev_dbg(dev->dev, "%s: dev=%p\n", __func__, dev);
557 
558 	for (i = 1; i < NR_PXA_ENDPOINTS; i++)
559 		pxa_ep_setup(&dev->pxa_ep[i]);
560 }
561 
562 /**
563  * pxa_ep_alloc_request - Allocate usb request
564  * @_ep: usb endpoint
565  * @gfp_flags:
566  *
567  * For the pxa27x, these can just wrap kmalloc/kfree.  gadget drivers
568  * must still pass correctly initialized endpoints, since other controller
569  * drivers may care about how it's currently set up (dma issues etc).
570   */
571 static struct usb_request *
572 pxa_ep_alloc_request(struct usb_ep *_ep, gfp_t gfp_flags)
573 {
574 	struct pxa27x_request *req;
575 
576 	req = kzalloc(sizeof *req, gfp_flags);
577 	if (!req)
578 		return NULL;
579 
580 	INIT_LIST_HEAD(&req->queue);
581 	req->in_use = 0;
582 	req->udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
583 
584 	return &req->req;
585 }
586 
587 /**
588  * pxa_ep_free_request - Free usb request
589  * @_ep: usb endpoint
590  * @_req: usb request
591  *
592  * Wrapper around kfree to free _req
593  */
594 static void pxa_ep_free_request(struct usb_ep *_ep, struct usb_request *_req)
595 {
596 	struct pxa27x_request *req;
597 
598 	req = container_of(_req, struct pxa27x_request, req);
599 	WARN_ON(!list_empty(&req->queue));
600 	kfree(req);
601 }
602 
603 /**
604  * ep_add_request - add a request to the endpoint's queue
605  * @ep: usb endpoint
606  * @req: usb request
607  *
608  * Context: ep->lock held
609  *
610  * Queues the request in the endpoint's queue, and enables the interrupts
611  * on the endpoint.
612  */
613 static void ep_add_request(struct pxa_ep *ep, struct pxa27x_request *req)
614 {
615 	if (unlikely(!req))
616 		return;
617 	ep_vdbg(ep, "req:%p, lg=%d, udccsr=0x%03x\n", req,
618 		req->req.length, udc_ep_readl(ep, UDCCSR));
619 
620 	req->in_use = 1;
621 	list_add_tail(&req->queue, &ep->queue);
622 	pio_irq_enable(ep);
623 }
624 
625 /**
626  * ep_del_request - removes a request from the endpoint's queue
627  * @ep: usb endpoint
628  * @req: usb request
629  *
630  * Context: ep->lock held
631  *
632  * Unqueue the request from the endpoint's queue. If there are no more requests
633  * on the endpoint, and if it's not the control endpoint, interrupts are
634  * disabled on the endpoint.
635  */
636 static void ep_del_request(struct pxa_ep *ep, struct pxa27x_request *req)
637 {
638 	if (unlikely(!req))
639 		return;
640 	ep_vdbg(ep, "req:%p, lg=%d, udccsr=0x%03x\n", req,
641 		req->req.length, udc_ep_readl(ep, UDCCSR));
642 
643 	list_del_init(&req->queue);
644 	req->in_use = 0;
645 	if (!is_ep0(ep) && list_empty(&ep->queue))
646 		pio_irq_disable(ep);
647 }
648 
649 /**
650  * req_done - Complete an usb request
651  * @ep: pxa physical endpoint
652  * @req: pxa request
653  * @status: usb request status sent to gadget API
654  * @pflags: flags of previous spinlock_irq_save() or NULL if no lock held
655  *
656  * Context: ep->lock held if flags not NULL, else ep->lock released
657  *
658  * Retire a pxa27x usb request. Endpoint must be locked.
659  */
660 static void req_done(struct pxa_ep *ep, struct pxa27x_request *req, int status,
661 	unsigned long *pflags)
662 {
663 	unsigned long	flags;
664 
665 	ep_del_request(ep, req);
666 	if (likely(req->req.status == -EINPROGRESS))
667 		req->req.status = status;
668 	else
669 		status = req->req.status;
670 
671 	if (status && status != -ESHUTDOWN)
672 		ep_dbg(ep, "complete req %p stat %d len %u/%u\n",
673 			&req->req, status,
674 			req->req.actual, req->req.length);
675 
676 	if (pflags)
677 		spin_unlock_irqrestore(&ep->lock, *pflags);
678 	local_irq_save(flags);
679 	usb_gadget_giveback_request(&req->udc_usb_ep->usb_ep, &req->req);
680 	local_irq_restore(flags);
681 	if (pflags)
682 		spin_lock_irqsave(&ep->lock, *pflags);
683 }
684 
685 /**
686  * ep_end_out_req - Ends endpoint OUT request
687  * @ep: physical endpoint
688  * @req: pxa request
689  * @pflags: flags of previous spinlock_irq_save() or NULL if no lock held
690  *
691  * Context: ep->lock held or released (see req_done())
692  *
693  * Ends endpoint OUT request (completes usb request).
694  */
695 static void ep_end_out_req(struct pxa_ep *ep, struct pxa27x_request *req,
696 	unsigned long *pflags)
697 {
698 	inc_ep_stats_reqs(ep, !USB_DIR_IN);
699 	req_done(ep, req, 0, pflags);
700 }
701 
702 /**
703  * ep0_end_out_req - Ends control endpoint OUT request (ends data stage)
704  * @ep: physical endpoint
705  * @req: pxa request
706  * @pflags: flags of previous spinlock_irq_save() or NULL if no lock held
707  *
708  * Context: ep->lock held or released (see req_done())
709  *
710  * Ends control endpoint OUT request (completes usb request), and puts
711  * control endpoint into idle state
712  */
713 static void ep0_end_out_req(struct pxa_ep *ep, struct pxa27x_request *req,
714 	unsigned long *pflags)
715 {
716 	set_ep0state(ep->dev, OUT_STATUS_STAGE);
717 	ep_end_out_req(ep, req, pflags);
718 	ep0_idle(ep->dev);
719 }
720 
721 /**
722  * ep_end_in_req - Ends endpoint IN request
723  * @ep: physical endpoint
724  * @req: pxa request
725  * @pflags: flags of previous spinlock_irq_save() or NULL if no lock held
726  *
727  * Context: ep->lock held or released (see req_done())
728  *
729  * Ends endpoint IN request (completes usb request).
730  */
731 static void ep_end_in_req(struct pxa_ep *ep, struct pxa27x_request *req,
732 	unsigned long *pflags)
733 {
734 	inc_ep_stats_reqs(ep, USB_DIR_IN);
735 	req_done(ep, req, 0, pflags);
736 }
737 
738 /**
739  * ep0_end_in_req - Ends control endpoint IN request (ends data stage)
740  * @ep: physical endpoint
741  * @req: pxa request
742  * @pflags: flags of previous spinlock_irq_save() or NULL if no lock held
743  *
744  * Context: ep->lock held or released (see req_done())
745  *
746  * Ends control endpoint IN request (completes usb request), and puts
747  * control endpoint into status state
748  */
749 static void ep0_end_in_req(struct pxa_ep *ep, struct pxa27x_request *req,
750 	unsigned long *pflags)
751 {
752 	set_ep0state(ep->dev, IN_STATUS_STAGE);
753 	ep_end_in_req(ep, req, pflags);
754 }
755 
756 /**
757  * nuke - Dequeue all requests
758  * @ep: pxa endpoint
759  * @status: usb request status
760  *
761  * Context: ep->lock released
762  *
763  * Dequeues all requests on an endpoint. As a side effect, interrupts will be
764  * disabled on that endpoint (because no more requests).
765  */
766 static void nuke(struct pxa_ep *ep, int status)
767 {
768 	struct pxa27x_request	*req;
769 	unsigned long		flags;
770 
771 	spin_lock_irqsave(&ep->lock, flags);
772 	while (!list_empty(&ep->queue)) {
773 		req = list_entry(ep->queue.next, struct pxa27x_request, queue);
774 		req_done(ep, req, status, &flags);
775 	}
776 	spin_unlock_irqrestore(&ep->lock, flags);
777 }
778 
779 /**
780  * read_packet - transfer 1 packet from an OUT endpoint into request
781  * @ep: pxa physical endpoint
782  * @req: usb request
783  *
784  * Takes bytes from OUT endpoint and transfers them info the usb request.
785  * If there is less space in request than bytes received in OUT endpoint,
786  * bytes are left in the OUT endpoint.
787  *
788  * Returns how many bytes were actually transferred
789  */
790 static int read_packet(struct pxa_ep *ep, struct pxa27x_request *req)
791 {
792 	u32 *buf;
793 	int bytes_ep, bufferspace, count, i;
794 
795 	bytes_ep = ep_count_bytes_remain(ep);
796 	bufferspace = req->req.length - req->req.actual;
797 
798 	buf = (u32 *)(req->req.buf + req->req.actual);
799 	prefetchw(buf);
800 
801 	if (likely(!ep_is_empty(ep)))
802 		count = min(bytes_ep, bufferspace);
803 	else /* zlp */
804 		count = 0;
805 
806 	for (i = count; i > 0; i -= 4)
807 		*buf++ = udc_ep_readl(ep, UDCDR);
808 	req->req.actual += count;
809 
810 	ep_write_UDCCSR(ep, UDCCSR_PC);
811 
812 	return count;
813 }
814 
815 /**
816  * write_packet - transfer 1 packet from request into an IN endpoint
817  * @ep: pxa physical endpoint
818  * @req: usb request
819  * @max: max bytes that fit into endpoint
820  *
821  * Takes bytes from usb request, and transfers them into the physical
822  * endpoint. If there are no bytes to transfer, doesn't write anything
823  * to physical endpoint.
824  *
825  * Returns how many bytes were actually transferred.
826  */
827 static int write_packet(struct pxa_ep *ep, struct pxa27x_request *req,
828 			unsigned int max)
829 {
830 	int length, count, remain, i;
831 	u32 *buf;
832 	u8 *buf_8;
833 
834 	buf = (u32 *)(req->req.buf + req->req.actual);
835 	prefetch(buf);
836 
837 	length = min(req->req.length - req->req.actual, max);
838 	req->req.actual += length;
839 
840 	remain = length & 0x3;
841 	count = length & ~(0x3);
842 	for (i = count; i > 0 ; i -= 4)
843 		udc_ep_writel(ep, UDCDR, *buf++);
844 
845 	buf_8 = (u8 *)buf;
846 	for (i = remain; i > 0; i--)
847 		udc_ep_writeb(ep, UDCDR, *buf_8++);
848 
849 	ep_vdbg(ep, "length=%d+%d, udccsr=0x%03x\n", count, remain,
850 		udc_ep_readl(ep, UDCCSR));
851 
852 	return length;
853 }
854 
855 /**
856  * read_fifo - Transfer packets from OUT endpoint into usb request
857  * @ep: pxa physical endpoint
858  * @req: usb request
859  *
860  * Context: interrupt handler
861  *
862  * Unload as many packets as possible from the fifo we use for usb OUT
863  * transfers and put them into the request. Caller should have made sure
864  * there's at least one packet ready.
865  * Doesn't complete the request, that's the caller's job
866  *
867  * Returns 1 if the request completed, 0 otherwise
868  */
869 static int read_fifo(struct pxa_ep *ep, struct pxa27x_request *req)
870 {
871 	int count, is_short, completed = 0;
872 
873 	while (epout_has_pkt(ep)) {
874 		count = read_packet(ep, req);
875 		inc_ep_stats_bytes(ep, count, !USB_DIR_IN);
876 
877 		is_short = (count < ep->fifo_size);
878 		ep_dbg(ep, "read udccsr:%03x, count:%d bytes%s req %p %d/%d\n",
879 			udc_ep_readl(ep, UDCCSR), count, is_short ? "/S" : "",
880 			&req->req, req->req.actual, req->req.length);
881 
882 		/* completion */
883 		if (is_short || req->req.actual == req->req.length) {
884 			completed = 1;
885 			break;
886 		}
887 		/* finished that packet.  the next one may be waiting... */
888 	}
889 	return completed;
890 }
891 
892 /**
893  * write_fifo - transfer packets from usb request into an IN endpoint
894  * @ep: pxa physical endpoint
895  * @req: pxa usb request
896  *
897  * Write to an IN endpoint fifo, as many packets as possible.
898  * irqs will use this to write the rest later.
899  * caller guarantees at least one packet buffer is ready (or a zlp).
900  * Doesn't complete the request, that's the caller's job
901  *
902  * Returns 1 if request fully transferred, 0 if partial transfer
903  */
904 static int write_fifo(struct pxa_ep *ep, struct pxa27x_request *req)
905 {
906 	unsigned max;
907 	int count, is_short, is_last = 0, completed = 0, totcount = 0;
908 	u32 udccsr;
909 
910 	max = ep->fifo_size;
911 	do {
912 		udccsr = udc_ep_readl(ep, UDCCSR);
913 		if (udccsr & UDCCSR_PC) {
914 			ep_vdbg(ep, "Clearing Transmit Complete, udccsr=%x\n",
915 				udccsr);
916 			ep_write_UDCCSR(ep, UDCCSR_PC);
917 		}
918 		if (udccsr & UDCCSR_TRN) {
919 			ep_vdbg(ep, "Clearing Underrun on, udccsr=%x\n",
920 				udccsr);
921 			ep_write_UDCCSR(ep, UDCCSR_TRN);
922 		}
923 
924 		count = write_packet(ep, req, max);
925 		inc_ep_stats_bytes(ep, count, USB_DIR_IN);
926 		totcount += count;
927 
928 		/* last packet is usually short (or a zlp) */
929 		if (unlikely(count < max)) {
930 			is_last = 1;
931 			is_short = 1;
932 		} else {
933 			if (likely(req->req.length > req->req.actual)
934 					|| req->req.zero)
935 				is_last = 0;
936 			else
937 				is_last = 1;
938 			/* interrupt/iso maxpacket may not fill the fifo */
939 			is_short = unlikely(max < ep->fifo_size);
940 		}
941 
942 		if (is_short)
943 			ep_write_UDCCSR(ep, UDCCSR_SP);
944 
945 		/* requests complete when all IN data is in the FIFO */
946 		if (is_last) {
947 			completed = 1;
948 			break;
949 		}
950 	} while (!ep_is_full(ep));
951 
952 	ep_dbg(ep, "wrote count:%d bytes%s%s, left:%d req=%p\n",
953 			totcount, is_last ? "/L" : "", is_short ? "/S" : "",
954 			req->req.length - req->req.actual, &req->req);
955 
956 	return completed;
957 }
958 
959 /**
960  * read_ep0_fifo - Transfer packets from control endpoint into usb request
961  * @ep: control endpoint
962  * @req: pxa usb request
963  *
964  * Special ep0 version of the above read_fifo. Reads as many bytes from control
965  * endpoint as can be read, and stores them into usb request (limited by request
966  * maximum length).
967  *
968  * Returns 0 if usb request only partially filled, 1 if fully filled
969  */
970 static int read_ep0_fifo(struct pxa_ep *ep, struct pxa27x_request *req)
971 {
972 	int count, is_short, completed = 0;
973 
974 	while (epout_has_pkt(ep)) {
975 		count = read_packet(ep, req);
976 		ep_write_UDCCSR(ep, UDCCSR0_OPC);
977 		inc_ep_stats_bytes(ep, count, !USB_DIR_IN);
978 
979 		is_short = (count < ep->fifo_size);
980 		ep_dbg(ep, "read udccsr:%03x, count:%d bytes%s req %p %d/%d\n",
981 			udc_ep_readl(ep, UDCCSR), count, is_short ? "/S" : "",
982 			&req->req, req->req.actual, req->req.length);
983 
984 		if (is_short || req->req.actual >= req->req.length) {
985 			completed = 1;
986 			break;
987 		}
988 	}
989 
990 	return completed;
991 }
992 
993 /**
994  * write_ep0_fifo - Send a request to control endpoint (ep0 in)
995  * @ep: control endpoint
996  * @req: request
997  *
998  * Context: interrupt handler
999  *
1000  * Sends a request (or a part of the request) to the control endpoint (ep0 in).
1001  * If the request doesn't fit, the remaining part will be sent from irq.
1002  * The request is considered fully written only if either :
1003  *   - last write transferred all remaining bytes, but fifo was not fully filled
1004  *   - last write was a 0 length write
1005  *
1006  * Returns 1 if request fully written, 0 if request only partially sent
1007  */
1008 static int write_ep0_fifo(struct pxa_ep *ep, struct pxa27x_request *req)
1009 {
1010 	unsigned	count;
1011 	int		is_last, is_short;
1012 
1013 	count = write_packet(ep, req, EP0_FIFO_SIZE);
1014 	inc_ep_stats_bytes(ep, count, USB_DIR_IN);
1015 
1016 	is_short = (count < EP0_FIFO_SIZE);
1017 	is_last = ((count == 0) || (count < EP0_FIFO_SIZE));
1018 
1019 	/* Sends either a short packet or a 0 length packet */
1020 	if (unlikely(is_short))
1021 		ep_write_UDCCSR(ep, UDCCSR0_IPR);
1022 
1023 	ep_dbg(ep, "in %d bytes%s%s, %d left, req=%p, udccsr0=0x%03x\n",
1024 		count, is_short ? "/S" : "", is_last ? "/L" : "",
1025 		req->req.length - req->req.actual,
1026 		&req->req, udc_ep_readl(ep, UDCCSR));
1027 
1028 	return is_last;
1029 }
1030 
1031 /**
1032  * pxa_ep_queue - Queue a request into an IN endpoint
1033  * @_ep: usb endpoint
1034  * @_req: usb request
1035  * @gfp_flags: flags
1036  *
1037  * Context: thread context or from the interrupt handler in the
1038  * special case of ep0 setup :
1039  *   (irq->handle_ep0_ctrl_req->gadget_setup->pxa_ep_queue)
1040  *
1041  * Returns 0 if succedeed, error otherwise
1042  */
1043 static int pxa_ep_queue(struct usb_ep *_ep, struct usb_request *_req,
1044 			gfp_t gfp_flags)
1045 {
1046 	struct udc_usb_ep	*udc_usb_ep;
1047 	struct pxa_ep		*ep;
1048 	struct pxa27x_request	*req;
1049 	struct pxa_udc		*dev;
1050 	unsigned long		flags;
1051 	int			rc = 0;
1052 	int			is_first_req;
1053 	unsigned		length;
1054 	int			recursion_detected;
1055 
1056 	req = container_of(_req, struct pxa27x_request, req);
1057 	udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
1058 
1059 	if (unlikely(!_req || !_req->complete || !_req->buf))
1060 		return -EINVAL;
1061 
1062 	if (unlikely(!_ep))
1063 		return -EINVAL;
1064 
1065 	ep = udc_usb_ep->pxa_ep;
1066 	if (unlikely(!ep))
1067 		return -EINVAL;
1068 
1069 	dev = ep->dev;
1070 	if (unlikely(!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN)) {
1071 		ep_dbg(ep, "bogus device state\n");
1072 		return -ESHUTDOWN;
1073 	}
1074 
1075 	/* iso is always one packet per request, that's the only way
1076 	 * we can report per-packet status.  that also helps with dma.
1077 	 */
1078 	if (unlikely(EPXFERTYPE_is_ISO(ep)
1079 			&& req->req.length > ep->fifo_size))
1080 		return -EMSGSIZE;
1081 
1082 	spin_lock_irqsave(&ep->lock, flags);
1083 	recursion_detected = ep->in_handle_ep;
1084 
1085 	is_first_req = list_empty(&ep->queue);
1086 	ep_dbg(ep, "queue req %p(first=%s), len %d buf %p\n",
1087 			_req, is_first_req ? "yes" : "no",
1088 			_req->length, _req->buf);
1089 
1090 	if (!ep->enabled) {
1091 		_req->status = -ESHUTDOWN;
1092 		rc = -ESHUTDOWN;
1093 		goto out_locked;
1094 	}
1095 
1096 	if (req->in_use) {
1097 		ep_err(ep, "refusing to queue req %p (already queued)\n", req);
1098 		goto out_locked;
1099 	}
1100 
1101 	length = _req->length;
1102 	_req->status = -EINPROGRESS;
1103 	_req->actual = 0;
1104 
1105 	ep_add_request(ep, req);
1106 	spin_unlock_irqrestore(&ep->lock, flags);
1107 
1108 	if (is_ep0(ep)) {
1109 		switch (dev->ep0state) {
1110 		case WAIT_ACK_SET_CONF_INTERF:
1111 			if (length == 0) {
1112 				ep_end_in_req(ep, req, NULL);
1113 			} else {
1114 				ep_err(ep, "got a request of %d bytes while"
1115 					"in state WAIT_ACK_SET_CONF_INTERF\n",
1116 					length);
1117 				ep_del_request(ep, req);
1118 				rc = -EL2HLT;
1119 			}
1120 			ep0_idle(ep->dev);
1121 			break;
1122 		case IN_DATA_STAGE:
1123 			if (!ep_is_full(ep))
1124 				if (write_ep0_fifo(ep, req))
1125 					ep0_end_in_req(ep, req, NULL);
1126 			break;
1127 		case OUT_DATA_STAGE:
1128 			if ((length == 0) || !epout_has_pkt(ep))
1129 				if (read_ep0_fifo(ep, req))
1130 					ep0_end_out_req(ep, req, NULL);
1131 			break;
1132 		default:
1133 			ep_err(ep, "odd state %s to send me a request\n",
1134 				EP0_STNAME(ep->dev));
1135 			ep_del_request(ep, req);
1136 			rc = -EL2HLT;
1137 			break;
1138 		}
1139 	} else {
1140 		if (!recursion_detected)
1141 			handle_ep(ep);
1142 	}
1143 
1144 out:
1145 	return rc;
1146 out_locked:
1147 	spin_unlock_irqrestore(&ep->lock, flags);
1148 	goto out;
1149 }
1150 
1151 /**
1152  * pxa_ep_dequeue - Dequeue one request
1153  * @_ep: usb endpoint
1154  * @_req: usb request
1155  *
1156  * Return 0 if no error, -EINVAL or -ECONNRESET otherwise
1157  */
1158 static int pxa_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
1159 {
1160 	struct pxa_ep		*ep;
1161 	struct udc_usb_ep	*udc_usb_ep;
1162 	struct pxa27x_request	*req = NULL, *iter;
1163 	unsigned long		flags;
1164 	int			rc = -EINVAL;
1165 
1166 	if (!_ep)
1167 		return rc;
1168 	udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
1169 	ep = udc_usb_ep->pxa_ep;
1170 	if (!ep || is_ep0(ep))
1171 		return rc;
1172 
1173 	spin_lock_irqsave(&ep->lock, flags);
1174 
1175 	/* make sure it's actually queued on this endpoint */
1176 	list_for_each_entry(iter, &ep->queue, queue) {
1177 		if (&iter->req != _req)
1178 			continue;
1179 		req = iter;
1180 		rc = 0;
1181 		break;
1182 	}
1183 
1184 	spin_unlock_irqrestore(&ep->lock, flags);
1185 	if (!rc)
1186 		req_done(ep, req, -ECONNRESET, NULL);
1187 	return rc;
1188 }
1189 
1190 /**
1191  * pxa_ep_set_halt - Halts operations on one endpoint
1192  * @_ep: usb endpoint
1193  * @value:
1194  *
1195  * Returns 0 if no error, -EINVAL, -EROFS, -EAGAIN otherwise
1196  */
1197 static int pxa_ep_set_halt(struct usb_ep *_ep, int value)
1198 {
1199 	struct pxa_ep		*ep;
1200 	struct udc_usb_ep	*udc_usb_ep;
1201 	unsigned long flags;
1202 	int rc;
1203 
1204 
1205 	if (!_ep)
1206 		return -EINVAL;
1207 	udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
1208 	ep = udc_usb_ep->pxa_ep;
1209 	if (!ep || is_ep0(ep))
1210 		return -EINVAL;
1211 
1212 	if (value == 0) {
1213 		/*
1214 		 * This path (reset toggle+halt) is needed to implement
1215 		 * SET_INTERFACE on normal hardware.  but it can't be
1216 		 * done from software on the PXA UDC, and the hardware
1217 		 * forgets to do it as part of SET_INTERFACE automagic.
1218 		 */
1219 		ep_dbg(ep, "only host can clear halt\n");
1220 		return -EROFS;
1221 	}
1222 
1223 	spin_lock_irqsave(&ep->lock, flags);
1224 
1225 	rc = -EAGAIN;
1226 	if (ep->dir_in	&& (ep_is_full(ep) || !list_empty(&ep->queue)))
1227 		goto out;
1228 
1229 	/* FST, FEF bits are the same for control and non control endpoints */
1230 	rc = 0;
1231 	ep_write_UDCCSR(ep, UDCCSR_FST | UDCCSR_FEF);
1232 	if (is_ep0(ep))
1233 		set_ep0state(ep->dev, STALL);
1234 
1235 out:
1236 	spin_unlock_irqrestore(&ep->lock, flags);
1237 	return rc;
1238 }
1239 
1240 /**
1241  * pxa_ep_fifo_status - Get how many bytes in physical endpoint
1242  * @_ep: usb endpoint
1243  *
1244  * Returns number of bytes in OUT fifos. Broken for IN fifos.
1245  */
1246 static int pxa_ep_fifo_status(struct usb_ep *_ep)
1247 {
1248 	struct pxa_ep		*ep;
1249 	struct udc_usb_ep	*udc_usb_ep;
1250 
1251 	if (!_ep)
1252 		return -ENODEV;
1253 	udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
1254 	ep = udc_usb_ep->pxa_ep;
1255 	if (!ep || is_ep0(ep))
1256 		return -ENODEV;
1257 
1258 	if (ep->dir_in)
1259 		return -EOPNOTSUPP;
1260 	if (ep->dev->gadget.speed == USB_SPEED_UNKNOWN || ep_is_empty(ep))
1261 		return 0;
1262 	else
1263 		return ep_count_bytes_remain(ep) + 1;
1264 }
1265 
1266 /**
1267  * pxa_ep_fifo_flush - Flushes one endpoint
1268  * @_ep: usb endpoint
1269  *
1270  * Discards all data in one endpoint(IN or OUT), except control endpoint.
1271  */
1272 static void pxa_ep_fifo_flush(struct usb_ep *_ep)
1273 {
1274 	struct pxa_ep		*ep;
1275 	struct udc_usb_ep	*udc_usb_ep;
1276 	unsigned long		flags;
1277 
1278 	if (!_ep)
1279 		return;
1280 	udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
1281 	ep = udc_usb_ep->pxa_ep;
1282 	if (!ep || is_ep0(ep))
1283 		return;
1284 
1285 	spin_lock_irqsave(&ep->lock, flags);
1286 
1287 	if (unlikely(!list_empty(&ep->queue)))
1288 		ep_dbg(ep, "called while queue list not empty\n");
1289 	ep_dbg(ep, "called\n");
1290 
1291 	/* for OUT, just read and discard the FIFO contents. */
1292 	if (!ep->dir_in) {
1293 		while (!ep_is_empty(ep))
1294 			udc_ep_readl(ep, UDCDR);
1295 	} else {
1296 		/* most IN status is the same, but ISO can't stall */
1297 		ep_write_UDCCSR(ep,
1298 				UDCCSR_PC | UDCCSR_FEF | UDCCSR_TRN
1299 				| (EPXFERTYPE_is_ISO(ep) ? 0 : UDCCSR_SST));
1300 	}
1301 
1302 	spin_unlock_irqrestore(&ep->lock, flags);
1303 }
1304 
1305 /**
1306  * pxa_ep_enable - Enables usb endpoint
1307  * @_ep: usb endpoint
1308  * @desc: usb endpoint descriptor
1309  *
1310  * Nothing much to do here, as ep configuration is done once and for all
1311  * before udc is enabled. After udc enable, no physical endpoint configuration
1312  * can be changed.
1313  * Function makes sanity checks and flushes the endpoint.
1314  */
1315 static int pxa_ep_enable(struct usb_ep *_ep,
1316 	const struct usb_endpoint_descriptor *desc)
1317 {
1318 	struct pxa_ep		*ep;
1319 	struct udc_usb_ep	*udc_usb_ep;
1320 	struct pxa_udc		*udc;
1321 
1322 	if (!_ep || !desc)
1323 		return -EINVAL;
1324 
1325 	udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
1326 	if (udc_usb_ep->pxa_ep) {
1327 		ep = udc_usb_ep->pxa_ep;
1328 		ep_warn(ep, "usb_ep %s already enabled, doing nothing\n",
1329 			_ep->name);
1330 	} else {
1331 		ep = find_pxa_ep(udc_usb_ep->dev, udc_usb_ep);
1332 	}
1333 
1334 	if (!ep || is_ep0(ep)) {
1335 		dev_err(udc_usb_ep->dev->dev,
1336 			"unable to match pxa_ep for ep %s\n",
1337 			_ep->name);
1338 		return -EINVAL;
1339 	}
1340 
1341 	if ((desc->bDescriptorType != USB_DT_ENDPOINT)
1342 			|| (ep->type != usb_endpoint_type(desc))) {
1343 		ep_err(ep, "type mismatch\n");
1344 		return -EINVAL;
1345 	}
1346 
1347 	if (ep->fifo_size < usb_endpoint_maxp(desc)) {
1348 		ep_err(ep, "bad maxpacket\n");
1349 		return -ERANGE;
1350 	}
1351 
1352 	udc_usb_ep->pxa_ep = ep;
1353 	udc = ep->dev;
1354 
1355 	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
1356 		ep_err(ep, "bogus device state\n");
1357 		return -ESHUTDOWN;
1358 	}
1359 
1360 	ep->enabled = 1;
1361 
1362 	/* flush fifo (mostly for OUT buffers) */
1363 	pxa_ep_fifo_flush(_ep);
1364 
1365 	ep_dbg(ep, "enabled\n");
1366 	return 0;
1367 }
1368 
1369 /**
1370  * pxa_ep_disable - Disable usb endpoint
1371  * @_ep: usb endpoint
1372  *
1373  * Same as for pxa_ep_enable, no physical endpoint configuration can be
1374  * changed.
1375  * Function flushes the endpoint and related requests.
1376  */
1377 static int pxa_ep_disable(struct usb_ep *_ep)
1378 {
1379 	struct pxa_ep		*ep;
1380 	struct udc_usb_ep	*udc_usb_ep;
1381 
1382 	if (!_ep)
1383 		return -EINVAL;
1384 
1385 	udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
1386 	ep = udc_usb_ep->pxa_ep;
1387 	if (!ep || is_ep0(ep) || !list_empty(&ep->queue))
1388 		return -EINVAL;
1389 
1390 	ep->enabled = 0;
1391 	nuke(ep, -ESHUTDOWN);
1392 
1393 	pxa_ep_fifo_flush(_ep);
1394 	udc_usb_ep->pxa_ep = NULL;
1395 
1396 	ep_dbg(ep, "disabled\n");
1397 	return 0;
1398 }
1399 
1400 static const struct usb_ep_ops pxa_ep_ops = {
1401 	.enable		= pxa_ep_enable,
1402 	.disable	= pxa_ep_disable,
1403 
1404 	.alloc_request	= pxa_ep_alloc_request,
1405 	.free_request	= pxa_ep_free_request,
1406 
1407 	.queue		= pxa_ep_queue,
1408 	.dequeue	= pxa_ep_dequeue,
1409 
1410 	.set_halt	= pxa_ep_set_halt,
1411 	.fifo_status	= pxa_ep_fifo_status,
1412 	.fifo_flush	= pxa_ep_fifo_flush,
1413 };
1414 
1415 /**
1416  * dplus_pullup - Connect or disconnect pullup resistor to D+ pin
1417  * @udc: udc device
1418  * @on: 0 if disconnect pullup resistor, 1 otherwise
1419  * Context: any
1420  *
1421  * Handle D+ pullup resistor, make the device visible to the usb bus, and
1422  * declare it as a full speed usb device
1423  */
1424 static void dplus_pullup(struct pxa_udc *udc, int on)
1425 {
1426 	if (udc->gpiod) {
1427 		gpiod_set_value(udc->gpiod, on);
1428 	} else if (udc->udc_command) {
1429 		if (on)
1430 			udc->udc_command(PXA2XX_UDC_CMD_CONNECT);
1431 		else
1432 			udc->udc_command(PXA2XX_UDC_CMD_DISCONNECT);
1433 	}
1434 	udc->pullup_on = on;
1435 }
1436 
1437 /**
1438  * pxa_udc_get_frame - Returns usb frame number
1439  * @_gadget: usb gadget
1440  */
1441 static int pxa_udc_get_frame(struct usb_gadget *_gadget)
1442 {
1443 	struct pxa_udc *udc = to_gadget_udc(_gadget);
1444 
1445 	return (udc_readl(udc, UDCFNR) & 0x7ff);
1446 }
1447 
1448 /**
1449  * pxa_udc_wakeup - Force udc device out of suspend
1450  * @_gadget: usb gadget
1451  *
1452  * Returns 0 if successful, error code otherwise
1453  */
1454 static int pxa_udc_wakeup(struct usb_gadget *_gadget)
1455 {
1456 	struct pxa_udc *udc = to_gadget_udc(_gadget);
1457 
1458 	/* host may not have enabled remote wakeup */
1459 	if ((udc_readl(udc, UDCCR) & UDCCR_DWRE) == 0)
1460 		return -EHOSTUNREACH;
1461 	udc_set_mask_UDCCR(udc, UDCCR_UDR);
1462 	return 0;
1463 }
1464 
1465 static void udc_enable(struct pxa_udc *udc);
1466 static void udc_disable(struct pxa_udc *udc);
1467 
1468 /**
1469  * should_enable_udc - Tells if UDC should be enabled
1470  * @udc: udc device
1471  * Context: any
1472  *
1473  * The UDC should be enabled if :
1474  *  - the pullup resistor is connected
1475  *  - and a gadget driver is bound
1476  *  - and vbus is sensed (or no vbus sense is available)
1477  *
1478  * Returns 1 if UDC should be enabled, 0 otherwise
1479  */
1480 static int should_enable_udc(struct pxa_udc *udc)
1481 {
1482 	int put_on;
1483 
1484 	put_on = ((udc->pullup_on) && (udc->driver));
1485 	put_on &= ((udc->vbus_sensed) || (IS_ERR_OR_NULL(udc->transceiver)));
1486 	return put_on;
1487 }
1488 
1489 /**
1490  * should_disable_udc - Tells if UDC should be disabled
1491  * @udc: udc device
1492  * Context: any
1493  *
1494  * The UDC should be disabled if :
1495  *  - the pullup resistor is not connected
1496  *  - or no gadget driver is bound
1497  *  - or no vbus is sensed (when vbus sesing is available)
1498  *
1499  * Returns 1 if UDC should be disabled
1500  */
1501 static int should_disable_udc(struct pxa_udc *udc)
1502 {
1503 	int put_off;
1504 
1505 	put_off = ((!udc->pullup_on) || (!udc->driver));
1506 	put_off |= ((!udc->vbus_sensed) && (!IS_ERR_OR_NULL(udc->transceiver)));
1507 	return put_off;
1508 }
1509 
1510 /**
1511  * pxa_udc_pullup - Offer manual D+ pullup control
1512  * @_gadget: usb gadget using the control
1513  * @is_active: 0 if disconnect, else connect D+ pullup resistor
1514  *
1515  * Context: task context, might sleep
1516  *
1517  * Returns 0 if OK, -EOPNOTSUPP if udc driver doesn't handle D+ pullup
1518  */
1519 static int pxa_udc_pullup(struct usb_gadget *_gadget, int is_active)
1520 {
1521 	struct pxa_udc *udc = to_gadget_udc(_gadget);
1522 
1523 	if (!udc->gpiod && !udc->udc_command)
1524 		return -EOPNOTSUPP;
1525 
1526 	dplus_pullup(udc, is_active);
1527 
1528 	if (should_enable_udc(udc))
1529 		udc_enable(udc);
1530 	if (should_disable_udc(udc))
1531 		udc_disable(udc);
1532 	return 0;
1533 }
1534 
1535 /**
1536  * pxa_udc_vbus_session - Called by external transceiver to enable/disable udc
1537  * @_gadget: usb gadget
1538  * @is_active: 0 if should disable the udc, 1 if should enable
1539  *
1540  * Enables the udc, and optionnaly activates D+ pullup resistor. Or disables the
1541  * udc, and deactivates D+ pullup resistor.
1542  *
1543  * Returns 0
1544  */
1545 static int pxa_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
1546 {
1547 	struct pxa_udc *udc = to_gadget_udc(_gadget);
1548 
1549 	udc->vbus_sensed = is_active;
1550 	if (should_enable_udc(udc))
1551 		udc_enable(udc);
1552 	if (should_disable_udc(udc))
1553 		udc_disable(udc);
1554 
1555 	return 0;
1556 }
1557 
1558 /**
1559  * pxa_udc_vbus_draw - Called by gadget driver after SET_CONFIGURATION completed
1560  * @_gadget: usb gadget
1561  * @mA: current drawn
1562  *
1563  * Context: task context, might sleep
1564  *
1565  * Called after a configuration was chosen by a USB host, to inform how much
1566  * current can be drawn by the device from VBus line.
1567  *
1568  * Returns 0 or -EOPNOTSUPP if no transceiver is handling the udc
1569  */
1570 static int pxa_udc_vbus_draw(struct usb_gadget *_gadget, unsigned mA)
1571 {
1572 	struct pxa_udc *udc;
1573 
1574 	udc = to_gadget_udc(_gadget);
1575 	if (!IS_ERR_OR_NULL(udc->transceiver))
1576 		return usb_phy_set_power(udc->transceiver, mA);
1577 	return -EOPNOTSUPP;
1578 }
1579 
1580 /**
1581  * pxa_udc_phy_event - Called by phy upon VBus event
1582  * @nb: notifier block
1583  * @action: phy action, is vbus connect or disconnect
1584  * @data: the usb_gadget structure in pxa_udc
1585  *
1586  * Called by the USB Phy when a cable connect or disconnect is sensed.
1587  *
1588  * Returns 0
1589  */
1590 static int pxa_udc_phy_event(struct notifier_block *nb, unsigned long action,
1591 			     void *data)
1592 {
1593 	struct usb_gadget *gadget = data;
1594 
1595 	switch (action) {
1596 	case USB_EVENT_VBUS:
1597 		usb_gadget_vbus_connect(gadget);
1598 		return NOTIFY_OK;
1599 	case USB_EVENT_NONE:
1600 		usb_gadget_vbus_disconnect(gadget);
1601 		return NOTIFY_OK;
1602 	default:
1603 		return NOTIFY_DONE;
1604 	}
1605 }
1606 
1607 static struct notifier_block pxa27x_udc_phy = {
1608 	.notifier_call = pxa_udc_phy_event,
1609 };
1610 
1611 static int pxa27x_udc_start(struct usb_gadget *g,
1612 		struct usb_gadget_driver *driver);
1613 static int pxa27x_udc_stop(struct usb_gadget *g);
1614 
1615 static const struct usb_gadget_ops pxa_udc_ops = {
1616 	.get_frame	= pxa_udc_get_frame,
1617 	.wakeup		= pxa_udc_wakeup,
1618 	.pullup		= pxa_udc_pullup,
1619 	.vbus_session	= pxa_udc_vbus_session,
1620 	.vbus_draw	= pxa_udc_vbus_draw,
1621 	.udc_start	= pxa27x_udc_start,
1622 	.udc_stop	= pxa27x_udc_stop,
1623 };
1624 
1625 /**
1626  * udc_disable - disable udc device controller
1627  * @udc: udc device
1628  * Context: any
1629  *
1630  * Disables the udc device : disables clocks, udc interrupts, control endpoint
1631  * interrupts.
1632  */
1633 static void udc_disable(struct pxa_udc *udc)
1634 {
1635 	if (!udc->enabled)
1636 		return;
1637 
1638 	udc_writel(udc, UDCICR0, 0);
1639 	udc_writel(udc, UDCICR1, 0);
1640 
1641 	udc_clear_mask_UDCCR(udc, UDCCR_UDE);
1642 
1643 	ep0_idle(udc);
1644 	udc->gadget.speed = USB_SPEED_UNKNOWN;
1645 	clk_disable(udc->clk);
1646 
1647 	udc->enabled = 0;
1648 }
1649 
1650 /**
1651  * udc_init_data - Initialize udc device data structures
1652  * @dev: udc device
1653  *
1654  * Initializes gadget endpoint list, endpoints locks. No action is taken
1655  * on the hardware.
1656  */
1657 static void udc_init_data(struct pxa_udc *dev)
1658 {
1659 	int i;
1660 	struct pxa_ep *ep;
1661 
1662 	/* device/ep0 records init */
1663 	INIT_LIST_HEAD(&dev->gadget.ep_list);
1664 	INIT_LIST_HEAD(&dev->gadget.ep0->ep_list);
1665 	dev->udc_usb_ep[0].pxa_ep = &dev->pxa_ep[0];
1666 	dev->gadget.quirk_altset_not_supp = 1;
1667 	ep0_idle(dev);
1668 
1669 	/* PXA endpoints init */
1670 	for (i = 0; i < NR_PXA_ENDPOINTS; i++) {
1671 		ep = &dev->pxa_ep[i];
1672 
1673 		ep->enabled = is_ep0(ep);
1674 		INIT_LIST_HEAD(&ep->queue);
1675 		spin_lock_init(&ep->lock);
1676 	}
1677 
1678 	/* USB endpoints init */
1679 	for (i = 1; i < NR_USB_ENDPOINTS; i++) {
1680 		list_add_tail(&dev->udc_usb_ep[i].usb_ep.ep_list,
1681 				&dev->gadget.ep_list);
1682 		usb_ep_set_maxpacket_limit(&dev->udc_usb_ep[i].usb_ep,
1683 					   dev->udc_usb_ep[i].usb_ep.maxpacket);
1684 	}
1685 }
1686 
1687 /**
1688  * udc_enable - Enables the udc device
1689  * @udc: udc device
1690  *
1691  * Enables the udc device : enables clocks, udc interrupts, control endpoint
1692  * interrupts, sets usb as UDC client and setups endpoints.
1693  */
1694 static void udc_enable(struct pxa_udc *udc)
1695 {
1696 	if (udc->enabled)
1697 		return;
1698 
1699 	clk_enable(udc->clk);
1700 	udc_writel(udc, UDCICR0, 0);
1701 	udc_writel(udc, UDCICR1, 0);
1702 	udc_clear_mask_UDCCR(udc, UDCCR_UDE);
1703 
1704 	ep0_idle(udc);
1705 	udc->gadget.speed = USB_SPEED_FULL;
1706 	memset(&udc->stats, 0, sizeof(udc->stats));
1707 
1708 	pxa_eps_setup(udc);
1709 	udc_set_mask_UDCCR(udc, UDCCR_UDE);
1710 	ep_write_UDCCSR(&udc->pxa_ep[0], UDCCSR0_ACM);
1711 	udelay(2);
1712 	if (udc_readl(udc, UDCCR) & UDCCR_EMCE)
1713 		dev_err(udc->dev, "Configuration errors, udc disabled\n");
1714 
1715 	/*
1716 	 * Caller must be able to sleep in order to cope with startup transients
1717 	 */
1718 	msleep(100);
1719 
1720 	/* enable suspend/resume and reset irqs */
1721 	udc_writel(udc, UDCICR1,
1722 			UDCICR1_IECC | UDCICR1_IERU
1723 			| UDCICR1_IESU | UDCICR1_IERS);
1724 
1725 	/* enable ep0 irqs */
1726 	pio_irq_enable(&udc->pxa_ep[0]);
1727 
1728 	udc->enabled = 1;
1729 }
1730 
1731 /**
1732  * pxa27x_udc_start - Register gadget driver
1733  * @g: gadget
1734  * @driver: gadget driver
1735  *
1736  * When a driver is successfully registered, it will receive control requests
1737  * including set_configuration(), which enables non-control requests.  Then
1738  * usb traffic follows until a disconnect is reported.  Then a host may connect
1739  * again, or the driver might get unbound.
1740  *
1741  * Note that the udc is not automatically enabled. Check function
1742  * should_enable_udc().
1743  *
1744  * Returns 0 if no error, -EINVAL, -ENODEV, -EBUSY otherwise
1745  */
1746 static int pxa27x_udc_start(struct usb_gadget *g,
1747 		struct usb_gadget_driver *driver)
1748 {
1749 	struct pxa_udc *udc = to_pxa(g);
1750 	int retval;
1751 
1752 	/* first hook up the driver ... */
1753 	udc->driver = driver;
1754 
1755 	if (!IS_ERR_OR_NULL(udc->transceiver)) {
1756 		retval = otg_set_peripheral(udc->transceiver->otg,
1757 						&udc->gadget);
1758 		if (retval) {
1759 			dev_err(udc->dev, "can't bind to transceiver\n");
1760 			goto fail;
1761 		}
1762 	}
1763 
1764 	if (should_enable_udc(udc))
1765 		udc_enable(udc);
1766 	return 0;
1767 
1768 fail:
1769 	udc->driver = NULL;
1770 	return retval;
1771 }
1772 
1773 /**
1774  * stop_activity - Stops udc endpoints
1775  * @udc: udc device
1776  *
1777  * Disables all udc endpoints (even control endpoint), report disconnect to
1778  * the gadget user.
1779  */
1780 static void stop_activity(struct pxa_udc *udc)
1781 {
1782 	int i;
1783 
1784 	udc->gadget.speed = USB_SPEED_UNKNOWN;
1785 
1786 	for (i = 0; i < NR_USB_ENDPOINTS; i++)
1787 		pxa_ep_disable(&udc->udc_usb_ep[i].usb_ep);
1788 }
1789 
1790 /**
1791  * pxa27x_udc_stop - Unregister the gadget driver
1792  * @g: gadget
1793  *
1794  * Returns 0 if no error, -ENODEV, -EINVAL otherwise
1795  */
1796 static int pxa27x_udc_stop(struct usb_gadget *g)
1797 {
1798 	struct pxa_udc *udc = to_pxa(g);
1799 
1800 	stop_activity(udc);
1801 	udc_disable(udc);
1802 
1803 	udc->driver = NULL;
1804 
1805 	if (!IS_ERR_OR_NULL(udc->transceiver))
1806 		return otg_set_peripheral(udc->transceiver->otg, NULL);
1807 	return 0;
1808 }
1809 
1810 /**
1811  * handle_ep0_ctrl_req - handle control endpoint control request
1812  * @udc: udc device
1813  * @req: control request
1814  */
1815 static void handle_ep0_ctrl_req(struct pxa_udc *udc,
1816 				struct pxa27x_request *req)
1817 {
1818 	struct pxa_ep *ep = &udc->pxa_ep[0];
1819 	union {
1820 		struct usb_ctrlrequest	r;
1821 		u32			word[2];
1822 	} u;
1823 	int i;
1824 	int have_extrabytes = 0;
1825 	unsigned long flags;
1826 
1827 	nuke(ep, -EPROTO);
1828 	spin_lock_irqsave(&ep->lock, flags);
1829 
1830 	/*
1831 	 * In the PXA320 manual, in the section about Back-to-Back setup
1832 	 * packets, it describes this situation.  The solution is to set OPC to
1833 	 * get rid of the status packet, and then continue with the setup
1834 	 * packet. Generalize to pxa27x CPUs.
1835 	 */
1836 	if (epout_has_pkt(ep) && (ep_count_bytes_remain(ep) == 0))
1837 		ep_write_UDCCSR(ep, UDCCSR0_OPC);
1838 
1839 	/* read SETUP packet */
1840 	for (i = 0; i < 2; i++) {
1841 		if (unlikely(ep_is_empty(ep)))
1842 			goto stall;
1843 		u.word[i] = udc_ep_readl(ep, UDCDR);
1844 	}
1845 
1846 	have_extrabytes = !ep_is_empty(ep);
1847 	while (!ep_is_empty(ep)) {
1848 		i = udc_ep_readl(ep, UDCDR);
1849 		ep_err(ep, "wrong to have extra bytes for setup : 0x%08x\n", i);
1850 	}
1851 
1852 	ep_dbg(ep, "SETUP %02x.%02x v%04x i%04x l%04x\n",
1853 		u.r.bRequestType, u.r.bRequest,
1854 		le16_to_cpu(u.r.wValue), le16_to_cpu(u.r.wIndex),
1855 		le16_to_cpu(u.r.wLength));
1856 	if (unlikely(have_extrabytes))
1857 		goto stall;
1858 
1859 	if (u.r.bRequestType & USB_DIR_IN)
1860 		set_ep0state(udc, IN_DATA_STAGE);
1861 	else
1862 		set_ep0state(udc, OUT_DATA_STAGE);
1863 
1864 	/* Tell UDC to enter Data Stage */
1865 	ep_write_UDCCSR(ep, UDCCSR0_SA | UDCCSR0_OPC);
1866 
1867 	spin_unlock_irqrestore(&ep->lock, flags);
1868 	i = udc->driver->setup(&udc->gadget, &u.r);
1869 	spin_lock_irqsave(&ep->lock, flags);
1870 	if (i < 0)
1871 		goto stall;
1872 out:
1873 	spin_unlock_irqrestore(&ep->lock, flags);
1874 	return;
1875 stall:
1876 	ep_dbg(ep, "protocol STALL, udccsr0=%03x err %d\n",
1877 		udc_ep_readl(ep, UDCCSR), i);
1878 	ep_write_UDCCSR(ep, UDCCSR0_FST | UDCCSR0_FTF);
1879 	set_ep0state(udc, STALL);
1880 	goto out;
1881 }
1882 
1883 /**
1884  * handle_ep0 - Handle control endpoint data transfers
1885  * @udc: udc device
1886  * @fifo_irq: 1 if triggered by fifo service type irq
1887  * @opc_irq: 1 if triggered by output packet complete type irq
1888  *
1889  * Context : interrupt handler
1890  *
1891  * Tries to transfer all pending request data into the endpoint and/or
1892  * transfer all pending data in the endpoint into usb requests.
1893  * Handles states of ep0 automata.
1894  *
1895  * PXA27x hardware handles several standard usb control requests without
1896  * driver notification.  The requests fully handled by hardware are :
1897  *  SET_ADDRESS, SET_FEATURE, CLEAR_FEATURE, GET_CONFIGURATION, GET_INTERFACE,
1898  *  GET_STATUS
1899  * The requests handled by hardware, but with irq notification are :
1900  *  SYNCH_FRAME, SET_CONFIGURATION, SET_INTERFACE
1901  * The remaining standard requests really handled by handle_ep0 are :
1902  *  GET_DESCRIPTOR, SET_DESCRIPTOR, specific requests.
1903  * Requests standardized outside of USB 2.0 chapter 9 are handled more
1904  * uniformly, by gadget drivers.
1905  *
1906  * The control endpoint state machine is _not_ USB spec compliant, it's even
1907  * hardly compliant with Intel PXA270 developers guide.
1908  * The key points which inferred this state machine are :
1909  *   - on every setup token, bit UDCCSR0_SA is raised and held until cleared by
1910  *     software.
1911  *   - on every OUT packet received, UDCCSR0_OPC is raised and held until
1912  *     cleared by software.
1913  *   - clearing UDCCSR0_OPC always flushes ep0. If in setup stage, never do it
1914  *     before reading ep0.
1915  *     This is true only for PXA27x. This is not true anymore for PXA3xx family
1916  *     (check Back-to-Back setup packet in developers guide).
1917  *   - irq can be called on a "packet complete" event (opc_irq=1), while
1918  *     UDCCSR0_OPC is not yet raised (delta can be as big as 100ms
1919  *     from experimentation).
1920  *   - as UDCCSR0_SA can be activated while in irq handling, and clearing
1921  *     UDCCSR0_OPC would flush the setup data, we almost never clear UDCCSR0_OPC
1922  *     => we never actually read the "status stage" packet of an IN data stage
1923  *     => this is not documented in Intel documentation
1924  *   - hardware as no idea of STATUS STAGE, it only handle SETUP STAGE and DATA
1925  *     STAGE. The driver add STATUS STAGE to send last zero length packet in
1926  *     OUT_STATUS_STAGE.
1927  *   - special attention was needed for IN_STATUS_STAGE. If a packet complete
1928  *     event is detected, we terminate the status stage without ackowledging the
1929  *     packet (not to risk to loose a potential SETUP packet)
1930  */
1931 static void handle_ep0(struct pxa_udc *udc, int fifo_irq, int opc_irq)
1932 {
1933 	u32			udccsr0;
1934 	struct pxa_ep		*ep = &udc->pxa_ep[0];
1935 	struct pxa27x_request	*req = NULL;
1936 	int			completed = 0;
1937 
1938 	if (!list_empty(&ep->queue))
1939 		req = list_entry(ep->queue.next, struct pxa27x_request, queue);
1940 
1941 	udccsr0 = udc_ep_readl(ep, UDCCSR);
1942 	ep_dbg(ep, "state=%s, req=%p, udccsr0=0x%03x, udcbcr=%d, irq_msk=%x\n",
1943 		EP0_STNAME(udc), req, udccsr0, udc_ep_readl(ep, UDCBCR),
1944 		(fifo_irq << 1 | opc_irq));
1945 
1946 	if (udccsr0 & UDCCSR0_SST) {
1947 		ep_dbg(ep, "clearing stall status\n");
1948 		nuke(ep, -EPIPE);
1949 		ep_write_UDCCSR(ep, UDCCSR0_SST);
1950 		ep0_idle(udc);
1951 	}
1952 
1953 	if (udccsr0 & UDCCSR0_SA) {
1954 		nuke(ep, 0);
1955 		set_ep0state(udc, SETUP_STAGE);
1956 	}
1957 
1958 	switch (udc->ep0state) {
1959 	case WAIT_FOR_SETUP:
1960 		/*
1961 		 * Hardware bug : beware, we cannot clear OPC, since we would
1962 		 * miss a potential OPC irq for a setup packet.
1963 		 * So, we only do ... nothing, and hope for a next irq with
1964 		 * UDCCSR0_SA set.
1965 		 */
1966 		break;
1967 	case SETUP_STAGE:
1968 		udccsr0 &= UDCCSR0_CTRL_REQ_MASK;
1969 		if (likely(udccsr0 == UDCCSR0_CTRL_REQ_MASK))
1970 			handle_ep0_ctrl_req(udc, req);
1971 		break;
1972 	case IN_DATA_STAGE:			/* GET_DESCRIPTOR */
1973 		if (epout_has_pkt(ep))
1974 			ep_write_UDCCSR(ep, UDCCSR0_OPC);
1975 		if (req && !ep_is_full(ep))
1976 			completed = write_ep0_fifo(ep, req);
1977 		if (completed)
1978 			ep0_end_in_req(ep, req, NULL);
1979 		break;
1980 	case OUT_DATA_STAGE:			/* SET_DESCRIPTOR */
1981 		if (epout_has_pkt(ep) && req)
1982 			completed = read_ep0_fifo(ep, req);
1983 		if (completed)
1984 			ep0_end_out_req(ep, req, NULL);
1985 		break;
1986 	case STALL:
1987 		ep_write_UDCCSR(ep, UDCCSR0_FST);
1988 		break;
1989 	case IN_STATUS_STAGE:
1990 		/*
1991 		 * Hardware bug : beware, we cannot clear OPC, since we would
1992 		 * miss a potential PC irq for a setup packet.
1993 		 * So, we only put the ep0 into WAIT_FOR_SETUP state.
1994 		 */
1995 		if (opc_irq)
1996 			ep0_idle(udc);
1997 		break;
1998 	case OUT_STATUS_STAGE:
1999 	case WAIT_ACK_SET_CONF_INTERF:
2000 		ep_warn(ep, "should never get in %s state here!!!\n",
2001 				EP0_STNAME(ep->dev));
2002 		ep0_idle(udc);
2003 		break;
2004 	}
2005 }
2006 
2007 /**
2008  * handle_ep - Handle endpoint data tranfers
2009  * @ep: pxa physical endpoint
2010  *
2011  * Tries to transfer all pending request data into the endpoint and/or
2012  * transfer all pending data in the endpoint into usb requests.
2013  *
2014  * Is always called from the interrupt handler. ep->lock must not be held.
2015  */
2016 static void handle_ep(struct pxa_ep *ep)
2017 {
2018 	struct pxa27x_request	*req;
2019 	int completed;
2020 	u32 udccsr;
2021 	int is_in = ep->dir_in;
2022 	int loop = 0;
2023 	unsigned long		flags;
2024 
2025 	spin_lock_irqsave(&ep->lock, flags);
2026 	if (ep->in_handle_ep)
2027 		goto recursion_detected;
2028 	ep->in_handle_ep = 1;
2029 
2030 	do {
2031 		completed = 0;
2032 		udccsr = udc_ep_readl(ep, UDCCSR);
2033 
2034 		if (likely(!list_empty(&ep->queue)))
2035 			req = list_entry(ep->queue.next,
2036 					struct pxa27x_request, queue);
2037 		else
2038 			req = NULL;
2039 
2040 		ep_dbg(ep, "req:%p, udccsr 0x%03x loop=%d\n",
2041 				req, udccsr, loop++);
2042 
2043 		if (unlikely(udccsr & (UDCCSR_SST | UDCCSR_TRN)))
2044 			udc_ep_writel(ep, UDCCSR,
2045 					udccsr & (UDCCSR_SST | UDCCSR_TRN));
2046 		if (!req)
2047 			break;
2048 
2049 		if (unlikely(is_in)) {
2050 			if (likely(!ep_is_full(ep)))
2051 				completed = write_fifo(ep, req);
2052 		} else {
2053 			if (likely(epout_has_pkt(ep)))
2054 				completed = read_fifo(ep, req);
2055 		}
2056 
2057 		if (completed) {
2058 			if (is_in)
2059 				ep_end_in_req(ep, req, &flags);
2060 			else
2061 				ep_end_out_req(ep, req, &flags);
2062 		}
2063 	} while (completed);
2064 
2065 	ep->in_handle_ep = 0;
2066 recursion_detected:
2067 	spin_unlock_irqrestore(&ep->lock, flags);
2068 }
2069 
2070 /**
2071  * pxa27x_change_configuration - Handle SET_CONF usb request notification
2072  * @udc: udc device
2073  * @config: usb configuration
2074  *
2075  * Post the request to upper level.
2076  * Don't use any pxa specific harware configuration capabilities
2077  */
2078 static void pxa27x_change_configuration(struct pxa_udc *udc, int config)
2079 {
2080 	struct usb_ctrlrequest req ;
2081 
2082 	dev_dbg(udc->dev, "config=%d\n", config);
2083 
2084 	udc->config = config;
2085 	udc->last_interface = 0;
2086 	udc->last_alternate = 0;
2087 
2088 	req.bRequestType = 0;
2089 	req.bRequest = USB_REQ_SET_CONFIGURATION;
2090 	req.wValue = config;
2091 	req.wIndex = 0;
2092 	req.wLength = 0;
2093 
2094 	set_ep0state(udc, WAIT_ACK_SET_CONF_INTERF);
2095 	udc->driver->setup(&udc->gadget, &req);
2096 	ep_write_UDCCSR(&udc->pxa_ep[0], UDCCSR0_AREN);
2097 }
2098 
2099 /**
2100  * pxa27x_change_interface - Handle SET_INTERF usb request notification
2101  * @udc: udc device
2102  * @iface: interface number
2103  * @alt: alternate setting number
2104  *
2105  * Post the request to upper level.
2106  * Don't use any pxa specific harware configuration capabilities
2107  */
2108 static void pxa27x_change_interface(struct pxa_udc *udc, int iface, int alt)
2109 {
2110 	struct usb_ctrlrequest  req;
2111 
2112 	dev_dbg(udc->dev, "interface=%d, alternate setting=%d\n", iface, alt);
2113 
2114 	udc->last_interface = iface;
2115 	udc->last_alternate = alt;
2116 
2117 	req.bRequestType = USB_RECIP_INTERFACE;
2118 	req.bRequest = USB_REQ_SET_INTERFACE;
2119 	req.wValue = alt;
2120 	req.wIndex = iface;
2121 	req.wLength = 0;
2122 
2123 	set_ep0state(udc, WAIT_ACK_SET_CONF_INTERF);
2124 	udc->driver->setup(&udc->gadget, &req);
2125 	ep_write_UDCCSR(&udc->pxa_ep[0], UDCCSR0_AREN);
2126 }
2127 
2128 /*
2129  * irq_handle_data - Handle data transfer
2130  * @irq: irq IRQ number
2131  * @udc: dev pxa_udc device structure
2132  *
2133  * Called from irq handler, transferts data to or from endpoint to queue
2134  */
2135 static void irq_handle_data(int irq, struct pxa_udc *udc)
2136 {
2137 	int i;
2138 	struct pxa_ep *ep;
2139 	u32 udcisr0 = udc_readl(udc, UDCISR0) & UDCCISR0_EP_MASK;
2140 	u32 udcisr1 = udc_readl(udc, UDCISR1) & UDCCISR1_EP_MASK;
2141 
2142 	if (udcisr0 & UDCISR_INT_MASK) {
2143 		udc->pxa_ep[0].stats.irqs++;
2144 		udc_writel(udc, UDCISR0, UDCISR_INT(0, UDCISR_INT_MASK));
2145 		handle_ep0(udc, !!(udcisr0 & UDCICR_FIFOERR),
2146 				!!(udcisr0 & UDCICR_PKTCOMPL));
2147 	}
2148 
2149 	udcisr0 >>= 2;
2150 	for (i = 1; udcisr0 != 0 && i < 16; udcisr0 >>= 2, i++) {
2151 		if (!(udcisr0 & UDCISR_INT_MASK))
2152 			continue;
2153 
2154 		udc_writel(udc, UDCISR0, UDCISR_INT(i, UDCISR_INT_MASK));
2155 
2156 		WARN_ON(i >= ARRAY_SIZE(udc->pxa_ep));
2157 		if (i < ARRAY_SIZE(udc->pxa_ep)) {
2158 			ep = &udc->pxa_ep[i];
2159 			ep->stats.irqs++;
2160 			handle_ep(ep);
2161 		}
2162 	}
2163 
2164 	for (i = 16; udcisr1 != 0 && i < 24; udcisr1 >>= 2, i++) {
2165 		udc_writel(udc, UDCISR1, UDCISR_INT(i - 16, UDCISR_INT_MASK));
2166 		if (!(udcisr1 & UDCISR_INT_MASK))
2167 			continue;
2168 
2169 		WARN_ON(i >= ARRAY_SIZE(udc->pxa_ep));
2170 		if (i < ARRAY_SIZE(udc->pxa_ep)) {
2171 			ep = &udc->pxa_ep[i];
2172 			ep->stats.irqs++;
2173 			handle_ep(ep);
2174 		}
2175 	}
2176 
2177 }
2178 
2179 /**
2180  * irq_udc_suspend - Handle IRQ "UDC Suspend"
2181  * @udc: udc device
2182  */
2183 static void irq_udc_suspend(struct pxa_udc *udc)
2184 {
2185 	udc_writel(udc, UDCISR1, UDCISR1_IRSU);
2186 	udc->stats.irqs_suspend++;
2187 
2188 	if (udc->gadget.speed != USB_SPEED_UNKNOWN
2189 			&& udc->driver && udc->driver->suspend)
2190 		udc->driver->suspend(&udc->gadget);
2191 	ep0_idle(udc);
2192 }
2193 
2194 /**
2195   * irq_udc_resume - Handle IRQ "UDC Resume"
2196   * @udc: udc device
2197   */
2198 static void irq_udc_resume(struct pxa_udc *udc)
2199 {
2200 	udc_writel(udc, UDCISR1, UDCISR1_IRRU);
2201 	udc->stats.irqs_resume++;
2202 
2203 	if (udc->gadget.speed != USB_SPEED_UNKNOWN
2204 			&& udc->driver && udc->driver->resume)
2205 		udc->driver->resume(&udc->gadget);
2206 }
2207 
2208 /**
2209  * irq_udc_reconfig - Handle IRQ "UDC Change Configuration"
2210  * @udc: udc device
2211  */
2212 static void irq_udc_reconfig(struct pxa_udc *udc)
2213 {
2214 	unsigned config, interface, alternate, config_change;
2215 	u32 udccr = udc_readl(udc, UDCCR);
2216 
2217 	udc_writel(udc, UDCISR1, UDCISR1_IRCC);
2218 	udc->stats.irqs_reconfig++;
2219 
2220 	config = (udccr & UDCCR_ACN) >> UDCCR_ACN_S;
2221 	config_change = (config != udc->config);
2222 	pxa27x_change_configuration(udc, config);
2223 
2224 	interface = (udccr & UDCCR_AIN) >> UDCCR_AIN_S;
2225 	alternate = (udccr & UDCCR_AAISN) >> UDCCR_AAISN_S;
2226 	pxa27x_change_interface(udc, interface, alternate);
2227 
2228 	if (config_change)
2229 		update_pxa_ep_matches(udc);
2230 	udc_set_mask_UDCCR(udc, UDCCR_SMAC);
2231 }
2232 
2233 /**
2234  * irq_udc_reset - Handle IRQ "UDC Reset"
2235  * @udc: udc device
2236  */
2237 static void irq_udc_reset(struct pxa_udc *udc)
2238 {
2239 	u32 udccr = udc_readl(udc, UDCCR);
2240 	struct pxa_ep *ep = &udc->pxa_ep[0];
2241 
2242 	dev_info(udc->dev, "USB reset\n");
2243 	udc_writel(udc, UDCISR1, UDCISR1_IRRS);
2244 	udc->stats.irqs_reset++;
2245 
2246 	if ((udccr & UDCCR_UDA) == 0) {
2247 		dev_dbg(udc->dev, "USB reset start\n");
2248 		stop_activity(udc);
2249 	}
2250 	udc->gadget.speed = USB_SPEED_FULL;
2251 	memset(&udc->stats, 0, sizeof udc->stats);
2252 
2253 	nuke(ep, -EPROTO);
2254 	ep_write_UDCCSR(ep, UDCCSR0_FTF | UDCCSR0_OPC);
2255 	ep0_idle(udc);
2256 }
2257 
2258 /**
2259  * pxa_udc_irq - Main irq handler
2260  * @irq: irq number
2261  * @_dev: udc device
2262  *
2263  * Handles all udc interrupts
2264  */
2265 static irqreturn_t pxa_udc_irq(int irq, void *_dev)
2266 {
2267 	struct pxa_udc *udc = _dev;
2268 	u32 udcisr0 = udc_readl(udc, UDCISR0);
2269 	u32 udcisr1 = udc_readl(udc, UDCISR1);
2270 	u32 udccr = udc_readl(udc, UDCCR);
2271 	u32 udcisr1_spec;
2272 
2273 	dev_vdbg(udc->dev, "Interrupt, UDCISR0:0x%08x, UDCISR1:0x%08x, "
2274 		 "UDCCR:0x%08x\n", udcisr0, udcisr1, udccr);
2275 
2276 	udcisr1_spec = udcisr1 & 0xf8000000;
2277 	if (unlikely(udcisr1_spec & UDCISR1_IRSU))
2278 		irq_udc_suspend(udc);
2279 	if (unlikely(udcisr1_spec & UDCISR1_IRRU))
2280 		irq_udc_resume(udc);
2281 	if (unlikely(udcisr1_spec & UDCISR1_IRCC))
2282 		irq_udc_reconfig(udc);
2283 	if (unlikely(udcisr1_spec & UDCISR1_IRRS))
2284 		irq_udc_reset(udc);
2285 
2286 	if ((udcisr0 & UDCCISR0_EP_MASK) | (udcisr1 & UDCCISR1_EP_MASK))
2287 		irq_handle_data(irq, udc);
2288 
2289 	return IRQ_HANDLED;
2290 }
2291 
2292 static struct pxa_udc memory = {
2293 	.gadget = {
2294 		.ops		= &pxa_udc_ops,
2295 		.ep0		= &memory.udc_usb_ep[0].usb_ep,
2296 		.name		= driver_name,
2297 		.dev = {
2298 			.init_name	= "gadget",
2299 		},
2300 	},
2301 
2302 	.udc_usb_ep = {
2303 		USB_EP_CTRL,
2304 		USB_EP_OUT_BULK(1),
2305 		USB_EP_IN_BULK(2),
2306 		USB_EP_IN_ISO(3),
2307 		USB_EP_OUT_ISO(4),
2308 		USB_EP_IN_INT(5),
2309 	},
2310 
2311 	.pxa_ep = {
2312 		PXA_EP_CTRL,
2313 		/* Endpoints for gadget zero */
2314 		PXA_EP_OUT_BULK(1, 1, 3, 0, 0),
2315 		PXA_EP_IN_BULK(2,  2, 3, 0, 0),
2316 		/* Endpoints for ether gadget, file storage gadget */
2317 		PXA_EP_OUT_BULK(3, 1, 1, 0, 0),
2318 		PXA_EP_IN_BULK(4,  2, 1, 0, 0),
2319 		PXA_EP_IN_ISO(5,   3, 1, 0, 0),
2320 		PXA_EP_OUT_ISO(6,  4, 1, 0, 0),
2321 		PXA_EP_IN_INT(7,   5, 1, 0, 0),
2322 		/* Endpoints for RNDIS, serial */
2323 		PXA_EP_OUT_BULK(8, 1, 2, 0, 0),
2324 		PXA_EP_IN_BULK(9,  2, 2, 0, 0),
2325 		PXA_EP_IN_INT(10,  5, 2, 0, 0),
2326 		/*
2327 		 * All the following endpoints are only for completion.  They
2328 		 * won't never work, as multiple interfaces are really broken on
2329 		 * the pxa.
2330 		*/
2331 		PXA_EP_OUT_BULK(11, 1, 2, 1, 0),
2332 		PXA_EP_IN_BULK(12,  2, 2, 1, 0),
2333 		/* Endpoint for CDC Ether */
2334 		PXA_EP_OUT_BULK(13, 1, 1, 1, 1),
2335 		PXA_EP_IN_BULK(14,  2, 1, 1, 1),
2336 	}
2337 };
2338 
2339 #if defined(CONFIG_OF)
2340 static const struct of_device_id udc_pxa_dt_ids[] = {
2341 	{ .compatible = "marvell,pxa270-udc" },
2342 	{}
2343 };
2344 MODULE_DEVICE_TABLE(of, udc_pxa_dt_ids);
2345 #endif
2346 
2347 /**
2348  * pxa_udc_probe - probes the udc device
2349  * @pdev: platform device
2350  *
2351  * Perform basic init : allocates udc clock, creates sysfs files, requests
2352  * irq.
2353  */
2354 static int pxa_udc_probe(struct platform_device *pdev)
2355 {
2356 	struct pxa_udc *udc = &memory;
2357 	int retval = 0, gpio;
2358 	struct pxa2xx_udc_mach_info *mach = dev_get_platdata(&pdev->dev);
2359 	unsigned long gpio_flags;
2360 
2361 	if (mach) {
2362 		gpio_flags = mach->gpio_pullup_inverted ? GPIOF_ACTIVE_LOW : 0;
2363 		gpio = mach->gpio_pullup;
2364 		if (gpio_is_valid(gpio)) {
2365 			retval = devm_gpio_request_one(&pdev->dev, gpio,
2366 						       gpio_flags,
2367 						       "USB D+ pullup");
2368 			if (retval)
2369 				return retval;
2370 			udc->gpiod = gpio_to_desc(mach->gpio_pullup);
2371 		}
2372 		udc->udc_command = mach->udc_command;
2373 	} else {
2374 		udc->gpiod = devm_gpiod_get(&pdev->dev, NULL, GPIOD_ASIS);
2375 	}
2376 
2377 	udc->regs = devm_platform_ioremap_resource(pdev, 0);
2378 	if (IS_ERR(udc->regs))
2379 		return PTR_ERR(udc->regs);
2380 	udc->irq = platform_get_irq(pdev, 0);
2381 	if (udc->irq < 0)
2382 		return udc->irq;
2383 
2384 	udc->dev = &pdev->dev;
2385 	if (of_have_populated_dt()) {
2386 		udc->transceiver =
2387 			devm_usb_get_phy_by_phandle(udc->dev, "phys", 0);
2388 		if (IS_ERR(udc->transceiver))
2389 			return PTR_ERR(udc->transceiver);
2390 	} else {
2391 		udc->transceiver = usb_get_phy(USB_PHY_TYPE_USB2);
2392 	}
2393 
2394 	if (IS_ERR(udc->gpiod)) {
2395 		dev_err(&pdev->dev, "Couldn't find or request D+ gpio : %ld\n",
2396 			PTR_ERR(udc->gpiod));
2397 		return PTR_ERR(udc->gpiod);
2398 	}
2399 	if (udc->gpiod)
2400 		gpiod_direction_output(udc->gpiod, 0);
2401 
2402 	udc->clk = devm_clk_get(&pdev->dev, NULL);
2403 	if (IS_ERR(udc->clk))
2404 		return PTR_ERR(udc->clk);
2405 
2406 	retval = clk_prepare(udc->clk);
2407 	if (retval)
2408 		return retval;
2409 
2410 	udc->vbus_sensed = 0;
2411 
2412 	the_controller = udc;
2413 	platform_set_drvdata(pdev, udc);
2414 	udc_init_data(udc);
2415 
2416 	/* irq setup after old hardware state is cleaned up */
2417 	retval = devm_request_irq(&pdev->dev, udc->irq, pxa_udc_irq,
2418 				  IRQF_SHARED, driver_name, udc);
2419 	if (retval != 0) {
2420 		dev_err(udc->dev, "%s: can't get irq %i, err %d\n",
2421 			driver_name, udc->irq, retval);
2422 		goto err;
2423 	}
2424 
2425 	if (!IS_ERR_OR_NULL(udc->transceiver))
2426 		usb_register_notifier(udc->transceiver, &pxa27x_udc_phy);
2427 	retval = usb_add_gadget_udc(&pdev->dev, &udc->gadget);
2428 	if (retval)
2429 		goto err_add_gadget;
2430 
2431 	pxa_init_debugfs(udc);
2432 	if (should_enable_udc(udc))
2433 		udc_enable(udc);
2434 	return 0;
2435 
2436 err_add_gadget:
2437 	if (!IS_ERR_OR_NULL(udc->transceiver))
2438 		usb_unregister_notifier(udc->transceiver, &pxa27x_udc_phy);
2439 err:
2440 	clk_unprepare(udc->clk);
2441 	return retval;
2442 }
2443 
2444 /**
2445  * pxa_udc_remove - removes the udc device driver
2446  * @_dev: platform device
2447  */
2448 static void pxa_udc_remove(struct platform_device *_dev)
2449 {
2450 	struct pxa_udc *udc = platform_get_drvdata(_dev);
2451 
2452 	usb_del_gadget_udc(&udc->gadget);
2453 	pxa_cleanup_debugfs(udc);
2454 
2455 	if (!IS_ERR_OR_NULL(udc->transceiver)) {
2456 		usb_unregister_notifier(udc->transceiver, &pxa27x_udc_phy);
2457 		usb_put_phy(udc->transceiver);
2458 	}
2459 
2460 	udc->transceiver = NULL;
2461 	the_controller = NULL;
2462 	clk_unprepare(udc->clk);
2463 }
2464 
2465 static void pxa_udc_shutdown(struct platform_device *_dev)
2466 {
2467 	struct pxa_udc *udc = platform_get_drvdata(_dev);
2468 
2469 	if (udc_readl(udc, UDCCR) & UDCCR_UDE)
2470 		udc_disable(udc);
2471 }
2472 
2473 #ifdef CONFIG_PM
2474 /**
2475  * pxa_udc_suspend - Suspend udc device
2476  * @_dev: platform device
2477  * @state: suspend state
2478  *
2479  * Suspends udc : saves configuration registers (UDCCR*), then disables the udc
2480  * device.
2481  */
2482 static int pxa_udc_suspend(struct platform_device *_dev, pm_message_t state)
2483 {
2484 	struct pxa_udc *udc = platform_get_drvdata(_dev);
2485 	struct pxa_ep *ep;
2486 
2487 	ep = &udc->pxa_ep[0];
2488 	udc->udccsr0 = udc_ep_readl(ep, UDCCSR);
2489 
2490 	udc_disable(udc);
2491 	udc->pullup_resume = udc->pullup_on;
2492 	dplus_pullup(udc, 0);
2493 
2494 	if (udc->driver)
2495 		udc->driver->disconnect(&udc->gadget);
2496 
2497 	return 0;
2498 }
2499 
2500 /**
2501  * pxa_udc_resume - Resume udc device
2502  * @_dev: platform device
2503  *
2504  * Resumes udc : restores configuration registers (UDCCR*), then enables the udc
2505  * device.
2506  */
2507 static int pxa_udc_resume(struct platform_device *_dev)
2508 {
2509 	struct pxa_udc *udc = platform_get_drvdata(_dev);
2510 	struct pxa_ep *ep;
2511 
2512 	ep = &udc->pxa_ep[0];
2513 	udc_ep_writel(ep, UDCCSR, udc->udccsr0 & (UDCCSR0_FST | UDCCSR0_DME));
2514 
2515 	dplus_pullup(udc, udc->pullup_resume);
2516 	if (should_enable_udc(udc))
2517 		udc_enable(udc);
2518 	/*
2519 	 * We do not handle OTG yet.
2520 	 *
2521 	 * OTGPH bit is set when sleep mode is entered.
2522 	 * it indicates that OTG pad is retaining its state.
2523 	 * Upon exit from sleep mode and before clearing OTGPH,
2524 	 * Software must configure the USB OTG pad, UDC, and UHC
2525 	 * to the state they were in before entering sleep mode.
2526 	 */
2527 	pxa27x_clear_otgph();
2528 
2529 	return 0;
2530 }
2531 #endif
2532 
2533 /* work with hotplug and coldplug */
2534 MODULE_ALIAS("platform:pxa27x-udc");
2535 
2536 static struct platform_driver udc_driver = {
2537 	.driver		= {
2538 		.name	= "pxa27x-udc",
2539 		.of_match_table = of_match_ptr(udc_pxa_dt_ids),
2540 	},
2541 	.probe		= pxa_udc_probe,
2542 	.remove_new	= pxa_udc_remove,
2543 	.shutdown	= pxa_udc_shutdown,
2544 #ifdef CONFIG_PM
2545 	.suspend	= pxa_udc_suspend,
2546 	.resume		= pxa_udc_resume
2547 #endif
2548 };
2549 
2550 module_platform_driver(udc_driver);
2551 
2552 MODULE_DESCRIPTION(DRIVER_DESC);
2553 MODULE_AUTHOR("Robert Jarzmik");
2554 MODULE_LICENSE("GPL");
2555