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_device.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 	udc->debugfs_root = root;
212 
213 	debugfs_create_file("udcstate", 0400, root, udc, &state_dbg_fops);
214 	debugfs_create_file("queues", 0400, root, udc, &queues_dbg_fops);
215 	debugfs_create_file("epstate", 0400, root, udc, &eps_dbg_fops);
216 }
217 
218 static void pxa_cleanup_debugfs(struct pxa_udc *udc)
219 {
220 	debugfs_remove_recursive(udc->debugfs_root);
221 }
222 
223 #else
224 static inline void pxa_init_debugfs(struct pxa_udc *udc)
225 {
226 }
227 
228 static inline void pxa_cleanup_debugfs(struct pxa_udc *udc)
229 {
230 }
231 #endif
232 
233 /**
234  * is_match_usb_pxa - check if usb_ep and pxa_ep match
235  * @udc_usb_ep: usb endpoint
236  * @ep: pxa endpoint
237  * @config: configuration required in pxa_ep
238  * @interface: interface required in pxa_ep
239  * @altsetting: altsetting required in pxa_ep
240  *
241  * Returns 1 if all criteria match between pxa and usb endpoint, 0 otherwise
242  */
243 static int is_match_usb_pxa(struct udc_usb_ep *udc_usb_ep, struct pxa_ep *ep,
244 		int config, int interface, int altsetting)
245 {
246 	if (usb_endpoint_num(&udc_usb_ep->desc) != ep->addr)
247 		return 0;
248 	if (usb_endpoint_dir_in(&udc_usb_ep->desc) != ep->dir_in)
249 		return 0;
250 	if (usb_endpoint_type(&udc_usb_ep->desc) != ep->type)
251 		return 0;
252 	if ((ep->config != config) || (ep->interface != interface)
253 			|| (ep->alternate != altsetting))
254 		return 0;
255 	return 1;
256 }
257 
258 /**
259  * find_pxa_ep - find pxa_ep structure matching udc_usb_ep
260  * @udc: pxa udc
261  * @udc_usb_ep: udc_usb_ep structure
262  *
263  * Match udc_usb_ep and all pxa_ep available, to see if one matches.
264  * This is necessary because of the strong pxa hardware restriction requiring
265  * that once pxa endpoints are initialized, their configuration is freezed, and
266  * no change can be made to their address, direction, or in which configuration,
267  * interface or altsetting they are active ... which differs from more usual
268  * models which have endpoints be roughly just addressable fifos, and leave
269  * configuration events up to gadget drivers (like all control messages).
270  *
271  * Note that there is still a blurred point here :
272  *   - we rely on UDCCR register "active interface" and "active altsetting".
273  *     This is a nonsense in regard of USB spec, where multiple interfaces are
274  *     active at the same time.
275  *   - if we knew for sure that the pxa can handle multiple interface at the
276  *     same time, assuming Intel's Developer Guide is wrong, this function
277  *     should be reviewed, and a cache of couples (iface, altsetting) should
278  *     be kept in the pxa_udc structure. In this case this function would match
279  *     against the cache of couples instead of the "last altsetting" set up.
280  *
281  * Returns the matched pxa_ep structure or NULL if none found
282  */
283 static struct pxa_ep *find_pxa_ep(struct pxa_udc *udc,
284 		struct udc_usb_ep *udc_usb_ep)
285 {
286 	int i;
287 	struct pxa_ep *ep;
288 	int cfg = udc->config;
289 	int iface = udc->last_interface;
290 	int alt = udc->last_alternate;
291 
292 	if (udc_usb_ep == &udc->udc_usb_ep[0])
293 		return &udc->pxa_ep[0];
294 
295 	for (i = 1; i < NR_PXA_ENDPOINTS; i++) {
296 		ep = &udc->pxa_ep[i];
297 		if (is_match_usb_pxa(udc_usb_ep, ep, cfg, iface, alt))
298 			return ep;
299 	}
300 	return NULL;
301 }
302 
303 /**
304  * update_pxa_ep_matches - update pxa_ep cached values in all udc_usb_ep
305  * @udc: pxa udc
306  *
307  * Context: interrupt handler
308  *
309  * Updates all pxa_ep fields in udc_usb_ep structures, if this field was
310  * previously set up (and is not NULL). The update is necessary is a
311  * configuration change or altsetting change was issued by the USB host.
312  */
313 static void update_pxa_ep_matches(struct pxa_udc *udc)
314 {
315 	int i;
316 	struct udc_usb_ep *udc_usb_ep;
317 
318 	for (i = 1; i < NR_USB_ENDPOINTS; i++) {
319 		udc_usb_ep = &udc->udc_usb_ep[i];
320 		if (udc_usb_ep->pxa_ep)
321 			udc_usb_ep->pxa_ep = find_pxa_ep(udc, udc_usb_ep);
322 	}
323 }
324 
325 /**
326  * pio_irq_enable - Enables irq generation for one endpoint
327  * @ep: udc endpoint
328  */
329 static void pio_irq_enable(struct pxa_ep *ep)
330 {
331 	struct pxa_udc *udc = ep->dev;
332 	int index = EPIDX(ep);
333 	u32 udcicr0 = udc_readl(udc, UDCICR0);
334 	u32 udcicr1 = udc_readl(udc, UDCICR1);
335 
336 	if (index < 16)
337 		udc_writel(udc, UDCICR0, udcicr0 | (3 << (index * 2)));
338 	else
339 		udc_writel(udc, UDCICR1, udcicr1 | (3 << ((index - 16) * 2)));
340 }
341 
342 /**
343  * pio_irq_disable - Disables irq generation for one endpoint
344  * @ep: udc endpoint
345  */
346 static void pio_irq_disable(struct pxa_ep *ep)
347 {
348 	struct pxa_udc *udc = ep->dev;
349 	int index = EPIDX(ep);
350 	u32 udcicr0 = udc_readl(udc, UDCICR0);
351 	u32 udcicr1 = udc_readl(udc, UDCICR1);
352 
353 	if (index < 16)
354 		udc_writel(udc, UDCICR0, udcicr0 & ~(3 << (index * 2)));
355 	else
356 		udc_writel(udc, UDCICR1, udcicr1 & ~(3 << ((index - 16) * 2)));
357 }
358 
359 /**
360  * udc_set_mask_UDCCR - set bits in UDCCR
361  * @udc: udc device
362  * @mask: bits to set in UDCCR
363  *
364  * Sets bits in UDCCR, leaving DME and FST bits as they were.
365  */
366 static inline void udc_set_mask_UDCCR(struct pxa_udc *udc, int mask)
367 {
368 	u32 udccr = udc_readl(udc, UDCCR);
369 	udc_writel(udc, UDCCR,
370 			(udccr & UDCCR_MASK_BITS) | (mask & UDCCR_MASK_BITS));
371 }
372 
373 /**
374  * udc_clear_mask_UDCCR - clears bits in UDCCR
375  * @udc: udc device
376  * @mask: bit to clear in UDCCR
377  *
378  * Clears bits in UDCCR, leaving DME and FST bits as they were.
379  */
380 static inline void udc_clear_mask_UDCCR(struct pxa_udc *udc, int mask)
381 {
382 	u32 udccr = udc_readl(udc, UDCCR);
383 	udc_writel(udc, UDCCR,
384 			(udccr & UDCCR_MASK_BITS) & ~(mask & UDCCR_MASK_BITS));
385 }
386 
387 /**
388  * ep_write_UDCCSR - set bits in UDCCSR
389  * @ep: udc endpoint
390  * @mask: bits to set in UDCCR
391  *
392  * Sets bits in UDCCSR (UDCCSR0 and UDCCSR*).
393  *
394  * A specific case is applied to ep0 : the ACM bit is always set to 1, for
395  * SET_INTERFACE and SET_CONFIGURATION.
396  */
397 static inline void ep_write_UDCCSR(struct pxa_ep *ep, int mask)
398 {
399 	if (is_ep0(ep))
400 		mask |= UDCCSR0_ACM;
401 	udc_ep_writel(ep, UDCCSR, mask);
402 }
403 
404 /**
405  * ep_count_bytes_remain - get how many bytes in udc endpoint
406  * @ep: udc endpoint
407  *
408  * Returns number of bytes in OUT fifos. Broken for IN fifos (-EOPNOTSUPP)
409  */
410 static int ep_count_bytes_remain(struct pxa_ep *ep)
411 {
412 	if (ep->dir_in)
413 		return -EOPNOTSUPP;
414 	return udc_ep_readl(ep, UDCBCR) & 0x3ff;
415 }
416 
417 /**
418  * ep_is_empty - checks if ep has byte ready for reading
419  * @ep: udc endpoint
420  *
421  * If endpoint is the control endpoint, checks if there are bytes in the
422  * control endpoint fifo. If endpoint is a data endpoint, checks if bytes
423  * are ready for reading on OUT endpoint.
424  *
425  * Returns 0 if ep not empty, 1 if ep empty, -EOPNOTSUPP if IN endpoint
426  */
427 static int ep_is_empty(struct pxa_ep *ep)
428 {
429 	int ret;
430 
431 	if (!is_ep0(ep) && ep->dir_in)
432 		return -EOPNOTSUPP;
433 	if (is_ep0(ep))
434 		ret = !(udc_ep_readl(ep, UDCCSR) & UDCCSR0_RNE);
435 	else
436 		ret = !(udc_ep_readl(ep, UDCCSR) & UDCCSR_BNE);
437 	return ret;
438 }
439 
440 /**
441  * ep_is_full - checks if ep has place to write bytes
442  * @ep: udc endpoint
443  *
444  * If endpoint is not the control endpoint and is an IN endpoint, checks if
445  * there is place to write bytes into the endpoint.
446  *
447  * Returns 0 if ep not full, 1 if ep full, -EOPNOTSUPP if OUT endpoint
448  */
449 static int ep_is_full(struct pxa_ep *ep)
450 {
451 	if (is_ep0(ep))
452 		return (udc_ep_readl(ep, UDCCSR) & UDCCSR0_IPR);
453 	if (!ep->dir_in)
454 		return -EOPNOTSUPP;
455 	return (!(udc_ep_readl(ep, UDCCSR) & UDCCSR_BNF));
456 }
457 
458 /**
459  * epout_has_pkt - checks if OUT endpoint fifo has a packet available
460  * @ep: pxa endpoint
461  *
462  * Returns 1 if a complete packet is available, 0 if not, -EOPNOTSUPP for IN ep.
463  */
464 static int epout_has_pkt(struct pxa_ep *ep)
465 {
466 	if (!is_ep0(ep) && ep->dir_in)
467 		return -EOPNOTSUPP;
468 	if (is_ep0(ep))
469 		return (udc_ep_readl(ep, UDCCSR) & UDCCSR0_OPC);
470 	return (udc_ep_readl(ep, UDCCSR) & UDCCSR_PC);
471 }
472 
473 /**
474  * set_ep0state - Set ep0 automata state
475  * @udc: udc device
476  * @state: state
477  */
478 static void set_ep0state(struct pxa_udc *udc, int state)
479 {
480 	struct pxa_ep *ep = &udc->pxa_ep[0];
481 	char *old_stname = EP0_STNAME(udc);
482 
483 	udc->ep0state = state;
484 	ep_dbg(ep, "state=%s->%s, udccsr0=0x%03x, udcbcr=%d\n", old_stname,
485 		EP0_STNAME(udc), udc_ep_readl(ep, UDCCSR),
486 		udc_ep_readl(ep, UDCBCR));
487 }
488 
489 /**
490  * ep0_idle - Put control endpoint into idle state
491  * @dev: udc device
492  */
493 static void ep0_idle(struct pxa_udc *dev)
494 {
495 	set_ep0state(dev, WAIT_FOR_SETUP);
496 }
497 
498 /**
499  * inc_ep_stats_reqs - Update ep stats counts
500  * @ep: physical endpoint
501  * @is_in: ep direction (USB_DIR_IN or 0)
502  *
503  */
504 static void inc_ep_stats_reqs(struct pxa_ep *ep, int is_in)
505 {
506 	if (is_in)
507 		ep->stats.in_ops++;
508 	else
509 		ep->stats.out_ops++;
510 }
511 
512 /**
513  * inc_ep_stats_bytes - Update ep stats counts
514  * @ep: physical endpoint
515  * @count: bytes transferred on endpoint
516  * @is_in: ep direction (USB_DIR_IN or 0)
517  */
518 static void inc_ep_stats_bytes(struct pxa_ep *ep, int count, int is_in)
519 {
520 	if (is_in)
521 		ep->stats.in_bytes += count;
522 	else
523 		ep->stats.out_bytes += count;
524 }
525 
526 /**
527  * pxa_ep_setup - Sets up an usb physical endpoint
528  * @ep: pxa27x physical endpoint
529  *
530  * Find the physical pxa27x ep, and setup its UDCCR
531  */
532 static void pxa_ep_setup(struct pxa_ep *ep)
533 {
534 	u32 new_udccr;
535 
536 	new_udccr = ((ep->config << UDCCONR_CN_S) & UDCCONR_CN)
537 		| ((ep->interface << UDCCONR_IN_S) & UDCCONR_IN)
538 		| ((ep->alternate << UDCCONR_AISN_S) & UDCCONR_AISN)
539 		| ((EPADDR(ep) << UDCCONR_EN_S) & UDCCONR_EN)
540 		| ((EPXFERTYPE(ep) << UDCCONR_ET_S) & UDCCONR_ET)
541 		| ((ep->dir_in) ? UDCCONR_ED : 0)
542 		| ((ep->fifo_size << UDCCONR_MPS_S) & UDCCONR_MPS)
543 		| UDCCONR_EE;
544 
545 	udc_ep_writel(ep, UDCCR, new_udccr);
546 }
547 
548 /**
549  * pxa_eps_setup - Sets up all usb physical endpoints
550  * @dev: udc device
551  *
552  * Setup all pxa physical endpoints, except ep0
553  */
554 static void pxa_eps_setup(struct pxa_udc *dev)
555 {
556 	unsigned int i;
557 
558 	dev_dbg(dev->dev, "%s: dev=%p\n", __func__, dev);
559 
560 	for (i = 1; i < NR_PXA_ENDPOINTS; i++)
561 		pxa_ep_setup(&dev->pxa_ep[i]);
562 }
563 
564 /**
565  * pxa_ep_alloc_request - Allocate usb request
566  * @_ep: usb endpoint
567  * @gfp_flags:
568  *
569  * For the pxa27x, these can just wrap kmalloc/kfree.  gadget drivers
570  * must still pass correctly initialized endpoints, since other controller
571  * drivers may care about how it's currently set up (dma issues etc).
572   */
573 static struct usb_request *
574 pxa_ep_alloc_request(struct usb_ep *_ep, gfp_t gfp_flags)
575 {
576 	struct pxa27x_request *req;
577 
578 	req = kzalloc(sizeof *req, gfp_flags);
579 	if (!req)
580 		return NULL;
581 
582 	INIT_LIST_HEAD(&req->queue);
583 	req->in_use = 0;
584 	req->udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
585 
586 	return &req->req;
587 }
588 
589 /**
590  * pxa_ep_free_request - Free usb request
591  * @_ep: usb endpoint
592  * @_req: usb request
593  *
594  * Wrapper around kfree to free _req
595  */
596 static void pxa_ep_free_request(struct usb_ep *_ep, struct usb_request *_req)
597 {
598 	struct pxa27x_request *req;
599 
600 	req = container_of(_req, struct pxa27x_request, req);
601 	WARN_ON(!list_empty(&req->queue));
602 	kfree(req);
603 }
604 
605 /**
606  * ep_add_request - add a request to the endpoint's queue
607  * @ep: usb endpoint
608  * @req: usb request
609  *
610  * Context: ep->lock held
611  *
612  * Queues the request in the endpoint's queue, and enables the interrupts
613  * on the endpoint.
614  */
615 static void ep_add_request(struct pxa_ep *ep, struct pxa27x_request *req)
616 {
617 	if (unlikely(!req))
618 		return;
619 	ep_vdbg(ep, "req:%p, lg=%d, udccsr=0x%03x\n", req,
620 		req->req.length, udc_ep_readl(ep, UDCCSR));
621 
622 	req->in_use = 1;
623 	list_add_tail(&req->queue, &ep->queue);
624 	pio_irq_enable(ep);
625 }
626 
627 /**
628  * ep_del_request - removes a request from the endpoint's queue
629  * @ep: usb endpoint
630  * @req: usb request
631  *
632  * Context: ep->lock held
633  *
634  * Unqueue the request from the endpoint's queue. If there are no more requests
635  * on the endpoint, and if it's not the control endpoint, interrupts are
636  * disabled on the endpoint.
637  */
638 static void ep_del_request(struct pxa_ep *ep, struct pxa27x_request *req)
639 {
640 	if (unlikely(!req))
641 		return;
642 	ep_vdbg(ep, "req:%p, lg=%d, udccsr=0x%03x\n", req,
643 		req->req.length, udc_ep_readl(ep, UDCCSR));
644 
645 	list_del_init(&req->queue);
646 	req->in_use = 0;
647 	if (!is_ep0(ep) && list_empty(&ep->queue))
648 		pio_irq_disable(ep);
649 }
650 
651 /**
652  * req_done - Complete an usb request
653  * @ep: pxa physical endpoint
654  * @req: pxa request
655  * @status: usb request status sent to gadget API
656  * @pflags: flags of previous spinlock_irq_save() or NULL if no lock held
657  *
658  * Context: ep->lock held if flags not NULL, else ep->lock released
659  *
660  * Retire a pxa27x usb request. Endpoint must be locked.
661  */
662 static void req_done(struct pxa_ep *ep, struct pxa27x_request *req, int status,
663 	unsigned long *pflags)
664 {
665 	unsigned long	flags;
666 
667 	ep_del_request(ep, req);
668 	if (likely(req->req.status == -EINPROGRESS))
669 		req->req.status = status;
670 	else
671 		status = req->req.status;
672 
673 	if (status && status != -ESHUTDOWN)
674 		ep_dbg(ep, "complete req %p stat %d len %u/%u\n",
675 			&req->req, status,
676 			req->req.actual, req->req.length);
677 
678 	if (pflags)
679 		spin_unlock_irqrestore(&ep->lock, *pflags);
680 	local_irq_save(flags);
681 	usb_gadget_giveback_request(&req->udc_usb_ep->usb_ep, &req->req);
682 	local_irq_restore(flags);
683 	if (pflags)
684 		spin_lock_irqsave(&ep->lock, *pflags);
685 }
686 
687 /**
688  * ep_end_out_req - Ends endpoint OUT request
689  * @ep: physical endpoint
690  * @req: pxa request
691  * @pflags: flags of previous spinlock_irq_save() or NULL if no lock held
692  *
693  * Context: ep->lock held or released (see req_done())
694  *
695  * Ends endpoint OUT request (completes usb request).
696  */
697 static void ep_end_out_req(struct pxa_ep *ep, struct pxa27x_request *req,
698 	unsigned long *pflags)
699 {
700 	inc_ep_stats_reqs(ep, !USB_DIR_IN);
701 	req_done(ep, req, 0, pflags);
702 }
703 
704 /**
705  * ep0_end_out_req - Ends control endpoint OUT request (ends data stage)
706  * @ep: physical endpoint
707  * @req: pxa request
708  * @pflags: flags of previous spinlock_irq_save() or NULL if no lock held
709  *
710  * Context: ep->lock held or released (see req_done())
711  *
712  * Ends control endpoint OUT request (completes usb request), and puts
713  * control endpoint into idle state
714  */
715 static void ep0_end_out_req(struct pxa_ep *ep, struct pxa27x_request *req,
716 	unsigned long *pflags)
717 {
718 	set_ep0state(ep->dev, OUT_STATUS_STAGE);
719 	ep_end_out_req(ep, req, pflags);
720 	ep0_idle(ep->dev);
721 }
722 
723 /**
724  * ep_end_in_req - Ends endpoint IN request
725  * @ep: physical endpoint
726  * @req: pxa request
727  * @pflags: flags of previous spinlock_irq_save() or NULL if no lock held
728  *
729  * Context: ep->lock held or released (see req_done())
730  *
731  * Ends endpoint IN request (completes usb request).
732  */
733 static void ep_end_in_req(struct pxa_ep *ep, struct pxa27x_request *req,
734 	unsigned long *pflags)
735 {
736 	inc_ep_stats_reqs(ep, USB_DIR_IN);
737 	req_done(ep, req, 0, pflags);
738 }
739 
740 /**
741  * ep0_end_in_req - Ends control endpoint IN request (ends data stage)
742  * @ep: physical endpoint
743  * @req: pxa request
744  * @pflags: flags of previous spinlock_irq_save() or NULL if no lock held
745  *
746  * Context: ep->lock held or released (see req_done())
747  *
748  * Ends control endpoint IN request (completes usb request), and puts
749  * control endpoint into status state
750  */
751 static void ep0_end_in_req(struct pxa_ep *ep, struct pxa27x_request *req,
752 	unsigned long *pflags)
753 {
754 	set_ep0state(ep->dev, IN_STATUS_STAGE);
755 	ep_end_in_req(ep, req, pflags);
756 }
757 
758 /**
759  * nuke - Dequeue all requests
760  * @ep: pxa endpoint
761  * @status: usb request status
762  *
763  * Context: ep->lock released
764  *
765  * Dequeues all requests on an endpoint. As a side effect, interrupts will be
766  * disabled on that endpoint (because no more requests).
767  */
768 static void nuke(struct pxa_ep *ep, int status)
769 {
770 	struct pxa27x_request	*req;
771 	unsigned long		flags;
772 
773 	spin_lock_irqsave(&ep->lock, flags);
774 	while (!list_empty(&ep->queue)) {
775 		req = list_entry(ep->queue.next, struct pxa27x_request, queue);
776 		req_done(ep, req, status, &flags);
777 	}
778 	spin_unlock_irqrestore(&ep->lock, flags);
779 }
780 
781 /**
782  * read_packet - transfer 1 packet from an OUT endpoint into request
783  * @ep: pxa physical endpoint
784  * @req: usb request
785  *
786  * Takes bytes from OUT endpoint and transfers them info the usb request.
787  * If there is less space in request than bytes received in OUT endpoint,
788  * bytes are left in the OUT endpoint.
789  *
790  * Returns how many bytes were actually transferred
791  */
792 static int read_packet(struct pxa_ep *ep, struct pxa27x_request *req)
793 {
794 	u32 *buf;
795 	int bytes_ep, bufferspace, count, i;
796 
797 	bytes_ep = ep_count_bytes_remain(ep);
798 	bufferspace = req->req.length - req->req.actual;
799 
800 	buf = (u32 *)(req->req.buf + req->req.actual);
801 	prefetchw(buf);
802 
803 	if (likely(!ep_is_empty(ep)))
804 		count = min(bytes_ep, bufferspace);
805 	else /* zlp */
806 		count = 0;
807 
808 	for (i = count; i > 0; i -= 4)
809 		*buf++ = udc_ep_readl(ep, UDCDR);
810 	req->req.actual += count;
811 
812 	ep_write_UDCCSR(ep, UDCCSR_PC);
813 
814 	return count;
815 }
816 
817 /**
818  * write_packet - transfer 1 packet from request into an IN endpoint
819  * @ep: pxa physical endpoint
820  * @req: usb request
821  * @max: max bytes that fit into endpoint
822  *
823  * Takes bytes from usb request, and transfers them into the physical
824  * endpoint. If there are no bytes to transfer, doesn't write anything
825  * to physical endpoint.
826  *
827  * Returns how many bytes were actually transferred.
828  */
829 static int write_packet(struct pxa_ep *ep, struct pxa27x_request *req,
830 			unsigned int max)
831 {
832 	int length, count, remain, i;
833 	u32 *buf;
834 	u8 *buf_8;
835 
836 	buf = (u32 *)(req->req.buf + req->req.actual);
837 	prefetch(buf);
838 
839 	length = min(req->req.length - req->req.actual, max);
840 	req->req.actual += length;
841 
842 	remain = length & 0x3;
843 	count = length & ~(0x3);
844 	for (i = count; i > 0 ; i -= 4)
845 		udc_ep_writel(ep, UDCDR, *buf++);
846 
847 	buf_8 = (u8 *)buf;
848 	for (i = remain; i > 0; i--)
849 		udc_ep_writeb(ep, UDCDR, *buf_8++);
850 
851 	ep_vdbg(ep, "length=%d+%d, udccsr=0x%03x\n", count, remain,
852 		udc_ep_readl(ep, UDCCSR));
853 
854 	return length;
855 }
856 
857 /**
858  * read_fifo - Transfer packets from OUT endpoint into usb request
859  * @ep: pxa physical endpoint
860  * @req: usb request
861  *
862  * Context: interrupt handler
863  *
864  * Unload as many packets as possible from the fifo we use for usb OUT
865  * transfers and put them into the request. Caller should have made sure
866  * there's at least one packet ready.
867  * Doesn't complete the request, that's the caller's job
868  *
869  * Returns 1 if the request completed, 0 otherwise
870  */
871 static int read_fifo(struct pxa_ep *ep, struct pxa27x_request *req)
872 {
873 	int count, is_short, completed = 0;
874 
875 	while (epout_has_pkt(ep)) {
876 		count = read_packet(ep, req);
877 		inc_ep_stats_bytes(ep, count, !USB_DIR_IN);
878 
879 		is_short = (count < ep->fifo_size);
880 		ep_dbg(ep, "read udccsr:%03x, count:%d bytes%s req %p %d/%d\n",
881 			udc_ep_readl(ep, UDCCSR), count, is_short ? "/S" : "",
882 			&req->req, req->req.actual, req->req.length);
883 
884 		/* completion */
885 		if (is_short || req->req.actual == req->req.length) {
886 			completed = 1;
887 			break;
888 		}
889 		/* finished that packet.  the next one may be waiting... */
890 	}
891 	return completed;
892 }
893 
894 /**
895  * write_fifo - transfer packets from usb request into an IN endpoint
896  * @ep: pxa physical endpoint
897  * @req: pxa usb request
898  *
899  * Write to an IN endpoint fifo, as many packets as possible.
900  * irqs will use this to write the rest later.
901  * caller guarantees at least one packet buffer is ready (or a zlp).
902  * Doesn't complete the request, that's the caller's job
903  *
904  * Returns 1 if request fully transferred, 0 if partial transfer
905  */
906 static int write_fifo(struct pxa_ep *ep, struct pxa27x_request *req)
907 {
908 	unsigned max;
909 	int count, is_short, is_last = 0, completed = 0, totcount = 0;
910 	u32 udccsr;
911 
912 	max = ep->fifo_size;
913 	do {
914 		udccsr = udc_ep_readl(ep, UDCCSR);
915 		if (udccsr & UDCCSR_PC) {
916 			ep_vdbg(ep, "Clearing Transmit Complete, udccsr=%x\n",
917 				udccsr);
918 			ep_write_UDCCSR(ep, UDCCSR_PC);
919 		}
920 		if (udccsr & UDCCSR_TRN) {
921 			ep_vdbg(ep, "Clearing Underrun on, udccsr=%x\n",
922 				udccsr);
923 			ep_write_UDCCSR(ep, UDCCSR_TRN);
924 		}
925 
926 		count = write_packet(ep, req, max);
927 		inc_ep_stats_bytes(ep, count, USB_DIR_IN);
928 		totcount += count;
929 
930 		/* last packet is usually short (or a zlp) */
931 		if (unlikely(count < max)) {
932 			is_last = 1;
933 			is_short = 1;
934 		} else {
935 			if (likely(req->req.length > req->req.actual)
936 					|| req->req.zero)
937 				is_last = 0;
938 			else
939 				is_last = 1;
940 			/* interrupt/iso maxpacket may not fill the fifo */
941 			is_short = unlikely(max < ep->fifo_size);
942 		}
943 
944 		if (is_short)
945 			ep_write_UDCCSR(ep, UDCCSR_SP);
946 
947 		/* requests complete when all IN data is in the FIFO */
948 		if (is_last) {
949 			completed = 1;
950 			break;
951 		}
952 	} while (!ep_is_full(ep));
953 
954 	ep_dbg(ep, "wrote count:%d bytes%s%s, left:%d req=%p\n",
955 			totcount, is_last ? "/L" : "", is_short ? "/S" : "",
956 			req->req.length - req->req.actual, &req->req);
957 
958 	return completed;
959 }
960 
961 /**
962  * read_ep0_fifo - Transfer packets from control endpoint into usb request
963  * @ep: control endpoint
964  * @req: pxa usb request
965  *
966  * Special ep0 version of the above read_fifo. Reads as many bytes from control
967  * endpoint as can be read, and stores them into usb request (limited by request
968  * maximum length).
969  *
970  * Returns 0 if usb request only partially filled, 1 if fully filled
971  */
972 static int read_ep0_fifo(struct pxa_ep *ep, struct pxa27x_request *req)
973 {
974 	int count, is_short, completed = 0;
975 
976 	while (epout_has_pkt(ep)) {
977 		count = read_packet(ep, req);
978 		ep_write_UDCCSR(ep, UDCCSR0_OPC);
979 		inc_ep_stats_bytes(ep, count, !USB_DIR_IN);
980 
981 		is_short = (count < ep->fifo_size);
982 		ep_dbg(ep, "read udccsr:%03x, count:%d bytes%s req %p %d/%d\n",
983 			udc_ep_readl(ep, UDCCSR), count, is_short ? "/S" : "",
984 			&req->req, req->req.actual, req->req.length);
985 
986 		if (is_short || req->req.actual >= req->req.length) {
987 			completed = 1;
988 			break;
989 		}
990 	}
991 
992 	return completed;
993 }
994 
995 /**
996  * write_ep0_fifo - Send a request to control endpoint (ep0 in)
997  * @ep: control endpoint
998  * @req: request
999  *
1000  * Context: interrupt handler
1001  *
1002  * Sends a request (or a part of the request) to the control endpoint (ep0 in).
1003  * If the request doesn't fit, the remaining part will be sent from irq.
1004  * The request is considered fully written only if either :
1005  *   - last write transferred all remaining bytes, but fifo was not fully filled
1006  *   - last write was a 0 length write
1007  *
1008  * Returns 1 if request fully written, 0 if request only partially sent
1009  */
1010 static int write_ep0_fifo(struct pxa_ep *ep, struct pxa27x_request *req)
1011 {
1012 	unsigned	count;
1013 	int		is_last, is_short;
1014 
1015 	count = write_packet(ep, req, EP0_FIFO_SIZE);
1016 	inc_ep_stats_bytes(ep, count, USB_DIR_IN);
1017 
1018 	is_short = (count < EP0_FIFO_SIZE);
1019 	is_last = ((count == 0) || (count < EP0_FIFO_SIZE));
1020 
1021 	/* Sends either a short packet or a 0 length packet */
1022 	if (unlikely(is_short))
1023 		ep_write_UDCCSR(ep, UDCCSR0_IPR);
1024 
1025 	ep_dbg(ep, "in %d bytes%s%s, %d left, req=%p, udccsr0=0x%03x\n",
1026 		count, is_short ? "/S" : "", is_last ? "/L" : "",
1027 		req->req.length - req->req.actual,
1028 		&req->req, udc_ep_readl(ep, UDCCSR));
1029 
1030 	return is_last;
1031 }
1032 
1033 /**
1034  * pxa_ep_queue - Queue a request into an IN endpoint
1035  * @_ep: usb endpoint
1036  * @_req: usb request
1037  * @gfp_flags: flags
1038  *
1039  * Context: thread context or from the interrupt handler in the
1040  * special case of ep0 setup :
1041  *   (irq->handle_ep0_ctrl_req->gadget_setup->pxa_ep_queue)
1042  *
1043  * Returns 0 if succedeed, error otherwise
1044  */
1045 static int pxa_ep_queue(struct usb_ep *_ep, struct usb_request *_req,
1046 			gfp_t gfp_flags)
1047 {
1048 	struct udc_usb_ep	*udc_usb_ep;
1049 	struct pxa_ep		*ep;
1050 	struct pxa27x_request	*req;
1051 	struct pxa_udc		*dev;
1052 	unsigned long		flags;
1053 	int			rc = 0;
1054 	int			is_first_req;
1055 	unsigned		length;
1056 	int			recursion_detected;
1057 
1058 	req = container_of(_req, struct pxa27x_request, req);
1059 	udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
1060 
1061 	if (unlikely(!_req || !_req->complete || !_req->buf))
1062 		return -EINVAL;
1063 
1064 	if (unlikely(!_ep))
1065 		return -EINVAL;
1066 
1067 	ep = udc_usb_ep->pxa_ep;
1068 	if (unlikely(!ep))
1069 		return -EINVAL;
1070 
1071 	dev = ep->dev;
1072 	if (unlikely(!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN)) {
1073 		ep_dbg(ep, "bogus device state\n");
1074 		return -ESHUTDOWN;
1075 	}
1076 
1077 	/* iso is always one packet per request, that's the only way
1078 	 * we can report per-packet status.  that also helps with dma.
1079 	 */
1080 	if (unlikely(EPXFERTYPE_is_ISO(ep)
1081 			&& req->req.length > ep->fifo_size))
1082 		return -EMSGSIZE;
1083 
1084 	spin_lock_irqsave(&ep->lock, flags);
1085 	recursion_detected = ep->in_handle_ep;
1086 
1087 	is_first_req = list_empty(&ep->queue);
1088 	ep_dbg(ep, "queue req %p(first=%s), len %d buf %p\n",
1089 			_req, is_first_req ? "yes" : "no",
1090 			_req->length, _req->buf);
1091 
1092 	if (!ep->enabled) {
1093 		_req->status = -ESHUTDOWN;
1094 		rc = -ESHUTDOWN;
1095 		goto out_locked;
1096 	}
1097 
1098 	if (req->in_use) {
1099 		ep_err(ep, "refusing to queue req %p (already queued)\n", req);
1100 		goto out_locked;
1101 	}
1102 
1103 	length = _req->length;
1104 	_req->status = -EINPROGRESS;
1105 	_req->actual = 0;
1106 
1107 	ep_add_request(ep, req);
1108 	spin_unlock_irqrestore(&ep->lock, flags);
1109 
1110 	if (is_ep0(ep)) {
1111 		switch (dev->ep0state) {
1112 		case WAIT_ACK_SET_CONF_INTERF:
1113 			if (length == 0) {
1114 				ep_end_in_req(ep, req, NULL);
1115 			} else {
1116 				ep_err(ep, "got a request of %d bytes while"
1117 					"in state WAIT_ACK_SET_CONF_INTERF\n",
1118 					length);
1119 				ep_del_request(ep, req);
1120 				rc = -EL2HLT;
1121 			}
1122 			ep0_idle(ep->dev);
1123 			break;
1124 		case IN_DATA_STAGE:
1125 			if (!ep_is_full(ep))
1126 				if (write_ep0_fifo(ep, req))
1127 					ep0_end_in_req(ep, req, NULL);
1128 			break;
1129 		case OUT_DATA_STAGE:
1130 			if ((length == 0) || !epout_has_pkt(ep))
1131 				if (read_ep0_fifo(ep, req))
1132 					ep0_end_out_req(ep, req, NULL);
1133 			break;
1134 		default:
1135 			ep_err(ep, "odd state %s to send me a request\n",
1136 				EP0_STNAME(ep->dev));
1137 			ep_del_request(ep, req);
1138 			rc = -EL2HLT;
1139 			break;
1140 		}
1141 	} else {
1142 		if (!recursion_detected)
1143 			handle_ep(ep);
1144 	}
1145 
1146 out:
1147 	return rc;
1148 out_locked:
1149 	spin_unlock_irqrestore(&ep->lock, flags);
1150 	goto out;
1151 }
1152 
1153 /**
1154  * pxa_ep_dequeue - Dequeue one request
1155  * @_ep: usb endpoint
1156  * @_req: usb request
1157  *
1158  * Return 0 if no error, -EINVAL or -ECONNRESET otherwise
1159  */
1160 static int pxa_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
1161 {
1162 	struct pxa_ep		*ep;
1163 	struct udc_usb_ep	*udc_usb_ep;
1164 	struct pxa27x_request	*req;
1165 	unsigned long		flags;
1166 	int			rc = -EINVAL;
1167 
1168 	if (!_ep)
1169 		return rc;
1170 	udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
1171 	ep = udc_usb_ep->pxa_ep;
1172 	if (!ep || is_ep0(ep))
1173 		return rc;
1174 
1175 	spin_lock_irqsave(&ep->lock, flags);
1176 
1177 	/* make sure it's actually queued on this endpoint */
1178 	list_for_each_entry(req, &ep->queue, queue) {
1179 		if (&req->req == _req) {
1180 			rc = 0;
1181 			break;
1182 		}
1183 	}
1184 
1185 	spin_unlock_irqrestore(&ep->lock, flags);
1186 	if (!rc)
1187 		req_done(ep, req, -ECONNRESET, NULL);
1188 	return rc;
1189 }
1190 
1191 /**
1192  * pxa_ep_set_halt - Halts operations on one endpoint
1193  * @_ep: usb endpoint
1194  * @value:
1195  *
1196  * Returns 0 if no error, -EINVAL, -EROFS, -EAGAIN otherwise
1197  */
1198 static int pxa_ep_set_halt(struct usb_ep *_ep, int value)
1199 {
1200 	struct pxa_ep		*ep;
1201 	struct udc_usb_ep	*udc_usb_ep;
1202 	unsigned long flags;
1203 	int rc;
1204 
1205 
1206 	if (!_ep)
1207 		return -EINVAL;
1208 	udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
1209 	ep = udc_usb_ep->pxa_ep;
1210 	if (!ep || is_ep0(ep))
1211 		return -EINVAL;
1212 
1213 	if (value == 0) {
1214 		/*
1215 		 * This path (reset toggle+halt) is needed to implement
1216 		 * SET_INTERFACE on normal hardware.  but it can't be
1217 		 * done from software on the PXA UDC, and the hardware
1218 		 * forgets to do it as part of SET_INTERFACE automagic.
1219 		 */
1220 		ep_dbg(ep, "only host can clear halt\n");
1221 		return -EROFS;
1222 	}
1223 
1224 	spin_lock_irqsave(&ep->lock, flags);
1225 
1226 	rc = -EAGAIN;
1227 	if (ep->dir_in	&& (ep_is_full(ep) || !list_empty(&ep->queue)))
1228 		goto out;
1229 
1230 	/* FST, FEF bits are the same for control and non control endpoints */
1231 	rc = 0;
1232 	ep_write_UDCCSR(ep, UDCCSR_FST | UDCCSR_FEF);
1233 	if (is_ep0(ep))
1234 		set_ep0state(ep->dev, STALL);
1235 
1236 out:
1237 	spin_unlock_irqrestore(&ep->lock, flags);
1238 	return rc;
1239 }
1240 
1241 /**
1242  * pxa_ep_fifo_status - Get how many bytes in physical endpoint
1243  * @_ep: usb endpoint
1244  *
1245  * Returns number of bytes in OUT fifos. Broken for IN fifos.
1246  */
1247 static int pxa_ep_fifo_status(struct usb_ep *_ep)
1248 {
1249 	struct pxa_ep		*ep;
1250 	struct udc_usb_ep	*udc_usb_ep;
1251 
1252 	if (!_ep)
1253 		return -ENODEV;
1254 	udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
1255 	ep = udc_usb_ep->pxa_ep;
1256 	if (!ep || is_ep0(ep))
1257 		return -ENODEV;
1258 
1259 	if (ep->dir_in)
1260 		return -EOPNOTSUPP;
1261 	if (ep->dev->gadget.speed == USB_SPEED_UNKNOWN || ep_is_empty(ep))
1262 		return 0;
1263 	else
1264 		return ep_count_bytes_remain(ep) + 1;
1265 }
1266 
1267 /**
1268  * pxa_ep_fifo_flush - Flushes one endpoint
1269  * @_ep: usb endpoint
1270  *
1271  * Discards all data in one endpoint(IN or OUT), except control endpoint.
1272  */
1273 static void pxa_ep_fifo_flush(struct usb_ep *_ep)
1274 {
1275 	struct pxa_ep		*ep;
1276 	struct udc_usb_ep	*udc_usb_ep;
1277 	unsigned long		flags;
1278 
1279 	if (!_ep)
1280 		return;
1281 	udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
1282 	ep = udc_usb_ep->pxa_ep;
1283 	if (!ep || is_ep0(ep))
1284 		return;
1285 
1286 	spin_lock_irqsave(&ep->lock, flags);
1287 
1288 	if (unlikely(!list_empty(&ep->queue)))
1289 		ep_dbg(ep, "called while queue list not empty\n");
1290 	ep_dbg(ep, "called\n");
1291 
1292 	/* for OUT, just read and discard the FIFO contents. */
1293 	if (!ep->dir_in) {
1294 		while (!ep_is_empty(ep))
1295 			udc_ep_readl(ep, UDCDR);
1296 	} else {
1297 		/* most IN status is the same, but ISO can't stall */
1298 		ep_write_UDCCSR(ep,
1299 				UDCCSR_PC | UDCCSR_FEF | UDCCSR_TRN
1300 				| (EPXFERTYPE_is_ISO(ep) ? 0 : UDCCSR_SST));
1301 	}
1302 
1303 	spin_unlock_irqrestore(&ep->lock, flags);
1304 }
1305 
1306 /**
1307  * pxa_ep_enable - Enables usb endpoint
1308  * @_ep: usb endpoint
1309  * @desc: usb endpoint descriptor
1310  *
1311  * Nothing much to do here, as ep configuration is done once and for all
1312  * before udc is enabled. After udc enable, no physical endpoint configuration
1313  * can be changed.
1314  * Function makes sanity checks and flushes the endpoint.
1315  */
1316 static int pxa_ep_enable(struct usb_ep *_ep,
1317 	const struct usb_endpoint_descriptor *desc)
1318 {
1319 	struct pxa_ep		*ep;
1320 	struct udc_usb_ep	*udc_usb_ep;
1321 	struct pxa_udc		*udc;
1322 
1323 	if (!_ep || !desc)
1324 		return -EINVAL;
1325 
1326 	udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
1327 	if (udc_usb_ep->pxa_ep) {
1328 		ep = udc_usb_ep->pxa_ep;
1329 		ep_warn(ep, "usb_ep %s already enabled, doing nothing\n",
1330 			_ep->name);
1331 	} else {
1332 		ep = find_pxa_ep(udc_usb_ep->dev, udc_usb_ep);
1333 	}
1334 
1335 	if (!ep || is_ep0(ep)) {
1336 		dev_err(udc_usb_ep->dev->dev,
1337 			"unable to match pxa_ep for ep %s\n",
1338 			_ep->name);
1339 		return -EINVAL;
1340 	}
1341 
1342 	if ((desc->bDescriptorType != USB_DT_ENDPOINT)
1343 			|| (ep->type != usb_endpoint_type(desc))) {
1344 		ep_err(ep, "type mismatch\n");
1345 		return -EINVAL;
1346 	}
1347 
1348 	if (ep->fifo_size < usb_endpoint_maxp(desc)) {
1349 		ep_err(ep, "bad maxpacket\n");
1350 		return -ERANGE;
1351 	}
1352 
1353 	udc_usb_ep->pxa_ep = ep;
1354 	udc = ep->dev;
1355 
1356 	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
1357 		ep_err(ep, "bogus device state\n");
1358 		return -ESHUTDOWN;
1359 	}
1360 
1361 	ep->enabled = 1;
1362 
1363 	/* flush fifo (mostly for OUT buffers) */
1364 	pxa_ep_fifo_flush(_ep);
1365 
1366 	ep_dbg(ep, "enabled\n");
1367 	return 0;
1368 }
1369 
1370 /**
1371  * pxa_ep_disable - Disable usb endpoint
1372  * @_ep: usb endpoint
1373  *
1374  * Same as for pxa_ep_enable, no physical endpoint configuration can be
1375  * changed.
1376  * Function flushes the endpoint and related requests.
1377  */
1378 static int pxa_ep_disable(struct usb_ep *_ep)
1379 {
1380 	struct pxa_ep		*ep;
1381 	struct udc_usb_ep	*udc_usb_ep;
1382 
1383 	if (!_ep)
1384 		return -EINVAL;
1385 
1386 	udc_usb_ep = container_of(_ep, struct udc_usb_ep, usb_ep);
1387 	ep = udc_usb_ep->pxa_ep;
1388 	if (!ep || is_ep0(ep) || !list_empty(&ep->queue))
1389 		return -EINVAL;
1390 
1391 	ep->enabled = 0;
1392 	nuke(ep, -ESHUTDOWN);
1393 
1394 	pxa_ep_fifo_flush(_ep);
1395 	udc_usb_ep->pxa_ep = NULL;
1396 
1397 	ep_dbg(ep, "disabled\n");
1398 	return 0;
1399 }
1400 
1401 static const struct usb_ep_ops pxa_ep_ops = {
1402 	.enable		= pxa_ep_enable,
1403 	.disable	= pxa_ep_disable,
1404 
1405 	.alloc_request	= pxa_ep_alloc_request,
1406 	.free_request	= pxa_ep_free_request,
1407 
1408 	.queue		= pxa_ep_queue,
1409 	.dequeue	= pxa_ep_dequeue,
1410 
1411 	.set_halt	= pxa_ep_set_halt,
1412 	.fifo_status	= pxa_ep_fifo_status,
1413 	.fifo_flush	= pxa_ep_fifo_flush,
1414 };
1415 
1416 /**
1417  * dplus_pullup - Connect or disconnect pullup resistor to D+ pin
1418  * @udc: udc device
1419  * @on: 0 if disconnect pullup resistor, 1 otherwise
1420  * Context: any
1421  *
1422  * Handle D+ pullup resistor, make the device visible to the usb bus, and
1423  * declare it as a full speed usb device
1424  */
1425 static void dplus_pullup(struct pxa_udc *udc, int on)
1426 {
1427 	if (udc->gpiod) {
1428 		gpiod_set_value(udc->gpiod, on);
1429 	} else if (udc->udc_command) {
1430 		if (on)
1431 			udc->udc_command(PXA2XX_UDC_CMD_CONNECT);
1432 		else
1433 			udc->udc_command(PXA2XX_UDC_CMD_DISCONNECT);
1434 	}
1435 	udc->pullup_on = on;
1436 }
1437 
1438 /**
1439  * pxa_udc_get_frame - Returns usb frame number
1440  * @_gadget: usb gadget
1441  */
1442 static int pxa_udc_get_frame(struct usb_gadget *_gadget)
1443 {
1444 	struct pxa_udc *udc = to_gadget_udc(_gadget);
1445 
1446 	return (udc_readl(udc, UDCFNR) & 0x7ff);
1447 }
1448 
1449 /**
1450  * pxa_udc_wakeup - Force udc device out of suspend
1451  * @_gadget: usb gadget
1452  *
1453  * Returns 0 if successful, error code otherwise
1454  */
1455 static int pxa_udc_wakeup(struct usb_gadget *_gadget)
1456 {
1457 	struct pxa_udc *udc = to_gadget_udc(_gadget);
1458 
1459 	/* host may not have enabled remote wakeup */
1460 	if ((udc_readl(udc, UDCCR) & UDCCR_DWRE) == 0)
1461 		return -EHOSTUNREACH;
1462 	udc_set_mask_UDCCR(udc, UDCCR_UDR);
1463 	return 0;
1464 }
1465 
1466 static void udc_enable(struct pxa_udc *udc);
1467 static void udc_disable(struct pxa_udc *udc);
1468 
1469 /**
1470  * should_enable_udc - Tells if UDC should be enabled
1471  * @udc: udc device
1472  * Context: any
1473  *
1474  * The UDC should be enabled if :
1475  *  - the pullup resistor is connected
1476  *  - and a gadget driver is bound
1477  *  - and vbus is sensed (or no vbus sense is available)
1478  *
1479  * Returns 1 if UDC should be enabled, 0 otherwise
1480  */
1481 static int should_enable_udc(struct pxa_udc *udc)
1482 {
1483 	int put_on;
1484 
1485 	put_on = ((udc->pullup_on) && (udc->driver));
1486 	put_on &= ((udc->vbus_sensed) || (IS_ERR_OR_NULL(udc->transceiver)));
1487 	return put_on;
1488 }
1489 
1490 /**
1491  * should_disable_udc - Tells if UDC should be disabled
1492  * @udc: udc device
1493  * Context: any
1494  *
1495  * The UDC should be disabled if :
1496  *  - the pullup resistor is not connected
1497  *  - or no gadget driver is bound
1498  *  - or no vbus is sensed (when vbus sesing is available)
1499  *
1500  * Returns 1 if UDC should be disabled
1501  */
1502 static int should_disable_udc(struct pxa_udc *udc)
1503 {
1504 	int put_off;
1505 
1506 	put_off = ((!udc->pullup_on) || (!udc->driver));
1507 	put_off |= ((!udc->vbus_sensed) && (!IS_ERR_OR_NULL(udc->transceiver)));
1508 	return put_off;
1509 }
1510 
1511 /**
1512  * pxa_udc_pullup - Offer manual D+ pullup control
1513  * @_gadget: usb gadget using the control
1514  * @is_active: 0 if disconnect, else connect D+ pullup resistor
1515  *
1516  * Context: task context, might sleep
1517  *
1518  * Returns 0 if OK, -EOPNOTSUPP if udc driver doesn't handle D+ pullup
1519  */
1520 static int pxa_udc_pullup(struct usb_gadget *_gadget, int is_active)
1521 {
1522 	struct pxa_udc *udc = to_gadget_udc(_gadget);
1523 
1524 	if (!udc->gpiod && !udc->udc_command)
1525 		return -EOPNOTSUPP;
1526 
1527 	dplus_pullup(udc, is_active);
1528 
1529 	if (should_enable_udc(udc))
1530 		udc_enable(udc);
1531 	if (should_disable_udc(udc))
1532 		udc_disable(udc);
1533 	return 0;
1534 }
1535 
1536 /**
1537  * pxa_udc_vbus_session - Called by external transceiver to enable/disable udc
1538  * @_gadget: usb gadget
1539  * @is_active: 0 if should disable the udc, 1 if should enable
1540  *
1541  * Enables the udc, and optionnaly activates D+ pullup resistor. Or disables the
1542  * udc, and deactivates D+ pullup resistor.
1543  *
1544  * Returns 0
1545  */
1546 static int pxa_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
1547 {
1548 	struct pxa_udc *udc = to_gadget_udc(_gadget);
1549 
1550 	udc->vbus_sensed = is_active;
1551 	if (should_enable_udc(udc))
1552 		udc_enable(udc);
1553 	if (should_disable_udc(udc))
1554 		udc_disable(udc);
1555 
1556 	return 0;
1557 }
1558 
1559 /**
1560  * pxa_udc_vbus_draw - Called by gadget driver after SET_CONFIGURATION completed
1561  * @_gadget: usb gadget
1562  * @mA: current drawn
1563  *
1564  * Context: task context, might sleep
1565  *
1566  * Called after a configuration was chosen by a USB host, to inform how much
1567  * current can be drawn by the device from VBus line.
1568  *
1569  * Returns 0 or -EOPNOTSUPP if no transceiver is handling the udc
1570  */
1571 static int pxa_udc_vbus_draw(struct usb_gadget *_gadget, unsigned mA)
1572 {
1573 	struct pxa_udc *udc;
1574 
1575 	udc = to_gadget_udc(_gadget);
1576 	if (!IS_ERR_OR_NULL(udc->transceiver))
1577 		return usb_phy_set_power(udc->transceiver, mA);
1578 	return -EOPNOTSUPP;
1579 }
1580 
1581 /**
1582  * pxa_udc_phy_event - Called by phy upon VBus event
1583  * @nb: notifier block
1584  * @action: phy action, is vbus connect or disconnect
1585  * @data: the usb_gadget structure in pxa_udc
1586  *
1587  * Called by the USB Phy when a cable connect or disconnect is sensed.
1588  *
1589  * Returns 0
1590  */
1591 static int pxa_udc_phy_event(struct notifier_block *nb, unsigned long action,
1592 			     void *data)
1593 {
1594 	struct usb_gadget *gadget = data;
1595 
1596 	switch (action) {
1597 	case USB_EVENT_VBUS:
1598 		usb_gadget_vbus_connect(gadget);
1599 		return NOTIFY_OK;
1600 	case USB_EVENT_NONE:
1601 		usb_gadget_vbus_disconnect(gadget);
1602 		return NOTIFY_OK;
1603 	default:
1604 		return NOTIFY_DONE;
1605 	}
1606 }
1607 
1608 static struct notifier_block pxa27x_udc_phy = {
1609 	.notifier_call = pxa_udc_phy_event,
1610 };
1611 
1612 static int pxa27x_udc_start(struct usb_gadget *g,
1613 		struct usb_gadget_driver *driver);
1614 static int pxa27x_udc_stop(struct usb_gadget *g);
1615 
1616 static const struct usb_gadget_ops pxa_udc_ops = {
1617 	.get_frame	= pxa_udc_get_frame,
1618 	.wakeup		= pxa_udc_wakeup,
1619 	.pullup		= pxa_udc_pullup,
1620 	.vbus_session	= pxa_udc_vbus_session,
1621 	.vbus_draw	= pxa_udc_vbus_draw,
1622 	.udc_start	= pxa27x_udc_start,
1623 	.udc_stop	= pxa27x_udc_stop,
1624 };
1625 
1626 /**
1627  * udc_disable - disable udc device controller
1628  * @udc: udc device
1629  * Context: any
1630  *
1631  * Disables the udc device : disables clocks, udc interrupts, control endpoint
1632  * interrupts.
1633  */
1634 static void udc_disable(struct pxa_udc *udc)
1635 {
1636 	if (!udc->enabled)
1637 		return;
1638 
1639 	udc_writel(udc, UDCICR0, 0);
1640 	udc_writel(udc, UDCICR1, 0);
1641 
1642 	udc_clear_mask_UDCCR(udc, UDCCR_UDE);
1643 
1644 	ep0_idle(udc);
1645 	udc->gadget.speed = USB_SPEED_UNKNOWN;
1646 	clk_disable(udc->clk);
1647 
1648 	udc->enabled = 0;
1649 }
1650 
1651 /**
1652  * udc_init_data - Initialize udc device data structures
1653  * @dev: udc device
1654  *
1655  * Initializes gadget endpoint list, endpoints locks. No action is taken
1656  * on the hardware.
1657  */
1658 static void udc_init_data(struct pxa_udc *dev)
1659 {
1660 	int i;
1661 	struct pxa_ep *ep;
1662 
1663 	/* device/ep0 records init */
1664 	INIT_LIST_HEAD(&dev->gadget.ep_list);
1665 	INIT_LIST_HEAD(&dev->gadget.ep0->ep_list);
1666 	dev->udc_usb_ep[0].pxa_ep = &dev->pxa_ep[0];
1667 	dev->gadget.quirk_altset_not_supp = 1;
1668 	ep0_idle(dev);
1669 
1670 	/* PXA endpoints init */
1671 	for (i = 0; i < NR_PXA_ENDPOINTS; i++) {
1672 		ep = &dev->pxa_ep[i];
1673 
1674 		ep->enabled = is_ep0(ep);
1675 		INIT_LIST_HEAD(&ep->queue);
1676 		spin_lock_init(&ep->lock);
1677 	}
1678 
1679 	/* USB endpoints init */
1680 	for (i = 1; i < NR_USB_ENDPOINTS; i++) {
1681 		list_add_tail(&dev->udc_usb_ep[i].usb_ep.ep_list,
1682 				&dev->gadget.ep_list);
1683 		usb_ep_set_maxpacket_limit(&dev->udc_usb_ep[i].usb_ep,
1684 					   dev->udc_usb_ep[i].usb_ep.maxpacket);
1685 	}
1686 }
1687 
1688 /**
1689  * udc_enable - Enables the udc device
1690  * @udc: udc device
1691  *
1692  * Enables the udc device : enables clocks, udc interrupts, control endpoint
1693  * interrupts, sets usb as UDC client and setups endpoints.
1694  */
1695 static void udc_enable(struct pxa_udc *udc)
1696 {
1697 	if (udc->enabled)
1698 		return;
1699 
1700 	clk_enable(udc->clk);
1701 	udc_writel(udc, UDCICR0, 0);
1702 	udc_writel(udc, UDCICR1, 0);
1703 	udc_clear_mask_UDCCR(udc, UDCCR_UDE);
1704 
1705 	ep0_idle(udc);
1706 	udc->gadget.speed = USB_SPEED_FULL;
1707 	memset(&udc->stats, 0, sizeof(udc->stats));
1708 
1709 	pxa_eps_setup(udc);
1710 	udc_set_mask_UDCCR(udc, UDCCR_UDE);
1711 	ep_write_UDCCSR(&udc->pxa_ep[0], UDCCSR0_ACM);
1712 	udelay(2);
1713 	if (udc_readl(udc, UDCCR) & UDCCR_EMCE)
1714 		dev_err(udc->dev, "Configuration errors, udc disabled\n");
1715 
1716 	/*
1717 	 * Caller must be able to sleep in order to cope with startup transients
1718 	 */
1719 	msleep(100);
1720 
1721 	/* enable suspend/resume and reset irqs */
1722 	udc_writel(udc, UDCICR1,
1723 			UDCICR1_IECC | UDCICR1_IERU
1724 			| UDCICR1_IESU | UDCICR1_IERS);
1725 
1726 	/* enable ep0 irqs */
1727 	pio_irq_enable(&udc->pxa_ep[0]);
1728 
1729 	udc->enabled = 1;
1730 }
1731 
1732 /**
1733  * pxa27x_start - Register gadget driver
1734  * @g: gadget
1735  * @driver: gadget driver
1736  *
1737  * When a driver is successfully registered, it will receive control requests
1738  * including set_configuration(), which enables non-control requests.  Then
1739  * usb traffic follows until a disconnect is reported.  Then a host may connect
1740  * again, or the driver might get unbound.
1741  *
1742  * Note that the udc is not automatically enabled. Check function
1743  * should_enable_udc().
1744  *
1745  * Returns 0 if no error, -EINVAL, -ENODEV, -EBUSY otherwise
1746  */
1747 static int pxa27x_udc_start(struct usb_gadget *g,
1748 		struct usb_gadget_driver *driver)
1749 {
1750 	struct pxa_udc *udc = to_pxa(g);
1751 	int retval;
1752 
1753 	/* first hook up the driver ... */
1754 	udc->driver = driver;
1755 
1756 	if (!IS_ERR_OR_NULL(udc->transceiver)) {
1757 		retval = otg_set_peripheral(udc->transceiver->otg,
1758 						&udc->gadget);
1759 		if (retval) {
1760 			dev_err(udc->dev, "can't bind to transceiver\n");
1761 			goto fail;
1762 		}
1763 	}
1764 
1765 	if (should_enable_udc(udc))
1766 		udc_enable(udc);
1767 	return 0;
1768 
1769 fail:
1770 	udc->driver = NULL;
1771 	return retval;
1772 }
1773 
1774 /**
1775  * stop_activity - Stops udc endpoints
1776  * @udc: udc device
1777  *
1778  * Disables all udc endpoints (even control endpoint), report disconnect to
1779  * the gadget user.
1780  */
1781 static void stop_activity(struct pxa_udc *udc)
1782 {
1783 	int i;
1784 
1785 	udc->gadget.speed = USB_SPEED_UNKNOWN;
1786 
1787 	for (i = 0; i < NR_USB_ENDPOINTS; i++)
1788 		pxa_ep_disable(&udc->udc_usb_ep[i].usb_ep);
1789 }
1790 
1791 /**
1792  * pxa27x_udc_stop - Unregister the gadget driver
1793  * @g: gadget
1794  *
1795  * Returns 0 if no error, -ENODEV, -EINVAL otherwise
1796  */
1797 static int pxa27x_udc_stop(struct usb_gadget *g)
1798 {
1799 	struct pxa_udc *udc = to_pxa(g);
1800 
1801 	stop_activity(udc);
1802 	udc_disable(udc);
1803 
1804 	udc->driver = NULL;
1805 
1806 	if (!IS_ERR_OR_NULL(udc->transceiver))
1807 		return otg_set_peripheral(udc->transceiver->otg, NULL);
1808 	return 0;
1809 }
1810 
1811 /**
1812  * handle_ep0_ctrl_req - handle control endpoint control request
1813  * @udc: udc device
1814  * @req: control request
1815  */
1816 static void handle_ep0_ctrl_req(struct pxa_udc *udc,
1817 				struct pxa27x_request *req)
1818 {
1819 	struct pxa_ep *ep = &udc->pxa_ep[0];
1820 	union {
1821 		struct usb_ctrlrequest	r;
1822 		u32			word[2];
1823 	} u;
1824 	int i;
1825 	int have_extrabytes = 0;
1826 	unsigned long flags;
1827 
1828 	nuke(ep, -EPROTO);
1829 	spin_lock_irqsave(&ep->lock, flags);
1830 
1831 	/*
1832 	 * In the PXA320 manual, in the section about Back-to-Back setup
1833 	 * packets, it describes this situation.  The solution is to set OPC to
1834 	 * get rid of the status packet, and then continue with the setup
1835 	 * packet. Generalize to pxa27x CPUs.
1836 	 */
1837 	if (epout_has_pkt(ep) && (ep_count_bytes_remain(ep) == 0))
1838 		ep_write_UDCCSR(ep, UDCCSR0_OPC);
1839 
1840 	/* read SETUP packet */
1841 	for (i = 0; i < 2; i++) {
1842 		if (unlikely(ep_is_empty(ep)))
1843 			goto stall;
1844 		u.word[i] = udc_ep_readl(ep, UDCDR);
1845 	}
1846 
1847 	have_extrabytes = !ep_is_empty(ep);
1848 	while (!ep_is_empty(ep)) {
1849 		i = udc_ep_readl(ep, UDCDR);
1850 		ep_err(ep, "wrong to have extra bytes for setup : 0x%08x\n", i);
1851 	}
1852 
1853 	ep_dbg(ep, "SETUP %02x.%02x v%04x i%04x l%04x\n",
1854 		u.r.bRequestType, u.r.bRequest,
1855 		le16_to_cpu(u.r.wValue), le16_to_cpu(u.r.wIndex),
1856 		le16_to_cpu(u.r.wLength));
1857 	if (unlikely(have_extrabytes))
1858 		goto stall;
1859 
1860 	if (u.r.bRequestType & USB_DIR_IN)
1861 		set_ep0state(udc, IN_DATA_STAGE);
1862 	else
1863 		set_ep0state(udc, OUT_DATA_STAGE);
1864 
1865 	/* Tell UDC to enter Data Stage */
1866 	ep_write_UDCCSR(ep, UDCCSR0_SA | UDCCSR0_OPC);
1867 
1868 	spin_unlock_irqrestore(&ep->lock, flags);
1869 	i = udc->driver->setup(&udc->gadget, &u.r);
1870 	spin_lock_irqsave(&ep->lock, flags);
1871 	if (i < 0)
1872 		goto stall;
1873 out:
1874 	spin_unlock_irqrestore(&ep->lock, flags);
1875 	return;
1876 stall:
1877 	ep_dbg(ep, "protocol STALL, udccsr0=%03x err %d\n",
1878 		udc_ep_readl(ep, UDCCSR), i);
1879 	ep_write_UDCCSR(ep, UDCCSR0_FST | UDCCSR0_FTF);
1880 	set_ep0state(udc, STALL);
1881 	goto out;
1882 }
1883 
1884 /**
1885  * handle_ep0 - Handle control endpoint data transfers
1886  * @udc: udc device
1887  * @fifo_irq: 1 if triggered by fifo service type irq
1888  * @opc_irq: 1 if triggered by output packet complete type irq
1889  *
1890  * Context : interrupt handler
1891  *
1892  * Tries to transfer all pending request data into the endpoint and/or
1893  * transfer all pending data in the endpoint into usb requests.
1894  * Handles states of ep0 automata.
1895  *
1896  * PXA27x hardware handles several standard usb control requests without
1897  * driver notification.  The requests fully handled by hardware are :
1898  *  SET_ADDRESS, SET_FEATURE, CLEAR_FEATURE, GET_CONFIGURATION, GET_INTERFACE,
1899  *  GET_STATUS
1900  * The requests handled by hardware, but with irq notification are :
1901  *  SYNCH_FRAME, SET_CONFIGURATION, SET_INTERFACE
1902  * The remaining standard requests really handled by handle_ep0 are :
1903  *  GET_DESCRIPTOR, SET_DESCRIPTOR, specific requests.
1904  * Requests standardized outside of USB 2.0 chapter 9 are handled more
1905  * uniformly, by gadget drivers.
1906  *
1907  * The control endpoint state machine is _not_ USB spec compliant, it's even
1908  * hardly compliant with Intel PXA270 developers guide.
1909  * The key points which inferred this state machine are :
1910  *   - on every setup token, bit UDCCSR0_SA is raised and held until cleared by
1911  *     software.
1912  *   - on every OUT packet received, UDCCSR0_OPC is raised and held until
1913  *     cleared by software.
1914  *   - clearing UDCCSR0_OPC always flushes ep0. If in setup stage, never do it
1915  *     before reading ep0.
1916  *     This is true only for PXA27x. This is not true anymore for PXA3xx family
1917  *     (check Back-to-Back setup packet in developers guide).
1918  *   - irq can be called on a "packet complete" event (opc_irq=1), while
1919  *     UDCCSR0_OPC is not yet raised (delta can be as big as 100ms
1920  *     from experimentation).
1921  *   - as UDCCSR0_SA can be activated while in irq handling, and clearing
1922  *     UDCCSR0_OPC would flush the setup data, we almost never clear UDCCSR0_OPC
1923  *     => we never actually read the "status stage" packet of an IN data stage
1924  *     => this is not documented in Intel documentation
1925  *   - hardware as no idea of STATUS STAGE, it only handle SETUP STAGE and DATA
1926  *     STAGE. The driver add STATUS STAGE to send last zero length packet in
1927  *     OUT_STATUS_STAGE.
1928  *   - special attention was needed for IN_STATUS_STAGE. If a packet complete
1929  *     event is detected, we terminate the status stage without ackowledging the
1930  *     packet (not to risk to loose a potential SETUP packet)
1931  */
1932 static void handle_ep0(struct pxa_udc *udc, int fifo_irq, int opc_irq)
1933 {
1934 	u32			udccsr0;
1935 	struct pxa_ep		*ep = &udc->pxa_ep[0];
1936 	struct pxa27x_request	*req = NULL;
1937 	int			completed = 0;
1938 
1939 	if (!list_empty(&ep->queue))
1940 		req = list_entry(ep->queue.next, struct pxa27x_request, queue);
1941 
1942 	udccsr0 = udc_ep_readl(ep, UDCCSR);
1943 	ep_dbg(ep, "state=%s, req=%p, udccsr0=0x%03x, udcbcr=%d, irq_msk=%x\n",
1944 		EP0_STNAME(udc), req, udccsr0, udc_ep_readl(ep, UDCBCR),
1945 		(fifo_irq << 1 | opc_irq));
1946 
1947 	if (udccsr0 & UDCCSR0_SST) {
1948 		ep_dbg(ep, "clearing stall status\n");
1949 		nuke(ep, -EPIPE);
1950 		ep_write_UDCCSR(ep, UDCCSR0_SST);
1951 		ep0_idle(udc);
1952 	}
1953 
1954 	if (udccsr0 & UDCCSR0_SA) {
1955 		nuke(ep, 0);
1956 		set_ep0state(udc, SETUP_STAGE);
1957 	}
1958 
1959 	switch (udc->ep0state) {
1960 	case WAIT_FOR_SETUP:
1961 		/*
1962 		 * Hardware bug : beware, we cannot clear OPC, since we would
1963 		 * miss a potential OPC irq for a setup packet.
1964 		 * So, we only do ... nothing, and hope for a next irq with
1965 		 * UDCCSR0_SA set.
1966 		 */
1967 		break;
1968 	case SETUP_STAGE:
1969 		udccsr0 &= UDCCSR0_CTRL_REQ_MASK;
1970 		if (likely(udccsr0 == UDCCSR0_CTRL_REQ_MASK))
1971 			handle_ep0_ctrl_req(udc, req);
1972 		break;
1973 	case IN_DATA_STAGE:			/* GET_DESCRIPTOR */
1974 		if (epout_has_pkt(ep))
1975 			ep_write_UDCCSR(ep, UDCCSR0_OPC);
1976 		if (req && !ep_is_full(ep))
1977 			completed = write_ep0_fifo(ep, req);
1978 		if (completed)
1979 			ep0_end_in_req(ep, req, NULL);
1980 		break;
1981 	case OUT_DATA_STAGE:			/* SET_DESCRIPTOR */
1982 		if (epout_has_pkt(ep) && req)
1983 			completed = read_ep0_fifo(ep, req);
1984 		if (completed)
1985 			ep0_end_out_req(ep, req, NULL);
1986 		break;
1987 	case STALL:
1988 		ep_write_UDCCSR(ep, UDCCSR0_FST);
1989 		break;
1990 	case IN_STATUS_STAGE:
1991 		/*
1992 		 * Hardware bug : beware, we cannot clear OPC, since we would
1993 		 * miss a potential PC irq for a setup packet.
1994 		 * So, we only put the ep0 into WAIT_FOR_SETUP state.
1995 		 */
1996 		if (opc_irq)
1997 			ep0_idle(udc);
1998 		break;
1999 	case OUT_STATUS_STAGE:
2000 	case WAIT_ACK_SET_CONF_INTERF:
2001 		ep_warn(ep, "should never get in %s state here!!!\n",
2002 				EP0_STNAME(ep->dev));
2003 		ep0_idle(udc);
2004 		break;
2005 	}
2006 }
2007 
2008 /**
2009  * handle_ep - Handle endpoint data tranfers
2010  * @ep: pxa physical endpoint
2011  *
2012  * Tries to transfer all pending request data into the endpoint and/or
2013  * transfer all pending data in the endpoint into usb requests.
2014  *
2015  * Is always called from the interrupt handler. ep->lock must not be held.
2016  */
2017 static void handle_ep(struct pxa_ep *ep)
2018 {
2019 	struct pxa27x_request	*req;
2020 	int completed;
2021 	u32 udccsr;
2022 	int is_in = ep->dir_in;
2023 	int loop = 0;
2024 	unsigned long		flags;
2025 
2026 	spin_lock_irqsave(&ep->lock, flags);
2027 	if (ep->in_handle_ep)
2028 		goto recursion_detected;
2029 	ep->in_handle_ep = 1;
2030 
2031 	do {
2032 		completed = 0;
2033 		udccsr = udc_ep_readl(ep, UDCCSR);
2034 
2035 		if (likely(!list_empty(&ep->queue)))
2036 			req = list_entry(ep->queue.next,
2037 					struct pxa27x_request, queue);
2038 		else
2039 			req = NULL;
2040 
2041 		ep_dbg(ep, "req:%p, udccsr 0x%03x loop=%d\n",
2042 				req, udccsr, loop++);
2043 
2044 		if (unlikely(udccsr & (UDCCSR_SST | UDCCSR_TRN)))
2045 			udc_ep_writel(ep, UDCCSR,
2046 					udccsr & (UDCCSR_SST | UDCCSR_TRN));
2047 		if (!req)
2048 			break;
2049 
2050 		if (unlikely(is_in)) {
2051 			if (likely(!ep_is_full(ep)))
2052 				completed = write_fifo(ep, req);
2053 		} else {
2054 			if (likely(epout_has_pkt(ep)))
2055 				completed = read_fifo(ep, req);
2056 		}
2057 
2058 		if (completed) {
2059 			if (is_in)
2060 				ep_end_in_req(ep, req, &flags);
2061 			else
2062 				ep_end_out_req(ep, req, &flags);
2063 		}
2064 	} while (completed);
2065 
2066 	ep->in_handle_ep = 0;
2067 recursion_detected:
2068 	spin_unlock_irqrestore(&ep->lock, flags);
2069 }
2070 
2071 /**
2072  * pxa27x_change_configuration - Handle SET_CONF usb request notification
2073  * @udc: udc device
2074  * @config: usb configuration
2075  *
2076  * Post the request to upper level.
2077  * Don't use any pxa specific harware configuration capabilities
2078  */
2079 static void pxa27x_change_configuration(struct pxa_udc *udc, int config)
2080 {
2081 	struct usb_ctrlrequest req ;
2082 
2083 	dev_dbg(udc->dev, "config=%d\n", config);
2084 
2085 	udc->config = config;
2086 	udc->last_interface = 0;
2087 	udc->last_alternate = 0;
2088 
2089 	req.bRequestType = 0;
2090 	req.bRequest = USB_REQ_SET_CONFIGURATION;
2091 	req.wValue = config;
2092 	req.wIndex = 0;
2093 	req.wLength = 0;
2094 
2095 	set_ep0state(udc, WAIT_ACK_SET_CONF_INTERF);
2096 	udc->driver->setup(&udc->gadget, &req);
2097 	ep_write_UDCCSR(&udc->pxa_ep[0], UDCCSR0_AREN);
2098 }
2099 
2100 /**
2101  * pxa27x_change_interface - Handle SET_INTERF usb request notification
2102  * @udc: udc device
2103  * @iface: interface number
2104  * @alt: alternate setting number
2105  *
2106  * Post the request to upper level.
2107  * Don't use any pxa specific harware configuration capabilities
2108  */
2109 static void pxa27x_change_interface(struct pxa_udc *udc, int iface, int alt)
2110 {
2111 	struct usb_ctrlrequest  req;
2112 
2113 	dev_dbg(udc->dev, "interface=%d, alternate setting=%d\n", iface, alt);
2114 
2115 	udc->last_interface = iface;
2116 	udc->last_alternate = alt;
2117 
2118 	req.bRequestType = USB_RECIP_INTERFACE;
2119 	req.bRequest = USB_REQ_SET_INTERFACE;
2120 	req.wValue = alt;
2121 	req.wIndex = iface;
2122 	req.wLength = 0;
2123 
2124 	set_ep0state(udc, WAIT_ACK_SET_CONF_INTERF);
2125 	udc->driver->setup(&udc->gadget, &req);
2126 	ep_write_UDCCSR(&udc->pxa_ep[0], UDCCSR0_AREN);
2127 }
2128 
2129 /*
2130  * irq_handle_data - Handle data transfer
2131  * @irq: irq IRQ number
2132  * @udc: dev pxa_udc device structure
2133  *
2134  * Called from irq handler, transferts data to or from endpoint to queue
2135  */
2136 static void irq_handle_data(int irq, struct pxa_udc *udc)
2137 {
2138 	int i;
2139 	struct pxa_ep *ep;
2140 	u32 udcisr0 = udc_readl(udc, UDCISR0) & UDCCISR0_EP_MASK;
2141 	u32 udcisr1 = udc_readl(udc, UDCISR1) & UDCCISR1_EP_MASK;
2142 
2143 	if (udcisr0 & UDCISR_INT_MASK) {
2144 		udc->pxa_ep[0].stats.irqs++;
2145 		udc_writel(udc, UDCISR0, UDCISR_INT(0, UDCISR_INT_MASK));
2146 		handle_ep0(udc, !!(udcisr0 & UDCICR_FIFOERR),
2147 				!!(udcisr0 & UDCICR_PKTCOMPL));
2148 	}
2149 
2150 	udcisr0 >>= 2;
2151 	for (i = 1; udcisr0 != 0 && i < 16; udcisr0 >>= 2, i++) {
2152 		if (!(udcisr0 & UDCISR_INT_MASK))
2153 			continue;
2154 
2155 		udc_writel(udc, UDCISR0, UDCISR_INT(i, UDCISR_INT_MASK));
2156 
2157 		WARN_ON(i >= ARRAY_SIZE(udc->pxa_ep));
2158 		if (i < ARRAY_SIZE(udc->pxa_ep)) {
2159 			ep = &udc->pxa_ep[i];
2160 			ep->stats.irqs++;
2161 			handle_ep(ep);
2162 		}
2163 	}
2164 
2165 	for (i = 16; udcisr1 != 0 && i < 24; udcisr1 >>= 2, i++) {
2166 		udc_writel(udc, UDCISR1, UDCISR_INT(i - 16, UDCISR_INT_MASK));
2167 		if (!(udcisr1 & UDCISR_INT_MASK))
2168 			continue;
2169 
2170 		WARN_ON(i >= ARRAY_SIZE(udc->pxa_ep));
2171 		if (i < ARRAY_SIZE(udc->pxa_ep)) {
2172 			ep = &udc->pxa_ep[i];
2173 			ep->stats.irqs++;
2174 			handle_ep(ep);
2175 		}
2176 	}
2177 
2178 }
2179 
2180 /**
2181  * irq_udc_suspend - Handle IRQ "UDC Suspend"
2182  * @udc: udc device
2183  */
2184 static void irq_udc_suspend(struct pxa_udc *udc)
2185 {
2186 	udc_writel(udc, UDCISR1, UDCISR1_IRSU);
2187 	udc->stats.irqs_suspend++;
2188 
2189 	if (udc->gadget.speed != USB_SPEED_UNKNOWN
2190 			&& udc->driver && udc->driver->suspend)
2191 		udc->driver->suspend(&udc->gadget);
2192 	ep0_idle(udc);
2193 }
2194 
2195 /**
2196   * irq_udc_resume - Handle IRQ "UDC Resume"
2197   * @udc: udc device
2198   */
2199 static void irq_udc_resume(struct pxa_udc *udc)
2200 {
2201 	udc_writel(udc, UDCISR1, UDCISR1_IRRU);
2202 	udc->stats.irqs_resume++;
2203 
2204 	if (udc->gadget.speed != USB_SPEED_UNKNOWN
2205 			&& udc->driver && udc->driver->resume)
2206 		udc->driver->resume(&udc->gadget);
2207 }
2208 
2209 /**
2210  * irq_udc_reconfig - Handle IRQ "UDC Change Configuration"
2211  * @udc: udc device
2212  */
2213 static void irq_udc_reconfig(struct pxa_udc *udc)
2214 {
2215 	unsigned config, interface, alternate, config_change;
2216 	u32 udccr = udc_readl(udc, UDCCR);
2217 
2218 	udc_writel(udc, UDCISR1, UDCISR1_IRCC);
2219 	udc->stats.irqs_reconfig++;
2220 
2221 	config = (udccr & UDCCR_ACN) >> UDCCR_ACN_S;
2222 	config_change = (config != udc->config);
2223 	pxa27x_change_configuration(udc, config);
2224 
2225 	interface = (udccr & UDCCR_AIN) >> UDCCR_AIN_S;
2226 	alternate = (udccr & UDCCR_AAISN) >> UDCCR_AAISN_S;
2227 	pxa27x_change_interface(udc, interface, alternate);
2228 
2229 	if (config_change)
2230 		update_pxa_ep_matches(udc);
2231 	udc_set_mask_UDCCR(udc, UDCCR_SMAC);
2232 }
2233 
2234 /**
2235  * irq_udc_reset - Handle IRQ "UDC Reset"
2236  * @udc: udc device
2237  */
2238 static void irq_udc_reset(struct pxa_udc *udc)
2239 {
2240 	u32 udccr = udc_readl(udc, UDCCR);
2241 	struct pxa_ep *ep = &udc->pxa_ep[0];
2242 
2243 	dev_info(udc->dev, "USB reset\n");
2244 	udc_writel(udc, UDCISR1, UDCISR1_IRRS);
2245 	udc->stats.irqs_reset++;
2246 
2247 	if ((udccr & UDCCR_UDA) == 0) {
2248 		dev_dbg(udc->dev, "USB reset start\n");
2249 		stop_activity(udc);
2250 	}
2251 	udc->gadget.speed = USB_SPEED_FULL;
2252 	memset(&udc->stats, 0, sizeof udc->stats);
2253 
2254 	nuke(ep, -EPROTO);
2255 	ep_write_UDCCSR(ep, UDCCSR0_FTF | UDCCSR0_OPC);
2256 	ep0_idle(udc);
2257 }
2258 
2259 /**
2260  * pxa_udc_irq - Main irq handler
2261  * @irq: irq number
2262  * @_dev: udc device
2263  *
2264  * Handles all udc interrupts
2265  */
2266 static irqreturn_t pxa_udc_irq(int irq, void *_dev)
2267 {
2268 	struct pxa_udc *udc = _dev;
2269 	u32 udcisr0 = udc_readl(udc, UDCISR0);
2270 	u32 udcisr1 = udc_readl(udc, UDCISR1);
2271 	u32 udccr = udc_readl(udc, UDCCR);
2272 	u32 udcisr1_spec;
2273 
2274 	dev_vdbg(udc->dev, "Interrupt, UDCISR0:0x%08x, UDCISR1:0x%08x, "
2275 		 "UDCCR:0x%08x\n", udcisr0, udcisr1, udccr);
2276 
2277 	udcisr1_spec = udcisr1 & 0xf8000000;
2278 	if (unlikely(udcisr1_spec & UDCISR1_IRSU))
2279 		irq_udc_suspend(udc);
2280 	if (unlikely(udcisr1_spec & UDCISR1_IRRU))
2281 		irq_udc_resume(udc);
2282 	if (unlikely(udcisr1_spec & UDCISR1_IRCC))
2283 		irq_udc_reconfig(udc);
2284 	if (unlikely(udcisr1_spec & UDCISR1_IRRS))
2285 		irq_udc_reset(udc);
2286 
2287 	if ((udcisr0 & UDCCISR0_EP_MASK) | (udcisr1 & UDCCISR1_EP_MASK))
2288 		irq_handle_data(irq, udc);
2289 
2290 	return IRQ_HANDLED;
2291 }
2292 
2293 static struct pxa_udc memory = {
2294 	.gadget = {
2295 		.ops		= &pxa_udc_ops,
2296 		.ep0		= &memory.udc_usb_ep[0].usb_ep,
2297 		.name		= driver_name,
2298 		.dev = {
2299 			.init_name	= "gadget",
2300 		},
2301 	},
2302 
2303 	.udc_usb_ep = {
2304 		USB_EP_CTRL,
2305 		USB_EP_OUT_BULK(1),
2306 		USB_EP_IN_BULK(2),
2307 		USB_EP_IN_ISO(3),
2308 		USB_EP_OUT_ISO(4),
2309 		USB_EP_IN_INT(5),
2310 	},
2311 
2312 	.pxa_ep = {
2313 		PXA_EP_CTRL,
2314 		/* Endpoints for gadget zero */
2315 		PXA_EP_OUT_BULK(1, 1, 3, 0, 0),
2316 		PXA_EP_IN_BULK(2,  2, 3, 0, 0),
2317 		/* Endpoints for ether gadget, file storage gadget */
2318 		PXA_EP_OUT_BULK(3, 1, 1, 0, 0),
2319 		PXA_EP_IN_BULK(4,  2, 1, 0, 0),
2320 		PXA_EP_IN_ISO(5,   3, 1, 0, 0),
2321 		PXA_EP_OUT_ISO(6,  4, 1, 0, 0),
2322 		PXA_EP_IN_INT(7,   5, 1, 0, 0),
2323 		/* Endpoints for RNDIS, serial */
2324 		PXA_EP_OUT_BULK(8, 1, 2, 0, 0),
2325 		PXA_EP_IN_BULK(9,  2, 2, 0, 0),
2326 		PXA_EP_IN_INT(10,  5, 2, 0, 0),
2327 		/*
2328 		 * All the following endpoints are only for completion.  They
2329 		 * won't never work, as multiple interfaces are really broken on
2330 		 * the pxa.
2331 		*/
2332 		PXA_EP_OUT_BULK(11, 1, 2, 1, 0),
2333 		PXA_EP_IN_BULK(12,  2, 2, 1, 0),
2334 		/* Endpoint for CDC Ether */
2335 		PXA_EP_OUT_BULK(13, 1, 1, 1, 1),
2336 		PXA_EP_IN_BULK(14,  2, 1, 1, 1),
2337 	}
2338 };
2339 
2340 #if defined(CONFIG_OF)
2341 static const struct of_device_id udc_pxa_dt_ids[] = {
2342 	{ .compatible = "marvell,pxa270-udc" },
2343 	{}
2344 };
2345 MODULE_DEVICE_TABLE(of, udc_pxa_dt_ids);
2346 #endif
2347 
2348 /**
2349  * pxa_udc_probe - probes the udc device
2350  * @pdev: platform device
2351  *
2352  * Perform basic init : allocates udc clock, creates sysfs files, requests
2353  * irq.
2354  */
2355 static int pxa_udc_probe(struct platform_device *pdev)
2356 {
2357 	struct pxa_udc *udc = &memory;
2358 	int retval = 0, gpio;
2359 	struct pxa2xx_udc_mach_info *mach = dev_get_platdata(&pdev->dev);
2360 	unsigned long gpio_flags;
2361 
2362 	if (mach) {
2363 		gpio_flags = mach->gpio_pullup_inverted ? GPIOF_ACTIVE_LOW : 0;
2364 		gpio = mach->gpio_pullup;
2365 		if (gpio_is_valid(gpio)) {
2366 			retval = devm_gpio_request_one(&pdev->dev, gpio,
2367 						       gpio_flags,
2368 						       "USB D+ pullup");
2369 			if (retval)
2370 				return retval;
2371 			udc->gpiod = gpio_to_desc(mach->gpio_pullup);
2372 		}
2373 		udc->udc_command = mach->udc_command;
2374 	} else {
2375 		udc->gpiod = devm_gpiod_get(&pdev->dev, NULL, GPIOD_ASIS);
2376 	}
2377 
2378 	udc->regs = devm_platform_ioremap_resource(pdev, 0);
2379 	if (IS_ERR(udc->regs))
2380 		return PTR_ERR(udc->regs);
2381 	udc->irq = platform_get_irq(pdev, 0);
2382 	if (udc->irq < 0)
2383 		return udc->irq;
2384 
2385 	udc->dev = &pdev->dev;
2386 	if (of_have_populated_dt()) {
2387 		udc->transceiver =
2388 			devm_usb_get_phy_by_phandle(udc->dev, "phys", 0);
2389 		if (IS_ERR(udc->transceiver))
2390 			return PTR_ERR(udc->transceiver);
2391 	} else {
2392 		udc->transceiver = usb_get_phy(USB_PHY_TYPE_USB2);
2393 	}
2394 
2395 	if (IS_ERR(udc->gpiod)) {
2396 		dev_err(&pdev->dev, "Couldn't find or request D+ gpio : %ld\n",
2397 			PTR_ERR(udc->gpiod));
2398 		return PTR_ERR(udc->gpiod);
2399 	}
2400 	if (udc->gpiod)
2401 		gpiod_direction_output(udc->gpiod, 0);
2402 
2403 	udc->clk = devm_clk_get(&pdev->dev, NULL);
2404 	if (IS_ERR(udc->clk))
2405 		return PTR_ERR(udc->clk);
2406 
2407 	retval = clk_prepare(udc->clk);
2408 	if (retval)
2409 		return retval;
2410 
2411 	udc->vbus_sensed = 0;
2412 
2413 	the_controller = udc;
2414 	platform_set_drvdata(pdev, udc);
2415 	udc_init_data(udc);
2416 
2417 	/* irq setup after old hardware state is cleaned up */
2418 	retval = devm_request_irq(&pdev->dev, udc->irq, pxa_udc_irq,
2419 				  IRQF_SHARED, driver_name, udc);
2420 	if (retval != 0) {
2421 		dev_err(udc->dev, "%s: can't get irq %i, err %d\n",
2422 			driver_name, udc->irq, retval);
2423 		goto err;
2424 	}
2425 
2426 	if (!IS_ERR_OR_NULL(udc->transceiver))
2427 		usb_register_notifier(udc->transceiver, &pxa27x_udc_phy);
2428 	retval = usb_add_gadget_udc(&pdev->dev, &udc->gadget);
2429 	if (retval)
2430 		goto err_add_gadget;
2431 
2432 	pxa_init_debugfs(udc);
2433 	if (should_enable_udc(udc))
2434 		udc_enable(udc);
2435 	return 0;
2436 
2437 err_add_gadget:
2438 	if (!IS_ERR_OR_NULL(udc->transceiver))
2439 		usb_unregister_notifier(udc->transceiver, &pxa27x_udc_phy);
2440 err:
2441 	clk_unprepare(udc->clk);
2442 	return retval;
2443 }
2444 
2445 /**
2446  * pxa_udc_remove - removes the udc device driver
2447  * @_dev: platform device
2448  */
2449 static int pxa_udc_remove(struct platform_device *_dev)
2450 {
2451 	struct pxa_udc *udc = platform_get_drvdata(_dev);
2452 
2453 	usb_del_gadget_udc(&udc->gadget);
2454 	pxa_cleanup_debugfs(udc);
2455 
2456 	if (!IS_ERR_OR_NULL(udc->transceiver)) {
2457 		usb_unregister_notifier(udc->transceiver, &pxa27x_udc_phy);
2458 		usb_put_phy(udc->transceiver);
2459 	}
2460 
2461 	udc->transceiver = NULL;
2462 	the_controller = NULL;
2463 	clk_unprepare(udc->clk);
2464 
2465 	return 0;
2466 }
2467 
2468 static void pxa_udc_shutdown(struct platform_device *_dev)
2469 {
2470 	struct pxa_udc *udc = platform_get_drvdata(_dev);
2471 
2472 	if (udc_readl(udc, UDCCR) & UDCCR_UDE)
2473 		udc_disable(udc);
2474 }
2475 
2476 #ifdef CONFIG_PXA27x
2477 extern void pxa27x_clear_otgph(void);
2478 #else
2479 #define pxa27x_clear_otgph()   do {} while (0)
2480 #endif
2481 
2482 #ifdef CONFIG_PM
2483 /**
2484  * pxa_udc_suspend - Suspend udc device
2485  * @_dev: platform device
2486  * @state: suspend state
2487  *
2488  * Suspends udc : saves configuration registers (UDCCR*), then disables the udc
2489  * device.
2490  */
2491 static int pxa_udc_suspend(struct platform_device *_dev, pm_message_t state)
2492 {
2493 	struct pxa_udc *udc = platform_get_drvdata(_dev);
2494 	struct pxa_ep *ep;
2495 
2496 	ep = &udc->pxa_ep[0];
2497 	udc->udccsr0 = udc_ep_readl(ep, UDCCSR);
2498 
2499 	udc_disable(udc);
2500 	udc->pullup_resume = udc->pullup_on;
2501 	dplus_pullup(udc, 0);
2502 
2503 	if (udc->driver)
2504 		udc->driver->disconnect(&udc->gadget);
2505 
2506 	return 0;
2507 }
2508 
2509 /**
2510  * pxa_udc_resume - Resume udc device
2511  * @_dev: platform device
2512  *
2513  * Resumes udc : restores configuration registers (UDCCR*), then enables the udc
2514  * device.
2515  */
2516 static int pxa_udc_resume(struct platform_device *_dev)
2517 {
2518 	struct pxa_udc *udc = platform_get_drvdata(_dev);
2519 	struct pxa_ep *ep;
2520 
2521 	ep = &udc->pxa_ep[0];
2522 	udc_ep_writel(ep, UDCCSR, udc->udccsr0 & (UDCCSR0_FST | UDCCSR0_DME));
2523 
2524 	dplus_pullup(udc, udc->pullup_resume);
2525 	if (should_enable_udc(udc))
2526 		udc_enable(udc);
2527 	/*
2528 	 * We do not handle OTG yet.
2529 	 *
2530 	 * OTGPH bit is set when sleep mode is entered.
2531 	 * it indicates that OTG pad is retaining its state.
2532 	 * Upon exit from sleep mode and before clearing OTGPH,
2533 	 * Software must configure the USB OTG pad, UDC, and UHC
2534 	 * to the state they were in before entering sleep mode.
2535 	 */
2536 	pxa27x_clear_otgph();
2537 
2538 	return 0;
2539 }
2540 #endif
2541 
2542 /* work with hotplug and coldplug */
2543 MODULE_ALIAS("platform:pxa27x-udc");
2544 
2545 static struct platform_driver udc_driver = {
2546 	.driver		= {
2547 		.name	= "pxa27x-udc",
2548 		.of_match_table = of_match_ptr(udc_pxa_dt_ids),
2549 	},
2550 	.probe		= pxa_udc_probe,
2551 	.remove		= pxa_udc_remove,
2552 	.shutdown	= pxa_udc_shutdown,
2553 #ifdef CONFIG_PM
2554 	.suspend	= pxa_udc_suspend,
2555 	.resume		= pxa_udc_resume
2556 #endif
2557 };
2558 
2559 module_platform_driver(udc_driver);
2560 
2561 MODULE_DESCRIPTION(DRIVER_DESC);
2562 MODULE_AUTHOR("Robert Jarzmik");
2563 MODULE_LICENSE("GPL");
2564