1 /*
2 * Driver for the Diolan DLN-2 USB adapter
3 *
4 * Copyright (c) 2014 Intel Corporation
5 *
6 * Derived from:
7 * i2c-diolan-u2c.c
8 * Copyright (c) 2010-2011 Ericsson AB
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License as
12 * published by the Free Software Foundation, version 2.
13 */
14
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/types.h>
18 #include <linux/slab.h>
19 #include <linux/usb.h>
20 #include <linux/i2c.h>
21 #include <linux/mutex.h>
22 #include <linux/platform_device.h>
23 #include <linux/mfd/core.h>
24 #include <linux/mfd/dln2.h>
25 #include <linux/rculist.h>
26
27 struct dln2_header {
28 __le16 size;
29 __le16 id;
30 __le16 echo;
31 __le16 handle;
32 };
33
34 struct dln2_response {
35 struct dln2_header hdr;
36 __le16 result;
37 };
38
39 #define DLN2_GENERIC_MODULE_ID 0x00
40 #define DLN2_GENERIC_CMD(cmd) DLN2_CMD(cmd, DLN2_GENERIC_MODULE_ID)
41 #define CMD_GET_DEVICE_VER DLN2_GENERIC_CMD(0x30)
42 #define CMD_GET_DEVICE_SN DLN2_GENERIC_CMD(0x31)
43
44 #define DLN2_HW_ID 0x200
45 #define DLN2_USB_TIMEOUT 200 /* in ms */
46 #define DLN2_MAX_RX_SLOTS 16
47 #define DLN2_MAX_URBS 16
48 #define DLN2_RX_BUF_SIZE 512
49
50 enum dln2_handle {
51 DLN2_HANDLE_EVENT = 0, /* don't change, hardware defined */
52 DLN2_HANDLE_CTRL,
53 DLN2_HANDLE_GPIO,
54 DLN2_HANDLE_I2C,
55 DLN2_HANDLE_SPI,
56 DLN2_HANDLES
57 };
58
59 /*
60 * Receive context used between the receive demultiplexer and the transfer
61 * routine. While sending a request the transfer routine will look for a free
62 * receive context and use it to wait for a response and to receive the URB and
63 * thus the response data.
64 */
65 struct dln2_rx_context {
66 /* completion used to wait for a response */
67 struct completion done;
68
69 /* if non-NULL the URB contains the response */
70 struct urb *urb;
71
72 /* if true then this context is used to wait for a response */
73 bool in_use;
74 };
75
76 /*
77 * Receive contexts for a particular DLN2 module (i2c, gpio, etc.). We use the
78 * handle header field to identify the module in dln2_dev.mod_rx_slots and then
79 * the echo header field to index the slots field and find the receive context
80 * for a particular request.
81 */
82 struct dln2_mod_rx_slots {
83 /* RX slots bitmap */
84 DECLARE_BITMAP(bmap, DLN2_MAX_RX_SLOTS);
85
86 /* used to wait for a free RX slot */
87 wait_queue_head_t wq;
88
89 /* used to wait for an RX operation to complete */
90 struct dln2_rx_context slots[DLN2_MAX_RX_SLOTS];
91
92 /* avoid races between alloc/free_rx_slot and dln2_rx_transfer */
93 spinlock_t lock;
94 };
95
96 enum dln2_endpoint {
97 DLN2_EP_OUT = 0,
98 DLN2_EP_IN = 1,
99 };
100
101 struct dln2_dev {
102 struct usb_device *usb_dev;
103 struct usb_interface *interface;
104 u8 ep_in;
105 u8 ep_out;
106
107 struct urb *rx_urb[DLN2_MAX_URBS];
108 void *rx_buf[DLN2_MAX_URBS];
109
110 struct dln2_mod_rx_slots mod_rx_slots[DLN2_HANDLES];
111
112 struct list_head event_cb_list;
113 spinlock_t event_cb_lock;
114
115 bool disconnect;
116 int active_transfers;
117 wait_queue_head_t disconnect_wq;
118 spinlock_t disconnect_lock;
119 };
120
121 struct dln2_event_cb_entry {
122 struct list_head list;
123 u16 id;
124 struct platform_device *pdev;
125 dln2_event_cb_t callback;
126 };
127
dln2_register_event_cb(struct platform_device * pdev,u16 id,dln2_event_cb_t event_cb)128 int dln2_register_event_cb(struct platform_device *pdev, u16 id,
129 dln2_event_cb_t event_cb)
130 {
131 struct dln2_dev *dln2 = dev_get_drvdata(pdev->dev.parent);
132 struct dln2_event_cb_entry *i, *entry;
133 unsigned long flags;
134 int ret = 0;
135
136 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
137 if (!entry)
138 return -ENOMEM;
139
140 entry->id = id;
141 entry->callback = event_cb;
142 entry->pdev = pdev;
143
144 spin_lock_irqsave(&dln2->event_cb_lock, flags);
145
146 list_for_each_entry(i, &dln2->event_cb_list, list) {
147 if (i->id == id) {
148 ret = -EBUSY;
149 break;
150 }
151 }
152
153 if (!ret)
154 list_add_rcu(&entry->list, &dln2->event_cb_list);
155
156 spin_unlock_irqrestore(&dln2->event_cb_lock, flags);
157
158 if (ret)
159 kfree(entry);
160
161 return ret;
162 }
163 EXPORT_SYMBOL(dln2_register_event_cb);
164
dln2_unregister_event_cb(struct platform_device * pdev,u16 id)165 void dln2_unregister_event_cb(struct platform_device *pdev, u16 id)
166 {
167 struct dln2_dev *dln2 = dev_get_drvdata(pdev->dev.parent);
168 struct dln2_event_cb_entry *i;
169 unsigned long flags;
170 bool found = false;
171
172 spin_lock_irqsave(&dln2->event_cb_lock, flags);
173
174 list_for_each_entry(i, &dln2->event_cb_list, list) {
175 if (i->id == id) {
176 list_del_rcu(&i->list);
177 found = true;
178 break;
179 }
180 }
181
182 spin_unlock_irqrestore(&dln2->event_cb_lock, flags);
183
184 if (found) {
185 synchronize_rcu();
186 kfree(i);
187 }
188 }
189 EXPORT_SYMBOL(dln2_unregister_event_cb);
190
191 /*
192 * Returns true if a valid transfer slot is found. In this case the URB must not
193 * be resubmitted immediately in dln2_rx as we need the data when dln2_transfer
194 * is woke up. It will be resubmitted there.
195 */
dln2_transfer_complete(struct dln2_dev * dln2,struct urb * urb,u16 handle,u16 rx_slot)196 static bool dln2_transfer_complete(struct dln2_dev *dln2, struct urb *urb,
197 u16 handle, u16 rx_slot)
198 {
199 struct device *dev = &dln2->interface->dev;
200 struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle];
201 struct dln2_rx_context *rxc;
202 bool valid_slot = false;
203
204 if (rx_slot >= DLN2_MAX_RX_SLOTS)
205 goto out;
206
207 rxc = &rxs->slots[rx_slot];
208
209 /*
210 * No need to disable interrupts as this lock is not taken in interrupt
211 * context elsewhere in this driver. This function (or its callers) are
212 * also not exported to other modules.
213 */
214 spin_lock(&rxs->lock);
215 if (rxc->in_use && !rxc->urb) {
216 rxc->urb = urb;
217 complete(&rxc->done);
218 valid_slot = true;
219 }
220 spin_unlock(&rxs->lock);
221
222 out:
223 if (!valid_slot)
224 dev_warn(dev, "bad/late response %d/%d\n", handle, rx_slot);
225
226 return valid_slot;
227 }
228
dln2_run_event_callbacks(struct dln2_dev * dln2,u16 id,u16 echo,void * data,int len)229 static void dln2_run_event_callbacks(struct dln2_dev *dln2, u16 id, u16 echo,
230 void *data, int len)
231 {
232 struct dln2_event_cb_entry *i;
233
234 rcu_read_lock();
235
236 list_for_each_entry_rcu(i, &dln2->event_cb_list, list) {
237 if (i->id == id) {
238 i->callback(i->pdev, echo, data, len);
239 break;
240 }
241 }
242
243 rcu_read_unlock();
244 }
245
dln2_rx(struct urb * urb)246 static void dln2_rx(struct urb *urb)
247 {
248 struct dln2_dev *dln2 = urb->context;
249 struct dln2_header *hdr = urb->transfer_buffer;
250 struct device *dev = &dln2->interface->dev;
251 u16 id, echo, handle, size;
252 u8 *data;
253 int len;
254 int err;
255
256 switch (urb->status) {
257 case 0:
258 /* success */
259 break;
260 case -ECONNRESET:
261 case -ENOENT:
262 case -ESHUTDOWN:
263 case -EPIPE:
264 /* this urb is terminated, clean up */
265 dev_dbg(dev, "urb shutting down with status %d\n", urb->status);
266 return;
267 default:
268 dev_dbg(dev, "nonzero urb status received %d\n", urb->status);
269 goto out;
270 }
271
272 if (urb->actual_length < sizeof(struct dln2_header)) {
273 dev_err(dev, "short response: %d\n", urb->actual_length);
274 goto out;
275 }
276
277 handle = le16_to_cpu(hdr->handle);
278 id = le16_to_cpu(hdr->id);
279 echo = le16_to_cpu(hdr->echo);
280 size = le16_to_cpu(hdr->size);
281
282 if (size != urb->actual_length) {
283 dev_err(dev, "size mismatch: handle %x cmd %x echo %x size %d actual %d\n",
284 handle, id, echo, size, urb->actual_length);
285 goto out;
286 }
287
288 if (handle >= DLN2_HANDLES) {
289 dev_warn(dev, "invalid handle %d\n", handle);
290 goto out;
291 }
292
293 data = urb->transfer_buffer + sizeof(struct dln2_header);
294 len = urb->actual_length - sizeof(struct dln2_header);
295
296 if (handle == DLN2_HANDLE_EVENT) {
297 unsigned long flags;
298
299 spin_lock_irqsave(&dln2->event_cb_lock, flags);
300 dln2_run_event_callbacks(dln2, id, echo, data, len);
301 spin_unlock_irqrestore(&dln2->event_cb_lock, flags);
302 } else {
303 /* URB will be re-submitted in _dln2_transfer (free_rx_slot) */
304 if (dln2_transfer_complete(dln2, urb, handle, echo))
305 return;
306 }
307
308 out:
309 err = usb_submit_urb(urb, GFP_ATOMIC);
310 if (err < 0)
311 dev_err(dev, "failed to resubmit RX URB: %d\n", err);
312 }
313
dln2_prep_buf(u16 handle,u16 cmd,u16 echo,const void * obuf,int * obuf_len,gfp_t gfp)314 static void *dln2_prep_buf(u16 handle, u16 cmd, u16 echo, const void *obuf,
315 int *obuf_len, gfp_t gfp)
316 {
317 int len;
318 void *buf;
319 struct dln2_header *hdr;
320
321 len = *obuf_len + sizeof(*hdr);
322 buf = kmalloc(len, gfp);
323 if (!buf)
324 return NULL;
325
326 hdr = (struct dln2_header *)buf;
327 hdr->id = cpu_to_le16(cmd);
328 hdr->size = cpu_to_le16(len);
329 hdr->echo = cpu_to_le16(echo);
330 hdr->handle = cpu_to_le16(handle);
331
332 memcpy(buf + sizeof(*hdr), obuf, *obuf_len);
333
334 *obuf_len = len;
335
336 return buf;
337 }
338
dln2_send_wait(struct dln2_dev * dln2,u16 handle,u16 cmd,u16 echo,const void * obuf,int obuf_len)339 static int dln2_send_wait(struct dln2_dev *dln2, u16 handle, u16 cmd, u16 echo,
340 const void *obuf, int obuf_len)
341 {
342 int ret = 0;
343 int len = obuf_len;
344 void *buf;
345 int actual;
346
347 buf = dln2_prep_buf(handle, cmd, echo, obuf, &len, GFP_KERNEL);
348 if (!buf)
349 return -ENOMEM;
350
351 ret = usb_bulk_msg(dln2->usb_dev,
352 usb_sndbulkpipe(dln2->usb_dev, dln2->ep_out),
353 buf, len, &actual, DLN2_USB_TIMEOUT);
354
355 kfree(buf);
356
357 return ret;
358 }
359
find_free_slot(struct dln2_dev * dln2,u16 handle,int * slot)360 static bool find_free_slot(struct dln2_dev *dln2, u16 handle, int *slot)
361 {
362 struct dln2_mod_rx_slots *rxs;
363 unsigned long flags;
364
365 if (dln2->disconnect) {
366 *slot = -ENODEV;
367 return true;
368 }
369
370 rxs = &dln2->mod_rx_slots[handle];
371
372 spin_lock_irqsave(&rxs->lock, flags);
373
374 *slot = find_first_zero_bit(rxs->bmap, DLN2_MAX_RX_SLOTS);
375
376 if (*slot < DLN2_MAX_RX_SLOTS) {
377 struct dln2_rx_context *rxc = &rxs->slots[*slot];
378
379 set_bit(*slot, rxs->bmap);
380 rxc->in_use = true;
381 }
382
383 spin_unlock_irqrestore(&rxs->lock, flags);
384
385 return *slot < DLN2_MAX_RX_SLOTS;
386 }
387
alloc_rx_slot(struct dln2_dev * dln2,u16 handle)388 static int alloc_rx_slot(struct dln2_dev *dln2, u16 handle)
389 {
390 int ret;
391 int slot;
392
393 /*
394 * No need to timeout here, the wait is bounded by the timeout in
395 * _dln2_transfer.
396 */
397 ret = wait_event_interruptible(dln2->mod_rx_slots[handle].wq,
398 find_free_slot(dln2, handle, &slot));
399 if (ret < 0)
400 return ret;
401
402 return slot;
403 }
404
free_rx_slot(struct dln2_dev * dln2,u16 handle,int slot)405 static void free_rx_slot(struct dln2_dev *dln2, u16 handle, int slot)
406 {
407 struct dln2_mod_rx_slots *rxs;
408 struct urb *urb = NULL;
409 unsigned long flags;
410 struct dln2_rx_context *rxc;
411
412 rxs = &dln2->mod_rx_slots[handle];
413
414 spin_lock_irqsave(&rxs->lock, flags);
415
416 clear_bit(slot, rxs->bmap);
417
418 rxc = &rxs->slots[slot];
419 rxc->in_use = false;
420 urb = rxc->urb;
421 rxc->urb = NULL;
422 reinit_completion(&rxc->done);
423
424 spin_unlock_irqrestore(&rxs->lock, flags);
425
426 if (urb) {
427 int err;
428 struct device *dev = &dln2->interface->dev;
429
430 err = usb_submit_urb(urb, GFP_KERNEL);
431 if (err < 0)
432 dev_err(dev, "failed to resubmit RX URB: %d\n", err);
433 }
434
435 wake_up_interruptible(&rxs->wq);
436 }
437
_dln2_transfer(struct dln2_dev * dln2,u16 handle,u16 cmd,const void * obuf,unsigned obuf_len,void * ibuf,unsigned * ibuf_len)438 static int _dln2_transfer(struct dln2_dev *dln2, u16 handle, u16 cmd,
439 const void *obuf, unsigned obuf_len,
440 void *ibuf, unsigned *ibuf_len)
441 {
442 int ret = 0;
443 int rx_slot;
444 struct dln2_response *rsp;
445 struct dln2_rx_context *rxc;
446 struct device *dev = &dln2->interface->dev;
447 const unsigned long timeout = msecs_to_jiffies(DLN2_USB_TIMEOUT);
448 struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle];
449 int size;
450
451 spin_lock(&dln2->disconnect_lock);
452 if (!dln2->disconnect)
453 dln2->active_transfers++;
454 else
455 ret = -ENODEV;
456 spin_unlock(&dln2->disconnect_lock);
457
458 if (ret)
459 return ret;
460
461 rx_slot = alloc_rx_slot(dln2, handle);
462 if (rx_slot < 0) {
463 ret = rx_slot;
464 goto out_decr;
465 }
466
467 ret = dln2_send_wait(dln2, handle, cmd, rx_slot, obuf, obuf_len);
468 if (ret < 0) {
469 dev_err(dev, "USB write failed: %d\n", ret);
470 goto out_free_rx_slot;
471 }
472
473 rxc = &rxs->slots[rx_slot];
474
475 ret = wait_for_completion_interruptible_timeout(&rxc->done, timeout);
476 if (ret <= 0) {
477 if (!ret)
478 ret = -ETIMEDOUT;
479 goto out_free_rx_slot;
480 } else {
481 ret = 0;
482 }
483
484 if (dln2->disconnect) {
485 ret = -ENODEV;
486 goto out_free_rx_slot;
487 }
488
489 /* if we got here we know that the response header has been checked */
490 rsp = rxc->urb->transfer_buffer;
491 size = le16_to_cpu(rsp->hdr.size);
492
493 if (size < sizeof(*rsp)) {
494 ret = -EPROTO;
495 goto out_free_rx_slot;
496 }
497
498 if (le16_to_cpu(rsp->result) > 0x80) {
499 dev_dbg(dev, "%d received response with error %d\n",
500 handle, le16_to_cpu(rsp->result));
501 ret = -EREMOTEIO;
502 goto out_free_rx_slot;
503 }
504
505 if (!ibuf)
506 goto out_free_rx_slot;
507
508 if (*ibuf_len > size - sizeof(*rsp))
509 *ibuf_len = size - sizeof(*rsp);
510
511 memcpy(ibuf, rsp + 1, *ibuf_len);
512
513 out_free_rx_slot:
514 free_rx_slot(dln2, handle, rx_slot);
515 out_decr:
516 spin_lock(&dln2->disconnect_lock);
517 dln2->active_transfers--;
518 spin_unlock(&dln2->disconnect_lock);
519 if (dln2->disconnect)
520 wake_up(&dln2->disconnect_wq);
521
522 return ret;
523 }
524
dln2_transfer(struct platform_device * pdev,u16 cmd,const void * obuf,unsigned obuf_len,void * ibuf,unsigned * ibuf_len)525 int dln2_transfer(struct platform_device *pdev, u16 cmd,
526 const void *obuf, unsigned obuf_len,
527 void *ibuf, unsigned *ibuf_len)
528 {
529 struct dln2_platform_data *dln2_pdata;
530 struct dln2_dev *dln2;
531 u16 handle;
532
533 dln2 = dev_get_drvdata(pdev->dev.parent);
534 dln2_pdata = dev_get_platdata(&pdev->dev);
535 handle = dln2_pdata->handle;
536
537 return _dln2_transfer(dln2, handle, cmd, obuf, obuf_len, ibuf,
538 ibuf_len);
539 }
540 EXPORT_SYMBOL(dln2_transfer);
541
dln2_check_hw(struct dln2_dev * dln2)542 static int dln2_check_hw(struct dln2_dev *dln2)
543 {
544 int ret;
545 __le32 hw_type;
546 int len = sizeof(hw_type);
547
548 ret = _dln2_transfer(dln2, DLN2_HANDLE_CTRL, CMD_GET_DEVICE_VER,
549 NULL, 0, &hw_type, &len);
550 if (ret < 0)
551 return ret;
552 if (len < sizeof(hw_type))
553 return -EREMOTEIO;
554
555 if (le32_to_cpu(hw_type) != DLN2_HW_ID) {
556 dev_err(&dln2->interface->dev, "Device ID 0x%x not supported\n",
557 le32_to_cpu(hw_type));
558 return -ENODEV;
559 }
560
561 return 0;
562 }
563
dln2_print_serialno(struct dln2_dev * dln2)564 static int dln2_print_serialno(struct dln2_dev *dln2)
565 {
566 int ret;
567 __le32 serial_no;
568 int len = sizeof(serial_no);
569 struct device *dev = &dln2->interface->dev;
570
571 ret = _dln2_transfer(dln2, DLN2_HANDLE_CTRL, CMD_GET_DEVICE_SN, NULL, 0,
572 &serial_no, &len);
573 if (ret < 0)
574 return ret;
575 if (len < sizeof(serial_no))
576 return -EREMOTEIO;
577
578 dev_info(dev, "Diolan DLN2 serial %u\n", le32_to_cpu(serial_no));
579
580 return 0;
581 }
582
dln2_hw_init(struct dln2_dev * dln2)583 static int dln2_hw_init(struct dln2_dev *dln2)
584 {
585 int ret;
586
587 ret = dln2_check_hw(dln2);
588 if (ret < 0)
589 return ret;
590
591 return dln2_print_serialno(dln2);
592 }
593
dln2_free_rx_urbs(struct dln2_dev * dln2)594 static void dln2_free_rx_urbs(struct dln2_dev *dln2)
595 {
596 int i;
597
598 for (i = 0; i < DLN2_MAX_URBS; i++) {
599 usb_free_urb(dln2->rx_urb[i]);
600 kfree(dln2->rx_buf[i]);
601 }
602 }
603
dln2_stop_rx_urbs(struct dln2_dev * dln2)604 static void dln2_stop_rx_urbs(struct dln2_dev *dln2)
605 {
606 int i;
607
608 for (i = 0; i < DLN2_MAX_URBS; i++)
609 usb_kill_urb(dln2->rx_urb[i]);
610 }
611
dln2_free(struct dln2_dev * dln2)612 static void dln2_free(struct dln2_dev *dln2)
613 {
614 dln2_free_rx_urbs(dln2);
615 usb_put_dev(dln2->usb_dev);
616 kfree(dln2);
617 }
618
dln2_setup_rx_urbs(struct dln2_dev * dln2,struct usb_host_interface * hostif)619 static int dln2_setup_rx_urbs(struct dln2_dev *dln2,
620 struct usb_host_interface *hostif)
621 {
622 int i;
623 const int rx_max_size = DLN2_RX_BUF_SIZE;
624
625 for (i = 0; i < DLN2_MAX_URBS; i++) {
626 dln2->rx_buf[i] = kmalloc(rx_max_size, GFP_KERNEL);
627 if (!dln2->rx_buf[i])
628 return -ENOMEM;
629
630 dln2->rx_urb[i] = usb_alloc_urb(0, GFP_KERNEL);
631 if (!dln2->rx_urb[i])
632 return -ENOMEM;
633
634 usb_fill_bulk_urb(dln2->rx_urb[i], dln2->usb_dev,
635 usb_rcvbulkpipe(dln2->usb_dev, dln2->ep_in),
636 dln2->rx_buf[i], rx_max_size, dln2_rx, dln2);
637 }
638
639 return 0;
640 }
641
dln2_start_rx_urbs(struct dln2_dev * dln2,gfp_t gfp)642 static int dln2_start_rx_urbs(struct dln2_dev *dln2, gfp_t gfp)
643 {
644 struct device *dev = &dln2->interface->dev;
645 int ret;
646 int i;
647
648 for (i = 0; i < DLN2_MAX_URBS; i++) {
649 ret = usb_submit_urb(dln2->rx_urb[i], gfp);
650 if (ret < 0) {
651 dev_err(dev, "failed to submit RX URB: %d\n", ret);
652 return ret;
653 }
654 }
655
656 return 0;
657 }
658
659 static struct dln2_platform_data dln2_pdata_gpio = {
660 .handle = DLN2_HANDLE_GPIO,
661 };
662
663 /* Only one I2C port seems to be supported on current hardware */
664 static struct dln2_platform_data dln2_pdata_i2c = {
665 .handle = DLN2_HANDLE_I2C,
666 .port = 0,
667 };
668
669 /* Only one SPI port supported */
670 static struct dln2_platform_data dln2_pdata_spi = {
671 .handle = DLN2_HANDLE_SPI,
672 .port = 0,
673 };
674
675 static const struct mfd_cell dln2_devs[] = {
676 {
677 .name = "dln2-gpio",
678 .platform_data = &dln2_pdata_gpio,
679 .pdata_size = sizeof(struct dln2_platform_data),
680 },
681 {
682 .name = "dln2-i2c",
683 .platform_data = &dln2_pdata_i2c,
684 .pdata_size = sizeof(struct dln2_platform_data),
685 },
686 {
687 .name = "dln2-spi",
688 .platform_data = &dln2_pdata_spi,
689 .pdata_size = sizeof(struct dln2_platform_data),
690 },
691 };
692
dln2_stop(struct dln2_dev * dln2)693 static void dln2_stop(struct dln2_dev *dln2)
694 {
695 int i, j;
696
697 /* don't allow starting new transfers */
698 spin_lock(&dln2->disconnect_lock);
699 dln2->disconnect = true;
700 spin_unlock(&dln2->disconnect_lock);
701
702 /* cancel in progress transfers */
703 for (i = 0; i < DLN2_HANDLES; i++) {
704 struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[i];
705 unsigned long flags;
706
707 spin_lock_irqsave(&rxs->lock, flags);
708
709 /* cancel all response waiters */
710 for (j = 0; j < DLN2_MAX_RX_SLOTS; j++) {
711 struct dln2_rx_context *rxc = &rxs->slots[j];
712
713 if (rxc->in_use)
714 complete(&rxc->done);
715 }
716
717 spin_unlock_irqrestore(&rxs->lock, flags);
718 }
719
720 /* wait for transfers to end */
721 wait_event(dln2->disconnect_wq, !dln2->active_transfers);
722
723 dln2_stop_rx_urbs(dln2);
724 }
725
dln2_disconnect(struct usb_interface * interface)726 static void dln2_disconnect(struct usb_interface *interface)
727 {
728 struct dln2_dev *dln2 = usb_get_intfdata(interface);
729
730 dln2_stop(dln2);
731
732 mfd_remove_devices(&interface->dev);
733
734 dln2_free(dln2);
735 }
736
dln2_probe(struct usb_interface * interface,const struct usb_device_id * usb_id)737 static int dln2_probe(struct usb_interface *interface,
738 const struct usb_device_id *usb_id)
739 {
740 struct usb_host_interface *hostif = interface->cur_altsetting;
741 struct usb_endpoint_descriptor *epin;
742 struct usb_endpoint_descriptor *epout;
743 struct device *dev = &interface->dev;
744 struct dln2_dev *dln2;
745 int ret;
746 int i, j;
747
748 if (hostif->desc.bInterfaceNumber != 0 ||
749 hostif->desc.bNumEndpoints < 2)
750 return -ENODEV;
751
752 epout = &hostif->endpoint[DLN2_EP_OUT].desc;
753 if (!usb_endpoint_is_bulk_out(epout))
754 return -ENODEV;
755 epin = &hostif->endpoint[DLN2_EP_IN].desc;
756 if (!usb_endpoint_is_bulk_in(epin))
757 return -ENODEV;
758
759 dln2 = kzalloc(sizeof(*dln2), GFP_KERNEL);
760 if (!dln2)
761 return -ENOMEM;
762
763 dln2->ep_out = epout->bEndpointAddress;
764 dln2->ep_in = epin->bEndpointAddress;
765 dln2->usb_dev = usb_get_dev(interface_to_usbdev(interface));
766 dln2->interface = interface;
767 usb_set_intfdata(interface, dln2);
768 init_waitqueue_head(&dln2->disconnect_wq);
769
770 for (i = 0; i < DLN2_HANDLES; i++) {
771 init_waitqueue_head(&dln2->mod_rx_slots[i].wq);
772 spin_lock_init(&dln2->mod_rx_slots[i].lock);
773 for (j = 0; j < DLN2_MAX_RX_SLOTS; j++)
774 init_completion(&dln2->mod_rx_slots[i].slots[j].done);
775 }
776
777 spin_lock_init(&dln2->event_cb_lock);
778 spin_lock_init(&dln2->disconnect_lock);
779 INIT_LIST_HEAD(&dln2->event_cb_list);
780
781 ret = dln2_setup_rx_urbs(dln2, hostif);
782 if (ret)
783 goto out_free;
784
785 ret = dln2_start_rx_urbs(dln2, GFP_KERNEL);
786 if (ret)
787 goto out_stop_rx;
788
789 ret = dln2_hw_init(dln2);
790 if (ret < 0) {
791 dev_err(dev, "failed to initialize hardware\n");
792 goto out_stop_rx;
793 }
794
795 ret = mfd_add_hotplug_devices(dev, dln2_devs, ARRAY_SIZE(dln2_devs));
796 if (ret != 0) {
797 dev_err(dev, "failed to add mfd devices to core\n");
798 goto out_stop_rx;
799 }
800
801 return 0;
802
803 out_stop_rx:
804 dln2_stop_rx_urbs(dln2);
805
806 out_free:
807 dln2_free(dln2);
808
809 return ret;
810 }
811
dln2_suspend(struct usb_interface * iface,pm_message_t message)812 static int dln2_suspend(struct usb_interface *iface, pm_message_t message)
813 {
814 struct dln2_dev *dln2 = usb_get_intfdata(iface);
815
816 dln2_stop(dln2);
817
818 return 0;
819 }
820
dln2_resume(struct usb_interface * iface)821 static int dln2_resume(struct usb_interface *iface)
822 {
823 struct dln2_dev *dln2 = usb_get_intfdata(iface);
824
825 dln2->disconnect = false;
826
827 return dln2_start_rx_urbs(dln2, GFP_NOIO);
828 }
829
830 static const struct usb_device_id dln2_table[] = {
831 { USB_DEVICE(0xa257, 0x2013) },
832 { }
833 };
834
835 MODULE_DEVICE_TABLE(usb, dln2_table);
836
837 static struct usb_driver dln2_driver = {
838 .name = "dln2",
839 .probe = dln2_probe,
840 .disconnect = dln2_disconnect,
841 .id_table = dln2_table,
842 .suspend = dln2_suspend,
843 .resume = dln2_resume,
844 };
845
846 module_usb_driver(dln2_driver);
847
848 MODULE_AUTHOR("Octavian Purdila <octavian.purdila@intel.com>");
849 MODULE_DESCRIPTION("Core driver for the Diolan DLN2 interface adapter");
850 MODULE_LICENSE("GPL v2");
851