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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Driver for the Diolan DLN-2 USB adapter
4 *
5 * Copyright (c) 2014 Intel Corporation
6 *
7 * Derived from:
8 * i2c-diolan-u2c.c
9 * Copyright (c) 2010-2011 Ericsson AB
10 */
11
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/types.h>
15#include <linux/slab.h>
16#include <linux/usb.h>
17#include <linux/i2c.h>
18#include <linux/mutex.h>
19#include <linux/platform_device.h>
20#include <linux/mfd/core.h>
21#include <linux/mfd/dln2.h>
22#include <linux/rculist.h>
23
24struct dln2_header {
25 __le16 size;
26 __le16 id;
27 __le16 echo;
28 __le16 handle;
29};
30
31struct dln2_response {
32 struct dln2_header hdr;
33 __le16 result;
34};
35
36#define DLN2_GENERIC_MODULE_ID 0x00
37#define DLN2_GENERIC_CMD(cmd) DLN2_CMD(cmd, DLN2_GENERIC_MODULE_ID)
38#define CMD_GET_DEVICE_VER DLN2_GENERIC_CMD(0x30)
39#define CMD_GET_DEVICE_SN DLN2_GENERIC_CMD(0x31)
40
41#define DLN2_HW_ID 0x200
42#define DLN2_USB_TIMEOUT 200 /* in ms */
43#define DLN2_MAX_RX_SLOTS 16
44#define DLN2_MAX_URBS 16
45#define DLN2_RX_BUF_SIZE 512
46
47enum dln2_handle {
48 DLN2_HANDLE_EVENT = 0, /* don't change, hardware defined */
49 DLN2_HANDLE_CTRL,
50 DLN2_HANDLE_GPIO,
51 DLN2_HANDLE_I2C,
52 DLN2_HANDLE_SPI,
53 DLN2_HANDLE_ADC,
54 DLN2_HANDLES
55};
56
57/*
58 * Receive context used between the receive demultiplexer and the transfer
59 * routine. While sending a request the transfer routine will look for a free
60 * receive context and use it to wait for a response and to receive the URB and
61 * thus the response data.
62 */
63struct dln2_rx_context {
64 /* completion used to wait for a response */
65 struct completion done;
66
67 /* if non-NULL the URB contains the response */
68 struct urb *urb;
69
70 /* if true then this context is used to wait for a response */
71 bool in_use;
72};
73
74/*
75 * Receive contexts for a particular DLN2 module (i2c, gpio, etc.). We use the
76 * handle header field to identify the module in dln2_dev.mod_rx_slots and then
77 * the echo header field to index the slots field and find the receive context
78 * for a particular request.
79 */
80struct dln2_mod_rx_slots {
81 /* RX slots bitmap */
82 DECLARE_BITMAP(bmap, DLN2_MAX_RX_SLOTS);
83
84 /* used to wait for a free RX slot */
85 wait_queue_head_t wq;
86
87 /* used to wait for an RX operation to complete */
88 struct dln2_rx_context slots[DLN2_MAX_RX_SLOTS];
89
90 /* avoid races between alloc/free_rx_slot and dln2_rx_transfer */
91 spinlock_t lock;
92};
93
94struct dln2_dev {
95 struct usb_device *usb_dev;
96 struct usb_interface *interface;
97 u8 ep_in;
98 u8 ep_out;
99
100 struct urb *rx_urb[DLN2_MAX_URBS];
101 void *rx_buf[DLN2_MAX_URBS];
102
103 struct dln2_mod_rx_slots mod_rx_slots[DLN2_HANDLES];
104
105 struct list_head event_cb_list;
106 spinlock_t event_cb_lock;
107
108 bool disconnect;
109 int active_transfers;
110 wait_queue_head_t disconnect_wq;
111 spinlock_t disconnect_lock;
112};
113
114struct dln2_event_cb_entry {
115 struct list_head list;
116 u16 id;
117 struct platform_device *pdev;
118 dln2_event_cb_t callback;
119};
120
121int dln2_register_event_cb(struct platform_device *pdev, u16 id,
122 dln2_event_cb_t event_cb)
123{
124 struct dln2_dev *dln2 = dev_get_drvdata(pdev->dev.parent);
125 struct dln2_event_cb_entry *i, *entry;
126 unsigned long flags;
127 int ret = 0;
128
129 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
130 if (!entry)
131 return -ENOMEM;
132
133 entry->id = id;
134 entry->callback = event_cb;
135 entry->pdev = pdev;
136
137 spin_lock_irqsave(&dln2->event_cb_lock, flags);
138
139 list_for_each_entry(i, &dln2->event_cb_list, list) {
140 if (i->id == id) {
141 ret = -EBUSY;
142 break;
143 }
144 }
145
146 if (!ret)
147 list_add_rcu(&entry->list, &dln2->event_cb_list);
148
149 spin_unlock_irqrestore(&dln2->event_cb_lock, flags);
150
151 if (ret)
152 kfree(entry);
153
154 return ret;
155}
156EXPORT_SYMBOL(dln2_register_event_cb);
157
158void dln2_unregister_event_cb(struct platform_device *pdev, u16 id)
159{
160 struct dln2_dev *dln2 = dev_get_drvdata(pdev->dev.parent);
161 struct dln2_event_cb_entry *i;
162 unsigned long flags;
163 bool found = false;
164
165 spin_lock_irqsave(&dln2->event_cb_lock, flags);
166
167 list_for_each_entry(i, &dln2->event_cb_list, list) {
168 if (i->id == id) {
169 list_del_rcu(&i->list);
170 found = true;
171 break;
172 }
173 }
174
175 spin_unlock_irqrestore(&dln2->event_cb_lock, flags);
176
177 if (found) {
178 synchronize_rcu();
179 kfree(i);
180 }
181}
182EXPORT_SYMBOL(dln2_unregister_event_cb);
183
184/*
185 * Returns true if a valid transfer slot is found. In this case the URB must not
186 * be resubmitted immediately in dln2_rx as we need the data when dln2_transfer
187 * is woke up. It will be resubmitted there.
188 */
189static bool dln2_transfer_complete(struct dln2_dev *dln2, struct urb *urb,
190 u16 handle, u16 rx_slot)
191{
192 struct device *dev = &dln2->interface->dev;
193 struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle];
194 struct dln2_rx_context *rxc;
195 unsigned long flags;
196 bool valid_slot = false;
197
198 if (rx_slot >= DLN2_MAX_RX_SLOTS)
199 goto out;
200
201 rxc = &rxs->slots[rx_slot];
202
203 spin_lock_irqsave(&rxs->lock, flags);
204 if (rxc->in_use && !rxc->urb) {
205 rxc->urb = urb;
206 complete(&rxc->done);
207 valid_slot = true;
208 }
209 spin_unlock_irqrestore(&rxs->lock, flags);
210
211out:
212 if (!valid_slot)
213 dev_warn(dev, "bad/late response %d/%d\n", handle, rx_slot);
214
215 return valid_slot;
216}
217
218static void dln2_run_event_callbacks(struct dln2_dev *dln2, u16 id, u16 echo,
219 void *data, int len)
220{
221 struct dln2_event_cb_entry *i;
222
223 rcu_read_lock();
224
225 list_for_each_entry_rcu(i, &dln2->event_cb_list, list) {
226 if (i->id == id) {
227 i->callback(i->pdev, echo, data, len);
228 break;
229 }
230 }
231
232 rcu_read_unlock();
233}
234
235static void dln2_rx(struct urb *urb)
236{
237 struct dln2_dev *dln2 = urb->context;
238 struct dln2_header *hdr = urb->transfer_buffer;
239 struct device *dev = &dln2->interface->dev;
240 u16 id, echo, handle, size;
241 u8 *data;
242 int len;
243 int err;
244
245 switch (urb->status) {
246 case 0:
247 /* success */
248 break;
249 case -ECONNRESET:
250 case -ENOENT:
251 case -ESHUTDOWN:
252 case -EPIPE:
253 /* this urb is terminated, clean up */
254 dev_dbg(dev, "urb shutting down with status %d\n", urb->status);
255 return;
256 default:
257 dev_dbg(dev, "nonzero urb status received %d\n", urb->status);
258 goto out;
259 }
260
261 if (urb->actual_length < sizeof(struct dln2_header)) {
262 dev_err(dev, "short response: %d\n", urb->actual_length);
263 goto out;
264 }
265
266 handle = le16_to_cpu(hdr->handle);
267 id = le16_to_cpu(hdr->id);
268 echo = le16_to_cpu(hdr->echo);
269 size = le16_to_cpu(hdr->size);
270
271 if (size != urb->actual_length) {
272 dev_err(dev, "size mismatch: handle %x cmd %x echo %x size %d actual %d\n",
273 handle, id, echo, size, urb->actual_length);
274 goto out;
275 }
276
277 if (handle >= DLN2_HANDLES) {
278 dev_warn(dev, "invalid handle %d\n", handle);
279 goto out;
280 }
281
282 data = urb->transfer_buffer + sizeof(struct dln2_header);
283 len = urb->actual_length - sizeof(struct dln2_header);
284
285 if (handle == DLN2_HANDLE_EVENT) {
286 unsigned long flags;
287
288 spin_lock_irqsave(&dln2->event_cb_lock, flags);
289 dln2_run_event_callbacks(dln2, id, echo, data, len);
290 spin_unlock_irqrestore(&dln2->event_cb_lock, flags);
291 } else {
292 /* URB will be re-submitted in _dln2_transfer (free_rx_slot) */
293 if (dln2_transfer_complete(dln2, urb, handle, echo))
294 return;
295 }
296
297out:
298 err = usb_submit_urb(urb, GFP_ATOMIC);
299 if (err < 0)
300 dev_err(dev, "failed to resubmit RX URB: %d\n", err);
301}
302
303static void *dln2_prep_buf(u16 handle, u16 cmd, u16 echo, const void *obuf,
304 int *obuf_len, gfp_t gfp)
305{
306 int len;
307 void *buf;
308 struct dln2_header *hdr;
309
310 len = *obuf_len + sizeof(*hdr);
311 buf = kmalloc(len, gfp);
312 if (!buf)
313 return NULL;
314
315 hdr = (struct dln2_header *)buf;
316 hdr->id = cpu_to_le16(cmd);
317 hdr->size = cpu_to_le16(len);
318 hdr->echo = cpu_to_le16(echo);
319 hdr->handle = cpu_to_le16(handle);
320
321 memcpy(buf + sizeof(*hdr), obuf, *obuf_len);
322
323 *obuf_len = len;
324
325 return buf;
326}
327
328static int dln2_send_wait(struct dln2_dev *dln2, u16 handle, u16 cmd, u16 echo,
329 const void *obuf, int obuf_len)
330{
331 int ret = 0;
332 int len = obuf_len;
333 void *buf;
334 int actual;
335
336 buf = dln2_prep_buf(handle, cmd, echo, obuf, &len, GFP_KERNEL);
337 if (!buf)
338 return -ENOMEM;
339
340 ret = usb_bulk_msg(dln2->usb_dev,
341 usb_sndbulkpipe(dln2->usb_dev, dln2->ep_out),
342 buf, len, &actual, DLN2_USB_TIMEOUT);
343
344 kfree(buf);
345
346 return ret;
347}
348
349static bool find_free_slot(struct dln2_dev *dln2, u16 handle, int *slot)
350{
351 struct dln2_mod_rx_slots *rxs;
352 unsigned long flags;
353
354 if (dln2->disconnect) {
355 *slot = -ENODEV;
356 return true;
357 }
358
359 rxs = &dln2->mod_rx_slots[handle];
360
361 spin_lock_irqsave(&rxs->lock, flags);
362
363 *slot = find_first_zero_bit(rxs->bmap, DLN2_MAX_RX_SLOTS);
364
365 if (*slot < DLN2_MAX_RX_SLOTS) {
366 struct dln2_rx_context *rxc = &rxs->slots[*slot];
367
368 set_bit(*slot, rxs->bmap);
369 rxc->in_use = true;
370 }
371
372 spin_unlock_irqrestore(&rxs->lock, flags);
373
374 return *slot < DLN2_MAX_RX_SLOTS;
375}
376
377static int alloc_rx_slot(struct dln2_dev *dln2, u16 handle)
378{
379 int ret;
380 int slot;
381
382 /*
383 * No need to timeout here, the wait is bounded by the timeout in
384 * _dln2_transfer.
385 */
386 ret = wait_event_interruptible(dln2->mod_rx_slots[handle].wq,
387 find_free_slot(dln2, handle, &slot));
388 if (ret < 0)
389 return ret;
390
391 return slot;
392}
393
394static void free_rx_slot(struct dln2_dev *dln2, u16 handle, int slot)
395{
396 struct dln2_mod_rx_slots *rxs;
397 struct urb *urb = NULL;
398 unsigned long flags;
399 struct dln2_rx_context *rxc;
400
401 rxs = &dln2->mod_rx_slots[handle];
402
403 spin_lock_irqsave(&rxs->lock, flags);
404
405 clear_bit(slot, rxs->bmap);
406
407 rxc = &rxs->slots[slot];
408 rxc->in_use = false;
409 urb = rxc->urb;
410 rxc->urb = NULL;
411 reinit_completion(&rxc->done);
412
413 spin_unlock_irqrestore(&rxs->lock, flags);
414
415 if (urb) {
416 int err;
417 struct device *dev = &dln2->interface->dev;
418
419 err = usb_submit_urb(urb, GFP_KERNEL);
420 if (err < 0)
421 dev_err(dev, "failed to resubmit RX URB: %d\n", err);
422 }
423
424 wake_up_interruptible(&rxs->wq);
425}
426
427static int _dln2_transfer(struct dln2_dev *dln2, u16 handle, u16 cmd,
428 const void *obuf, unsigned obuf_len,
429 void *ibuf, unsigned *ibuf_len)
430{
431 int ret = 0;
432 int rx_slot;
433 struct dln2_response *rsp;
434 struct dln2_rx_context *rxc;
435 struct device *dev = &dln2->interface->dev;
436 const unsigned long timeout = msecs_to_jiffies(DLN2_USB_TIMEOUT);
437 struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle];
438 int size;
439
440 spin_lock(&dln2->disconnect_lock);
441 if (!dln2->disconnect)
442 dln2->active_transfers++;
443 else
444 ret = -ENODEV;
445 spin_unlock(&dln2->disconnect_lock);
446
447 if (ret)
448 return ret;
449
450 rx_slot = alloc_rx_slot(dln2, handle);
451 if (rx_slot < 0) {
452 ret = rx_slot;
453 goto out_decr;
454 }
455
456 ret = dln2_send_wait(dln2, handle, cmd, rx_slot, obuf, obuf_len);
457 if (ret < 0) {
458 dev_err(dev, "USB write failed: %d\n", ret);
459 goto out_free_rx_slot;
460 }
461
462 rxc = &rxs->slots[rx_slot];
463
464 ret = wait_for_completion_interruptible_timeout(&rxc->done, timeout);
465 if (ret <= 0) {
466 if (!ret)
467 ret = -ETIMEDOUT;
468 goto out_free_rx_slot;
469 } else {
470 ret = 0;
471 }
472
473 if (dln2->disconnect) {
474 ret = -ENODEV;
475 goto out_free_rx_slot;
476 }
477
478 /* if we got here we know that the response header has been checked */
479 rsp = rxc->urb->transfer_buffer;
480 size = le16_to_cpu(rsp->hdr.size);
481
482 if (size < sizeof(*rsp)) {
483 ret = -EPROTO;
484 goto out_free_rx_slot;
485 }
486
487 if (le16_to_cpu(rsp->result) > 0x80) {
488 dev_dbg(dev, "%d received response with error %d\n",
489 handle, le16_to_cpu(rsp->result));
490 ret = -EREMOTEIO;
491 goto out_free_rx_slot;
492 }
493
494 if (!ibuf)
495 goto out_free_rx_slot;
496
497 if (*ibuf_len > size - sizeof(*rsp))
498 *ibuf_len = size - sizeof(*rsp);
499
500 memcpy(ibuf, rsp + 1, *ibuf_len);
501
502out_free_rx_slot:
503 free_rx_slot(dln2, handle, rx_slot);
504out_decr:
505 spin_lock(&dln2->disconnect_lock);
506 dln2->active_transfers--;
507 spin_unlock(&dln2->disconnect_lock);
508 if (dln2->disconnect)
509 wake_up(&dln2->disconnect_wq);
510
511 return ret;
512}
513
514int dln2_transfer(struct platform_device *pdev, u16 cmd,
515 const void *obuf, unsigned obuf_len,
516 void *ibuf, unsigned *ibuf_len)
517{
518 struct dln2_platform_data *dln2_pdata;
519 struct dln2_dev *dln2;
520 u16 handle;
521
522 dln2 = dev_get_drvdata(pdev->dev.parent);
523 dln2_pdata = dev_get_platdata(&pdev->dev);
524 handle = dln2_pdata->handle;
525
526 return _dln2_transfer(dln2, handle, cmd, obuf, obuf_len, ibuf,
527 ibuf_len);
528}
529EXPORT_SYMBOL(dln2_transfer);
530
531static int dln2_check_hw(struct dln2_dev *dln2)
532{
533 int ret;
534 __le32 hw_type;
535 int len = sizeof(hw_type);
536
537 ret = _dln2_transfer(dln2, DLN2_HANDLE_CTRL, CMD_GET_DEVICE_VER,
538 NULL, 0, &hw_type, &len);
539 if (ret < 0)
540 return ret;
541 if (len < sizeof(hw_type))
542 return -EREMOTEIO;
543
544 if (le32_to_cpu(hw_type) != DLN2_HW_ID) {
545 dev_err(&dln2->interface->dev, "Device ID 0x%x not supported\n",
546 le32_to_cpu(hw_type));
547 return -ENODEV;
548 }
549
550 return 0;
551}
552
553static int dln2_print_serialno(struct dln2_dev *dln2)
554{
555 int ret;
556 __le32 serial_no;
557 int len = sizeof(serial_no);
558 struct device *dev = &dln2->interface->dev;
559
560 ret = _dln2_transfer(dln2, DLN2_HANDLE_CTRL, CMD_GET_DEVICE_SN, NULL, 0,
561 &serial_no, &len);
562 if (ret < 0)
563 return ret;
564 if (len < sizeof(serial_no))
565 return -EREMOTEIO;
566
567 dev_info(dev, "Diolan DLN2 serial %u\n", le32_to_cpu(serial_no));
568
569 return 0;
570}
571
572static int dln2_hw_init(struct dln2_dev *dln2)
573{
574 int ret;
575
576 ret = dln2_check_hw(dln2);
577 if (ret < 0)
578 return ret;
579
580 return dln2_print_serialno(dln2);
581}
582
583static void dln2_free_rx_urbs(struct dln2_dev *dln2)
584{
585 int i;
586
587 for (i = 0; i < DLN2_MAX_URBS; i++) {
588 usb_free_urb(dln2->rx_urb[i]);
589 kfree(dln2->rx_buf[i]);
590 }
591}
592
593static void dln2_stop_rx_urbs(struct dln2_dev *dln2)
594{
595 int i;
596
597 for (i = 0; i < DLN2_MAX_URBS; i++)
598 usb_kill_urb(dln2->rx_urb[i]);
599}
600
601static void dln2_free(struct dln2_dev *dln2)
602{
603 dln2_free_rx_urbs(dln2);
604 usb_put_dev(dln2->usb_dev);
605 kfree(dln2);
606}
607
608static int dln2_setup_rx_urbs(struct dln2_dev *dln2,
609 struct usb_host_interface *hostif)
610{
611 int i;
612 const int rx_max_size = DLN2_RX_BUF_SIZE;
613
614 for (i = 0; i < DLN2_MAX_URBS; i++) {
615 dln2->rx_buf[i] = kmalloc(rx_max_size, GFP_KERNEL);
616 if (!dln2->rx_buf[i])
617 return -ENOMEM;
618
619 dln2->rx_urb[i] = usb_alloc_urb(0, GFP_KERNEL);
620 if (!dln2->rx_urb[i])
621 return -ENOMEM;
622
623 usb_fill_bulk_urb(dln2->rx_urb[i], dln2->usb_dev,
624 usb_rcvbulkpipe(dln2->usb_dev, dln2->ep_in),
625 dln2->rx_buf[i], rx_max_size, dln2_rx, dln2);
626 }
627
628 return 0;
629}
630
631static int dln2_start_rx_urbs(struct dln2_dev *dln2, gfp_t gfp)
632{
633 struct device *dev = &dln2->interface->dev;
634 int ret;
635 int i;
636
637 for (i = 0; i < DLN2_MAX_URBS; i++) {
638 ret = usb_submit_urb(dln2->rx_urb[i], gfp);
639 if (ret < 0) {
640 dev_err(dev, "failed to submit RX URB: %d\n", ret);
641 return ret;
642 }
643 }
644
645 return 0;
646}
647
648enum {
649 DLN2_ACPI_MATCH_GPIO = 0,
650 DLN2_ACPI_MATCH_I2C = 1,
651 DLN2_ACPI_MATCH_SPI = 2,
652 DLN2_ACPI_MATCH_ADC = 3,
653};
654
655static struct dln2_platform_data dln2_pdata_gpio = {
656 .handle = DLN2_HANDLE_GPIO,
657};
658
659static struct mfd_cell_acpi_match dln2_acpi_match_gpio = {
660 .adr = DLN2_ACPI_MATCH_GPIO,
661};
662
663/* Only one I2C port seems to be supported on current hardware */
664static struct dln2_platform_data dln2_pdata_i2c = {
665 .handle = DLN2_HANDLE_I2C,
666 .port = 0,
667};
668
669static struct mfd_cell_acpi_match dln2_acpi_match_i2c = {
670 .adr = DLN2_ACPI_MATCH_I2C,
671};
672
673/* Only one SPI port supported */
674static struct dln2_platform_data dln2_pdata_spi = {
675 .handle = DLN2_HANDLE_SPI,
676 .port = 0,
677};
678
679static struct mfd_cell_acpi_match dln2_acpi_match_spi = {
680 .adr = DLN2_ACPI_MATCH_SPI,
681};
682
683/* Only one ADC port supported */
684static struct dln2_platform_data dln2_pdata_adc = {
685 .handle = DLN2_HANDLE_ADC,
686 .port = 0,
687};
688
689static struct mfd_cell_acpi_match dln2_acpi_match_adc = {
690 .adr = DLN2_ACPI_MATCH_ADC,
691};
692
693static const struct mfd_cell dln2_devs[] = {
694 {
695 .name = "dln2-gpio",
696 .acpi_match = &dln2_acpi_match_gpio,
697 .platform_data = &dln2_pdata_gpio,
698 .pdata_size = sizeof(struct dln2_platform_data),
699 },
700 {
701 .name = "dln2-i2c",
702 .acpi_match = &dln2_acpi_match_i2c,
703 .platform_data = &dln2_pdata_i2c,
704 .pdata_size = sizeof(struct dln2_platform_data),
705 },
706 {
707 .name = "dln2-spi",
708 .acpi_match = &dln2_acpi_match_spi,
709 .platform_data = &dln2_pdata_spi,
710 .pdata_size = sizeof(struct dln2_platform_data),
711 },
712 {
713 .name = "dln2-adc",
714 .acpi_match = &dln2_acpi_match_adc,
715 .platform_data = &dln2_pdata_adc,
716 .pdata_size = sizeof(struct dln2_platform_data),
717 },
718};
719
720static void dln2_stop(struct dln2_dev *dln2)
721{
722 int i, j;
723
724 /* don't allow starting new transfers */
725 spin_lock(&dln2->disconnect_lock);
726 dln2->disconnect = true;
727 spin_unlock(&dln2->disconnect_lock);
728
729 /* cancel in progress transfers */
730 for (i = 0; i < DLN2_HANDLES; i++) {
731 struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[i];
732 unsigned long flags;
733
734 spin_lock_irqsave(&rxs->lock, flags);
735
736 /* cancel all response waiters */
737 for (j = 0; j < DLN2_MAX_RX_SLOTS; j++) {
738 struct dln2_rx_context *rxc = &rxs->slots[j];
739
740 if (rxc->in_use)
741 complete(&rxc->done);
742 }
743
744 spin_unlock_irqrestore(&rxs->lock, flags);
745 }
746
747 /* wait for transfers to end */
748 wait_event(dln2->disconnect_wq, !dln2->active_transfers);
749
750 dln2_stop_rx_urbs(dln2);
751}
752
753static void dln2_disconnect(struct usb_interface *interface)
754{
755 struct dln2_dev *dln2 = usb_get_intfdata(interface);
756
757 dln2_stop(dln2);
758
759 mfd_remove_devices(&interface->dev);
760
761 dln2_free(dln2);
762}
763
764static int dln2_probe(struct usb_interface *interface,
765 const struct usb_device_id *usb_id)
766{
767 struct usb_host_interface *hostif = interface->cur_altsetting;
768 struct usb_endpoint_descriptor *epin;
769 struct usb_endpoint_descriptor *epout;
770 struct device *dev = &interface->dev;
771 struct dln2_dev *dln2;
772 int ret;
773 int i, j;
774
775 if (hostif->desc.bInterfaceNumber != 0)
776 return -ENODEV;
777
778 ret = usb_find_common_endpoints(hostif, &epin, &epout, NULL, NULL);
779 if (ret)
780 return ret;
781
782 dln2 = kzalloc(sizeof(*dln2), GFP_KERNEL);
783 if (!dln2)
784 return -ENOMEM;
785
786 dln2->ep_out = epout->bEndpointAddress;
787 dln2->ep_in = epin->bEndpointAddress;
788 dln2->usb_dev = usb_get_dev(interface_to_usbdev(interface));
789 dln2->interface = interface;
790 usb_set_intfdata(interface, dln2);
791 init_waitqueue_head(&dln2->disconnect_wq);
792
793 for (i = 0; i < DLN2_HANDLES; i++) {
794 init_waitqueue_head(&dln2->mod_rx_slots[i].wq);
795 spin_lock_init(&dln2->mod_rx_slots[i].lock);
796 for (j = 0; j < DLN2_MAX_RX_SLOTS; j++)
797 init_completion(&dln2->mod_rx_slots[i].slots[j].done);
798 }
799
800 spin_lock_init(&dln2->event_cb_lock);
801 spin_lock_init(&dln2->disconnect_lock);
802 INIT_LIST_HEAD(&dln2->event_cb_list);
803
804 ret = dln2_setup_rx_urbs(dln2, hostif);
805 if (ret)
806 goto out_free;
807
808 ret = dln2_start_rx_urbs(dln2, GFP_KERNEL);
809 if (ret)
810 goto out_stop_rx;
811
812 ret = dln2_hw_init(dln2);
813 if (ret < 0) {
814 dev_err(dev, "failed to initialize hardware\n");
815 goto out_stop_rx;
816 }
817
818 ret = mfd_add_hotplug_devices(dev, dln2_devs, ARRAY_SIZE(dln2_devs));
819 if (ret != 0) {
820 dev_err(dev, "failed to add mfd devices to core\n");
821 goto out_stop_rx;
822 }
823
824 return 0;
825
826out_stop_rx:
827 dln2_stop_rx_urbs(dln2);
828
829out_free:
830 dln2_free(dln2);
831
832 return ret;
833}
834
835static int dln2_suspend(struct usb_interface *iface, pm_message_t message)
836{
837 struct dln2_dev *dln2 = usb_get_intfdata(iface);
838
839 dln2_stop(dln2);
840
841 return 0;
842}
843
844static int dln2_resume(struct usb_interface *iface)
845{
846 struct dln2_dev *dln2 = usb_get_intfdata(iface);
847
848 dln2->disconnect = false;
849
850 return dln2_start_rx_urbs(dln2, GFP_NOIO);
851}
852
853static const struct usb_device_id dln2_table[] = {
854 { USB_DEVICE(0xa257, 0x2013) },
855 { }
856};
857
858MODULE_DEVICE_TABLE(usb, dln2_table);
859
860static struct usb_driver dln2_driver = {
861 .name = "dln2",
862 .probe = dln2_probe,
863 .disconnect = dln2_disconnect,
864 .id_table = dln2_table,
865 .suspend = dln2_suspend,
866 .resume = dln2_resume,
867};
868
869module_usb_driver(dln2_driver);
870
871MODULE_AUTHOR("Octavian Purdila <octavian.purdila@intel.com>");
872MODULE_DESCRIPTION("Core driver for the Diolan DLN2 interface adapter");
873MODULE_LICENSE("GPL v2");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Driver for the Diolan DLN-2 USB adapter
4 *
5 * Copyright (c) 2014 Intel Corporation
6 *
7 * Derived from:
8 * i2c-diolan-u2c.c
9 * Copyright (c) 2010-2011 Ericsson AB
10 */
11
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/types.h>
15#include <linux/slab.h>
16#include <linux/usb.h>
17#include <linux/mutex.h>
18#include <linux/platform_device.h>
19#include <linux/mfd/core.h>
20#include <linux/mfd/dln2.h>
21#include <linux/rculist.h>
22
23struct dln2_header {
24 __le16 size;
25 __le16 id;
26 __le16 echo;
27 __le16 handle;
28};
29
30struct dln2_response {
31 struct dln2_header hdr;
32 __le16 result;
33};
34
35#define DLN2_GENERIC_MODULE_ID 0x00
36#define DLN2_GENERIC_CMD(cmd) DLN2_CMD(cmd, DLN2_GENERIC_MODULE_ID)
37#define CMD_GET_DEVICE_VER DLN2_GENERIC_CMD(0x30)
38#define CMD_GET_DEVICE_SN DLN2_GENERIC_CMD(0x31)
39
40#define DLN2_HW_ID 0x200
41#define DLN2_USB_TIMEOUT 200 /* in ms */
42#define DLN2_MAX_RX_SLOTS 16
43#define DLN2_MAX_URBS 16
44#define DLN2_RX_BUF_SIZE 512
45
46enum dln2_handle {
47 DLN2_HANDLE_EVENT = 0, /* don't change, hardware defined */
48 DLN2_HANDLE_CTRL,
49 DLN2_HANDLE_GPIO,
50 DLN2_HANDLE_I2C,
51 DLN2_HANDLE_SPI,
52 DLN2_HANDLE_ADC,
53 DLN2_HANDLES
54};
55
56/*
57 * Receive context used between the receive demultiplexer and the transfer
58 * routine. While sending a request the transfer routine will look for a free
59 * receive context and use it to wait for a response and to receive the URB and
60 * thus the response data.
61 */
62struct dln2_rx_context {
63 /* completion used to wait for a response */
64 struct completion done;
65
66 /* if non-NULL the URB contains the response */
67 struct urb *urb;
68
69 /* if true then this context is used to wait for a response */
70 bool in_use;
71};
72
73/*
74 * Receive contexts for a particular DLN2 module (i2c, gpio, etc.). We use the
75 * handle header field to identify the module in dln2_dev.mod_rx_slots and then
76 * the echo header field to index the slots field and find the receive context
77 * for a particular request.
78 */
79struct dln2_mod_rx_slots {
80 /* RX slots bitmap */
81 DECLARE_BITMAP(bmap, DLN2_MAX_RX_SLOTS);
82
83 /* used to wait for a free RX slot */
84 wait_queue_head_t wq;
85
86 /* used to wait for an RX operation to complete */
87 struct dln2_rx_context slots[DLN2_MAX_RX_SLOTS];
88
89 /* avoid races between alloc/free_rx_slot and dln2_rx_transfer */
90 spinlock_t lock;
91};
92
93struct dln2_dev {
94 struct usb_device *usb_dev;
95 struct usb_interface *interface;
96 u8 ep_in;
97 u8 ep_out;
98
99 struct urb *rx_urb[DLN2_MAX_URBS];
100 void *rx_buf[DLN2_MAX_URBS];
101
102 struct dln2_mod_rx_slots mod_rx_slots[DLN2_HANDLES];
103
104 struct list_head event_cb_list;
105 spinlock_t event_cb_lock;
106
107 bool disconnect;
108 int active_transfers;
109 wait_queue_head_t disconnect_wq;
110 spinlock_t disconnect_lock;
111};
112
113struct dln2_event_cb_entry {
114 struct list_head list;
115 u16 id;
116 struct platform_device *pdev;
117 dln2_event_cb_t callback;
118};
119
120int dln2_register_event_cb(struct platform_device *pdev, u16 id,
121 dln2_event_cb_t event_cb)
122{
123 struct dln2_dev *dln2 = dev_get_drvdata(pdev->dev.parent);
124 struct dln2_event_cb_entry *i, *entry;
125 unsigned long flags;
126 int ret = 0;
127
128 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
129 if (!entry)
130 return -ENOMEM;
131
132 entry->id = id;
133 entry->callback = event_cb;
134 entry->pdev = pdev;
135
136 spin_lock_irqsave(&dln2->event_cb_lock, flags);
137
138 list_for_each_entry(i, &dln2->event_cb_list, list) {
139 if (i->id == id) {
140 ret = -EBUSY;
141 break;
142 }
143 }
144
145 if (!ret)
146 list_add_rcu(&entry->list, &dln2->event_cb_list);
147
148 spin_unlock_irqrestore(&dln2->event_cb_lock, flags);
149
150 if (ret)
151 kfree(entry);
152
153 return ret;
154}
155EXPORT_SYMBOL(dln2_register_event_cb);
156
157void dln2_unregister_event_cb(struct platform_device *pdev, u16 id)
158{
159 struct dln2_dev *dln2 = dev_get_drvdata(pdev->dev.parent);
160 struct dln2_event_cb_entry *i;
161 unsigned long flags;
162 bool found = false;
163
164 spin_lock_irqsave(&dln2->event_cb_lock, flags);
165
166 list_for_each_entry(i, &dln2->event_cb_list, list) {
167 if (i->id == id) {
168 list_del_rcu(&i->list);
169 found = true;
170 break;
171 }
172 }
173
174 spin_unlock_irqrestore(&dln2->event_cb_lock, flags);
175
176 if (found) {
177 synchronize_rcu();
178 kfree(i);
179 }
180}
181EXPORT_SYMBOL(dln2_unregister_event_cb);
182
183/*
184 * Returns true if a valid transfer slot is found. In this case the URB must not
185 * be resubmitted immediately in dln2_rx as we need the data when dln2_transfer
186 * is woke up. It will be resubmitted there.
187 */
188static bool dln2_transfer_complete(struct dln2_dev *dln2, struct urb *urb,
189 u16 handle, u16 rx_slot)
190{
191 struct device *dev = &dln2->interface->dev;
192 struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle];
193 struct dln2_rx_context *rxc;
194 unsigned long flags;
195 bool valid_slot = false;
196
197 if (rx_slot >= DLN2_MAX_RX_SLOTS)
198 goto out;
199
200 rxc = &rxs->slots[rx_slot];
201
202 spin_lock_irqsave(&rxs->lock, flags);
203 if (rxc->in_use && !rxc->urb) {
204 rxc->urb = urb;
205 complete(&rxc->done);
206 valid_slot = true;
207 }
208 spin_unlock_irqrestore(&rxs->lock, flags);
209
210out:
211 if (!valid_slot)
212 dev_warn(dev, "bad/late response %d/%d\n", handle, rx_slot);
213
214 return valid_slot;
215}
216
217static void dln2_run_event_callbacks(struct dln2_dev *dln2, u16 id, u16 echo,
218 void *data, int len)
219{
220 struct dln2_event_cb_entry *i;
221
222 rcu_read_lock();
223
224 list_for_each_entry_rcu(i, &dln2->event_cb_list, list) {
225 if (i->id == id) {
226 i->callback(i->pdev, echo, data, len);
227 break;
228 }
229 }
230
231 rcu_read_unlock();
232}
233
234static void dln2_rx(struct urb *urb)
235{
236 struct dln2_dev *dln2 = urb->context;
237 struct dln2_header *hdr = urb->transfer_buffer;
238 struct device *dev = &dln2->interface->dev;
239 u16 id, echo, handle, size;
240 u8 *data;
241 int len;
242 int err;
243
244 switch (urb->status) {
245 case 0:
246 /* success */
247 break;
248 case -ECONNRESET:
249 case -ENOENT:
250 case -ESHUTDOWN:
251 case -EPIPE:
252 /* this urb is terminated, clean up */
253 dev_dbg(dev, "urb shutting down with status %d\n", urb->status);
254 return;
255 default:
256 dev_dbg(dev, "nonzero urb status received %d\n", urb->status);
257 goto out;
258 }
259
260 if (urb->actual_length < sizeof(struct dln2_header)) {
261 dev_err(dev, "short response: %d\n", urb->actual_length);
262 goto out;
263 }
264
265 handle = le16_to_cpu(hdr->handle);
266 id = le16_to_cpu(hdr->id);
267 echo = le16_to_cpu(hdr->echo);
268 size = le16_to_cpu(hdr->size);
269
270 if (size != urb->actual_length) {
271 dev_err(dev, "size mismatch: handle %x cmd %x echo %x size %d actual %d\n",
272 handle, id, echo, size, urb->actual_length);
273 goto out;
274 }
275
276 if (handle >= DLN2_HANDLES) {
277 dev_warn(dev, "invalid handle %d\n", handle);
278 goto out;
279 }
280
281 data = urb->transfer_buffer + sizeof(struct dln2_header);
282 len = urb->actual_length - sizeof(struct dln2_header);
283
284 if (handle == DLN2_HANDLE_EVENT) {
285 unsigned long flags;
286
287 spin_lock_irqsave(&dln2->event_cb_lock, flags);
288 dln2_run_event_callbacks(dln2, id, echo, data, len);
289 spin_unlock_irqrestore(&dln2->event_cb_lock, flags);
290 } else {
291 /* URB will be re-submitted in _dln2_transfer (free_rx_slot) */
292 if (dln2_transfer_complete(dln2, urb, handle, echo))
293 return;
294 }
295
296out:
297 err = usb_submit_urb(urb, GFP_ATOMIC);
298 if (err < 0)
299 dev_err(dev, "failed to resubmit RX URB: %d\n", err);
300}
301
302static void *dln2_prep_buf(u16 handle, u16 cmd, u16 echo, const void *obuf,
303 int *obuf_len, gfp_t gfp)
304{
305 int len;
306 void *buf;
307 struct dln2_header *hdr;
308
309 len = *obuf_len + sizeof(*hdr);
310 buf = kmalloc(len, gfp);
311 if (!buf)
312 return NULL;
313
314 hdr = (struct dln2_header *)buf;
315 hdr->id = cpu_to_le16(cmd);
316 hdr->size = cpu_to_le16(len);
317 hdr->echo = cpu_to_le16(echo);
318 hdr->handle = cpu_to_le16(handle);
319
320 memcpy(buf + sizeof(*hdr), obuf, *obuf_len);
321
322 *obuf_len = len;
323
324 return buf;
325}
326
327static int dln2_send_wait(struct dln2_dev *dln2, u16 handle, u16 cmd, u16 echo,
328 const void *obuf, int obuf_len)
329{
330 int ret = 0;
331 int len = obuf_len;
332 void *buf;
333 int actual;
334
335 buf = dln2_prep_buf(handle, cmd, echo, obuf, &len, GFP_KERNEL);
336 if (!buf)
337 return -ENOMEM;
338
339 ret = usb_bulk_msg(dln2->usb_dev,
340 usb_sndbulkpipe(dln2->usb_dev, dln2->ep_out),
341 buf, len, &actual, DLN2_USB_TIMEOUT);
342
343 kfree(buf);
344
345 return ret;
346}
347
348static bool find_free_slot(struct dln2_dev *dln2, u16 handle, int *slot)
349{
350 struct dln2_mod_rx_slots *rxs;
351 unsigned long flags;
352
353 if (dln2->disconnect) {
354 *slot = -ENODEV;
355 return true;
356 }
357
358 rxs = &dln2->mod_rx_slots[handle];
359
360 spin_lock_irqsave(&rxs->lock, flags);
361
362 *slot = find_first_zero_bit(rxs->bmap, DLN2_MAX_RX_SLOTS);
363
364 if (*slot < DLN2_MAX_RX_SLOTS) {
365 struct dln2_rx_context *rxc = &rxs->slots[*slot];
366
367 set_bit(*slot, rxs->bmap);
368 rxc->in_use = true;
369 }
370
371 spin_unlock_irqrestore(&rxs->lock, flags);
372
373 return *slot < DLN2_MAX_RX_SLOTS;
374}
375
376static int alloc_rx_slot(struct dln2_dev *dln2, u16 handle)
377{
378 int ret;
379 int slot;
380
381 /*
382 * No need to timeout here, the wait is bounded by the timeout in
383 * _dln2_transfer.
384 */
385 ret = wait_event_interruptible(dln2->mod_rx_slots[handle].wq,
386 find_free_slot(dln2, handle, &slot));
387 if (ret < 0)
388 return ret;
389
390 return slot;
391}
392
393static void free_rx_slot(struct dln2_dev *dln2, u16 handle, int slot)
394{
395 struct dln2_mod_rx_slots *rxs;
396 struct urb *urb = NULL;
397 unsigned long flags;
398 struct dln2_rx_context *rxc;
399
400 rxs = &dln2->mod_rx_slots[handle];
401
402 spin_lock_irqsave(&rxs->lock, flags);
403
404 clear_bit(slot, rxs->bmap);
405
406 rxc = &rxs->slots[slot];
407 rxc->in_use = false;
408 urb = rxc->urb;
409 rxc->urb = NULL;
410 reinit_completion(&rxc->done);
411
412 spin_unlock_irqrestore(&rxs->lock, flags);
413
414 if (urb) {
415 int err;
416 struct device *dev = &dln2->interface->dev;
417
418 err = usb_submit_urb(urb, GFP_KERNEL);
419 if (err < 0)
420 dev_err(dev, "failed to resubmit RX URB: %d\n", err);
421 }
422
423 wake_up_interruptible(&rxs->wq);
424}
425
426static int _dln2_transfer(struct dln2_dev *dln2, u16 handle, u16 cmd,
427 const void *obuf, unsigned obuf_len,
428 void *ibuf, unsigned *ibuf_len)
429{
430 int ret = 0;
431 int rx_slot;
432 struct dln2_response *rsp;
433 struct dln2_rx_context *rxc;
434 struct device *dev = &dln2->interface->dev;
435 const unsigned long timeout = msecs_to_jiffies(DLN2_USB_TIMEOUT);
436 struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle];
437 int size;
438
439 spin_lock(&dln2->disconnect_lock);
440 if (!dln2->disconnect)
441 dln2->active_transfers++;
442 else
443 ret = -ENODEV;
444 spin_unlock(&dln2->disconnect_lock);
445
446 if (ret)
447 return ret;
448
449 rx_slot = alloc_rx_slot(dln2, handle);
450 if (rx_slot < 0) {
451 ret = rx_slot;
452 goto out_decr;
453 }
454
455 ret = dln2_send_wait(dln2, handle, cmd, rx_slot, obuf, obuf_len);
456 if (ret < 0) {
457 dev_err(dev, "USB write failed: %d\n", ret);
458 goto out_free_rx_slot;
459 }
460
461 rxc = &rxs->slots[rx_slot];
462
463 ret = wait_for_completion_interruptible_timeout(&rxc->done, timeout);
464 if (ret <= 0) {
465 if (!ret)
466 ret = -ETIMEDOUT;
467 goto out_free_rx_slot;
468 } else {
469 ret = 0;
470 }
471
472 if (dln2->disconnect) {
473 ret = -ENODEV;
474 goto out_free_rx_slot;
475 }
476
477 /* if we got here we know that the response header has been checked */
478 rsp = rxc->urb->transfer_buffer;
479 size = le16_to_cpu(rsp->hdr.size);
480
481 if (size < sizeof(*rsp)) {
482 ret = -EPROTO;
483 goto out_free_rx_slot;
484 }
485
486 if (le16_to_cpu(rsp->result) > 0x80) {
487 dev_dbg(dev, "%d received response with error %d\n",
488 handle, le16_to_cpu(rsp->result));
489 ret = -EREMOTEIO;
490 goto out_free_rx_slot;
491 }
492
493 if (!ibuf)
494 goto out_free_rx_slot;
495
496 if (*ibuf_len > size - sizeof(*rsp))
497 *ibuf_len = size - sizeof(*rsp);
498
499 memcpy(ibuf, rsp + 1, *ibuf_len);
500
501out_free_rx_slot:
502 free_rx_slot(dln2, handle, rx_slot);
503out_decr:
504 spin_lock(&dln2->disconnect_lock);
505 dln2->active_transfers--;
506 spin_unlock(&dln2->disconnect_lock);
507 if (dln2->disconnect)
508 wake_up(&dln2->disconnect_wq);
509
510 return ret;
511}
512
513int dln2_transfer(struct platform_device *pdev, u16 cmd,
514 const void *obuf, unsigned obuf_len,
515 void *ibuf, unsigned *ibuf_len)
516{
517 struct dln2_platform_data *dln2_pdata;
518 struct dln2_dev *dln2;
519 u16 handle;
520
521 dln2 = dev_get_drvdata(pdev->dev.parent);
522 dln2_pdata = dev_get_platdata(&pdev->dev);
523 handle = dln2_pdata->handle;
524
525 return _dln2_transfer(dln2, handle, cmd, obuf, obuf_len, ibuf,
526 ibuf_len);
527}
528EXPORT_SYMBOL(dln2_transfer);
529
530static int dln2_check_hw(struct dln2_dev *dln2)
531{
532 int ret;
533 __le32 hw_type;
534 int len = sizeof(hw_type);
535
536 ret = _dln2_transfer(dln2, DLN2_HANDLE_CTRL, CMD_GET_DEVICE_VER,
537 NULL, 0, &hw_type, &len);
538 if (ret < 0)
539 return ret;
540 if (len < sizeof(hw_type))
541 return -EREMOTEIO;
542
543 if (le32_to_cpu(hw_type) != DLN2_HW_ID) {
544 dev_err(&dln2->interface->dev, "Device ID 0x%x not supported\n",
545 le32_to_cpu(hw_type));
546 return -ENODEV;
547 }
548
549 return 0;
550}
551
552static int dln2_print_serialno(struct dln2_dev *dln2)
553{
554 int ret;
555 __le32 serial_no;
556 int len = sizeof(serial_no);
557 struct device *dev = &dln2->interface->dev;
558
559 ret = _dln2_transfer(dln2, DLN2_HANDLE_CTRL, CMD_GET_DEVICE_SN, NULL, 0,
560 &serial_no, &len);
561 if (ret < 0)
562 return ret;
563 if (len < sizeof(serial_no))
564 return -EREMOTEIO;
565
566 dev_info(dev, "Diolan DLN2 serial %u\n", le32_to_cpu(serial_no));
567
568 return 0;
569}
570
571static int dln2_hw_init(struct dln2_dev *dln2)
572{
573 int ret;
574
575 ret = dln2_check_hw(dln2);
576 if (ret < 0)
577 return ret;
578
579 return dln2_print_serialno(dln2);
580}
581
582static void dln2_free_rx_urbs(struct dln2_dev *dln2)
583{
584 int i;
585
586 for (i = 0; i < DLN2_MAX_URBS; i++) {
587 usb_free_urb(dln2->rx_urb[i]);
588 kfree(dln2->rx_buf[i]);
589 }
590}
591
592static void dln2_stop_rx_urbs(struct dln2_dev *dln2)
593{
594 int i;
595
596 for (i = 0; i < DLN2_MAX_URBS; i++)
597 usb_kill_urb(dln2->rx_urb[i]);
598}
599
600static void dln2_free(struct dln2_dev *dln2)
601{
602 dln2_free_rx_urbs(dln2);
603 usb_put_dev(dln2->usb_dev);
604 kfree(dln2);
605}
606
607static int dln2_setup_rx_urbs(struct dln2_dev *dln2,
608 struct usb_host_interface *hostif)
609{
610 int i;
611 const int rx_max_size = DLN2_RX_BUF_SIZE;
612
613 for (i = 0; i < DLN2_MAX_URBS; i++) {
614 dln2->rx_buf[i] = kmalloc(rx_max_size, GFP_KERNEL);
615 if (!dln2->rx_buf[i])
616 return -ENOMEM;
617
618 dln2->rx_urb[i] = usb_alloc_urb(0, GFP_KERNEL);
619 if (!dln2->rx_urb[i])
620 return -ENOMEM;
621
622 usb_fill_bulk_urb(dln2->rx_urb[i], dln2->usb_dev,
623 usb_rcvbulkpipe(dln2->usb_dev, dln2->ep_in),
624 dln2->rx_buf[i], rx_max_size, dln2_rx, dln2);
625 }
626
627 return 0;
628}
629
630static int dln2_start_rx_urbs(struct dln2_dev *dln2, gfp_t gfp)
631{
632 struct device *dev = &dln2->interface->dev;
633 int ret;
634 int i;
635
636 for (i = 0; i < DLN2_MAX_URBS; i++) {
637 ret = usb_submit_urb(dln2->rx_urb[i], gfp);
638 if (ret < 0) {
639 dev_err(dev, "failed to submit RX URB: %d\n", ret);
640 return ret;
641 }
642 }
643
644 return 0;
645}
646
647enum {
648 DLN2_ACPI_MATCH_GPIO = 0,
649 DLN2_ACPI_MATCH_I2C = 1,
650 DLN2_ACPI_MATCH_SPI = 2,
651 DLN2_ACPI_MATCH_ADC = 3,
652};
653
654static struct dln2_platform_data dln2_pdata_gpio = {
655 .handle = DLN2_HANDLE_GPIO,
656};
657
658static struct mfd_cell_acpi_match dln2_acpi_match_gpio = {
659 .adr = DLN2_ACPI_MATCH_GPIO,
660};
661
662/* Only one I2C port seems to be supported on current hardware */
663static struct dln2_platform_data dln2_pdata_i2c = {
664 .handle = DLN2_HANDLE_I2C,
665 .port = 0,
666};
667
668static struct mfd_cell_acpi_match dln2_acpi_match_i2c = {
669 .adr = DLN2_ACPI_MATCH_I2C,
670};
671
672/* Only one SPI port supported */
673static struct dln2_platform_data dln2_pdata_spi = {
674 .handle = DLN2_HANDLE_SPI,
675 .port = 0,
676};
677
678static struct mfd_cell_acpi_match dln2_acpi_match_spi = {
679 .adr = DLN2_ACPI_MATCH_SPI,
680};
681
682/* Only one ADC port supported */
683static struct dln2_platform_data dln2_pdata_adc = {
684 .handle = DLN2_HANDLE_ADC,
685 .port = 0,
686};
687
688static struct mfd_cell_acpi_match dln2_acpi_match_adc = {
689 .adr = DLN2_ACPI_MATCH_ADC,
690};
691
692static const struct mfd_cell dln2_devs[] = {
693 {
694 .name = "dln2-gpio",
695 .acpi_match = &dln2_acpi_match_gpio,
696 .platform_data = &dln2_pdata_gpio,
697 .pdata_size = sizeof(struct dln2_platform_data),
698 },
699 {
700 .name = "dln2-i2c",
701 .acpi_match = &dln2_acpi_match_i2c,
702 .platform_data = &dln2_pdata_i2c,
703 .pdata_size = sizeof(struct dln2_platform_data),
704 },
705 {
706 .name = "dln2-spi",
707 .acpi_match = &dln2_acpi_match_spi,
708 .platform_data = &dln2_pdata_spi,
709 .pdata_size = sizeof(struct dln2_platform_data),
710 },
711 {
712 .name = "dln2-adc",
713 .acpi_match = &dln2_acpi_match_adc,
714 .platform_data = &dln2_pdata_adc,
715 .pdata_size = sizeof(struct dln2_platform_data),
716 },
717};
718
719static void dln2_stop(struct dln2_dev *dln2)
720{
721 int i, j;
722
723 /* don't allow starting new transfers */
724 spin_lock(&dln2->disconnect_lock);
725 dln2->disconnect = true;
726 spin_unlock(&dln2->disconnect_lock);
727
728 /* cancel in progress transfers */
729 for (i = 0; i < DLN2_HANDLES; i++) {
730 struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[i];
731 unsigned long flags;
732
733 spin_lock_irqsave(&rxs->lock, flags);
734
735 /* cancel all response waiters */
736 for (j = 0; j < DLN2_MAX_RX_SLOTS; j++) {
737 struct dln2_rx_context *rxc = &rxs->slots[j];
738
739 if (rxc->in_use)
740 complete(&rxc->done);
741 }
742
743 spin_unlock_irqrestore(&rxs->lock, flags);
744 }
745
746 /* wait for transfers to end */
747 wait_event(dln2->disconnect_wq, !dln2->active_transfers);
748
749 dln2_stop_rx_urbs(dln2);
750}
751
752static void dln2_disconnect(struct usb_interface *interface)
753{
754 struct dln2_dev *dln2 = usb_get_intfdata(interface);
755
756 dln2_stop(dln2);
757
758 mfd_remove_devices(&interface->dev);
759
760 dln2_free(dln2);
761}
762
763static int dln2_probe(struct usb_interface *interface,
764 const struct usb_device_id *usb_id)
765{
766 struct usb_host_interface *hostif = interface->cur_altsetting;
767 struct usb_endpoint_descriptor *epin;
768 struct usb_endpoint_descriptor *epout;
769 struct device *dev = &interface->dev;
770 struct dln2_dev *dln2;
771 int ret;
772 int i, j;
773
774 if (hostif->desc.bInterfaceNumber != 0)
775 return -ENODEV;
776
777 ret = usb_find_common_endpoints(hostif, &epin, &epout, NULL, NULL);
778 if (ret)
779 return ret;
780
781 dln2 = kzalloc(sizeof(*dln2), GFP_KERNEL);
782 if (!dln2)
783 return -ENOMEM;
784
785 dln2->ep_out = epout->bEndpointAddress;
786 dln2->ep_in = epin->bEndpointAddress;
787 dln2->usb_dev = usb_get_dev(interface_to_usbdev(interface));
788 dln2->interface = interface;
789 usb_set_intfdata(interface, dln2);
790 init_waitqueue_head(&dln2->disconnect_wq);
791
792 for (i = 0; i < DLN2_HANDLES; i++) {
793 init_waitqueue_head(&dln2->mod_rx_slots[i].wq);
794 spin_lock_init(&dln2->mod_rx_slots[i].lock);
795 for (j = 0; j < DLN2_MAX_RX_SLOTS; j++)
796 init_completion(&dln2->mod_rx_slots[i].slots[j].done);
797 }
798
799 spin_lock_init(&dln2->event_cb_lock);
800 spin_lock_init(&dln2->disconnect_lock);
801 INIT_LIST_HEAD(&dln2->event_cb_list);
802
803 ret = dln2_setup_rx_urbs(dln2, hostif);
804 if (ret)
805 goto out_free;
806
807 ret = dln2_start_rx_urbs(dln2, GFP_KERNEL);
808 if (ret)
809 goto out_stop_rx;
810
811 ret = dln2_hw_init(dln2);
812 if (ret < 0) {
813 dev_err(dev, "failed to initialize hardware\n");
814 goto out_stop_rx;
815 }
816
817 ret = mfd_add_hotplug_devices(dev, dln2_devs, ARRAY_SIZE(dln2_devs));
818 if (ret != 0) {
819 dev_err(dev, "failed to add mfd devices to core\n");
820 goto out_stop_rx;
821 }
822
823 return 0;
824
825out_stop_rx:
826 dln2_stop_rx_urbs(dln2);
827
828out_free:
829 dln2_free(dln2);
830
831 return ret;
832}
833
834static int dln2_suspend(struct usb_interface *iface, pm_message_t message)
835{
836 struct dln2_dev *dln2 = usb_get_intfdata(iface);
837
838 dln2_stop(dln2);
839
840 return 0;
841}
842
843static int dln2_resume(struct usb_interface *iface)
844{
845 struct dln2_dev *dln2 = usb_get_intfdata(iface);
846
847 dln2->disconnect = false;
848
849 return dln2_start_rx_urbs(dln2, GFP_NOIO);
850}
851
852static const struct usb_device_id dln2_table[] = {
853 { USB_DEVICE(0xa257, 0x2013) },
854 { }
855};
856
857MODULE_DEVICE_TABLE(usb, dln2_table);
858
859static struct usb_driver dln2_driver = {
860 .name = "dln2",
861 .probe = dln2_probe,
862 .disconnect = dln2_disconnect,
863 .id_table = dln2_table,
864 .suspend = dln2_suspend,
865 .resume = dln2_resume,
866};
867
868module_usb_driver(dln2_driver);
869
870MODULE_AUTHOR("Octavian Purdila <octavian.purdila@intel.com>");
871MODULE_DESCRIPTION("Core driver for the Diolan DLN2 interface adapter");
872MODULE_LICENSE("GPL v2");