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v5.9
  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_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
 93enum dln2_endpoint {
 94	DLN2_EP_OUT	= 0,
 95	DLN2_EP_IN	= 1,
 96};
 97
 98struct dln2_dev {
 99	struct usb_device *usb_dev;
100	struct usb_interface *interface;
101	u8 ep_in;
102	u8 ep_out;
103
104	struct urb *rx_urb[DLN2_MAX_URBS];
105	void *rx_buf[DLN2_MAX_URBS];
106
107	struct dln2_mod_rx_slots mod_rx_slots[DLN2_HANDLES];
108
109	struct list_head event_cb_list;
110	spinlock_t event_cb_lock;
111
112	bool disconnect;
113	int active_transfers;
114	wait_queue_head_t disconnect_wq;
115	spinlock_t disconnect_lock;
116};
117
118struct dln2_event_cb_entry {
119	struct list_head list;
120	u16 id;
121	struct platform_device *pdev;
122	dln2_event_cb_t callback;
123};
124
125int dln2_register_event_cb(struct platform_device *pdev, u16 id,
126			   dln2_event_cb_t event_cb)
127{
128	struct dln2_dev *dln2 = dev_get_drvdata(pdev->dev.parent);
129	struct dln2_event_cb_entry *i, *entry;
130	unsigned long flags;
131	int ret = 0;
132
133	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
134	if (!entry)
135		return -ENOMEM;
136
137	entry->id = id;
138	entry->callback = event_cb;
139	entry->pdev = pdev;
140
141	spin_lock_irqsave(&dln2->event_cb_lock, flags);
142
143	list_for_each_entry(i, &dln2->event_cb_list, list) {
144		if (i->id == id) {
145			ret = -EBUSY;
146			break;
147		}
148	}
149
150	if (!ret)
151		list_add_rcu(&entry->list, &dln2->event_cb_list);
152
153	spin_unlock_irqrestore(&dln2->event_cb_lock, flags);
154
155	if (ret)
156		kfree(entry);
157
158	return ret;
159}
160EXPORT_SYMBOL(dln2_register_event_cb);
161
162void dln2_unregister_event_cb(struct platform_device *pdev, u16 id)
163{
164	struct dln2_dev *dln2 = dev_get_drvdata(pdev->dev.parent);
165	struct dln2_event_cb_entry *i;
166	unsigned long flags;
167	bool found = false;
168
169	spin_lock_irqsave(&dln2->event_cb_lock, flags);
170
171	list_for_each_entry(i, &dln2->event_cb_list, list) {
172		if (i->id == id) {
173			list_del_rcu(&i->list);
174			found = true;
175			break;
176		}
177	}
178
179	spin_unlock_irqrestore(&dln2->event_cb_lock, flags);
180
181	if (found) {
182		synchronize_rcu();
183		kfree(i);
184	}
185}
186EXPORT_SYMBOL(dln2_unregister_event_cb);
187
188/*
189 * Returns true if a valid transfer slot is found. In this case the URB must not
190 * be resubmitted immediately in dln2_rx as we need the data when dln2_transfer
191 * is woke up. It will be resubmitted there.
192 */
193static bool dln2_transfer_complete(struct dln2_dev *dln2, struct urb *urb,
194				   u16 handle, u16 rx_slot)
195{
196	struct device *dev = &dln2->interface->dev;
197	struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle];
198	struct dln2_rx_context *rxc;
199	unsigned long flags;
200	bool valid_slot = false;
201
202	if (rx_slot >= DLN2_MAX_RX_SLOTS)
203		goto out;
204
205	rxc = &rxs->slots[rx_slot];
206
207	spin_lock_irqsave(&rxs->lock, flags);
208	if (rxc->in_use && !rxc->urb) {
209		rxc->urb = urb;
210		complete(&rxc->done);
211		valid_slot = true;
212	}
213	spin_unlock_irqrestore(&rxs->lock, flags);
214
215out:
216	if (!valid_slot)
217		dev_warn(dev, "bad/late response %d/%d\n", handle, rx_slot);
218
219	return valid_slot;
220}
221
222static void dln2_run_event_callbacks(struct dln2_dev *dln2, u16 id, u16 echo,
223				     void *data, int len)
224{
225	struct dln2_event_cb_entry *i;
226
227	rcu_read_lock();
228
229	list_for_each_entry_rcu(i, &dln2->event_cb_list, list) {
230		if (i->id == id) {
231			i->callback(i->pdev, echo, data, len);
232			break;
233		}
234	}
235
236	rcu_read_unlock();
237}
238
239static void dln2_rx(struct urb *urb)
240{
241	struct dln2_dev *dln2 = urb->context;
242	struct dln2_header *hdr = urb->transfer_buffer;
243	struct device *dev = &dln2->interface->dev;
244	u16 id, echo, handle, size;
245	u8 *data;
246	int len;
247	int err;
248
249	switch (urb->status) {
250	case 0:
251		/* success */
252		break;
253	case -ECONNRESET:
254	case -ENOENT:
255	case -ESHUTDOWN:
256	case -EPIPE:
257		/* this urb is terminated, clean up */
258		dev_dbg(dev, "urb shutting down with status %d\n", urb->status);
259		return;
260	default:
261		dev_dbg(dev, "nonzero urb status received %d\n", urb->status);
262		goto out;
263	}
264
265	if (urb->actual_length < sizeof(struct dln2_header)) {
266		dev_err(dev, "short response: %d\n", urb->actual_length);
267		goto out;
268	}
269
270	handle = le16_to_cpu(hdr->handle);
271	id = le16_to_cpu(hdr->id);
272	echo = le16_to_cpu(hdr->echo);
273	size = le16_to_cpu(hdr->size);
274
275	if (size != urb->actual_length) {
276		dev_err(dev, "size mismatch: handle %x cmd %x echo %x size %d actual %d\n",
277			handle, id, echo, size, urb->actual_length);
278		goto out;
279	}
280
281	if (handle >= DLN2_HANDLES) {
282		dev_warn(dev, "invalid handle %d\n", handle);
283		goto out;
284	}
285
286	data = urb->transfer_buffer + sizeof(struct dln2_header);
287	len = urb->actual_length - sizeof(struct dln2_header);
288
289	if (handle == DLN2_HANDLE_EVENT) {
290		unsigned long flags;
291
292		spin_lock_irqsave(&dln2->event_cb_lock, flags);
293		dln2_run_event_callbacks(dln2, id, echo, data, len);
294		spin_unlock_irqrestore(&dln2->event_cb_lock, flags);
295	} else {
296		/* URB will be re-submitted in _dln2_transfer (free_rx_slot) */
297		if (dln2_transfer_complete(dln2, urb, handle, echo))
298			return;
299	}
300
301out:
302	err = usb_submit_urb(urb, GFP_ATOMIC);
303	if (err < 0)
304		dev_err(dev, "failed to resubmit RX URB: %d\n", err);
305}
306
307static void *dln2_prep_buf(u16 handle, u16 cmd, u16 echo, const void *obuf,
308			   int *obuf_len, gfp_t gfp)
309{
310	int len;
311	void *buf;
312	struct dln2_header *hdr;
313
314	len = *obuf_len + sizeof(*hdr);
315	buf = kmalloc(len, gfp);
316	if (!buf)
317		return NULL;
318
319	hdr = (struct dln2_header *)buf;
320	hdr->id = cpu_to_le16(cmd);
321	hdr->size = cpu_to_le16(len);
322	hdr->echo = cpu_to_le16(echo);
323	hdr->handle = cpu_to_le16(handle);
324
325	memcpy(buf + sizeof(*hdr), obuf, *obuf_len);
326
327	*obuf_len = len;
328
329	return buf;
330}
331
332static int dln2_send_wait(struct dln2_dev *dln2, u16 handle, u16 cmd, u16 echo,
333			  const void *obuf, int obuf_len)
334{
335	int ret = 0;
336	int len = obuf_len;
337	void *buf;
338	int actual;
339
340	buf = dln2_prep_buf(handle, cmd, echo, obuf, &len, GFP_KERNEL);
341	if (!buf)
342		return -ENOMEM;
343
344	ret = usb_bulk_msg(dln2->usb_dev,
345			   usb_sndbulkpipe(dln2->usb_dev, dln2->ep_out),
346			   buf, len, &actual, DLN2_USB_TIMEOUT);
347
348	kfree(buf);
349
350	return ret;
351}
352
353static bool find_free_slot(struct dln2_dev *dln2, u16 handle, int *slot)
354{
355	struct dln2_mod_rx_slots *rxs;
356	unsigned long flags;
357
358	if (dln2->disconnect) {
359		*slot = -ENODEV;
360		return true;
361	}
362
363	rxs = &dln2->mod_rx_slots[handle];
364
365	spin_lock_irqsave(&rxs->lock, flags);
366
367	*slot = find_first_zero_bit(rxs->bmap, DLN2_MAX_RX_SLOTS);
368
369	if (*slot < DLN2_MAX_RX_SLOTS) {
370		struct dln2_rx_context *rxc = &rxs->slots[*slot];
371
372		set_bit(*slot, rxs->bmap);
373		rxc->in_use = true;
374	}
375
376	spin_unlock_irqrestore(&rxs->lock, flags);
377
378	return *slot < DLN2_MAX_RX_SLOTS;
379}
380
381static int alloc_rx_slot(struct dln2_dev *dln2, u16 handle)
382{
383	int ret;
384	int slot;
385
386	/*
387	 * No need to timeout here, the wait is bounded by the timeout in
388	 * _dln2_transfer.
389	 */
390	ret = wait_event_interruptible(dln2->mod_rx_slots[handle].wq,
391				       find_free_slot(dln2, handle, &slot));
392	if (ret < 0)
393		return ret;
394
395	return slot;
396}
397
398static void free_rx_slot(struct dln2_dev *dln2, u16 handle, int slot)
399{
400	struct dln2_mod_rx_slots *rxs;
401	struct urb *urb = NULL;
402	unsigned long flags;
403	struct dln2_rx_context *rxc;
404
405	rxs = &dln2->mod_rx_slots[handle];
406
407	spin_lock_irqsave(&rxs->lock, flags);
408
409	clear_bit(slot, rxs->bmap);
410
411	rxc = &rxs->slots[slot];
412	rxc->in_use = false;
413	urb = rxc->urb;
414	rxc->urb = NULL;
415	reinit_completion(&rxc->done);
416
417	spin_unlock_irqrestore(&rxs->lock, flags);
418
419	if (urb) {
420		int err;
421		struct device *dev = &dln2->interface->dev;
422
423		err = usb_submit_urb(urb, GFP_KERNEL);
424		if (err < 0)
425			dev_err(dev, "failed to resubmit RX URB: %d\n", err);
426	}
427
428	wake_up_interruptible(&rxs->wq);
429}
430
431static int _dln2_transfer(struct dln2_dev *dln2, u16 handle, u16 cmd,
432			  const void *obuf, unsigned obuf_len,
433			  void *ibuf, unsigned *ibuf_len)
434{
435	int ret = 0;
436	int rx_slot;
437	struct dln2_response *rsp;
438	struct dln2_rx_context *rxc;
439	struct device *dev = &dln2->interface->dev;
440	const unsigned long timeout = msecs_to_jiffies(DLN2_USB_TIMEOUT);
441	struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle];
442	int size;
443
444	spin_lock(&dln2->disconnect_lock);
445	if (!dln2->disconnect)
446		dln2->active_transfers++;
447	else
448		ret = -ENODEV;
449	spin_unlock(&dln2->disconnect_lock);
450
451	if (ret)
452		return ret;
453
454	rx_slot = alloc_rx_slot(dln2, handle);
455	if (rx_slot < 0) {
456		ret = rx_slot;
457		goto out_decr;
458	}
459
460	ret = dln2_send_wait(dln2, handle, cmd, rx_slot, obuf, obuf_len);
461	if (ret < 0) {
462		dev_err(dev, "USB write failed: %d\n", ret);
463		goto out_free_rx_slot;
464	}
465
466	rxc = &rxs->slots[rx_slot];
467
468	ret = wait_for_completion_interruptible_timeout(&rxc->done, timeout);
469	if (ret <= 0) {
470		if (!ret)
471			ret = -ETIMEDOUT;
472		goto out_free_rx_slot;
473	} else {
474		ret = 0;
475	}
476
477	if (dln2->disconnect) {
478		ret = -ENODEV;
479		goto out_free_rx_slot;
480	}
481
482	/* if we got here we know that the response header has been checked */
483	rsp = rxc->urb->transfer_buffer;
484	size = le16_to_cpu(rsp->hdr.size);
485
486	if (size < sizeof(*rsp)) {
487		ret = -EPROTO;
488		goto out_free_rx_slot;
489	}
490
491	if (le16_to_cpu(rsp->result) > 0x80) {
492		dev_dbg(dev, "%d received response with error %d\n",
493			handle, le16_to_cpu(rsp->result));
494		ret = -EREMOTEIO;
495		goto out_free_rx_slot;
496	}
497
498	if (!ibuf)
499		goto out_free_rx_slot;
500
501	if (*ibuf_len > size - sizeof(*rsp))
502		*ibuf_len = size - sizeof(*rsp);
503
504	memcpy(ibuf, rsp + 1, *ibuf_len);
505
506out_free_rx_slot:
507	free_rx_slot(dln2, handle, rx_slot);
508out_decr:
509	spin_lock(&dln2->disconnect_lock);
510	dln2->active_transfers--;
511	spin_unlock(&dln2->disconnect_lock);
512	if (dln2->disconnect)
513		wake_up(&dln2->disconnect_wq);
514
515	return ret;
516}
517
518int dln2_transfer(struct platform_device *pdev, u16 cmd,
519		  const void *obuf, unsigned obuf_len,
520		  void *ibuf, unsigned *ibuf_len)
521{
522	struct dln2_platform_data *dln2_pdata;
523	struct dln2_dev *dln2;
524	u16 handle;
525
526	dln2 = dev_get_drvdata(pdev->dev.parent);
527	dln2_pdata = dev_get_platdata(&pdev->dev);
528	handle = dln2_pdata->handle;
529
530	return _dln2_transfer(dln2, handle, cmd, obuf, obuf_len, ibuf,
531			      ibuf_len);
532}
533EXPORT_SYMBOL(dln2_transfer);
534
535static int dln2_check_hw(struct dln2_dev *dln2)
536{
537	int ret;
538	__le32 hw_type;
539	int len = sizeof(hw_type);
540
541	ret = _dln2_transfer(dln2, DLN2_HANDLE_CTRL, CMD_GET_DEVICE_VER,
542			     NULL, 0, &hw_type, &len);
543	if (ret < 0)
544		return ret;
545	if (len < sizeof(hw_type))
546		return -EREMOTEIO;
547
548	if (le32_to_cpu(hw_type) != DLN2_HW_ID) {
549		dev_err(&dln2->interface->dev, "Device ID 0x%x not supported\n",
550			le32_to_cpu(hw_type));
551		return -ENODEV;
552	}
553
554	return 0;
555}
556
557static int dln2_print_serialno(struct dln2_dev *dln2)
558{
559	int ret;
560	__le32 serial_no;
561	int len = sizeof(serial_no);
562	struct device *dev = &dln2->interface->dev;
563
564	ret = _dln2_transfer(dln2, DLN2_HANDLE_CTRL, CMD_GET_DEVICE_SN, NULL, 0,
565			     &serial_no, &len);
566	if (ret < 0)
567		return ret;
568	if (len < sizeof(serial_no))
569		return -EREMOTEIO;
570
571	dev_info(dev, "Diolan DLN2 serial %u\n", le32_to_cpu(serial_no));
572
573	return 0;
574}
575
576static int dln2_hw_init(struct dln2_dev *dln2)
577{
578	int ret;
579
580	ret = dln2_check_hw(dln2);
581	if (ret < 0)
582		return ret;
583
584	return dln2_print_serialno(dln2);
585}
586
587static void dln2_free_rx_urbs(struct dln2_dev *dln2)
588{
589	int i;
590
591	for (i = 0; i < DLN2_MAX_URBS; i++) {
592		usb_free_urb(dln2->rx_urb[i]);
593		kfree(dln2->rx_buf[i]);
594	}
595}
596
597static void dln2_stop_rx_urbs(struct dln2_dev *dln2)
598{
599	int i;
600
601	for (i = 0; i < DLN2_MAX_URBS; i++)
602		usb_kill_urb(dln2->rx_urb[i]);
603}
604
605static void dln2_free(struct dln2_dev *dln2)
606{
607	dln2_free_rx_urbs(dln2);
608	usb_put_dev(dln2->usb_dev);
609	kfree(dln2);
610}
611
612static int dln2_setup_rx_urbs(struct dln2_dev *dln2,
613			      struct usb_host_interface *hostif)
614{
615	int i;
616	const int rx_max_size = DLN2_RX_BUF_SIZE;
617
618	for (i = 0; i < DLN2_MAX_URBS; i++) {
619		dln2->rx_buf[i] = kmalloc(rx_max_size, GFP_KERNEL);
620		if (!dln2->rx_buf[i])
621			return -ENOMEM;
622
623		dln2->rx_urb[i] = usb_alloc_urb(0, GFP_KERNEL);
624		if (!dln2->rx_urb[i])
625			return -ENOMEM;
626
627		usb_fill_bulk_urb(dln2->rx_urb[i], dln2->usb_dev,
628				  usb_rcvbulkpipe(dln2->usb_dev, dln2->ep_in),
629				  dln2->rx_buf[i], rx_max_size, dln2_rx, dln2);
630	}
631
632	return 0;
633}
634
635static int dln2_start_rx_urbs(struct dln2_dev *dln2, gfp_t gfp)
636{
637	struct device *dev = &dln2->interface->dev;
638	int ret;
639	int i;
640
641	for (i = 0; i < DLN2_MAX_URBS; i++) {
642		ret = usb_submit_urb(dln2->rx_urb[i], gfp);
643		if (ret < 0) {
644			dev_err(dev, "failed to submit RX URB: %d\n", ret);
645			return ret;
646		}
647	}
648
649	return 0;
650}
651
652enum {
653	DLN2_ACPI_MATCH_GPIO	= 0,
654	DLN2_ACPI_MATCH_I2C	= 1,
655	DLN2_ACPI_MATCH_SPI	= 2,
 
656};
657
658static struct dln2_platform_data dln2_pdata_gpio = {
659	.handle = DLN2_HANDLE_GPIO,
660};
661
662static struct mfd_cell_acpi_match dln2_acpi_match_gpio = {
663	.adr = DLN2_ACPI_MATCH_GPIO,
664};
665
666/* Only one I2C port seems to be supported on current hardware */
667static struct dln2_platform_data dln2_pdata_i2c = {
668	.handle = DLN2_HANDLE_I2C,
669	.port = 0,
670};
671
672static struct mfd_cell_acpi_match dln2_acpi_match_i2c = {
673	.adr = DLN2_ACPI_MATCH_I2C,
674};
675
676/* Only one SPI port supported */
677static struct dln2_platform_data dln2_pdata_spi = {
678	.handle = DLN2_HANDLE_SPI,
679	.port = 0,
680};
681
682static struct mfd_cell_acpi_match dln2_acpi_match_spi = {
683	.adr = DLN2_ACPI_MATCH_SPI,
684};
685
 
 
 
 
 
 
 
 
 
 
686static const struct mfd_cell dln2_devs[] = {
687	{
688		.name = "dln2-gpio",
689		.acpi_match = &dln2_acpi_match_gpio,
690		.platform_data = &dln2_pdata_gpio,
691		.pdata_size = sizeof(struct dln2_platform_data),
692	},
693	{
694		.name = "dln2-i2c",
695		.acpi_match = &dln2_acpi_match_i2c,
696		.platform_data = &dln2_pdata_i2c,
697		.pdata_size = sizeof(struct dln2_platform_data),
698	},
699	{
700		.name = "dln2-spi",
701		.acpi_match = &dln2_acpi_match_spi,
702		.platform_data = &dln2_pdata_spi,
703		.pdata_size = sizeof(struct dln2_platform_data),
704	},
 
 
 
 
 
 
705};
706
707static void dln2_stop(struct dln2_dev *dln2)
708{
709	int i, j;
710
711	/* don't allow starting new transfers */
712	spin_lock(&dln2->disconnect_lock);
713	dln2->disconnect = true;
714	spin_unlock(&dln2->disconnect_lock);
715
716	/* cancel in progress transfers */
717	for (i = 0; i < DLN2_HANDLES; i++) {
718		struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[i];
719		unsigned long flags;
720
721		spin_lock_irqsave(&rxs->lock, flags);
722
723		/* cancel all response waiters */
724		for (j = 0; j < DLN2_MAX_RX_SLOTS; j++) {
725			struct dln2_rx_context *rxc = &rxs->slots[j];
726
727			if (rxc->in_use)
728				complete(&rxc->done);
729		}
730
731		spin_unlock_irqrestore(&rxs->lock, flags);
732	}
733
734	/* wait for transfers to end */
735	wait_event(dln2->disconnect_wq, !dln2->active_transfers);
736
737	dln2_stop_rx_urbs(dln2);
738}
739
740static void dln2_disconnect(struct usb_interface *interface)
741{
742	struct dln2_dev *dln2 = usb_get_intfdata(interface);
743
744	dln2_stop(dln2);
745
746	mfd_remove_devices(&interface->dev);
747
748	dln2_free(dln2);
749}
750
751static int dln2_probe(struct usb_interface *interface,
752		      const struct usb_device_id *usb_id)
753{
754	struct usb_host_interface *hostif = interface->cur_altsetting;
755	struct usb_endpoint_descriptor *epin;
756	struct usb_endpoint_descriptor *epout;
757	struct device *dev = &interface->dev;
758	struct dln2_dev *dln2;
759	int ret;
760	int i, j;
761
762	if (hostif->desc.bInterfaceNumber != 0 ||
763	    hostif->desc.bNumEndpoints < 2)
764		return -ENODEV;
765
766	epout = &hostif->endpoint[DLN2_EP_OUT].desc;
767	if (!usb_endpoint_is_bulk_out(epout))
768		return -ENODEV;
769	epin = &hostif->endpoint[DLN2_EP_IN].desc;
770	if (!usb_endpoint_is_bulk_in(epin))
771		return -ENODEV;
772
773	dln2 = kzalloc(sizeof(*dln2), GFP_KERNEL);
774	if (!dln2)
775		return -ENOMEM;
776
777	dln2->ep_out = epout->bEndpointAddress;
778	dln2->ep_in = epin->bEndpointAddress;
779	dln2->usb_dev = usb_get_dev(interface_to_usbdev(interface));
780	dln2->interface = interface;
781	usb_set_intfdata(interface, dln2);
782	init_waitqueue_head(&dln2->disconnect_wq);
783
784	for (i = 0; i < DLN2_HANDLES; i++) {
785		init_waitqueue_head(&dln2->mod_rx_slots[i].wq);
786		spin_lock_init(&dln2->mod_rx_slots[i].lock);
787		for (j = 0; j < DLN2_MAX_RX_SLOTS; j++)
788			init_completion(&dln2->mod_rx_slots[i].slots[j].done);
789	}
790
791	spin_lock_init(&dln2->event_cb_lock);
792	spin_lock_init(&dln2->disconnect_lock);
793	INIT_LIST_HEAD(&dln2->event_cb_list);
794
795	ret = dln2_setup_rx_urbs(dln2, hostif);
796	if (ret)
797		goto out_free;
798
799	ret = dln2_start_rx_urbs(dln2, GFP_KERNEL);
800	if (ret)
801		goto out_stop_rx;
802
803	ret = dln2_hw_init(dln2);
804	if (ret < 0) {
805		dev_err(dev, "failed to initialize hardware\n");
806		goto out_stop_rx;
807	}
808
809	ret = mfd_add_hotplug_devices(dev, dln2_devs, ARRAY_SIZE(dln2_devs));
810	if (ret != 0) {
811		dev_err(dev, "failed to add mfd devices to core\n");
812		goto out_stop_rx;
813	}
814
815	return 0;
816
817out_stop_rx:
818	dln2_stop_rx_urbs(dln2);
819
820out_free:
821	dln2_free(dln2);
822
823	return ret;
824}
825
826static int dln2_suspend(struct usb_interface *iface, pm_message_t message)
827{
828	struct dln2_dev *dln2 = usb_get_intfdata(iface);
829
830	dln2_stop(dln2);
831
832	return 0;
833}
834
835static int dln2_resume(struct usb_interface *iface)
836{
837	struct dln2_dev *dln2 = usb_get_intfdata(iface);
838
839	dln2->disconnect = false;
840
841	return dln2_start_rx_urbs(dln2, GFP_NOIO);
842}
843
844static const struct usb_device_id dln2_table[] = {
845	{ USB_DEVICE(0xa257, 0x2013) },
846	{ }
847};
848
849MODULE_DEVICE_TABLE(usb, dln2_table);
850
851static struct usb_driver dln2_driver = {
852	.name = "dln2",
853	.probe = dln2_probe,
854	.disconnect = dln2_disconnect,
855	.id_table = dln2_table,
856	.suspend = dln2_suspend,
857	.resume = dln2_resume,
858};
859
860module_usb_driver(dln2_driver);
861
862MODULE_AUTHOR("Octavian Purdila <octavian.purdila@intel.com>");
863MODULE_DESCRIPTION("Core driver for the Diolan DLN2 interface adapter");
864MODULE_LICENSE("GPL v2");
v6.2
  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");