1/**
2 * Marvell NFC-over-USB driver: USB interface related functions
3 *
4 * Copyright (C) 2014, Marvell International Ltd.
5 *
6 * This software file (the "File") is distributed by Marvell International
7 * Ltd. under the terms of the GNU General Public License Version 2, June 1991
8 * (the "License").  You may use, redistribute and/or modify this File in
9 * accordance with the terms and conditions of the License, a copy of which
10 * is available on the worldwide web at
11 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
12 *
13 * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
14 * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
15 * ARE EXPRESSLY DISCLAIMED.  The License provides additional details about
16 * this warranty disclaimer.
17 **/
18
19#include <linux/module.h>
20#include <linux/usb.h>
21#include <linux/nfc.h>
22#include <net/nfc/nci.h>
23#include <net/nfc/nci_core.h>
24#include "nfcmrvl.h"
25
26static struct usb_device_id nfcmrvl_table[] = {
27	{ USB_DEVICE_AND_INTERFACE_INFO(0x1286, 0x2046,
28					USB_CLASS_VENDOR_SPEC, 4, 1) },
29	{ }	/* Terminating entry */
30};
31
32MODULE_DEVICE_TABLE(usb, nfcmrvl_table);
33
34#define NFCMRVL_USB_BULK_RUNNING	1
35#define NFCMRVL_USB_SUSPENDING		2
36
37struct nfcmrvl_usb_drv_data {
38	struct usb_device *udev;
39	struct usb_interface *intf;
40	unsigned long flags;
41	struct work_struct waker;
42	struct usb_anchor tx_anchor;
43	struct usb_anchor bulk_anchor;
44	struct usb_anchor deferred;
45	int tx_in_flight;
46	/* protects tx_in_flight */
47	spinlock_t txlock;
48	struct usb_endpoint_descriptor *bulk_tx_ep;
49	struct usb_endpoint_descriptor *bulk_rx_ep;
50	int suspend_count;
51	struct nfcmrvl_private *priv;
52};
53
54static int nfcmrvl_inc_tx(struct nfcmrvl_usb_drv_data *drv_data)
55{
56	unsigned long flags;
57	int rv;
58
59	spin_lock_irqsave(&drv_data->txlock, flags);
60	rv = test_bit(NFCMRVL_USB_SUSPENDING, &drv_data->flags);
61	if (!rv)
62		drv_data->tx_in_flight++;
63	spin_unlock_irqrestore(&drv_data->txlock, flags);
64
65	return rv;
66}
67
68static void nfcmrvl_bulk_complete(struct urb *urb)
69{
70	struct nfcmrvl_usb_drv_data *drv_data = urb->context;
71	struct sk_buff *skb;
72	int err;
73
74	dev_dbg(&drv_data->udev->dev, "urb %p status %d count %d\n",
75		urb, urb->status, urb->actual_length);
76
77	if (!test_bit(NFCMRVL_NCI_RUNNING, &drv_data->flags))
78		return;
79
80	if (!urb->status) {
81		skb = nci_skb_alloc(drv_data->priv->ndev, urb->actual_length,
82				    GFP_ATOMIC);
83		if (!skb) {
84			nfc_err(&drv_data->udev->dev, "failed to alloc mem\n");
85		} else {
86			memcpy(skb_put(skb, urb->actual_length),
87			       urb->transfer_buffer, urb->actual_length);
88			if (nfcmrvl_nci_recv_frame(drv_data->priv, skb) < 0)
89				nfc_err(&drv_data->udev->dev,
90					"corrupted Rx packet\n");
91		}
92	}
93
94	if (!test_bit(NFCMRVL_USB_BULK_RUNNING, &drv_data->flags))
95		return;
96
97	usb_anchor_urb(urb, &drv_data->bulk_anchor);
98	usb_mark_last_busy(drv_data->udev);
99
100	err = usb_submit_urb(urb, GFP_ATOMIC);
101	if (err) {
102		/* -EPERM: urb is being killed;
103		 * -ENODEV: device got disconnected
104		 */
105		if (err != -EPERM && err != -ENODEV)
106			nfc_err(&drv_data->udev->dev,
107				"urb %p failed to resubmit (%d)\n", urb, -err);
108		usb_unanchor_urb(urb);
109	}
110}
111
112static int
113nfcmrvl_submit_bulk_urb(struct nfcmrvl_usb_drv_data *drv_data, gfp_t mem_flags)
114{
115	struct urb *urb;
116	unsigned char *buf;
117	unsigned int pipe;
118	int err, size = NFCMRVL_NCI_MAX_EVENT_SIZE;
119
120	if (!drv_data->bulk_rx_ep)
121		return -ENODEV;
122
123	urb = usb_alloc_urb(0, mem_flags);
124	if (!urb)
125		return -ENOMEM;
126
127	buf = kmalloc(size, mem_flags);
128	if (!buf) {
129		usb_free_urb(urb);
130		return -ENOMEM;
131	}
132
133	pipe = usb_rcvbulkpipe(drv_data->udev,
134			       drv_data->bulk_rx_ep->bEndpointAddress);
135
136	usb_fill_bulk_urb(urb, drv_data->udev, pipe, buf, size,
137			  nfcmrvl_bulk_complete, drv_data);
138
139	urb->transfer_flags |= URB_FREE_BUFFER;
140
141	usb_mark_last_busy(drv_data->udev);
142	usb_anchor_urb(urb, &drv_data->bulk_anchor);
143
144	err = usb_submit_urb(urb, mem_flags);
145	if (err) {
146		if (err != -EPERM && err != -ENODEV)
147			nfc_err(&drv_data->udev->dev,
148				"urb %p submission failed (%d)\n", urb, -err);
149		usb_unanchor_urb(urb);
150	}
151
152	usb_free_urb(urb);
153
154	return err;
155}
156
157static void nfcmrvl_tx_complete(struct urb *urb)
158{
159	struct sk_buff *skb = urb->context;
160	struct nci_dev *ndev = (struct nci_dev *)skb->dev;
161	struct nfcmrvl_private *priv = nci_get_drvdata(ndev);
162	struct nfcmrvl_usb_drv_data *drv_data = priv->drv_data;
163
164	nfc_info(priv->dev, "urb %p status %d count %d\n",
165		 urb, urb->status, urb->actual_length);
166
167	spin_lock(&drv_data->txlock);
168	drv_data->tx_in_flight--;
169	spin_unlock(&drv_data->txlock);
170
171	kfree(urb->setup_packet);
172	kfree_skb(skb);
173}
174
175static int nfcmrvl_usb_nci_open(struct nfcmrvl_private *priv)
176{
177	struct nfcmrvl_usb_drv_data *drv_data = priv->drv_data;
178	int err;
179
180	err = usb_autopm_get_interface(drv_data->intf);
181	if (err)
182		return err;
183
184	drv_data->intf->needs_remote_wakeup = 1;
185
186	err = nfcmrvl_submit_bulk_urb(drv_data, GFP_KERNEL);
187	if (err)
188		goto failed;
189
190	set_bit(NFCMRVL_USB_BULK_RUNNING, &drv_data->flags);
191	nfcmrvl_submit_bulk_urb(drv_data, GFP_KERNEL);
192
193	usb_autopm_put_interface(drv_data->intf);
194	return 0;
195
196failed:
197	usb_autopm_put_interface(drv_data->intf);
198	return err;
199}
200
201static void nfcmrvl_usb_stop_traffic(struct nfcmrvl_usb_drv_data *drv_data)
202{
203	usb_kill_anchored_urbs(&drv_data->bulk_anchor);
204}
205
206static int nfcmrvl_usb_nci_close(struct nfcmrvl_private *priv)
207{
208	struct nfcmrvl_usb_drv_data *drv_data = priv->drv_data;
209	int err;
210
211	cancel_work_sync(&drv_data->waker);
212
213	clear_bit(NFCMRVL_USB_BULK_RUNNING, &drv_data->flags);
214
215	nfcmrvl_usb_stop_traffic(drv_data);
216	usb_kill_anchored_urbs(&drv_data->tx_anchor);
217	err = usb_autopm_get_interface(drv_data->intf);
218	if (err)
219		goto failed;
220
221	drv_data->intf->needs_remote_wakeup = 0;
222	usb_autopm_put_interface(drv_data->intf);
223
224failed:
225	usb_scuttle_anchored_urbs(&drv_data->deferred);
226	return 0;
227}
228
229static int nfcmrvl_usb_nci_send(struct nfcmrvl_private *priv,
230				struct sk_buff *skb)
231{
232	struct nfcmrvl_usb_drv_data *drv_data = priv->drv_data;
233	struct urb *urb;
234	unsigned int pipe;
235	int err;
236
237	if (!drv_data->bulk_tx_ep)
238		return -ENODEV;
239
240	urb = usb_alloc_urb(0, GFP_ATOMIC);
241	if (!urb)
242		return -ENOMEM;
243
244	pipe = usb_sndbulkpipe(drv_data->udev,
245				drv_data->bulk_tx_ep->bEndpointAddress);
246
247	usb_fill_bulk_urb(urb, drv_data->udev, pipe, skb->data, skb->len,
248			  nfcmrvl_tx_complete, skb);
249
250	err = nfcmrvl_inc_tx(drv_data);
251	if (err) {
252		usb_anchor_urb(urb, &drv_data->deferred);
253		schedule_work(&drv_data->waker);
254		err = 0;
255		goto done;
256	}
257
258	usb_anchor_urb(urb, &drv_data->tx_anchor);
259
260	err = usb_submit_urb(urb, GFP_ATOMIC);
261	if (err) {
262		if (err != -EPERM && err != -ENODEV)
263			nfc_err(&drv_data->udev->dev,
264				"urb %p submission failed (%d)\n", urb, -err);
265		kfree(urb->setup_packet);
266		usb_unanchor_urb(urb);
267	} else {
268		usb_mark_last_busy(drv_data->udev);
269	}
270
271done:
272	usb_free_urb(urb);
273	return err;
274}
275
276static struct nfcmrvl_if_ops usb_ops = {
277	.nci_open = nfcmrvl_usb_nci_open,
278	.nci_close = nfcmrvl_usb_nci_close,
279	.nci_send = nfcmrvl_usb_nci_send,
280};
281
282static void nfcmrvl_waker(struct work_struct *work)
283{
284	struct nfcmrvl_usb_drv_data *drv_data =
285			container_of(work, struct nfcmrvl_usb_drv_data, waker);
286	int err;
287
288	err = usb_autopm_get_interface(drv_data->intf);
289	if (err)
290		return;
291
292	usb_autopm_put_interface(drv_data->intf);
293}
294
295static int nfcmrvl_probe(struct usb_interface *intf,
296			 const struct usb_device_id *id)
297{
298	struct usb_endpoint_descriptor *ep_desc;
299	struct nfcmrvl_usb_drv_data *drv_data;
300	struct nfcmrvl_private *priv;
301	int i;
302	struct usb_device *udev = interface_to_usbdev(intf);
303	struct nfcmrvl_platform_data config;
304
305	/* No configuration for USB */
306	memset(&config, 0, sizeof(config));
307
308	nfc_info(&udev->dev, "intf %p id %p\n", intf, id);
309
310	drv_data = devm_kzalloc(&intf->dev, sizeof(*drv_data), GFP_KERNEL);
311	if (!drv_data)
312		return -ENOMEM;
313
314	for (i = 0; i < intf->cur_altsetting->desc.bNumEndpoints; i++) {
315		ep_desc = &intf->cur_altsetting->endpoint[i].desc;
316
317		if (!drv_data->bulk_tx_ep &&
318		    usb_endpoint_is_bulk_out(ep_desc)) {
319			drv_data->bulk_tx_ep = ep_desc;
320			continue;
321		}
322
323		if (!drv_data->bulk_rx_ep &&
324		    usb_endpoint_is_bulk_in(ep_desc)) {
325			drv_data->bulk_rx_ep = ep_desc;
326			continue;
327		}
328	}
329
330	if (!drv_data->bulk_tx_ep || !drv_data->bulk_rx_ep)
331		return -ENODEV;
332
333	drv_data->udev = udev;
334	drv_data->intf = intf;
335
336	INIT_WORK(&drv_data->waker, nfcmrvl_waker);
337	spin_lock_init(&drv_data->txlock);
338
339	init_usb_anchor(&drv_data->tx_anchor);
340	init_usb_anchor(&drv_data->bulk_anchor);
341	init_usb_anchor(&drv_data->deferred);
342
343	priv = nfcmrvl_nci_register_dev(NFCMRVL_PHY_USB, drv_data, &usb_ops,
344					&drv_data->udev->dev, &config);
345	if (IS_ERR(priv))
346		return PTR_ERR(priv);
347
348	drv_data->priv = priv;
349	drv_data->priv->support_fw_dnld = false;
350
351	priv->dev = &drv_data->udev->dev;
352
353	usb_set_intfdata(intf, drv_data);
354
355	return 0;
356}
357
358static void nfcmrvl_disconnect(struct usb_interface *intf)
359{
360	struct nfcmrvl_usb_drv_data *drv_data = usb_get_intfdata(intf);
361
362	if (!drv_data)
363		return;
364
365	nfc_info(&drv_data->udev->dev, "intf %p\n", intf);
366
367	nfcmrvl_nci_unregister_dev(drv_data->priv);
368
369	usb_set_intfdata(drv_data->intf, NULL);
370}
371
372#ifdef CONFIG_PM
373static int nfcmrvl_suspend(struct usb_interface *intf, pm_message_t message)
374{
375	struct nfcmrvl_usb_drv_data *drv_data = usb_get_intfdata(intf);
376
377	nfc_info(&drv_data->udev->dev, "intf %p\n", intf);
378
379	if (drv_data->suspend_count++)
380		return 0;
381
382	spin_lock_irq(&drv_data->txlock);
383	if (!(PMSG_IS_AUTO(message) && drv_data->tx_in_flight)) {
384		set_bit(NFCMRVL_USB_SUSPENDING, &drv_data->flags);
385		spin_unlock_irq(&drv_data->txlock);
386	} else {
387		spin_unlock_irq(&drv_data->txlock);
388		drv_data->suspend_count--;
389		return -EBUSY;
390	}
391
392	nfcmrvl_usb_stop_traffic(drv_data);
393	usb_kill_anchored_urbs(&drv_data->tx_anchor);
394
395	return 0;
396}
397
398static void nfcmrvl_play_deferred(struct nfcmrvl_usb_drv_data *drv_data)
399{
400	struct urb *urb;
401	int err;
402
403	while ((urb = usb_get_from_anchor(&drv_data->deferred))) {
404		err = usb_submit_urb(urb, GFP_ATOMIC);
405		if (err)
406			break;
407
408		drv_data->tx_in_flight++;
409	}
410	usb_scuttle_anchored_urbs(&drv_data->deferred);
411}
412
413static int nfcmrvl_resume(struct usb_interface *intf)
414{
415	struct nfcmrvl_usb_drv_data *drv_data = usb_get_intfdata(intf);
416	int err = 0;
417
418	nfc_info(&drv_data->udev->dev, "intf %p\n", intf);
419
420	if (--drv_data->suspend_count)
421		return 0;
422
423	if (!test_bit(NFCMRVL_NCI_RUNNING, &drv_data->flags))
424		goto done;
425
426	if (test_bit(NFCMRVL_USB_BULK_RUNNING, &drv_data->flags)) {
427		err = nfcmrvl_submit_bulk_urb(drv_data, GFP_NOIO);
428		if (err) {
429			clear_bit(NFCMRVL_USB_BULK_RUNNING, &drv_data->flags);
430			goto failed;
431		}
432
433		nfcmrvl_submit_bulk_urb(drv_data, GFP_NOIO);
434	}
435
436	spin_lock_irq(&drv_data->txlock);
437	nfcmrvl_play_deferred(drv_data);
438	clear_bit(NFCMRVL_USB_SUSPENDING, &drv_data->flags);
439	spin_unlock_irq(&drv_data->txlock);
440
441	return 0;
442
443failed:
444	usb_scuttle_anchored_urbs(&drv_data->deferred);
445done:
446	spin_lock_irq(&drv_data->txlock);
447	clear_bit(NFCMRVL_USB_SUSPENDING, &drv_data->flags);
448	spin_unlock_irq(&drv_data->txlock);
449
450	return err;
451}
452#endif
453
454static struct usb_driver nfcmrvl_usb_driver = {
455	.name		= "nfcmrvl",
456	.probe		= nfcmrvl_probe,
457	.disconnect	= nfcmrvl_disconnect,
458#ifdef CONFIG_PM
459	.suspend	= nfcmrvl_suspend,
460	.resume		= nfcmrvl_resume,
461	.reset_resume	= nfcmrvl_resume,
462#endif
463	.id_table	= nfcmrvl_table,
464	.supports_autosuspend = 1,
465	.disable_hub_initiated_lpm = 1,
466	.soft_unbind = 1,
467};
468module_usb_driver(nfcmrvl_usb_driver);
469
470MODULE_AUTHOR("Marvell International Ltd.");
471MODULE_DESCRIPTION("Marvell NFC-over-USB driver");
472MODULE_LICENSE("GPL v2");
473