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
26#define VERSION "1.0"
27
28static struct usb_device_id nfcmrvl_table[] = {
29	{ USB_DEVICE_INTERFACE_CLASS(0x1286, 0x2046, 0xff) },
30	{ }	/* Terminating entry */
31};
32
33MODULE_DEVICE_TABLE(usb, nfcmrvl_table);
34
35#define NFCMRVL_USB_BULK_RUNNING	1
36#define NFCMRVL_USB_SUSPENDING		2
37
38struct nfcmrvl_usb_drv_data {
39	struct usb_device *udev;
40	struct usb_interface *intf;
41	unsigned long flags;
42	struct work_struct waker;
43	struct usb_anchor tx_anchor;
44	struct usb_anchor bulk_anchor;
45	struct usb_anchor deferred;
46	int tx_in_flight;
47	/* protects tx_in_flight */
48	spinlock_t txlock;
49	struct usb_endpoint_descriptor *bulk_tx_ep;
50	struct usb_endpoint_descriptor *bulk_rx_ep;
51	int suspend_count;
52	struct nfcmrvl_private *priv;
53};
54
55static int nfcmrvl_inc_tx(struct nfcmrvl_usb_drv_data *drv_data)
56{
57	unsigned long flags;
58	int rv;
59
60	spin_lock_irqsave(&drv_data->txlock, flags);
61	rv = test_bit(NFCMRVL_USB_SUSPENDING, &drv_data->flags);
62	if (!rv)
63		drv_data->tx_in_flight++;
64	spin_unlock_irqrestore(&drv_data->txlock, flags);
65
66	return rv;
67}
68
69static void nfcmrvl_bulk_complete(struct urb *urb)
70{
71	struct nfcmrvl_usb_drv_data *drv_data = urb->context;
72	int err;
73
74	dev_dbg(&drv_data->udev->dev, "urb %p status %d count %d",
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		if (nfcmrvl_nci_recv_frame(drv_data->priv, urb->transfer_buffer,
82					   urb->actual_length) < 0)
83			nfc_err(&drv_data->udev->dev, "corrupted Rx packet\n");
84	}
85
86	if (!test_bit(NFCMRVL_USB_BULK_RUNNING, &drv_data->flags))
87		return;
88
89	usb_anchor_urb(urb, &drv_data->bulk_anchor);
90	usb_mark_last_busy(drv_data->udev);
91
92	err = usb_submit_urb(urb, GFP_ATOMIC);
93	if (err) {
94		/* -EPERM: urb is being killed;
95		 * -ENODEV: device got disconnected
96		 */
97		if (err != -EPERM && err != -ENODEV)
98			nfc_err(&drv_data->udev->dev,
99				"urb %p failed to resubmit (%d)\n", urb, -err);
100		usb_unanchor_urb(urb);
101	}
102}
103
104static int
105nfcmrvl_submit_bulk_urb(struct nfcmrvl_usb_drv_data *drv_data, gfp_t mem_flags)
106{
107	struct urb *urb;
108	unsigned char *buf;
109	unsigned int pipe;
110	int err, size = NFCMRVL_NCI_MAX_EVENT_SIZE;
111
112	if (!drv_data->bulk_rx_ep)
113		return -ENODEV;
114
115	urb = usb_alloc_urb(0, mem_flags);
116	if (!urb)
117		return -ENOMEM;
118
119	buf = kmalloc(size, mem_flags);
120	if (!buf) {
121		usb_free_urb(urb);
122		return -ENOMEM;
123	}
124
125	pipe = usb_rcvbulkpipe(drv_data->udev,
126			       drv_data->bulk_rx_ep->bEndpointAddress);
127
128	usb_fill_bulk_urb(urb, drv_data->udev, pipe, buf, size,
129			  nfcmrvl_bulk_complete, drv_data);
130
131	urb->transfer_flags |= URB_FREE_BUFFER;
132
133	usb_mark_last_busy(drv_data->udev);
134	usb_anchor_urb(urb, &drv_data->bulk_anchor);
135
136	err = usb_submit_urb(urb, mem_flags);
137	if (err) {
138		if (err != -EPERM && err != -ENODEV)
139			nfc_err(&drv_data->udev->dev,
140				"urb %p submission failed (%d)\n", urb, -err);
141		usb_unanchor_urb(urb);
142	}
143
144	usb_free_urb(urb);
145
146	return err;
147}
148
149static void nfcmrvl_tx_complete(struct urb *urb)
150{
151	struct sk_buff *skb = urb->context;
152	struct nci_dev *ndev = (struct nci_dev *)skb->dev;
153	struct nfcmrvl_private *priv = nci_get_drvdata(ndev);
154	struct nfcmrvl_usb_drv_data *drv_data = priv->drv_data;
155
156	nfc_info(priv->dev, "urb %p status %d count %d\n",
157		 urb, urb->status, urb->actual_length);
158
159	spin_lock(&drv_data->txlock);
160	drv_data->tx_in_flight--;
161	spin_unlock(&drv_data->txlock);
162
163	kfree(urb->setup_packet);
164	kfree_skb(skb);
165}
166
167static int nfcmrvl_usb_nci_open(struct nfcmrvl_private *priv)
168{
169	struct nfcmrvl_usb_drv_data *drv_data = priv->drv_data;
170	int err;
171
172	err = usb_autopm_get_interface(drv_data->intf);
173	if (err)
174		return err;
175
176	drv_data->intf->needs_remote_wakeup = 1;
177
178	err = nfcmrvl_submit_bulk_urb(drv_data, GFP_KERNEL);
179	if (err)
180		goto failed;
181
182	set_bit(NFCMRVL_USB_BULK_RUNNING, &drv_data->flags);
183	nfcmrvl_submit_bulk_urb(drv_data, GFP_KERNEL);
184
185	usb_autopm_put_interface(drv_data->intf);
186	return 0;
187
188failed:
189	usb_autopm_put_interface(drv_data->intf);
190	return err;
191}
192
193static void nfcmrvl_usb_stop_traffic(struct nfcmrvl_usb_drv_data *drv_data)
194{
195	usb_kill_anchored_urbs(&drv_data->bulk_anchor);
196}
197
198static int nfcmrvl_usb_nci_close(struct nfcmrvl_private *priv)
199{
200	struct nfcmrvl_usb_drv_data *drv_data = priv->drv_data;
201	int err;
202
203	cancel_work_sync(&drv_data->waker);
204
205	clear_bit(NFCMRVL_USB_BULK_RUNNING, &drv_data->flags);
206
207	nfcmrvl_usb_stop_traffic(drv_data);
208	usb_kill_anchored_urbs(&drv_data->tx_anchor);
209	err = usb_autopm_get_interface(drv_data->intf);
210	if (err)
211		goto failed;
212
213	drv_data->intf->needs_remote_wakeup = 0;
214	usb_autopm_put_interface(drv_data->intf);
215
216failed:
217	usb_scuttle_anchored_urbs(&drv_data->deferred);
218	return 0;
219}
220
221static int nfcmrvl_usb_nci_send(struct nfcmrvl_private *priv,
222				struct sk_buff *skb)
223{
224	struct nfcmrvl_usb_drv_data *drv_data = priv->drv_data;
225	struct urb *urb;
226	unsigned int pipe;
227	int err;
228
229	if (!drv_data->bulk_tx_ep)
230		return -ENODEV;
231
232	urb = usb_alloc_urb(0, GFP_ATOMIC);
233	if (!urb)
234		return -ENOMEM;
235
236	pipe = usb_sndbulkpipe(drv_data->udev,
237				drv_data->bulk_tx_ep->bEndpointAddress);
238
239	usb_fill_bulk_urb(urb, drv_data->udev, pipe, skb->data, skb->len,
240			  nfcmrvl_tx_complete, skb);
241
242	err = nfcmrvl_inc_tx(drv_data);
243	if (err) {
244		usb_anchor_urb(urb, &drv_data->deferred);
245		schedule_work(&drv_data->waker);
246		err = 0;
247		goto done;
248	}
249
250	usb_anchor_urb(urb, &drv_data->tx_anchor);
251
252	err = usb_submit_urb(urb, GFP_ATOMIC);
253	if (err) {
254		if (err != -EPERM && err != -ENODEV)
255			nfc_err(&drv_data->udev->dev,
256				"urb %p submission failed (%d)\n", urb, -err);
257		kfree(urb->setup_packet);
258		usb_unanchor_urb(urb);
259	} else {
260		usb_mark_last_busy(drv_data->udev);
261	}
262
263done:
264	usb_free_urb(urb);
265	return err;
266}
267
268static struct nfcmrvl_if_ops usb_ops = {
269	.nci_open = nfcmrvl_usb_nci_open,
270	.nci_close = nfcmrvl_usb_nci_close,
271	.nci_send = nfcmrvl_usb_nci_send,
272};
273
274static void nfcmrvl_waker(struct work_struct *work)
275{
276	struct nfcmrvl_usb_drv_data *drv_data =
277			container_of(work, struct nfcmrvl_usb_drv_data, waker);
278	int err;
279
280	err = usb_autopm_get_interface(drv_data->intf);
281	if (err)
282		return;
283
284	usb_autopm_put_interface(drv_data->intf);
285}
286
287static int nfcmrvl_probe(struct usb_interface *intf,
288			 const struct usb_device_id *id)
289{
290	struct usb_endpoint_descriptor *ep_desc;
291	struct nfcmrvl_usb_drv_data *drv_data;
292	struct nfcmrvl_private *priv;
293	int i;
294	struct usb_device *udev = interface_to_usbdev(intf);
295
296	nfc_info(&udev->dev, "intf %p id %p\n", intf, id);
297
298	drv_data = devm_kzalloc(&intf->dev, sizeof(*drv_data), GFP_KERNEL);
299	if (!drv_data)
300		return -ENOMEM;
301
302	for (i = 0; i < intf->cur_altsetting->desc.bNumEndpoints; i++) {
303		ep_desc = &intf->cur_altsetting->endpoint[i].desc;
304
305		if (!drv_data->bulk_tx_ep &&
306		    usb_endpoint_is_bulk_out(ep_desc)) {
307			drv_data->bulk_tx_ep = ep_desc;
308			continue;
309		}
310
311		if (!drv_data->bulk_rx_ep &&
312		    usb_endpoint_is_bulk_in(ep_desc)) {
313			drv_data->bulk_rx_ep = ep_desc;
314			continue;
315		}
316	}
317
318	if (!drv_data->bulk_tx_ep || !drv_data->bulk_rx_ep)
319		return -ENODEV;
320
321	drv_data->udev = udev;
322	drv_data->intf = intf;
323
324	INIT_WORK(&drv_data->waker, nfcmrvl_waker);
325	spin_lock_init(&drv_data->txlock);
326
327	init_usb_anchor(&drv_data->tx_anchor);
328	init_usb_anchor(&drv_data->bulk_anchor);
329	init_usb_anchor(&drv_data->deferred);
330
331	priv = nfcmrvl_nci_register_dev(drv_data, &usb_ops,
332					&drv_data->udev->dev);
333	if (IS_ERR(priv))
334		return PTR_ERR(priv);
335
336	drv_data->priv = priv;
337	priv->dev = &drv_data->udev->dev;
338
339	usb_set_intfdata(intf, drv_data);
340
341	return 0;
342}
343
344static void nfcmrvl_disconnect(struct usb_interface *intf)
345{
346	struct nfcmrvl_usb_drv_data *drv_data = usb_get_intfdata(intf);
347
348	if (!drv_data)
349		return;
350
351	nfc_info(&drv_data->udev->dev, "intf %p\n", intf);
352
353	nfcmrvl_nci_unregister_dev(drv_data->priv);
354
355	usb_set_intfdata(drv_data->intf, NULL);
356}
357
358#ifdef CONFIG_PM
359static int nfcmrvl_suspend(struct usb_interface *intf, pm_message_t message)
360{
361	struct nfcmrvl_usb_drv_data *drv_data = usb_get_intfdata(intf);
362
363	nfc_info(&drv_data->udev->dev, "intf %p\n", intf);
364
365	if (drv_data->suspend_count++)
366		return 0;
367
368	spin_lock_irq(&drv_data->txlock);
369	if (!(PMSG_IS_AUTO(message) && drv_data->tx_in_flight)) {
370		set_bit(NFCMRVL_USB_SUSPENDING, &drv_data->flags);
371		spin_unlock_irq(&drv_data->txlock);
372	} else {
373		spin_unlock_irq(&drv_data->txlock);
374		drv_data->suspend_count--;
375		return -EBUSY;
376	}
377
378	nfcmrvl_usb_stop_traffic(drv_data);
379	usb_kill_anchored_urbs(&drv_data->tx_anchor);
380
381	return 0;
382}
383
384static void nfcmrvl_play_deferred(struct nfcmrvl_usb_drv_data *drv_data)
385{
386	struct urb *urb;
387	int err;
388
389	while ((urb = usb_get_from_anchor(&drv_data->deferred))) {
390		err = usb_submit_urb(urb, GFP_ATOMIC);
391		if (err)
392			break;
393
394		drv_data->tx_in_flight++;
395	}
396	usb_scuttle_anchored_urbs(&drv_data->deferred);
397}
398
399static int nfcmrvl_resume(struct usb_interface *intf)
400{
401	struct nfcmrvl_usb_drv_data *drv_data = usb_get_intfdata(intf);
402	int err = 0;
403
404	nfc_info(&drv_data->udev->dev, "intf %p\n", intf);
405
406	if (--drv_data->suspend_count)
407		return 0;
408
409	if (!test_bit(NFCMRVL_NCI_RUNNING, &drv_data->flags))
410		goto done;
411
412	if (test_bit(NFCMRVL_USB_BULK_RUNNING, &drv_data->flags)) {
413		err = nfcmrvl_submit_bulk_urb(drv_data, GFP_NOIO);
414		if (err) {
415			clear_bit(NFCMRVL_USB_BULK_RUNNING, &drv_data->flags);
416			goto failed;
417		}
418
419		nfcmrvl_submit_bulk_urb(drv_data, GFP_NOIO);
420	}
421
422	spin_lock_irq(&drv_data->txlock);
423	nfcmrvl_play_deferred(drv_data);
424	clear_bit(NFCMRVL_USB_SUSPENDING, &drv_data->flags);
425	spin_unlock_irq(&drv_data->txlock);
426
427	return 0;
428
429failed:
430	usb_scuttle_anchored_urbs(&drv_data->deferred);
431done:
432	spin_lock_irq(&drv_data->txlock);
433	clear_bit(NFCMRVL_USB_SUSPENDING, &drv_data->flags);
434	spin_unlock_irq(&drv_data->txlock);
435
436	return err;
437}
438#endif
439
440static struct usb_driver nfcmrvl_usb_driver = {
441	.name		= "nfcmrvl",
442	.probe		= nfcmrvl_probe,
443	.disconnect	= nfcmrvl_disconnect,
444#ifdef CONFIG_PM
445	.suspend	= nfcmrvl_suspend,
446	.resume		= nfcmrvl_resume,
447	.reset_resume	= nfcmrvl_resume,
448#endif
449	.id_table	= nfcmrvl_table,
450	.supports_autosuspend = 1,
451	.disable_hub_initiated_lpm = 1,
452	.soft_unbind = 1,
453};
454module_usb_driver(nfcmrvl_usb_driver);
455
456MODULE_AUTHOR("Marvell International Ltd.");
457MODULE_DESCRIPTION("Marvell NFC-over-USB driver ver " VERSION);
458MODULE_VERSION(VERSION);
459MODULE_LICENSE("GPL v2");
460