xref: /linux/drivers/hid/hid-logitech-dj.c (revision cc04a46f11ea046ed53e2c832ae29e4790f7e35f)
1 /*
2  *  HID driver for Logitech Unifying receivers
3  *
4  *  Copyright (c) 2011 Logitech
5  */
6 
7 /*
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11 
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21  *
22  */
23 
24 
25 #include <linux/device.h>
26 #include <linux/hid.h>
27 #include <linux/module.h>
28 #include <linux/usb.h>
29 #include <linux/kfifo.h>
30 #include <asm/unaligned.h>
31 #include "hid-ids.h"
32 
33 #define DJ_MAX_PAIRED_DEVICES			6
34 #define DJ_MAX_NUMBER_NOTIFICATIONS		8
35 #define DJ_RECEIVER_INDEX			0
36 #define DJ_DEVICE_INDEX_MIN			1
37 #define DJ_DEVICE_INDEX_MAX			6
38 
39 #define DJREPORT_SHORT_LENGTH			15
40 #define DJREPORT_LONG_LENGTH			32
41 
42 #define REPORT_ID_DJ_SHORT			0x20
43 #define REPORT_ID_DJ_LONG			0x21
44 
45 #define REPORT_ID_HIDPP_SHORT			0x10
46 #define REPORT_ID_HIDPP_LONG			0x11
47 
48 #define HIDPP_REPORT_SHORT_LENGTH		7
49 #define HIDPP_REPORT_LONG_LENGTH		20
50 
51 #define HIDPP_RECEIVER_INDEX			0xff
52 
53 #define REPORT_TYPE_RFREPORT_FIRST		0x01
54 #define REPORT_TYPE_RFREPORT_LAST		0x1F
55 
56 /* Command Switch to DJ mode */
57 #define REPORT_TYPE_CMD_SWITCH			0x80
58 #define CMD_SWITCH_PARAM_DEVBITFIELD		0x00
59 #define CMD_SWITCH_PARAM_TIMEOUT_SECONDS	0x01
60 #define TIMEOUT_NO_KEEPALIVE			0x00
61 
62 /* Command to Get the list of Paired devices */
63 #define REPORT_TYPE_CMD_GET_PAIRED_DEVICES	0x81
64 
65 /* Device Paired Notification */
66 #define REPORT_TYPE_NOTIF_DEVICE_PAIRED		0x41
67 #define SPFUNCTION_MORE_NOTIF_EXPECTED		0x01
68 #define SPFUNCTION_DEVICE_LIST_EMPTY		0x02
69 #define DEVICE_PAIRED_PARAM_SPFUNCTION		0x00
70 #define DEVICE_PAIRED_PARAM_EQUAD_ID_LSB	0x01
71 #define DEVICE_PAIRED_PARAM_EQUAD_ID_MSB	0x02
72 #define DEVICE_PAIRED_RF_REPORT_TYPE		0x03
73 
74 /* Device Un-Paired Notification */
75 #define REPORT_TYPE_NOTIF_DEVICE_UNPAIRED	0x40
76 
77 
78 /* Connection Status Notification */
79 #define REPORT_TYPE_NOTIF_CONNECTION_STATUS	0x42
80 #define CONNECTION_STATUS_PARAM_STATUS		0x00
81 #define STATUS_LINKLOSS				0x01
82 
83 /* Error Notification */
84 #define REPORT_TYPE_NOTIF_ERROR			0x7F
85 #define NOTIF_ERROR_PARAM_ETYPE			0x00
86 #define ETYPE_KEEPALIVE_TIMEOUT			0x01
87 
88 /* supported DJ HID && RF report types */
89 #define REPORT_TYPE_KEYBOARD			0x01
90 #define REPORT_TYPE_MOUSE			0x02
91 #define REPORT_TYPE_CONSUMER_CONTROL		0x03
92 #define REPORT_TYPE_SYSTEM_CONTROL		0x04
93 #define REPORT_TYPE_MEDIA_CENTER		0x08
94 #define REPORT_TYPE_LEDS			0x0E
95 
96 /* RF Report types bitfield */
97 #define STD_KEYBOARD				0x00000002
98 #define STD_MOUSE				0x00000004
99 #define MULTIMEDIA				0x00000008
100 #define POWER_KEYS				0x00000010
101 #define MEDIA_CENTER				0x00000100
102 #define KBD_LEDS				0x00004000
103 
104 struct dj_report {
105 	u8 report_id;
106 	u8 device_index;
107 	u8 report_type;
108 	u8 report_params[DJREPORT_SHORT_LENGTH - 3];
109 };
110 
111 struct dj_receiver_dev {
112 	struct hid_device *hdev;
113 	struct dj_device *paired_dj_devices[DJ_MAX_PAIRED_DEVICES +
114 					    DJ_DEVICE_INDEX_MIN];
115 	struct work_struct work;
116 	struct kfifo notif_fifo;
117 	spinlock_t lock;
118 	bool querying_devices;
119 };
120 
121 struct dj_device {
122 	struct hid_device *hdev;
123 	struct dj_receiver_dev *dj_receiver_dev;
124 	u32 reports_supported;
125 	u8 device_index;
126 };
127 
128 /* Keyboard descriptor (1) */
129 static const char kbd_descriptor[] = {
130 	0x05, 0x01,		/* USAGE_PAGE (generic Desktop)     */
131 	0x09, 0x06,		/* USAGE (Keyboard)         */
132 	0xA1, 0x01,		/* COLLECTION (Application)     */
133 	0x85, 0x01,		/* REPORT_ID (1)            */
134 	0x95, 0x08,		/*   REPORT_COUNT (8)           */
135 	0x75, 0x01,		/*   REPORT_SIZE (1)            */
136 	0x15, 0x00,		/*   LOGICAL_MINIMUM (0)        */
137 	0x25, 0x01,		/*   LOGICAL_MAXIMUM (1)        */
138 	0x05, 0x07,		/*   USAGE_PAGE (Keyboard)      */
139 	0x19, 0xE0,		/*   USAGE_MINIMUM (Left Control)   */
140 	0x29, 0xE7,		/*   USAGE_MAXIMUM (Right GUI)      */
141 	0x81, 0x02,		/*   INPUT (Data,Var,Abs)       */
142 	0x95, 0x06,		/*   REPORT_COUNT (6)           */
143 	0x75, 0x08,		/*   REPORT_SIZE (8)            */
144 	0x15, 0x00,		/*   LOGICAL_MINIMUM (0)        */
145 	0x26, 0xFF, 0x00,	/*   LOGICAL_MAXIMUM (255)      */
146 	0x05, 0x07,		/*   USAGE_PAGE (Keyboard)      */
147 	0x19, 0x00,		/*   USAGE_MINIMUM (no event)       */
148 	0x2A, 0xFF, 0x00,	/*   USAGE_MAXIMUM (reserved)       */
149 	0x81, 0x00,		/*   INPUT (Data,Ary,Abs)       */
150 	0x85, 0x0e,		/* REPORT_ID (14)               */
151 	0x05, 0x08,		/*   USAGE PAGE (LED page)      */
152 	0x95, 0x05,		/*   REPORT COUNT (5)           */
153 	0x75, 0x01,		/*   REPORT SIZE (1)            */
154 	0x15, 0x00,		/*   LOGICAL_MINIMUM (0)        */
155 	0x25, 0x01,		/*   LOGICAL_MAXIMUM (1)        */
156 	0x19, 0x01,		/*   USAGE MINIMUM (1)          */
157 	0x29, 0x05,		/*   USAGE MAXIMUM (5)          */
158 	0x91, 0x02,		/*   OUTPUT (Data, Variable, Absolute)  */
159 	0x95, 0x01,		/*   REPORT COUNT (1)           */
160 	0x75, 0x03,		/*   REPORT SIZE (3)            */
161 	0x91, 0x01,		/*   OUTPUT (Constant)          */
162 	0xC0
163 };
164 
165 /* Mouse descriptor (2)     */
166 static const char mse_descriptor[] = {
167 	0x05, 0x01,		/*  USAGE_PAGE (Generic Desktop)        */
168 	0x09, 0x02,		/*  USAGE (Mouse)                       */
169 	0xA1, 0x01,		/*  COLLECTION (Application)            */
170 	0x85, 0x02,		/*    REPORT_ID = 2                     */
171 	0x09, 0x01,		/*    USAGE (pointer)                   */
172 	0xA1, 0x00,		/*    COLLECTION (physical)             */
173 	0x05, 0x09,		/*      USAGE_PAGE (buttons)            */
174 	0x19, 0x01,		/*      USAGE_MIN (1)                   */
175 	0x29, 0x10,		/*      USAGE_MAX (16)                  */
176 	0x15, 0x00,		/*      LOGICAL_MIN (0)                 */
177 	0x25, 0x01,		/*      LOGICAL_MAX (1)                 */
178 	0x95, 0x10,		/*      REPORT_COUNT (16)               */
179 	0x75, 0x01,		/*      REPORT_SIZE (1)                 */
180 	0x81, 0x02,		/*      INPUT (data var abs)            */
181 	0x05, 0x01,		/*      USAGE_PAGE (generic desktop)    */
182 	0x16, 0x01, 0xF8,	/*      LOGICAL_MIN (-2047)             */
183 	0x26, 0xFF, 0x07,	/*      LOGICAL_MAX (2047)              */
184 	0x75, 0x0C,		/*      REPORT_SIZE (12)                */
185 	0x95, 0x02,		/*      REPORT_COUNT (2)                */
186 	0x09, 0x30,		/*      USAGE (X)                       */
187 	0x09, 0x31,		/*      USAGE (Y)                       */
188 	0x81, 0x06,		/*      INPUT                           */
189 	0x15, 0x81,		/*      LOGICAL_MIN (-127)              */
190 	0x25, 0x7F,		/*      LOGICAL_MAX (127)               */
191 	0x75, 0x08,		/*      REPORT_SIZE (8)                 */
192 	0x95, 0x01,		/*      REPORT_COUNT (1)                */
193 	0x09, 0x38,		/*      USAGE (wheel)                   */
194 	0x81, 0x06,		/*      INPUT                           */
195 	0x05, 0x0C,		/*      USAGE_PAGE(consumer)            */
196 	0x0A, 0x38, 0x02,	/*      USAGE(AC Pan)                   */
197 	0x95, 0x01,		/*      REPORT_COUNT (1)                */
198 	0x81, 0x06,		/*      INPUT                           */
199 	0xC0,			/*    END_COLLECTION                    */
200 	0xC0,			/*  END_COLLECTION                      */
201 };
202 
203 /* Consumer Control descriptor (3) */
204 static const char consumer_descriptor[] = {
205 	0x05, 0x0C,		/* USAGE_PAGE (Consumer Devices)       */
206 	0x09, 0x01,		/* USAGE (Consumer Control)            */
207 	0xA1, 0x01,		/* COLLECTION (Application)            */
208 	0x85, 0x03,		/* REPORT_ID = 3                       */
209 	0x75, 0x10,		/* REPORT_SIZE (16)                    */
210 	0x95, 0x02,		/* REPORT_COUNT (2)                    */
211 	0x15, 0x01,		/* LOGICAL_MIN (1)                     */
212 	0x26, 0x8C, 0x02,	/* LOGICAL_MAX (652)                   */
213 	0x19, 0x01,		/* USAGE_MIN (1)                       */
214 	0x2A, 0x8C, 0x02,	/* USAGE_MAX (652)                     */
215 	0x81, 0x00,		/* INPUT (Data Ary Abs)                */
216 	0xC0,			/* END_COLLECTION                      */
217 };				/*                                     */
218 
219 /* System control descriptor (4) */
220 static const char syscontrol_descriptor[] = {
221 	0x05, 0x01,		/*   USAGE_PAGE (Generic Desktop)      */
222 	0x09, 0x80,		/*   USAGE (System Control)            */
223 	0xA1, 0x01,		/*   COLLECTION (Application)          */
224 	0x85, 0x04,		/*   REPORT_ID = 4                     */
225 	0x75, 0x02,		/*   REPORT_SIZE (2)                   */
226 	0x95, 0x01,		/*   REPORT_COUNT (1)                  */
227 	0x15, 0x01,		/*   LOGICAL_MIN (1)                   */
228 	0x25, 0x03,		/*   LOGICAL_MAX (3)                   */
229 	0x09, 0x82,		/*   USAGE (System Sleep)              */
230 	0x09, 0x81,		/*   USAGE (System Power Down)         */
231 	0x09, 0x83,		/*   USAGE (System Wake Up)            */
232 	0x81, 0x60,		/*   INPUT (Data Ary Abs NPrf Null)    */
233 	0x75, 0x06,		/*   REPORT_SIZE (6)                   */
234 	0x81, 0x03,		/*   INPUT (Cnst Var Abs)              */
235 	0xC0,			/*   END_COLLECTION                    */
236 };
237 
238 /* Media descriptor (8) */
239 static const char media_descriptor[] = {
240 	0x06, 0xbc, 0xff,	/* Usage Page 0xffbc                   */
241 	0x09, 0x88,		/* Usage 0x0088                        */
242 	0xa1, 0x01,		/* BeginCollection                     */
243 	0x85, 0x08,		/*   Report ID 8                       */
244 	0x19, 0x01,		/*   Usage Min 0x0001                  */
245 	0x29, 0xff,		/*   Usage Max 0x00ff                  */
246 	0x15, 0x01,		/*   Logical Min 1                     */
247 	0x26, 0xff, 0x00,	/*   Logical Max 255                   */
248 	0x75, 0x08,		/*   Report Size 8                     */
249 	0x95, 0x01,		/*   Report Count 1                    */
250 	0x81, 0x00,		/*   Input                             */
251 	0xc0,			/* EndCollection                       */
252 };				/*                                     */
253 
254 /* HIDPP descriptor */
255 static const char hidpp_descriptor[] = {
256 	0x06, 0x00, 0xff,	/* Usage Page (Vendor Defined Page 1)  */
257 	0x09, 0x01,		/* Usage (Vendor Usage 1)              */
258 	0xa1, 0x01,		/* Collection (Application)            */
259 	0x85, 0x10,		/*   Report ID (16)                    */
260 	0x75, 0x08,		/*   Report Size (8)                   */
261 	0x95, 0x06,		/*   Report Count (6)                  */
262 	0x15, 0x00,		/*   Logical Minimum (0)               */
263 	0x26, 0xff, 0x00,	/*   Logical Maximum (255)             */
264 	0x09, 0x01,		/*   Usage (Vendor Usage 1)            */
265 	0x81, 0x00,		/*   Input (Data,Arr,Abs)              */
266 	0x09, 0x01,		/*   Usage (Vendor Usage 1)            */
267 	0x91, 0x00,		/*   Output (Data,Arr,Abs)             */
268 	0xc0,			/* End Collection                      */
269 	0x06, 0x00, 0xff,	/* Usage Page (Vendor Defined Page 1)  */
270 	0x09, 0x02,		/* Usage (Vendor Usage 2)              */
271 	0xa1, 0x01,		/* Collection (Application)            */
272 	0x85, 0x11,		/*   Report ID (17)                    */
273 	0x75, 0x08,		/*   Report Size (8)                   */
274 	0x95, 0x13,		/*   Report Count (19)                 */
275 	0x15, 0x00,		/*   Logical Minimum (0)               */
276 	0x26, 0xff, 0x00,	/*   Logical Maximum (255)             */
277 	0x09, 0x02,		/*   Usage (Vendor Usage 2)            */
278 	0x81, 0x00,		/*   Input (Data,Arr,Abs)              */
279 	0x09, 0x02,		/*   Usage (Vendor Usage 2)            */
280 	0x91, 0x00,		/*   Output (Data,Arr,Abs)             */
281 	0xc0,			/* End Collection                      */
282 	0x06, 0x00, 0xff,	/* Usage Page (Vendor Defined Page 1)  */
283 	0x09, 0x04,		/* Usage (Vendor Usage 0x04)           */
284 	0xa1, 0x01,		/* Collection (Application)            */
285 	0x85, 0x20,		/*   Report ID (32)                    */
286 	0x75, 0x08,		/*   Report Size (8)                   */
287 	0x95, 0x0e,		/*   Report Count (14)                 */
288 	0x15, 0x00,		/*   Logical Minimum (0)               */
289 	0x26, 0xff, 0x00,	/*   Logical Maximum (255)             */
290 	0x09, 0x41,		/*   Usage (Vendor Usage 0x41)         */
291 	0x81, 0x00,		/*   Input (Data,Arr,Abs)              */
292 	0x09, 0x41,		/*   Usage (Vendor Usage 0x41)         */
293 	0x91, 0x00,		/*   Output (Data,Arr,Abs)             */
294 	0x85, 0x21,		/*   Report ID (33)                    */
295 	0x95, 0x1f,		/*   Report Count (31)                 */
296 	0x15, 0x00,		/*   Logical Minimum (0)               */
297 	0x26, 0xff, 0x00,	/*   Logical Maximum (255)             */
298 	0x09, 0x42,		/*   Usage (Vendor Usage 0x42)         */
299 	0x81, 0x00,		/*   Input (Data,Arr,Abs)              */
300 	0x09, 0x42,		/*   Usage (Vendor Usage 0x42)         */
301 	0x91, 0x00,		/*   Output (Data,Arr,Abs)             */
302 	0xc0,			/* End Collection                      */
303 };
304 
305 /* Maximum size of all defined hid reports in bytes (including report id) */
306 #define MAX_REPORT_SIZE 8
307 
308 /* Make sure all descriptors are present here */
309 #define MAX_RDESC_SIZE				\
310 	(sizeof(kbd_descriptor) +		\
311 	 sizeof(mse_descriptor) +		\
312 	 sizeof(consumer_descriptor) +		\
313 	 sizeof(syscontrol_descriptor) +	\
314 	 sizeof(media_descriptor) +	\
315 	 sizeof(hidpp_descriptor))
316 
317 /* Number of possible hid report types that can be created by this driver.
318  *
319  * Right now, RF report types have the same report types (or report id's)
320  * than the hid report created from those RF reports. In the future
321  * this doesnt have to be true.
322  *
323  * For instance, RF report type 0x01 which has a size of 8 bytes, corresponds
324  * to hid report id 0x01, this is standard keyboard. Same thing applies to mice
325  * reports and consumer control, etc. If a new RF report is created, it doesn't
326  * has to have the same report id as its corresponding hid report, so an
327  * translation may have to take place for future report types.
328  */
329 #define NUMBER_OF_HID_REPORTS 32
330 static const u8 hid_reportid_size_map[NUMBER_OF_HID_REPORTS] = {
331 	[1] = 8,		/* Standard keyboard */
332 	[2] = 8,		/* Standard mouse */
333 	[3] = 5,		/* Consumer control */
334 	[4] = 2,		/* System control */
335 	[8] = 2,		/* Media Center */
336 };
337 
338 
339 #define LOGITECH_DJ_INTERFACE_NUMBER 0x02
340 
341 static struct hid_ll_driver logi_dj_ll_driver;
342 
343 static int logi_dj_recv_query_paired_devices(struct dj_receiver_dev *djrcv_dev);
344 
345 static void logi_dj_recv_destroy_djhid_device(struct dj_receiver_dev *djrcv_dev,
346 						struct dj_report *dj_report)
347 {
348 	/* Called in delayed work context */
349 	struct dj_device *dj_dev;
350 	unsigned long flags;
351 
352 	spin_lock_irqsave(&djrcv_dev->lock, flags);
353 	dj_dev = djrcv_dev->paired_dj_devices[dj_report->device_index];
354 	djrcv_dev->paired_dj_devices[dj_report->device_index] = NULL;
355 	spin_unlock_irqrestore(&djrcv_dev->lock, flags);
356 
357 	if (dj_dev != NULL) {
358 		hid_destroy_device(dj_dev->hdev);
359 		kfree(dj_dev);
360 	} else {
361 		dev_err(&djrcv_dev->hdev->dev, "%s: can't destroy a NULL device\n",
362 			__func__);
363 	}
364 }
365 
366 static void logi_dj_recv_add_djhid_device(struct dj_receiver_dev *djrcv_dev,
367 					  struct dj_report *dj_report)
368 {
369 	/* Called in delayed work context */
370 	struct hid_device *djrcv_hdev = djrcv_dev->hdev;
371 	struct usb_interface *intf = to_usb_interface(djrcv_hdev->dev.parent);
372 	struct usb_device *usbdev = interface_to_usbdev(intf);
373 	struct hid_device *dj_hiddev;
374 	struct dj_device *dj_dev;
375 
376 	/* Device index goes from 1 to 6, we need 3 bytes to store the
377 	 * semicolon, the index, and a null terminator
378 	 */
379 	unsigned char tmpstr[3];
380 
381 	if (dj_report->report_params[DEVICE_PAIRED_PARAM_SPFUNCTION] &
382 	    SPFUNCTION_DEVICE_LIST_EMPTY) {
383 		dbg_hid("%s: device list is empty\n", __func__);
384 		djrcv_dev->querying_devices = false;
385 		return;
386 	}
387 
388 	if (djrcv_dev->paired_dj_devices[dj_report->device_index]) {
389 		/* The device is already known. No need to reallocate it. */
390 		dbg_hid("%s: device is already known\n", __func__);
391 		return;
392 	}
393 
394 	dj_hiddev = hid_allocate_device();
395 	if (IS_ERR(dj_hiddev)) {
396 		dev_err(&djrcv_hdev->dev, "%s: hid_allocate_device failed\n",
397 			__func__);
398 		return;
399 	}
400 
401 	dj_hiddev->ll_driver = &logi_dj_ll_driver;
402 
403 	dj_hiddev->dev.parent = &djrcv_hdev->dev;
404 	dj_hiddev->bus = BUS_USB;
405 	dj_hiddev->vendor = le16_to_cpu(usbdev->descriptor.idVendor);
406 	dj_hiddev->product =
407 		(dj_report->report_params[DEVICE_PAIRED_PARAM_EQUAD_ID_MSB]
408 									<< 8) |
409 		dj_report->report_params[DEVICE_PAIRED_PARAM_EQUAD_ID_LSB];
410 	snprintf(dj_hiddev->name, sizeof(dj_hiddev->name),
411 		"Logitech Unifying Device. Wireless PID:%04x",
412 		dj_hiddev->product);
413 
414 	dj_hiddev->group = HID_GROUP_LOGITECH_DJ_DEVICE;
415 
416 	usb_make_path(usbdev, dj_hiddev->phys, sizeof(dj_hiddev->phys));
417 	snprintf(tmpstr, sizeof(tmpstr), ":%d", dj_report->device_index);
418 	strlcat(dj_hiddev->phys, tmpstr, sizeof(dj_hiddev->phys));
419 
420 	dj_dev = kzalloc(sizeof(struct dj_device), GFP_KERNEL);
421 
422 	if (!dj_dev) {
423 		dev_err(&djrcv_hdev->dev, "%s: failed allocating dj_device\n",
424 			__func__);
425 		goto dj_device_allocate_fail;
426 	}
427 
428 	dj_dev->reports_supported = get_unaligned_le32(
429 		dj_report->report_params + DEVICE_PAIRED_RF_REPORT_TYPE);
430 	dj_dev->hdev = dj_hiddev;
431 	dj_dev->dj_receiver_dev = djrcv_dev;
432 	dj_dev->device_index = dj_report->device_index;
433 	dj_hiddev->driver_data = dj_dev;
434 
435 	djrcv_dev->paired_dj_devices[dj_report->device_index] = dj_dev;
436 
437 	if (hid_add_device(dj_hiddev)) {
438 		dev_err(&djrcv_hdev->dev, "%s: failed adding dj_device\n",
439 			__func__);
440 		goto hid_add_device_fail;
441 	}
442 
443 	return;
444 
445 hid_add_device_fail:
446 	djrcv_dev->paired_dj_devices[dj_report->device_index] = NULL;
447 	kfree(dj_dev);
448 dj_device_allocate_fail:
449 	hid_destroy_device(dj_hiddev);
450 }
451 
452 static void delayedwork_callback(struct work_struct *work)
453 {
454 	struct dj_receiver_dev *djrcv_dev =
455 		container_of(work, struct dj_receiver_dev, work);
456 
457 	struct dj_report dj_report;
458 	unsigned long flags;
459 	int count;
460 	int retval;
461 
462 	dbg_hid("%s\n", __func__);
463 
464 	spin_lock_irqsave(&djrcv_dev->lock, flags);
465 
466 	count = kfifo_out(&djrcv_dev->notif_fifo, &dj_report,
467 				sizeof(struct dj_report));
468 
469 	if (count != sizeof(struct dj_report)) {
470 		dev_err(&djrcv_dev->hdev->dev, "%s: workitem triggered without "
471 			"notifications available\n", __func__);
472 		spin_unlock_irqrestore(&djrcv_dev->lock, flags);
473 		return;
474 	}
475 
476 	if (!kfifo_is_empty(&djrcv_dev->notif_fifo)) {
477 		if (schedule_work(&djrcv_dev->work) == 0) {
478 			dbg_hid("%s: did not schedule the work item, was "
479 				"already queued\n", __func__);
480 		}
481 	}
482 
483 	spin_unlock_irqrestore(&djrcv_dev->lock, flags);
484 
485 	switch (dj_report.report_type) {
486 	case REPORT_TYPE_NOTIF_DEVICE_PAIRED:
487 		logi_dj_recv_add_djhid_device(djrcv_dev, &dj_report);
488 		break;
489 	case REPORT_TYPE_NOTIF_DEVICE_UNPAIRED:
490 		logi_dj_recv_destroy_djhid_device(djrcv_dev, &dj_report);
491 		break;
492 	default:
493 	/* A normal report (i. e. not belonging to a pair/unpair notification)
494 	 * arriving here, means that the report arrived but we did not have a
495 	 * paired dj_device associated to the report's device_index, this
496 	 * means that the original "device paired" notification corresponding
497 	 * to this dj_device never arrived to this driver. The reason is that
498 	 * hid-core discards all packets coming from a device while probe() is
499 	 * executing. */
500 	if (!djrcv_dev->paired_dj_devices[dj_report.device_index]) {
501 		/* ok, we don't know the device, just re-ask the
502 		 * receiver for the list of connected devices. */
503 		retval = logi_dj_recv_query_paired_devices(djrcv_dev);
504 		if (!retval) {
505 			/* everything went fine, so just leave */
506 			break;
507 		}
508 		dev_err(&djrcv_dev->hdev->dev,
509 			"%s:logi_dj_recv_query_paired_devices "
510 			"error:%d\n", __func__, retval);
511 		}
512 		dbg_hid("%s: unexpected report type\n", __func__);
513 	}
514 }
515 
516 static void logi_dj_recv_queue_notification(struct dj_receiver_dev *djrcv_dev,
517 					   struct dj_report *dj_report)
518 {
519 	/* We are called from atomic context (tasklet && djrcv->lock held) */
520 
521 	kfifo_in(&djrcv_dev->notif_fifo, dj_report, sizeof(struct dj_report));
522 
523 	if (schedule_work(&djrcv_dev->work) == 0) {
524 		dbg_hid("%s: did not schedule the work item, was already "
525 			"queued\n", __func__);
526 	}
527 }
528 
529 static void logi_dj_recv_forward_null_report(struct dj_receiver_dev *djrcv_dev,
530 					     struct dj_report *dj_report)
531 {
532 	/* We are called from atomic context (tasklet && djrcv->lock held) */
533 	unsigned int i;
534 	u8 reportbuffer[MAX_REPORT_SIZE];
535 	struct dj_device *djdev;
536 
537 	djdev = djrcv_dev->paired_dj_devices[dj_report->device_index];
538 
539 	memset(reportbuffer, 0, sizeof(reportbuffer));
540 
541 	for (i = 0; i < NUMBER_OF_HID_REPORTS; i++) {
542 		if (djdev->reports_supported & (1 << i)) {
543 			reportbuffer[0] = i;
544 			if (hid_input_report(djdev->hdev,
545 					     HID_INPUT_REPORT,
546 					     reportbuffer,
547 					     hid_reportid_size_map[i], 1)) {
548 				dbg_hid("hid_input_report error sending null "
549 					"report\n");
550 			}
551 		}
552 	}
553 }
554 
555 static void logi_dj_recv_forward_report(struct dj_receiver_dev *djrcv_dev,
556 					struct dj_report *dj_report)
557 {
558 	/* We are called from atomic context (tasklet && djrcv->lock held) */
559 	struct dj_device *dj_device;
560 
561 	dj_device = djrcv_dev->paired_dj_devices[dj_report->device_index];
562 
563 	if ((dj_report->report_type > ARRAY_SIZE(hid_reportid_size_map) - 1) ||
564 	    (hid_reportid_size_map[dj_report->report_type] == 0)) {
565 		dbg_hid("invalid report type:%x\n", dj_report->report_type);
566 		return;
567 	}
568 
569 	if (hid_input_report(dj_device->hdev,
570 			HID_INPUT_REPORT, &dj_report->report_type,
571 			hid_reportid_size_map[dj_report->report_type], 1)) {
572 		dbg_hid("hid_input_report error\n");
573 	}
574 }
575 
576 static void logi_dj_recv_forward_hidpp(struct dj_device *dj_dev, u8 *data,
577 				       int size)
578 {
579 	/* We are called from atomic context (tasklet && djrcv->lock held) */
580 	if (hid_input_report(dj_dev->hdev, HID_INPUT_REPORT, data, size, 1))
581 		dbg_hid("hid_input_report error\n");
582 }
583 
584 static int logi_dj_recv_send_report(struct dj_receiver_dev *djrcv_dev,
585 				    struct dj_report *dj_report)
586 {
587 	struct hid_device *hdev = djrcv_dev->hdev;
588 	struct hid_report *report;
589 	struct hid_report_enum *output_report_enum;
590 	u8 *data = (u8 *)(&dj_report->device_index);
591 	unsigned int i;
592 
593 	output_report_enum = &hdev->report_enum[HID_OUTPUT_REPORT];
594 	report = output_report_enum->report_id_hash[REPORT_ID_DJ_SHORT];
595 
596 	if (!report) {
597 		dev_err(&hdev->dev, "%s: unable to find dj report\n", __func__);
598 		return -ENODEV;
599 	}
600 
601 	for (i = 0; i < DJREPORT_SHORT_LENGTH - 1; i++)
602 		report->field[0]->value[i] = data[i];
603 
604 	hid_hw_request(hdev, report, HID_REQ_SET_REPORT);
605 
606 	return 0;
607 }
608 
609 static int logi_dj_recv_query_paired_devices(struct dj_receiver_dev *djrcv_dev)
610 {
611 	struct dj_report *dj_report;
612 	int retval;
613 
614 	/* no need to protect djrcv_dev->querying_devices */
615 	if (djrcv_dev->querying_devices)
616 		return 0;
617 
618 	dj_report = kzalloc(sizeof(struct dj_report), GFP_KERNEL);
619 	if (!dj_report)
620 		return -ENOMEM;
621 	dj_report->report_id = REPORT_ID_DJ_SHORT;
622 	dj_report->device_index = 0xFF;
623 	dj_report->report_type = REPORT_TYPE_CMD_GET_PAIRED_DEVICES;
624 	retval = logi_dj_recv_send_report(djrcv_dev, dj_report);
625 	kfree(dj_report);
626 	return retval;
627 }
628 
629 
630 static int logi_dj_recv_switch_to_dj_mode(struct dj_receiver_dev *djrcv_dev,
631 					  unsigned timeout)
632 {
633 	struct hid_device *hdev = djrcv_dev->hdev;
634 	struct dj_report *dj_report;
635 	u8 *buf;
636 	int retval;
637 
638 	dj_report = kzalloc(sizeof(struct dj_report), GFP_KERNEL);
639 	if (!dj_report)
640 		return -ENOMEM;
641 	dj_report->report_id = REPORT_ID_DJ_SHORT;
642 	dj_report->device_index = 0xFF;
643 	dj_report->report_type = REPORT_TYPE_CMD_SWITCH;
644 	dj_report->report_params[CMD_SWITCH_PARAM_DEVBITFIELD] = 0x3F;
645 	dj_report->report_params[CMD_SWITCH_PARAM_TIMEOUT_SECONDS] = (u8)timeout;
646 	retval = logi_dj_recv_send_report(djrcv_dev, dj_report);
647 
648 	/*
649 	 * Ugly sleep to work around a USB 3.0 bug when the receiver is still
650 	 * processing the "switch-to-dj" command while we send an other command.
651 	 * 50 msec should gives enough time to the receiver to be ready.
652 	 */
653 	msleep(50);
654 
655 	/*
656 	 * Magical bits to set up hidpp notifications when the dj devices
657 	 * are connected/disconnected.
658 	 *
659 	 * We can reuse dj_report because HIDPP_REPORT_SHORT_LENGTH is smaller
660 	 * than DJREPORT_SHORT_LENGTH.
661 	 */
662 	buf = (u8 *)dj_report;
663 
664 	memset(buf, 0, HIDPP_REPORT_SHORT_LENGTH);
665 
666 	buf[0] = REPORT_ID_HIDPP_SHORT;
667 	buf[1] = 0xFF;
668 	buf[2] = 0x80;
669 	buf[3] = 0x00;
670 	buf[4] = 0x00;
671 	buf[5] = 0x09;
672 	buf[6] = 0x00;
673 
674 	hid_hw_raw_request(hdev, REPORT_ID_HIDPP_SHORT, buf,
675 			HIDPP_REPORT_SHORT_LENGTH, HID_OUTPUT_REPORT,
676 			HID_REQ_SET_REPORT);
677 
678 	kfree(dj_report);
679 	return retval;
680 }
681 
682 
683 static int logi_dj_ll_open(struct hid_device *hid)
684 {
685 	dbg_hid("%s:%s\n", __func__, hid->phys);
686 	return 0;
687 
688 }
689 
690 static void logi_dj_ll_close(struct hid_device *hid)
691 {
692 	dbg_hid("%s:%s\n", __func__, hid->phys);
693 }
694 
695 static u8 unifying_name_query[]  = {0x10, 0xff, 0x83, 0xb5, 0x40, 0x00, 0x00};
696 static u8 unifying_name_answer[] = {0x11, 0xff, 0x83, 0xb5};
697 
698 static int logi_dj_ll_raw_request(struct hid_device *hid,
699 				  unsigned char reportnum, __u8 *buf,
700 				  size_t count, unsigned char report_type,
701 				  int reqtype)
702 {
703 	struct dj_device *djdev = hid->driver_data;
704 	struct dj_receiver_dev *djrcv_dev = djdev->dj_receiver_dev;
705 	u8 *out_buf;
706 	int ret;
707 
708 	if ((buf[0] == REPORT_ID_HIDPP_SHORT) ||
709 	    (buf[0] == REPORT_ID_HIDPP_LONG)) {
710 		if (count < 2)
711 			return -EINVAL;
712 
713 		/* special case where we should not overwrite
714 		 * the device_index */
715 		if (count == 7 && !memcmp(buf, unifying_name_query,
716 					  sizeof(unifying_name_query)))
717 			buf[4] |= djdev->device_index - 1;
718 		else
719 			buf[1] = djdev->device_index;
720 		return hid_hw_raw_request(djrcv_dev->hdev, reportnum, buf,
721 				count, report_type, reqtype);
722 	}
723 
724 	if (buf[0] != REPORT_TYPE_LEDS)
725 		return -EINVAL;
726 
727 	out_buf = kzalloc(DJREPORT_SHORT_LENGTH, GFP_ATOMIC);
728 	if (!out_buf)
729 		return -ENOMEM;
730 
731 	if (count > DJREPORT_SHORT_LENGTH - 2)
732 		count = DJREPORT_SHORT_LENGTH - 2;
733 
734 	out_buf[0] = REPORT_ID_DJ_SHORT;
735 	out_buf[1] = djdev->device_index;
736 	memcpy(out_buf + 2, buf, count);
737 
738 	ret = hid_hw_raw_request(djrcv_dev->hdev, out_buf[0], out_buf,
739 		DJREPORT_SHORT_LENGTH, report_type, reqtype);
740 
741 	kfree(out_buf);
742 	return ret;
743 }
744 
745 static void rdcat(char *rdesc, unsigned int *rsize, const char *data, unsigned int size)
746 {
747 	memcpy(rdesc + *rsize, data, size);
748 	*rsize += size;
749 }
750 
751 static int logi_dj_ll_parse(struct hid_device *hid)
752 {
753 	struct dj_device *djdev = hid->driver_data;
754 	unsigned int rsize = 0;
755 	char *rdesc;
756 	int retval;
757 
758 	dbg_hid("%s\n", __func__);
759 
760 	djdev->hdev->version = 0x0111;
761 	djdev->hdev->country = 0x00;
762 
763 	rdesc = kmalloc(MAX_RDESC_SIZE, GFP_KERNEL);
764 	if (!rdesc)
765 		return -ENOMEM;
766 
767 	if (djdev->reports_supported & STD_KEYBOARD) {
768 		dbg_hid("%s: sending a kbd descriptor, reports_supported: %x\n",
769 			__func__, djdev->reports_supported);
770 		rdcat(rdesc, &rsize, kbd_descriptor, sizeof(kbd_descriptor));
771 	}
772 
773 	if (djdev->reports_supported & STD_MOUSE) {
774 		dbg_hid("%s: sending a mouse descriptor, reports_supported: "
775 			"%x\n", __func__, djdev->reports_supported);
776 		rdcat(rdesc, &rsize, mse_descriptor, sizeof(mse_descriptor));
777 	}
778 
779 	if (djdev->reports_supported & MULTIMEDIA) {
780 		dbg_hid("%s: sending a multimedia report descriptor: %x\n",
781 			__func__, djdev->reports_supported);
782 		rdcat(rdesc, &rsize, consumer_descriptor, sizeof(consumer_descriptor));
783 	}
784 
785 	if (djdev->reports_supported & POWER_KEYS) {
786 		dbg_hid("%s: sending a power keys report descriptor: %x\n",
787 			__func__, djdev->reports_supported);
788 		rdcat(rdesc, &rsize, syscontrol_descriptor, sizeof(syscontrol_descriptor));
789 	}
790 
791 	if (djdev->reports_supported & MEDIA_CENTER) {
792 		dbg_hid("%s: sending a media center report descriptor: %x\n",
793 			__func__, djdev->reports_supported);
794 		rdcat(rdesc, &rsize, media_descriptor, sizeof(media_descriptor));
795 	}
796 
797 	if (djdev->reports_supported & KBD_LEDS) {
798 		dbg_hid("%s: need to send kbd leds report descriptor: %x\n",
799 			__func__, djdev->reports_supported);
800 	}
801 
802 	rdcat(rdesc, &rsize, hidpp_descriptor, sizeof(hidpp_descriptor));
803 
804 	retval = hid_parse_report(hid, rdesc, rsize);
805 	kfree(rdesc);
806 
807 	return retval;
808 }
809 
810 static int logi_dj_ll_start(struct hid_device *hid)
811 {
812 	dbg_hid("%s\n", __func__);
813 	return 0;
814 }
815 
816 static void logi_dj_ll_stop(struct hid_device *hid)
817 {
818 	dbg_hid("%s\n", __func__);
819 }
820 
821 
822 static struct hid_ll_driver logi_dj_ll_driver = {
823 	.parse = logi_dj_ll_parse,
824 	.start = logi_dj_ll_start,
825 	.stop = logi_dj_ll_stop,
826 	.open = logi_dj_ll_open,
827 	.close = logi_dj_ll_close,
828 	.raw_request = logi_dj_ll_raw_request,
829 };
830 
831 static int logi_dj_dj_event(struct hid_device *hdev,
832 			     struct hid_report *report, u8 *data,
833 			     int size)
834 {
835 	struct dj_receiver_dev *djrcv_dev = hid_get_drvdata(hdev);
836 	struct dj_report *dj_report = (struct dj_report *) data;
837 	unsigned long flags;
838 
839 	/*
840 	 * Here we receive all data coming from iface 2, there are 3 cases:
841 	 *
842 	 * 1) Data is intended for this driver i. e. data contains arrival,
843 	 * departure, etc notifications, in which case we queue them for delayed
844 	 * processing by the work queue. We return 1 to hid-core as no further
845 	 * processing is required from it.
846 	 *
847 	 * 2) Data informs a connection change, if the change means rf link
848 	 * loss, then we must send a null report to the upper layer to discard
849 	 * potentially pressed keys that may be repeated forever by the input
850 	 * layer. Return 1 to hid-core as no further processing is required.
851 	 *
852 	 * 3) Data is an actual input event from a paired DJ device in which
853 	 * case we forward it to the correct hid device (via hid_input_report()
854 	 * ) and return 1 so hid-core does not anything else with it.
855 	 */
856 
857 	if ((dj_report->device_index < DJ_DEVICE_INDEX_MIN) ||
858 	    (dj_report->device_index > DJ_DEVICE_INDEX_MAX)) {
859 		/*
860 		 * Device index is wrong, bail out.
861 		 * This driver can ignore safely the receiver notifications,
862 		 * so ignore those reports too.
863 		 */
864 		if (dj_report->device_index != DJ_RECEIVER_INDEX)
865 			dev_err(&hdev->dev, "%s: invalid device index:%d\n",
866 				__func__, dj_report->device_index);
867 		return false;
868 	}
869 
870 	spin_lock_irqsave(&djrcv_dev->lock, flags);
871 
872 	if (!djrcv_dev->paired_dj_devices[dj_report->device_index]) {
873 		/* received an event for an unknown device, bail out */
874 		logi_dj_recv_queue_notification(djrcv_dev, dj_report);
875 		goto out;
876 	}
877 
878 	switch (dj_report->report_type) {
879 	case REPORT_TYPE_NOTIF_DEVICE_PAIRED:
880 		/* pairing notifications are handled above the switch */
881 		break;
882 	case REPORT_TYPE_NOTIF_DEVICE_UNPAIRED:
883 		logi_dj_recv_queue_notification(djrcv_dev, dj_report);
884 		break;
885 	case REPORT_TYPE_NOTIF_CONNECTION_STATUS:
886 		if (dj_report->report_params[CONNECTION_STATUS_PARAM_STATUS] ==
887 		    STATUS_LINKLOSS) {
888 			logi_dj_recv_forward_null_report(djrcv_dev, dj_report);
889 		}
890 		break;
891 	default:
892 		logi_dj_recv_forward_report(djrcv_dev, dj_report);
893 	}
894 
895 out:
896 	spin_unlock_irqrestore(&djrcv_dev->lock, flags);
897 
898 	return true;
899 }
900 
901 static int logi_dj_hidpp_event(struct hid_device *hdev,
902 			     struct hid_report *report, u8 *data,
903 			     int size)
904 {
905 	struct dj_receiver_dev *djrcv_dev = hid_get_drvdata(hdev);
906 	struct dj_report *dj_report = (struct dj_report *) data;
907 	unsigned long flags;
908 	u8 device_index = dj_report->device_index;
909 
910 	if (device_index == HIDPP_RECEIVER_INDEX) {
911 		/* special case were the device wants to know its unifying
912 		 * name */
913 		if (size == HIDPP_REPORT_LONG_LENGTH &&
914 		    !memcmp(data, unifying_name_answer,
915 			    sizeof(unifying_name_answer)) &&
916 		    ((data[4] & 0xF0) == 0x40))
917 			device_index = (data[4] & 0x0F) + 1;
918 		else
919 			return false;
920 	}
921 
922 	/*
923 	 * Data is from the HID++ collection, in this case, we forward the
924 	 * data to the corresponding child dj device and return 0 to hid-core
925 	 * so he data also goes to the hidraw device of the receiver. This
926 	 * allows a user space application to implement the full HID++ routing
927 	 * via the receiver.
928 	 */
929 
930 	if ((device_index < DJ_DEVICE_INDEX_MIN) ||
931 	    (device_index > DJ_DEVICE_INDEX_MAX)) {
932 		/*
933 		 * Device index is wrong, bail out.
934 		 * This driver can ignore safely the receiver notifications,
935 		 * so ignore those reports too.
936 		 */
937 		dev_err(&hdev->dev, "%s: invalid device index:%d\n",
938 				__func__, dj_report->device_index);
939 		return false;
940 	}
941 
942 	spin_lock_irqsave(&djrcv_dev->lock, flags);
943 
944 	if (!djrcv_dev->paired_dj_devices[device_index])
945 		/* received an event for an unknown device, bail out */
946 		goto out;
947 
948 	logi_dj_recv_forward_hidpp(djrcv_dev->paired_dj_devices[device_index],
949 				   data, size);
950 
951 out:
952 	spin_unlock_irqrestore(&djrcv_dev->lock, flags);
953 
954 	return false;
955 }
956 
957 static int logi_dj_raw_event(struct hid_device *hdev,
958 			     struct hid_report *report, u8 *data,
959 			     int size)
960 {
961 	dbg_hid("%s, size:%d\n", __func__, size);
962 
963 	switch (data[0]) {
964 	case REPORT_ID_DJ_SHORT:
965 		if (size != DJREPORT_SHORT_LENGTH) {
966 			dev_err(&hdev->dev, "DJ report of bad size (%d)", size);
967 			return false;
968 		}
969 		return logi_dj_dj_event(hdev, report, data, size);
970 	case REPORT_ID_HIDPP_SHORT:
971 		if (size != HIDPP_REPORT_SHORT_LENGTH) {
972 			dev_err(&hdev->dev,
973 				"Short HID++ report of bad size (%d)", size);
974 			return false;
975 		}
976 		return logi_dj_hidpp_event(hdev, report, data, size);
977 	case REPORT_ID_HIDPP_LONG:
978 		if (size != HIDPP_REPORT_LONG_LENGTH) {
979 			dev_err(&hdev->dev,
980 				"Long HID++ report of bad size (%d)", size);
981 			return false;
982 		}
983 		return logi_dj_hidpp_event(hdev, report, data, size);
984 	}
985 
986 	return false;
987 }
988 
989 static int logi_dj_probe(struct hid_device *hdev,
990 			 const struct hid_device_id *id)
991 {
992 	struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
993 	struct dj_receiver_dev *djrcv_dev;
994 	int retval;
995 
996 	dbg_hid("%s called for ifnum %d\n", __func__,
997 		intf->cur_altsetting->desc.bInterfaceNumber);
998 
999 	/* Ignore interfaces 0 and 1, they will not carry any data, dont create
1000 	 * any hid_device for them */
1001 	if (intf->cur_altsetting->desc.bInterfaceNumber !=
1002 	    LOGITECH_DJ_INTERFACE_NUMBER) {
1003 		dbg_hid("%s: ignoring ifnum %d\n", __func__,
1004 			intf->cur_altsetting->desc.bInterfaceNumber);
1005 		return -ENODEV;
1006 	}
1007 
1008 	/* Treat interface 2 */
1009 
1010 	djrcv_dev = kzalloc(sizeof(struct dj_receiver_dev), GFP_KERNEL);
1011 	if (!djrcv_dev) {
1012 		dev_err(&hdev->dev,
1013 			"%s:failed allocating dj_receiver_dev\n", __func__);
1014 		return -ENOMEM;
1015 	}
1016 	djrcv_dev->hdev = hdev;
1017 	INIT_WORK(&djrcv_dev->work, delayedwork_callback);
1018 	spin_lock_init(&djrcv_dev->lock);
1019 	if (kfifo_alloc(&djrcv_dev->notif_fifo,
1020 			DJ_MAX_NUMBER_NOTIFICATIONS * sizeof(struct dj_report),
1021 			GFP_KERNEL)) {
1022 		dev_err(&hdev->dev,
1023 			"%s:failed allocating notif_fifo\n", __func__);
1024 		kfree(djrcv_dev);
1025 		return -ENOMEM;
1026 	}
1027 	hid_set_drvdata(hdev, djrcv_dev);
1028 
1029 	/* Call  to usbhid to fetch the HID descriptors of interface 2 and
1030 	 * subsequently call to the hid/hid-core to parse the fetched
1031 	 * descriptors, this will in turn create the hidraw and hiddev nodes
1032 	 * for interface 2 of the receiver */
1033 	retval = hid_parse(hdev);
1034 	if (retval) {
1035 		dev_err(&hdev->dev,
1036 			"%s:parse of interface 2 failed\n", __func__);
1037 		goto hid_parse_fail;
1038 	}
1039 
1040 	if (!hid_validate_values(hdev, HID_OUTPUT_REPORT, REPORT_ID_DJ_SHORT,
1041 				 0, DJREPORT_SHORT_LENGTH - 1)) {
1042 		retval = -ENODEV;
1043 		goto hid_parse_fail;
1044 	}
1045 
1046 	/* Starts the usb device and connects to upper interfaces hiddev and
1047 	 * hidraw */
1048 	retval = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
1049 	if (retval) {
1050 		dev_err(&hdev->dev,
1051 			"%s:hid_hw_start returned error\n", __func__);
1052 		goto hid_hw_start_fail;
1053 	}
1054 
1055 	retval = logi_dj_recv_switch_to_dj_mode(djrcv_dev, 0);
1056 	if (retval < 0) {
1057 		dev_err(&hdev->dev,
1058 			"%s:logi_dj_recv_switch_to_dj_mode returned error:%d\n",
1059 			__func__, retval);
1060 		goto switch_to_dj_mode_fail;
1061 	}
1062 
1063 	/* This is enabling the polling urb on the IN endpoint */
1064 	retval = hid_hw_open(hdev);
1065 	if (retval < 0) {
1066 		dev_err(&hdev->dev, "%s:hid_hw_open returned error:%d\n",
1067 			__func__, retval);
1068 		goto llopen_failed;
1069 	}
1070 
1071 	/* Allow incoming packets to arrive: */
1072 	hid_device_io_start(hdev);
1073 
1074 	retval = logi_dj_recv_query_paired_devices(djrcv_dev);
1075 	if (retval < 0) {
1076 		dev_err(&hdev->dev, "%s:logi_dj_recv_query_paired_devices "
1077 			"error:%d\n", __func__, retval);
1078 		goto logi_dj_recv_query_paired_devices_failed;
1079 	}
1080 
1081 	return retval;
1082 
1083 logi_dj_recv_query_paired_devices_failed:
1084 	hid_hw_close(hdev);
1085 
1086 llopen_failed:
1087 switch_to_dj_mode_fail:
1088 	hid_hw_stop(hdev);
1089 
1090 hid_hw_start_fail:
1091 hid_parse_fail:
1092 	kfifo_free(&djrcv_dev->notif_fifo);
1093 	kfree(djrcv_dev);
1094 	hid_set_drvdata(hdev, NULL);
1095 	return retval;
1096 
1097 }
1098 
1099 #ifdef CONFIG_PM
1100 static int logi_dj_reset_resume(struct hid_device *hdev)
1101 {
1102 	int retval;
1103 	struct dj_receiver_dev *djrcv_dev = hid_get_drvdata(hdev);
1104 
1105 	retval = logi_dj_recv_switch_to_dj_mode(djrcv_dev, 0);
1106 	if (retval < 0) {
1107 		dev_err(&hdev->dev,
1108 			"%s:logi_dj_recv_switch_to_dj_mode returned error:%d\n",
1109 			__func__, retval);
1110 	}
1111 
1112 	return 0;
1113 }
1114 #endif
1115 
1116 static void logi_dj_remove(struct hid_device *hdev)
1117 {
1118 	struct dj_receiver_dev *djrcv_dev = hid_get_drvdata(hdev);
1119 	struct dj_device *dj_dev;
1120 	int i;
1121 
1122 	dbg_hid("%s\n", __func__);
1123 
1124 	cancel_work_sync(&djrcv_dev->work);
1125 
1126 	hid_hw_close(hdev);
1127 	hid_hw_stop(hdev);
1128 
1129 	/* I suppose that at this point the only context that can access
1130 	 * the djrecv_data is this thread as the work item is guaranteed to
1131 	 * have finished and no more raw_event callbacks should arrive after
1132 	 * the remove callback was triggered so no locks are put around the
1133 	 * code below */
1134 	for (i = 0; i < (DJ_MAX_PAIRED_DEVICES + DJ_DEVICE_INDEX_MIN); i++) {
1135 		dj_dev = djrcv_dev->paired_dj_devices[i];
1136 		if (dj_dev != NULL) {
1137 			hid_destroy_device(dj_dev->hdev);
1138 			kfree(dj_dev);
1139 			djrcv_dev->paired_dj_devices[i] = NULL;
1140 		}
1141 	}
1142 
1143 	kfifo_free(&djrcv_dev->notif_fifo);
1144 	kfree(djrcv_dev);
1145 	hid_set_drvdata(hdev, NULL);
1146 }
1147 
1148 static const struct hid_device_id logi_dj_receivers[] = {
1149 	{HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH,
1150 		USB_DEVICE_ID_LOGITECH_UNIFYING_RECEIVER)},
1151 	{HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH,
1152 		USB_DEVICE_ID_LOGITECH_UNIFYING_RECEIVER_2)},
1153 	{}
1154 };
1155 
1156 MODULE_DEVICE_TABLE(hid, logi_dj_receivers);
1157 
1158 static struct hid_driver logi_djreceiver_driver = {
1159 	.name = "logitech-djreceiver",
1160 	.id_table = logi_dj_receivers,
1161 	.probe = logi_dj_probe,
1162 	.remove = logi_dj_remove,
1163 	.raw_event = logi_dj_raw_event,
1164 #ifdef CONFIG_PM
1165 	.reset_resume = logi_dj_reset_resume,
1166 #endif
1167 };
1168 
1169 module_hid_driver(logi_djreceiver_driver);
1170 
1171 MODULE_LICENSE("GPL");
1172 MODULE_AUTHOR("Logitech");
1173 MODULE_AUTHOR("Nestor Lopez Casado");
1174 MODULE_AUTHOR("nlopezcasad@logitech.com");
1175