xref: /openbmc/linux/drivers/media/rc/imon.c (revision 8795a739)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *   imon.c:	input and display driver for SoundGraph iMON IR/VFD/LCD
4  *
5  *   Copyright(C) 2010  Jarod Wilson <jarod@wilsonet.com>
6  *   Portions based on the original lirc_imon driver,
7  *	Copyright(C) 2004  Venky Raju(dev@venky.ws)
8  *
9  *   Huge thanks to R. Geoff Newbury for invaluable debugging on the
10  *   0xffdc iMON devices, and for sending me one to hack on, without
11  *   which the support for them wouldn't be nearly as good. Thanks
12  *   also to the numerous 0xffdc device owners that tested auto-config
13  *   support for me and provided debug dumps from their devices.
14  */
15 
16 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
17 
18 #include <linux/errno.h>
19 #include <linux/init.h>
20 #include <linux/kernel.h>
21 #include <linux/ktime.h>
22 #include <linux/module.h>
23 #include <linux/slab.h>
24 #include <linux/uaccess.h>
25 #include <linux/ratelimit.h>
26 
27 #include <linux/input.h>
28 #include <linux/usb.h>
29 #include <linux/usb/input.h>
30 #include <media/rc-core.h>
31 
32 #include <linux/timer.h>
33 
34 #define MOD_AUTHOR	"Jarod Wilson <jarod@wilsonet.com>"
35 #define MOD_DESC	"Driver for SoundGraph iMON MultiMedia IR/Display"
36 #define MOD_NAME	"imon"
37 #define MOD_VERSION	"0.9.4"
38 
39 #define DISPLAY_MINOR_BASE	144
40 #define DEVICE_NAME	"lcd%d"
41 
42 #define BUF_CHUNK_SIZE	8
43 #define BUF_SIZE	128
44 
45 #define BIT_DURATION	250	/* each bit received is 250us */
46 
47 #define IMON_CLOCK_ENABLE_PACKETS	2
48 
49 /*** P R O T O T Y P E S ***/
50 
51 /* USB Callback prototypes */
52 static int imon_probe(struct usb_interface *interface,
53 		      const struct usb_device_id *id);
54 static void imon_disconnect(struct usb_interface *interface);
55 static void usb_rx_callback_intf0(struct urb *urb);
56 static void usb_rx_callback_intf1(struct urb *urb);
57 static void usb_tx_callback(struct urb *urb);
58 
59 /* suspend/resume support */
60 static int imon_resume(struct usb_interface *intf);
61 static int imon_suspend(struct usb_interface *intf, pm_message_t message);
62 
63 /* Display file_operations function prototypes */
64 static int display_open(struct inode *inode, struct file *file);
65 static int display_close(struct inode *inode, struct file *file);
66 
67 /* VFD write operation */
68 static ssize_t vfd_write(struct file *file, const char __user *buf,
69 			 size_t n_bytes, loff_t *pos);
70 
71 /* LCD file_operations override function prototypes */
72 static ssize_t lcd_write(struct file *file, const char __user *buf,
73 			 size_t n_bytes, loff_t *pos);
74 
75 /*** G L O B A L S ***/
76 
77 struct imon_panel_key_table {
78 	u64 hw_code;
79 	u32 keycode;
80 };
81 
82 struct imon_usb_dev_descr {
83 	__u16 flags;
84 #define IMON_NO_FLAGS 0
85 #define IMON_NEED_20MS_PKT_DELAY 1
86 	struct imon_panel_key_table key_table[];
87 };
88 
89 struct imon_context {
90 	struct device *dev;
91 	/* Newer devices have two interfaces */
92 	struct usb_device *usbdev_intf0;
93 	struct usb_device *usbdev_intf1;
94 
95 	bool display_supported;		/* not all controllers do */
96 	bool display_isopen;		/* display port has been opened */
97 	bool rf_device;			/* true if iMON 2.4G LT/DT RF device */
98 	bool rf_isassociating;		/* RF remote associating */
99 	bool dev_present_intf0;		/* USB device presence, interface 0 */
100 	bool dev_present_intf1;		/* USB device presence, interface 1 */
101 
102 	struct mutex lock;		/* to lock this object */
103 	wait_queue_head_t remove_ok;	/* For unexpected USB disconnects */
104 
105 	struct usb_endpoint_descriptor *rx_endpoint_intf0;
106 	struct usb_endpoint_descriptor *rx_endpoint_intf1;
107 	struct usb_endpoint_descriptor *tx_endpoint;
108 	struct urb *rx_urb_intf0;
109 	struct urb *rx_urb_intf1;
110 	struct urb *tx_urb;
111 	bool tx_control;
112 	unsigned char usb_rx_buf[8];
113 	unsigned char usb_tx_buf[8];
114 	unsigned int send_packet_delay;
115 
116 	struct tx_t {
117 		unsigned char data_buf[35];	/* user data buffer */
118 		struct completion finished;	/* wait for write to finish */
119 		bool busy;			/* write in progress */
120 		int status;			/* status of tx completion */
121 	} tx;
122 
123 	u16 vendor;			/* usb vendor ID */
124 	u16 product;			/* usb product ID */
125 
126 	struct rc_dev *rdev;		/* rc-core device for remote */
127 	struct input_dev *idev;		/* input device for panel & IR mouse */
128 	struct input_dev *touch;	/* input device for touchscreen */
129 
130 	spinlock_t kc_lock;		/* make sure we get keycodes right */
131 	u32 kc;				/* current input keycode */
132 	u32 last_keycode;		/* last reported input keycode */
133 	u32 rc_scancode;		/* the computed remote scancode */
134 	u8 rc_toggle;			/* the computed remote toggle bit */
135 	u64 rc_proto;			/* iMON or MCE (RC6) IR protocol? */
136 	bool release_code;		/* some keys send a release code */
137 
138 	u8 display_type;		/* store the display type */
139 	bool pad_mouse;			/* toggle kbd(0)/mouse(1) mode */
140 
141 	char name_rdev[128];		/* rc input device name */
142 	char phys_rdev[64];		/* rc input device phys path */
143 
144 	char name_idev[128];		/* input device name */
145 	char phys_idev[64];		/* input device phys path */
146 
147 	char name_touch[128];		/* touch screen name */
148 	char phys_touch[64];		/* touch screen phys path */
149 	struct timer_list ttimer;	/* touch screen timer */
150 	int touch_x;			/* x coordinate on touchscreen */
151 	int touch_y;			/* y coordinate on touchscreen */
152 	struct imon_usb_dev_descr *dev_descr; /* device description with key
153 						 table for front panels */
154 };
155 
156 #define TOUCH_TIMEOUT	(HZ/30)
157 
158 /* vfd character device file operations */
159 static const struct file_operations vfd_fops = {
160 	.owner		= THIS_MODULE,
161 	.open		= &display_open,
162 	.write		= &vfd_write,
163 	.release	= &display_close,
164 	.llseek		= noop_llseek,
165 };
166 
167 /* lcd character device file operations */
168 static const struct file_operations lcd_fops = {
169 	.owner		= THIS_MODULE,
170 	.open		= &display_open,
171 	.write		= &lcd_write,
172 	.release	= &display_close,
173 	.llseek		= noop_llseek,
174 };
175 
176 enum {
177 	IMON_DISPLAY_TYPE_AUTO = 0,
178 	IMON_DISPLAY_TYPE_VFD  = 1,
179 	IMON_DISPLAY_TYPE_LCD  = 2,
180 	IMON_DISPLAY_TYPE_VGA  = 3,
181 	IMON_DISPLAY_TYPE_NONE = 4,
182 };
183 
184 enum {
185 	IMON_KEY_IMON	= 0,
186 	IMON_KEY_MCE	= 1,
187 	IMON_KEY_PANEL	= 2,
188 };
189 
190 static struct usb_class_driver imon_vfd_class = {
191 	.name		= DEVICE_NAME,
192 	.fops		= &vfd_fops,
193 	.minor_base	= DISPLAY_MINOR_BASE,
194 };
195 
196 static struct usb_class_driver imon_lcd_class = {
197 	.name		= DEVICE_NAME,
198 	.fops		= &lcd_fops,
199 	.minor_base	= DISPLAY_MINOR_BASE,
200 };
201 
202 /* imon receiver front panel/knob key table */
203 static const struct imon_usb_dev_descr imon_default_table = {
204 	.flags = IMON_NO_FLAGS,
205 	.key_table = {
206 		{ 0x000000000f00ffeell, KEY_MEDIA }, /* Go */
207 		{ 0x000000001200ffeell, KEY_UP },
208 		{ 0x000000001300ffeell, KEY_DOWN },
209 		{ 0x000000001400ffeell, KEY_LEFT },
210 		{ 0x000000001500ffeell, KEY_RIGHT },
211 		{ 0x000000001600ffeell, KEY_ENTER },
212 		{ 0x000000001700ffeell, KEY_ESC },
213 		{ 0x000000001f00ffeell, KEY_AUDIO },
214 		{ 0x000000002000ffeell, KEY_VIDEO },
215 		{ 0x000000002100ffeell, KEY_CAMERA },
216 		{ 0x000000002700ffeell, KEY_DVD },
217 		{ 0x000000002300ffeell, KEY_TV },
218 		{ 0x000000002b00ffeell, KEY_EXIT },
219 		{ 0x000000002c00ffeell, KEY_SELECT },
220 		{ 0x000000002d00ffeell, KEY_MENU },
221 		{ 0x000000000500ffeell, KEY_PREVIOUS },
222 		{ 0x000000000700ffeell, KEY_REWIND },
223 		{ 0x000000000400ffeell, KEY_STOP },
224 		{ 0x000000003c00ffeell, KEY_PLAYPAUSE },
225 		{ 0x000000000800ffeell, KEY_FASTFORWARD },
226 		{ 0x000000000600ffeell, KEY_NEXT },
227 		{ 0x000000010000ffeell, KEY_RIGHT },
228 		{ 0x000001000000ffeell, KEY_LEFT },
229 		{ 0x000000003d00ffeell, KEY_SELECT },
230 		{ 0x000100000000ffeell, KEY_VOLUMEUP },
231 		{ 0x010000000000ffeell, KEY_VOLUMEDOWN },
232 		{ 0x000000000100ffeell, KEY_MUTE },
233 		/* 0xffdc iMON MCE VFD */
234 		{ 0x00010000ffffffeell, KEY_VOLUMEUP },
235 		{ 0x01000000ffffffeell, KEY_VOLUMEDOWN },
236 		{ 0x00000001ffffffeell, KEY_MUTE },
237 		{ 0x0000000fffffffeell, KEY_MEDIA },
238 		{ 0x00000012ffffffeell, KEY_UP },
239 		{ 0x00000013ffffffeell, KEY_DOWN },
240 		{ 0x00000014ffffffeell, KEY_LEFT },
241 		{ 0x00000015ffffffeell, KEY_RIGHT },
242 		{ 0x00000016ffffffeell, KEY_ENTER },
243 		{ 0x00000017ffffffeell, KEY_ESC },
244 		/* iMON Knob values */
245 		{ 0x000100ffffffffeell, KEY_VOLUMEUP },
246 		{ 0x010000ffffffffeell, KEY_VOLUMEDOWN },
247 		{ 0x000008ffffffffeell, KEY_MUTE },
248 		{ 0, KEY_RESERVED },
249 	}
250 };
251 
252 static const struct imon_usb_dev_descr imon_OEM_VFD = {
253 	.flags = IMON_NEED_20MS_PKT_DELAY,
254 	.key_table = {
255 		{ 0x000000000f00ffeell, KEY_MEDIA }, /* Go */
256 		{ 0x000000001200ffeell, KEY_UP },
257 		{ 0x000000001300ffeell, KEY_DOWN },
258 		{ 0x000000001400ffeell, KEY_LEFT },
259 		{ 0x000000001500ffeell, KEY_RIGHT },
260 		{ 0x000000001600ffeell, KEY_ENTER },
261 		{ 0x000000001700ffeell, KEY_ESC },
262 		{ 0x000000001f00ffeell, KEY_AUDIO },
263 		{ 0x000000002b00ffeell, KEY_EXIT },
264 		{ 0x000000002c00ffeell, KEY_SELECT },
265 		{ 0x000000002d00ffeell, KEY_MENU },
266 		{ 0x000000000500ffeell, KEY_PREVIOUS },
267 		{ 0x000000000700ffeell, KEY_REWIND },
268 		{ 0x000000000400ffeell, KEY_STOP },
269 		{ 0x000000003c00ffeell, KEY_PLAYPAUSE },
270 		{ 0x000000000800ffeell, KEY_FASTFORWARD },
271 		{ 0x000000000600ffeell, KEY_NEXT },
272 		{ 0x000000010000ffeell, KEY_RIGHT },
273 		{ 0x000001000000ffeell, KEY_LEFT },
274 		{ 0x000000003d00ffeell, KEY_SELECT },
275 		{ 0x000100000000ffeell, KEY_VOLUMEUP },
276 		{ 0x010000000000ffeell, KEY_VOLUMEDOWN },
277 		{ 0x000000000100ffeell, KEY_MUTE },
278 		/* 0xffdc iMON MCE VFD */
279 		{ 0x00010000ffffffeell, KEY_VOLUMEUP },
280 		{ 0x01000000ffffffeell, KEY_VOLUMEDOWN },
281 		{ 0x00000001ffffffeell, KEY_MUTE },
282 		{ 0x0000000fffffffeell, KEY_MEDIA },
283 		{ 0x00000012ffffffeell, KEY_UP },
284 		{ 0x00000013ffffffeell, KEY_DOWN },
285 		{ 0x00000014ffffffeell, KEY_LEFT },
286 		{ 0x00000015ffffffeell, KEY_RIGHT },
287 		{ 0x00000016ffffffeell, KEY_ENTER },
288 		{ 0x00000017ffffffeell, KEY_ESC },
289 		/* iMON Knob values */
290 		{ 0x000100ffffffffeell, KEY_VOLUMEUP },
291 		{ 0x010000ffffffffeell, KEY_VOLUMEDOWN },
292 		{ 0x000008ffffffffeell, KEY_MUTE },
293 		{ 0, KEY_RESERVED },
294 	}
295 };
296 
297 /* imon receiver front panel/knob key table for DH102*/
298 static const struct imon_usb_dev_descr imon_DH102 = {
299 	.flags = IMON_NO_FLAGS,
300 	.key_table = {
301 		{ 0x000100000000ffeell, KEY_VOLUMEUP },
302 		{ 0x010000000000ffeell, KEY_VOLUMEDOWN },
303 		{ 0x000000010000ffeell, KEY_MUTE },
304 		{ 0x0000000f0000ffeell, KEY_MEDIA },
305 		{ 0x000000120000ffeell, KEY_UP },
306 		{ 0x000000130000ffeell, KEY_DOWN },
307 		{ 0x000000140000ffeell, KEY_LEFT },
308 		{ 0x000000150000ffeell, KEY_RIGHT },
309 		{ 0x000000160000ffeell, KEY_ENTER },
310 		{ 0x000000170000ffeell, KEY_ESC },
311 		{ 0x0000002b0000ffeell, KEY_EXIT },
312 		{ 0x0000002c0000ffeell, KEY_SELECT },
313 		{ 0x0000002d0000ffeell, KEY_MENU },
314 		{ 0, KEY_RESERVED }
315 	}
316 };
317 
318 /*
319  * USB Device ID for iMON USB Control Boards
320  *
321  * The Windows drivers contain 6 different inf files, more or less one for
322  * each new device until the 0x0034-0x0046 devices, which all use the same
323  * driver. Some of the devices in the 34-46 range haven't been definitively
324  * identified yet. Early devices have either a TriGem Computer, Inc. or a
325  * Samsung vendor ID (0x0aa8 and 0x04e8 respectively), while all later
326  * devices use the SoundGraph vendor ID (0x15c2). This driver only supports
327  * the ffdc and later devices, which do onboard decoding.
328  */
329 static const struct usb_device_id imon_usb_id_table[] = {
330 	/*
331 	 * Several devices with this same device ID, all use iMON_PAD.inf
332 	 * SoundGraph iMON PAD (IR & VFD)
333 	 * SoundGraph iMON PAD (IR & LCD)
334 	 * SoundGraph iMON Knob (IR only)
335 	 */
336 	{ USB_DEVICE(0x15c2, 0xffdc),
337 	  .driver_info = (unsigned long)&imon_default_table },
338 
339 	/*
340 	 * Newer devices, all driven by the latest iMON Windows driver, full
341 	 * list of device IDs extracted via 'strings Setup/data1.hdr |grep 15c2'
342 	 * Need user input to fill in details on unknown devices.
343 	 */
344 	/* SoundGraph iMON OEM Touch LCD (IR & 7" VGA LCD) */
345 	{ USB_DEVICE(0x15c2, 0x0034),
346 	  .driver_info = (unsigned long)&imon_DH102 },
347 	/* SoundGraph iMON OEM Touch LCD (IR & 4.3" VGA LCD) */
348 	{ USB_DEVICE(0x15c2, 0x0035),
349 	  .driver_info = (unsigned long)&imon_default_table},
350 	/* SoundGraph iMON OEM VFD (IR & VFD) */
351 	{ USB_DEVICE(0x15c2, 0x0036),
352 	  .driver_info = (unsigned long)&imon_OEM_VFD },
353 	/* device specifics unknown */
354 	{ USB_DEVICE(0x15c2, 0x0037),
355 	  .driver_info = (unsigned long)&imon_default_table},
356 	/* SoundGraph iMON OEM LCD (IR & LCD) */
357 	{ USB_DEVICE(0x15c2, 0x0038),
358 	  .driver_info = (unsigned long)&imon_default_table},
359 	/* SoundGraph iMON UltraBay (IR & LCD) */
360 	{ USB_DEVICE(0x15c2, 0x0039),
361 	  .driver_info = (unsigned long)&imon_default_table},
362 	/* device specifics unknown */
363 	{ USB_DEVICE(0x15c2, 0x003a),
364 	  .driver_info = (unsigned long)&imon_default_table},
365 	/* device specifics unknown */
366 	{ USB_DEVICE(0x15c2, 0x003b),
367 	  .driver_info = (unsigned long)&imon_default_table},
368 	/* SoundGraph iMON OEM Inside (IR only) */
369 	{ USB_DEVICE(0x15c2, 0x003c),
370 	  .driver_info = (unsigned long)&imon_default_table},
371 	/* device specifics unknown */
372 	{ USB_DEVICE(0x15c2, 0x003d),
373 	  .driver_info = (unsigned long)&imon_default_table},
374 	/* device specifics unknown */
375 	{ USB_DEVICE(0x15c2, 0x003e),
376 	  .driver_info = (unsigned long)&imon_default_table},
377 	/* device specifics unknown */
378 	{ USB_DEVICE(0x15c2, 0x003f),
379 	  .driver_info = (unsigned long)&imon_default_table},
380 	/* device specifics unknown */
381 	{ USB_DEVICE(0x15c2, 0x0040),
382 	  .driver_info = (unsigned long)&imon_default_table},
383 	/* SoundGraph iMON MINI (IR only) */
384 	{ USB_DEVICE(0x15c2, 0x0041),
385 	  .driver_info = (unsigned long)&imon_default_table},
386 	/* Antec Veris Multimedia Station EZ External (IR only) */
387 	{ USB_DEVICE(0x15c2, 0x0042),
388 	  .driver_info = (unsigned long)&imon_default_table},
389 	/* Antec Veris Multimedia Station Basic Internal (IR only) */
390 	{ USB_DEVICE(0x15c2, 0x0043),
391 	  .driver_info = (unsigned long)&imon_default_table},
392 	/* Antec Veris Multimedia Station Elite (IR & VFD) */
393 	{ USB_DEVICE(0x15c2, 0x0044),
394 	  .driver_info = (unsigned long)&imon_default_table},
395 	/* Antec Veris Multimedia Station Premiere (IR & LCD) */
396 	{ USB_DEVICE(0x15c2, 0x0045),
397 	  .driver_info = (unsigned long)&imon_default_table},
398 	/* device specifics unknown */
399 	{ USB_DEVICE(0x15c2, 0x0046),
400 	  .driver_info = (unsigned long)&imon_default_table},
401 	{}
402 };
403 
404 /* USB Device data */
405 static struct usb_driver imon_driver = {
406 	.name		= MOD_NAME,
407 	.probe		= imon_probe,
408 	.disconnect	= imon_disconnect,
409 	.suspend	= imon_suspend,
410 	.resume		= imon_resume,
411 	.id_table	= imon_usb_id_table,
412 };
413 
414 /* to prevent races between open() and disconnect(), probing, etc */
415 static DEFINE_MUTEX(driver_lock);
416 
417 /* Module bookkeeping bits */
418 MODULE_AUTHOR(MOD_AUTHOR);
419 MODULE_DESCRIPTION(MOD_DESC);
420 MODULE_VERSION(MOD_VERSION);
421 MODULE_LICENSE("GPL");
422 MODULE_DEVICE_TABLE(usb, imon_usb_id_table);
423 
424 static bool debug;
425 module_param(debug, bool, S_IRUGO | S_IWUSR);
426 MODULE_PARM_DESC(debug, "Debug messages: 0=no, 1=yes (default: no)");
427 
428 /* lcd, vfd, vga or none? should be auto-detected, but can be overridden... */
429 static int display_type;
430 module_param(display_type, int, S_IRUGO);
431 MODULE_PARM_DESC(display_type, "Type of attached display. 0=autodetect, 1=vfd, 2=lcd, 3=vga, 4=none (default: autodetect)");
432 
433 static int pad_stabilize = 1;
434 module_param(pad_stabilize, int, S_IRUGO | S_IWUSR);
435 MODULE_PARM_DESC(pad_stabilize, "Apply stabilization algorithm to iMON PAD presses in arrow key mode. 0=disable, 1=enable (default).");
436 
437 /*
438  * In certain use cases, mouse mode isn't really helpful, and could actually
439  * cause confusion, so allow disabling it when the IR device is open.
440  */
441 static bool nomouse;
442 module_param(nomouse, bool, S_IRUGO | S_IWUSR);
443 MODULE_PARM_DESC(nomouse, "Disable mouse input device mode when IR device is open. 0=don't disable, 1=disable. (default: don't disable)");
444 
445 /* threshold at which a pad push registers as an arrow key in kbd mode */
446 static int pad_thresh;
447 module_param(pad_thresh, int, S_IRUGO | S_IWUSR);
448 MODULE_PARM_DESC(pad_thresh, "Threshold at which a pad push registers as an arrow key in kbd mode (default: 28)");
449 
450 
451 static void free_imon_context(struct imon_context *ictx)
452 {
453 	struct device *dev = ictx->dev;
454 
455 	usb_free_urb(ictx->tx_urb);
456 	usb_free_urb(ictx->rx_urb_intf0);
457 	usb_free_urb(ictx->rx_urb_intf1);
458 	kfree(ictx);
459 
460 	dev_dbg(dev, "%s: iMON context freed\n", __func__);
461 }
462 
463 /*
464  * Called when the Display device (e.g. /dev/lcd0)
465  * is opened by the application.
466  */
467 static int display_open(struct inode *inode, struct file *file)
468 {
469 	struct usb_interface *interface;
470 	struct imon_context *ictx = NULL;
471 	int subminor;
472 	int retval = 0;
473 
474 	/* prevent races with disconnect */
475 	mutex_lock(&driver_lock);
476 
477 	subminor = iminor(inode);
478 	interface = usb_find_interface(&imon_driver, subminor);
479 	if (!interface) {
480 		pr_err("could not find interface for minor %d\n", subminor);
481 		retval = -ENODEV;
482 		goto exit;
483 	}
484 	ictx = usb_get_intfdata(interface);
485 
486 	if (!ictx) {
487 		pr_err("no context found for minor %d\n", subminor);
488 		retval = -ENODEV;
489 		goto exit;
490 	}
491 
492 	mutex_lock(&ictx->lock);
493 
494 	if (!ictx->display_supported) {
495 		pr_err("display not supported by device\n");
496 		retval = -ENODEV;
497 	} else if (ictx->display_isopen) {
498 		pr_err("display port is already open\n");
499 		retval = -EBUSY;
500 	} else {
501 		ictx->display_isopen = true;
502 		file->private_data = ictx;
503 		dev_dbg(ictx->dev, "display port opened\n");
504 	}
505 
506 	mutex_unlock(&ictx->lock);
507 
508 exit:
509 	mutex_unlock(&driver_lock);
510 	return retval;
511 }
512 
513 /*
514  * Called when the display device (e.g. /dev/lcd0)
515  * is closed by the application.
516  */
517 static int display_close(struct inode *inode, struct file *file)
518 {
519 	struct imon_context *ictx = NULL;
520 	int retval = 0;
521 
522 	ictx = file->private_data;
523 
524 	if (!ictx) {
525 		pr_err("no context for device\n");
526 		return -ENODEV;
527 	}
528 
529 	mutex_lock(&ictx->lock);
530 
531 	if (!ictx->display_supported) {
532 		pr_err("display not supported by device\n");
533 		retval = -ENODEV;
534 	} else if (!ictx->display_isopen) {
535 		pr_err("display is not open\n");
536 		retval = -EIO;
537 	} else {
538 		ictx->display_isopen = false;
539 		dev_dbg(ictx->dev, "display port closed\n");
540 	}
541 
542 	mutex_unlock(&ictx->lock);
543 	return retval;
544 }
545 
546 /*
547  * Sends a packet to the device -- this function must be called with
548  * ictx->lock held, or its unlock/lock sequence while waiting for tx
549  * to complete can/will lead to a deadlock.
550  */
551 static int send_packet(struct imon_context *ictx)
552 {
553 	unsigned int pipe;
554 	unsigned long timeout;
555 	int interval = 0;
556 	int retval = 0;
557 	struct usb_ctrlrequest *control_req = NULL;
558 
559 	/* Check if we need to use control or interrupt urb */
560 	if (!ictx->tx_control) {
561 		pipe = usb_sndintpipe(ictx->usbdev_intf0,
562 				      ictx->tx_endpoint->bEndpointAddress);
563 		interval = ictx->tx_endpoint->bInterval;
564 
565 		usb_fill_int_urb(ictx->tx_urb, ictx->usbdev_intf0, pipe,
566 				 ictx->usb_tx_buf,
567 				 sizeof(ictx->usb_tx_buf),
568 				 usb_tx_callback, ictx, interval);
569 
570 		ictx->tx_urb->actual_length = 0;
571 	} else {
572 		/* fill request into kmalloc'ed space: */
573 		control_req = kmalloc(sizeof(*control_req), GFP_KERNEL);
574 		if (control_req == NULL)
575 			return -ENOMEM;
576 
577 		/* setup packet is '21 09 0200 0001 0008' */
578 		control_req->bRequestType = 0x21;
579 		control_req->bRequest = 0x09;
580 		control_req->wValue = cpu_to_le16(0x0200);
581 		control_req->wIndex = cpu_to_le16(0x0001);
582 		control_req->wLength = cpu_to_le16(0x0008);
583 
584 		/* control pipe is endpoint 0x00 */
585 		pipe = usb_sndctrlpipe(ictx->usbdev_intf0, 0);
586 
587 		/* build the control urb */
588 		usb_fill_control_urb(ictx->tx_urb, ictx->usbdev_intf0,
589 				     pipe, (unsigned char *)control_req,
590 				     ictx->usb_tx_buf,
591 				     sizeof(ictx->usb_tx_buf),
592 				     usb_tx_callback, ictx);
593 		ictx->tx_urb->actual_length = 0;
594 	}
595 
596 	reinit_completion(&ictx->tx.finished);
597 	ictx->tx.busy = true;
598 	smp_rmb(); /* ensure later readers know we're busy */
599 
600 	retval = usb_submit_urb(ictx->tx_urb, GFP_KERNEL);
601 	if (retval) {
602 		ictx->tx.busy = false;
603 		smp_rmb(); /* ensure later readers know we're not busy */
604 		pr_err_ratelimited("error submitting urb(%d)\n", retval);
605 	} else {
606 		/* Wait for transmission to complete (or abort) */
607 		mutex_unlock(&ictx->lock);
608 		retval = wait_for_completion_interruptible(
609 				&ictx->tx.finished);
610 		if (retval) {
611 			usb_kill_urb(ictx->tx_urb);
612 			pr_err_ratelimited("task interrupted\n");
613 		}
614 		mutex_lock(&ictx->lock);
615 
616 		retval = ictx->tx.status;
617 		if (retval)
618 			pr_err_ratelimited("packet tx failed (%d)\n", retval);
619 	}
620 
621 	kfree(control_req);
622 
623 	/*
624 	 * Induce a mandatory delay before returning, as otherwise,
625 	 * send_packet can get called so rapidly as to overwhelm the device,
626 	 * particularly on faster systems and/or those with quirky usb.
627 	 */
628 	timeout = msecs_to_jiffies(ictx->send_packet_delay);
629 	set_current_state(TASK_INTERRUPTIBLE);
630 	schedule_timeout(timeout);
631 
632 	return retval;
633 }
634 
635 /*
636  * Sends an associate packet to the iMON 2.4G.
637  *
638  * This might not be such a good idea, since it has an id collision with
639  * some versions of the "IR & VFD" combo. The only way to determine if it
640  * is an RF version is to look at the product description string. (Which
641  * we currently do not fetch).
642  */
643 static int send_associate_24g(struct imon_context *ictx)
644 {
645 	int retval;
646 	const unsigned char packet[8] = { 0x01, 0x00, 0x00, 0x00,
647 					  0x00, 0x00, 0x00, 0x20 };
648 
649 	if (!ictx) {
650 		pr_err("no context for device\n");
651 		return -ENODEV;
652 	}
653 
654 	if (!ictx->dev_present_intf0) {
655 		pr_err("no iMON device present\n");
656 		return -ENODEV;
657 	}
658 
659 	memcpy(ictx->usb_tx_buf, packet, sizeof(packet));
660 	retval = send_packet(ictx);
661 
662 	return retval;
663 }
664 
665 /*
666  * Sends packets to setup and show clock on iMON display
667  *
668  * Arguments: year - last 2 digits of year, month - 1..12,
669  * day - 1..31, dow - day of the week (0-Sun...6-Sat),
670  * hour - 0..23, minute - 0..59, second - 0..59
671  */
672 static int send_set_imon_clock(struct imon_context *ictx,
673 			       unsigned int year, unsigned int month,
674 			       unsigned int day, unsigned int dow,
675 			       unsigned int hour, unsigned int minute,
676 			       unsigned int second)
677 {
678 	unsigned char clock_enable_pkt[IMON_CLOCK_ENABLE_PACKETS][8];
679 	int retval = 0;
680 	int i;
681 
682 	if (!ictx) {
683 		pr_err("no context for device\n");
684 		return -ENODEV;
685 	}
686 
687 	switch (ictx->display_type) {
688 	case IMON_DISPLAY_TYPE_LCD:
689 		clock_enable_pkt[0][0] = 0x80;
690 		clock_enable_pkt[0][1] = year;
691 		clock_enable_pkt[0][2] = month-1;
692 		clock_enable_pkt[0][3] = day;
693 		clock_enable_pkt[0][4] = hour;
694 		clock_enable_pkt[0][5] = minute;
695 		clock_enable_pkt[0][6] = second;
696 
697 		clock_enable_pkt[1][0] = 0x80;
698 		clock_enable_pkt[1][1] = 0;
699 		clock_enable_pkt[1][2] = 0;
700 		clock_enable_pkt[1][3] = 0;
701 		clock_enable_pkt[1][4] = 0;
702 		clock_enable_pkt[1][5] = 0;
703 		clock_enable_pkt[1][6] = 0;
704 
705 		if (ictx->product == 0xffdc) {
706 			clock_enable_pkt[0][7] = 0x50;
707 			clock_enable_pkt[1][7] = 0x51;
708 		} else {
709 			clock_enable_pkt[0][7] = 0x88;
710 			clock_enable_pkt[1][7] = 0x8a;
711 		}
712 
713 		break;
714 
715 	case IMON_DISPLAY_TYPE_VFD:
716 		clock_enable_pkt[0][0] = year;
717 		clock_enable_pkt[0][1] = month-1;
718 		clock_enable_pkt[0][2] = day;
719 		clock_enable_pkt[0][3] = dow;
720 		clock_enable_pkt[0][4] = hour;
721 		clock_enable_pkt[0][5] = minute;
722 		clock_enable_pkt[0][6] = second;
723 		clock_enable_pkt[0][7] = 0x40;
724 
725 		clock_enable_pkt[1][0] = 0;
726 		clock_enable_pkt[1][1] = 0;
727 		clock_enable_pkt[1][2] = 1;
728 		clock_enable_pkt[1][3] = 0;
729 		clock_enable_pkt[1][4] = 0;
730 		clock_enable_pkt[1][5] = 0;
731 		clock_enable_pkt[1][6] = 0;
732 		clock_enable_pkt[1][7] = 0x42;
733 
734 		break;
735 
736 	default:
737 		return -ENODEV;
738 	}
739 
740 	for (i = 0; i < IMON_CLOCK_ENABLE_PACKETS; i++) {
741 		memcpy(ictx->usb_tx_buf, clock_enable_pkt[i], 8);
742 		retval = send_packet(ictx);
743 		if (retval) {
744 			pr_err("send_packet failed for packet %d\n", i);
745 			break;
746 		}
747 	}
748 
749 	return retval;
750 }
751 
752 /*
753  * These are the sysfs functions to handle the association on the iMON 2.4G LT.
754  */
755 static ssize_t show_associate_remote(struct device *d,
756 				     struct device_attribute *attr,
757 				     char *buf)
758 {
759 	struct imon_context *ictx = dev_get_drvdata(d);
760 
761 	if (!ictx)
762 		return -ENODEV;
763 
764 	mutex_lock(&ictx->lock);
765 	if (ictx->rf_isassociating)
766 		strscpy(buf, "associating\n", PAGE_SIZE);
767 	else
768 		strscpy(buf, "closed\n", PAGE_SIZE);
769 
770 	dev_info(d, "Visit http://www.lirc.org/html/imon-24g.html for instructions on how to associate your iMON 2.4G DT/LT remote\n");
771 	mutex_unlock(&ictx->lock);
772 	return strlen(buf);
773 }
774 
775 static ssize_t store_associate_remote(struct device *d,
776 				      struct device_attribute *attr,
777 				      const char *buf, size_t count)
778 {
779 	struct imon_context *ictx;
780 
781 	ictx = dev_get_drvdata(d);
782 
783 	if (!ictx)
784 		return -ENODEV;
785 
786 	mutex_lock(&ictx->lock);
787 	ictx->rf_isassociating = true;
788 	send_associate_24g(ictx);
789 	mutex_unlock(&ictx->lock);
790 
791 	return count;
792 }
793 
794 /*
795  * sysfs functions to control internal imon clock
796  */
797 static ssize_t show_imon_clock(struct device *d,
798 			       struct device_attribute *attr, char *buf)
799 {
800 	struct imon_context *ictx = dev_get_drvdata(d);
801 	size_t len;
802 
803 	if (!ictx)
804 		return -ENODEV;
805 
806 	mutex_lock(&ictx->lock);
807 
808 	if (!ictx->display_supported) {
809 		len = snprintf(buf, PAGE_SIZE, "Not supported.");
810 	} else {
811 		len = snprintf(buf, PAGE_SIZE,
812 			"To set the clock on your iMON display:\n"
813 			"# date \"+%%y %%m %%d %%w %%H %%M %%S\" > imon_clock\n"
814 			"%s", ictx->display_isopen ?
815 			"\nNOTE: imon device must be closed\n" : "");
816 	}
817 
818 	mutex_unlock(&ictx->lock);
819 
820 	return len;
821 }
822 
823 static ssize_t store_imon_clock(struct device *d,
824 				struct device_attribute *attr,
825 				const char *buf, size_t count)
826 {
827 	struct imon_context *ictx = dev_get_drvdata(d);
828 	ssize_t retval;
829 	unsigned int year, month, day, dow, hour, minute, second;
830 
831 	if (!ictx)
832 		return -ENODEV;
833 
834 	mutex_lock(&ictx->lock);
835 
836 	if (!ictx->display_supported) {
837 		retval = -ENODEV;
838 		goto exit;
839 	} else if (ictx->display_isopen) {
840 		retval = -EBUSY;
841 		goto exit;
842 	}
843 
844 	if (sscanf(buf, "%u %u %u %u %u %u %u",	&year, &month, &day, &dow,
845 		   &hour, &minute, &second) != 7) {
846 		retval = -EINVAL;
847 		goto exit;
848 	}
849 
850 	if ((month < 1 || month > 12) ||
851 	    (day < 1 || day > 31) || (dow > 6) ||
852 	    (hour > 23) || (minute > 59) || (second > 59)) {
853 		retval = -EINVAL;
854 		goto exit;
855 	}
856 
857 	retval = send_set_imon_clock(ictx, year, month, day, dow,
858 				     hour, minute, second);
859 	if (retval)
860 		goto exit;
861 
862 	retval = count;
863 exit:
864 	mutex_unlock(&ictx->lock);
865 
866 	return retval;
867 }
868 
869 
870 static DEVICE_ATTR(imon_clock, S_IWUSR | S_IRUGO, show_imon_clock,
871 		   store_imon_clock);
872 
873 static DEVICE_ATTR(associate_remote, S_IWUSR | S_IRUGO, show_associate_remote,
874 		   store_associate_remote);
875 
876 static struct attribute *imon_display_sysfs_entries[] = {
877 	&dev_attr_imon_clock.attr,
878 	NULL
879 };
880 
881 static const struct attribute_group imon_display_attr_group = {
882 	.attrs = imon_display_sysfs_entries
883 };
884 
885 static struct attribute *imon_rf_sysfs_entries[] = {
886 	&dev_attr_associate_remote.attr,
887 	NULL
888 };
889 
890 static const struct attribute_group imon_rf_attr_group = {
891 	.attrs = imon_rf_sysfs_entries
892 };
893 
894 /*
895  * Writes data to the VFD.  The iMON VFD is 2x16 characters
896  * and requires data in 5 consecutive USB interrupt packets,
897  * each packet but the last carrying 7 bytes.
898  *
899  * I don't know if the VFD board supports features such as
900  * scrolling, clearing rows, blanking, etc. so at
901  * the caller must provide a full screen of data.  If fewer
902  * than 32 bytes are provided spaces will be appended to
903  * generate a full screen.
904  */
905 static ssize_t vfd_write(struct file *file, const char __user *buf,
906 			 size_t n_bytes, loff_t *pos)
907 {
908 	int i;
909 	int offset;
910 	int seq;
911 	int retval = 0;
912 	struct imon_context *ictx;
913 	static const unsigned char vfd_packet6[] = {
914 		0x01, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF };
915 
916 	ictx = file->private_data;
917 	if (!ictx) {
918 		pr_err_ratelimited("no context for device\n");
919 		return -ENODEV;
920 	}
921 
922 	mutex_lock(&ictx->lock);
923 
924 	if (!ictx->dev_present_intf0) {
925 		pr_err_ratelimited("no iMON device present\n");
926 		retval = -ENODEV;
927 		goto exit;
928 	}
929 
930 	if (n_bytes <= 0 || n_bytes > 32) {
931 		pr_err_ratelimited("invalid payload size\n");
932 		retval = -EINVAL;
933 		goto exit;
934 	}
935 
936 	if (copy_from_user(ictx->tx.data_buf, buf, n_bytes)) {
937 		retval = -EFAULT;
938 		goto exit;
939 	}
940 
941 	/* Pad with spaces */
942 	for (i = n_bytes; i < 32; ++i)
943 		ictx->tx.data_buf[i] = ' ';
944 
945 	for (i = 32; i < 35; ++i)
946 		ictx->tx.data_buf[i] = 0xFF;
947 
948 	offset = 0;
949 	seq = 0;
950 
951 	do {
952 		memcpy(ictx->usb_tx_buf, ictx->tx.data_buf + offset, 7);
953 		ictx->usb_tx_buf[7] = (unsigned char) seq;
954 
955 		retval = send_packet(ictx);
956 		if (retval) {
957 			pr_err_ratelimited("send packet #%d failed\n", seq / 2);
958 			goto exit;
959 		} else {
960 			seq += 2;
961 			offset += 7;
962 		}
963 
964 	} while (offset < 35);
965 
966 	/* Send packet #6 */
967 	memcpy(ictx->usb_tx_buf, &vfd_packet6, sizeof(vfd_packet6));
968 	ictx->usb_tx_buf[7] = (unsigned char) seq;
969 	retval = send_packet(ictx);
970 	if (retval)
971 		pr_err_ratelimited("send packet #%d failed\n", seq / 2);
972 
973 exit:
974 	mutex_unlock(&ictx->lock);
975 
976 	return (!retval) ? n_bytes : retval;
977 }
978 
979 /*
980  * Writes data to the LCD.  The iMON OEM LCD screen expects 8-byte
981  * packets. We accept data as 16 hexadecimal digits, followed by a
982  * newline (to make it easy to drive the device from a command-line
983  * -- even though the actual binary data is a bit complicated).
984  *
985  * The device itself is not a "traditional" text-mode display. It's
986  * actually a 16x96 pixel bitmap display. That means if you want to
987  * display text, you've got to have your own "font" and translate the
988  * text into bitmaps for display. This is really flexible (you can
989  * display whatever diacritics you need, and so on), but it's also
990  * a lot more complicated than most LCDs...
991  */
992 static ssize_t lcd_write(struct file *file, const char __user *buf,
993 			 size_t n_bytes, loff_t *pos)
994 {
995 	int retval = 0;
996 	struct imon_context *ictx;
997 
998 	ictx = file->private_data;
999 	if (!ictx) {
1000 		pr_err_ratelimited("no context for device\n");
1001 		return -ENODEV;
1002 	}
1003 
1004 	mutex_lock(&ictx->lock);
1005 
1006 	if (!ictx->display_supported) {
1007 		pr_err_ratelimited("no iMON display present\n");
1008 		retval = -ENODEV;
1009 		goto exit;
1010 	}
1011 
1012 	if (n_bytes != 8) {
1013 		pr_err_ratelimited("invalid payload size: %d (expected 8)\n",
1014 				   (int)n_bytes);
1015 		retval = -EINVAL;
1016 		goto exit;
1017 	}
1018 
1019 	if (copy_from_user(ictx->usb_tx_buf, buf, 8)) {
1020 		retval = -EFAULT;
1021 		goto exit;
1022 	}
1023 
1024 	retval = send_packet(ictx);
1025 	if (retval) {
1026 		pr_err_ratelimited("send packet failed!\n");
1027 		goto exit;
1028 	} else {
1029 		dev_dbg(ictx->dev, "%s: write %d bytes to LCD\n",
1030 			__func__, (int) n_bytes);
1031 	}
1032 exit:
1033 	mutex_unlock(&ictx->lock);
1034 	return (!retval) ? n_bytes : retval;
1035 }
1036 
1037 /*
1038  * Callback function for USB core API: transmit data
1039  */
1040 static void usb_tx_callback(struct urb *urb)
1041 {
1042 	struct imon_context *ictx;
1043 
1044 	if (!urb)
1045 		return;
1046 	ictx = (struct imon_context *)urb->context;
1047 	if (!ictx)
1048 		return;
1049 
1050 	ictx->tx.status = urb->status;
1051 
1052 	/* notify waiters that write has finished */
1053 	ictx->tx.busy = false;
1054 	smp_rmb(); /* ensure later readers know we're not busy */
1055 	complete(&ictx->tx.finished);
1056 }
1057 
1058 /*
1059  * report touchscreen input
1060  */
1061 static void imon_touch_display_timeout(struct timer_list *t)
1062 {
1063 	struct imon_context *ictx = from_timer(ictx, t, ttimer);
1064 
1065 	if (ictx->display_type != IMON_DISPLAY_TYPE_VGA)
1066 		return;
1067 
1068 	input_report_abs(ictx->touch, ABS_X, ictx->touch_x);
1069 	input_report_abs(ictx->touch, ABS_Y, ictx->touch_y);
1070 	input_report_key(ictx->touch, BTN_TOUCH, 0x00);
1071 	input_sync(ictx->touch);
1072 }
1073 
1074 /*
1075  * iMON IR receivers support two different signal sets -- those used by
1076  * the iMON remotes, and those used by the Windows MCE remotes (which is
1077  * really just RC-6), but only one or the other at a time, as the signals
1078  * are decoded onboard the receiver.
1079  *
1080  * This function gets called two different ways, one way is from
1081  * rc_register_device, for initial protocol selection/setup, and the other is
1082  * via a userspace-initiated protocol change request, either by direct sysfs
1083  * prodding or by something like ir-keytable. In the rc_register_device case,
1084  * the imon context lock is already held, but when initiated from userspace,
1085  * it is not, so we must acquire it prior to calling send_packet, which
1086  * requires that the lock is held.
1087  */
1088 static int imon_ir_change_protocol(struct rc_dev *rc, u64 *rc_proto)
1089 {
1090 	int retval;
1091 	struct imon_context *ictx = rc->priv;
1092 	struct device *dev = ictx->dev;
1093 	bool unlock = false;
1094 	unsigned char ir_proto_packet[] = {
1095 		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x86 };
1096 
1097 	if (*rc_proto && !(*rc_proto & rc->allowed_protocols))
1098 		dev_warn(dev, "Looks like you're trying to use an IR protocol this device does not support\n");
1099 
1100 	if (*rc_proto & RC_PROTO_BIT_RC6_MCE) {
1101 		dev_dbg(dev, "Configuring IR receiver for MCE protocol\n");
1102 		ir_proto_packet[0] = 0x01;
1103 		*rc_proto = RC_PROTO_BIT_RC6_MCE;
1104 	} else if (*rc_proto & RC_PROTO_BIT_IMON) {
1105 		dev_dbg(dev, "Configuring IR receiver for iMON protocol\n");
1106 		if (!pad_stabilize)
1107 			dev_dbg(dev, "PAD stabilize functionality disabled\n");
1108 		/* ir_proto_packet[0] = 0x00; // already the default */
1109 		*rc_proto = RC_PROTO_BIT_IMON;
1110 	} else {
1111 		dev_warn(dev, "Unsupported IR protocol specified, overriding to iMON IR protocol\n");
1112 		if (!pad_stabilize)
1113 			dev_dbg(dev, "PAD stabilize functionality disabled\n");
1114 		/* ir_proto_packet[0] = 0x00; // already the default */
1115 		*rc_proto = RC_PROTO_BIT_IMON;
1116 	}
1117 
1118 	memcpy(ictx->usb_tx_buf, &ir_proto_packet, sizeof(ir_proto_packet));
1119 
1120 	if (!mutex_is_locked(&ictx->lock)) {
1121 		unlock = true;
1122 		mutex_lock(&ictx->lock);
1123 	}
1124 
1125 	retval = send_packet(ictx);
1126 	if (retval)
1127 		goto out;
1128 
1129 	ictx->rc_proto = *rc_proto;
1130 	ictx->pad_mouse = false;
1131 
1132 out:
1133 	if (unlock)
1134 		mutex_unlock(&ictx->lock);
1135 
1136 	return retval;
1137 }
1138 
1139 /*
1140  * The directional pad behaves a bit differently, depending on whether this is
1141  * one of the older ffdc devices or a newer device. Newer devices appear to
1142  * have a higher resolution matrix for more precise mouse movement, but it
1143  * makes things overly sensitive in keyboard mode, so we do some interesting
1144  * contortions to make it less touchy. Older devices run through the same
1145  * routine with shorter timeout and a smaller threshold.
1146  */
1147 static int stabilize(int a, int b, u16 timeout, u16 threshold)
1148 {
1149 	ktime_t ct;
1150 	static ktime_t prev_time;
1151 	static ktime_t hit_time;
1152 	static int x, y, prev_result, hits;
1153 	int result = 0;
1154 	long msec, msec_hit;
1155 
1156 	ct = ktime_get();
1157 	msec = ktime_ms_delta(ct, prev_time);
1158 	msec_hit = ktime_ms_delta(ct, hit_time);
1159 
1160 	if (msec > 100) {
1161 		x = 0;
1162 		y = 0;
1163 		hits = 0;
1164 	}
1165 
1166 	x += a;
1167 	y += b;
1168 
1169 	prev_time = ct;
1170 
1171 	if (abs(x) > threshold || abs(y) > threshold) {
1172 		if (abs(y) > abs(x))
1173 			result = (y > 0) ? 0x7F : 0x80;
1174 		else
1175 			result = (x > 0) ? 0x7F00 : 0x8000;
1176 
1177 		x = 0;
1178 		y = 0;
1179 
1180 		if (result == prev_result) {
1181 			hits++;
1182 
1183 			if (hits > 3) {
1184 				switch (result) {
1185 				case 0x7F:
1186 					y = 17 * threshold / 30;
1187 					break;
1188 				case 0x80:
1189 					y -= 17 * threshold / 30;
1190 					break;
1191 				case 0x7F00:
1192 					x = 17 * threshold / 30;
1193 					break;
1194 				case 0x8000:
1195 					x -= 17 * threshold / 30;
1196 					break;
1197 				}
1198 			}
1199 
1200 			if (hits == 2 && msec_hit < timeout) {
1201 				result = 0;
1202 				hits = 1;
1203 			}
1204 		} else {
1205 			prev_result = result;
1206 			hits = 1;
1207 			hit_time = ct;
1208 		}
1209 	}
1210 
1211 	return result;
1212 }
1213 
1214 static u32 imon_remote_key_lookup(struct imon_context *ictx, u32 scancode)
1215 {
1216 	u32 keycode;
1217 	u32 release;
1218 	bool is_release_code = false;
1219 
1220 	/* Look for the initial press of a button */
1221 	keycode = rc_g_keycode_from_table(ictx->rdev, scancode);
1222 	ictx->rc_toggle = 0x0;
1223 	ictx->rc_scancode = scancode;
1224 
1225 	/* Look for the release of a button */
1226 	if (keycode == KEY_RESERVED) {
1227 		release = scancode & ~0x4000;
1228 		keycode = rc_g_keycode_from_table(ictx->rdev, release);
1229 		if (keycode != KEY_RESERVED)
1230 			is_release_code = true;
1231 	}
1232 
1233 	ictx->release_code = is_release_code;
1234 
1235 	return keycode;
1236 }
1237 
1238 static u32 imon_mce_key_lookup(struct imon_context *ictx, u32 scancode)
1239 {
1240 	u32 keycode;
1241 
1242 #define MCE_KEY_MASK 0x7000
1243 #define MCE_TOGGLE_BIT 0x8000
1244 
1245 	/*
1246 	 * On some receivers, mce keys decode to 0x8000f04xx and 0x8000f84xx
1247 	 * (the toggle bit flipping between alternating key presses), while
1248 	 * on other receivers, we see 0x8000f74xx and 0x8000ff4xx. To keep
1249 	 * the table trim, we always or in the bits to look up 0x8000ff4xx,
1250 	 * but we can't or them into all codes, as some keys are decoded in
1251 	 * a different way w/o the same use of the toggle bit...
1252 	 */
1253 	if (scancode & 0x80000000)
1254 		scancode = scancode | MCE_KEY_MASK | MCE_TOGGLE_BIT;
1255 
1256 	ictx->rc_scancode = scancode;
1257 	keycode = rc_g_keycode_from_table(ictx->rdev, scancode);
1258 
1259 	/* not used in mce mode, but make sure we know its false */
1260 	ictx->release_code = false;
1261 
1262 	return keycode;
1263 }
1264 
1265 static u32 imon_panel_key_lookup(struct imon_context *ictx, u64 code)
1266 {
1267 	int i;
1268 	u32 keycode = KEY_RESERVED;
1269 	struct imon_panel_key_table *key_table = ictx->dev_descr->key_table;
1270 
1271 	for (i = 0; key_table[i].hw_code != 0; i++) {
1272 		if (key_table[i].hw_code == (code | 0xffee)) {
1273 			keycode = key_table[i].keycode;
1274 			break;
1275 		}
1276 	}
1277 	ictx->release_code = false;
1278 	return keycode;
1279 }
1280 
1281 static bool imon_mouse_event(struct imon_context *ictx,
1282 			     unsigned char *buf, int len)
1283 {
1284 	signed char rel_x = 0x00, rel_y = 0x00;
1285 	u8 right_shift = 1;
1286 	bool mouse_input = true;
1287 	int dir = 0;
1288 	unsigned long flags;
1289 
1290 	spin_lock_irqsave(&ictx->kc_lock, flags);
1291 
1292 	/* newer iMON device PAD or mouse button */
1293 	if (ictx->product != 0xffdc && (buf[0] & 0x01) && len == 5) {
1294 		rel_x = buf[2];
1295 		rel_y = buf[3];
1296 		right_shift = 1;
1297 	/* 0xffdc iMON PAD or mouse button input */
1298 	} else if (ictx->product == 0xffdc && (buf[0] & 0x40) &&
1299 			!((buf[1] & 0x01) || ((buf[1] >> 2) & 0x01))) {
1300 		rel_x = (buf[1] & 0x08) | (buf[1] & 0x10) >> 2 |
1301 			(buf[1] & 0x20) >> 4 | (buf[1] & 0x40) >> 6;
1302 		if (buf[0] & 0x02)
1303 			rel_x |= ~0x0f;
1304 		rel_x = rel_x + rel_x / 2;
1305 		rel_y = (buf[2] & 0x08) | (buf[2] & 0x10) >> 2 |
1306 			(buf[2] & 0x20) >> 4 | (buf[2] & 0x40) >> 6;
1307 		if (buf[0] & 0x01)
1308 			rel_y |= ~0x0f;
1309 		rel_y = rel_y + rel_y / 2;
1310 		right_shift = 2;
1311 	/* some ffdc devices decode mouse buttons differently... */
1312 	} else if (ictx->product == 0xffdc && (buf[0] == 0x68)) {
1313 		right_shift = 2;
1314 	/* ch+/- buttons, which we use for an emulated scroll wheel */
1315 	} else if (ictx->kc == KEY_CHANNELUP && (buf[2] & 0x40) != 0x40) {
1316 		dir = 1;
1317 	} else if (ictx->kc == KEY_CHANNELDOWN && (buf[2] & 0x40) != 0x40) {
1318 		dir = -1;
1319 	} else
1320 		mouse_input = false;
1321 
1322 	spin_unlock_irqrestore(&ictx->kc_lock, flags);
1323 
1324 	if (mouse_input) {
1325 		dev_dbg(ictx->dev, "sending mouse data via input subsystem\n");
1326 
1327 		if (dir) {
1328 			input_report_rel(ictx->idev, REL_WHEEL, dir);
1329 		} else if (rel_x || rel_y) {
1330 			input_report_rel(ictx->idev, REL_X, rel_x);
1331 			input_report_rel(ictx->idev, REL_Y, rel_y);
1332 		} else {
1333 			input_report_key(ictx->idev, BTN_LEFT, buf[1] & 0x1);
1334 			input_report_key(ictx->idev, BTN_RIGHT,
1335 					 buf[1] >> right_shift & 0x1);
1336 		}
1337 		input_sync(ictx->idev);
1338 		spin_lock_irqsave(&ictx->kc_lock, flags);
1339 		ictx->last_keycode = ictx->kc;
1340 		spin_unlock_irqrestore(&ictx->kc_lock, flags);
1341 	}
1342 
1343 	return mouse_input;
1344 }
1345 
1346 static void imon_touch_event(struct imon_context *ictx, unsigned char *buf)
1347 {
1348 	mod_timer(&ictx->ttimer, jiffies + TOUCH_TIMEOUT);
1349 	ictx->touch_x = (buf[0] << 4) | (buf[1] >> 4);
1350 	ictx->touch_y = 0xfff - ((buf[2] << 4) | (buf[1] & 0xf));
1351 	input_report_abs(ictx->touch, ABS_X, ictx->touch_x);
1352 	input_report_abs(ictx->touch, ABS_Y, ictx->touch_y);
1353 	input_report_key(ictx->touch, BTN_TOUCH, 0x01);
1354 	input_sync(ictx->touch);
1355 }
1356 
1357 static void imon_pad_to_keys(struct imon_context *ictx, unsigned char *buf)
1358 {
1359 	int dir = 0;
1360 	signed char rel_x = 0x00, rel_y = 0x00;
1361 	u16 timeout, threshold;
1362 	u32 scancode = KEY_RESERVED;
1363 	unsigned long flags;
1364 
1365 	/*
1366 	 * The imon directional pad functions more like a touchpad. Bytes 3 & 4
1367 	 * contain a position coordinate (x,y), with each component ranging
1368 	 * from -14 to 14. We want to down-sample this to only 4 discrete values
1369 	 * for up/down/left/right arrow keys. Also, when you get too close to
1370 	 * diagonals, it has a tendency to jump back and forth, so lets try to
1371 	 * ignore when they get too close.
1372 	 */
1373 	if (ictx->product != 0xffdc) {
1374 		/* first, pad to 8 bytes so it conforms with everything else */
1375 		buf[5] = buf[6] = buf[7] = 0;
1376 		timeout = 500;	/* in msecs */
1377 		/* (2*threshold) x (2*threshold) square */
1378 		threshold = pad_thresh ? pad_thresh : 28;
1379 		rel_x = buf[2];
1380 		rel_y = buf[3];
1381 
1382 		if (ictx->rc_proto == RC_PROTO_BIT_IMON && pad_stabilize) {
1383 			if ((buf[1] == 0) && ((rel_x != 0) || (rel_y != 0))) {
1384 				dir = stabilize((int)rel_x, (int)rel_y,
1385 						timeout, threshold);
1386 				if (!dir) {
1387 					spin_lock_irqsave(&ictx->kc_lock,
1388 							  flags);
1389 					ictx->kc = KEY_UNKNOWN;
1390 					spin_unlock_irqrestore(&ictx->kc_lock,
1391 							       flags);
1392 					return;
1393 				}
1394 				buf[2] = dir & 0xFF;
1395 				buf[3] = (dir >> 8) & 0xFF;
1396 				scancode = be32_to_cpu(*((__be32 *)buf));
1397 			}
1398 		} else {
1399 			/*
1400 			 * Hack alert: instead of using keycodes, we have
1401 			 * to use hard-coded scancodes here...
1402 			 */
1403 			if (abs(rel_y) > abs(rel_x)) {
1404 				buf[2] = (rel_y > 0) ? 0x7F : 0x80;
1405 				buf[3] = 0;
1406 				if (rel_y > 0)
1407 					scancode = 0x01007f00; /* KEY_DOWN */
1408 				else
1409 					scancode = 0x01008000; /* KEY_UP */
1410 			} else {
1411 				buf[2] = 0;
1412 				buf[3] = (rel_x > 0) ? 0x7F : 0x80;
1413 				if (rel_x > 0)
1414 					scancode = 0x0100007f; /* KEY_RIGHT */
1415 				else
1416 					scancode = 0x01000080; /* KEY_LEFT */
1417 			}
1418 		}
1419 
1420 	/*
1421 	 * Handle on-board decoded pad events for e.g. older VFD/iMON-Pad
1422 	 * device (15c2:ffdc). The remote generates various codes from
1423 	 * 0x68nnnnB7 to 0x6AnnnnB7, the left mouse button generates
1424 	 * 0x688301b7 and the right one 0x688481b7. All other keys generate
1425 	 * 0x2nnnnnnn. Position coordinate is encoded in buf[1] and buf[2] with
1426 	 * reversed endianness. Extract direction from buffer, rotate endianness,
1427 	 * adjust sign and feed the values into stabilize(). The resulting codes
1428 	 * will be 0x01008000, 0x01007F00, which match the newer devices.
1429 	 */
1430 	} else {
1431 		timeout = 10;	/* in msecs */
1432 		/* (2*threshold) x (2*threshold) square */
1433 		threshold = pad_thresh ? pad_thresh : 15;
1434 
1435 		/* buf[1] is x */
1436 		rel_x = (buf[1] & 0x08) | (buf[1] & 0x10) >> 2 |
1437 			(buf[1] & 0x20) >> 4 | (buf[1] & 0x40) >> 6;
1438 		if (buf[0] & 0x02)
1439 			rel_x |= ~0x10+1;
1440 		/* buf[2] is y */
1441 		rel_y = (buf[2] & 0x08) | (buf[2] & 0x10) >> 2 |
1442 			(buf[2] & 0x20) >> 4 | (buf[2] & 0x40) >> 6;
1443 		if (buf[0] & 0x01)
1444 			rel_y |= ~0x10+1;
1445 
1446 		buf[0] = 0x01;
1447 		buf[1] = buf[4] = buf[5] = buf[6] = buf[7] = 0;
1448 
1449 		if (ictx->rc_proto == RC_PROTO_BIT_IMON && pad_stabilize) {
1450 			dir = stabilize((int)rel_x, (int)rel_y,
1451 					timeout, threshold);
1452 			if (!dir) {
1453 				spin_lock_irqsave(&ictx->kc_lock, flags);
1454 				ictx->kc = KEY_UNKNOWN;
1455 				spin_unlock_irqrestore(&ictx->kc_lock, flags);
1456 				return;
1457 			}
1458 			buf[2] = dir & 0xFF;
1459 			buf[3] = (dir >> 8) & 0xFF;
1460 			scancode = be32_to_cpu(*((__be32 *)buf));
1461 		} else {
1462 			/*
1463 			 * Hack alert: instead of using keycodes, we have
1464 			 * to use hard-coded scancodes here...
1465 			 */
1466 			if (abs(rel_y) > abs(rel_x)) {
1467 				buf[2] = (rel_y > 0) ? 0x7F : 0x80;
1468 				buf[3] = 0;
1469 				if (rel_y > 0)
1470 					scancode = 0x01007f00; /* KEY_DOWN */
1471 				else
1472 					scancode = 0x01008000; /* KEY_UP */
1473 			} else {
1474 				buf[2] = 0;
1475 				buf[3] = (rel_x > 0) ? 0x7F : 0x80;
1476 				if (rel_x > 0)
1477 					scancode = 0x0100007f; /* KEY_RIGHT */
1478 				else
1479 					scancode = 0x01000080; /* KEY_LEFT */
1480 			}
1481 		}
1482 	}
1483 
1484 	if (scancode) {
1485 		spin_lock_irqsave(&ictx->kc_lock, flags);
1486 		ictx->kc = imon_remote_key_lookup(ictx, scancode);
1487 		spin_unlock_irqrestore(&ictx->kc_lock, flags);
1488 	}
1489 }
1490 
1491 /*
1492  * figure out if these is a press or a release. We don't actually
1493  * care about repeats, as those will be auto-generated within the IR
1494  * subsystem for repeating scancodes.
1495  */
1496 static int imon_parse_press_type(struct imon_context *ictx,
1497 				 unsigned char *buf, u8 ktype)
1498 {
1499 	int press_type = 0;
1500 	unsigned long flags;
1501 
1502 	spin_lock_irqsave(&ictx->kc_lock, flags);
1503 
1504 	/* key release of 0x02XXXXXX key */
1505 	if (ictx->kc == KEY_RESERVED && buf[0] == 0x02 && buf[3] == 0x00)
1506 		ictx->kc = ictx->last_keycode;
1507 
1508 	/* mouse button release on (some) 0xffdc devices */
1509 	else if (ictx->kc == KEY_RESERVED && buf[0] == 0x68 && buf[1] == 0x82 &&
1510 		 buf[2] == 0x81 && buf[3] == 0xb7)
1511 		ictx->kc = ictx->last_keycode;
1512 
1513 	/* mouse button release on (some other) 0xffdc devices */
1514 	else if (ictx->kc == KEY_RESERVED && buf[0] == 0x01 && buf[1] == 0x00 &&
1515 		 buf[2] == 0x81 && buf[3] == 0xb7)
1516 		ictx->kc = ictx->last_keycode;
1517 
1518 	/* mce-specific button handling, no keyup events */
1519 	else if (ktype == IMON_KEY_MCE) {
1520 		ictx->rc_toggle = buf[2];
1521 		press_type = 1;
1522 
1523 	/* incoherent or irrelevant data */
1524 	} else if (ictx->kc == KEY_RESERVED)
1525 		press_type = -EINVAL;
1526 
1527 	/* key release of 0xXXXXXXb7 key */
1528 	else if (ictx->release_code)
1529 		press_type = 0;
1530 
1531 	/* this is a button press */
1532 	else
1533 		press_type = 1;
1534 
1535 	spin_unlock_irqrestore(&ictx->kc_lock, flags);
1536 
1537 	return press_type;
1538 }
1539 
1540 /*
1541  * Process the incoming packet
1542  */
1543 static void imon_incoming_packet(struct imon_context *ictx,
1544 				 struct urb *urb, int intf)
1545 {
1546 	int len = urb->actual_length;
1547 	unsigned char *buf = urb->transfer_buffer;
1548 	struct device *dev = ictx->dev;
1549 	unsigned long flags;
1550 	u32 kc;
1551 	u64 scancode;
1552 	int press_type = 0;
1553 	long msec;
1554 	ktime_t t;
1555 	static ktime_t prev_time;
1556 	u8 ktype;
1557 
1558 	/* filter out junk data on the older 0xffdc imon devices */
1559 	if ((buf[0] == 0xff) && (buf[1] == 0xff) && (buf[2] == 0xff))
1560 		return;
1561 
1562 	/* Figure out what key was pressed */
1563 	if (len == 8 && buf[7] == 0xee) {
1564 		scancode = be64_to_cpu(*((__be64 *)buf));
1565 		ktype = IMON_KEY_PANEL;
1566 		kc = imon_panel_key_lookup(ictx, scancode);
1567 		ictx->release_code = false;
1568 	} else {
1569 		scancode = be32_to_cpu(*((__be32 *)buf));
1570 		if (ictx->rc_proto == RC_PROTO_BIT_RC6_MCE) {
1571 			ktype = IMON_KEY_IMON;
1572 			if (buf[0] == 0x80)
1573 				ktype = IMON_KEY_MCE;
1574 			kc = imon_mce_key_lookup(ictx, scancode);
1575 		} else {
1576 			ktype = IMON_KEY_IMON;
1577 			kc = imon_remote_key_lookup(ictx, scancode);
1578 		}
1579 	}
1580 
1581 	spin_lock_irqsave(&ictx->kc_lock, flags);
1582 	/* keyboard/mouse mode toggle button */
1583 	if (kc == KEY_KEYBOARD && !ictx->release_code) {
1584 		ictx->last_keycode = kc;
1585 		if (!nomouse) {
1586 			ictx->pad_mouse = !ictx->pad_mouse;
1587 			dev_dbg(dev, "toggling to %s mode\n",
1588 				ictx->pad_mouse ? "mouse" : "keyboard");
1589 			spin_unlock_irqrestore(&ictx->kc_lock, flags);
1590 			return;
1591 		} else {
1592 			ictx->pad_mouse = false;
1593 			dev_dbg(dev, "mouse mode disabled, passing key value\n");
1594 		}
1595 	}
1596 
1597 	ictx->kc = kc;
1598 	spin_unlock_irqrestore(&ictx->kc_lock, flags);
1599 
1600 	/* send touchscreen events through input subsystem if touchpad data */
1601 	if (ictx->display_type == IMON_DISPLAY_TYPE_VGA && len == 8 &&
1602 	    buf[7] == 0x86) {
1603 		imon_touch_event(ictx, buf);
1604 		return;
1605 
1606 	/* look for mouse events with pad in mouse mode */
1607 	} else if (ictx->pad_mouse) {
1608 		if (imon_mouse_event(ictx, buf, len))
1609 			return;
1610 	}
1611 
1612 	/* Now for some special handling to convert pad input to arrow keys */
1613 	if (((len == 5) && (buf[0] == 0x01) && (buf[4] == 0x00)) ||
1614 	    ((len == 8) && (buf[0] & 0x40) &&
1615 	     !(buf[1] & 0x1 || buf[1] >> 2 & 0x1))) {
1616 		len = 8;
1617 		imon_pad_to_keys(ictx, buf);
1618 	}
1619 
1620 	if (debug) {
1621 		printk(KERN_INFO "intf%d decoded packet: %*ph\n",
1622 		       intf, len, buf);
1623 	}
1624 
1625 	press_type = imon_parse_press_type(ictx, buf, ktype);
1626 	if (press_type < 0)
1627 		goto not_input_data;
1628 
1629 	if (ktype != IMON_KEY_PANEL) {
1630 		if (press_type == 0)
1631 			rc_keyup(ictx->rdev);
1632 		else {
1633 			enum rc_proto proto;
1634 
1635 			if (ictx->rc_proto == RC_PROTO_BIT_RC6_MCE)
1636 				proto = RC_PROTO_RC6_MCE;
1637 			else if (ictx->rc_proto == RC_PROTO_BIT_IMON)
1638 				proto = RC_PROTO_IMON;
1639 			else
1640 				return;
1641 
1642 			rc_keydown(ictx->rdev, proto, ictx->rc_scancode,
1643 				   ictx->rc_toggle);
1644 
1645 			spin_lock_irqsave(&ictx->kc_lock, flags);
1646 			ictx->last_keycode = ictx->kc;
1647 			spin_unlock_irqrestore(&ictx->kc_lock, flags);
1648 		}
1649 		return;
1650 	}
1651 
1652 	/* Only panel type events left to process now */
1653 	spin_lock_irqsave(&ictx->kc_lock, flags);
1654 
1655 	t = ktime_get();
1656 	/* KEY_MUTE repeats from knob need to be suppressed */
1657 	if (ictx->kc == KEY_MUTE && ictx->kc == ictx->last_keycode) {
1658 		msec = ktime_ms_delta(t, prev_time);
1659 		if (msec < ictx->idev->rep[REP_DELAY]) {
1660 			spin_unlock_irqrestore(&ictx->kc_lock, flags);
1661 			return;
1662 		}
1663 	}
1664 	prev_time = t;
1665 	kc = ictx->kc;
1666 
1667 	spin_unlock_irqrestore(&ictx->kc_lock, flags);
1668 
1669 	input_report_key(ictx->idev, kc, press_type);
1670 	input_sync(ictx->idev);
1671 
1672 	/* panel keys don't generate a release */
1673 	input_report_key(ictx->idev, kc, 0);
1674 	input_sync(ictx->idev);
1675 
1676 	spin_lock_irqsave(&ictx->kc_lock, flags);
1677 	ictx->last_keycode = kc;
1678 	spin_unlock_irqrestore(&ictx->kc_lock, flags);
1679 
1680 	return;
1681 
1682 not_input_data:
1683 	if (len != 8) {
1684 		dev_warn(dev, "imon %s: invalid incoming packet size (len = %d, intf%d)\n",
1685 			 __func__, len, intf);
1686 		return;
1687 	}
1688 
1689 	/* iMON 2.4G associate frame */
1690 	if (buf[0] == 0x00 &&
1691 	    buf[2] == 0xFF &&				/* REFID */
1692 	    buf[3] == 0xFF &&
1693 	    buf[4] == 0xFF &&
1694 	    buf[5] == 0xFF &&				/* iMON 2.4G */
1695 	   ((buf[6] == 0x4E && buf[7] == 0xDF) ||	/* LT */
1696 	    (buf[6] == 0x5E && buf[7] == 0xDF))) {	/* DT */
1697 		dev_warn(dev, "%s: remote associated refid=%02X\n",
1698 			 __func__, buf[1]);
1699 		ictx->rf_isassociating = false;
1700 	}
1701 }
1702 
1703 /*
1704  * Callback function for USB core API: receive data
1705  */
1706 static void usb_rx_callback_intf0(struct urb *urb)
1707 {
1708 	struct imon_context *ictx;
1709 	int intfnum = 0;
1710 
1711 	if (!urb)
1712 		return;
1713 
1714 	ictx = (struct imon_context *)urb->context;
1715 	if (!ictx)
1716 		return;
1717 
1718 	/*
1719 	 * if we get a callback before we're done configuring the hardware, we
1720 	 * can't yet process the data, as there's nowhere to send it, but we
1721 	 * still need to submit a new rx URB to avoid wedging the hardware
1722 	 */
1723 	if (!ictx->dev_present_intf0)
1724 		goto out;
1725 
1726 	switch (urb->status) {
1727 	case -ENOENT:		/* usbcore unlink successful! */
1728 		return;
1729 
1730 	case -ESHUTDOWN:	/* transport endpoint was shut down */
1731 		break;
1732 
1733 	case 0:
1734 		imon_incoming_packet(ictx, urb, intfnum);
1735 		break;
1736 
1737 	default:
1738 		dev_warn(ictx->dev, "imon %s: status(%d): ignored\n",
1739 			 __func__, urb->status);
1740 		break;
1741 	}
1742 
1743 out:
1744 	usb_submit_urb(ictx->rx_urb_intf0, GFP_ATOMIC);
1745 }
1746 
1747 static void usb_rx_callback_intf1(struct urb *urb)
1748 {
1749 	struct imon_context *ictx;
1750 	int intfnum = 1;
1751 
1752 	if (!urb)
1753 		return;
1754 
1755 	ictx = (struct imon_context *)urb->context;
1756 	if (!ictx)
1757 		return;
1758 
1759 	/*
1760 	 * if we get a callback before we're done configuring the hardware, we
1761 	 * can't yet process the data, as there's nowhere to send it, but we
1762 	 * still need to submit a new rx URB to avoid wedging the hardware
1763 	 */
1764 	if (!ictx->dev_present_intf1)
1765 		goto out;
1766 
1767 	switch (urb->status) {
1768 	case -ENOENT:		/* usbcore unlink successful! */
1769 		return;
1770 
1771 	case -ESHUTDOWN:	/* transport endpoint was shut down */
1772 		break;
1773 
1774 	case 0:
1775 		imon_incoming_packet(ictx, urb, intfnum);
1776 		break;
1777 
1778 	default:
1779 		dev_warn(ictx->dev, "imon %s: status(%d): ignored\n",
1780 			 __func__, urb->status);
1781 		break;
1782 	}
1783 
1784 out:
1785 	usb_submit_urb(ictx->rx_urb_intf1, GFP_ATOMIC);
1786 }
1787 
1788 /*
1789  * The 0x15c2:0xffdc device ID was used for umpteen different imon
1790  * devices, and all of them constantly spew interrupts, even when there
1791  * is no actual data to report. However, byte 6 of this buffer looks like
1792  * its unique across device variants, so we're trying to key off that to
1793  * figure out which display type (if any) and what IR protocol the device
1794  * actually supports. These devices have their IR protocol hard-coded into
1795  * their firmware, they can't be changed on the fly like the newer hardware.
1796  */
1797 static void imon_get_ffdc_type(struct imon_context *ictx)
1798 {
1799 	u8 ffdc_cfg_byte = ictx->usb_rx_buf[6];
1800 	u8 detected_display_type = IMON_DISPLAY_TYPE_NONE;
1801 	u64 allowed_protos = RC_PROTO_BIT_IMON;
1802 
1803 	switch (ffdc_cfg_byte) {
1804 	/* iMON Knob, no display, iMON IR + vol knob */
1805 	case 0x21:
1806 		dev_info(ictx->dev, "0xffdc iMON Knob, iMON IR");
1807 		ictx->display_supported = false;
1808 		break;
1809 	/* iMON 2.4G LT (usb stick), no display, iMON RF */
1810 	case 0x4e:
1811 		dev_info(ictx->dev, "0xffdc iMON 2.4G LT, iMON RF");
1812 		ictx->display_supported = false;
1813 		ictx->rf_device = true;
1814 		break;
1815 	/* iMON VFD, no IR (does have vol knob tho) */
1816 	case 0x35:
1817 		dev_info(ictx->dev, "0xffdc iMON VFD + knob, no IR");
1818 		detected_display_type = IMON_DISPLAY_TYPE_VFD;
1819 		break;
1820 	/* iMON VFD, iMON IR */
1821 	case 0x24:
1822 	case 0x30:
1823 	case 0x85:
1824 		dev_info(ictx->dev, "0xffdc iMON VFD, iMON IR");
1825 		detected_display_type = IMON_DISPLAY_TYPE_VFD;
1826 		break;
1827 	/* iMON VFD, MCE IR */
1828 	case 0x46:
1829 	case 0x9e:
1830 		dev_info(ictx->dev, "0xffdc iMON VFD, MCE IR");
1831 		detected_display_type = IMON_DISPLAY_TYPE_VFD;
1832 		allowed_protos = RC_PROTO_BIT_RC6_MCE;
1833 		break;
1834 	/* iMON VFD, iMON or MCE IR */
1835 	case 0x7e:
1836 		dev_info(ictx->dev, "0xffdc iMON VFD, iMON or MCE IR");
1837 		detected_display_type = IMON_DISPLAY_TYPE_VFD;
1838 		allowed_protos |= RC_PROTO_BIT_RC6_MCE;
1839 		break;
1840 	/* iMON LCD, MCE IR */
1841 	case 0x9f:
1842 		dev_info(ictx->dev, "0xffdc iMON LCD, MCE IR");
1843 		detected_display_type = IMON_DISPLAY_TYPE_LCD;
1844 		allowed_protos = RC_PROTO_BIT_RC6_MCE;
1845 		break;
1846 	/* no display, iMON IR */
1847 	case 0x26:
1848 		dev_info(ictx->dev, "0xffdc iMON Inside, iMON IR");
1849 		ictx->display_supported = false;
1850 		break;
1851 	default:
1852 		dev_info(ictx->dev, "Unknown 0xffdc device, defaulting to VFD and iMON IR");
1853 		detected_display_type = IMON_DISPLAY_TYPE_VFD;
1854 		/*
1855 		 * We don't know which one it is, allow user to set the
1856 		 * RC6 one from userspace if IMON wasn't correct.
1857 		 */
1858 		allowed_protos |= RC_PROTO_BIT_RC6_MCE;
1859 		break;
1860 	}
1861 
1862 	printk(KERN_CONT " (id 0x%02x)\n", ffdc_cfg_byte);
1863 
1864 	ictx->display_type = detected_display_type;
1865 	ictx->rc_proto = allowed_protos;
1866 }
1867 
1868 static void imon_set_display_type(struct imon_context *ictx)
1869 {
1870 	u8 configured_display_type = IMON_DISPLAY_TYPE_VFD;
1871 
1872 	/*
1873 	 * Try to auto-detect the type of display if the user hasn't set
1874 	 * it by hand via the display_type modparam. Default is VFD.
1875 	 */
1876 
1877 	if (display_type == IMON_DISPLAY_TYPE_AUTO) {
1878 		switch (ictx->product) {
1879 		case 0xffdc:
1880 			/* set in imon_get_ffdc_type() */
1881 			configured_display_type = ictx->display_type;
1882 			break;
1883 		case 0x0034:
1884 		case 0x0035:
1885 			configured_display_type = IMON_DISPLAY_TYPE_VGA;
1886 			break;
1887 		case 0x0038:
1888 		case 0x0039:
1889 		case 0x0045:
1890 			configured_display_type = IMON_DISPLAY_TYPE_LCD;
1891 			break;
1892 		case 0x003c:
1893 		case 0x0041:
1894 		case 0x0042:
1895 		case 0x0043:
1896 			configured_display_type = IMON_DISPLAY_TYPE_NONE;
1897 			ictx->display_supported = false;
1898 			break;
1899 		case 0x0036:
1900 		case 0x0044:
1901 		default:
1902 			configured_display_type = IMON_DISPLAY_TYPE_VFD;
1903 			break;
1904 		}
1905 	} else {
1906 		configured_display_type = display_type;
1907 		if (display_type == IMON_DISPLAY_TYPE_NONE)
1908 			ictx->display_supported = false;
1909 		else
1910 			ictx->display_supported = true;
1911 		dev_info(ictx->dev, "%s: overriding display type to %d via modparam\n",
1912 			 __func__, display_type);
1913 	}
1914 
1915 	ictx->display_type = configured_display_type;
1916 }
1917 
1918 static struct rc_dev *imon_init_rdev(struct imon_context *ictx)
1919 {
1920 	struct rc_dev *rdev;
1921 	int ret;
1922 	static const unsigned char fp_packet[] = {
1923 		0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x88 };
1924 
1925 	rdev = rc_allocate_device(RC_DRIVER_SCANCODE);
1926 	if (!rdev) {
1927 		dev_err(ictx->dev, "remote control dev allocation failed\n");
1928 		goto out;
1929 	}
1930 
1931 	snprintf(ictx->name_rdev, sizeof(ictx->name_rdev),
1932 		 "iMON Remote (%04x:%04x)", ictx->vendor, ictx->product);
1933 	usb_make_path(ictx->usbdev_intf0, ictx->phys_rdev,
1934 		      sizeof(ictx->phys_rdev));
1935 	strlcat(ictx->phys_rdev, "/input0", sizeof(ictx->phys_rdev));
1936 
1937 	rdev->device_name = ictx->name_rdev;
1938 	rdev->input_phys = ictx->phys_rdev;
1939 	usb_to_input_id(ictx->usbdev_intf0, &rdev->input_id);
1940 	rdev->dev.parent = ictx->dev;
1941 
1942 	rdev->priv = ictx;
1943 	/* iMON PAD or MCE */
1944 	rdev->allowed_protocols = RC_PROTO_BIT_IMON | RC_PROTO_BIT_RC6_MCE;
1945 	rdev->change_protocol = imon_ir_change_protocol;
1946 	rdev->driver_name = MOD_NAME;
1947 
1948 	/* Enable front-panel buttons and/or knobs */
1949 	memcpy(ictx->usb_tx_buf, &fp_packet, sizeof(fp_packet));
1950 	ret = send_packet(ictx);
1951 	/* Not fatal, but warn about it */
1952 	if (ret)
1953 		dev_info(ictx->dev, "panel buttons/knobs setup failed\n");
1954 
1955 	if (ictx->product == 0xffdc) {
1956 		imon_get_ffdc_type(ictx);
1957 		rdev->allowed_protocols = ictx->rc_proto;
1958 	}
1959 
1960 	imon_set_display_type(ictx);
1961 
1962 	if (ictx->rc_proto == RC_PROTO_BIT_RC6_MCE)
1963 		rdev->map_name = RC_MAP_IMON_MCE;
1964 	else
1965 		rdev->map_name = RC_MAP_IMON_PAD;
1966 
1967 	ret = rc_register_device(rdev);
1968 	if (ret < 0) {
1969 		dev_err(ictx->dev, "remote input dev register failed\n");
1970 		goto out;
1971 	}
1972 
1973 	return rdev;
1974 
1975 out:
1976 	rc_free_device(rdev);
1977 	return NULL;
1978 }
1979 
1980 static struct input_dev *imon_init_idev(struct imon_context *ictx)
1981 {
1982 	struct imon_panel_key_table *key_table = ictx->dev_descr->key_table;
1983 	struct input_dev *idev;
1984 	int ret, i;
1985 
1986 	idev = input_allocate_device();
1987 	if (!idev)
1988 		goto out;
1989 
1990 	snprintf(ictx->name_idev, sizeof(ictx->name_idev),
1991 		 "iMON Panel, Knob and Mouse(%04x:%04x)",
1992 		 ictx->vendor, ictx->product);
1993 	idev->name = ictx->name_idev;
1994 
1995 	usb_make_path(ictx->usbdev_intf0, ictx->phys_idev,
1996 		      sizeof(ictx->phys_idev));
1997 	strlcat(ictx->phys_idev, "/input1", sizeof(ictx->phys_idev));
1998 	idev->phys = ictx->phys_idev;
1999 
2000 	idev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP) | BIT_MASK(EV_REL);
2001 
2002 	idev->keybit[BIT_WORD(BTN_MOUSE)] =
2003 		BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_RIGHT);
2004 	idev->relbit[0] = BIT_MASK(REL_X) | BIT_MASK(REL_Y) |
2005 		BIT_MASK(REL_WHEEL);
2006 
2007 	/* panel and/or knob code support */
2008 	for (i = 0; key_table[i].hw_code != 0; i++) {
2009 		u32 kc = key_table[i].keycode;
2010 		__set_bit(kc, idev->keybit);
2011 	}
2012 
2013 	usb_to_input_id(ictx->usbdev_intf0, &idev->id);
2014 	idev->dev.parent = ictx->dev;
2015 	input_set_drvdata(idev, ictx);
2016 
2017 	ret = input_register_device(idev);
2018 	if (ret < 0) {
2019 		dev_err(ictx->dev, "input dev register failed\n");
2020 		goto out;
2021 	}
2022 
2023 	return idev;
2024 
2025 out:
2026 	input_free_device(idev);
2027 	return NULL;
2028 }
2029 
2030 static struct input_dev *imon_init_touch(struct imon_context *ictx)
2031 {
2032 	struct input_dev *touch;
2033 	int ret;
2034 
2035 	touch = input_allocate_device();
2036 	if (!touch)
2037 		goto touch_alloc_failed;
2038 
2039 	snprintf(ictx->name_touch, sizeof(ictx->name_touch),
2040 		 "iMON USB Touchscreen (%04x:%04x)",
2041 		 ictx->vendor, ictx->product);
2042 	touch->name = ictx->name_touch;
2043 
2044 	usb_make_path(ictx->usbdev_intf1, ictx->phys_touch,
2045 		      sizeof(ictx->phys_touch));
2046 	strlcat(ictx->phys_touch, "/input2", sizeof(ictx->phys_touch));
2047 	touch->phys = ictx->phys_touch;
2048 
2049 	touch->evbit[0] =
2050 		BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
2051 	touch->keybit[BIT_WORD(BTN_TOUCH)] =
2052 		BIT_MASK(BTN_TOUCH);
2053 	input_set_abs_params(touch, ABS_X,
2054 			     0x00, 0xfff, 0, 0);
2055 	input_set_abs_params(touch, ABS_Y,
2056 			     0x00, 0xfff, 0, 0);
2057 
2058 	input_set_drvdata(touch, ictx);
2059 
2060 	usb_to_input_id(ictx->usbdev_intf1, &touch->id);
2061 	touch->dev.parent = ictx->dev;
2062 	ret = input_register_device(touch);
2063 	if (ret <  0) {
2064 		dev_info(ictx->dev, "touchscreen input dev register failed\n");
2065 		goto touch_register_failed;
2066 	}
2067 
2068 	return touch;
2069 
2070 touch_register_failed:
2071 	input_free_device(touch);
2072 
2073 touch_alloc_failed:
2074 	return NULL;
2075 }
2076 
2077 static bool imon_find_endpoints(struct imon_context *ictx,
2078 				struct usb_host_interface *iface_desc)
2079 {
2080 	struct usb_endpoint_descriptor *ep;
2081 	struct usb_endpoint_descriptor *rx_endpoint = NULL;
2082 	struct usb_endpoint_descriptor *tx_endpoint = NULL;
2083 	int ifnum = iface_desc->desc.bInterfaceNumber;
2084 	int num_endpts = iface_desc->desc.bNumEndpoints;
2085 	int i, ep_dir, ep_type;
2086 	bool ir_ep_found = false;
2087 	bool display_ep_found = false;
2088 	bool tx_control = false;
2089 
2090 	/*
2091 	 * Scan the endpoint list and set:
2092 	 *	first input endpoint = IR endpoint
2093 	 *	first output endpoint = display endpoint
2094 	 */
2095 	for (i = 0; i < num_endpts && !(ir_ep_found && display_ep_found); ++i) {
2096 		ep = &iface_desc->endpoint[i].desc;
2097 		ep_dir = ep->bEndpointAddress & USB_ENDPOINT_DIR_MASK;
2098 		ep_type = usb_endpoint_type(ep);
2099 
2100 		if (!ir_ep_found && ep_dir == USB_DIR_IN &&
2101 		    ep_type == USB_ENDPOINT_XFER_INT) {
2102 
2103 			rx_endpoint = ep;
2104 			ir_ep_found = true;
2105 			dev_dbg(ictx->dev, "%s: found IR endpoint\n", __func__);
2106 
2107 		} else if (!display_ep_found && ep_dir == USB_DIR_OUT &&
2108 			   ep_type == USB_ENDPOINT_XFER_INT) {
2109 			tx_endpoint = ep;
2110 			display_ep_found = true;
2111 			dev_dbg(ictx->dev, "%s: found display endpoint\n", __func__);
2112 		}
2113 	}
2114 
2115 	if (ifnum == 0) {
2116 		ictx->rx_endpoint_intf0 = rx_endpoint;
2117 		/*
2118 		 * tx is used to send characters to lcd/vfd, associate RF
2119 		 * remotes, set IR protocol, and maybe more...
2120 		 */
2121 		ictx->tx_endpoint = tx_endpoint;
2122 	} else {
2123 		ictx->rx_endpoint_intf1 = rx_endpoint;
2124 	}
2125 
2126 	/*
2127 	 * If we didn't find a display endpoint, this is probably one of the
2128 	 * newer iMON devices that use control urb instead of interrupt
2129 	 */
2130 	if (!display_ep_found) {
2131 		tx_control = true;
2132 		display_ep_found = true;
2133 		dev_dbg(ictx->dev, "%s: device uses control endpoint, not interface OUT endpoint\n",
2134 			__func__);
2135 	}
2136 
2137 	/*
2138 	 * Some iMON receivers have no display. Unfortunately, it seems
2139 	 * that SoundGraph recycles device IDs between devices both with
2140 	 * and without... :\
2141 	 */
2142 	if (ictx->display_type == IMON_DISPLAY_TYPE_NONE) {
2143 		display_ep_found = false;
2144 		dev_dbg(ictx->dev, "%s: device has no display\n", __func__);
2145 	}
2146 
2147 	/*
2148 	 * iMON Touch devices have a VGA touchscreen, but no "display", as
2149 	 * that refers to e.g. /dev/lcd0 (a character device LCD or VFD).
2150 	 */
2151 	if (ictx->display_type == IMON_DISPLAY_TYPE_VGA) {
2152 		display_ep_found = false;
2153 		dev_dbg(ictx->dev, "%s: iMON Touch device found\n", __func__);
2154 	}
2155 
2156 	/* Input endpoint is mandatory */
2157 	if (!ir_ep_found)
2158 		pr_err("no valid input (IR) endpoint found\n");
2159 
2160 	ictx->tx_control = tx_control;
2161 
2162 	if (display_ep_found)
2163 		ictx->display_supported = true;
2164 
2165 	return ir_ep_found;
2166 
2167 }
2168 
2169 static struct imon_context *imon_init_intf0(struct usb_interface *intf,
2170 					    const struct usb_device_id *id)
2171 {
2172 	struct imon_context *ictx;
2173 	struct urb *rx_urb;
2174 	struct urb *tx_urb;
2175 	struct device *dev = &intf->dev;
2176 	struct usb_host_interface *iface_desc;
2177 	int ret = -ENOMEM;
2178 
2179 	ictx = kzalloc(sizeof(*ictx), GFP_KERNEL);
2180 	if (!ictx)
2181 		goto exit;
2182 
2183 	rx_urb = usb_alloc_urb(0, GFP_KERNEL);
2184 	if (!rx_urb)
2185 		goto rx_urb_alloc_failed;
2186 	tx_urb = usb_alloc_urb(0, GFP_KERNEL);
2187 	if (!tx_urb)
2188 		goto tx_urb_alloc_failed;
2189 
2190 	mutex_init(&ictx->lock);
2191 	spin_lock_init(&ictx->kc_lock);
2192 
2193 	mutex_lock(&ictx->lock);
2194 
2195 	ictx->dev = dev;
2196 	ictx->usbdev_intf0 = usb_get_dev(interface_to_usbdev(intf));
2197 	ictx->rx_urb_intf0 = rx_urb;
2198 	ictx->tx_urb = tx_urb;
2199 	ictx->rf_device = false;
2200 
2201 	init_completion(&ictx->tx.finished);
2202 
2203 	ictx->vendor  = le16_to_cpu(ictx->usbdev_intf0->descriptor.idVendor);
2204 	ictx->product = le16_to_cpu(ictx->usbdev_intf0->descriptor.idProduct);
2205 
2206 	/* save drive info for later accessing the panel/knob key table */
2207 	ictx->dev_descr = (struct imon_usb_dev_descr *)id->driver_info;
2208 	/* default send_packet delay is 5ms but some devices need more */
2209 	ictx->send_packet_delay = ictx->dev_descr->flags &
2210 				  IMON_NEED_20MS_PKT_DELAY ? 20 : 5;
2211 
2212 	ret = -ENODEV;
2213 	iface_desc = intf->cur_altsetting;
2214 	if (!imon_find_endpoints(ictx, iface_desc)) {
2215 		goto find_endpoint_failed;
2216 	}
2217 
2218 	usb_fill_int_urb(ictx->rx_urb_intf0, ictx->usbdev_intf0,
2219 		usb_rcvintpipe(ictx->usbdev_intf0,
2220 			ictx->rx_endpoint_intf0->bEndpointAddress),
2221 		ictx->usb_rx_buf, sizeof(ictx->usb_rx_buf),
2222 		usb_rx_callback_intf0, ictx,
2223 		ictx->rx_endpoint_intf0->bInterval);
2224 
2225 	ret = usb_submit_urb(ictx->rx_urb_intf0, GFP_KERNEL);
2226 	if (ret) {
2227 		pr_err("usb_submit_urb failed for intf0 (%d)\n", ret);
2228 		goto urb_submit_failed;
2229 	}
2230 
2231 	ictx->idev = imon_init_idev(ictx);
2232 	if (!ictx->idev) {
2233 		dev_err(dev, "%s: input device setup failed\n", __func__);
2234 		goto idev_setup_failed;
2235 	}
2236 
2237 	ictx->rdev = imon_init_rdev(ictx);
2238 	if (!ictx->rdev) {
2239 		dev_err(dev, "%s: rc device setup failed\n", __func__);
2240 		goto rdev_setup_failed;
2241 	}
2242 
2243 	ictx->dev_present_intf0 = true;
2244 
2245 	mutex_unlock(&ictx->lock);
2246 	return ictx;
2247 
2248 rdev_setup_failed:
2249 	input_unregister_device(ictx->idev);
2250 idev_setup_failed:
2251 	usb_kill_urb(ictx->rx_urb_intf0);
2252 urb_submit_failed:
2253 find_endpoint_failed:
2254 	usb_put_dev(ictx->usbdev_intf0);
2255 	mutex_unlock(&ictx->lock);
2256 	usb_free_urb(tx_urb);
2257 tx_urb_alloc_failed:
2258 	usb_free_urb(rx_urb);
2259 rx_urb_alloc_failed:
2260 	kfree(ictx);
2261 exit:
2262 	dev_err(dev, "unable to initialize intf0, err %d\n", ret);
2263 
2264 	return NULL;
2265 }
2266 
2267 static struct imon_context *imon_init_intf1(struct usb_interface *intf,
2268 					    struct imon_context *ictx)
2269 {
2270 	struct urb *rx_urb;
2271 	struct usb_host_interface *iface_desc;
2272 	int ret = -ENOMEM;
2273 
2274 	rx_urb = usb_alloc_urb(0, GFP_KERNEL);
2275 	if (!rx_urb)
2276 		goto rx_urb_alloc_failed;
2277 
2278 	mutex_lock(&ictx->lock);
2279 
2280 	if (ictx->display_type == IMON_DISPLAY_TYPE_VGA) {
2281 		timer_setup(&ictx->ttimer, imon_touch_display_timeout, 0);
2282 	}
2283 
2284 	ictx->usbdev_intf1 = usb_get_dev(interface_to_usbdev(intf));
2285 	ictx->rx_urb_intf1 = rx_urb;
2286 
2287 	ret = -ENODEV;
2288 	iface_desc = intf->cur_altsetting;
2289 	if (!imon_find_endpoints(ictx, iface_desc))
2290 		goto find_endpoint_failed;
2291 
2292 	if (ictx->display_type == IMON_DISPLAY_TYPE_VGA) {
2293 		ictx->touch = imon_init_touch(ictx);
2294 		if (!ictx->touch)
2295 			goto touch_setup_failed;
2296 	} else
2297 		ictx->touch = NULL;
2298 
2299 	usb_fill_int_urb(ictx->rx_urb_intf1, ictx->usbdev_intf1,
2300 		usb_rcvintpipe(ictx->usbdev_intf1,
2301 			ictx->rx_endpoint_intf1->bEndpointAddress),
2302 		ictx->usb_rx_buf, sizeof(ictx->usb_rx_buf),
2303 		usb_rx_callback_intf1, ictx,
2304 		ictx->rx_endpoint_intf1->bInterval);
2305 
2306 	ret = usb_submit_urb(ictx->rx_urb_intf1, GFP_KERNEL);
2307 
2308 	if (ret) {
2309 		pr_err("usb_submit_urb failed for intf1 (%d)\n", ret);
2310 		goto urb_submit_failed;
2311 	}
2312 
2313 	ictx->dev_present_intf1 = true;
2314 
2315 	mutex_unlock(&ictx->lock);
2316 	return ictx;
2317 
2318 urb_submit_failed:
2319 	if (ictx->touch)
2320 		input_unregister_device(ictx->touch);
2321 touch_setup_failed:
2322 find_endpoint_failed:
2323 	usb_put_dev(ictx->usbdev_intf1);
2324 	mutex_unlock(&ictx->lock);
2325 	usb_free_urb(rx_urb);
2326 rx_urb_alloc_failed:
2327 	dev_err(ictx->dev, "unable to initialize intf1, err %d\n", ret);
2328 
2329 	return NULL;
2330 }
2331 
2332 static void imon_init_display(struct imon_context *ictx,
2333 			      struct usb_interface *intf)
2334 {
2335 	int ret;
2336 
2337 	dev_dbg(ictx->dev, "Registering iMON display with sysfs\n");
2338 
2339 	/* set up sysfs entry for built-in clock */
2340 	ret = sysfs_create_group(&intf->dev.kobj, &imon_display_attr_group);
2341 	if (ret)
2342 		dev_err(ictx->dev, "Could not create display sysfs entries(%d)",
2343 			ret);
2344 
2345 	if (ictx->display_type == IMON_DISPLAY_TYPE_LCD)
2346 		ret = usb_register_dev(intf, &imon_lcd_class);
2347 	else
2348 		ret = usb_register_dev(intf, &imon_vfd_class);
2349 	if (ret)
2350 		/* Not a fatal error, so ignore */
2351 		dev_info(ictx->dev, "could not get a minor number for display\n");
2352 
2353 }
2354 
2355 /*
2356  * Callback function for USB core API: Probe
2357  */
2358 static int imon_probe(struct usb_interface *interface,
2359 		      const struct usb_device_id *id)
2360 {
2361 	struct usb_device *usbdev = NULL;
2362 	struct usb_host_interface *iface_desc = NULL;
2363 	struct usb_interface *first_if;
2364 	struct device *dev = &interface->dev;
2365 	int ifnum, sysfs_err;
2366 	int ret = 0;
2367 	struct imon_context *ictx = NULL;
2368 	struct imon_context *first_if_ctx = NULL;
2369 	u16 vendor, product;
2370 
2371 	usbdev     = usb_get_dev(interface_to_usbdev(interface));
2372 	iface_desc = interface->cur_altsetting;
2373 	ifnum      = iface_desc->desc.bInterfaceNumber;
2374 	vendor     = le16_to_cpu(usbdev->descriptor.idVendor);
2375 	product    = le16_to_cpu(usbdev->descriptor.idProduct);
2376 
2377 	dev_dbg(dev, "%s: found iMON device (%04x:%04x, intf%d)\n",
2378 		__func__, vendor, product, ifnum);
2379 
2380 	/* prevent races probing devices w/multiple interfaces */
2381 	mutex_lock(&driver_lock);
2382 
2383 	first_if = usb_ifnum_to_if(usbdev, 0);
2384 	if (!first_if) {
2385 		ret = -ENODEV;
2386 		goto fail;
2387 	}
2388 
2389 	first_if_ctx = usb_get_intfdata(first_if);
2390 
2391 	if (ifnum == 0) {
2392 		ictx = imon_init_intf0(interface, id);
2393 		if (!ictx) {
2394 			pr_err("failed to initialize context!\n");
2395 			ret = -ENODEV;
2396 			goto fail;
2397 		}
2398 
2399 	} else {
2400 		/* this is the secondary interface on the device */
2401 
2402 		/* fail early if first intf failed to register */
2403 		if (!first_if_ctx) {
2404 			ret = -ENODEV;
2405 			goto fail;
2406 		}
2407 
2408 		ictx = imon_init_intf1(interface, first_if_ctx);
2409 		if (!ictx) {
2410 			pr_err("failed to attach to context!\n");
2411 			ret = -ENODEV;
2412 			goto fail;
2413 		}
2414 
2415 	}
2416 
2417 	usb_set_intfdata(interface, ictx);
2418 
2419 	if (ifnum == 0) {
2420 		mutex_lock(&ictx->lock);
2421 
2422 		if (product == 0xffdc && ictx->rf_device) {
2423 			sysfs_err = sysfs_create_group(&interface->dev.kobj,
2424 						       &imon_rf_attr_group);
2425 			if (sysfs_err)
2426 				pr_err("Could not create RF sysfs entries(%d)\n",
2427 				       sysfs_err);
2428 		}
2429 
2430 		if (ictx->display_supported)
2431 			imon_init_display(ictx, interface);
2432 
2433 		mutex_unlock(&ictx->lock);
2434 	}
2435 
2436 	dev_info(dev, "iMON device (%04x:%04x, intf%d) on usb<%d:%d> initialized\n",
2437 		 vendor, product, ifnum,
2438 		 usbdev->bus->busnum, usbdev->devnum);
2439 
2440 	mutex_unlock(&driver_lock);
2441 	usb_put_dev(usbdev);
2442 
2443 	return 0;
2444 
2445 fail:
2446 	mutex_unlock(&driver_lock);
2447 	usb_put_dev(usbdev);
2448 	dev_err(dev, "unable to register, err %d\n", ret);
2449 
2450 	return ret;
2451 }
2452 
2453 /*
2454  * Callback function for USB core API: disconnect
2455  */
2456 static void imon_disconnect(struct usb_interface *interface)
2457 {
2458 	struct imon_context *ictx;
2459 	struct device *dev;
2460 	int ifnum;
2461 
2462 	/* prevent races with multi-interface device probing and display_open */
2463 	mutex_lock(&driver_lock);
2464 
2465 	ictx = usb_get_intfdata(interface);
2466 	dev = ictx->dev;
2467 	ifnum = interface->cur_altsetting->desc.bInterfaceNumber;
2468 
2469 	/*
2470 	 * sysfs_remove_group is safe to call even if sysfs_create_group
2471 	 * hasn't been called
2472 	 */
2473 	sysfs_remove_group(&interface->dev.kobj, &imon_display_attr_group);
2474 	sysfs_remove_group(&interface->dev.kobj, &imon_rf_attr_group);
2475 
2476 	usb_set_intfdata(interface, NULL);
2477 
2478 	/* Abort ongoing write */
2479 	if (ictx->tx.busy) {
2480 		usb_kill_urb(ictx->tx_urb);
2481 		complete(&ictx->tx.finished);
2482 	}
2483 
2484 	if (ifnum == 0) {
2485 		ictx->dev_present_intf0 = false;
2486 		usb_kill_urb(ictx->rx_urb_intf0);
2487 		usb_put_dev(ictx->usbdev_intf0);
2488 		input_unregister_device(ictx->idev);
2489 		rc_unregister_device(ictx->rdev);
2490 		if (ictx->display_supported) {
2491 			if (ictx->display_type == IMON_DISPLAY_TYPE_LCD)
2492 				usb_deregister_dev(interface, &imon_lcd_class);
2493 			else if (ictx->display_type == IMON_DISPLAY_TYPE_VFD)
2494 				usb_deregister_dev(interface, &imon_vfd_class);
2495 		}
2496 	} else {
2497 		ictx->dev_present_intf1 = false;
2498 		usb_kill_urb(ictx->rx_urb_intf1);
2499 		usb_put_dev(ictx->usbdev_intf1);
2500 		if (ictx->display_type == IMON_DISPLAY_TYPE_VGA) {
2501 			input_unregister_device(ictx->touch);
2502 			del_timer_sync(&ictx->ttimer);
2503 		}
2504 	}
2505 
2506 	if (!ictx->dev_present_intf0 && !ictx->dev_present_intf1)
2507 		free_imon_context(ictx);
2508 
2509 	mutex_unlock(&driver_lock);
2510 
2511 	dev_dbg(dev, "%s: iMON device (intf%d) disconnected\n",
2512 		__func__, ifnum);
2513 }
2514 
2515 static int imon_suspend(struct usb_interface *intf, pm_message_t message)
2516 {
2517 	struct imon_context *ictx = usb_get_intfdata(intf);
2518 	int ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
2519 
2520 	if (ifnum == 0)
2521 		usb_kill_urb(ictx->rx_urb_intf0);
2522 	else
2523 		usb_kill_urb(ictx->rx_urb_intf1);
2524 
2525 	return 0;
2526 }
2527 
2528 static int imon_resume(struct usb_interface *intf)
2529 {
2530 	int rc = 0;
2531 	struct imon_context *ictx = usb_get_intfdata(intf);
2532 	int ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
2533 
2534 	if (ifnum == 0) {
2535 		usb_fill_int_urb(ictx->rx_urb_intf0, ictx->usbdev_intf0,
2536 			usb_rcvintpipe(ictx->usbdev_intf0,
2537 				ictx->rx_endpoint_intf0->bEndpointAddress),
2538 			ictx->usb_rx_buf, sizeof(ictx->usb_rx_buf),
2539 			usb_rx_callback_intf0, ictx,
2540 			ictx->rx_endpoint_intf0->bInterval);
2541 
2542 		rc = usb_submit_urb(ictx->rx_urb_intf0, GFP_ATOMIC);
2543 
2544 	} else {
2545 		usb_fill_int_urb(ictx->rx_urb_intf1, ictx->usbdev_intf1,
2546 			usb_rcvintpipe(ictx->usbdev_intf1,
2547 				ictx->rx_endpoint_intf1->bEndpointAddress),
2548 			ictx->usb_rx_buf, sizeof(ictx->usb_rx_buf),
2549 			usb_rx_callback_intf1, ictx,
2550 			ictx->rx_endpoint_intf1->bInterval);
2551 
2552 		rc = usb_submit_urb(ictx->rx_urb_intf1, GFP_ATOMIC);
2553 	}
2554 
2555 	return rc;
2556 }
2557 
2558 module_usb_driver(imon_driver);
2559