xref: /linux/drivers/media/rc/imon.c (revision 87c9c16317882dd6dbbc07e349bc3223e14f3244)
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 #define IMON_SUPPRESS_REPEATED_KEYS 2
87 	struct imon_panel_key_table key_table[];
88 };
89 
90 struct imon_context {
91 	struct device *dev;
92 	/* Newer devices have two interfaces */
93 	struct usb_device *usbdev_intf0;
94 	struct usb_device *usbdev_intf1;
95 
96 	bool display_supported;		/* not all controllers do */
97 	bool display_isopen;		/* display port has been opened */
98 	bool rf_device;			/* true if iMON 2.4G LT/DT RF device */
99 	bool rf_isassociating;		/* RF remote associating */
100 	bool dev_present_intf0;		/* USB device presence, interface 0 */
101 	bool dev_present_intf1;		/* USB device presence, interface 1 */
102 
103 	struct mutex lock;		/* to lock this object */
104 	wait_queue_head_t remove_ok;	/* For unexpected USB disconnects */
105 
106 	struct usb_endpoint_descriptor *rx_endpoint_intf0;
107 	struct usb_endpoint_descriptor *rx_endpoint_intf1;
108 	struct usb_endpoint_descriptor *tx_endpoint;
109 	struct urb *rx_urb_intf0;
110 	struct urb *rx_urb_intf1;
111 	struct urb *tx_urb;
112 	bool tx_control;
113 	unsigned char usb_rx_buf[8];
114 	unsigned char usb_tx_buf[8];
115 	unsigned int send_packet_delay;
116 
117 	struct tx_t {
118 		unsigned char data_buf[35];	/* user data buffer */
119 		struct completion finished;	/* wait for write to finish */
120 		bool busy;			/* write in progress */
121 		int status;			/* status of tx completion */
122 	} tx;
123 
124 	u16 vendor;			/* usb vendor ID */
125 	u16 product;			/* usb product ID */
126 
127 	struct rc_dev *rdev;		/* rc-core device for remote */
128 	struct input_dev *idev;		/* input device for panel & IR mouse */
129 	struct input_dev *touch;	/* input device for touchscreen */
130 
131 	spinlock_t kc_lock;		/* make sure we get keycodes right */
132 	u32 kc;				/* current input keycode */
133 	u32 last_keycode;		/* last reported input keycode */
134 	u32 rc_scancode;		/* the computed remote scancode */
135 	u8 rc_toggle;			/* the computed remote toggle bit */
136 	u64 rc_proto;			/* iMON or MCE (RC6) IR protocol? */
137 	bool release_code;		/* some keys send a release code */
138 
139 	u8 display_type;		/* store the display type */
140 	bool pad_mouse;			/* toggle kbd(0)/mouse(1) mode */
141 
142 	char name_rdev[128];		/* rc input device name */
143 	char phys_rdev[64];		/* rc input device phys path */
144 
145 	char name_idev[128];		/* input device name */
146 	char phys_idev[64];		/* input device phys path */
147 
148 	char name_touch[128];		/* touch screen name */
149 	char phys_touch[64];		/* touch screen phys path */
150 	struct timer_list ttimer;	/* touch screen timer */
151 	int touch_x;			/* x coordinate on touchscreen */
152 	int touch_y;			/* y coordinate on touchscreen */
153 	const struct imon_usb_dev_descr *dev_descr;
154 					/* device description with key */
155 					/* table for front panels */
156 };
157 
158 #define TOUCH_TIMEOUT	(HZ/30)
159 
160 /* vfd character device file operations */
161 static const struct file_operations vfd_fops = {
162 	.owner		= THIS_MODULE,
163 	.open		= &display_open,
164 	.write		= &vfd_write,
165 	.release	= &display_close,
166 	.llseek		= noop_llseek,
167 };
168 
169 /* lcd character device file operations */
170 static const struct file_operations lcd_fops = {
171 	.owner		= THIS_MODULE,
172 	.open		= &display_open,
173 	.write		= &lcd_write,
174 	.release	= &display_close,
175 	.llseek		= noop_llseek,
176 };
177 
178 enum {
179 	IMON_DISPLAY_TYPE_AUTO = 0,
180 	IMON_DISPLAY_TYPE_VFD  = 1,
181 	IMON_DISPLAY_TYPE_LCD  = 2,
182 	IMON_DISPLAY_TYPE_VGA  = 3,
183 	IMON_DISPLAY_TYPE_NONE = 4,
184 };
185 
186 enum {
187 	IMON_KEY_IMON	= 0,
188 	IMON_KEY_MCE	= 1,
189 	IMON_KEY_PANEL	= 2,
190 };
191 
192 static struct usb_class_driver imon_vfd_class = {
193 	.name		= DEVICE_NAME,
194 	.fops		= &vfd_fops,
195 	.minor_base	= DISPLAY_MINOR_BASE,
196 };
197 
198 static struct usb_class_driver imon_lcd_class = {
199 	.name		= DEVICE_NAME,
200 	.fops		= &lcd_fops,
201 	.minor_base	= DISPLAY_MINOR_BASE,
202 };
203 
204 /* imon receiver front panel/knob key table */
205 static const struct imon_usb_dev_descr imon_default_table = {
206 	.flags = IMON_NO_FLAGS,
207 	.key_table = {
208 		{ 0x000000000f00ffeell, KEY_MEDIA }, /* Go */
209 		{ 0x000000001200ffeell, KEY_UP },
210 		{ 0x000000001300ffeell, KEY_DOWN },
211 		{ 0x000000001400ffeell, KEY_LEFT },
212 		{ 0x000000001500ffeell, KEY_RIGHT },
213 		{ 0x000000001600ffeell, KEY_ENTER },
214 		{ 0x000000001700ffeell, KEY_ESC },
215 		{ 0x000000001f00ffeell, KEY_AUDIO },
216 		{ 0x000000002000ffeell, KEY_VIDEO },
217 		{ 0x000000002100ffeell, KEY_CAMERA },
218 		{ 0x000000002700ffeell, KEY_DVD },
219 		{ 0x000000002300ffeell, KEY_TV },
220 		{ 0x000000002b00ffeell, KEY_EXIT },
221 		{ 0x000000002c00ffeell, KEY_SELECT },
222 		{ 0x000000002d00ffeell, KEY_MENU },
223 		{ 0x000000000500ffeell, KEY_PREVIOUS },
224 		{ 0x000000000700ffeell, KEY_REWIND },
225 		{ 0x000000000400ffeell, KEY_STOP },
226 		{ 0x000000003c00ffeell, KEY_PLAYPAUSE },
227 		{ 0x000000000800ffeell, KEY_FASTFORWARD },
228 		{ 0x000000000600ffeell, KEY_NEXT },
229 		{ 0x000000010000ffeell, KEY_RIGHT },
230 		{ 0x000001000000ffeell, KEY_LEFT },
231 		{ 0x000000003d00ffeell, KEY_SELECT },
232 		{ 0x000100000000ffeell, KEY_VOLUMEUP },
233 		{ 0x010000000000ffeell, KEY_VOLUMEDOWN },
234 		{ 0x000000000100ffeell, KEY_MUTE },
235 		/* 0xffdc iMON MCE VFD */
236 		{ 0x00010000ffffffeell, KEY_VOLUMEUP },
237 		{ 0x01000000ffffffeell, KEY_VOLUMEDOWN },
238 		{ 0x00000001ffffffeell, KEY_MUTE },
239 		{ 0x0000000fffffffeell, KEY_MEDIA },
240 		{ 0x00000012ffffffeell, KEY_UP },
241 		{ 0x00000013ffffffeell, KEY_DOWN },
242 		{ 0x00000014ffffffeell, KEY_LEFT },
243 		{ 0x00000015ffffffeell, KEY_RIGHT },
244 		{ 0x00000016ffffffeell, KEY_ENTER },
245 		{ 0x00000017ffffffeell, KEY_ESC },
246 		/* iMON Knob values */
247 		{ 0x000100ffffffffeell, KEY_VOLUMEUP },
248 		{ 0x010000ffffffffeell, KEY_VOLUMEDOWN },
249 		{ 0x000008ffffffffeell, KEY_MUTE },
250 		{ 0, KEY_RESERVED },
251 	}
252 };
253 
254 static const struct imon_usb_dev_descr imon_OEM_VFD = {
255 	.flags = IMON_NEED_20MS_PKT_DELAY,
256 	.key_table = {
257 		{ 0x000000000f00ffeell, KEY_MEDIA }, /* Go */
258 		{ 0x000000001200ffeell, KEY_UP },
259 		{ 0x000000001300ffeell, KEY_DOWN },
260 		{ 0x000000001400ffeell, KEY_LEFT },
261 		{ 0x000000001500ffeell, KEY_RIGHT },
262 		{ 0x000000001600ffeell, KEY_ENTER },
263 		{ 0x000000001700ffeell, KEY_ESC },
264 		{ 0x000000001f00ffeell, KEY_AUDIO },
265 		{ 0x000000002b00ffeell, KEY_EXIT },
266 		{ 0x000000002c00ffeell, KEY_SELECT },
267 		{ 0x000000002d00ffeell, KEY_MENU },
268 		{ 0x000000000500ffeell, KEY_PREVIOUS },
269 		{ 0x000000000700ffeell, KEY_REWIND },
270 		{ 0x000000000400ffeell, KEY_STOP },
271 		{ 0x000000003c00ffeell, KEY_PLAYPAUSE },
272 		{ 0x000000000800ffeell, KEY_FASTFORWARD },
273 		{ 0x000000000600ffeell, KEY_NEXT },
274 		{ 0x000000010000ffeell, KEY_RIGHT },
275 		{ 0x000001000000ffeell, KEY_LEFT },
276 		{ 0x000000003d00ffeell, KEY_SELECT },
277 		{ 0x000100000000ffeell, KEY_VOLUMEUP },
278 		{ 0x010000000000ffeell, KEY_VOLUMEDOWN },
279 		{ 0x000000000100ffeell, KEY_MUTE },
280 		/* 0xffdc iMON MCE VFD */
281 		{ 0x00010000ffffffeell, KEY_VOLUMEUP },
282 		{ 0x01000000ffffffeell, KEY_VOLUMEDOWN },
283 		{ 0x00000001ffffffeell, KEY_MUTE },
284 		{ 0x0000000fffffffeell, KEY_MEDIA },
285 		{ 0x00000012ffffffeell, KEY_UP },
286 		{ 0x00000013ffffffeell, KEY_DOWN },
287 		{ 0x00000014ffffffeell, KEY_LEFT },
288 		{ 0x00000015ffffffeell, KEY_RIGHT },
289 		{ 0x00000016ffffffeell, KEY_ENTER },
290 		{ 0x00000017ffffffeell, KEY_ESC },
291 		/* iMON Knob values */
292 		{ 0x000100ffffffffeell, KEY_VOLUMEUP },
293 		{ 0x010000ffffffffeell, KEY_VOLUMEDOWN },
294 		{ 0x000008ffffffffeell, KEY_MUTE },
295 		{ 0, KEY_RESERVED },
296 	}
297 };
298 
299 /* imon receiver front panel/knob key table for DH102*/
300 static const struct imon_usb_dev_descr imon_DH102 = {
301 	.flags = IMON_NO_FLAGS,
302 	.key_table = {
303 		{ 0x000100000000ffeell, KEY_VOLUMEUP },
304 		{ 0x010000000000ffeell, KEY_VOLUMEDOWN },
305 		{ 0x000000010000ffeell, KEY_MUTE },
306 		{ 0x0000000f0000ffeell, KEY_MEDIA },
307 		{ 0x000000120000ffeell, KEY_UP },
308 		{ 0x000000130000ffeell, KEY_DOWN },
309 		{ 0x000000140000ffeell, KEY_LEFT },
310 		{ 0x000000150000ffeell, KEY_RIGHT },
311 		{ 0x000000160000ffeell, KEY_ENTER },
312 		{ 0x000000170000ffeell, KEY_ESC },
313 		{ 0x0000002b0000ffeell, KEY_EXIT },
314 		{ 0x0000002c0000ffeell, KEY_SELECT },
315 		{ 0x0000002d0000ffeell, KEY_MENU },
316 		{ 0, KEY_RESERVED }
317 	}
318 };
319 
320 /* imon ultrabay front panel key table */
321 static const struct imon_usb_dev_descr ultrabay_table = {
322 	.flags = IMON_SUPPRESS_REPEATED_KEYS,
323 	.key_table = {
324 		{ 0x0000000f0000ffeell, KEY_MEDIA },      /* Go */
325 		{ 0x000000000100ffeell, KEY_UP },
326 		{ 0x000000000001ffeell, KEY_DOWN },
327 		{ 0x000000160000ffeell, KEY_ENTER },
328 		{ 0x0000001f0000ffeell, KEY_AUDIO },      /* Music */
329 		{ 0x000000200000ffeell, KEY_VIDEO },      /* Movie */
330 		{ 0x000000210000ffeell, KEY_CAMERA },     /* Photo */
331 		{ 0x000000270000ffeell, KEY_DVD },        /* DVD */
332 		{ 0x000000230000ffeell, KEY_TV },         /* TV */
333 		{ 0x000000050000ffeell, KEY_PREVIOUS },   /* Previous */
334 		{ 0x000000070000ffeell, KEY_REWIND },
335 		{ 0x000000040000ffeell, KEY_STOP },
336 		{ 0x000000020000ffeell, KEY_PLAYPAUSE },
337 		{ 0x000000080000ffeell, KEY_FASTFORWARD },
338 		{ 0x000000060000ffeell, KEY_NEXT },       /* Next */
339 		{ 0x000100000000ffeell, KEY_VOLUMEUP },
340 		{ 0x010000000000ffeell, KEY_VOLUMEDOWN },
341 		{ 0x000000010000ffeell, KEY_MUTE },
342 		{ 0, KEY_RESERVED },
343 	}
344 };
345 
346 /*
347  * USB Device ID for iMON USB Control Boards
348  *
349  * The Windows drivers contain 6 different inf files, more or less one for
350  * each new device until the 0x0034-0x0046 devices, which all use the same
351  * driver. Some of the devices in the 34-46 range haven't been definitively
352  * identified yet. Early devices have either a TriGem Computer, Inc. or a
353  * Samsung vendor ID (0x0aa8 and 0x04e8 respectively), while all later
354  * devices use the SoundGraph vendor ID (0x15c2). This driver only supports
355  * the ffdc and later devices, which do onboard decoding.
356  */
357 static const struct usb_device_id imon_usb_id_table[] = {
358 	/*
359 	 * Several devices with this same device ID, all use iMON_PAD.inf
360 	 * SoundGraph iMON PAD (IR & VFD)
361 	 * SoundGraph iMON PAD (IR & LCD)
362 	 * SoundGraph iMON Knob (IR only)
363 	 */
364 	{ USB_DEVICE(0x15c2, 0xffdc),
365 	  .driver_info = (unsigned long)&imon_default_table },
366 
367 	/*
368 	 * Newer devices, all driven by the latest iMON Windows driver, full
369 	 * list of device IDs extracted via 'strings Setup/data1.hdr |grep 15c2'
370 	 * Need user input to fill in details on unknown devices.
371 	 */
372 	/* SoundGraph iMON OEM Touch LCD (IR & 7" VGA LCD) */
373 	{ USB_DEVICE(0x15c2, 0x0034),
374 	  .driver_info = (unsigned long)&imon_DH102 },
375 	/* SoundGraph iMON OEM Touch LCD (IR & 4.3" VGA LCD) */
376 	{ USB_DEVICE(0x15c2, 0x0035),
377 	  .driver_info = (unsigned long)&imon_default_table},
378 	/* SoundGraph iMON OEM VFD (IR & VFD) */
379 	{ USB_DEVICE(0x15c2, 0x0036),
380 	  .driver_info = (unsigned long)&imon_OEM_VFD },
381 	/* device specifics unknown */
382 	{ USB_DEVICE(0x15c2, 0x0037),
383 	  .driver_info = (unsigned long)&imon_default_table},
384 	/* SoundGraph iMON OEM LCD (IR & LCD) */
385 	{ USB_DEVICE(0x15c2, 0x0038),
386 	  .driver_info = (unsigned long)&imon_default_table},
387 	/* SoundGraph iMON UltraBay (IR & LCD) */
388 	{ USB_DEVICE(0x15c2, 0x0039),
389 	  .driver_info = (unsigned long)&imon_default_table},
390 	/* device specifics unknown */
391 	{ USB_DEVICE(0x15c2, 0x003a),
392 	  .driver_info = (unsigned long)&imon_default_table},
393 	/* device specifics unknown */
394 	{ USB_DEVICE(0x15c2, 0x003b),
395 	  .driver_info = (unsigned long)&imon_default_table},
396 	/* SoundGraph iMON OEM Inside (IR only) */
397 	{ USB_DEVICE(0x15c2, 0x003c),
398 	  .driver_info = (unsigned long)&imon_default_table},
399 	/* device specifics unknown */
400 	{ USB_DEVICE(0x15c2, 0x003d),
401 	  .driver_info = (unsigned long)&imon_default_table},
402 	/* device specifics unknown */
403 	{ USB_DEVICE(0x15c2, 0x003e),
404 	  .driver_info = (unsigned long)&imon_default_table},
405 	/* device specifics unknown */
406 	{ USB_DEVICE(0x15c2, 0x003f),
407 	  .driver_info = (unsigned long)&imon_default_table},
408 	/* device specifics unknown */
409 	{ USB_DEVICE(0x15c2, 0x0040),
410 	  .driver_info = (unsigned long)&imon_default_table},
411 	/* SoundGraph iMON MINI (IR only) */
412 	{ USB_DEVICE(0x15c2, 0x0041),
413 	  .driver_info = (unsigned long)&imon_default_table},
414 	/* Antec Veris Multimedia Station EZ External (IR only) */
415 	{ USB_DEVICE(0x15c2, 0x0042),
416 	  .driver_info = (unsigned long)&imon_default_table},
417 	/* Antec Veris Multimedia Station Basic Internal (IR only) */
418 	{ USB_DEVICE(0x15c2, 0x0043),
419 	  .driver_info = (unsigned long)&imon_default_table},
420 	/* Antec Veris Multimedia Station Elite (IR & VFD) */
421 	{ USB_DEVICE(0x15c2, 0x0044),
422 	  .driver_info = (unsigned long)&imon_default_table},
423 	/* Antec Veris Multimedia Station Premiere (IR & LCD) */
424 	{ USB_DEVICE(0x15c2, 0x0045),
425 	  .driver_info = (unsigned long)&imon_default_table},
426 	/* device specifics unknown */
427 	{ USB_DEVICE(0x15c2, 0x0046),
428 	  .driver_info = (unsigned long)&imon_default_table},
429 	{}
430 };
431 
432 /* USB Device data */
433 static struct usb_driver imon_driver = {
434 	.name		= MOD_NAME,
435 	.probe		= imon_probe,
436 	.disconnect	= imon_disconnect,
437 	.suspend	= imon_suspend,
438 	.resume		= imon_resume,
439 	.id_table	= imon_usb_id_table,
440 };
441 
442 /* to prevent races between open() and disconnect(), probing, etc */
443 static DEFINE_MUTEX(driver_lock);
444 
445 /* Module bookkeeping bits */
446 MODULE_AUTHOR(MOD_AUTHOR);
447 MODULE_DESCRIPTION(MOD_DESC);
448 MODULE_VERSION(MOD_VERSION);
449 MODULE_LICENSE("GPL");
450 MODULE_DEVICE_TABLE(usb, imon_usb_id_table);
451 
452 static bool debug;
453 module_param(debug, bool, S_IRUGO | S_IWUSR);
454 MODULE_PARM_DESC(debug, "Debug messages: 0=no, 1=yes (default: no)");
455 
456 /* lcd, vfd, vga or none? should be auto-detected, but can be overridden... */
457 static int display_type;
458 module_param(display_type, int, S_IRUGO);
459 MODULE_PARM_DESC(display_type, "Type of attached display. 0=autodetect, 1=vfd, 2=lcd, 3=vga, 4=none (default: autodetect)");
460 
461 static int pad_stabilize = 1;
462 module_param(pad_stabilize, int, S_IRUGO | S_IWUSR);
463 MODULE_PARM_DESC(pad_stabilize, "Apply stabilization algorithm to iMON PAD presses in arrow key mode. 0=disable, 1=enable (default).");
464 
465 /*
466  * In certain use cases, mouse mode isn't really helpful, and could actually
467  * cause confusion, so allow disabling it when the IR device is open.
468  */
469 static bool nomouse;
470 module_param(nomouse, bool, S_IRUGO | S_IWUSR);
471 MODULE_PARM_DESC(nomouse, "Disable mouse input device mode when IR device is open. 0=don't disable, 1=disable. (default: don't disable)");
472 
473 /* threshold at which a pad push registers as an arrow key in kbd mode */
474 static int pad_thresh;
475 module_param(pad_thresh, int, S_IRUGO | S_IWUSR);
476 MODULE_PARM_DESC(pad_thresh, "Threshold at which a pad push registers as an arrow key in kbd mode (default: 28)");
477 
478 
479 static void free_imon_context(struct imon_context *ictx)
480 {
481 	struct device *dev = ictx->dev;
482 
483 	usb_free_urb(ictx->tx_urb);
484 	usb_free_urb(ictx->rx_urb_intf0);
485 	usb_free_urb(ictx->rx_urb_intf1);
486 	kfree(ictx);
487 
488 	dev_dbg(dev, "%s: iMON context freed\n", __func__);
489 }
490 
491 /*
492  * Called when the Display device (e.g. /dev/lcd0)
493  * is opened by the application.
494  */
495 static int display_open(struct inode *inode, struct file *file)
496 {
497 	struct usb_interface *interface;
498 	struct imon_context *ictx = NULL;
499 	int subminor;
500 	int retval = 0;
501 
502 	/* prevent races with disconnect */
503 	mutex_lock(&driver_lock);
504 
505 	subminor = iminor(inode);
506 	interface = usb_find_interface(&imon_driver, subminor);
507 	if (!interface) {
508 		pr_err("could not find interface for minor %d\n", subminor);
509 		retval = -ENODEV;
510 		goto exit;
511 	}
512 	ictx = usb_get_intfdata(interface);
513 
514 	if (!ictx) {
515 		pr_err("no context found for minor %d\n", subminor);
516 		retval = -ENODEV;
517 		goto exit;
518 	}
519 
520 	mutex_lock(&ictx->lock);
521 
522 	if (!ictx->display_supported) {
523 		pr_err("display not supported by device\n");
524 		retval = -ENODEV;
525 	} else if (ictx->display_isopen) {
526 		pr_err("display port is already open\n");
527 		retval = -EBUSY;
528 	} else {
529 		ictx->display_isopen = true;
530 		file->private_data = ictx;
531 		dev_dbg(ictx->dev, "display port opened\n");
532 	}
533 
534 	mutex_unlock(&ictx->lock);
535 
536 exit:
537 	mutex_unlock(&driver_lock);
538 	return retval;
539 }
540 
541 /*
542  * Called when the display device (e.g. /dev/lcd0)
543  * is closed by the application.
544  */
545 static int display_close(struct inode *inode, struct file *file)
546 {
547 	struct imon_context *ictx = NULL;
548 	int retval = 0;
549 
550 	ictx = file->private_data;
551 
552 	if (!ictx) {
553 		pr_err("no context for device\n");
554 		return -ENODEV;
555 	}
556 
557 	mutex_lock(&ictx->lock);
558 
559 	if (!ictx->display_supported) {
560 		pr_err("display not supported by device\n");
561 		retval = -ENODEV;
562 	} else if (!ictx->display_isopen) {
563 		pr_err("display is not open\n");
564 		retval = -EIO;
565 	} else {
566 		ictx->display_isopen = false;
567 		dev_dbg(ictx->dev, "display port closed\n");
568 	}
569 
570 	mutex_unlock(&ictx->lock);
571 	return retval;
572 }
573 
574 /*
575  * Sends a packet to the device -- this function must be called with
576  * ictx->lock held, or its unlock/lock sequence while waiting for tx
577  * to complete can/will lead to a deadlock.
578  */
579 static int send_packet(struct imon_context *ictx)
580 {
581 	unsigned int pipe;
582 	unsigned long timeout;
583 	int interval = 0;
584 	int retval = 0;
585 	struct usb_ctrlrequest *control_req = NULL;
586 
587 	/* Check if we need to use control or interrupt urb */
588 	if (!ictx->tx_control) {
589 		pipe = usb_sndintpipe(ictx->usbdev_intf0,
590 				      ictx->tx_endpoint->bEndpointAddress);
591 		interval = ictx->tx_endpoint->bInterval;
592 
593 		usb_fill_int_urb(ictx->tx_urb, ictx->usbdev_intf0, pipe,
594 				 ictx->usb_tx_buf,
595 				 sizeof(ictx->usb_tx_buf),
596 				 usb_tx_callback, ictx, interval);
597 
598 		ictx->tx_urb->actual_length = 0;
599 	} else {
600 		/* fill request into kmalloc'ed space: */
601 		control_req = kmalloc(sizeof(*control_req), GFP_KERNEL);
602 		if (control_req == NULL)
603 			return -ENOMEM;
604 
605 		/* setup packet is '21 09 0200 0001 0008' */
606 		control_req->bRequestType = 0x21;
607 		control_req->bRequest = 0x09;
608 		control_req->wValue = cpu_to_le16(0x0200);
609 		control_req->wIndex = cpu_to_le16(0x0001);
610 		control_req->wLength = cpu_to_le16(0x0008);
611 
612 		/* control pipe is endpoint 0x00 */
613 		pipe = usb_sndctrlpipe(ictx->usbdev_intf0, 0);
614 
615 		/* build the control urb */
616 		usb_fill_control_urb(ictx->tx_urb, ictx->usbdev_intf0,
617 				     pipe, (unsigned char *)control_req,
618 				     ictx->usb_tx_buf,
619 				     sizeof(ictx->usb_tx_buf),
620 				     usb_tx_callback, ictx);
621 		ictx->tx_urb->actual_length = 0;
622 	}
623 
624 	reinit_completion(&ictx->tx.finished);
625 	ictx->tx.busy = true;
626 	smp_rmb(); /* ensure later readers know we're busy */
627 
628 	retval = usb_submit_urb(ictx->tx_urb, GFP_KERNEL);
629 	if (retval) {
630 		ictx->tx.busy = false;
631 		smp_rmb(); /* ensure later readers know we're not busy */
632 		pr_err_ratelimited("error submitting urb(%d)\n", retval);
633 	} else {
634 		/* Wait for transmission to complete (or abort) */
635 		mutex_unlock(&ictx->lock);
636 		retval = wait_for_completion_interruptible(
637 				&ictx->tx.finished);
638 		if (retval) {
639 			usb_kill_urb(ictx->tx_urb);
640 			pr_err_ratelimited("task interrupted\n");
641 		}
642 		mutex_lock(&ictx->lock);
643 
644 		retval = ictx->tx.status;
645 		if (retval)
646 			pr_err_ratelimited("packet tx failed (%d)\n", retval);
647 	}
648 
649 	kfree(control_req);
650 
651 	/*
652 	 * Induce a mandatory delay before returning, as otherwise,
653 	 * send_packet can get called so rapidly as to overwhelm the device,
654 	 * particularly on faster systems and/or those with quirky usb.
655 	 */
656 	timeout = msecs_to_jiffies(ictx->send_packet_delay);
657 	set_current_state(TASK_INTERRUPTIBLE);
658 	schedule_timeout(timeout);
659 
660 	return retval;
661 }
662 
663 /*
664  * Sends an associate packet to the iMON 2.4G.
665  *
666  * This might not be such a good idea, since it has an id collision with
667  * some versions of the "IR & VFD" combo. The only way to determine if it
668  * is an RF version is to look at the product description string. (Which
669  * we currently do not fetch).
670  */
671 static int send_associate_24g(struct imon_context *ictx)
672 {
673 	int retval;
674 	const unsigned char packet[8] = { 0x01, 0x00, 0x00, 0x00,
675 					  0x00, 0x00, 0x00, 0x20 };
676 
677 	if (!ictx) {
678 		pr_err("no context for device\n");
679 		return -ENODEV;
680 	}
681 
682 	if (!ictx->dev_present_intf0) {
683 		pr_err("no iMON device present\n");
684 		return -ENODEV;
685 	}
686 
687 	memcpy(ictx->usb_tx_buf, packet, sizeof(packet));
688 	retval = send_packet(ictx);
689 
690 	return retval;
691 }
692 
693 /*
694  * Sends packets to setup and show clock on iMON display
695  *
696  * Arguments: year - last 2 digits of year, month - 1..12,
697  * day - 1..31, dow - day of the week (0-Sun...6-Sat),
698  * hour - 0..23, minute - 0..59, second - 0..59
699  */
700 static int send_set_imon_clock(struct imon_context *ictx,
701 			       unsigned int year, unsigned int month,
702 			       unsigned int day, unsigned int dow,
703 			       unsigned int hour, unsigned int minute,
704 			       unsigned int second)
705 {
706 	unsigned char clock_enable_pkt[IMON_CLOCK_ENABLE_PACKETS][8];
707 	int retval = 0;
708 	int i;
709 
710 	if (!ictx) {
711 		pr_err("no context for device\n");
712 		return -ENODEV;
713 	}
714 
715 	switch (ictx->display_type) {
716 	case IMON_DISPLAY_TYPE_LCD:
717 		clock_enable_pkt[0][0] = 0x80;
718 		clock_enable_pkt[0][1] = year;
719 		clock_enable_pkt[0][2] = month-1;
720 		clock_enable_pkt[0][3] = day;
721 		clock_enable_pkt[0][4] = hour;
722 		clock_enable_pkt[0][5] = minute;
723 		clock_enable_pkt[0][6] = second;
724 
725 		clock_enable_pkt[1][0] = 0x80;
726 		clock_enable_pkt[1][1] = 0;
727 		clock_enable_pkt[1][2] = 0;
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 
733 		if (ictx->product == 0xffdc) {
734 			clock_enable_pkt[0][7] = 0x50;
735 			clock_enable_pkt[1][7] = 0x51;
736 		} else {
737 			clock_enable_pkt[0][7] = 0x88;
738 			clock_enable_pkt[1][7] = 0x8a;
739 		}
740 
741 		break;
742 
743 	case IMON_DISPLAY_TYPE_VFD:
744 		clock_enable_pkt[0][0] = year;
745 		clock_enable_pkt[0][1] = month-1;
746 		clock_enable_pkt[0][2] = day;
747 		clock_enable_pkt[0][3] = dow;
748 		clock_enable_pkt[0][4] = hour;
749 		clock_enable_pkt[0][5] = minute;
750 		clock_enable_pkt[0][6] = second;
751 		clock_enable_pkt[0][7] = 0x40;
752 
753 		clock_enable_pkt[1][0] = 0;
754 		clock_enable_pkt[1][1] = 0;
755 		clock_enable_pkt[1][2] = 1;
756 		clock_enable_pkt[1][3] = 0;
757 		clock_enable_pkt[1][4] = 0;
758 		clock_enable_pkt[1][5] = 0;
759 		clock_enable_pkt[1][6] = 0;
760 		clock_enable_pkt[1][7] = 0x42;
761 
762 		break;
763 
764 	default:
765 		return -ENODEV;
766 	}
767 
768 	for (i = 0; i < IMON_CLOCK_ENABLE_PACKETS; i++) {
769 		memcpy(ictx->usb_tx_buf, clock_enable_pkt[i], 8);
770 		retval = send_packet(ictx);
771 		if (retval) {
772 			pr_err("send_packet failed for packet %d\n", i);
773 			break;
774 		}
775 	}
776 
777 	return retval;
778 }
779 
780 /*
781  * These are the sysfs functions to handle the association on the iMON 2.4G LT.
782  */
783 static ssize_t show_associate_remote(struct device *d,
784 				     struct device_attribute *attr,
785 				     char *buf)
786 {
787 	struct imon_context *ictx = dev_get_drvdata(d);
788 
789 	if (!ictx)
790 		return -ENODEV;
791 
792 	mutex_lock(&ictx->lock);
793 	if (ictx->rf_isassociating)
794 		strscpy(buf, "associating\n", PAGE_SIZE);
795 	else
796 		strscpy(buf, "closed\n", PAGE_SIZE);
797 
798 	dev_info(d, "Visit https://www.lirc.org/html/imon-24g.html for instructions on how to associate your iMON 2.4G DT/LT remote\n");
799 	mutex_unlock(&ictx->lock);
800 	return strlen(buf);
801 }
802 
803 static ssize_t store_associate_remote(struct device *d,
804 				      struct device_attribute *attr,
805 				      const char *buf, size_t count)
806 {
807 	struct imon_context *ictx;
808 
809 	ictx = dev_get_drvdata(d);
810 
811 	if (!ictx)
812 		return -ENODEV;
813 
814 	mutex_lock(&ictx->lock);
815 	ictx->rf_isassociating = true;
816 	send_associate_24g(ictx);
817 	mutex_unlock(&ictx->lock);
818 
819 	return count;
820 }
821 
822 /*
823  * sysfs functions to control internal imon clock
824  */
825 static ssize_t show_imon_clock(struct device *d,
826 			       struct device_attribute *attr, char *buf)
827 {
828 	struct imon_context *ictx = dev_get_drvdata(d);
829 	size_t len;
830 
831 	if (!ictx)
832 		return -ENODEV;
833 
834 	mutex_lock(&ictx->lock);
835 
836 	if (!ictx->display_supported) {
837 		len = snprintf(buf, PAGE_SIZE, "Not supported.");
838 	} else {
839 		len = snprintf(buf, PAGE_SIZE,
840 			"To set the clock on your iMON display:\n"
841 			"# date \"+%%y %%m %%d %%w %%H %%M %%S\" > imon_clock\n"
842 			"%s", ictx->display_isopen ?
843 			"\nNOTE: imon device must be closed\n" : "");
844 	}
845 
846 	mutex_unlock(&ictx->lock);
847 
848 	return len;
849 }
850 
851 static ssize_t store_imon_clock(struct device *d,
852 				struct device_attribute *attr,
853 				const char *buf, size_t count)
854 {
855 	struct imon_context *ictx = dev_get_drvdata(d);
856 	ssize_t retval;
857 	unsigned int year, month, day, dow, hour, minute, second;
858 
859 	if (!ictx)
860 		return -ENODEV;
861 
862 	mutex_lock(&ictx->lock);
863 
864 	if (!ictx->display_supported) {
865 		retval = -ENODEV;
866 		goto exit;
867 	} else if (ictx->display_isopen) {
868 		retval = -EBUSY;
869 		goto exit;
870 	}
871 
872 	if (sscanf(buf, "%u %u %u %u %u %u %u",	&year, &month, &day, &dow,
873 		   &hour, &minute, &second) != 7) {
874 		retval = -EINVAL;
875 		goto exit;
876 	}
877 
878 	if ((month < 1 || month > 12) ||
879 	    (day < 1 || day > 31) || (dow > 6) ||
880 	    (hour > 23) || (minute > 59) || (second > 59)) {
881 		retval = -EINVAL;
882 		goto exit;
883 	}
884 
885 	retval = send_set_imon_clock(ictx, year, month, day, dow,
886 				     hour, minute, second);
887 	if (retval)
888 		goto exit;
889 
890 	retval = count;
891 exit:
892 	mutex_unlock(&ictx->lock);
893 
894 	return retval;
895 }
896 
897 
898 static DEVICE_ATTR(imon_clock, S_IWUSR | S_IRUGO, show_imon_clock,
899 		   store_imon_clock);
900 
901 static DEVICE_ATTR(associate_remote, S_IWUSR | S_IRUGO, show_associate_remote,
902 		   store_associate_remote);
903 
904 static struct attribute *imon_display_sysfs_entries[] = {
905 	&dev_attr_imon_clock.attr,
906 	NULL
907 };
908 
909 static const struct attribute_group imon_display_attr_group = {
910 	.attrs = imon_display_sysfs_entries
911 };
912 
913 static struct attribute *imon_rf_sysfs_entries[] = {
914 	&dev_attr_associate_remote.attr,
915 	NULL
916 };
917 
918 static const struct attribute_group imon_rf_attr_group = {
919 	.attrs = imon_rf_sysfs_entries
920 };
921 
922 /*
923  * Writes data to the VFD.  The iMON VFD is 2x16 characters
924  * and requires data in 5 consecutive USB interrupt packets,
925  * each packet but the last carrying 7 bytes.
926  *
927  * I don't know if the VFD board supports features such as
928  * scrolling, clearing rows, blanking, etc. so at
929  * the caller must provide a full screen of data.  If fewer
930  * than 32 bytes are provided spaces will be appended to
931  * generate a full screen.
932  */
933 static ssize_t vfd_write(struct file *file, const char __user *buf,
934 			 size_t n_bytes, loff_t *pos)
935 {
936 	int i;
937 	int offset;
938 	int seq;
939 	int retval = 0;
940 	struct imon_context *ictx;
941 	static const unsigned char vfd_packet6[] = {
942 		0x01, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF };
943 
944 	ictx = file->private_data;
945 	if (!ictx) {
946 		pr_err_ratelimited("no context for device\n");
947 		return -ENODEV;
948 	}
949 
950 	mutex_lock(&ictx->lock);
951 
952 	if (!ictx->dev_present_intf0) {
953 		pr_err_ratelimited("no iMON device present\n");
954 		retval = -ENODEV;
955 		goto exit;
956 	}
957 
958 	if (n_bytes <= 0 || n_bytes > 32) {
959 		pr_err_ratelimited("invalid payload size\n");
960 		retval = -EINVAL;
961 		goto exit;
962 	}
963 
964 	if (copy_from_user(ictx->tx.data_buf, buf, n_bytes)) {
965 		retval = -EFAULT;
966 		goto exit;
967 	}
968 
969 	/* Pad with spaces */
970 	for (i = n_bytes; i < 32; ++i)
971 		ictx->tx.data_buf[i] = ' ';
972 
973 	for (i = 32; i < 35; ++i)
974 		ictx->tx.data_buf[i] = 0xFF;
975 
976 	offset = 0;
977 	seq = 0;
978 
979 	do {
980 		memcpy(ictx->usb_tx_buf, ictx->tx.data_buf + offset, 7);
981 		ictx->usb_tx_buf[7] = (unsigned char) seq;
982 
983 		retval = send_packet(ictx);
984 		if (retval) {
985 			pr_err_ratelimited("send packet #%d failed\n", seq / 2);
986 			goto exit;
987 		} else {
988 			seq += 2;
989 			offset += 7;
990 		}
991 
992 	} while (offset < 35);
993 
994 	/* Send packet #6 */
995 	memcpy(ictx->usb_tx_buf, &vfd_packet6, sizeof(vfd_packet6));
996 	ictx->usb_tx_buf[7] = (unsigned char) seq;
997 	retval = send_packet(ictx);
998 	if (retval)
999 		pr_err_ratelimited("send packet #%d failed\n", seq / 2);
1000 
1001 exit:
1002 	mutex_unlock(&ictx->lock);
1003 
1004 	return (!retval) ? n_bytes : retval;
1005 }
1006 
1007 /*
1008  * Writes data to the LCD.  The iMON OEM LCD screen expects 8-byte
1009  * packets. We accept data as 16 hexadecimal digits, followed by a
1010  * newline (to make it easy to drive the device from a command-line
1011  * -- even though the actual binary data is a bit complicated).
1012  *
1013  * The device itself is not a "traditional" text-mode display. It's
1014  * actually a 16x96 pixel bitmap display. That means if you want to
1015  * display text, you've got to have your own "font" and translate the
1016  * text into bitmaps for display. This is really flexible (you can
1017  * display whatever diacritics you need, and so on), but it's also
1018  * a lot more complicated than most LCDs...
1019  */
1020 static ssize_t lcd_write(struct file *file, const char __user *buf,
1021 			 size_t n_bytes, loff_t *pos)
1022 {
1023 	int retval = 0;
1024 	struct imon_context *ictx;
1025 
1026 	ictx = file->private_data;
1027 	if (!ictx) {
1028 		pr_err_ratelimited("no context for device\n");
1029 		return -ENODEV;
1030 	}
1031 
1032 	mutex_lock(&ictx->lock);
1033 
1034 	if (!ictx->display_supported) {
1035 		pr_err_ratelimited("no iMON display present\n");
1036 		retval = -ENODEV;
1037 		goto exit;
1038 	}
1039 
1040 	if (n_bytes != 8) {
1041 		pr_err_ratelimited("invalid payload size: %d (expected 8)\n",
1042 				   (int)n_bytes);
1043 		retval = -EINVAL;
1044 		goto exit;
1045 	}
1046 
1047 	if (copy_from_user(ictx->usb_tx_buf, buf, 8)) {
1048 		retval = -EFAULT;
1049 		goto exit;
1050 	}
1051 
1052 	retval = send_packet(ictx);
1053 	if (retval) {
1054 		pr_err_ratelimited("send packet failed!\n");
1055 		goto exit;
1056 	} else {
1057 		dev_dbg(ictx->dev, "%s: write %d bytes to LCD\n",
1058 			__func__, (int) n_bytes);
1059 	}
1060 exit:
1061 	mutex_unlock(&ictx->lock);
1062 	return (!retval) ? n_bytes : retval;
1063 }
1064 
1065 /*
1066  * Callback function for USB core API: transmit data
1067  */
1068 static void usb_tx_callback(struct urb *urb)
1069 {
1070 	struct imon_context *ictx;
1071 
1072 	if (!urb)
1073 		return;
1074 	ictx = (struct imon_context *)urb->context;
1075 	if (!ictx)
1076 		return;
1077 
1078 	ictx->tx.status = urb->status;
1079 
1080 	/* notify waiters that write has finished */
1081 	ictx->tx.busy = false;
1082 	smp_rmb(); /* ensure later readers know we're not busy */
1083 	complete(&ictx->tx.finished);
1084 }
1085 
1086 /*
1087  * report touchscreen input
1088  */
1089 static void imon_touch_display_timeout(struct timer_list *t)
1090 {
1091 	struct imon_context *ictx = from_timer(ictx, t, ttimer);
1092 
1093 	if (ictx->display_type != IMON_DISPLAY_TYPE_VGA)
1094 		return;
1095 
1096 	input_report_abs(ictx->touch, ABS_X, ictx->touch_x);
1097 	input_report_abs(ictx->touch, ABS_Y, ictx->touch_y);
1098 	input_report_key(ictx->touch, BTN_TOUCH, 0x00);
1099 	input_sync(ictx->touch);
1100 }
1101 
1102 /*
1103  * iMON IR receivers support two different signal sets -- those used by
1104  * the iMON remotes, and those used by the Windows MCE remotes (which is
1105  * really just RC-6), but only one or the other at a time, as the signals
1106  * are decoded onboard the receiver.
1107  *
1108  * This function gets called two different ways, one way is from
1109  * rc_register_device, for initial protocol selection/setup, and the other is
1110  * via a userspace-initiated protocol change request, either by direct sysfs
1111  * prodding or by something like ir-keytable. In the rc_register_device case,
1112  * the imon context lock is already held, but when initiated from userspace,
1113  * it is not, so we must acquire it prior to calling send_packet, which
1114  * requires that the lock is held.
1115  */
1116 static int imon_ir_change_protocol(struct rc_dev *rc, u64 *rc_proto)
1117 {
1118 	int retval;
1119 	struct imon_context *ictx = rc->priv;
1120 	struct device *dev = ictx->dev;
1121 	bool unlock = false;
1122 	unsigned char ir_proto_packet[] = {
1123 		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x86 };
1124 
1125 	if (*rc_proto && !(*rc_proto & rc->allowed_protocols))
1126 		dev_warn(dev, "Looks like you're trying to use an IR protocol this device does not support\n");
1127 
1128 	if (*rc_proto & RC_PROTO_BIT_RC6_MCE) {
1129 		dev_dbg(dev, "Configuring IR receiver for MCE protocol\n");
1130 		ir_proto_packet[0] = 0x01;
1131 		*rc_proto = RC_PROTO_BIT_RC6_MCE;
1132 	} else if (*rc_proto & RC_PROTO_BIT_IMON) {
1133 		dev_dbg(dev, "Configuring IR receiver for iMON protocol\n");
1134 		if (!pad_stabilize)
1135 			dev_dbg(dev, "PAD stabilize functionality disabled\n");
1136 		/* ir_proto_packet[0] = 0x00; // already the default */
1137 		*rc_proto = RC_PROTO_BIT_IMON;
1138 	} else {
1139 		dev_warn(dev, "Unsupported IR protocol specified, overriding to iMON IR protocol\n");
1140 		if (!pad_stabilize)
1141 			dev_dbg(dev, "PAD stabilize functionality disabled\n");
1142 		/* ir_proto_packet[0] = 0x00; // already the default */
1143 		*rc_proto = RC_PROTO_BIT_IMON;
1144 	}
1145 
1146 	memcpy(ictx->usb_tx_buf, &ir_proto_packet, sizeof(ir_proto_packet));
1147 
1148 	if (!mutex_is_locked(&ictx->lock)) {
1149 		unlock = true;
1150 		mutex_lock(&ictx->lock);
1151 	}
1152 
1153 	retval = send_packet(ictx);
1154 	if (retval)
1155 		goto out;
1156 
1157 	ictx->rc_proto = *rc_proto;
1158 	ictx->pad_mouse = false;
1159 
1160 out:
1161 	if (unlock)
1162 		mutex_unlock(&ictx->lock);
1163 
1164 	return retval;
1165 }
1166 
1167 /*
1168  * The directional pad behaves a bit differently, depending on whether this is
1169  * one of the older ffdc devices or a newer device. Newer devices appear to
1170  * have a higher resolution matrix for more precise mouse movement, but it
1171  * makes things overly sensitive in keyboard mode, so we do some interesting
1172  * contortions to make it less touchy. Older devices run through the same
1173  * routine with shorter timeout and a smaller threshold.
1174  */
1175 static int stabilize(int a, int b, u16 timeout, u16 threshold)
1176 {
1177 	ktime_t ct;
1178 	static ktime_t prev_time;
1179 	static ktime_t hit_time;
1180 	static int x, y, prev_result, hits;
1181 	int result = 0;
1182 	long msec, msec_hit;
1183 
1184 	ct = ktime_get();
1185 	msec = ktime_ms_delta(ct, prev_time);
1186 	msec_hit = ktime_ms_delta(ct, hit_time);
1187 
1188 	if (msec > 100) {
1189 		x = 0;
1190 		y = 0;
1191 		hits = 0;
1192 	}
1193 
1194 	x += a;
1195 	y += b;
1196 
1197 	prev_time = ct;
1198 
1199 	if (abs(x) > threshold || abs(y) > threshold) {
1200 		if (abs(y) > abs(x))
1201 			result = (y > 0) ? 0x7F : 0x80;
1202 		else
1203 			result = (x > 0) ? 0x7F00 : 0x8000;
1204 
1205 		x = 0;
1206 		y = 0;
1207 
1208 		if (result == prev_result) {
1209 			hits++;
1210 
1211 			if (hits > 3) {
1212 				switch (result) {
1213 				case 0x7F:
1214 					y = 17 * threshold / 30;
1215 					break;
1216 				case 0x80:
1217 					y -= 17 * threshold / 30;
1218 					break;
1219 				case 0x7F00:
1220 					x = 17 * threshold / 30;
1221 					break;
1222 				case 0x8000:
1223 					x -= 17 * threshold / 30;
1224 					break;
1225 				}
1226 			}
1227 
1228 			if (hits == 2 && msec_hit < timeout) {
1229 				result = 0;
1230 				hits = 1;
1231 			}
1232 		} else {
1233 			prev_result = result;
1234 			hits = 1;
1235 			hit_time = ct;
1236 		}
1237 	}
1238 
1239 	return result;
1240 }
1241 
1242 static u32 imon_remote_key_lookup(struct imon_context *ictx, u32 scancode)
1243 {
1244 	u32 keycode;
1245 	u32 release;
1246 	bool is_release_code = false;
1247 
1248 	/* Look for the initial press of a button */
1249 	keycode = rc_g_keycode_from_table(ictx->rdev, scancode);
1250 	ictx->rc_toggle = 0x0;
1251 	ictx->rc_scancode = scancode;
1252 
1253 	/* Look for the release of a button */
1254 	if (keycode == KEY_RESERVED) {
1255 		release = scancode & ~0x4000;
1256 		keycode = rc_g_keycode_from_table(ictx->rdev, release);
1257 		if (keycode != KEY_RESERVED)
1258 			is_release_code = true;
1259 	}
1260 
1261 	ictx->release_code = is_release_code;
1262 
1263 	return keycode;
1264 }
1265 
1266 static u32 imon_mce_key_lookup(struct imon_context *ictx, u32 scancode)
1267 {
1268 	u32 keycode;
1269 
1270 #define MCE_KEY_MASK 0x7000
1271 #define MCE_TOGGLE_BIT 0x8000
1272 
1273 	/*
1274 	 * On some receivers, mce keys decode to 0x8000f04xx and 0x8000f84xx
1275 	 * (the toggle bit flipping between alternating key presses), while
1276 	 * on other receivers, we see 0x8000f74xx and 0x8000ff4xx. To keep
1277 	 * the table trim, we always or in the bits to look up 0x8000ff4xx,
1278 	 * but we can't or them into all codes, as some keys are decoded in
1279 	 * a different way w/o the same use of the toggle bit...
1280 	 */
1281 	if (scancode & 0x80000000)
1282 		scancode = scancode | MCE_KEY_MASK | MCE_TOGGLE_BIT;
1283 
1284 	ictx->rc_scancode = scancode;
1285 	keycode = rc_g_keycode_from_table(ictx->rdev, scancode);
1286 
1287 	/* not used in mce mode, but make sure we know its false */
1288 	ictx->release_code = false;
1289 
1290 	return keycode;
1291 }
1292 
1293 static u32 imon_panel_key_lookup(struct imon_context *ictx, u64 code)
1294 {
1295 	const struct imon_panel_key_table *key_table;
1296 	u32 keycode = KEY_RESERVED;
1297 	int i;
1298 
1299 	key_table = ictx->dev_descr->key_table;
1300 
1301 	for (i = 0; key_table[i].hw_code != 0; i++) {
1302 		if (key_table[i].hw_code == (code | 0xffee)) {
1303 			keycode = key_table[i].keycode;
1304 			break;
1305 		}
1306 	}
1307 	ictx->release_code = false;
1308 	return keycode;
1309 }
1310 
1311 static bool imon_mouse_event(struct imon_context *ictx,
1312 			     unsigned char *buf, int len)
1313 {
1314 	signed char rel_x = 0x00, rel_y = 0x00;
1315 	u8 right_shift = 1;
1316 	bool mouse_input = true;
1317 	int dir = 0;
1318 	unsigned long flags;
1319 
1320 	spin_lock_irqsave(&ictx->kc_lock, flags);
1321 
1322 	/* newer iMON device PAD or mouse button */
1323 	if (ictx->product != 0xffdc && (buf[0] & 0x01) && len == 5) {
1324 		rel_x = buf[2];
1325 		rel_y = buf[3];
1326 		right_shift = 1;
1327 	/* 0xffdc iMON PAD or mouse button input */
1328 	} else if (ictx->product == 0xffdc && (buf[0] & 0x40) &&
1329 			!((buf[1] & 0x01) || ((buf[1] >> 2) & 0x01))) {
1330 		rel_x = (buf[1] & 0x08) | (buf[1] & 0x10) >> 2 |
1331 			(buf[1] & 0x20) >> 4 | (buf[1] & 0x40) >> 6;
1332 		if (buf[0] & 0x02)
1333 			rel_x |= ~0x0f;
1334 		rel_x = rel_x + rel_x / 2;
1335 		rel_y = (buf[2] & 0x08) | (buf[2] & 0x10) >> 2 |
1336 			(buf[2] & 0x20) >> 4 | (buf[2] & 0x40) >> 6;
1337 		if (buf[0] & 0x01)
1338 			rel_y |= ~0x0f;
1339 		rel_y = rel_y + rel_y / 2;
1340 		right_shift = 2;
1341 	/* some ffdc devices decode mouse buttons differently... */
1342 	} else if (ictx->product == 0xffdc && (buf[0] == 0x68)) {
1343 		right_shift = 2;
1344 	/* ch+/- buttons, which we use for an emulated scroll wheel */
1345 	} else if (ictx->kc == KEY_CHANNELUP && (buf[2] & 0x40) != 0x40) {
1346 		dir = 1;
1347 	} else if (ictx->kc == KEY_CHANNELDOWN && (buf[2] & 0x40) != 0x40) {
1348 		dir = -1;
1349 	} else
1350 		mouse_input = false;
1351 
1352 	spin_unlock_irqrestore(&ictx->kc_lock, flags);
1353 
1354 	if (mouse_input) {
1355 		dev_dbg(ictx->dev, "sending mouse data via input subsystem\n");
1356 
1357 		if (dir) {
1358 			input_report_rel(ictx->idev, REL_WHEEL, dir);
1359 		} else if (rel_x || rel_y) {
1360 			input_report_rel(ictx->idev, REL_X, rel_x);
1361 			input_report_rel(ictx->idev, REL_Y, rel_y);
1362 		} else {
1363 			input_report_key(ictx->idev, BTN_LEFT, buf[1] & 0x1);
1364 			input_report_key(ictx->idev, BTN_RIGHT,
1365 					 buf[1] >> right_shift & 0x1);
1366 		}
1367 		input_sync(ictx->idev);
1368 		spin_lock_irqsave(&ictx->kc_lock, flags);
1369 		ictx->last_keycode = ictx->kc;
1370 		spin_unlock_irqrestore(&ictx->kc_lock, flags);
1371 	}
1372 
1373 	return mouse_input;
1374 }
1375 
1376 static void imon_touch_event(struct imon_context *ictx, unsigned char *buf)
1377 {
1378 	mod_timer(&ictx->ttimer, jiffies + TOUCH_TIMEOUT);
1379 	ictx->touch_x = (buf[0] << 4) | (buf[1] >> 4);
1380 	ictx->touch_y = 0xfff - ((buf[2] << 4) | (buf[1] & 0xf));
1381 	input_report_abs(ictx->touch, ABS_X, ictx->touch_x);
1382 	input_report_abs(ictx->touch, ABS_Y, ictx->touch_y);
1383 	input_report_key(ictx->touch, BTN_TOUCH, 0x01);
1384 	input_sync(ictx->touch);
1385 }
1386 
1387 static void imon_pad_to_keys(struct imon_context *ictx, unsigned char *buf)
1388 {
1389 	int dir = 0;
1390 	signed char rel_x = 0x00, rel_y = 0x00;
1391 	u16 timeout, threshold;
1392 	u32 scancode = KEY_RESERVED;
1393 	unsigned long flags;
1394 
1395 	/*
1396 	 * The imon directional pad functions more like a touchpad. Bytes 3 & 4
1397 	 * contain a position coordinate (x,y), with each component ranging
1398 	 * from -14 to 14. We want to down-sample this to only 4 discrete values
1399 	 * for up/down/left/right arrow keys. Also, when you get too close to
1400 	 * diagonals, it has a tendency to jump back and forth, so lets try to
1401 	 * ignore when they get too close.
1402 	 */
1403 	if (ictx->product != 0xffdc) {
1404 		/* first, pad to 8 bytes so it conforms with everything else */
1405 		buf[5] = buf[6] = buf[7] = 0;
1406 		timeout = 500;	/* in msecs */
1407 		/* (2*threshold) x (2*threshold) square */
1408 		threshold = pad_thresh ? pad_thresh : 28;
1409 		rel_x = buf[2];
1410 		rel_y = buf[3];
1411 
1412 		if (ictx->rc_proto == RC_PROTO_BIT_IMON && pad_stabilize) {
1413 			if ((buf[1] == 0) && ((rel_x != 0) || (rel_y != 0))) {
1414 				dir = stabilize((int)rel_x, (int)rel_y,
1415 						timeout, threshold);
1416 				if (!dir) {
1417 					spin_lock_irqsave(&ictx->kc_lock,
1418 							  flags);
1419 					ictx->kc = KEY_UNKNOWN;
1420 					spin_unlock_irqrestore(&ictx->kc_lock,
1421 							       flags);
1422 					return;
1423 				}
1424 				buf[2] = dir & 0xFF;
1425 				buf[3] = (dir >> 8) & 0xFF;
1426 				scancode = be32_to_cpu(*((__be32 *)buf));
1427 			}
1428 		} else {
1429 			/*
1430 			 * Hack alert: instead of using keycodes, we have
1431 			 * to use hard-coded scancodes here...
1432 			 */
1433 			if (abs(rel_y) > abs(rel_x)) {
1434 				buf[2] = (rel_y > 0) ? 0x7F : 0x80;
1435 				buf[3] = 0;
1436 				if (rel_y > 0)
1437 					scancode = 0x01007f00; /* KEY_DOWN */
1438 				else
1439 					scancode = 0x01008000; /* KEY_UP */
1440 			} else {
1441 				buf[2] = 0;
1442 				buf[3] = (rel_x > 0) ? 0x7F : 0x80;
1443 				if (rel_x > 0)
1444 					scancode = 0x0100007f; /* KEY_RIGHT */
1445 				else
1446 					scancode = 0x01000080; /* KEY_LEFT */
1447 			}
1448 		}
1449 
1450 	/*
1451 	 * Handle on-board decoded pad events for e.g. older VFD/iMON-Pad
1452 	 * device (15c2:ffdc). The remote generates various codes from
1453 	 * 0x68nnnnB7 to 0x6AnnnnB7, the left mouse button generates
1454 	 * 0x688301b7 and the right one 0x688481b7. All other keys generate
1455 	 * 0x2nnnnnnn. Position coordinate is encoded in buf[1] and buf[2] with
1456 	 * reversed endianness. Extract direction from buffer, rotate endianness,
1457 	 * adjust sign and feed the values into stabilize(). The resulting codes
1458 	 * will be 0x01008000, 0x01007F00, which match the newer devices.
1459 	 */
1460 	} else {
1461 		timeout = 10;	/* in msecs */
1462 		/* (2*threshold) x (2*threshold) square */
1463 		threshold = pad_thresh ? pad_thresh : 15;
1464 
1465 		/* buf[1] is x */
1466 		rel_x = (buf[1] & 0x08) | (buf[1] & 0x10) >> 2 |
1467 			(buf[1] & 0x20) >> 4 | (buf[1] & 0x40) >> 6;
1468 		if (buf[0] & 0x02)
1469 			rel_x |= ~0x10+1;
1470 		/* buf[2] is y */
1471 		rel_y = (buf[2] & 0x08) | (buf[2] & 0x10) >> 2 |
1472 			(buf[2] & 0x20) >> 4 | (buf[2] & 0x40) >> 6;
1473 		if (buf[0] & 0x01)
1474 			rel_y |= ~0x10+1;
1475 
1476 		buf[0] = 0x01;
1477 		buf[1] = buf[4] = buf[5] = buf[6] = buf[7] = 0;
1478 
1479 		if (ictx->rc_proto == RC_PROTO_BIT_IMON && pad_stabilize) {
1480 			dir = stabilize((int)rel_x, (int)rel_y,
1481 					timeout, threshold);
1482 			if (!dir) {
1483 				spin_lock_irqsave(&ictx->kc_lock, flags);
1484 				ictx->kc = KEY_UNKNOWN;
1485 				spin_unlock_irqrestore(&ictx->kc_lock, flags);
1486 				return;
1487 			}
1488 			buf[2] = dir & 0xFF;
1489 			buf[3] = (dir >> 8) & 0xFF;
1490 			scancode = be32_to_cpu(*((__be32 *)buf));
1491 		} else {
1492 			/*
1493 			 * Hack alert: instead of using keycodes, we have
1494 			 * to use hard-coded scancodes here...
1495 			 */
1496 			if (abs(rel_y) > abs(rel_x)) {
1497 				buf[2] = (rel_y > 0) ? 0x7F : 0x80;
1498 				buf[3] = 0;
1499 				if (rel_y > 0)
1500 					scancode = 0x01007f00; /* KEY_DOWN */
1501 				else
1502 					scancode = 0x01008000; /* KEY_UP */
1503 			} else {
1504 				buf[2] = 0;
1505 				buf[3] = (rel_x > 0) ? 0x7F : 0x80;
1506 				if (rel_x > 0)
1507 					scancode = 0x0100007f; /* KEY_RIGHT */
1508 				else
1509 					scancode = 0x01000080; /* KEY_LEFT */
1510 			}
1511 		}
1512 	}
1513 
1514 	if (scancode) {
1515 		spin_lock_irqsave(&ictx->kc_lock, flags);
1516 		ictx->kc = imon_remote_key_lookup(ictx, scancode);
1517 		spin_unlock_irqrestore(&ictx->kc_lock, flags);
1518 	}
1519 }
1520 
1521 /*
1522  * figure out if these is a press or a release. We don't actually
1523  * care about repeats, as those will be auto-generated within the IR
1524  * subsystem for repeating scancodes.
1525  */
1526 static int imon_parse_press_type(struct imon_context *ictx,
1527 				 unsigned char *buf, u8 ktype)
1528 {
1529 	int press_type = 0;
1530 	unsigned long flags;
1531 
1532 	spin_lock_irqsave(&ictx->kc_lock, flags);
1533 
1534 	/* key release of 0x02XXXXXX key */
1535 	if (ictx->kc == KEY_RESERVED && buf[0] == 0x02 && buf[3] == 0x00)
1536 		ictx->kc = ictx->last_keycode;
1537 
1538 	/* mouse button release on (some) 0xffdc devices */
1539 	else if (ictx->kc == KEY_RESERVED && buf[0] == 0x68 && buf[1] == 0x82 &&
1540 		 buf[2] == 0x81 && buf[3] == 0xb7)
1541 		ictx->kc = ictx->last_keycode;
1542 
1543 	/* mouse button release on (some other) 0xffdc devices */
1544 	else if (ictx->kc == KEY_RESERVED && buf[0] == 0x01 && buf[1] == 0x00 &&
1545 		 buf[2] == 0x81 && buf[3] == 0xb7)
1546 		ictx->kc = ictx->last_keycode;
1547 
1548 	/* mce-specific button handling, no keyup events */
1549 	else if (ktype == IMON_KEY_MCE) {
1550 		ictx->rc_toggle = buf[2];
1551 		press_type = 1;
1552 
1553 	/* incoherent or irrelevant data */
1554 	} else if (ictx->kc == KEY_RESERVED)
1555 		press_type = -EINVAL;
1556 
1557 	/* key release of 0xXXXXXXb7 key */
1558 	else if (ictx->release_code)
1559 		press_type = 0;
1560 
1561 	/* this is a button press */
1562 	else
1563 		press_type = 1;
1564 
1565 	spin_unlock_irqrestore(&ictx->kc_lock, flags);
1566 
1567 	return press_type;
1568 }
1569 
1570 /*
1571  * Process the incoming packet
1572  */
1573 static void imon_incoming_packet(struct imon_context *ictx,
1574 				 struct urb *urb, int intf)
1575 {
1576 	int len = urb->actual_length;
1577 	unsigned char *buf = urb->transfer_buffer;
1578 	struct device *dev = ictx->dev;
1579 	unsigned long flags;
1580 	u32 kc;
1581 	u64 scancode;
1582 	int press_type = 0;
1583 	ktime_t t;
1584 	static ktime_t prev_time;
1585 	u8 ktype;
1586 
1587 	/* filter out junk data on the older 0xffdc imon devices */
1588 	if ((buf[0] == 0xff) && (buf[1] == 0xff) && (buf[2] == 0xff))
1589 		return;
1590 
1591 	/* Figure out what key was pressed */
1592 	if (len == 8 && buf[7] == 0xee) {
1593 		scancode = be64_to_cpu(*((__be64 *)buf));
1594 		ktype = IMON_KEY_PANEL;
1595 		kc = imon_panel_key_lookup(ictx, scancode);
1596 		ictx->release_code = false;
1597 	} else {
1598 		scancode = be32_to_cpu(*((__be32 *)buf));
1599 		if (ictx->rc_proto == RC_PROTO_BIT_RC6_MCE) {
1600 			ktype = IMON_KEY_IMON;
1601 			if (buf[0] == 0x80)
1602 				ktype = IMON_KEY_MCE;
1603 			kc = imon_mce_key_lookup(ictx, scancode);
1604 		} else {
1605 			ktype = IMON_KEY_IMON;
1606 			kc = imon_remote_key_lookup(ictx, scancode);
1607 		}
1608 	}
1609 
1610 	spin_lock_irqsave(&ictx->kc_lock, flags);
1611 	/* keyboard/mouse mode toggle button */
1612 	if (kc == KEY_KEYBOARD && !ictx->release_code) {
1613 		ictx->last_keycode = kc;
1614 		if (!nomouse) {
1615 			ictx->pad_mouse = !ictx->pad_mouse;
1616 			dev_dbg(dev, "toggling to %s mode\n",
1617 				ictx->pad_mouse ? "mouse" : "keyboard");
1618 			spin_unlock_irqrestore(&ictx->kc_lock, flags);
1619 			return;
1620 		} else {
1621 			ictx->pad_mouse = false;
1622 			dev_dbg(dev, "mouse mode disabled, passing key value\n");
1623 		}
1624 	}
1625 
1626 	ictx->kc = kc;
1627 	spin_unlock_irqrestore(&ictx->kc_lock, flags);
1628 
1629 	/* send touchscreen events through input subsystem if touchpad data */
1630 	if (ictx->touch && len == 8 && buf[7] == 0x86) {
1631 		imon_touch_event(ictx, buf);
1632 		return;
1633 
1634 	/* look for mouse events with pad in mouse mode */
1635 	} else if (ictx->pad_mouse) {
1636 		if (imon_mouse_event(ictx, buf, len))
1637 			return;
1638 	}
1639 
1640 	/* Now for some special handling to convert pad input to arrow keys */
1641 	if (((len == 5) && (buf[0] == 0x01) && (buf[4] == 0x00)) ||
1642 	    ((len == 8) && (buf[0] & 0x40) &&
1643 	     !(buf[1] & 0x1 || buf[1] >> 2 & 0x1))) {
1644 		len = 8;
1645 		imon_pad_to_keys(ictx, buf);
1646 	}
1647 
1648 	if (debug) {
1649 		printk(KERN_INFO "intf%d decoded packet: %*ph\n",
1650 		       intf, len, buf);
1651 	}
1652 
1653 	press_type = imon_parse_press_type(ictx, buf, ktype);
1654 	if (press_type < 0)
1655 		goto not_input_data;
1656 
1657 	if (ktype != IMON_KEY_PANEL) {
1658 		if (press_type == 0)
1659 			rc_keyup(ictx->rdev);
1660 		else {
1661 			enum rc_proto proto;
1662 
1663 			if (ictx->rc_proto == RC_PROTO_BIT_RC6_MCE)
1664 				proto = RC_PROTO_RC6_MCE;
1665 			else if (ictx->rc_proto == RC_PROTO_BIT_IMON)
1666 				proto = RC_PROTO_IMON;
1667 			else
1668 				return;
1669 
1670 			rc_keydown(ictx->rdev, proto, ictx->rc_scancode,
1671 				   ictx->rc_toggle);
1672 
1673 			spin_lock_irqsave(&ictx->kc_lock, flags);
1674 			ictx->last_keycode = ictx->kc;
1675 			spin_unlock_irqrestore(&ictx->kc_lock, flags);
1676 		}
1677 		return;
1678 	}
1679 
1680 	/* Only panel type events left to process now */
1681 	spin_lock_irqsave(&ictx->kc_lock, flags);
1682 
1683 	t = ktime_get();
1684 	/* KEY repeats from knob and panel that need to be suppressed */
1685 	if (ictx->kc == KEY_MUTE ||
1686 	    ictx->dev_descr->flags & IMON_SUPPRESS_REPEATED_KEYS) {
1687 		if (ictx->kc == ictx->last_keycode &&
1688 		    ktime_ms_delta(t, prev_time) < ictx->idev->rep[REP_DELAY]) {
1689 			spin_unlock_irqrestore(&ictx->kc_lock, flags);
1690 			return;
1691 		}
1692 	}
1693 
1694 	prev_time = t;
1695 	kc = ictx->kc;
1696 
1697 	spin_unlock_irqrestore(&ictx->kc_lock, flags);
1698 
1699 	input_report_key(ictx->idev, kc, press_type);
1700 	input_sync(ictx->idev);
1701 
1702 	/* panel keys don't generate a release */
1703 	input_report_key(ictx->idev, kc, 0);
1704 	input_sync(ictx->idev);
1705 
1706 	spin_lock_irqsave(&ictx->kc_lock, flags);
1707 	ictx->last_keycode = kc;
1708 	spin_unlock_irqrestore(&ictx->kc_lock, flags);
1709 
1710 	return;
1711 
1712 not_input_data:
1713 	if (len != 8) {
1714 		dev_warn(dev, "imon %s: invalid incoming packet size (len = %d, intf%d)\n",
1715 			 __func__, len, intf);
1716 		return;
1717 	}
1718 
1719 	/* iMON 2.4G associate frame */
1720 	if (buf[0] == 0x00 &&
1721 	    buf[2] == 0xFF &&				/* REFID */
1722 	    buf[3] == 0xFF &&
1723 	    buf[4] == 0xFF &&
1724 	    buf[5] == 0xFF &&				/* iMON 2.4G */
1725 	   ((buf[6] == 0x4E && buf[7] == 0xDF) ||	/* LT */
1726 	    (buf[6] == 0x5E && buf[7] == 0xDF))) {	/* DT */
1727 		dev_warn(dev, "%s: remote associated refid=%02X\n",
1728 			 __func__, buf[1]);
1729 		ictx->rf_isassociating = false;
1730 	}
1731 }
1732 
1733 /*
1734  * Callback function for USB core API: receive data
1735  */
1736 static void usb_rx_callback_intf0(struct urb *urb)
1737 {
1738 	struct imon_context *ictx;
1739 	int intfnum = 0;
1740 
1741 	if (!urb)
1742 		return;
1743 
1744 	ictx = (struct imon_context *)urb->context;
1745 	if (!ictx)
1746 		return;
1747 
1748 	/*
1749 	 * if we get a callback before we're done configuring the hardware, we
1750 	 * can't yet process the data, as there's nowhere to send it, but we
1751 	 * still need to submit a new rx URB to avoid wedging the hardware
1752 	 */
1753 	if (!ictx->dev_present_intf0)
1754 		goto out;
1755 
1756 	switch (urb->status) {
1757 	case -ENOENT:		/* usbcore unlink successful! */
1758 		return;
1759 
1760 	case -ESHUTDOWN:	/* transport endpoint was shut down */
1761 		break;
1762 
1763 	case 0:
1764 		imon_incoming_packet(ictx, urb, intfnum);
1765 		break;
1766 
1767 	default:
1768 		dev_warn(ictx->dev, "imon %s: status(%d): ignored\n",
1769 			 __func__, urb->status);
1770 		break;
1771 	}
1772 
1773 out:
1774 	usb_submit_urb(ictx->rx_urb_intf0, GFP_ATOMIC);
1775 }
1776 
1777 static void usb_rx_callback_intf1(struct urb *urb)
1778 {
1779 	struct imon_context *ictx;
1780 	int intfnum = 1;
1781 
1782 	if (!urb)
1783 		return;
1784 
1785 	ictx = (struct imon_context *)urb->context;
1786 	if (!ictx)
1787 		return;
1788 
1789 	/*
1790 	 * if we get a callback before we're done configuring the hardware, we
1791 	 * can't yet process the data, as there's nowhere to send it, but we
1792 	 * still need to submit a new rx URB to avoid wedging the hardware
1793 	 */
1794 	if (!ictx->dev_present_intf1)
1795 		goto out;
1796 
1797 	switch (urb->status) {
1798 	case -ENOENT:		/* usbcore unlink successful! */
1799 		return;
1800 
1801 	case -ESHUTDOWN:	/* transport endpoint was shut down */
1802 		break;
1803 
1804 	case 0:
1805 		imon_incoming_packet(ictx, urb, intfnum);
1806 		break;
1807 
1808 	default:
1809 		dev_warn(ictx->dev, "imon %s: status(%d): ignored\n",
1810 			 __func__, urb->status);
1811 		break;
1812 	}
1813 
1814 out:
1815 	usb_submit_urb(ictx->rx_urb_intf1, GFP_ATOMIC);
1816 }
1817 
1818 /*
1819  * The 0x15c2:0xffdc device ID was used for umpteen different imon
1820  * devices, and all of them constantly spew interrupts, even when there
1821  * is no actual data to report. However, byte 6 of this buffer looks like
1822  * its unique across device variants, so we're trying to key off that to
1823  * figure out which display type (if any) and what IR protocol the device
1824  * actually supports. These devices have their IR protocol hard-coded into
1825  * their firmware, they can't be changed on the fly like the newer hardware.
1826  */
1827 static void imon_get_ffdc_type(struct imon_context *ictx)
1828 {
1829 	u8 ffdc_cfg_byte = ictx->usb_rx_buf[6];
1830 	u8 detected_display_type = IMON_DISPLAY_TYPE_NONE;
1831 	u64 allowed_protos = RC_PROTO_BIT_IMON;
1832 
1833 	switch (ffdc_cfg_byte) {
1834 	/* iMON Knob, no display, iMON IR + vol knob */
1835 	case 0x21:
1836 		dev_info(ictx->dev, "0xffdc iMON Knob, iMON IR");
1837 		ictx->display_supported = false;
1838 		break;
1839 	/* iMON 2.4G LT (usb stick), no display, iMON RF */
1840 	case 0x4e:
1841 		dev_info(ictx->dev, "0xffdc iMON 2.4G LT, iMON RF");
1842 		ictx->display_supported = false;
1843 		ictx->rf_device = true;
1844 		break;
1845 	/* iMON VFD, no IR (does have vol knob tho) */
1846 	case 0x35:
1847 		dev_info(ictx->dev, "0xffdc iMON VFD + knob, no IR");
1848 		detected_display_type = IMON_DISPLAY_TYPE_VFD;
1849 		break;
1850 	/* iMON VFD, iMON IR */
1851 	case 0x24:
1852 	case 0x30:
1853 	case 0x85:
1854 		dev_info(ictx->dev, "0xffdc iMON VFD, iMON IR");
1855 		detected_display_type = IMON_DISPLAY_TYPE_VFD;
1856 		break;
1857 	/* iMON VFD, MCE IR */
1858 	case 0x46:
1859 	case 0x9e:
1860 		dev_info(ictx->dev, "0xffdc iMON VFD, MCE IR");
1861 		detected_display_type = IMON_DISPLAY_TYPE_VFD;
1862 		allowed_protos = RC_PROTO_BIT_RC6_MCE;
1863 		break;
1864 	/* iMON VFD, iMON or MCE IR */
1865 	case 0x7e:
1866 		dev_info(ictx->dev, "0xffdc iMON VFD, iMON or MCE IR");
1867 		detected_display_type = IMON_DISPLAY_TYPE_VFD;
1868 		allowed_protos |= RC_PROTO_BIT_RC6_MCE;
1869 		break;
1870 	/* iMON LCD, MCE IR */
1871 	case 0x9f:
1872 		dev_info(ictx->dev, "0xffdc iMON LCD, MCE IR");
1873 		detected_display_type = IMON_DISPLAY_TYPE_LCD;
1874 		allowed_protos = RC_PROTO_BIT_RC6_MCE;
1875 		break;
1876 	/* no display, iMON IR */
1877 	case 0x26:
1878 		dev_info(ictx->dev, "0xffdc iMON Inside, iMON IR");
1879 		ictx->display_supported = false;
1880 		break;
1881 	/* Soundgraph iMON UltraBay */
1882 	case 0x98:
1883 		dev_info(ictx->dev, "0xffdc iMON UltraBay, LCD + IR");
1884 		detected_display_type = IMON_DISPLAY_TYPE_LCD;
1885 		allowed_protos = RC_PROTO_BIT_IMON | RC_PROTO_BIT_RC6_MCE;
1886 		ictx->dev_descr = &ultrabay_table;
1887 		break;
1888 
1889 	default:
1890 		dev_info(ictx->dev, "Unknown 0xffdc device, defaulting to VFD and iMON IR");
1891 		detected_display_type = IMON_DISPLAY_TYPE_VFD;
1892 		/*
1893 		 * We don't know which one it is, allow user to set the
1894 		 * RC6 one from userspace if IMON wasn't correct.
1895 		 */
1896 		allowed_protos |= RC_PROTO_BIT_RC6_MCE;
1897 		break;
1898 	}
1899 
1900 	printk(KERN_CONT " (id 0x%02x)\n", ffdc_cfg_byte);
1901 
1902 	ictx->display_type = detected_display_type;
1903 	ictx->rc_proto = allowed_protos;
1904 }
1905 
1906 static void imon_set_display_type(struct imon_context *ictx)
1907 {
1908 	u8 configured_display_type = IMON_DISPLAY_TYPE_VFD;
1909 
1910 	/*
1911 	 * Try to auto-detect the type of display if the user hasn't set
1912 	 * it by hand via the display_type modparam. Default is VFD.
1913 	 */
1914 
1915 	if (display_type == IMON_DISPLAY_TYPE_AUTO) {
1916 		switch (ictx->product) {
1917 		case 0xffdc:
1918 			/* set in imon_get_ffdc_type() */
1919 			configured_display_type = ictx->display_type;
1920 			break;
1921 		case 0x0034:
1922 		case 0x0035:
1923 			configured_display_type = IMON_DISPLAY_TYPE_VGA;
1924 			break;
1925 		case 0x0038:
1926 		case 0x0039:
1927 		case 0x0045:
1928 			configured_display_type = IMON_DISPLAY_TYPE_LCD;
1929 			break;
1930 		case 0x003c:
1931 		case 0x0041:
1932 		case 0x0042:
1933 		case 0x0043:
1934 			configured_display_type = IMON_DISPLAY_TYPE_NONE;
1935 			ictx->display_supported = false;
1936 			break;
1937 		case 0x0036:
1938 		case 0x0044:
1939 		default:
1940 			configured_display_type = IMON_DISPLAY_TYPE_VFD;
1941 			break;
1942 		}
1943 	} else {
1944 		configured_display_type = display_type;
1945 		if (display_type == IMON_DISPLAY_TYPE_NONE)
1946 			ictx->display_supported = false;
1947 		else
1948 			ictx->display_supported = true;
1949 		dev_info(ictx->dev, "%s: overriding display type to %d via modparam\n",
1950 			 __func__, display_type);
1951 	}
1952 
1953 	ictx->display_type = configured_display_type;
1954 }
1955 
1956 static struct rc_dev *imon_init_rdev(struct imon_context *ictx)
1957 {
1958 	struct rc_dev *rdev;
1959 	int ret;
1960 	static const unsigned char fp_packet[] = {
1961 		0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x88 };
1962 
1963 	rdev = rc_allocate_device(RC_DRIVER_SCANCODE);
1964 	if (!rdev) {
1965 		dev_err(ictx->dev, "remote control dev allocation failed\n");
1966 		goto out;
1967 	}
1968 
1969 	snprintf(ictx->name_rdev, sizeof(ictx->name_rdev),
1970 		 "iMON Remote (%04x:%04x)", ictx->vendor, ictx->product);
1971 	usb_make_path(ictx->usbdev_intf0, ictx->phys_rdev,
1972 		      sizeof(ictx->phys_rdev));
1973 	strlcat(ictx->phys_rdev, "/input0", sizeof(ictx->phys_rdev));
1974 
1975 	rdev->device_name = ictx->name_rdev;
1976 	rdev->input_phys = ictx->phys_rdev;
1977 	usb_to_input_id(ictx->usbdev_intf0, &rdev->input_id);
1978 	rdev->dev.parent = ictx->dev;
1979 
1980 	rdev->priv = ictx;
1981 	/* iMON PAD or MCE */
1982 	rdev->allowed_protocols = RC_PROTO_BIT_IMON | RC_PROTO_BIT_RC6_MCE;
1983 	rdev->change_protocol = imon_ir_change_protocol;
1984 	rdev->driver_name = MOD_NAME;
1985 
1986 	/* Enable front-panel buttons and/or knobs */
1987 	memcpy(ictx->usb_tx_buf, &fp_packet, sizeof(fp_packet));
1988 	ret = send_packet(ictx);
1989 	/* Not fatal, but warn about it */
1990 	if (ret)
1991 		dev_info(ictx->dev, "panel buttons/knobs setup failed\n");
1992 
1993 	if (ictx->product == 0xffdc) {
1994 		imon_get_ffdc_type(ictx);
1995 		rdev->allowed_protocols = ictx->rc_proto;
1996 	}
1997 
1998 	imon_set_display_type(ictx);
1999 
2000 	if (ictx->rc_proto == RC_PROTO_BIT_RC6_MCE)
2001 		rdev->map_name = RC_MAP_IMON_MCE;
2002 	else
2003 		rdev->map_name = RC_MAP_IMON_PAD;
2004 
2005 	ret = rc_register_device(rdev);
2006 	if (ret < 0) {
2007 		dev_err(ictx->dev, "remote input dev register failed\n");
2008 		goto out;
2009 	}
2010 
2011 	return rdev;
2012 
2013 out:
2014 	rc_free_device(rdev);
2015 	return NULL;
2016 }
2017 
2018 static struct input_dev *imon_init_idev(struct imon_context *ictx)
2019 {
2020 	const struct imon_panel_key_table *key_table;
2021 	struct input_dev *idev;
2022 	int ret, i;
2023 
2024 	key_table = ictx->dev_descr->key_table;
2025 
2026 	idev = input_allocate_device();
2027 	if (!idev)
2028 		goto out;
2029 
2030 	snprintf(ictx->name_idev, sizeof(ictx->name_idev),
2031 		 "iMON Panel, Knob and Mouse(%04x:%04x)",
2032 		 ictx->vendor, ictx->product);
2033 	idev->name = ictx->name_idev;
2034 
2035 	usb_make_path(ictx->usbdev_intf0, ictx->phys_idev,
2036 		      sizeof(ictx->phys_idev));
2037 	strlcat(ictx->phys_idev, "/input1", sizeof(ictx->phys_idev));
2038 	idev->phys = ictx->phys_idev;
2039 
2040 	idev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP) | BIT_MASK(EV_REL);
2041 
2042 	idev->keybit[BIT_WORD(BTN_MOUSE)] =
2043 		BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_RIGHT);
2044 	idev->relbit[0] = BIT_MASK(REL_X) | BIT_MASK(REL_Y) |
2045 		BIT_MASK(REL_WHEEL);
2046 
2047 	/* panel and/or knob code support */
2048 	for (i = 0; key_table[i].hw_code != 0; i++) {
2049 		u32 kc = key_table[i].keycode;
2050 		__set_bit(kc, idev->keybit);
2051 	}
2052 
2053 	usb_to_input_id(ictx->usbdev_intf0, &idev->id);
2054 	idev->dev.parent = ictx->dev;
2055 	input_set_drvdata(idev, ictx);
2056 
2057 	ret = input_register_device(idev);
2058 	if (ret < 0) {
2059 		dev_err(ictx->dev, "input dev register failed\n");
2060 		goto out;
2061 	}
2062 
2063 	return idev;
2064 
2065 out:
2066 	input_free_device(idev);
2067 	return NULL;
2068 }
2069 
2070 static struct input_dev *imon_init_touch(struct imon_context *ictx)
2071 {
2072 	struct input_dev *touch;
2073 	int ret;
2074 
2075 	touch = input_allocate_device();
2076 	if (!touch)
2077 		goto touch_alloc_failed;
2078 
2079 	snprintf(ictx->name_touch, sizeof(ictx->name_touch),
2080 		 "iMON USB Touchscreen (%04x:%04x)",
2081 		 ictx->vendor, ictx->product);
2082 	touch->name = ictx->name_touch;
2083 
2084 	usb_make_path(ictx->usbdev_intf1, ictx->phys_touch,
2085 		      sizeof(ictx->phys_touch));
2086 	strlcat(ictx->phys_touch, "/input2", sizeof(ictx->phys_touch));
2087 	touch->phys = ictx->phys_touch;
2088 
2089 	touch->evbit[0] =
2090 		BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
2091 	touch->keybit[BIT_WORD(BTN_TOUCH)] =
2092 		BIT_MASK(BTN_TOUCH);
2093 	input_set_abs_params(touch, ABS_X,
2094 			     0x00, 0xfff, 0, 0);
2095 	input_set_abs_params(touch, ABS_Y,
2096 			     0x00, 0xfff, 0, 0);
2097 
2098 	input_set_drvdata(touch, ictx);
2099 
2100 	usb_to_input_id(ictx->usbdev_intf1, &touch->id);
2101 	touch->dev.parent = ictx->dev;
2102 	ret = input_register_device(touch);
2103 	if (ret <  0) {
2104 		dev_info(ictx->dev, "touchscreen input dev register failed\n");
2105 		goto touch_register_failed;
2106 	}
2107 
2108 	return touch;
2109 
2110 touch_register_failed:
2111 	input_free_device(touch);
2112 
2113 touch_alloc_failed:
2114 	return NULL;
2115 }
2116 
2117 static bool imon_find_endpoints(struct imon_context *ictx,
2118 				struct usb_host_interface *iface_desc)
2119 {
2120 	struct usb_endpoint_descriptor *ep;
2121 	struct usb_endpoint_descriptor *rx_endpoint = NULL;
2122 	struct usb_endpoint_descriptor *tx_endpoint = NULL;
2123 	int ifnum = iface_desc->desc.bInterfaceNumber;
2124 	int num_endpts = iface_desc->desc.bNumEndpoints;
2125 	int i, ep_dir, ep_type;
2126 	bool ir_ep_found = false;
2127 	bool display_ep_found = false;
2128 	bool tx_control = false;
2129 
2130 	/*
2131 	 * Scan the endpoint list and set:
2132 	 *	first input endpoint = IR endpoint
2133 	 *	first output endpoint = display endpoint
2134 	 */
2135 	for (i = 0; i < num_endpts && !(ir_ep_found && display_ep_found); ++i) {
2136 		ep = &iface_desc->endpoint[i].desc;
2137 		ep_dir = ep->bEndpointAddress & USB_ENDPOINT_DIR_MASK;
2138 		ep_type = usb_endpoint_type(ep);
2139 
2140 		if (!ir_ep_found && ep_dir == USB_DIR_IN &&
2141 		    ep_type == USB_ENDPOINT_XFER_INT) {
2142 
2143 			rx_endpoint = ep;
2144 			ir_ep_found = true;
2145 			dev_dbg(ictx->dev, "%s: found IR endpoint\n", __func__);
2146 
2147 		} else if (!display_ep_found && ep_dir == USB_DIR_OUT &&
2148 			   ep_type == USB_ENDPOINT_XFER_INT) {
2149 			tx_endpoint = ep;
2150 			display_ep_found = true;
2151 			dev_dbg(ictx->dev, "%s: found display endpoint\n", __func__);
2152 		}
2153 	}
2154 
2155 	if (ifnum == 0) {
2156 		ictx->rx_endpoint_intf0 = rx_endpoint;
2157 		/*
2158 		 * tx is used to send characters to lcd/vfd, associate RF
2159 		 * remotes, set IR protocol, and maybe more...
2160 		 */
2161 		ictx->tx_endpoint = tx_endpoint;
2162 	} else {
2163 		ictx->rx_endpoint_intf1 = rx_endpoint;
2164 	}
2165 
2166 	/*
2167 	 * If we didn't find a display endpoint, this is probably one of the
2168 	 * newer iMON devices that use control urb instead of interrupt
2169 	 */
2170 	if (!display_ep_found) {
2171 		tx_control = true;
2172 		display_ep_found = true;
2173 		dev_dbg(ictx->dev, "%s: device uses control endpoint, not interface OUT endpoint\n",
2174 			__func__);
2175 	}
2176 
2177 	/*
2178 	 * Some iMON receivers have no display. Unfortunately, it seems
2179 	 * that SoundGraph recycles device IDs between devices both with
2180 	 * and without... :\
2181 	 */
2182 	if (ictx->display_type == IMON_DISPLAY_TYPE_NONE) {
2183 		display_ep_found = false;
2184 		dev_dbg(ictx->dev, "%s: device has no display\n", __func__);
2185 	}
2186 
2187 	/*
2188 	 * iMON Touch devices have a VGA touchscreen, but no "display", as
2189 	 * that refers to e.g. /dev/lcd0 (a character device LCD or VFD).
2190 	 */
2191 	if (ictx->display_type == IMON_DISPLAY_TYPE_VGA) {
2192 		display_ep_found = false;
2193 		dev_dbg(ictx->dev, "%s: iMON Touch device found\n", __func__);
2194 	}
2195 
2196 	/* Input endpoint is mandatory */
2197 	if (!ir_ep_found)
2198 		pr_err("no valid input (IR) endpoint found\n");
2199 
2200 	ictx->tx_control = tx_control;
2201 
2202 	if (display_ep_found)
2203 		ictx->display_supported = true;
2204 
2205 	return ir_ep_found;
2206 
2207 }
2208 
2209 static struct imon_context *imon_init_intf0(struct usb_interface *intf,
2210 					    const struct usb_device_id *id)
2211 {
2212 	struct imon_context *ictx;
2213 	struct urb *rx_urb;
2214 	struct urb *tx_urb;
2215 	struct device *dev = &intf->dev;
2216 	struct usb_host_interface *iface_desc;
2217 	int ret = -ENOMEM;
2218 
2219 	ictx = kzalloc(sizeof(*ictx), GFP_KERNEL);
2220 	if (!ictx)
2221 		goto exit;
2222 
2223 	rx_urb = usb_alloc_urb(0, GFP_KERNEL);
2224 	if (!rx_urb)
2225 		goto rx_urb_alloc_failed;
2226 	tx_urb = usb_alloc_urb(0, GFP_KERNEL);
2227 	if (!tx_urb)
2228 		goto tx_urb_alloc_failed;
2229 
2230 	mutex_init(&ictx->lock);
2231 	spin_lock_init(&ictx->kc_lock);
2232 
2233 	mutex_lock(&ictx->lock);
2234 
2235 	ictx->dev = dev;
2236 	ictx->usbdev_intf0 = usb_get_dev(interface_to_usbdev(intf));
2237 	ictx->rx_urb_intf0 = rx_urb;
2238 	ictx->tx_urb = tx_urb;
2239 	ictx->rf_device = false;
2240 
2241 	init_completion(&ictx->tx.finished);
2242 
2243 	ictx->vendor  = le16_to_cpu(ictx->usbdev_intf0->descriptor.idVendor);
2244 	ictx->product = le16_to_cpu(ictx->usbdev_intf0->descriptor.idProduct);
2245 
2246 	/* save drive info for later accessing the panel/knob key table */
2247 	ictx->dev_descr = (struct imon_usb_dev_descr *)id->driver_info;
2248 	/* default send_packet delay is 5ms but some devices need more */
2249 	ictx->send_packet_delay = ictx->dev_descr->flags &
2250 				  IMON_NEED_20MS_PKT_DELAY ? 20 : 5;
2251 
2252 	ret = -ENODEV;
2253 	iface_desc = intf->cur_altsetting;
2254 	if (!imon_find_endpoints(ictx, iface_desc)) {
2255 		goto find_endpoint_failed;
2256 	}
2257 
2258 	usb_fill_int_urb(ictx->rx_urb_intf0, ictx->usbdev_intf0,
2259 		usb_rcvintpipe(ictx->usbdev_intf0,
2260 			ictx->rx_endpoint_intf0->bEndpointAddress),
2261 		ictx->usb_rx_buf, sizeof(ictx->usb_rx_buf),
2262 		usb_rx_callback_intf0, ictx,
2263 		ictx->rx_endpoint_intf0->bInterval);
2264 
2265 	ret = usb_submit_urb(ictx->rx_urb_intf0, GFP_KERNEL);
2266 	if (ret) {
2267 		pr_err("usb_submit_urb failed for intf0 (%d)\n", ret);
2268 		goto urb_submit_failed;
2269 	}
2270 
2271 	ictx->idev = imon_init_idev(ictx);
2272 	if (!ictx->idev) {
2273 		dev_err(dev, "%s: input device setup failed\n", __func__);
2274 		goto idev_setup_failed;
2275 	}
2276 
2277 	ictx->rdev = imon_init_rdev(ictx);
2278 	if (!ictx->rdev) {
2279 		dev_err(dev, "%s: rc device setup failed\n", __func__);
2280 		goto rdev_setup_failed;
2281 	}
2282 
2283 	ictx->dev_present_intf0 = true;
2284 
2285 	mutex_unlock(&ictx->lock);
2286 	return ictx;
2287 
2288 rdev_setup_failed:
2289 	input_unregister_device(ictx->idev);
2290 idev_setup_failed:
2291 	usb_kill_urb(ictx->rx_urb_intf0);
2292 urb_submit_failed:
2293 find_endpoint_failed:
2294 	usb_put_dev(ictx->usbdev_intf0);
2295 	mutex_unlock(&ictx->lock);
2296 	usb_free_urb(tx_urb);
2297 tx_urb_alloc_failed:
2298 	usb_free_urb(rx_urb);
2299 rx_urb_alloc_failed:
2300 	kfree(ictx);
2301 exit:
2302 	dev_err(dev, "unable to initialize intf0, err %d\n", ret);
2303 
2304 	return NULL;
2305 }
2306 
2307 static struct imon_context *imon_init_intf1(struct usb_interface *intf,
2308 					    struct imon_context *ictx)
2309 {
2310 	struct urb *rx_urb;
2311 	struct usb_host_interface *iface_desc;
2312 	int ret = -ENOMEM;
2313 
2314 	rx_urb = usb_alloc_urb(0, GFP_KERNEL);
2315 	if (!rx_urb)
2316 		goto rx_urb_alloc_failed;
2317 
2318 	mutex_lock(&ictx->lock);
2319 
2320 	if (ictx->display_type == IMON_DISPLAY_TYPE_VGA) {
2321 		timer_setup(&ictx->ttimer, imon_touch_display_timeout, 0);
2322 	}
2323 
2324 	ictx->usbdev_intf1 = usb_get_dev(interface_to_usbdev(intf));
2325 	ictx->rx_urb_intf1 = rx_urb;
2326 
2327 	ret = -ENODEV;
2328 	iface_desc = intf->cur_altsetting;
2329 	if (!imon_find_endpoints(ictx, iface_desc))
2330 		goto find_endpoint_failed;
2331 
2332 	if (ictx->display_type == IMON_DISPLAY_TYPE_VGA) {
2333 		ictx->touch = imon_init_touch(ictx);
2334 		if (!ictx->touch)
2335 			goto touch_setup_failed;
2336 	} else
2337 		ictx->touch = NULL;
2338 
2339 	usb_fill_int_urb(ictx->rx_urb_intf1, ictx->usbdev_intf1,
2340 		usb_rcvintpipe(ictx->usbdev_intf1,
2341 			ictx->rx_endpoint_intf1->bEndpointAddress),
2342 		ictx->usb_rx_buf, sizeof(ictx->usb_rx_buf),
2343 		usb_rx_callback_intf1, ictx,
2344 		ictx->rx_endpoint_intf1->bInterval);
2345 
2346 	ret = usb_submit_urb(ictx->rx_urb_intf1, GFP_KERNEL);
2347 
2348 	if (ret) {
2349 		pr_err("usb_submit_urb failed for intf1 (%d)\n", ret);
2350 		goto urb_submit_failed;
2351 	}
2352 
2353 	ictx->dev_present_intf1 = true;
2354 
2355 	mutex_unlock(&ictx->lock);
2356 	return ictx;
2357 
2358 urb_submit_failed:
2359 	if (ictx->touch)
2360 		input_unregister_device(ictx->touch);
2361 touch_setup_failed:
2362 find_endpoint_failed:
2363 	usb_put_dev(ictx->usbdev_intf1);
2364 	mutex_unlock(&ictx->lock);
2365 	usb_free_urb(rx_urb);
2366 rx_urb_alloc_failed:
2367 	dev_err(ictx->dev, "unable to initialize intf1, err %d\n", ret);
2368 
2369 	return NULL;
2370 }
2371 
2372 static void imon_init_display(struct imon_context *ictx,
2373 			      struct usb_interface *intf)
2374 {
2375 	int ret;
2376 
2377 	dev_dbg(ictx->dev, "Registering iMON display with sysfs\n");
2378 
2379 	/* set up sysfs entry for built-in clock */
2380 	ret = sysfs_create_group(&intf->dev.kobj, &imon_display_attr_group);
2381 	if (ret)
2382 		dev_err(ictx->dev, "Could not create display sysfs entries(%d)",
2383 			ret);
2384 
2385 	if (ictx->display_type == IMON_DISPLAY_TYPE_LCD)
2386 		ret = usb_register_dev(intf, &imon_lcd_class);
2387 	else
2388 		ret = usb_register_dev(intf, &imon_vfd_class);
2389 	if (ret)
2390 		/* Not a fatal error, so ignore */
2391 		dev_info(ictx->dev, "could not get a minor number for display\n");
2392 
2393 }
2394 
2395 /*
2396  * Callback function for USB core API: Probe
2397  */
2398 static int imon_probe(struct usb_interface *interface,
2399 		      const struct usb_device_id *id)
2400 {
2401 	struct usb_device *usbdev = NULL;
2402 	struct usb_host_interface *iface_desc = NULL;
2403 	struct usb_interface *first_if;
2404 	struct device *dev = &interface->dev;
2405 	int ifnum, sysfs_err;
2406 	int ret = 0;
2407 	struct imon_context *ictx = NULL;
2408 	struct imon_context *first_if_ctx = NULL;
2409 	u16 vendor, product;
2410 
2411 	usbdev     = usb_get_dev(interface_to_usbdev(interface));
2412 	iface_desc = interface->cur_altsetting;
2413 	ifnum      = iface_desc->desc.bInterfaceNumber;
2414 	vendor     = le16_to_cpu(usbdev->descriptor.idVendor);
2415 	product    = le16_to_cpu(usbdev->descriptor.idProduct);
2416 
2417 	dev_dbg(dev, "%s: found iMON device (%04x:%04x, intf%d)\n",
2418 		__func__, vendor, product, ifnum);
2419 
2420 	/* prevent races probing devices w/multiple interfaces */
2421 	mutex_lock(&driver_lock);
2422 
2423 	first_if = usb_ifnum_to_if(usbdev, 0);
2424 	if (!first_if) {
2425 		ret = -ENODEV;
2426 		goto fail;
2427 	}
2428 
2429 	first_if_ctx = usb_get_intfdata(first_if);
2430 
2431 	if (ifnum == 0) {
2432 		ictx = imon_init_intf0(interface, id);
2433 		if (!ictx) {
2434 			pr_err("failed to initialize context!\n");
2435 			ret = -ENODEV;
2436 			goto fail;
2437 		}
2438 
2439 	} else {
2440 		/* this is the secondary interface on the device */
2441 
2442 		/* fail early if first intf failed to register */
2443 		if (!first_if_ctx) {
2444 			ret = -ENODEV;
2445 			goto fail;
2446 		}
2447 
2448 		ictx = imon_init_intf1(interface, first_if_ctx);
2449 		if (!ictx) {
2450 			pr_err("failed to attach to context!\n");
2451 			ret = -ENODEV;
2452 			goto fail;
2453 		}
2454 
2455 	}
2456 
2457 	usb_set_intfdata(interface, ictx);
2458 
2459 	if (ifnum == 0) {
2460 		mutex_lock(&ictx->lock);
2461 
2462 		if (product == 0xffdc && ictx->rf_device) {
2463 			sysfs_err = sysfs_create_group(&interface->dev.kobj,
2464 						       &imon_rf_attr_group);
2465 			if (sysfs_err)
2466 				pr_err("Could not create RF sysfs entries(%d)\n",
2467 				       sysfs_err);
2468 		}
2469 
2470 		if (ictx->display_supported)
2471 			imon_init_display(ictx, interface);
2472 
2473 		mutex_unlock(&ictx->lock);
2474 	}
2475 
2476 	dev_info(dev, "iMON device (%04x:%04x, intf%d) on usb<%d:%d> initialized\n",
2477 		 vendor, product, ifnum,
2478 		 usbdev->bus->busnum, usbdev->devnum);
2479 
2480 	mutex_unlock(&driver_lock);
2481 	usb_put_dev(usbdev);
2482 
2483 	return 0;
2484 
2485 fail:
2486 	mutex_unlock(&driver_lock);
2487 	usb_put_dev(usbdev);
2488 	dev_err(dev, "unable to register, err %d\n", ret);
2489 
2490 	return ret;
2491 }
2492 
2493 /*
2494  * Callback function for USB core API: disconnect
2495  */
2496 static void imon_disconnect(struct usb_interface *interface)
2497 {
2498 	struct imon_context *ictx;
2499 	struct device *dev;
2500 	int ifnum;
2501 
2502 	/* prevent races with multi-interface device probing and display_open */
2503 	mutex_lock(&driver_lock);
2504 
2505 	ictx = usb_get_intfdata(interface);
2506 	dev = ictx->dev;
2507 	ifnum = interface->cur_altsetting->desc.bInterfaceNumber;
2508 
2509 	/*
2510 	 * sysfs_remove_group is safe to call even if sysfs_create_group
2511 	 * hasn't been called
2512 	 */
2513 	sysfs_remove_group(&interface->dev.kobj, &imon_display_attr_group);
2514 	sysfs_remove_group(&interface->dev.kobj, &imon_rf_attr_group);
2515 
2516 	usb_set_intfdata(interface, NULL);
2517 
2518 	/* Abort ongoing write */
2519 	if (ictx->tx.busy) {
2520 		usb_kill_urb(ictx->tx_urb);
2521 		complete(&ictx->tx.finished);
2522 	}
2523 
2524 	if (ifnum == 0) {
2525 		ictx->dev_present_intf0 = false;
2526 		usb_kill_urb(ictx->rx_urb_intf0);
2527 		usb_put_dev(ictx->usbdev_intf0);
2528 		input_unregister_device(ictx->idev);
2529 		rc_unregister_device(ictx->rdev);
2530 		if (ictx->display_supported) {
2531 			if (ictx->display_type == IMON_DISPLAY_TYPE_LCD)
2532 				usb_deregister_dev(interface, &imon_lcd_class);
2533 			else if (ictx->display_type == IMON_DISPLAY_TYPE_VFD)
2534 				usb_deregister_dev(interface, &imon_vfd_class);
2535 		}
2536 	} else {
2537 		ictx->dev_present_intf1 = false;
2538 		usb_kill_urb(ictx->rx_urb_intf1);
2539 		usb_put_dev(ictx->usbdev_intf1);
2540 		if (ictx->display_type == IMON_DISPLAY_TYPE_VGA) {
2541 			input_unregister_device(ictx->touch);
2542 			del_timer_sync(&ictx->ttimer);
2543 		}
2544 	}
2545 
2546 	if (!ictx->dev_present_intf0 && !ictx->dev_present_intf1)
2547 		free_imon_context(ictx);
2548 
2549 	mutex_unlock(&driver_lock);
2550 
2551 	dev_dbg(dev, "%s: iMON device (intf%d) disconnected\n",
2552 		__func__, ifnum);
2553 }
2554 
2555 static int imon_suspend(struct usb_interface *intf, pm_message_t message)
2556 {
2557 	struct imon_context *ictx = usb_get_intfdata(intf);
2558 	int ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
2559 
2560 	if (ifnum == 0)
2561 		usb_kill_urb(ictx->rx_urb_intf0);
2562 	else
2563 		usb_kill_urb(ictx->rx_urb_intf1);
2564 
2565 	return 0;
2566 }
2567 
2568 static int imon_resume(struct usb_interface *intf)
2569 {
2570 	int rc = 0;
2571 	struct imon_context *ictx = usb_get_intfdata(intf);
2572 	int ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
2573 
2574 	if (ifnum == 0) {
2575 		usb_fill_int_urb(ictx->rx_urb_intf0, ictx->usbdev_intf0,
2576 			usb_rcvintpipe(ictx->usbdev_intf0,
2577 				ictx->rx_endpoint_intf0->bEndpointAddress),
2578 			ictx->usb_rx_buf, sizeof(ictx->usb_rx_buf),
2579 			usb_rx_callback_intf0, ictx,
2580 			ictx->rx_endpoint_intf0->bInterval);
2581 
2582 		rc = usb_submit_urb(ictx->rx_urb_intf0, GFP_ATOMIC);
2583 
2584 	} else {
2585 		usb_fill_int_urb(ictx->rx_urb_intf1, ictx->usbdev_intf1,
2586 			usb_rcvintpipe(ictx->usbdev_intf1,
2587 				ictx->rx_endpoint_intf1->bEndpointAddress),
2588 			ictx->usb_rx_buf, sizeof(ictx->usb_rx_buf),
2589 			usb_rx_callback_intf1, ictx,
2590 			ictx->rx_endpoint_intf1->bInterval);
2591 
2592 		rc = usb_submit_urb(ictx->rx_urb_intf1, GFP_ATOMIC);
2593 	}
2594 
2595 	return rc;
2596 }
2597 
2598 module_usb_driver(imon_driver);
2599