xref: /linux/drivers/media/rc/imon.c (revision d53b8e36925256097a08d7cb749198d85cbf9b2b)
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 	 * Fields for deferring free_imon_context().
158 	 *
159 	 * Since reference to "struct imon_context" is stored into
160 	 * "struct file"->private_data, we need to remember
161 	 * how many file descriptors might access this "struct imon_context".
162 	 */
163 	refcount_t users;
164 	/*
165 	 * Use a flag for telling display_open()/vfd_write()/lcd_write() that
166 	 * imon_disconnect() was already called.
167 	 */
168 	bool disconnected;
169 	/*
170 	 * We need to wait for RCU grace period in order to allow
171 	 * display_open() to safely check ->disconnected and increment ->users.
172 	 */
173 	struct rcu_head rcu;
174 };
175 
176 #define TOUCH_TIMEOUT	(HZ/30)
177 
178 /* vfd character device file operations */
179 static const struct file_operations vfd_fops = {
180 	.owner		= THIS_MODULE,
181 	.open		= display_open,
182 	.write		= vfd_write,
183 	.release	= display_close,
184 	.llseek		= noop_llseek,
185 };
186 
187 /* lcd character device file operations */
188 static const struct file_operations lcd_fops = {
189 	.owner		= THIS_MODULE,
190 	.open		= display_open,
191 	.write		= lcd_write,
192 	.release	= display_close,
193 	.llseek		= noop_llseek,
194 };
195 
196 enum {
197 	IMON_DISPLAY_TYPE_AUTO = 0,
198 	IMON_DISPLAY_TYPE_VFD  = 1,
199 	IMON_DISPLAY_TYPE_LCD  = 2,
200 	IMON_DISPLAY_TYPE_VGA  = 3,
201 	IMON_DISPLAY_TYPE_NONE = 4,
202 };
203 
204 enum {
205 	IMON_KEY_IMON	= 0,
206 	IMON_KEY_MCE	= 1,
207 	IMON_KEY_PANEL	= 2,
208 };
209 
210 static struct usb_class_driver imon_vfd_class = {
211 	.name		= DEVICE_NAME,
212 	.fops		= &vfd_fops,
213 	.minor_base	= DISPLAY_MINOR_BASE,
214 };
215 
216 static struct usb_class_driver imon_lcd_class = {
217 	.name		= DEVICE_NAME,
218 	.fops		= &lcd_fops,
219 	.minor_base	= DISPLAY_MINOR_BASE,
220 };
221 
222 /* imon receiver front panel/knob key table */
223 static const struct imon_usb_dev_descr imon_default_table = {
224 	.flags = IMON_NO_FLAGS,
225 	.key_table = {
226 		{ 0x000000000f00ffeell, KEY_MEDIA }, /* Go */
227 		{ 0x000000001200ffeell, KEY_UP },
228 		{ 0x000000001300ffeell, KEY_DOWN },
229 		{ 0x000000001400ffeell, KEY_LEFT },
230 		{ 0x000000001500ffeell, KEY_RIGHT },
231 		{ 0x000000001600ffeell, KEY_ENTER },
232 		{ 0x000000001700ffeell, KEY_ESC },
233 		{ 0x000000001f00ffeell, KEY_AUDIO },
234 		{ 0x000000002000ffeell, KEY_VIDEO },
235 		{ 0x000000002100ffeell, KEY_CAMERA },
236 		{ 0x000000002700ffeell, KEY_DVD },
237 		{ 0x000000002300ffeell, KEY_TV },
238 		{ 0x000000002b00ffeell, KEY_EXIT },
239 		{ 0x000000002c00ffeell, KEY_SELECT },
240 		{ 0x000000002d00ffeell, KEY_MENU },
241 		{ 0x000000000500ffeell, KEY_PREVIOUS },
242 		{ 0x000000000700ffeell, KEY_REWIND },
243 		{ 0x000000000400ffeell, KEY_STOP },
244 		{ 0x000000003c00ffeell, KEY_PLAYPAUSE },
245 		{ 0x000000000800ffeell, KEY_FASTFORWARD },
246 		{ 0x000000000600ffeell, KEY_NEXT },
247 		{ 0x000000010000ffeell, KEY_RIGHT },
248 		{ 0x000001000000ffeell, KEY_LEFT },
249 		{ 0x000000003d00ffeell, KEY_SELECT },
250 		{ 0x000100000000ffeell, KEY_VOLUMEUP },
251 		{ 0x010000000000ffeell, KEY_VOLUMEDOWN },
252 		{ 0x000000000100ffeell, KEY_MUTE },
253 		/* 0xffdc iMON MCE VFD */
254 		{ 0x00010000ffffffeell, KEY_VOLUMEUP },
255 		{ 0x01000000ffffffeell, KEY_VOLUMEDOWN },
256 		{ 0x00000001ffffffeell, KEY_MUTE },
257 		{ 0x0000000fffffffeell, KEY_MEDIA },
258 		{ 0x00000012ffffffeell, KEY_UP },
259 		{ 0x00000013ffffffeell, KEY_DOWN },
260 		{ 0x00000014ffffffeell, KEY_LEFT },
261 		{ 0x00000015ffffffeell, KEY_RIGHT },
262 		{ 0x00000016ffffffeell, KEY_ENTER },
263 		{ 0x00000017ffffffeell, KEY_ESC },
264 		/* iMON Knob values */
265 		{ 0x000100ffffffffeell, KEY_VOLUMEUP },
266 		{ 0x010000ffffffffeell, KEY_VOLUMEDOWN },
267 		{ 0x000008ffffffffeell, KEY_MUTE },
268 		{ 0, KEY_RESERVED },
269 	}
270 };
271 
272 static const struct imon_usb_dev_descr imon_OEM_VFD = {
273 	.flags = IMON_NEED_20MS_PKT_DELAY,
274 	.key_table = {
275 		{ 0x000000000f00ffeell, KEY_MEDIA }, /* Go */
276 		{ 0x000000001200ffeell, KEY_UP },
277 		{ 0x000000001300ffeell, KEY_DOWN },
278 		{ 0x000000001400ffeell, KEY_LEFT },
279 		{ 0x000000001500ffeell, KEY_RIGHT },
280 		{ 0x000000001600ffeell, KEY_ENTER },
281 		{ 0x000000001700ffeell, KEY_ESC },
282 		{ 0x000000001f00ffeell, KEY_AUDIO },
283 		{ 0x000000002b00ffeell, KEY_EXIT },
284 		{ 0x000000002c00ffeell, KEY_SELECT },
285 		{ 0x000000002d00ffeell, KEY_MENU },
286 		{ 0x000000000500ffeell, KEY_PREVIOUS },
287 		{ 0x000000000700ffeell, KEY_REWIND },
288 		{ 0x000000000400ffeell, KEY_STOP },
289 		{ 0x000000003c00ffeell, KEY_PLAYPAUSE },
290 		{ 0x000000000800ffeell, KEY_FASTFORWARD },
291 		{ 0x000000000600ffeell, KEY_NEXT },
292 		{ 0x000000010000ffeell, KEY_RIGHT },
293 		{ 0x000001000000ffeell, KEY_LEFT },
294 		{ 0x000000003d00ffeell, KEY_SELECT },
295 		{ 0x000100000000ffeell, KEY_VOLUMEUP },
296 		{ 0x010000000000ffeell, KEY_VOLUMEDOWN },
297 		{ 0x000000000100ffeell, KEY_MUTE },
298 		/* 0xffdc iMON MCE VFD */
299 		{ 0x00010000ffffffeell, KEY_VOLUMEUP },
300 		{ 0x01000000ffffffeell, KEY_VOLUMEDOWN },
301 		{ 0x00000001ffffffeell, KEY_MUTE },
302 		{ 0x0000000fffffffeell, KEY_MEDIA },
303 		{ 0x00000012ffffffeell, KEY_UP },
304 		{ 0x00000013ffffffeell, KEY_DOWN },
305 		{ 0x00000014ffffffeell, KEY_LEFT },
306 		{ 0x00000015ffffffeell, KEY_RIGHT },
307 		{ 0x00000016ffffffeell, KEY_ENTER },
308 		{ 0x00000017ffffffeell, KEY_ESC },
309 		/* iMON Knob values */
310 		{ 0x000100ffffffffeell, KEY_VOLUMEUP },
311 		{ 0x010000ffffffffeell, KEY_VOLUMEDOWN },
312 		{ 0x000008ffffffffeell, KEY_MUTE },
313 		{ 0, KEY_RESERVED },
314 	}
315 };
316 
317 /* imon receiver front panel/knob key table for DH102*/
318 static const struct imon_usb_dev_descr imon_DH102 = {
319 	.flags = IMON_NO_FLAGS,
320 	.key_table = {
321 		{ 0x000100000000ffeell, KEY_VOLUMEUP },
322 		{ 0x010000000000ffeell, KEY_VOLUMEDOWN },
323 		{ 0x000000010000ffeell, KEY_MUTE },
324 		{ 0x0000000f0000ffeell, KEY_MEDIA },
325 		{ 0x000000120000ffeell, KEY_UP },
326 		{ 0x000000130000ffeell, KEY_DOWN },
327 		{ 0x000000140000ffeell, KEY_LEFT },
328 		{ 0x000000150000ffeell, KEY_RIGHT },
329 		{ 0x000000160000ffeell, KEY_ENTER },
330 		{ 0x000000170000ffeell, KEY_ESC },
331 		{ 0x0000002b0000ffeell, KEY_EXIT },
332 		{ 0x0000002c0000ffeell, KEY_SELECT },
333 		{ 0x0000002d0000ffeell, KEY_MENU },
334 		{ 0, KEY_RESERVED }
335 	}
336 };
337 
338 /* imon ultrabay front panel key table */
339 static const struct imon_usb_dev_descr ultrabay_table = {
340 	.flags = IMON_SUPPRESS_REPEATED_KEYS,
341 	.key_table = {
342 		{ 0x0000000f0000ffeell, KEY_MEDIA },      /* Go */
343 		{ 0x000000000100ffeell, KEY_UP },
344 		{ 0x000000000001ffeell, KEY_DOWN },
345 		{ 0x000000160000ffeell, KEY_ENTER },
346 		{ 0x0000001f0000ffeell, KEY_AUDIO },      /* Music */
347 		{ 0x000000200000ffeell, KEY_VIDEO },      /* Movie */
348 		{ 0x000000210000ffeell, KEY_CAMERA },     /* Photo */
349 		{ 0x000000270000ffeell, KEY_DVD },        /* DVD */
350 		{ 0x000000230000ffeell, KEY_TV },         /* TV */
351 		{ 0x000000050000ffeell, KEY_PREVIOUS },   /* Previous */
352 		{ 0x000000070000ffeell, KEY_REWIND },
353 		{ 0x000000040000ffeell, KEY_STOP },
354 		{ 0x000000020000ffeell, KEY_PLAYPAUSE },
355 		{ 0x000000080000ffeell, KEY_FASTFORWARD },
356 		{ 0x000000060000ffeell, KEY_NEXT },       /* Next */
357 		{ 0x000100000000ffeell, KEY_VOLUMEUP },
358 		{ 0x010000000000ffeell, KEY_VOLUMEDOWN },
359 		{ 0x000000010000ffeell, KEY_MUTE },
360 		{ 0, KEY_RESERVED },
361 	}
362 };
363 
364 /*
365  * USB Device ID for iMON USB Control Boards
366  *
367  * The Windows drivers contain 6 different inf files, more or less one for
368  * each new device until the 0x0034-0x0046 devices, which all use the same
369  * driver. Some of the devices in the 34-46 range haven't been definitively
370  * identified yet. Early devices have either a TriGem Computer, Inc. or a
371  * Samsung vendor ID (0x0aa8 and 0x04e8 respectively), while all later
372  * devices use the SoundGraph vendor ID (0x15c2). This driver only supports
373  * the ffdc and later devices, which do onboard decoding.
374  */
375 static const struct usb_device_id imon_usb_id_table[] = {
376 	/*
377 	 * Several devices with this same device ID, all use iMON_PAD.inf
378 	 * SoundGraph iMON PAD (IR & VFD)
379 	 * SoundGraph iMON PAD (IR & LCD)
380 	 * SoundGraph iMON Knob (IR only)
381 	 */
382 	{ USB_DEVICE(0x15c2, 0xffdc),
383 	  .driver_info = (unsigned long)&imon_default_table },
384 
385 	/*
386 	 * Newer devices, all driven by the latest iMON Windows driver, full
387 	 * list of device IDs extracted via 'strings Setup/data1.hdr |grep 15c2'
388 	 * Need user input to fill in details on unknown devices.
389 	 */
390 	/* SoundGraph iMON OEM Touch LCD (IR & 7" VGA LCD) */
391 	{ USB_DEVICE(0x15c2, 0x0034),
392 	  .driver_info = (unsigned long)&imon_DH102 },
393 	/* SoundGraph iMON OEM Touch LCD (IR & 4.3" VGA LCD) */
394 	{ USB_DEVICE(0x15c2, 0x0035),
395 	  .driver_info = (unsigned long)&imon_default_table},
396 	/* SoundGraph iMON OEM VFD (IR & VFD) */
397 	{ USB_DEVICE(0x15c2, 0x0036),
398 	  .driver_info = (unsigned long)&imon_OEM_VFD },
399 	/* device specifics unknown */
400 	{ USB_DEVICE(0x15c2, 0x0037),
401 	  .driver_info = (unsigned long)&imon_default_table},
402 	/* SoundGraph iMON OEM LCD (IR & LCD) */
403 	{ USB_DEVICE(0x15c2, 0x0038),
404 	  .driver_info = (unsigned long)&imon_default_table},
405 	/* SoundGraph iMON UltraBay (IR & LCD) */
406 	{ USB_DEVICE(0x15c2, 0x0039),
407 	  .driver_info = (unsigned long)&imon_default_table},
408 	/* device specifics unknown */
409 	{ USB_DEVICE(0x15c2, 0x003a),
410 	  .driver_info = (unsigned long)&imon_default_table},
411 	/* device specifics unknown */
412 	{ USB_DEVICE(0x15c2, 0x003b),
413 	  .driver_info = (unsigned long)&imon_default_table},
414 	/* SoundGraph iMON OEM Inside (IR only) */
415 	{ USB_DEVICE(0x15c2, 0x003c),
416 	  .driver_info = (unsigned long)&imon_default_table},
417 	/* device specifics unknown */
418 	{ USB_DEVICE(0x15c2, 0x003d),
419 	  .driver_info = (unsigned long)&imon_default_table},
420 	/* device specifics unknown */
421 	{ USB_DEVICE(0x15c2, 0x003e),
422 	  .driver_info = (unsigned long)&imon_default_table},
423 	/* device specifics unknown */
424 	{ USB_DEVICE(0x15c2, 0x003f),
425 	  .driver_info = (unsigned long)&imon_default_table},
426 	/* device specifics unknown */
427 	{ USB_DEVICE(0x15c2, 0x0040),
428 	  .driver_info = (unsigned long)&imon_default_table},
429 	/* SoundGraph iMON MINI (IR only) */
430 	{ USB_DEVICE(0x15c2, 0x0041),
431 	  .driver_info = (unsigned long)&imon_default_table},
432 	/* Antec Veris Multimedia Station EZ External (IR only) */
433 	{ USB_DEVICE(0x15c2, 0x0042),
434 	  .driver_info = (unsigned long)&imon_default_table},
435 	/* Antec Veris Multimedia Station Basic Internal (IR only) */
436 	{ USB_DEVICE(0x15c2, 0x0043),
437 	  .driver_info = (unsigned long)&imon_default_table},
438 	/* Antec Veris Multimedia Station Elite (IR & VFD) */
439 	{ USB_DEVICE(0x15c2, 0x0044),
440 	  .driver_info = (unsigned long)&imon_default_table},
441 	/* Antec Veris Multimedia Station Premiere (IR & LCD) */
442 	{ USB_DEVICE(0x15c2, 0x0045),
443 	  .driver_info = (unsigned long)&imon_default_table},
444 	/* device specifics unknown */
445 	{ USB_DEVICE(0x15c2, 0x0046),
446 	  .driver_info = (unsigned long)&imon_default_table},
447 	{}
448 };
449 
450 /* USB Device data */
451 static struct usb_driver imon_driver = {
452 	.name		= MOD_NAME,
453 	.probe		= imon_probe,
454 	.disconnect	= imon_disconnect,
455 	.suspend	= imon_suspend,
456 	.resume		= imon_resume,
457 	.id_table	= imon_usb_id_table,
458 };
459 
460 /* Module bookkeeping bits */
461 MODULE_AUTHOR(MOD_AUTHOR);
462 MODULE_DESCRIPTION(MOD_DESC);
463 MODULE_VERSION(MOD_VERSION);
464 MODULE_LICENSE("GPL");
465 MODULE_DEVICE_TABLE(usb, imon_usb_id_table);
466 
467 static bool debug;
468 module_param(debug, bool, S_IRUGO | S_IWUSR);
469 MODULE_PARM_DESC(debug, "Debug messages: 0=no, 1=yes (default: no)");
470 
471 /* lcd, vfd, vga or none? should be auto-detected, but can be overridden... */
472 static int display_type;
473 module_param(display_type, int, S_IRUGO);
474 MODULE_PARM_DESC(display_type, "Type of attached display. 0=autodetect, 1=vfd, 2=lcd, 3=vga, 4=none (default: autodetect)");
475 
476 static int pad_stabilize = 1;
477 module_param(pad_stabilize, int, S_IRUGO | S_IWUSR);
478 MODULE_PARM_DESC(pad_stabilize, "Apply stabilization algorithm to iMON PAD presses in arrow key mode. 0=disable, 1=enable (default).");
479 
480 /*
481  * In certain use cases, mouse mode isn't really helpful, and could actually
482  * cause confusion, so allow disabling it when the IR device is open.
483  */
484 static bool nomouse;
485 module_param(nomouse, bool, S_IRUGO | S_IWUSR);
486 MODULE_PARM_DESC(nomouse, "Disable mouse input device mode when IR device is open. 0=don't disable, 1=disable. (default: don't disable)");
487 
488 /* threshold at which a pad push registers as an arrow key in kbd mode */
489 static int pad_thresh;
490 module_param(pad_thresh, int, S_IRUGO | S_IWUSR);
491 MODULE_PARM_DESC(pad_thresh, "Threshold at which a pad push registers as an arrow key in kbd mode (default: 28)");
492 
493 
494 static void free_imon_context(struct imon_context *ictx)
495 {
496 	struct device *dev = ictx->dev;
497 
498 	usb_free_urb(ictx->tx_urb);
499 	WARN_ON(ictx->dev_present_intf0);
500 	usb_free_urb(ictx->rx_urb_intf0);
501 	WARN_ON(ictx->dev_present_intf1);
502 	usb_free_urb(ictx->rx_urb_intf1);
503 	kfree_rcu(ictx, rcu);
504 
505 	dev_dbg(dev, "%s: iMON context freed\n", __func__);
506 }
507 
508 /*
509  * Called when the Display device (e.g. /dev/lcd0)
510  * is opened by the application.
511  */
512 static int display_open(struct inode *inode, struct file *file)
513 {
514 	struct usb_interface *interface;
515 	struct imon_context *ictx = NULL;
516 	int subminor;
517 	int retval = 0;
518 
519 	subminor = iminor(inode);
520 	interface = usb_find_interface(&imon_driver, subminor);
521 	if (!interface) {
522 		pr_err("could not find interface for minor %d\n", subminor);
523 		retval = -ENODEV;
524 		goto exit;
525 	}
526 
527 	rcu_read_lock();
528 	ictx = usb_get_intfdata(interface);
529 	if (!ictx || ictx->disconnected || !refcount_inc_not_zero(&ictx->users)) {
530 		rcu_read_unlock();
531 		pr_err("no context found for minor %d\n", subminor);
532 		retval = -ENODEV;
533 		goto exit;
534 	}
535 	rcu_read_unlock();
536 
537 	mutex_lock(&ictx->lock);
538 
539 	if (!ictx->display_supported) {
540 		pr_err("display not supported by device\n");
541 		retval = -ENODEV;
542 	} else if (ictx->display_isopen) {
543 		pr_err("display port is already open\n");
544 		retval = -EBUSY;
545 	} else {
546 		ictx->display_isopen = true;
547 		file->private_data = ictx;
548 		dev_dbg(ictx->dev, "display port opened\n");
549 	}
550 
551 	mutex_unlock(&ictx->lock);
552 
553 	if (retval && refcount_dec_and_test(&ictx->users))
554 		free_imon_context(ictx);
555 
556 exit:
557 	return retval;
558 }
559 
560 /*
561  * Called when the display device (e.g. /dev/lcd0)
562  * is closed by the application.
563  */
564 static int display_close(struct inode *inode, struct file *file)
565 {
566 	struct imon_context *ictx = file->private_data;
567 	int retval = 0;
568 
569 	mutex_lock(&ictx->lock);
570 
571 	if (!ictx->display_supported) {
572 		pr_err("display not supported by device\n");
573 		retval = -ENODEV;
574 	} else if (!ictx->display_isopen) {
575 		pr_err("display is not open\n");
576 		retval = -EIO;
577 	} else {
578 		ictx->display_isopen = false;
579 		dev_dbg(ictx->dev, "display port closed\n");
580 	}
581 
582 	mutex_unlock(&ictx->lock);
583 	if (refcount_dec_and_test(&ictx->users))
584 		free_imon_context(ictx);
585 	return retval;
586 }
587 
588 /*
589  * Sends a packet to the device -- this function must be called with
590  * ictx->lock held, or its unlock/lock sequence while waiting for tx
591  * to complete can/will lead to a deadlock.
592  */
593 static int send_packet(struct imon_context *ictx)
594 {
595 	unsigned int pipe;
596 	unsigned long timeout;
597 	int interval = 0;
598 	int retval = 0;
599 	struct usb_ctrlrequest *control_req = NULL;
600 
601 	/* Check if we need to use control or interrupt urb */
602 	if (!ictx->tx_control) {
603 		pipe = usb_sndintpipe(ictx->usbdev_intf0,
604 				      ictx->tx_endpoint->bEndpointAddress);
605 		interval = ictx->tx_endpoint->bInterval;
606 
607 		usb_fill_int_urb(ictx->tx_urb, ictx->usbdev_intf0, pipe,
608 				 ictx->usb_tx_buf,
609 				 sizeof(ictx->usb_tx_buf),
610 				 usb_tx_callback, ictx, interval);
611 
612 		ictx->tx_urb->actual_length = 0;
613 	} else {
614 		/* fill request into kmalloc'ed space: */
615 		control_req = kmalloc(sizeof(*control_req), GFP_KERNEL);
616 		if (control_req == NULL)
617 			return -ENOMEM;
618 
619 		/* setup packet is '21 09 0200 0001 0008' */
620 		control_req->bRequestType = 0x21;
621 		control_req->bRequest = 0x09;
622 		control_req->wValue = cpu_to_le16(0x0200);
623 		control_req->wIndex = cpu_to_le16(0x0001);
624 		control_req->wLength = cpu_to_le16(0x0008);
625 
626 		/* control pipe is endpoint 0x00 */
627 		pipe = usb_sndctrlpipe(ictx->usbdev_intf0, 0);
628 
629 		/* build the control urb */
630 		usb_fill_control_urb(ictx->tx_urb, ictx->usbdev_intf0,
631 				     pipe, (unsigned char *)control_req,
632 				     ictx->usb_tx_buf,
633 				     sizeof(ictx->usb_tx_buf),
634 				     usb_tx_callback, ictx);
635 		ictx->tx_urb->actual_length = 0;
636 	}
637 
638 	reinit_completion(&ictx->tx.finished);
639 	ictx->tx.busy = true;
640 	smp_rmb(); /* ensure later readers know we're busy */
641 
642 	retval = usb_submit_urb(ictx->tx_urb, GFP_KERNEL);
643 	if (retval) {
644 		ictx->tx.busy = false;
645 		smp_rmb(); /* ensure later readers know we're not busy */
646 		pr_err_ratelimited("error submitting urb(%d)\n", retval);
647 	} else {
648 		/* Wait for transmission to complete (or abort) */
649 		retval = wait_for_completion_interruptible(
650 				&ictx->tx.finished);
651 		if (retval) {
652 			usb_kill_urb(ictx->tx_urb);
653 			pr_err_ratelimited("task interrupted\n");
654 		}
655 
656 		ictx->tx.busy = false;
657 		retval = ictx->tx.status;
658 		if (retval)
659 			pr_err_ratelimited("packet tx failed (%d)\n", retval);
660 	}
661 
662 	kfree(control_req);
663 
664 	/*
665 	 * Induce a mandatory delay before returning, as otherwise,
666 	 * send_packet can get called so rapidly as to overwhelm the device,
667 	 * particularly on faster systems and/or those with quirky usb.
668 	 */
669 	timeout = msecs_to_jiffies(ictx->send_packet_delay);
670 	set_current_state(TASK_INTERRUPTIBLE);
671 	schedule_timeout(timeout);
672 
673 	return retval;
674 }
675 
676 /*
677  * Sends an associate packet to the iMON 2.4G.
678  *
679  * This might not be such a good idea, since it has an id collision with
680  * some versions of the "IR & VFD" combo. The only way to determine if it
681  * is an RF version is to look at the product description string. (Which
682  * we currently do not fetch).
683  */
684 static int send_associate_24g(struct imon_context *ictx)
685 {
686 	const unsigned char packet[8] = { 0x01, 0x00, 0x00, 0x00,
687 					  0x00, 0x00, 0x00, 0x20 };
688 
689 	if (!ictx) {
690 		pr_err("no context for device\n");
691 		return -ENODEV;
692 	}
693 
694 	if (!ictx->dev_present_intf0) {
695 		pr_err("no iMON device present\n");
696 		return -ENODEV;
697 	}
698 
699 	memcpy(ictx->usb_tx_buf, packet, sizeof(packet));
700 
701 	return send_packet(ictx);
702 }
703 
704 /*
705  * Sends packets to setup and show clock on iMON display
706  *
707  * Arguments: year - last 2 digits of year, month - 1..12,
708  * day - 1..31, dow - day of the week (0-Sun...6-Sat),
709  * hour - 0..23, minute - 0..59, second - 0..59
710  */
711 static int send_set_imon_clock(struct imon_context *ictx,
712 			       unsigned int year, unsigned int month,
713 			       unsigned int day, unsigned int dow,
714 			       unsigned int hour, unsigned int minute,
715 			       unsigned int second)
716 {
717 	unsigned char clock_enable_pkt[IMON_CLOCK_ENABLE_PACKETS][8];
718 	int retval = 0;
719 	int i;
720 
721 	if (!ictx) {
722 		pr_err("no context for device\n");
723 		return -ENODEV;
724 	}
725 
726 	switch (ictx->display_type) {
727 	case IMON_DISPLAY_TYPE_LCD:
728 		clock_enable_pkt[0][0] = 0x80;
729 		clock_enable_pkt[0][1] = year;
730 		clock_enable_pkt[0][2] = month-1;
731 		clock_enable_pkt[0][3] = day;
732 		clock_enable_pkt[0][4] = hour;
733 		clock_enable_pkt[0][5] = minute;
734 		clock_enable_pkt[0][6] = second;
735 
736 		clock_enable_pkt[1][0] = 0x80;
737 		clock_enable_pkt[1][1] = 0;
738 		clock_enable_pkt[1][2] = 0;
739 		clock_enable_pkt[1][3] = 0;
740 		clock_enable_pkt[1][4] = 0;
741 		clock_enable_pkt[1][5] = 0;
742 		clock_enable_pkt[1][6] = 0;
743 
744 		if (ictx->product == 0xffdc) {
745 			clock_enable_pkt[0][7] = 0x50;
746 			clock_enable_pkt[1][7] = 0x51;
747 		} else {
748 			clock_enable_pkt[0][7] = 0x88;
749 			clock_enable_pkt[1][7] = 0x8a;
750 		}
751 
752 		break;
753 
754 	case IMON_DISPLAY_TYPE_VFD:
755 		clock_enable_pkt[0][0] = year;
756 		clock_enable_pkt[0][1] = month-1;
757 		clock_enable_pkt[0][2] = day;
758 		clock_enable_pkt[0][3] = dow;
759 		clock_enable_pkt[0][4] = hour;
760 		clock_enable_pkt[0][5] = minute;
761 		clock_enable_pkt[0][6] = second;
762 		clock_enable_pkt[0][7] = 0x40;
763 
764 		clock_enable_pkt[1][0] = 0;
765 		clock_enable_pkt[1][1] = 0;
766 		clock_enable_pkt[1][2] = 1;
767 		clock_enable_pkt[1][3] = 0;
768 		clock_enable_pkt[1][4] = 0;
769 		clock_enable_pkt[1][5] = 0;
770 		clock_enable_pkt[1][6] = 0;
771 		clock_enable_pkt[1][7] = 0x42;
772 
773 		break;
774 
775 	default:
776 		return -ENODEV;
777 	}
778 
779 	for (i = 0; i < IMON_CLOCK_ENABLE_PACKETS; i++) {
780 		memcpy(ictx->usb_tx_buf, clock_enable_pkt[i], 8);
781 		retval = send_packet(ictx);
782 		if (retval) {
783 			pr_err("send_packet failed for packet %d\n", i);
784 			break;
785 		}
786 	}
787 
788 	return retval;
789 }
790 
791 /*
792  * These are the sysfs functions to handle the association on the iMON 2.4G LT.
793  */
794 static ssize_t associate_remote_show(struct device *d,
795 				     struct device_attribute *attr,
796 				     char *buf)
797 {
798 	struct imon_context *ictx = dev_get_drvdata(d);
799 
800 	if (!ictx)
801 		return -ENODEV;
802 
803 	mutex_lock(&ictx->lock);
804 	if (ictx->rf_isassociating)
805 		strscpy(buf, "associating\n", PAGE_SIZE);
806 	else
807 		strscpy(buf, "closed\n", PAGE_SIZE);
808 
809 	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");
810 	mutex_unlock(&ictx->lock);
811 	return strlen(buf);
812 }
813 
814 static ssize_t associate_remote_store(struct device *d,
815 				      struct device_attribute *attr,
816 				      const char *buf, size_t count)
817 {
818 	struct imon_context *ictx;
819 
820 	ictx = dev_get_drvdata(d);
821 
822 	if (!ictx)
823 		return -ENODEV;
824 
825 	mutex_lock(&ictx->lock);
826 	ictx->rf_isassociating = true;
827 	send_associate_24g(ictx);
828 	mutex_unlock(&ictx->lock);
829 
830 	return count;
831 }
832 
833 /*
834  * sysfs functions to control internal imon clock
835  */
836 static ssize_t imon_clock_show(struct device *d,
837 			       struct device_attribute *attr, char *buf)
838 {
839 	struct imon_context *ictx = dev_get_drvdata(d);
840 	size_t len;
841 
842 	if (!ictx)
843 		return -ENODEV;
844 
845 	mutex_lock(&ictx->lock);
846 
847 	if (!ictx->display_supported) {
848 		len = sysfs_emit(buf, "Not supported.");
849 	} else {
850 		len = sysfs_emit(buf,
851 				 "To set the clock on your iMON display:\n"
852 				 "# date \"+%%y %%m %%d %%w %%H %%M %%S\" > imon_clock\n"
853 				 "%s", ictx->display_isopen ?
854 				 "\nNOTE: imon device must be closed\n" : "");
855 	}
856 
857 	mutex_unlock(&ictx->lock);
858 
859 	return len;
860 }
861 
862 static ssize_t imon_clock_store(struct device *d,
863 				struct device_attribute *attr,
864 				const char *buf, size_t count)
865 {
866 	struct imon_context *ictx = dev_get_drvdata(d);
867 	ssize_t retval;
868 	unsigned int year, month, day, dow, hour, minute, second;
869 
870 	if (!ictx)
871 		return -ENODEV;
872 
873 	mutex_lock(&ictx->lock);
874 
875 	if (!ictx->display_supported) {
876 		retval = -ENODEV;
877 		goto exit;
878 	} else if (ictx->display_isopen) {
879 		retval = -EBUSY;
880 		goto exit;
881 	}
882 
883 	if (sscanf(buf, "%u %u %u %u %u %u %u",	&year, &month, &day, &dow,
884 		   &hour, &minute, &second) != 7) {
885 		retval = -EINVAL;
886 		goto exit;
887 	}
888 
889 	if ((month < 1 || month > 12) ||
890 	    (day < 1 || day > 31) || (dow > 6) ||
891 	    (hour > 23) || (minute > 59) || (second > 59)) {
892 		retval = -EINVAL;
893 		goto exit;
894 	}
895 
896 	retval = send_set_imon_clock(ictx, year, month, day, dow,
897 				     hour, minute, second);
898 	if (retval)
899 		goto exit;
900 
901 	retval = count;
902 exit:
903 	mutex_unlock(&ictx->lock);
904 
905 	return retval;
906 }
907 
908 
909 static DEVICE_ATTR_RW(imon_clock);
910 static DEVICE_ATTR_RW(associate_remote);
911 
912 static struct attribute *imon_display_sysfs_entries[] = {
913 	&dev_attr_imon_clock.attr,
914 	NULL
915 };
916 
917 static const struct attribute_group imon_display_attr_group = {
918 	.attrs = imon_display_sysfs_entries
919 };
920 
921 static struct attribute *imon_rf_sysfs_entries[] = {
922 	&dev_attr_associate_remote.attr,
923 	NULL
924 };
925 
926 static const struct attribute_group imon_rf_attr_group = {
927 	.attrs = imon_rf_sysfs_entries
928 };
929 
930 /*
931  * Writes data to the VFD.  The iMON VFD is 2x16 characters
932  * and requires data in 5 consecutive USB interrupt packets,
933  * each packet but the last carrying 7 bytes.
934  *
935  * I don't know if the VFD board supports features such as
936  * scrolling, clearing rows, blanking, etc. so at
937  * the caller must provide a full screen of data.  If fewer
938  * than 32 bytes are provided spaces will be appended to
939  * generate a full screen.
940  */
941 static ssize_t vfd_write(struct file *file, const char __user *buf,
942 			 size_t n_bytes, loff_t *pos)
943 {
944 	int i;
945 	int offset;
946 	int seq;
947 	int retval = 0;
948 	struct imon_context *ictx = file->private_data;
949 	static const unsigned char vfd_packet6[] = {
950 		0x01, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF };
951 
952 	if (ictx->disconnected)
953 		return -ENODEV;
954 
955 	if (mutex_lock_interruptible(&ictx->lock))
956 		return -ERESTARTSYS;
957 
958 	if (!ictx->dev_present_intf0) {
959 		pr_err_ratelimited("no iMON device present\n");
960 		retval = -ENODEV;
961 		goto exit;
962 	}
963 
964 	if (n_bytes <= 0 || n_bytes > 32) {
965 		pr_err_ratelimited("invalid payload size\n");
966 		retval = -EINVAL;
967 		goto exit;
968 	}
969 
970 	if (copy_from_user(ictx->tx.data_buf, buf, n_bytes)) {
971 		retval = -EFAULT;
972 		goto exit;
973 	}
974 
975 	/* Pad with spaces */
976 	for (i = n_bytes; i < 32; ++i)
977 		ictx->tx.data_buf[i] = ' ';
978 
979 	for (i = 32; i < 35; ++i)
980 		ictx->tx.data_buf[i] = 0xFF;
981 
982 	offset = 0;
983 	seq = 0;
984 
985 	do {
986 		memcpy(ictx->usb_tx_buf, ictx->tx.data_buf + offset, 7);
987 		ictx->usb_tx_buf[7] = (unsigned char) seq;
988 
989 		retval = send_packet(ictx);
990 		if (retval) {
991 			pr_err_ratelimited("send packet #%d failed\n", seq / 2);
992 			goto exit;
993 		} else {
994 			seq += 2;
995 			offset += 7;
996 		}
997 
998 	} while (offset < 35);
999 
1000 	/* Send packet #6 */
1001 	memcpy(ictx->usb_tx_buf, &vfd_packet6, sizeof(vfd_packet6));
1002 	ictx->usb_tx_buf[7] = (unsigned char) seq;
1003 	retval = send_packet(ictx);
1004 	if (retval)
1005 		pr_err_ratelimited("send packet #%d failed\n", seq / 2);
1006 
1007 exit:
1008 	mutex_unlock(&ictx->lock);
1009 
1010 	return (!retval) ? n_bytes : retval;
1011 }
1012 
1013 /*
1014  * Writes data to the LCD.  The iMON OEM LCD screen expects 8-byte
1015  * packets. We accept data as 16 hexadecimal digits, followed by a
1016  * newline (to make it easy to drive the device from a command-line
1017  * -- even though the actual binary data is a bit complicated).
1018  *
1019  * The device itself is not a "traditional" text-mode display. It's
1020  * actually a 16x96 pixel bitmap display. That means if you want to
1021  * display text, you've got to have your own "font" and translate the
1022  * text into bitmaps for display. This is really flexible (you can
1023  * display whatever diacritics you need, and so on), but it's also
1024  * a lot more complicated than most LCDs...
1025  */
1026 static ssize_t lcd_write(struct file *file, const char __user *buf,
1027 			 size_t n_bytes, loff_t *pos)
1028 {
1029 	int retval = 0;
1030 	struct imon_context *ictx = file->private_data;
1031 
1032 	if (ictx->disconnected)
1033 		return -ENODEV;
1034 
1035 	mutex_lock(&ictx->lock);
1036 
1037 	if (!ictx->display_supported) {
1038 		pr_err_ratelimited("no iMON display present\n");
1039 		retval = -ENODEV;
1040 		goto exit;
1041 	}
1042 
1043 	if (n_bytes != 8) {
1044 		pr_err_ratelimited("invalid payload size: %d (expected 8)\n",
1045 				   (int)n_bytes);
1046 		retval = -EINVAL;
1047 		goto exit;
1048 	}
1049 
1050 	if (copy_from_user(ictx->usb_tx_buf, buf, 8)) {
1051 		retval = -EFAULT;
1052 		goto exit;
1053 	}
1054 
1055 	retval = send_packet(ictx);
1056 	if (retval) {
1057 		pr_err_ratelimited("send packet failed!\n");
1058 		goto exit;
1059 	} else {
1060 		dev_dbg(ictx->dev, "%s: write %d bytes to LCD\n",
1061 			__func__, (int) n_bytes);
1062 	}
1063 exit:
1064 	mutex_unlock(&ictx->lock);
1065 	return (!retval) ? n_bytes : retval;
1066 }
1067 
1068 /*
1069  * Callback function for USB core API: transmit data
1070  */
1071 static void usb_tx_callback(struct urb *urb)
1072 {
1073 	struct imon_context *ictx;
1074 
1075 	if (!urb)
1076 		return;
1077 	ictx = (struct imon_context *)urb->context;
1078 	if (!ictx)
1079 		return;
1080 
1081 	ictx->tx.status = urb->status;
1082 
1083 	/* notify waiters that write has finished */
1084 	ictx->tx.busy = false;
1085 	smp_rmb(); /* ensure later readers know we're not busy */
1086 	complete(&ictx->tx.finished);
1087 }
1088 
1089 /*
1090  * report touchscreen input
1091  */
1092 static void imon_touch_display_timeout(struct timer_list *t)
1093 {
1094 	struct imon_context *ictx = from_timer(ictx, t, ttimer);
1095 
1096 	if (ictx->display_type != IMON_DISPLAY_TYPE_VGA)
1097 		return;
1098 
1099 	input_report_abs(ictx->touch, ABS_X, ictx->touch_x);
1100 	input_report_abs(ictx->touch, ABS_Y, ictx->touch_y);
1101 	input_report_key(ictx->touch, BTN_TOUCH, 0x00);
1102 	input_sync(ictx->touch);
1103 }
1104 
1105 /*
1106  * iMON IR receivers support two different signal sets -- those used by
1107  * the iMON remotes, and those used by the Windows MCE remotes (which is
1108  * really just RC-6), but only one or the other at a time, as the signals
1109  * are decoded onboard the receiver.
1110  *
1111  * This function gets called two different ways, one way is from
1112  * rc_register_device, for initial protocol selection/setup, and the other is
1113  * via a userspace-initiated protocol change request, either by direct sysfs
1114  * prodding or by something like ir-keytable. In the rc_register_device case,
1115  * the imon context lock is already held, but when initiated from userspace,
1116  * it is not, so we must acquire it prior to calling send_packet, which
1117  * requires that the lock is held.
1118  */
1119 static int imon_ir_change_protocol(struct rc_dev *rc, u64 *rc_proto)
1120 {
1121 	int retval;
1122 	struct imon_context *ictx = rc->priv;
1123 	struct device *dev = ictx->dev;
1124 	bool unlock = false;
1125 	unsigned char ir_proto_packet[] = {
1126 		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x86 };
1127 
1128 	if (*rc_proto && !(*rc_proto & rc->allowed_protocols))
1129 		dev_warn(dev, "Looks like you're trying to use an IR protocol this device does not support\n");
1130 
1131 	if (*rc_proto & RC_PROTO_BIT_RC6_MCE) {
1132 		dev_dbg(dev, "Configuring IR receiver for MCE protocol\n");
1133 		ir_proto_packet[0] = 0x01;
1134 		*rc_proto = RC_PROTO_BIT_RC6_MCE;
1135 	} else if (*rc_proto & RC_PROTO_BIT_IMON) {
1136 		dev_dbg(dev, "Configuring IR receiver for iMON protocol\n");
1137 		if (!pad_stabilize)
1138 			dev_dbg(dev, "PAD stabilize functionality disabled\n");
1139 		/* ir_proto_packet[0] = 0x00; // already the default */
1140 		*rc_proto = RC_PROTO_BIT_IMON;
1141 	} else {
1142 		dev_warn(dev, "Unsupported IR protocol specified, overriding to iMON IR protocol\n");
1143 		if (!pad_stabilize)
1144 			dev_dbg(dev, "PAD stabilize functionality disabled\n");
1145 		/* ir_proto_packet[0] = 0x00; // already the default */
1146 		*rc_proto = RC_PROTO_BIT_IMON;
1147 	}
1148 
1149 	memcpy(ictx->usb_tx_buf, &ir_proto_packet, sizeof(ir_proto_packet));
1150 
1151 	unlock = mutex_trylock(&ictx->lock);
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 	ictx->usbdev_intf1 = NULL;
2365 	mutex_unlock(&ictx->lock);
2366 	usb_free_urb(rx_urb);
2367 	ictx->rx_urb_intf1 = NULL;
2368 rx_urb_alloc_failed:
2369 	dev_err(ictx->dev, "unable to initialize intf1, err %d\n", ret);
2370 
2371 	return NULL;
2372 }
2373 
2374 static void imon_init_display(struct imon_context *ictx,
2375 			      struct usb_interface *intf)
2376 {
2377 	int ret;
2378 
2379 	dev_dbg(ictx->dev, "Registering iMON display with sysfs\n");
2380 
2381 	/* set up sysfs entry for built-in clock */
2382 	ret = sysfs_create_group(&intf->dev.kobj, &imon_display_attr_group);
2383 	if (ret)
2384 		dev_err(ictx->dev, "Could not create display sysfs entries(%d)",
2385 			ret);
2386 
2387 	if (ictx->display_type == IMON_DISPLAY_TYPE_LCD)
2388 		ret = usb_register_dev(intf, &imon_lcd_class);
2389 	else
2390 		ret = usb_register_dev(intf, &imon_vfd_class);
2391 	if (ret)
2392 		/* Not a fatal error, so ignore */
2393 		dev_info(ictx->dev, "could not get a minor number for display\n");
2394 
2395 }
2396 
2397 /*
2398  * Callback function for USB core API: Probe
2399  */
2400 static int imon_probe(struct usb_interface *interface,
2401 		      const struct usb_device_id *id)
2402 {
2403 	struct usb_device *usbdev = NULL;
2404 	struct usb_host_interface *iface_desc = NULL;
2405 	struct usb_interface *first_if;
2406 	struct device *dev = &interface->dev;
2407 	int ifnum, sysfs_err;
2408 	int ret = 0;
2409 	struct imon_context *ictx = NULL;
2410 	u16 vendor, product;
2411 
2412 	usbdev     = usb_get_dev(interface_to_usbdev(interface));
2413 	iface_desc = interface->cur_altsetting;
2414 	ifnum      = iface_desc->desc.bInterfaceNumber;
2415 	vendor     = le16_to_cpu(usbdev->descriptor.idVendor);
2416 	product    = le16_to_cpu(usbdev->descriptor.idProduct);
2417 
2418 	dev_dbg(dev, "%s: found iMON device (%04x:%04x, intf%d)\n",
2419 		__func__, vendor, product, ifnum);
2420 
2421 	first_if = usb_ifnum_to_if(usbdev, 0);
2422 	if (!first_if) {
2423 		ret = -ENODEV;
2424 		goto fail;
2425 	}
2426 
2427 	if (first_if->dev.driver != interface->dev.driver) {
2428 		dev_err(&interface->dev, "inconsistent driver matching\n");
2429 		ret = -EINVAL;
2430 		goto fail;
2431 	}
2432 
2433 	if (ifnum == 0) {
2434 		ictx = imon_init_intf0(interface, id);
2435 		if (!ictx) {
2436 			pr_err("failed to initialize context!\n");
2437 			ret = -ENODEV;
2438 			goto fail;
2439 		}
2440 		refcount_set(&ictx->users, 1);
2441 
2442 	} else {
2443 		/* this is the secondary interface on the device */
2444 		struct imon_context *first_if_ctx = usb_get_intfdata(first_if);
2445 
2446 		/* fail early if first intf failed to register */
2447 		if (!first_if_ctx) {
2448 			ret = -ENODEV;
2449 			goto fail;
2450 		}
2451 
2452 		ictx = imon_init_intf1(interface, first_if_ctx);
2453 		if (!ictx) {
2454 			pr_err("failed to attach to context!\n");
2455 			ret = -ENODEV;
2456 			goto fail;
2457 		}
2458 		refcount_inc(&ictx->users);
2459 
2460 	}
2461 
2462 	usb_set_intfdata(interface, ictx);
2463 
2464 	if (ifnum == 0) {
2465 		if (product == 0xffdc && ictx->rf_device) {
2466 			sysfs_err = sysfs_create_group(&interface->dev.kobj,
2467 						       &imon_rf_attr_group);
2468 			if (sysfs_err)
2469 				pr_err("Could not create RF sysfs entries(%d)\n",
2470 				       sysfs_err);
2471 		}
2472 
2473 		if (ictx->display_supported)
2474 			imon_init_display(ictx, interface);
2475 	}
2476 
2477 	dev_info(dev, "iMON device (%04x:%04x, intf%d) on usb<%d:%d> initialized\n",
2478 		 vendor, product, ifnum,
2479 		 usbdev->bus->busnum, usbdev->devnum);
2480 
2481 	usb_put_dev(usbdev);
2482 
2483 	return 0;
2484 
2485 fail:
2486 	usb_put_dev(usbdev);
2487 	dev_err(dev, "unable to register, err %d\n", ret);
2488 
2489 	return ret;
2490 }
2491 
2492 /*
2493  * Callback function for USB core API: disconnect
2494  */
2495 static void imon_disconnect(struct usb_interface *interface)
2496 {
2497 	struct imon_context *ictx;
2498 	struct device *dev;
2499 	int ifnum;
2500 
2501 	ictx = usb_get_intfdata(interface);
2502 	ictx->disconnected = true;
2503 	dev = ictx->dev;
2504 	ifnum = interface->cur_altsetting->desc.bInterfaceNumber;
2505 
2506 	/*
2507 	 * sysfs_remove_group is safe to call even if sysfs_create_group
2508 	 * hasn't been called
2509 	 */
2510 	sysfs_remove_group(&interface->dev.kobj, &imon_display_attr_group);
2511 	sysfs_remove_group(&interface->dev.kobj, &imon_rf_attr_group);
2512 
2513 	usb_set_intfdata(interface, NULL);
2514 
2515 	/* Abort ongoing write */
2516 	if (ictx->tx.busy) {
2517 		usb_kill_urb(ictx->tx_urb);
2518 		complete(&ictx->tx.finished);
2519 	}
2520 
2521 	if (ifnum == 0) {
2522 		ictx->dev_present_intf0 = false;
2523 		usb_kill_urb(ictx->rx_urb_intf0);
2524 		input_unregister_device(ictx->idev);
2525 		rc_unregister_device(ictx->rdev);
2526 		if (ictx->display_supported) {
2527 			if (ictx->display_type == IMON_DISPLAY_TYPE_LCD)
2528 				usb_deregister_dev(interface, &imon_lcd_class);
2529 			else if (ictx->display_type == IMON_DISPLAY_TYPE_VFD)
2530 				usb_deregister_dev(interface, &imon_vfd_class);
2531 		}
2532 		usb_put_dev(ictx->usbdev_intf0);
2533 	} else {
2534 		ictx->dev_present_intf1 = false;
2535 		usb_kill_urb(ictx->rx_urb_intf1);
2536 		if (ictx->display_type == IMON_DISPLAY_TYPE_VGA) {
2537 			del_timer_sync(&ictx->ttimer);
2538 			input_unregister_device(ictx->touch);
2539 		}
2540 		usb_put_dev(ictx->usbdev_intf1);
2541 	}
2542 
2543 	if (refcount_dec_and_test(&ictx->users))
2544 		free_imon_context(ictx);
2545 
2546 	dev_dbg(dev, "%s: iMON device (intf%d) disconnected\n",
2547 		__func__, ifnum);
2548 }
2549 
2550 static int imon_suspend(struct usb_interface *intf, pm_message_t message)
2551 {
2552 	struct imon_context *ictx = usb_get_intfdata(intf);
2553 	int ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
2554 
2555 	if (ifnum == 0)
2556 		usb_kill_urb(ictx->rx_urb_intf0);
2557 	else
2558 		usb_kill_urb(ictx->rx_urb_intf1);
2559 
2560 	return 0;
2561 }
2562 
2563 static int imon_resume(struct usb_interface *intf)
2564 {
2565 	int rc = 0;
2566 	struct imon_context *ictx = usb_get_intfdata(intf);
2567 	int ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
2568 
2569 	if (ifnum == 0) {
2570 		usb_fill_int_urb(ictx->rx_urb_intf0, ictx->usbdev_intf0,
2571 			usb_rcvintpipe(ictx->usbdev_intf0,
2572 				ictx->rx_endpoint_intf0->bEndpointAddress),
2573 			ictx->usb_rx_buf, sizeof(ictx->usb_rx_buf),
2574 			usb_rx_callback_intf0, ictx,
2575 			ictx->rx_endpoint_intf0->bInterval);
2576 
2577 		rc = usb_submit_urb(ictx->rx_urb_intf0, GFP_NOIO);
2578 
2579 	} else {
2580 		usb_fill_int_urb(ictx->rx_urb_intf1, ictx->usbdev_intf1,
2581 			usb_rcvintpipe(ictx->usbdev_intf1,
2582 				ictx->rx_endpoint_intf1->bEndpointAddress),
2583 			ictx->usb_rx_buf, sizeof(ictx->usb_rx_buf),
2584 			usb_rx_callback_intf1, ictx,
2585 			ictx->rx_endpoint_intf1->bInterval);
2586 
2587 		rc = usb_submit_urb(ictx->rx_urb_intf1, GFP_NOIO);
2588 	}
2589 
2590 	return rc;
2591 }
2592 
2593 module_usb_driver(imon_driver);
2594