1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Front panel driver for Linux
4 * Copyright (C) 2000-2008, Willy Tarreau <w@1wt.eu>
5 * Copyright (C) 2016-2017 Glider bvba
6 *
7 * This code drives an LCD module (/dev/lcd), and a keypad (/dev/keypad)
8 * connected to a parallel printer port.
9 *
10 * The LCD module may either be an HD44780-like 8-bit parallel LCD, or a 1-bit
11 * serial module compatible with Samsung's KS0074. The pins may be connected in
12 * any combination, everything is programmable.
13 *
14 * The keypad consists in a matrix of push buttons connecting input pins to
15 * data output pins or to the ground. The combinations have to be hard-coded
16 * in the driver, though several profiles exist and adding new ones is easy.
17 *
18 * Several profiles are provided for commonly found LCD+keypad modules on the
19 * market, such as those found in Nexcom's appliances.
20 *
21 * FIXME:
22 *      - the initialization/deinitialization process is very dirty and should
23 *        be rewritten. It may even be buggy.
24 *
25 * TODO:
26 *	- document 24 keys keyboard (3 rows of 8 cols, 32 diodes + 2 inputs)
27 *      - make the LCD a part of a virtual screen of Vx*Vy
28 *	- make the inputs list smp-safe
29 *      - change the keyboard to a double mapping : signals -> key_id -> values
30 *        so that applications can change values without knowing signals
31 *
32 */
33
34#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
35
36#include <linux/module.h>
37
38#include <linux/types.h>
39#include <linux/errno.h>
40#include <linux/signal.h>
41#include <linux/sched.h>
42#include <linux/spinlock.h>
43#include <linux/interrupt.h>
44#include <linux/miscdevice.h>
45#include <linux/slab.h>
46#include <linux/ioport.h>
47#include <linux/fcntl.h>
48#include <linux/init.h>
49#include <linux/delay.h>
50#include <linux/kernel.h>
51#include <linux/ctype.h>
52#include <linux/parport.h>
53#include <linux/list.h>
54
55#include <linux/io.h>
56#include <linux/uaccess.h>
57
58#include "charlcd.h"
59#include "hd44780_common.h"
60
61#define LCD_MAXBYTES		256	/* max burst write */
62
63#define KEYPAD_BUFFER		64
64
65/* poll the keyboard this every second */
66#define INPUT_POLL_TIME		(HZ / 50)
67/* a key starts to repeat after this times INPUT_POLL_TIME */
68#define KEYPAD_REP_START	(10)
69/* a key repeats this times INPUT_POLL_TIME */
70#define KEYPAD_REP_DELAY	(2)
71
72/* converts an r_str() input to an active high, bits string : 000BAOSE */
73#define PNL_PINPUT(a)		((((unsigned char)(a)) ^ 0x7F) >> 3)
74
75#define PNL_PBUSY		0x80	/* inverted input, active low */
76#define PNL_PACK		0x40	/* direct input, active low */
77#define PNL_POUTPA		0x20	/* direct input, active high */
78#define PNL_PSELECD		0x10	/* direct input, active high */
79#define PNL_PERRORP		0x08	/* direct input, active low */
80
81#define PNL_PBIDIR		0x20	/* bi-directional ports */
82/* high to read data in or-ed with data out */
83#define PNL_PINTEN		0x10
84#define PNL_PSELECP		0x08	/* inverted output, active low */
85#define PNL_PINITP		0x04	/* direct output, active low */
86#define PNL_PAUTOLF		0x02	/* inverted output, active low */
87#define PNL_PSTROBE		0x01	/* inverted output */
88
89#define PNL_PD0			0x01
90#define PNL_PD1			0x02
91#define PNL_PD2			0x04
92#define PNL_PD3			0x08
93#define PNL_PD4			0x10
94#define PNL_PD5			0x20
95#define PNL_PD6			0x40
96#define PNL_PD7			0x80
97
98#define PIN_NONE		0
99#define PIN_STROBE		1
100#define PIN_D0			2
101#define PIN_D1			3
102#define PIN_D2			4
103#define PIN_D3			5
104#define PIN_D4			6
105#define PIN_D5			7
106#define PIN_D6			8
107#define PIN_D7			9
108#define PIN_AUTOLF		14
109#define PIN_INITP		16
110#define PIN_SELECP		17
111#define PIN_NOT_SET		127
112
113#define NOT_SET			-1
114
115/* macros to simplify use of the parallel port */
116#define r_ctr(x)        (parport_read_control((x)->port))
117#define r_dtr(x)        (parport_read_data((x)->port))
118#define r_str(x)        (parport_read_status((x)->port))
119#define w_ctr(x, y)     (parport_write_control((x)->port, (y)))
120#define w_dtr(x, y)     (parport_write_data((x)->port, (y)))
121
122/* this defines which bits are to be used and which ones to be ignored */
123/* logical or of the output bits involved in the scan matrix */
124static __u8 scan_mask_o;
125/* logical or of the input bits involved in the scan matrix */
126static __u8 scan_mask_i;
127
128enum input_type {
129	INPUT_TYPE_STD,
130	INPUT_TYPE_KBD,
131};
132
133enum input_state {
134	INPUT_ST_LOW,
135	INPUT_ST_RISING,
136	INPUT_ST_HIGH,
137	INPUT_ST_FALLING,
138};
139
140struct logical_input {
141	struct list_head list;
142	__u64 mask;
143	__u64 value;
144	enum input_type type;
145	enum input_state state;
146	__u8 rise_time, fall_time;
147	__u8 rise_timer, fall_timer, high_timer;
148
149	union {
150		struct {	/* valid when type == INPUT_TYPE_STD */
151			void (*press_fct)(int);
152			void (*release_fct)(int);
153			int press_data;
154			int release_data;
155		} std;
156		struct {	/* valid when type == INPUT_TYPE_KBD */
157			char press_str[sizeof(void *) + sizeof(int)] __nonstring;
158			char repeat_str[sizeof(void *) + sizeof(int)] __nonstring;
159			char release_str[sizeof(void *) + sizeof(int)] __nonstring;
160		} kbd;
161	} u;
162};
163
164static LIST_HEAD(logical_inputs);	/* list of all defined logical inputs */
165
166/* physical contacts history
167 * Physical contacts are a 45 bits string of 9 groups of 5 bits each.
168 * The 8 lower groups correspond to output bits 0 to 7, and the 9th group
169 * corresponds to the ground.
170 * Within each group, bits are stored in the same order as read on the port :
171 * BAPSE (busy=4, ack=3, paper empty=2, select=1, error=0).
172 * So, each __u64 is represented like this :
173 * 0000000000000000000BAPSEBAPSEBAPSEBAPSEBAPSEBAPSEBAPSEBAPSEBAPSE
174 * <-----unused------><gnd><d07><d06><d05><d04><d03><d02><d01><d00>
175 */
176
177/* what has just been read from the I/O ports */
178static __u64 phys_read;
179/* previous phys_read */
180static __u64 phys_read_prev;
181/* stabilized phys_read (phys_read|phys_read_prev) */
182static __u64 phys_curr;
183/* previous phys_curr */
184static __u64 phys_prev;
185/* 0 means that at least one logical signal needs be computed */
186static char inputs_stable;
187
188/* these variables are specific to the keypad */
189static struct {
190	bool enabled;
191} keypad;
192
193static char keypad_buffer[KEYPAD_BUFFER];
194static int keypad_buflen;
195static int keypad_start;
196static char keypressed;
197static wait_queue_head_t keypad_read_wait;
198
199/* lcd-specific variables */
200static struct {
201	bool enabled;
202	bool initialized;
203
204	int charset;
205	int proto;
206
207	/* TODO: use union here? */
208	struct {
209		int e;
210		int rs;
211		int rw;
212		int cl;
213		int da;
214		int bl;
215	} pins;
216
217	struct charlcd *charlcd;
218} lcd;
219
220/* Needed only for init */
221static int selected_lcd_type = NOT_SET;
222
223/*
224 * Bit masks to convert LCD signals to parallel port outputs.
225 * _d_ are values for data port, _c_ are for control port.
226 * [0] = signal OFF, [1] = signal ON, [2] = mask
227 */
228#define BIT_CLR		0
229#define BIT_SET		1
230#define BIT_MSK		2
231#define BIT_STATES	3
232/*
233 * one entry for each bit on the LCD
234 */
235#define LCD_BIT_E	0
236#define LCD_BIT_RS	1
237#define LCD_BIT_RW	2
238#define LCD_BIT_BL	3
239#define LCD_BIT_CL	4
240#define LCD_BIT_DA	5
241#define LCD_BITS	6
242
243/*
244 * each bit can be either connected to a DATA or CTRL port
245 */
246#define LCD_PORT_C	0
247#define LCD_PORT_D	1
248#define LCD_PORTS	2
249
250static unsigned char lcd_bits[LCD_PORTS][LCD_BITS][BIT_STATES];
251
252/*
253 * LCD protocols
254 */
255#define LCD_PROTO_PARALLEL      0
256#define LCD_PROTO_SERIAL        1
257#define LCD_PROTO_TI_DA8XX_LCD	2
258
259/*
260 * LCD character sets
261 */
262#define LCD_CHARSET_NORMAL      0
263#define LCD_CHARSET_KS0074      1
264
265/*
266 * LCD types
267 */
268#define LCD_TYPE_NONE		0
269#define LCD_TYPE_CUSTOM		1
270#define LCD_TYPE_OLD		2
271#define LCD_TYPE_KS0074		3
272#define LCD_TYPE_HANTRONIX	4
273#define LCD_TYPE_NEXCOM		5
274
275/*
276 * keypad types
277 */
278#define KEYPAD_TYPE_NONE	0
279#define KEYPAD_TYPE_OLD		1
280#define KEYPAD_TYPE_NEW		2
281#define KEYPAD_TYPE_NEXCOM	3
282
283/*
284 * panel profiles
285 */
286#define PANEL_PROFILE_CUSTOM	0
287#define PANEL_PROFILE_OLD	1
288#define PANEL_PROFILE_NEW	2
289#define PANEL_PROFILE_HANTRONIX	3
290#define PANEL_PROFILE_NEXCOM	4
291#define PANEL_PROFILE_LARGE	5
292
293/*
294 * Construct custom config from the kernel's configuration
295 */
296#define DEFAULT_PARPORT         0
297#define DEFAULT_PROFILE         PANEL_PROFILE_LARGE
298#define DEFAULT_KEYPAD_TYPE     KEYPAD_TYPE_OLD
299#define DEFAULT_LCD_TYPE        LCD_TYPE_OLD
300#define DEFAULT_LCD_HEIGHT      2
301#define DEFAULT_LCD_WIDTH       40
302#define DEFAULT_LCD_CHARSET     LCD_CHARSET_NORMAL
303#define DEFAULT_LCD_PROTO       LCD_PROTO_PARALLEL
304
305#define DEFAULT_LCD_PIN_E       PIN_AUTOLF
306#define DEFAULT_LCD_PIN_RS      PIN_SELECP
307#define DEFAULT_LCD_PIN_RW      PIN_INITP
308#define DEFAULT_LCD_PIN_SCL     PIN_STROBE
309#define DEFAULT_LCD_PIN_SDA     PIN_D0
310#define DEFAULT_LCD_PIN_BL      PIN_NOT_SET
311
312#ifdef CONFIG_PANEL_PARPORT
313#undef DEFAULT_PARPORT
314#define DEFAULT_PARPORT CONFIG_PANEL_PARPORT
315#endif
316
317#ifdef CONFIG_PANEL_PROFILE
318#undef DEFAULT_PROFILE
319#define DEFAULT_PROFILE CONFIG_PANEL_PROFILE
320#endif
321
322#if DEFAULT_PROFILE == 0	/* custom */
323#ifdef CONFIG_PANEL_KEYPAD
324#undef DEFAULT_KEYPAD_TYPE
325#define DEFAULT_KEYPAD_TYPE CONFIG_PANEL_KEYPAD
326#endif
327
328#ifdef CONFIG_PANEL_LCD
329#undef DEFAULT_LCD_TYPE
330#define DEFAULT_LCD_TYPE CONFIG_PANEL_LCD
331#endif
332
333#ifdef CONFIG_PANEL_LCD_HEIGHT
334#undef DEFAULT_LCD_HEIGHT
335#define DEFAULT_LCD_HEIGHT CONFIG_PANEL_LCD_HEIGHT
336#endif
337
338#ifdef CONFIG_PANEL_LCD_WIDTH
339#undef DEFAULT_LCD_WIDTH
340#define DEFAULT_LCD_WIDTH CONFIG_PANEL_LCD_WIDTH
341#endif
342
343#ifdef CONFIG_PANEL_LCD_BWIDTH
344#undef DEFAULT_LCD_BWIDTH
345#define DEFAULT_LCD_BWIDTH CONFIG_PANEL_LCD_BWIDTH
346#endif
347
348#ifdef CONFIG_PANEL_LCD_HWIDTH
349#undef DEFAULT_LCD_HWIDTH
350#define DEFAULT_LCD_HWIDTH CONFIG_PANEL_LCD_HWIDTH
351#endif
352
353#ifdef CONFIG_PANEL_LCD_CHARSET
354#undef DEFAULT_LCD_CHARSET
355#define DEFAULT_LCD_CHARSET CONFIG_PANEL_LCD_CHARSET
356#endif
357
358#ifdef CONFIG_PANEL_LCD_PROTO
359#undef DEFAULT_LCD_PROTO
360#define DEFAULT_LCD_PROTO CONFIG_PANEL_LCD_PROTO
361#endif
362
363#ifdef CONFIG_PANEL_LCD_PIN_E
364#undef DEFAULT_LCD_PIN_E
365#define DEFAULT_LCD_PIN_E CONFIG_PANEL_LCD_PIN_E
366#endif
367
368#ifdef CONFIG_PANEL_LCD_PIN_RS
369#undef DEFAULT_LCD_PIN_RS
370#define DEFAULT_LCD_PIN_RS CONFIG_PANEL_LCD_PIN_RS
371#endif
372
373#ifdef CONFIG_PANEL_LCD_PIN_RW
374#undef DEFAULT_LCD_PIN_RW
375#define DEFAULT_LCD_PIN_RW CONFIG_PANEL_LCD_PIN_RW
376#endif
377
378#ifdef CONFIG_PANEL_LCD_PIN_SCL
379#undef DEFAULT_LCD_PIN_SCL
380#define DEFAULT_LCD_PIN_SCL CONFIG_PANEL_LCD_PIN_SCL
381#endif
382
383#ifdef CONFIG_PANEL_LCD_PIN_SDA
384#undef DEFAULT_LCD_PIN_SDA
385#define DEFAULT_LCD_PIN_SDA CONFIG_PANEL_LCD_PIN_SDA
386#endif
387
388#ifdef CONFIG_PANEL_LCD_PIN_BL
389#undef DEFAULT_LCD_PIN_BL
390#define DEFAULT_LCD_PIN_BL CONFIG_PANEL_LCD_PIN_BL
391#endif
392
393#endif /* DEFAULT_PROFILE == 0 */
394
395/* global variables */
396
397/* Device single-open policy control */
398static atomic_t keypad_available = ATOMIC_INIT(1);
399
400static struct pardevice *pprt;
401
402static int keypad_initialized;
403
404static DEFINE_SPINLOCK(pprt_lock);
405static struct timer_list scan_timer;
406
407MODULE_DESCRIPTION("Generic parallel port LCD/Keypad driver");
408
409static int parport = DEFAULT_PARPORT;
410module_param(parport, int, 0000);
411MODULE_PARM_DESC(parport, "Parallel port index (0=lpt1, 1=lpt2, ...)");
412
413static int profile = DEFAULT_PROFILE;
414module_param(profile, int, 0000);
415MODULE_PARM_DESC(profile,
416		 "1=16x2 old kp; 2=serial 16x2, new kp; 3=16x2 hantronix; "
417		 "4=16x2 nexcom; default=40x2, old kp");
418
419static int keypad_type = NOT_SET;
420module_param(keypad_type, int, 0000);
421MODULE_PARM_DESC(keypad_type,
422		 "Keypad type: 0=none, 1=old 6 keys, 2=new 6+1 keys, 3=nexcom 4 keys");
423
424static int lcd_type = NOT_SET;
425module_param(lcd_type, int, 0000);
426MODULE_PARM_DESC(lcd_type,
427		 "LCD type: 0=none, 1=compiled-in, 2=old, 3=serial ks0074, 4=hantronix, 5=nexcom");
428
429static int lcd_height = NOT_SET;
430module_param(lcd_height, int, 0000);
431MODULE_PARM_DESC(lcd_height, "Number of lines on the LCD");
432
433static int lcd_width = NOT_SET;
434module_param(lcd_width, int, 0000);
435MODULE_PARM_DESC(lcd_width, "Number of columns on the LCD");
436
437static int lcd_bwidth = NOT_SET;	/* internal buffer width (usually 40) */
438module_param(lcd_bwidth, int, 0000);
439MODULE_PARM_DESC(lcd_bwidth, "Internal LCD line width (40)");
440
441static int lcd_hwidth = NOT_SET;	/* hardware buffer width (usually 64) */
442module_param(lcd_hwidth, int, 0000);
443MODULE_PARM_DESC(lcd_hwidth, "LCD line hardware address (64)");
444
445static int lcd_charset = NOT_SET;
446module_param(lcd_charset, int, 0000);
447MODULE_PARM_DESC(lcd_charset, "LCD character set: 0=standard, 1=KS0074");
448
449static int lcd_proto = NOT_SET;
450module_param(lcd_proto, int, 0000);
451MODULE_PARM_DESC(lcd_proto,
452		 "LCD communication: 0=parallel (//), 1=serial, 2=TI LCD Interface");
453
454/*
455 * These are the parallel port pins the LCD control signals are connected to.
456 * Set this to 0 if the signal is not used. Set it to its opposite value
457 * (negative) if the signal is negated. -MAXINT is used to indicate that the
458 * pin has not been explicitly specified.
459 *
460 * WARNING! no check will be performed about collisions with keypad !
461 */
462
463static int lcd_e_pin  = PIN_NOT_SET;
464module_param(lcd_e_pin, int, 0000);
465MODULE_PARM_DESC(lcd_e_pin,
466		 "# of the // port pin connected to LCD 'E' signal, with polarity (-17..17)");
467
468static int lcd_rs_pin = PIN_NOT_SET;
469module_param(lcd_rs_pin, int, 0000);
470MODULE_PARM_DESC(lcd_rs_pin,
471		 "# of the // port pin connected to LCD 'RS' signal, with polarity (-17..17)");
472
473static int lcd_rw_pin = PIN_NOT_SET;
474module_param(lcd_rw_pin, int, 0000);
475MODULE_PARM_DESC(lcd_rw_pin,
476		 "# of the // port pin connected to LCD 'RW' signal, with polarity (-17..17)");
477
478static int lcd_cl_pin = PIN_NOT_SET;
479module_param(lcd_cl_pin, int, 0000);
480MODULE_PARM_DESC(lcd_cl_pin,
481		 "# of the // port pin connected to serial LCD 'SCL' signal, with polarity (-17..17)");
482
483static int lcd_da_pin = PIN_NOT_SET;
484module_param(lcd_da_pin, int, 0000);
485MODULE_PARM_DESC(lcd_da_pin,
486		 "# of the // port pin connected to serial LCD 'SDA' signal, with polarity (-17..17)");
487
488static int lcd_bl_pin = PIN_NOT_SET;
489module_param(lcd_bl_pin, int, 0000);
490MODULE_PARM_DESC(lcd_bl_pin,
491		 "# of the // port pin connected to LCD backlight, with polarity (-17..17)");
492
493/* Deprecated module parameters - consider not using them anymore */
494
495static int lcd_enabled = NOT_SET;
496module_param(lcd_enabled, int, 0000);
497MODULE_PARM_DESC(lcd_enabled, "Deprecated option, use lcd_type instead");
498
499static int keypad_enabled = NOT_SET;
500module_param(keypad_enabled, int, 0000);
501MODULE_PARM_DESC(keypad_enabled, "Deprecated option, use keypad_type instead");
502
503/* for some LCD drivers (ks0074) we need a charset conversion table. */
504static const unsigned char lcd_char_conv_ks0074[256] = {
505	/*          0|8   1|9   2|A   3|B   4|C   5|D   6|E   7|F */
506	/* 0x00 */ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
507	/* 0x08 */ 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
508	/* 0x10 */ 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
509	/* 0x18 */ 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
510	/* 0x20 */ 0x20, 0x21, 0x22, 0x23, 0xa2, 0x25, 0x26, 0x27,
511	/* 0x28 */ 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
512	/* 0x30 */ 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
513	/* 0x38 */ 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
514	/* 0x40 */ 0xa0, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
515	/* 0x48 */ 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
516	/* 0x50 */ 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
517	/* 0x58 */ 0x58, 0x59, 0x5a, 0xfa, 0xfb, 0xfc, 0x1d, 0xc4,
518	/* 0x60 */ 0x96, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
519	/* 0x68 */ 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
520	/* 0x70 */ 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
521	/* 0x78 */ 0x78, 0x79, 0x7a, 0xfd, 0xfe, 0xff, 0xce, 0x20,
522	/* 0x80 */ 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
523	/* 0x88 */ 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
524	/* 0x90 */ 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
525	/* 0x98 */ 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
526	/* 0xA0 */ 0x20, 0x40, 0xb1, 0xa1, 0x24, 0xa3, 0xfe, 0x5f,
527	/* 0xA8 */ 0x22, 0xc8, 0x61, 0x14, 0x97, 0x2d, 0xad, 0x96,
528	/* 0xB0 */ 0x80, 0x8c, 0x82, 0x83, 0x27, 0x8f, 0x86, 0xdd,
529	/* 0xB8 */ 0x2c, 0x81, 0x6f, 0x15, 0x8b, 0x8a, 0x84, 0x60,
530	/* 0xC0 */ 0xe2, 0xe2, 0xe2, 0x5b, 0x5b, 0xae, 0xbc, 0xa9,
531	/* 0xC8 */ 0xc5, 0xbf, 0xc6, 0xf1, 0xe3, 0xe3, 0xe3, 0xe3,
532	/* 0xD0 */ 0x44, 0x5d, 0xa8, 0xe4, 0xec, 0xec, 0x5c, 0x78,
533	/* 0xD8 */ 0xab, 0xa6, 0xe5, 0x5e, 0x5e, 0xe6, 0xaa, 0xbe,
534	/* 0xE0 */ 0x7f, 0xe7, 0xaf, 0x7b, 0x7b, 0xaf, 0xbd, 0xc8,
535	/* 0xE8 */ 0xa4, 0xa5, 0xc7, 0xf6, 0xa7, 0xe8, 0x69, 0x69,
536	/* 0xF0 */ 0xed, 0x7d, 0xa8, 0xe4, 0xec, 0x5c, 0x5c, 0x25,
537	/* 0xF8 */ 0xac, 0xa6, 0xea, 0xef, 0x7e, 0xeb, 0xb2, 0x79,
538};
539
540static const char old_keypad_profile[][4][9] = {
541	{"S0", "Left\n", "Left\n", ""},
542	{"S1", "Down\n", "Down\n", ""},
543	{"S2", "Up\n", "Up\n", ""},
544	{"S3", "Right\n", "Right\n", ""},
545	{"S4", "Esc\n", "Esc\n", ""},
546	{"S5", "Ret\n", "Ret\n", ""},
547	{"", "", "", ""}
548};
549
550/* signals, press, repeat, release */
551static const char new_keypad_profile[][4][9] = {
552	{"S0", "Left\n", "Left\n", ""},
553	{"S1", "Down\n", "Down\n", ""},
554	{"S2", "Up\n", "Up\n", ""},
555	{"S3", "Right\n", "Right\n", ""},
556	{"S4s5", "", "Esc\n", "Esc\n"},
557	{"s4S5", "", "Ret\n", "Ret\n"},
558	{"S4S5", "Help\n", "", ""},
559	/* add new signals above this line */
560	{"", "", "", ""}
561};
562
563/* signals, press, repeat, release */
564static const char nexcom_keypad_profile[][4][9] = {
565	{"a-p-e-", "Down\n", "Down\n", ""},
566	{"a-p-E-", "Ret\n", "Ret\n", ""},
567	{"a-P-E-", "Esc\n", "Esc\n", ""},
568	{"a-P-e-", "Up\n", "Up\n", ""},
569	/* add new signals above this line */
570	{"", "", "", ""}
571};
572
573static const char (*keypad_profile)[4][9] = old_keypad_profile;
574
575static DECLARE_BITMAP(bits, LCD_BITS);
576
577static void lcd_get_bits(unsigned int port, int *val)
578{
579	unsigned int bit, state;
580
581	for (bit = 0; bit < LCD_BITS; bit++) {
582		state = test_bit(bit, bits) ? BIT_SET : BIT_CLR;
583		*val &= lcd_bits[port][bit][BIT_MSK];
584		*val |= lcd_bits[port][bit][state];
585	}
586}
587
588/* sets data port bits according to current signals values */
589static int set_data_bits(void)
590{
591	int val;
592
593	val = r_dtr(pprt);
594	lcd_get_bits(LCD_PORT_D, &val);
595	w_dtr(pprt, val);
596	return val;
597}
598
599/* sets ctrl port bits according to current signals values */
600static int set_ctrl_bits(void)
601{
602	int val;
603
604	val = r_ctr(pprt);
605	lcd_get_bits(LCD_PORT_C, &val);
606	w_ctr(pprt, val);
607	return val;
608}
609
610/* sets ctrl & data port bits according to current signals values */
611static void panel_set_bits(void)
612{
613	set_data_bits();
614	set_ctrl_bits();
615}
616
617/*
618 * Converts a parallel port pin (from -25 to 25) to data and control ports
619 * masks, and data and control port bits. The signal will be considered
620 * unconnected if it's on pin 0 or an invalid pin (<-25 or >25).
621 *
622 * Result will be used this way :
623 *   out(dport, in(dport) & d_val[2] | d_val[signal_state])
624 *   out(cport, in(cport) & c_val[2] | c_val[signal_state])
625 */
626static void pin_to_bits(int pin, unsigned char *d_val, unsigned char *c_val)
627{
628	int d_bit, c_bit, inv;
629
630	d_val[0] = 0;
631	c_val[0] = 0;
632	d_val[1] = 0;
633	c_val[1] = 0;
634	d_val[2] = 0xFF;
635	c_val[2] = 0xFF;
636
637	if (pin == 0)
638		return;
639
640	inv = (pin < 0);
641	if (inv)
642		pin = -pin;
643
644	d_bit = 0;
645	c_bit = 0;
646
647	switch (pin) {
648	case PIN_STROBE:	/* strobe, inverted */
649		c_bit = PNL_PSTROBE;
650		inv = !inv;
651		break;
652	case PIN_D0...PIN_D7:	/* D0 - D7 = 2 - 9 */
653		d_bit = 1 << (pin - 2);
654		break;
655	case PIN_AUTOLF:	/* autofeed, inverted */
656		c_bit = PNL_PAUTOLF;
657		inv = !inv;
658		break;
659	case PIN_INITP:		/* init, direct */
660		c_bit = PNL_PINITP;
661		break;
662	case PIN_SELECP:	/* select_in, inverted */
663		c_bit = PNL_PSELECP;
664		inv = !inv;
665		break;
666	default:		/* unknown pin, ignore */
667		break;
668	}
669
670	if (c_bit) {
671		c_val[2] &= ~c_bit;
672		c_val[!inv] = c_bit;
673	} else if (d_bit) {
674		d_val[2] &= ~d_bit;
675		d_val[!inv] = d_bit;
676	}
677}
678
679/*
680 * send a serial byte to the LCD panel. The caller is responsible for locking
681 * if needed.
682 */
683static void lcd_send_serial(int byte)
684{
685	int bit;
686
687	/*
688	 * the data bit is set on D0, and the clock on STROBE.
689	 * LCD reads D0 on STROBE's rising edge.
690	 */
691	for (bit = 0; bit < 8; bit++) {
692		clear_bit(LCD_BIT_CL, bits);	/* CLK low */
693		panel_set_bits();
694		if (byte & 1) {
695			set_bit(LCD_BIT_DA, bits);
696		} else {
697			clear_bit(LCD_BIT_DA, bits);
698		}
699
700		panel_set_bits();
701		udelay(2);  /* maintain the data during 2 us before CLK up */
702		set_bit(LCD_BIT_CL, bits);	/* CLK high */
703		panel_set_bits();
704		udelay(1);  /* maintain the strobe during 1 us */
705		byte >>= 1;
706	}
707}
708
709/* turn the backlight on or off */
710static void lcd_backlight(struct charlcd *charlcd, enum charlcd_onoff on)
711{
712	if (lcd.pins.bl == PIN_NONE)
713		return;
714
715	/* The backlight is activated by setting the AUTOFEED line to +5V  */
716	spin_lock_irq(&pprt_lock);
717	if (on)
718		set_bit(LCD_BIT_BL, bits);
719	else
720		clear_bit(LCD_BIT_BL, bits);
721	panel_set_bits();
722	spin_unlock_irq(&pprt_lock);
723}
724
725/* send a command to the LCD panel in serial mode */
726static void lcd_write_cmd_s(struct hd44780_common *hdc, int cmd)
727{
728	spin_lock_irq(&pprt_lock);
729	lcd_send_serial(0x1F);	/* R/W=W, RS=0 */
730	lcd_send_serial(cmd & 0x0F);
731	lcd_send_serial((cmd >> 4) & 0x0F);
732	udelay(40);		/* the shortest command takes at least 40 us */
733	spin_unlock_irq(&pprt_lock);
734}
735
736/* send data to the LCD panel in serial mode */
737static void lcd_write_data_s(struct hd44780_common *hdc, int data)
738{
739	spin_lock_irq(&pprt_lock);
740	lcd_send_serial(0x5F);	/* R/W=W, RS=1 */
741	lcd_send_serial(data & 0x0F);
742	lcd_send_serial((data >> 4) & 0x0F);
743	udelay(40);		/* the shortest data takes at least 40 us */
744	spin_unlock_irq(&pprt_lock);
745}
746
747/* send a command to the LCD panel in 8 bits parallel mode */
748static void lcd_write_cmd_p8(struct hd44780_common *hdc, int cmd)
749{
750	spin_lock_irq(&pprt_lock);
751	/* present the data to the data port */
752	w_dtr(pprt, cmd);
753	udelay(20);	/* maintain the data during 20 us before the strobe */
754
755	set_bit(LCD_BIT_E, bits);
756	clear_bit(LCD_BIT_RS, bits);
757	clear_bit(LCD_BIT_RW, bits);
758	set_ctrl_bits();
759
760	udelay(40);	/* maintain the strobe during 40 us */
761
762	clear_bit(LCD_BIT_E, bits);
763	set_ctrl_bits();
764
765	udelay(120);	/* the shortest command takes at least 120 us */
766	spin_unlock_irq(&pprt_lock);
767}
768
769/* send data to the LCD panel in 8 bits parallel mode */
770static void lcd_write_data_p8(struct hd44780_common *hdc, int data)
771{
772	spin_lock_irq(&pprt_lock);
773	/* present the data to the data port */
774	w_dtr(pprt, data);
775	udelay(20);	/* maintain the data during 20 us before the strobe */
776
777	set_bit(LCD_BIT_E, bits);
778	set_bit(LCD_BIT_RS, bits);
779	clear_bit(LCD_BIT_RW, bits);
780	set_ctrl_bits();
781
782	udelay(40);	/* maintain the strobe during 40 us */
783
784	clear_bit(LCD_BIT_E, bits);
785	set_ctrl_bits();
786
787	udelay(45);	/* the shortest data takes at least 45 us */
788	spin_unlock_irq(&pprt_lock);
789}
790
791/* send a command to the TI LCD panel */
792static void lcd_write_cmd_tilcd(struct hd44780_common *hdc, int cmd)
793{
794	spin_lock_irq(&pprt_lock);
795	/* present the data to the control port */
796	w_ctr(pprt, cmd);
797	udelay(60);
798	spin_unlock_irq(&pprt_lock);
799}
800
801/* send data to the TI LCD panel */
802static void lcd_write_data_tilcd(struct hd44780_common *hdc, int data)
803{
804	spin_lock_irq(&pprt_lock);
805	/* present the data to the data port */
806	w_dtr(pprt, data);
807	udelay(60);
808	spin_unlock_irq(&pprt_lock);
809}
810
811static const struct charlcd_ops charlcd_ops = {
812	.backlight	= lcd_backlight,
813	.print		= hd44780_common_print,
814	.gotoxy		= hd44780_common_gotoxy,
815	.home		= hd44780_common_home,
816	.clear_display	= hd44780_common_clear_display,
817	.init_display	= hd44780_common_init_display,
818	.shift_cursor	= hd44780_common_shift_cursor,
819	.shift_display	= hd44780_common_shift_display,
820	.display	= hd44780_common_display,
821	.cursor		= hd44780_common_cursor,
822	.blink		= hd44780_common_blink,
823	.fontsize	= hd44780_common_fontsize,
824	.lines		= hd44780_common_lines,
825	.redefine_char	= hd44780_common_redefine_char,
826};
827
828/* initialize the LCD driver */
829static void lcd_init(void)
830{
831	struct charlcd *charlcd;
832	struct hd44780_common *hdc;
833
834	hdc = hd44780_common_alloc();
835	if (!hdc)
836		return;
837
838	charlcd = charlcd_alloc();
839	if (!charlcd) {
840		kfree(hdc);
841		return;
842	}
843
844	hdc->hd44780 = &lcd;
845	charlcd->drvdata = hdc;
846
847	/*
848	 * Init lcd struct with load-time values to preserve exact
849	 * current functionality (at least for now).
850	 */
851	charlcd->height = lcd_height;
852	charlcd->width = lcd_width;
853	hdc->bwidth = lcd_bwidth;
854	hdc->hwidth = lcd_hwidth;
855
856	switch (selected_lcd_type) {
857	case LCD_TYPE_OLD:
858		/* parallel mode, 8 bits */
859		lcd.proto = LCD_PROTO_PARALLEL;
860		lcd.charset = LCD_CHARSET_NORMAL;
861		lcd.pins.e = PIN_STROBE;
862		lcd.pins.rs = PIN_AUTOLF;
863
864		charlcd->width = 40;
865		hdc->bwidth = 40;
866		hdc->hwidth = 64;
867		charlcd->height = 2;
868		break;
869	case LCD_TYPE_KS0074:
870		/* serial mode, ks0074 */
871		lcd.proto = LCD_PROTO_SERIAL;
872		lcd.charset = LCD_CHARSET_KS0074;
873		lcd.pins.bl = PIN_AUTOLF;
874		lcd.pins.cl = PIN_STROBE;
875		lcd.pins.da = PIN_D0;
876
877		charlcd->width = 16;
878		hdc->bwidth = 40;
879		hdc->hwidth = 16;
880		charlcd->height = 2;
881		break;
882	case LCD_TYPE_NEXCOM:
883		/* parallel mode, 8 bits, generic */
884		lcd.proto = LCD_PROTO_PARALLEL;
885		lcd.charset = LCD_CHARSET_NORMAL;
886		lcd.pins.e = PIN_AUTOLF;
887		lcd.pins.rs = PIN_SELECP;
888		lcd.pins.rw = PIN_INITP;
889
890		charlcd->width = 16;
891		hdc->bwidth = 40;
892		hdc->hwidth = 64;
893		charlcd->height = 2;
894		break;
895	case LCD_TYPE_CUSTOM:
896		/* customer-defined */
897		lcd.proto = DEFAULT_LCD_PROTO;
898		lcd.charset = DEFAULT_LCD_CHARSET;
899		/* default geometry will be set later */
900		break;
901	case LCD_TYPE_HANTRONIX:
902		/* parallel mode, 8 bits, hantronix-like */
903	default:
904		lcd.proto = LCD_PROTO_PARALLEL;
905		lcd.charset = LCD_CHARSET_NORMAL;
906		lcd.pins.e = PIN_STROBE;
907		lcd.pins.rs = PIN_SELECP;
908
909		charlcd->width = 16;
910		hdc->bwidth = 40;
911		hdc->hwidth = 64;
912		charlcd->height = 2;
913		break;
914	}
915
916	/* Overwrite with module params set on loading */
917	if (lcd_height != NOT_SET)
918		charlcd->height = lcd_height;
919	if (lcd_width != NOT_SET)
920		charlcd->width = lcd_width;
921	if (lcd_bwidth != NOT_SET)
922		hdc->bwidth = lcd_bwidth;
923	if (lcd_hwidth != NOT_SET)
924		hdc->hwidth = lcd_hwidth;
925	if (lcd_charset != NOT_SET)
926		lcd.charset = lcd_charset;
927	if (lcd_proto != NOT_SET)
928		lcd.proto = lcd_proto;
929	if (lcd_e_pin != PIN_NOT_SET)
930		lcd.pins.e = lcd_e_pin;
931	if (lcd_rs_pin != PIN_NOT_SET)
932		lcd.pins.rs = lcd_rs_pin;
933	if (lcd_rw_pin != PIN_NOT_SET)
934		lcd.pins.rw = lcd_rw_pin;
935	if (lcd_cl_pin != PIN_NOT_SET)
936		lcd.pins.cl = lcd_cl_pin;
937	if (lcd_da_pin != PIN_NOT_SET)
938		lcd.pins.da = lcd_da_pin;
939	if (lcd_bl_pin != PIN_NOT_SET)
940		lcd.pins.bl = lcd_bl_pin;
941
942	/* this is used to catch wrong and default values */
943	if (charlcd->width <= 0)
944		charlcd->width = DEFAULT_LCD_WIDTH;
945	if (hdc->bwidth <= 0)
946		hdc->bwidth = DEFAULT_LCD_BWIDTH;
947	if (hdc->hwidth <= 0)
948		hdc->hwidth = DEFAULT_LCD_HWIDTH;
949	if (charlcd->height <= 0)
950		charlcd->height = DEFAULT_LCD_HEIGHT;
951
952	if (lcd.proto == LCD_PROTO_SERIAL) {	/* SERIAL */
953		charlcd->ops = &charlcd_ops;
954		hdc->write_data = lcd_write_data_s;
955		hdc->write_cmd = lcd_write_cmd_s;
956
957		if (lcd.pins.cl == PIN_NOT_SET)
958			lcd.pins.cl = DEFAULT_LCD_PIN_SCL;
959		if (lcd.pins.da == PIN_NOT_SET)
960			lcd.pins.da = DEFAULT_LCD_PIN_SDA;
961
962	} else if (lcd.proto == LCD_PROTO_PARALLEL) {	/* PARALLEL */
963		charlcd->ops = &charlcd_ops;
964		hdc->write_data = lcd_write_data_p8;
965		hdc->write_cmd = lcd_write_cmd_p8;
966
967		if (lcd.pins.e == PIN_NOT_SET)
968			lcd.pins.e = DEFAULT_LCD_PIN_E;
969		if (lcd.pins.rs == PIN_NOT_SET)
970			lcd.pins.rs = DEFAULT_LCD_PIN_RS;
971		if (lcd.pins.rw == PIN_NOT_SET)
972			lcd.pins.rw = DEFAULT_LCD_PIN_RW;
973	} else {
974		charlcd->ops = &charlcd_ops;
975		hdc->write_data = lcd_write_data_tilcd;
976		hdc->write_cmd = lcd_write_cmd_tilcd;
977	}
978
979	if (lcd.pins.bl == PIN_NOT_SET)
980		lcd.pins.bl = DEFAULT_LCD_PIN_BL;
981
982	if (lcd.pins.e == PIN_NOT_SET)
983		lcd.pins.e = PIN_NONE;
984	if (lcd.pins.rs == PIN_NOT_SET)
985		lcd.pins.rs = PIN_NONE;
986	if (lcd.pins.rw == PIN_NOT_SET)
987		lcd.pins.rw = PIN_NONE;
988	if (lcd.pins.bl == PIN_NOT_SET)
989		lcd.pins.bl = PIN_NONE;
990	if (lcd.pins.cl == PIN_NOT_SET)
991		lcd.pins.cl = PIN_NONE;
992	if (lcd.pins.da == PIN_NOT_SET)
993		lcd.pins.da = PIN_NONE;
994
995	if (lcd.charset == NOT_SET)
996		lcd.charset = DEFAULT_LCD_CHARSET;
997
998	if (lcd.charset == LCD_CHARSET_KS0074)
999		charlcd->char_conv = lcd_char_conv_ks0074;
1000	else
1001		charlcd->char_conv = NULL;
1002
1003	pin_to_bits(lcd.pins.e, lcd_bits[LCD_PORT_D][LCD_BIT_E],
1004		    lcd_bits[LCD_PORT_C][LCD_BIT_E]);
1005	pin_to_bits(lcd.pins.rs, lcd_bits[LCD_PORT_D][LCD_BIT_RS],
1006		    lcd_bits[LCD_PORT_C][LCD_BIT_RS]);
1007	pin_to_bits(lcd.pins.rw, lcd_bits[LCD_PORT_D][LCD_BIT_RW],
1008		    lcd_bits[LCD_PORT_C][LCD_BIT_RW]);
1009	pin_to_bits(lcd.pins.bl, lcd_bits[LCD_PORT_D][LCD_BIT_BL],
1010		    lcd_bits[LCD_PORT_C][LCD_BIT_BL]);
1011	pin_to_bits(lcd.pins.cl, lcd_bits[LCD_PORT_D][LCD_BIT_CL],
1012		    lcd_bits[LCD_PORT_C][LCD_BIT_CL]);
1013	pin_to_bits(lcd.pins.da, lcd_bits[LCD_PORT_D][LCD_BIT_DA],
1014		    lcd_bits[LCD_PORT_C][LCD_BIT_DA]);
1015
1016	lcd.charlcd = charlcd;
1017	lcd.initialized = true;
1018}
1019
1020/*
1021 * These are the file operation function for user access to /dev/keypad
1022 */
1023
1024static ssize_t keypad_read(struct file *file,
1025			   char __user *buf, size_t count, loff_t *ppos)
1026{
1027	unsigned i = *ppos;
1028	char __user *tmp = buf;
1029
1030	if (keypad_buflen == 0) {
1031		if (file->f_flags & O_NONBLOCK)
1032			return -EAGAIN;
1033
1034		if (wait_event_interruptible(keypad_read_wait,
1035					     keypad_buflen != 0))
1036			return -EINTR;
1037	}
1038
1039	for (; count-- > 0 && (keypad_buflen > 0);
1040	     ++i, ++tmp, --keypad_buflen) {
1041		put_user(keypad_buffer[keypad_start], tmp);
1042		keypad_start = (keypad_start + 1) % KEYPAD_BUFFER;
1043	}
1044	*ppos = i;
1045
1046	return tmp - buf;
1047}
1048
1049static int keypad_open(struct inode *inode, struct file *file)
1050{
1051	int ret;
1052
1053	ret = -EBUSY;
1054	if (!atomic_dec_and_test(&keypad_available))
1055		goto fail;	/* open only once at a time */
1056
1057	ret = -EPERM;
1058	if (file->f_mode & FMODE_WRITE)	/* device is read-only */
1059		goto fail;
1060
1061	keypad_buflen = 0;	/* flush the buffer on opening */
1062	return 0;
1063 fail:
1064	atomic_inc(&keypad_available);
1065	return ret;
1066}
1067
1068static int keypad_release(struct inode *inode, struct file *file)
1069{
1070	atomic_inc(&keypad_available);
1071	return 0;
1072}
1073
1074static const struct file_operations keypad_fops = {
1075	.read    = keypad_read,		/* read */
1076	.open    = keypad_open,		/* open */
1077	.release = keypad_release,	/* close */
1078	.llseek  = default_llseek,
1079};
1080
1081static struct miscdevice keypad_dev = {
1082	.minor	= KEYPAD_MINOR,
1083	.name	= "keypad",
1084	.fops	= &keypad_fops,
1085};
1086
1087static void keypad_send_key(const char *string, int max_len)
1088{
1089	/* send the key to the device only if a process is attached to it. */
1090	if (!atomic_read(&keypad_available)) {
1091		while (max_len-- && keypad_buflen < KEYPAD_BUFFER && *string) {
1092			keypad_buffer[(keypad_start + keypad_buflen++) %
1093				      KEYPAD_BUFFER] = *string++;
1094		}
1095		wake_up_interruptible(&keypad_read_wait);
1096	}
1097}
1098
1099/* this function scans all the bits involving at least one logical signal,
1100 * and puts the results in the bitfield "phys_read" (one bit per established
1101 * contact), and sets "phys_read_prev" to "phys_read".
1102 *
1103 * Note: to debounce input signals, we will only consider as switched a signal
1104 * which is stable across 2 measures. Signals which are different between two
1105 * reads will be kept as they previously were in their logical form (phys_prev).
1106 * A signal which has just switched will have a 1 in
1107 * (phys_read ^ phys_read_prev).
1108 */
1109static void phys_scan_contacts(void)
1110{
1111	int bit, bitval;
1112	char oldval;
1113	char bitmask;
1114	char gndmask;
1115
1116	phys_prev = phys_curr;
1117	phys_read_prev = phys_read;
1118	phys_read = 0;		/* flush all signals */
1119
1120	/* keep track of old value, with all outputs disabled */
1121	oldval = r_dtr(pprt) | scan_mask_o;
1122	/* activate all keyboard outputs (active low) */
1123	w_dtr(pprt, oldval & ~scan_mask_o);
1124
1125	/* will have a 1 for each bit set to gnd */
1126	bitmask = PNL_PINPUT(r_str(pprt)) & scan_mask_i;
1127	/* disable all matrix signals */
1128	w_dtr(pprt, oldval);
1129
1130	/* now that all outputs are cleared, the only active input bits are
1131	 * directly connected to the ground
1132	 */
1133
1134	/* 1 for each grounded input */
1135	gndmask = PNL_PINPUT(r_str(pprt)) & scan_mask_i;
1136
1137	/* grounded inputs are signals 40-44 */
1138	phys_read |= (__u64)gndmask << 40;
1139
1140	if (bitmask != gndmask) {
1141		/*
1142		 * since clearing the outputs changed some inputs, we know
1143		 * that some input signals are currently tied to some outputs.
1144		 * So we'll scan them.
1145		 */
1146		for (bit = 0; bit < 8; bit++) {
1147			bitval = BIT(bit);
1148
1149			if (!(scan_mask_o & bitval))	/* skip unused bits */
1150				continue;
1151
1152			w_dtr(pprt, oldval & ~bitval);	/* enable this output */
1153			bitmask = PNL_PINPUT(r_str(pprt)) & ~gndmask;
1154			phys_read |= (__u64)bitmask << (5 * bit);
1155		}
1156		w_dtr(pprt, oldval);	/* disable all outputs */
1157	}
1158	/*
1159	 * this is easy: use old bits when they are flapping,
1160	 * use new ones when stable
1161	 */
1162	phys_curr = (phys_prev & (phys_read ^ phys_read_prev)) |
1163		    (phys_read & ~(phys_read ^ phys_read_prev));
1164}
1165
1166static inline int input_state_high(struct logical_input *input)
1167{
1168#if 0
1169	/* FIXME:
1170	 * this is an invalid test. It tries to catch
1171	 * transitions from single-key to multiple-key, but
1172	 * doesn't take into account the contacts polarity.
1173	 * The only solution to the problem is to parse keys
1174	 * from the most complex to the simplest combinations,
1175	 * and mark them as 'caught' once a combination
1176	 * matches, then unmatch it for all other ones.
1177	 */
1178
1179	/* try to catch dangerous transitions cases :
1180	 * someone adds a bit, so this signal was a false
1181	 * positive resulting from a transition. We should
1182	 * invalidate the signal immediately and not call the
1183	 * release function.
1184	 * eg: 0 -(press A)-> A -(press B)-> AB : don't match A's release.
1185	 */
1186	if (((phys_prev & input->mask) == input->value) &&
1187	    ((phys_curr & input->mask) >  input->value)) {
1188		input->state = INPUT_ST_LOW; /* invalidate */
1189		return 1;
1190	}
1191#endif
1192
1193	if ((phys_curr & input->mask) == input->value) {
1194		if ((input->type == INPUT_TYPE_STD) &&
1195		    (input->high_timer == 0)) {
1196			input->high_timer++;
1197			if (input->u.std.press_fct)
1198				input->u.std.press_fct(input->u.std.press_data);
1199		} else if (input->type == INPUT_TYPE_KBD) {
1200			/* will turn on the light */
1201			keypressed = 1;
1202
1203			if (input->high_timer == 0) {
1204				char *press_str = input->u.kbd.press_str;
1205
1206				if (press_str[0]) {
1207					int s = sizeof(input->u.kbd.press_str);
1208
1209					keypad_send_key(press_str, s);
1210				}
1211			}
1212
1213			if (input->u.kbd.repeat_str[0]) {
1214				char *repeat_str = input->u.kbd.repeat_str;
1215
1216				if (input->high_timer >= KEYPAD_REP_START) {
1217					int s = sizeof(input->u.kbd.repeat_str);
1218
1219					input->high_timer -= KEYPAD_REP_DELAY;
1220					keypad_send_key(repeat_str, s);
1221				}
1222				/* we will need to come back here soon */
1223				inputs_stable = 0;
1224			}
1225
1226			if (input->high_timer < 255)
1227				input->high_timer++;
1228		}
1229		return 1;
1230	}
1231
1232	/* else signal falling down. Let's fall through. */
1233	input->state = INPUT_ST_FALLING;
1234	input->fall_timer = 0;
1235
1236	return 0;
1237}
1238
1239static inline void input_state_falling(struct logical_input *input)
1240{
1241#if 0
1242	/* FIXME !!! same comment as in input_state_high */
1243	if (((phys_prev & input->mask) == input->value) &&
1244	    ((phys_curr & input->mask) >  input->value)) {
1245		input->state = INPUT_ST_LOW;	/* invalidate */
1246		return;
1247	}
1248#endif
1249
1250	if ((phys_curr & input->mask) == input->value) {
1251		if (input->type == INPUT_TYPE_KBD) {
1252			/* will turn on the light */
1253			keypressed = 1;
1254
1255			if (input->u.kbd.repeat_str[0]) {
1256				char *repeat_str = input->u.kbd.repeat_str;
1257
1258				if (input->high_timer >= KEYPAD_REP_START) {
1259					int s = sizeof(input->u.kbd.repeat_str);
1260
1261					input->high_timer -= KEYPAD_REP_DELAY;
1262					keypad_send_key(repeat_str, s);
1263				}
1264				/* we will need to come back here soon */
1265				inputs_stable = 0;
1266			}
1267
1268			if (input->high_timer < 255)
1269				input->high_timer++;
1270		}
1271		input->state = INPUT_ST_HIGH;
1272	} else if (input->fall_timer >= input->fall_time) {
1273		/* call release event */
1274		if (input->type == INPUT_TYPE_STD) {
1275			void (*release_fct)(int) = input->u.std.release_fct;
1276
1277			if (release_fct)
1278				release_fct(input->u.std.release_data);
1279		} else if (input->type == INPUT_TYPE_KBD) {
1280			char *release_str = input->u.kbd.release_str;
1281
1282			if (release_str[0]) {
1283				int s = sizeof(input->u.kbd.release_str);
1284
1285				keypad_send_key(release_str, s);
1286			}
1287		}
1288
1289		input->state = INPUT_ST_LOW;
1290	} else {
1291		input->fall_timer++;
1292		inputs_stable = 0;
1293	}
1294}
1295
1296static void panel_process_inputs(void)
1297{
1298	struct logical_input *input;
1299
1300	keypressed = 0;
1301	inputs_stable = 1;
1302	list_for_each_entry(input, &logical_inputs, list) {
1303		switch (input->state) {
1304		case INPUT_ST_LOW:
1305			if ((phys_curr & input->mask) != input->value)
1306				break;
1307			/* if all needed ones were already set previously,
1308			 * this means that this logical signal has been
1309			 * activated by the releasing of another combined
1310			 * signal, so we don't want to match.
1311			 * eg: AB -(release B)-> A -(release A)-> 0 :
1312			 *     don't match A.
1313			 */
1314			if ((phys_prev & input->mask) == input->value)
1315				break;
1316			input->rise_timer = 0;
1317			input->state = INPUT_ST_RISING;
1318			fallthrough;
1319		case INPUT_ST_RISING:
1320			if ((phys_curr & input->mask) != input->value) {
1321				input->state = INPUT_ST_LOW;
1322				break;
1323			}
1324			if (input->rise_timer < input->rise_time) {
1325				inputs_stable = 0;
1326				input->rise_timer++;
1327				break;
1328			}
1329			input->high_timer = 0;
1330			input->state = INPUT_ST_HIGH;
1331			fallthrough;
1332		case INPUT_ST_HIGH:
1333			if (input_state_high(input))
1334				break;
1335			fallthrough;
1336		case INPUT_ST_FALLING:
1337			input_state_falling(input);
1338		}
1339	}
1340}
1341
1342static void panel_scan_timer(struct timer_list *unused)
1343{
1344	if (keypad.enabled && keypad_initialized) {
1345		if (spin_trylock_irq(&pprt_lock)) {
1346			phys_scan_contacts();
1347
1348			/* no need for the parport anymore */
1349			spin_unlock_irq(&pprt_lock);
1350		}
1351
1352		if (!inputs_stable || phys_curr != phys_prev)
1353			panel_process_inputs();
1354	}
1355
1356	if (keypressed && lcd.enabled && lcd.initialized)
1357		charlcd_poke(lcd.charlcd);
1358
1359	mod_timer(&scan_timer, jiffies + INPUT_POLL_TIME);
1360}
1361
1362static void init_scan_timer(void)
1363{
1364	if (scan_timer.function)
1365		return;		/* already started */
1366
1367	timer_setup(&scan_timer, panel_scan_timer, 0);
1368	scan_timer.expires = jiffies + INPUT_POLL_TIME;
1369	add_timer(&scan_timer);
1370}
1371
1372/* converts a name of the form "({BbAaPpSsEe}{01234567-})*" to a series of bits.
1373 * if <omask> or <imask> are non-null, they will be or'ed with the bits
1374 * corresponding to out and in bits respectively.
1375 * returns 1 if ok, 0 if error (in which case, nothing is written).
1376 */
1377static u8 input_name2mask(const char *name, __u64 *mask, __u64 *value,
1378			  u8 *imask, u8 *omask)
1379{
1380	const char sigtab[] = "EeSsPpAaBb";
1381	u8 im, om;
1382	__u64 m, v;
1383
1384	om = 0;
1385	im = 0;
1386	m = 0ULL;
1387	v = 0ULL;
1388	while (*name) {
1389		int in, out, bit, neg;
1390		const char *idx;
1391
1392		idx = strchr(sigtab, *name);
1393		if (!idx)
1394			return 0;	/* input name not found */
1395
1396		in = idx - sigtab;
1397		neg = (in & 1);	/* odd (lower) names are negated */
1398		in >>= 1;
1399		im |= BIT(in);
1400
1401		name++;
1402		if (*name >= '0' && *name <= '7') {
1403			out = *name - '0';
1404			om |= BIT(out);
1405		} else if (*name == '-') {
1406			out = 8;
1407		} else {
1408			return 0;	/* unknown bit name */
1409		}
1410
1411		bit = (out * 5) + in;
1412
1413		m |= 1ULL << bit;
1414		if (!neg)
1415			v |= 1ULL << bit;
1416		name++;
1417	}
1418	*mask = m;
1419	*value = v;
1420	if (imask)
1421		*imask |= im;
1422	if (omask)
1423		*omask |= om;
1424	return 1;
1425}
1426
1427/* tries to bind a key to the signal name <name>. The key will send the
1428 * strings <press>, <repeat>, <release> for these respective events.
1429 * Returns the pointer to the new key if ok, NULL if the key could not be bound.
1430 */
1431static struct logical_input *panel_bind_key(const char *name, const char *press,
1432					    const char *repeat,
1433					    const char *release)
1434{
1435	struct logical_input *key;
1436
1437	key = kzalloc(sizeof(*key), GFP_KERNEL);
1438	if (!key)
1439		return NULL;
1440
1441	if (!input_name2mask(name, &key->mask, &key->value, &scan_mask_i,
1442			     &scan_mask_o)) {
1443		kfree(key);
1444		return NULL;
1445	}
1446
1447	key->type = INPUT_TYPE_KBD;
1448	key->state = INPUT_ST_LOW;
1449	key->rise_time = 1;
1450	key->fall_time = 1;
1451
1452	strtomem_pad(key->u.kbd.press_str, press, '\0');
1453	strtomem_pad(key->u.kbd.repeat_str, repeat, '\0');
1454	strtomem_pad(key->u.kbd.release_str, release, '\0');
1455	list_add(&key->list, &logical_inputs);
1456	return key;
1457}
1458
1459#if 0
1460/* tries to bind a callback function to the signal name <name>. The function
1461 * <press_fct> will be called with the <press_data> arg when the signal is
1462 * activated, and so on for <release_fct>/<release_data>
1463 * Returns the pointer to the new signal if ok, NULL if the signal could not
1464 * be bound.
1465 */
1466static struct logical_input *panel_bind_callback(char *name,
1467						 void (*press_fct)(int),
1468						 int press_data,
1469						 void (*release_fct)(int),
1470						 int release_data)
1471{
1472	struct logical_input *callback;
1473
1474	callback = kmalloc(sizeof(*callback), GFP_KERNEL);
1475	if (!callback)
1476		return NULL;
1477
1478	memset(callback, 0, sizeof(struct logical_input));
1479	if (!input_name2mask(name, &callback->mask, &callback->value,
1480			     &scan_mask_i, &scan_mask_o))
1481		return NULL;
1482
1483	callback->type = INPUT_TYPE_STD;
1484	callback->state = INPUT_ST_LOW;
1485	callback->rise_time = 1;
1486	callback->fall_time = 1;
1487	callback->u.std.press_fct = press_fct;
1488	callback->u.std.press_data = press_data;
1489	callback->u.std.release_fct = release_fct;
1490	callback->u.std.release_data = release_data;
1491	list_add(&callback->list, &logical_inputs);
1492	return callback;
1493}
1494#endif
1495
1496static void keypad_init(void)
1497{
1498	int keynum;
1499
1500	init_waitqueue_head(&keypad_read_wait);
1501	keypad_buflen = 0;	/* flushes any eventual noisy keystroke */
1502
1503	/* Let's create all known keys */
1504
1505	for (keynum = 0; keypad_profile[keynum][0][0]; keynum++) {
1506		panel_bind_key(keypad_profile[keynum][0],
1507			       keypad_profile[keynum][1],
1508			       keypad_profile[keynum][2],
1509			       keypad_profile[keynum][3]);
1510	}
1511
1512	init_scan_timer();
1513	keypad_initialized = 1;
1514}
1515
1516/**************************************************/
1517/* device initialization                          */
1518/**************************************************/
1519
1520static void panel_attach(struct parport *port)
1521{
1522	int selected_keypad_type = NOT_SET;
1523	struct pardev_cb panel_cb;
1524
1525	/* take care of an eventual profile */
1526	switch (profile) {
1527	case PANEL_PROFILE_CUSTOM:
1528		/* custom profile */
1529		selected_keypad_type = DEFAULT_KEYPAD_TYPE;
1530		selected_lcd_type = DEFAULT_LCD_TYPE;
1531		break;
1532	case PANEL_PROFILE_OLD:
1533		/* 8 bits, 2*16, old keypad */
1534		selected_keypad_type = KEYPAD_TYPE_OLD;
1535		selected_lcd_type = LCD_TYPE_OLD;
1536
1537		/* TODO: This two are a little hacky, sort it out later */
1538		if (lcd_width == NOT_SET)
1539			lcd_width = 16;
1540		if (lcd_hwidth == NOT_SET)
1541			lcd_hwidth = 16;
1542		break;
1543	case PANEL_PROFILE_NEW:
1544		/* serial, 2*16, new keypad */
1545		selected_keypad_type = KEYPAD_TYPE_NEW;
1546		selected_lcd_type = LCD_TYPE_KS0074;
1547		break;
1548	case PANEL_PROFILE_HANTRONIX:
1549		/* 8 bits, 2*16 hantronix-like, no keypad */
1550		selected_keypad_type = KEYPAD_TYPE_NONE;
1551		selected_lcd_type = LCD_TYPE_HANTRONIX;
1552		break;
1553	case PANEL_PROFILE_NEXCOM:
1554		/* generic 8 bits, 2*16, nexcom keypad, eg. Nexcom. */
1555		selected_keypad_type = KEYPAD_TYPE_NEXCOM;
1556		selected_lcd_type = LCD_TYPE_NEXCOM;
1557		break;
1558	case PANEL_PROFILE_LARGE:
1559		/* 8 bits, 2*40, old keypad */
1560		selected_keypad_type = KEYPAD_TYPE_OLD;
1561		selected_lcd_type = LCD_TYPE_OLD;
1562		break;
1563	}
1564
1565	/*
1566	 * Overwrite selection with module param values (both keypad and lcd),
1567	 * where the deprecated params have lower prio.
1568	 */
1569	if (keypad_enabled != NOT_SET)
1570		selected_keypad_type = keypad_enabled;
1571	if (keypad_type != NOT_SET)
1572		selected_keypad_type = keypad_type;
1573
1574	keypad.enabled = (selected_keypad_type > 0);
1575
1576	if (lcd_enabled != NOT_SET)
1577		selected_lcd_type = lcd_enabled;
1578	if (lcd_type != NOT_SET)
1579		selected_lcd_type = lcd_type;
1580
1581	lcd.enabled = (selected_lcd_type > 0);
1582
1583	if (lcd.enabled) {
1584		/*
1585		 * Init lcd struct with load-time values to preserve exact
1586		 * current functionality (at least for now).
1587		 */
1588		lcd.charset = lcd_charset;
1589		lcd.proto = lcd_proto;
1590		lcd.pins.e = lcd_e_pin;
1591		lcd.pins.rs = lcd_rs_pin;
1592		lcd.pins.rw = lcd_rw_pin;
1593		lcd.pins.cl = lcd_cl_pin;
1594		lcd.pins.da = lcd_da_pin;
1595		lcd.pins.bl = lcd_bl_pin;
1596	}
1597
1598	switch (selected_keypad_type) {
1599	case KEYPAD_TYPE_OLD:
1600		keypad_profile = old_keypad_profile;
1601		break;
1602	case KEYPAD_TYPE_NEW:
1603		keypad_profile = new_keypad_profile;
1604		break;
1605	case KEYPAD_TYPE_NEXCOM:
1606		keypad_profile = nexcom_keypad_profile;
1607		break;
1608	default:
1609		keypad_profile = NULL;
1610		break;
1611	}
1612
1613	if (!lcd.enabled && !keypad.enabled) {
1614		/* no device enabled, let's exit */
1615		pr_err("panel driver disabled.\n");
1616		return;
1617	}
1618
1619	if (port->number != parport)
1620		return;
1621
1622	if (pprt) {
1623		pr_err("%s: port->number=%d parport=%d, already registered!\n",
1624		       __func__, port->number, parport);
1625		return;
1626	}
1627
1628	memset(&panel_cb, 0, sizeof(panel_cb));
1629	panel_cb.private = &pprt;
1630	/* panel_cb.flags = 0 should be PARPORT_DEV_EXCL? */
1631
1632	pprt = parport_register_dev_model(port, "panel", &panel_cb, 0);
1633	if (!pprt) {
1634		pr_err("%s: port->number=%d parport=%d, parport_register_device() failed\n",
1635		       __func__, port->number, parport);
1636		return;
1637	}
1638
1639	if (parport_claim(pprt)) {
1640		pr_err("could not claim access to parport%d. Aborting.\n",
1641		       parport);
1642		goto err_unreg_device;
1643	}
1644
1645	/* must init LCD first, just in case an IRQ from the keypad is
1646	 * generated at keypad init
1647	 */
1648	if (lcd.enabled) {
1649		lcd_init();
1650		if (!lcd.charlcd || charlcd_register(lcd.charlcd))
1651			goto err_unreg_device;
1652	}
1653
1654	if (keypad.enabled) {
1655		keypad_init();
1656		if (misc_register(&keypad_dev))
1657			goto err_lcd_unreg;
1658	}
1659	return;
1660
1661err_lcd_unreg:
1662	if (scan_timer.function)
1663		del_timer_sync(&scan_timer);
1664	if (lcd.enabled)
1665		charlcd_unregister(lcd.charlcd);
1666err_unreg_device:
1667	kfree(lcd.charlcd);
1668	lcd.charlcd = NULL;
1669	parport_unregister_device(pprt);
1670	pprt = NULL;
1671}
1672
1673static void panel_detach(struct parport *port)
1674{
1675	if (port->number != parport)
1676		return;
1677
1678	if (!pprt) {
1679		pr_err("%s: port->number=%d parport=%d, nothing to unregister.\n",
1680		       __func__, port->number, parport);
1681		return;
1682	}
1683	if (scan_timer.function)
1684		del_timer_sync(&scan_timer);
1685
1686	if (keypad.enabled) {
1687		misc_deregister(&keypad_dev);
1688		keypad_initialized = 0;
1689	}
1690
1691	if (lcd.enabled) {
1692		charlcd_unregister(lcd.charlcd);
1693		lcd.initialized = false;
1694		kfree(lcd.charlcd->drvdata);
1695		kfree(lcd.charlcd);
1696		lcd.charlcd = NULL;
1697	}
1698
1699	/* TODO: free all input signals */
1700	parport_release(pprt);
1701	parport_unregister_device(pprt);
1702	pprt = NULL;
1703}
1704
1705static struct parport_driver panel_driver = {
1706	.name = "panel",
1707	.match_port = panel_attach,
1708	.detach = panel_detach,
1709	.devmodel = true,
1710};
1711module_parport_driver(panel_driver);
1712
1713MODULE_AUTHOR("Willy Tarreau");
1714MODULE_LICENSE("GPL");
1715