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
60#define LCD_MAXBYTES		256	/* max burst write */
61
62#define KEYPAD_BUFFER		64
63
64/* poll the keyboard this every second */
65#define INPUT_POLL_TIME		(HZ / 50)
66/* a key starts to repeat after this times INPUT_POLL_TIME */
67#define KEYPAD_REP_START	(10)
68/* a key repeats this times INPUT_POLL_TIME */
69#define KEYPAD_REP_DELAY	(2)
70
71/* converts an r_str() input to an active high, bits string : 000BAOSE */
72#define PNL_PINPUT(a)		((((unsigned char)(a)) ^ 0x7F) >> 3)
73
74#define PNL_PBUSY		0x80	/* inverted input, active low */
75#define PNL_PACK		0x40	/* direct input, active low */
76#define PNL_POUTPA		0x20	/* direct input, active high */
77#define PNL_PSELECD		0x10	/* direct input, active high */
78#define PNL_PERRORP		0x08	/* direct input, active low */
79
80#define PNL_PBIDIR		0x20	/* bi-directional ports */
81/* high to read data in or-ed with data out */
82#define PNL_PINTEN		0x10
83#define PNL_PSELECP		0x08	/* inverted output, active low */
84#define PNL_PINITP		0x04	/* direct output, active low */
85#define PNL_PAUTOLF		0x02	/* inverted output, active low */
86#define PNL_PSTROBE		0x01	/* inverted output */
87
88#define PNL_PD0			0x01
89#define PNL_PD1			0x02
90#define PNL_PD2			0x04
91#define PNL_PD3			0x08
92#define PNL_PD4			0x10
93#define PNL_PD5			0x20
94#define PNL_PD6			0x40
95#define PNL_PD7			0x80
96
97#define PIN_NONE		0
98#define PIN_STROBE		1
99#define PIN_D0			2
100#define PIN_D1			3
101#define PIN_D2			4
102#define PIN_D3			5
103#define PIN_D4			6
104#define PIN_D5			7
105#define PIN_D6			8
106#define PIN_D7			9
107#define PIN_AUTOLF		14
108#define PIN_INITP		16
109#define PIN_SELECP		17
110#define PIN_NOT_SET		127
111
112#define NOT_SET			-1
113
114/* macros to simplify use of the parallel port */
115#define r_ctr(x)        (parport_read_control((x)->port))
116#define r_dtr(x)        (parport_read_data((x)->port))
117#define r_str(x)        (parport_read_status((x)->port))
118#define w_ctr(x, y)     (parport_write_control((x)->port, (y)))
119#define w_dtr(x, y)     (parport_write_data((x)->port, (y)))
120
121/* this defines which bits are to be used and which ones to be ignored */
122/* logical or of the output bits involved in the scan matrix */
123static __u8 scan_mask_o;
124/* logical or of the input bits involved in the scan matrix */
125static __u8 scan_mask_i;
126
127enum input_type {
128	INPUT_TYPE_STD,
129	INPUT_TYPE_KBD,
130};
131
132enum input_state {
133	INPUT_ST_LOW,
134	INPUT_ST_RISING,
135	INPUT_ST_HIGH,
136	INPUT_ST_FALLING,
137};
138
139struct logical_input {
140	struct list_head list;
141	__u64 mask;
142	__u64 value;
143	enum input_type type;
144	enum input_state state;
145	__u8 rise_time, fall_time;
146	__u8 rise_timer, fall_timer, high_timer;
147
148	union {
149		struct {	/* valid when type == INPUT_TYPE_STD */
150			void (*press_fct)(int);
151			void (*release_fct)(int);
152			int press_data;
153			int release_data;
154		} std;
155		struct {	/* valid when type == INPUT_TYPE_KBD */
156			char press_str[sizeof(void *) + sizeof(int)] __nonstring;
157			char repeat_str[sizeof(void *) + sizeof(int)] __nonstring;
158			char release_str[sizeof(void *) + sizeof(int)] __nonstring;
159		} kbd;
160	} u;
161};
162
163static LIST_HEAD(logical_inputs);	/* list of all defined logical inputs */
164
165/* physical contacts history
166 * Physical contacts are a 45 bits string of 9 groups of 5 bits each.
167 * The 8 lower groups correspond to output bits 0 to 7, and the 9th group
168 * corresponds to the ground.
169 * Within each group, bits are stored in the same order as read on the port :
170 * BAPSE (busy=4, ack=3, paper empty=2, select=1, error=0).
171 * So, each __u64 is represented like this :
172 * 0000000000000000000BAPSEBAPSEBAPSEBAPSEBAPSEBAPSEBAPSEBAPSEBAPSE
173 * <-----unused------><gnd><d07><d06><d05><d04><d03><d02><d01><d00>
174 */
175
176/* what has just been read from the I/O ports */
177static __u64 phys_read;
178/* previous phys_read */
179static __u64 phys_read_prev;
180/* stabilized phys_read (phys_read|phys_read_prev) */
181static __u64 phys_curr;
182/* previous phys_curr */
183static __u64 phys_prev;
184/* 0 means that at least one logical signal needs be computed */
185static char inputs_stable;
186
187/* these variables are specific to the keypad */
188static struct {
189	bool enabled;
190} keypad;
191
192static char keypad_buffer[KEYPAD_BUFFER];
193static int keypad_buflen;
194static int keypad_start;
195static char keypressed;
196static wait_queue_head_t keypad_read_wait;
197
198/* lcd-specific variables */
199static struct {
200	bool enabled;
201	bool initialized;
202
203	int charset;
204	int proto;
205
206	/* TODO: use union here? */
207	struct {
208		int e;
209		int rs;
210		int rw;
211		int cl;
212		int da;
213		int bl;
214	} pins;
215
216	struct charlcd *charlcd;
217} lcd;
218
219/* Needed only for init */
220static int selected_lcd_type = NOT_SET;
221
222/*
223 * Bit masks to convert LCD signals to parallel port outputs.
224 * _d_ are values for data port, _c_ are for control port.
225 * [0] = signal OFF, [1] = signal ON, [2] = mask
226 */
227#define BIT_CLR		0
228#define BIT_SET		1
229#define BIT_MSK		2
230#define BIT_STATES	3
231/*
232 * one entry for each bit on the LCD
233 */
234#define LCD_BIT_E	0
235#define LCD_BIT_RS	1
236#define LCD_BIT_RW	2
237#define LCD_BIT_BL	3
238#define LCD_BIT_CL	4
239#define LCD_BIT_DA	5
240#define LCD_BITS	6
241
242/*
243 * each bit can be either connected to a DATA or CTRL port
244 */
245#define LCD_PORT_C	0
246#define LCD_PORT_D	1
247#define LCD_PORTS	2
248
249static unsigned char lcd_bits[LCD_PORTS][LCD_BITS][BIT_STATES];
250
251/*
252 * LCD protocols
253 */
254#define LCD_PROTO_PARALLEL      0
255#define LCD_PROTO_SERIAL        1
256#define LCD_PROTO_TI_DA8XX_LCD	2
257
258/*
259 * LCD character sets
260 */
261#define LCD_CHARSET_NORMAL      0
262#define LCD_CHARSET_KS0074      1
263
264/*
265 * LCD types
266 */
267#define LCD_TYPE_NONE		0
268#define LCD_TYPE_CUSTOM		1
269#define LCD_TYPE_OLD		2
270#define LCD_TYPE_KS0074		3
271#define LCD_TYPE_HANTRONIX	4
272#define LCD_TYPE_NEXCOM		5
273
274/*
275 * keypad types
276 */
277#define KEYPAD_TYPE_NONE	0
278#define KEYPAD_TYPE_OLD		1
279#define KEYPAD_TYPE_NEW		2
280#define KEYPAD_TYPE_NEXCOM	3
281
282/*
283 * panel profiles
284 */
285#define PANEL_PROFILE_CUSTOM	0
286#define PANEL_PROFILE_OLD	1
287#define PANEL_PROFILE_NEW	2
288#define PANEL_PROFILE_HANTRONIX	3
289#define PANEL_PROFILE_NEXCOM	4
290#define PANEL_PROFILE_LARGE	5
291
292/*
293 * Construct custom config from the kernel's configuration
294 */
295#define DEFAULT_PARPORT         0
296#define DEFAULT_PROFILE         PANEL_PROFILE_LARGE
297#define DEFAULT_KEYPAD_TYPE     KEYPAD_TYPE_OLD
298#define DEFAULT_LCD_TYPE        LCD_TYPE_OLD
299#define DEFAULT_LCD_HEIGHT      2
300#define DEFAULT_LCD_WIDTH       40
301#define DEFAULT_LCD_BWIDTH      40
302#define DEFAULT_LCD_HWIDTH      64
303#define DEFAULT_LCD_CHARSET     LCD_CHARSET_NORMAL
304#define DEFAULT_LCD_PROTO       LCD_PROTO_PARALLEL
305
306#define DEFAULT_LCD_PIN_E       PIN_AUTOLF
307#define DEFAULT_LCD_PIN_RS      PIN_SELECP
308#define DEFAULT_LCD_PIN_RW      PIN_INITP
309#define DEFAULT_LCD_PIN_SCL     PIN_STROBE
310#define DEFAULT_LCD_PIN_SDA     PIN_D0
311#define DEFAULT_LCD_PIN_BL      PIN_NOT_SET
312
313#ifdef CONFIG_PANEL_PARPORT
314#undef DEFAULT_PARPORT
315#define DEFAULT_PARPORT CONFIG_PANEL_PARPORT
316#endif
317
318#ifdef CONFIG_PANEL_PROFILE
319#undef DEFAULT_PROFILE
320#define DEFAULT_PROFILE CONFIG_PANEL_PROFILE
321#endif
322
323#if DEFAULT_PROFILE == 0	/* custom */
324#ifdef CONFIG_PANEL_KEYPAD
325#undef DEFAULT_KEYPAD_TYPE
326#define DEFAULT_KEYPAD_TYPE CONFIG_PANEL_KEYPAD
327#endif
328
329#ifdef CONFIG_PANEL_LCD
330#undef DEFAULT_LCD_TYPE
331#define DEFAULT_LCD_TYPE CONFIG_PANEL_LCD
332#endif
333
334#ifdef CONFIG_PANEL_LCD_HEIGHT
335#undef DEFAULT_LCD_HEIGHT
336#define DEFAULT_LCD_HEIGHT CONFIG_PANEL_LCD_HEIGHT
337#endif
338
339#ifdef CONFIG_PANEL_LCD_WIDTH
340#undef DEFAULT_LCD_WIDTH
341#define DEFAULT_LCD_WIDTH CONFIG_PANEL_LCD_WIDTH
342#endif
343
344#ifdef CONFIG_PANEL_LCD_BWIDTH
345#undef DEFAULT_LCD_BWIDTH
346#define DEFAULT_LCD_BWIDTH CONFIG_PANEL_LCD_BWIDTH
347#endif
348
349#ifdef CONFIG_PANEL_LCD_HWIDTH
350#undef DEFAULT_LCD_HWIDTH
351#define DEFAULT_LCD_HWIDTH CONFIG_PANEL_LCD_HWIDTH
352#endif
353
354#ifdef CONFIG_PANEL_LCD_CHARSET
355#undef DEFAULT_LCD_CHARSET
356#define DEFAULT_LCD_CHARSET CONFIG_PANEL_LCD_CHARSET
357#endif
358
359#ifdef CONFIG_PANEL_LCD_PROTO
360#undef DEFAULT_LCD_PROTO
361#define DEFAULT_LCD_PROTO CONFIG_PANEL_LCD_PROTO
362#endif
363
364#ifdef CONFIG_PANEL_LCD_PIN_E
365#undef DEFAULT_LCD_PIN_E
366#define DEFAULT_LCD_PIN_E CONFIG_PANEL_LCD_PIN_E
367#endif
368
369#ifdef CONFIG_PANEL_LCD_PIN_RS
370#undef DEFAULT_LCD_PIN_RS
371#define DEFAULT_LCD_PIN_RS CONFIG_PANEL_LCD_PIN_RS
372#endif
373
374#ifdef CONFIG_PANEL_LCD_PIN_RW
375#undef DEFAULT_LCD_PIN_RW
376#define DEFAULT_LCD_PIN_RW CONFIG_PANEL_LCD_PIN_RW
377#endif
378
379#ifdef CONFIG_PANEL_LCD_PIN_SCL
380#undef DEFAULT_LCD_PIN_SCL
381#define DEFAULT_LCD_PIN_SCL CONFIG_PANEL_LCD_PIN_SCL
382#endif
383
384#ifdef CONFIG_PANEL_LCD_PIN_SDA
385#undef DEFAULT_LCD_PIN_SDA
386#define DEFAULT_LCD_PIN_SDA CONFIG_PANEL_LCD_PIN_SDA
387#endif
388
389#ifdef CONFIG_PANEL_LCD_PIN_BL
390#undef DEFAULT_LCD_PIN_BL
391#define DEFAULT_LCD_PIN_BL CONFIG_PANEL_LCD_PIN_BL
392#endif
393
394#endif /* DEFAULT_PROFILE == 0 */
395
396/* global variables */
397
398/* Device single-open policy control */
399static atomic_t keypad_available = ATOMIC_INIT(1);
400
401static struct pardevice *pprt;
402
403static int keypad_initialized;
404
405static DEFINE_SPINLOCK(pprt_lock);
406static struct timer_list scan_timer;
407
408MODULE_DESCRIPTION("Generic parallel port LCD/Keypad driver");
409
410static int parport = DEFAULT_PARPORT;
411module_param(parport, int, 0000);
412MODULE_PARM_DESC(parport, "Parallel port index (0=lpt1, 1=lpt2, ...)");
413
414static int profile = DEFAULT_PROFILE;
415module_param(profile, int, 0000);
416MODULE_PARM_DESC(profile,
417		 "1=16x2 old kp; 2=serial 16x2, new kp; 3=16x2 hantronix; "
418		 "4=16x2 nexcom; default=40x2, old kp");
419
420static int keypad_type = NOT_SET;
421module_param(keypad_type, int, 0000);
422MODULE_PARM_DESC(keypad_type,
423		 "Keypad type: 0=none, 1=old 6 keys, 2=new 6+1 keys, 3=nexcom 4 keys");
424
425static int lcd_type = NOT_SET;
426module_param(lcd_type, int, 0000);
427MODULE_PARM_DESC(lcd_type,
428		 "LCD type: 0=none, 1=compiled-in, 2=old, 3=serial ks0074, 4=hantronix, 5=nexcom");
429
430static int lcd_height = NOT_SET;
431module_param(lcd_height, int, 0000);
432MODULE_PARM_DESC(lcd_height, "Number of lines on the LCD");
433
434static int lcd_width = NOT_SET;
435module_param(lcd_width, int, 0000);
436MODULE_PARM_DESC(lcd_width, "Number of columns on the LCD");
437
438static int lcd_bwidth = NOT_SET;	/* internal buffer width (usually 40) */
439module_param(lcd_bwidth, int, 0000);
440MODULE_PARM_DESC(lcd_bwidth, "Internal LCD line width (40)");
441
442static int lcd_hwidth = NOT_SET;	/* hardware buffer width (usually 64) */
443module_param(lcd_hwidth, int, 0000);
444MODULE_PARM_DESC(lcd_hwidth, "LCD line hardware address (64)");
445
446static int lcd_charset = NOT_SET;
447module_param(lcd_charset, int, 0000);
448MODULE_PARM_DESC(lcd_charset, "LCD character set: 0=standard, 1=KS0074");
449
450static int lcd_proto = NOT_SET;
451module_param(lcd_proto, int, 0000);
452MODULE_PARM_DESC(lcd_proto,
453		 "LCD communication: 0=parallel (//), 1=serial, 2=TI LCD Interface");
454
455/*
456 * These are the parallel port pins the LCD control signals are connected to.
457 * Set this to 0 if the signal is not used. Set it to its opposite value
458 * (negative) if the signal is negated. -MAXINT is used to indicate that the
459 * pin has not been explicitly specified.
460 *
461 * WARNING! no check will be performed about collisions with keypad !
462 */
463
464static int lcd_e_pin  = PIN_NOT_SET;
465module_param(lcd_e_pin, int, 0000);
466MODULE_PARM_DESC(lcd_e_pin,
467		 "# of the // port pin connected to LCD 'E' signal, with polarity (-17..17)");
468
469static int lcd_rs_pin = PIN_NOT_SET;
470module_param(lcd_rs_pin, int, 0000);
471MODULE_PARM_DESC(lcd_rs_pin,
472		 "# of the // port pin connected to LCD 'RS' signal, with polarity (-17..17)");
473
474static int lcd_rw_pin = PIN_NOT_SET;
475module_param(lcd_rw_pin, int, 0000);
476MODULE_PARM_DESC(lcd_rw_pin,
477		 "# of the // port pin connected to LCD 'RW' signal, with polarity (-17..17)");
478
479static int lcd_cl_pin = PIN_NOT_SET;
480module_param(lcd_cl_pin, int, 0000);
481MODULE_PARM_DESC(lcd_cl_pin,
482		 "# of the // port pin connected to serial LCD 'SCL' signal, with polarity (-17..17)");
483
484static int lcd_da_pin = PIN_NOT_SET;
485module_param(lcd_da_pin, int, 0000);
486MODULE_PARM_DESC(lcd_da_pin,
487		 "# of the // port pin connected to serial LCD 'SDA' signal, with polarity (-17..17)");
488
489static int lcd_bl_pin = PIN_NOT_SET;
490module_param(lcd_bl_pin, int, 0000);
491MODULE_PARM_DESC(lcd_bl_pin,
492		 "# of the // port pin connected to LCD backlight, with polarity (-17..17)");
493
494/* Deprecated module parameters - consider not using them anymore */
495
496static int lcd_enabled = NOT_SET;
497module_param(lcd_enabled, int, 0000);
498MODULE_PARM_DESC(lcd_enabled, "Deprecated option, use lcd_type instead");
499
500static int keypad_enabled = NOT_SET;
501module_param(keypad_enabled, int, 0000);
502MODULE_PARM_DESC(keypad_enabled, "Deprecated option, use keypad_type instead");
503
504/* for some LCD drivers (ks0074) we need a charset conversion table. */
505static const unsigned char lcd_char_conv_ks0074[256] = {
506	/*          0|8   1|9   2|A   3|B   4|C   5|D   6|E   7|F */
507	/* 0x00 */ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
508	/* 0x08 */ 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
509	/* 0x10 */ 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
510	/* 0x18 */ 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
511	/* 0x20 */ 0x20, 0x21, 0x22, 0x23, 0xa2, 0x25, 0x26, 0x27,
512	/* 0x28 */ 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
513	/* 0x30 */ 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
514	/* 0x38 */ 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
515	/* 0x40 */ 0xa0, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
516	/* 0x48 */ 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
517	/* 0x50 */ 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
518	/* 0x58 */ 0x58, 0x59, 0x5a, 0xfa, 0xfb, 0xfc, 0x1d, 0xc4,
519	/* 0x60 */ 0x96, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
520	/* 0x68 */ 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
521	/* 0x70 */ 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
522	/* 0x78 */ 0x78, 0x79, 0x7a, 0xfd, 0xfe, 0xff, 0xce, 0x20,
523	/* 0x80 */ 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
524	/* 0x88 */ 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
525	/* 0x90 */ 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
526	/* 0x98 */ 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
527	/* 0xA0 */ 0x20, 0x40, 0xb1, 0xa1, 0x24, 0xa3, 0xfe, 0x5f,
528	/* 0xA8 */ 0x22, 0xc8, 0x61, 0x14, 0x97, 0x2d, 0xad, 0x96,
529	/* 0xB0 */ 0x80, 0x8c, 0x82, 0x83, 0x27, 0x8f, 0x86, 0xdd,
530	/* 0xB8 */ 0x2c, 0x81, 0x6f, 0x15, 0x8b, 0x8a, 0x84, 0x60,
531	/* 0xC0 */ 0xe2, 0xe2, 0xe2, 0x5b, 0x5b, 0xae, 0xbc, 0xa9,
532	/* 0xC8 */ 0xc5, 0xbf, 0xc6, 0xf1, 0xe3, 0xe3, 0xe3, 0xe3,
533	/* 0xD0 */ 0x44, 0x5d, 0xa8, 0xe4, 0xec, 0xec, 0x5c, 0x78,
534	/* 0xD8 */ 0xab, 0xa6, 0xe5, 0x5e, 0x5e, 0xe6, 0xaa, 0xbe,
535	/* 0xE0 */ 0x7f, 0xe7, 0xaf, 0x7b, 0x7b, 0xaf, 0xbd, 0xc8,
536	/* 0xE8 */ 0xa4, 0xa5, 0xc7, 0xf6, 0xa7, 0xe8, 0x69, 0x69,
537	/* 0xF0 */ 0xed, 0x7d, 0xa8, 0xe4, 0xec, 0x5c, 0x5c, 0x25,
538	/* 0xF8 */ 0xac, 0xa6, 0xea, 0xef, 0x7e, 0xeb, 0xb2, 0x79,
539};
540
541static const char old_keypad_profile[][4][9] = {
542	{"S0", "Left\n", "Left\n", ""},
543	{"S1", "Down\n", "Down\n", ""},
544	{"S2", "Up\n", "Up\n", ""},
545	{"S3", "Right\n", "Right\n", ""},
546	{"S4", "Esc\n", "Esc\n", ""},
547	{"S5", "Ret\n", "Ret\n", ""},
548	{"", "", "", ""}
549};
550
551/* signals, press, repeat, release */
552static const char new_keypad_profile[][4][9] = {
553	{"S0", "Left\n", "Left\n", ""},
554	{"S1", "Down\n", "Down\n", ""},
555	{"S2", "Up\n", "Up\n", ""},
556	{"S3", "Right\n", "Right\n", ""},
557	{"S4s5", "", "Esc\n", "Esc\n"},
558	{"s4S5", "", "Ret\n", "Ret\n"},
559	{"S4S5", "Help\n", "", ""},
560	/* add new signals above this line */
561	{"", "", "", ""}
562};
563
564/* signals, press, repeat, release */
565static const char nexcom_keypad_profile[][4][9] = {
566	{"a-p-e-", "Down\n", "Down\n", ""},
567	{"a-p-E-", "Ret\n", "Ret\n", ""},
568	{"a-P-E-", "Esc\n", "Esc\n", ""},
569	{"a-P-e-", "Up\n", "Up\n", ""},
570	/* add new signals above this line */
571	{"", "", "", ""}
572};
573
574static const char (*keypad_profile)[4][9] = old_keypad_profile;
575
576static DECLARE_BITMAP(bits, LCD_BITS);
577
578static void lcd_get_bits(unsigned int port, int *val)
579{
580	unsigned int bit, state;
581
582	for (bit = 0; bit < LCD_BITS; bit++) {
583		state = test_bit(bit, bits) ? BIT_SET : BIT_CLR;
584		*val &= lcd_bits[port][bit][BIT_MSK];
585		*val |= lcd_bits[port][bit][state];
586	}
587}
588
589/* sets data port bits according to current signals values */
590static int set_data_bits(void)
591{
592	int val;
593
594	val = r_dtr(pprt);
595	lcd_get_bits(LCD_PORT_D, &val);
596	w_dtr(pprt, val);
597	return val;
598}
599
600/* sets ctrl port bits according to current signals values */
601static int set_ctrl_bits(void)
602{
603	int val;
604
605	val = r_ctr(pprt);
606	lcd_get_bits(LCD_PORT_C, &val);
607	w_ctr(pprt, val);
608	return val;
609}
610
611/* sets ctrl & data port bits according to current signals values */
612static void panel_set_bits(void)
613{
614	set_data_bits();
615	set_ctrl_bits();
616}
617
618/*
619 * Converts a parallel port pin (from -25 to 25) to data and control ports
620 * masks, and data and control port bits. The signal will be considered
621 * unconnected if it's on pin 0 or an invalid pin (<-25 or >25).
622 *
623 * Result will be used this way :
624 *   out(dport, in(dport) & d_val[2] | d_val[signal_state])
625 *   out(cport, in(cport) & c_val[2] | c_val[signal_state])
626 */
627static void pin_to_bits(int pin, unsigned char *d_val, unsigned char *c_val)
628{
629	int d_bit, c_bit, inv;
630
631	d_val[0] = 0;
632	c_val[0] = 0;
633	d_val[1] = 0;
634	c_val[1] = 0;
635	d_val[2] = 0xFF;
636	c_val[2] = 0xFF;
637
638	if (pin == 0)
639		return;
640
641	inv = (pin < 0);
642	if (inv)
643		pin = -pin;
644
645	d_bit = 0;
646	c_bit = 0;
647
648	switch (pin) {
649	case PIN_STROBE:	/* strobe, inverted */
650		c_bit = PNL_PSTROBE;
651		inv = !inv;
652		break;
653	case PIN_D0...PIN_D7:	/* D0 - D7 = 2 - 9 */
654		d_bit = 1 << (pin - 2);
655		break;
656	case PIN_AUTOLF:	/* autofeed, inverted */
657		c_bit = PNL_PAUTOLF;
658		inv = !inv;
659		break;
660	case PIN_INITP:		/* init, direct */
661		c_bit = PNL_PINITP;
662		break;
663	case PIN_SELECP:	/* select_in, inverted */
664		c_bit = PNL_PSELECP;
665		inv = !inv;
666		break;
667	default:		/* unknown pin, ignore */
668		break;
669	}
670
671	if (c_bit) {
672		c_val[2] &= ~c_bit;
673		c_val[!inv] = c_bit;
674	} else if (d_bit) {
675		d_val[2] &= ~d_bit;
676		d_val[!inv] = d_bit;
677	}
678}
679
680/*
681 * send a serial byte to the LCD panel. The caller is responsible for locking
682 * if needed.
683 */
684static void lcd_send_serial(int byte)
685{
686	int bit;
687
688	/*
689	 * the data bit is set on D0, and the clock on STROBE.
690	 * LCD reads D0 on STROBE's rising edge.
691	 */
692	for (bit = 0; bit < 8; bit++) {
693		clear_bit(LCD_BIT_CL, bits);	/* CLK low */
694		panel_set_bits();
695		if (byte & 1) {
696			set_bit(LCD_BIT_DA, bits);
697		} else {
698			clear_bit(LCD_BIT_DA, bits);
699		}
700
701		panel_set_bits();
702		udelay(2);  /* maintain the data during 2 us before CLK up */
703		set_bit(LCD_BIT_CL, bits);	/* CLK high */
704		panel_set_bits();
705		udelay(1);  /* maintain the strobe during 1 us */
706		byte >>= 1;
707	}
708}
709
710/* turn the backlight on or off */
711static void lcd_backlight(struct charlcd *charlcd, int on)
712{
713	if (lcd.pins.bl == PIN_NONE)
714		return;
715
716	/* The backlight is activated by setting the AUTOFEED line to +5V  */
717	spin_lock_irq(&pprt_lock);
718	if (on)
719		set_bit(LCD_BIT_BL, bits);
720	else
721		clear_bit(LCD_BIT_BL, bits);
722	panel_set_bits();
723	spin_unlock_irq(&pprt_lock);
724}
725
726/* send a command to the LCD panel in serial mode */
727static void lcd_write_cmd_s(struct charlcd *charlcd, int cmd)
728{
729	spin_lock_irq(&pprt_lock);
730	lcd_send_serial(0x1F);	/* R/W=W, RS=0 */
731	lcd_send_serial(cmd & 0x0F);
732	lcd_send_serial((cmd >> 4) & 0x0F);
733	udelay(40);		/* the shortest command takes at least 40 us */
734	spin_unlock_irq(&pprt_lock);
735}
736
737/* send data to the LCD panel in serial mode */
738static void lcd_write_data_s(struct charlcd *charlcd, int data)
739{
740	spin_lock_irq(&pprt_lock);
741	lcd_send_serial(0x5F);	/* R/W=W, RS=1 */
742	lcd_send_serial(data & 0x0F);
743	lcd_send_serial((data >> 4) & 0x0F);
744	udelay(40);		/* the shortest data takes at least 40 us */
745	spin_unlock_irq(&pprt_lock);
746}
747
748/* send a command to the LCD panel in 8 bits parallel mode */
749static void lcd_write_cmd_p8(struct charlcd *charlcd, int cmd)
750{
751	spin_lock_irq(&pprt_lock);
752	/* present the data to the data port */
753	w_dtr(pprt, cmd);
754	udelay(20);	/* maintain the data during 20 us before the strobe */
755
756	set_bit(LCD_BIT_E, bits);
757	clear_bit(LCD_BIT_RS, bits);
758	clear_bit(LCD_BIT_RW, bits);
759	set_ctrl_bits();
760
761	udelay(40);	/* maintain the strobe during 40 us */
762
763	clear_bit(LCD_BIT_E, bits);
764	set_ctrl_bits();
765
766	udelay(120);	/* the shortest command takes at least 120 us */
767	spin_unlock_irq(&pprt_lock);
768}
769
770/* send data to the LCD panel in 8 bits parallel mode */
771static void lcd_write_data_p8(struct charlcd *charlcd, int data)
772{
773	spin_lock_irq(&pprt_lock);
774	/* present the data to the data port */
775	w_dtr(pprt, data);
776	udelay(20);	/* maintain the data during 20 us before the strobe */
777
778	set_bit(LCD_BIT_E, bits);
779	set_bit(LCD_BIT_RS, bits);
780	clear_bit(LCD_BIT_RW, bits);
781	set_ctrl_bits();
782
783	udelay(40);	/* maintain the strobe during 40 us */
784
785	clear_bit(LCD_BIT_E, bits);
786	set_ctrl_bits();
787
788	udelay(45);	/* the shortest data takes at least 45 us */
789	spin_unlock_irq(&pprt_lock);
790}
791
792/* send a command to the TI LCD panel */
793static void lcd_write_cmd_tilcd(struct charlcd *charlcd, int cmd)
794{
795	spin_lock_irq(&pprt_lock);
796	/* present the data to the control port */
797	w_ctr(pprt, cmd);
798	udelay(60);
799	spin_unlock_irq(&pprt_lock);
800}
801
802/* send data to the TI LCD panel */
803static void lcd_write_data_tilcd(struct charlcd *charlcd, int data)
804{
805	spin_lock_irq(&pprt_lock);
806	/* present the data to the data port */
807	w_dtr(pprt, data);
808	udelay(60);
809	spin_unlock_irq(&pprt_lock);
810}
811
812/* fills the display with spaces and resets X/Y */
813static void lcd_clear_fast_s(struct charlcd *charlcd)
814{
815	int pos;
816
817	spin_lock_irq(&pprt_lock);
818	for (pos = 0; pos < charlcd->height * charlcd->hwidth; pos++) {
819		lcd_send_serial(0x5F);	/* R/W=W, RS=1 */
820		lcd_send_serial(' ' & 0x0F);
821		lcd_send_serial((' ' >> 4) & 0x0F);
822		/* the shortest data takes at least 40 us */
823		udelay(40);
824	}
825	spin_unlock_irq(&pprt_lock);
826}
827
828/* fills the display with spaces and resets X/Y */
829static void lcd_clear_fast_p8(struct charlcd *charlcd)
830{
831	int pos;
832
833	spin_lock_irq(&pprt_lock);
834	for (pos = 0; pos < charlcd->height * charlcd->hwidth; pos++) {
835		/* present the data to the data port */
836		w_dtr(pprt, ' ');
837
838		/* maintain the data during 20 us before the strobe */
839		udelay(20);
840
841		set_bit(LCD_BIT_E, bits);
842		set_bit(LCD_BIT_RS, bits);
843		clear_bit(LCD_BIT_RW, bits);
844		set_ctrl_bits();
845
846		/* maintain the strobe during 40 us */
847		udelay(40);
848
849		clear_bit(LCD_BIT_E, bits);
850		set_ctrl_bits();
851
852		/* the shortest data takes at least 45 us */
853		udelay(45);
854	}
855	spin_unlock_irq(&pprt_lock);
856}
857
858/* fills the display with spaces and resets X/Y */
859static void lcd_clear_fast_tilcd(struct charlcd *charlcd)
860{
861	int pos;
862
863	spin_lock_irq(&pprt_lock);
864	for (pos = 0; pos < charlcd->height * charlcd->hwidth; pos++) {
865		/* present the data to the data port */
866		w_dtr(pprt, ' ');
867		udelay(60);
868	}
869
870	spin_unlock_irq(&pprt_lock);
871}
872
873static const struct charlcd_ops charlcd_serial_ops = {
874	.write_cmd	= lcd_write_cmd_s,
875	.write_data	= lcd_write_data_s,
876	.clear_fast	= lcd_clear_fast_s,
877	.backlight	= lcd_backlight,
878};
879
880static const struct charlcd_ops charlcd_parallel_ops = {
881	.write_cmd	= lcd_write_cmd_p8,
882	.write_data	= lcd_write_data_p8,
883	.clear_fast	= lcd_clear_fast_p8,
884	.backlight	= lcd_backlight,
885};
886
887static const struct charlcd_ops charlcd_tilcd_ops = {
888	.write_cmd	= lcd_write_cmd_tilcd,
889	.write_data	= lcd_write_data_tilcd,
890	.clear_fast	= lcd_clear_fast_tilcd,
891	.backlight	= lcd_backlight,
892};
893
894/* initialize the LCD driver */
895static void lcd_init(void)
896{
897	struct charlcd *charlcd;
898
899	charlcd = charlcd_alloc(0);
900	if (!charlcd)
901		return;
902
903	/*
904	 * Init lcd struct with load-time values to preserve exact
905	 * current functionality (at least for now).
906	 */
907	charlcd->height = lcd_height;
908	charlcd->width = lcd_width;
909	charlcd->bwidth = lcd_bwidth;
910	charlcd->hwidth = lcd_hwidth;
911
912	switch (selected_lcd_type) {
913	case LCD_TYPE_OLD:
914		/* parallel mode, 8 bits */
915		lcd.proto = LCD_PROTO_PARALLEL;
916		lcd.charset = LCD_CHARSET_NORMAL;
917		lcd.pins.e = PIN_STROBE;
918		lcd.pins.rs = PIN_AUTOLF;
919
920		charlcd->width = 40;
921		charlcd->bwidth = 40;
922		charlcd->hwidth = 64;
923		charlcd->height = 2;
924		break;
925	case LCD_TYPE_KS0074:
926		/* serial mode, ks0074 */
927		lcd.proto = LCD_PROTO_SERIAL;
928		lcd.charset = LCD_CHARSET_KS0074;
929		lcd.pins.bl = PIN_AUTOLF;
930		lcd.pins.cl = PIN_STROBE;
931		lcd.pins.da = PIN_D0;
932
933		charlcd->width = 16;
934		charlcd->bwidth = 40;
935		charlcd->hwidth = 16;
936		charlcd->height = 2;
937		break;
938	case LCD_TYPE_NEXCOM:
939		/* parallel mode, 8 bits, generic */
940		lcd.proto = LCD_PROTO_PARALLEL;
941		lcd.charset = LCD_CHARSET_NORMAL;
942		lcd.pins.e = PIN_AUTOLF;
943		lcd.pins.rs = PIN_SELECP;
944		lcd.pins.rw = PIN_INITP;
945
946		charlcd->width = 16;
947		charlcd->bwidth = 40;
948		charlcd->hwidth = 64;
949		charlcd->height = 2;
950		break;
951	case LCD_TYPE_CUSTOM:
952		/* customer-defined */
953		lcd.proto = DEFAULT_LCD_PROTO;
954		lcd.charset = DEFAULT_LCD_CHARSET;
955		/* default geometry will be set later */
956		break;
957	case LCD_TYPE_HANTRONIX:
958		/* parallel mode, 8 bits, hantronix-like */
959	default:
960		lcd.proto = LCD_PROTO_PARALLEL;
961		lcd.charset = LCD_CHARSET_NORMAL;
962		lcd.pins.e = PIN_STROBE;
963		lcd.pins.rs = PIN_SELECP;
964
965		charlcd->width = 16;
966		charlcd->bwidth = 40;
967		charlcd->hwidth = 64;
968		charlcd->height = 2;
969		break;
970	}
971
972	/* Overwrite with module params set on loading */
973	if (lcd_height != NOT_SET)
974		charlcd->height = lcd_height;
975	if (lcd_width != NOT_SET)
976		charlcd->width = lcd_width;
977	if (lcd_bwidth != NOT_SET)
978		charlcd->bwidth = lcd_bwidth;
979	if (lcd_hwidth != NOT_SET)
980		charlcd->hwidth = lcd_hwidth;
981	if (lcd_charset != NOT_SET)
982		lcd.charset = lcd_charset;
983	if (lcd_proto != NOT_SET)
984		lcd.proto = lcd_proto;
985	if (lcd_e_pin != PIN_NOT_SET)
986		lcd.pins.e = lcd_e_pin;
987	if (lcd_rs_pin != PIN_NOT_SET)
988		lcd.pins.rs = lcd_rs_pin;
989	if (lcd_rw_pin != PIN_NOT_SET)
990		lcd.pins.rw = lcd_rw_pin;
991	if (lcd_cl_pin != PIN_NOT_SET)
992		lcd.pins.cl = lcd_cl_pin;
993	if (lcd_da_pin != PIN_NOT_SET)
994		lcd.pins.da = lcd_da_pin;
995	if (lcd_bl_pin != PIN_NOT_SET)
996		lcd.pins.bl = lcd_bl_pin;
997
998	/* this is used to catch wrong and default values */
999	if (charlcd->width <= 0)
1000		charlcd->width = DEFAULT_LCD_WIDTH;
1001	if (charlcd->bwidth <= 0)
1002		charlcd->bwidth = DEFAULT_LCD_BWIDTH;
1003	if (charlcd->hwidth <= 0)
1004		charlcd->hwidth = DEFAULT_LCD_HWIDTH;
1005	if (charlcd->height <= 0)
1006		charlcd->height = DEFAULT_LCD_HEIGHT;
1007
1008	if (lcd.proto == LCD_PROTO_SERIAL) {	/* SERIAL */
1009		charlcd->ops = &charlcd_serial_ops;
1010
1011		if (lcd.pins.cl == PIN_NOT_SET)
1012			lcd.pins.cl = DEFAULT_LCD_PIN_SCL;
1013		if (lcd.pins.da == PIN_NOT_SET)
1014			lcd.pins.da = DEFAULT_LCD_PIN_SDA;
1015
1016	} else if (lcd.proto == LCD_PROTO_PARALLEL) {	/* PARALLEL */
1017		charlcd->ops = &charlcd_parallel_ops;
1018
1019		if (lcd.pins.e == PIN_NOT_SET)
1020			lcd.pins.e = DEFAULT_LCD_PIN_E;
1021		if (lcd.pins.rs == PIN_NOT_SET)
1022			lcd.pins.rs = DEFAULT_LCD_PIN_RS;
1023		if (lcd.pins.rw == PIN_NOT_SET)
1024			lcd.pins.rw = DEFAULT_LCD_PIN_RW;
1025	} else {
1026		charlcd->ops = &charlcd_tilcd_ops;
1027	}
1028
1029	if (lcd.pins.bl == PIN_NOT_SET)
1030		lcd.pins.bl = DEFAULT_LCD_PIN_BL;
1031
1032	if (lcd.pins.e == PIN_NOT_SET)
1033		lcd.pins.e = PIN_NONE;
1034	if (lcd.pins.rs == PIN_NOT_SET)
1035		lcd.pins.rs = PIN_NONE;
1036	if (lcd.pins.rw == PIN_NOT_SET)
1037		lcd.pins.rw = PIN_NONE;
1038	if (lcd.pins.bl == PIN_NOT_SET)
1039		lcd.pins.bl = PIN_NONE;
1040	if (lcd.pins.cl == PIN_NOT_SET)
1041		lcd.pins.cl = PIN_NONE;
1042	if (lcd.pins.da == PIN_NOT_SET)
1043		lcd.pins.da = PIN_NONE;
1044
1045	if (lcd.charset == NOT_SET)
1046		lcd.charset = DEFAULT_LCD_CHARSET;
1047
1048	if (lcd.charset == LCD_CHARSET_KS0074)
1049		charlcd->char_conv = lcd_char_conv_ks0074;
1050	else
1051		charlcd->char_conv = NULL;
1052
1053	pin_to_bits(lcd.pins.e, lcd_bits[LCD_PORT_D][LCD_BIT_E],
1054		    lcd_bits[LCD_PORT_C][LCD_BIT_E]);
1055	pin_to_bits(lcd.pins.rs, lcd_bits[LCD_PORT_D][LCD_BIT_RS],
1056		    lcd_bits[LCD_PORT_C][LCD_BIT_RS]);
1057	pin_to_bits(lcd.pins.rw, lcd_bits[LCD_PORT_D][LCD_BIT_RW],
1058		    lcd_bits[LCD_PORT_C][LCD_BIT_RW]);
1059	pin_to_bits(lcd.pins.bl, lcd_bits[LCD_PORT_D][LCD_BIT_BL],
1060		    lcd_bits[LCD_PORT_C][LCD_BIT_BL]);
1061	pin_to_bits(lcd.pins.cl, lcd_bits[LCD_PORT_D][LCD_BIT_CL],
1062		    lcd_bits[LCD_PORT_C][LCD_BIT_CL]);
1063	pin_to_bits(lcd.pins.da, lcd_bits[LCD_PORT_D][LCD_BIT_DA],
1064		    lcd_bits[LCD_PORT_C][LCD_BIT_DA]);
1065
1066	lcd.charlcd = charlcd;
1067	lcd.initialized = true;
1068}
1069
1070/*
1071 * These are the file operation function for user access to /dev/keypad
1072 */
1073
1074static ssize_t keypad_read(struct file *file,
1075			   char __user *buf, size_t count, loff_t *ppos)
1076{
1077	unsigned i = *ppos;
1078	char __user *tmp = buf;
1079
1080	if (keypad_buflen == 0) {
1081		if (file->f_flags & O_NONBLOCK)
1082			return -EAGAIN;
1083
1084		if (wait_event_interruptible(keypad_read_wait,
1085					     keypad_buflen != 0))
1086			return -EINTR;
1087	}
1088
1089	for (; count-- > 0 && (keypad_buflen > 0);
1090	     ++i, ++tmp, --keypad_buflen) {
1091		put_user(keypad_buffer[keypad_start], tmp);
1092		keypad_start = (keypad_start + 1) % KEYPAD_BUFFER;
1093	}
1094	*ppos = i;
1095
1096	return tmp - buf;
1097}
1098
1099static int keypad_open(struct inode *inode, struct file *file)
1100{
1101	int ret;
1102
1103	ret = -EBUSY;
1104	if (!atomic_dec_and_test(&keypad_available))
1105		goto fail;	/* open only once at a time */
1106
1107	ret = -EPERM;
1108	if (file->f_mode & FMODE_WRITE)	/* device is read-only */
1109		goto fail;
1110
1111	keypad_buflen = 0;	/* flush the buffer on opening */
1112	return 0;
1113 fail:
1114	atomic_inc(&keypad_available);
1115	return ret;
1116}
1117
1118static int keypad_release(struct inode *inode, struct file *file)
1119{
1120	atomic_inc(&keypad_available);
1121	return 0;
1122}
1123
1124static const struct file_operations keypad_fops = {
1125	.read    = keypad_read,		/* read */
1126	.open    = keypad_open,		/* open */
1127	.release = keypad_release,	/* close */
1128	.llseek  = default_llseek,
1129};
1130
1131static struct miscdevice keypad_dev = {
1132	.minor	= KEYPAD_MINOR,
1133	.name	= "keypad",
1134	.fops	= &keypad_fops,
1135};
1136
1137static void keypad_send_key(const char *string, int max_len)
1138{
1139	/* send the key to the device only if a process is attached to it. */
1140	if (!atomic_read(&keypad_available)) {
1141		while (max_len-- && keypad_buflen < KEYPAD_BUFFER && *string) {
1142			keypad_buffer[(keypad_start + keypad_buflen++) %
1143				      KEYPAD_BUFFER] = *string++;
1144		}
1145		wake_up_interruptible(&keypad_read_wait);
1146	}
1147}
1148
1149/* this function scans all the bits involving at least one logical signal,
1150 * and puts the results in the bitfield "phys_read" (one bit per established
1151 * contact), and sets "phys_read_prev" to "phys_read".
1152 *
1153 * Note: to debounce input signals, we will only consider as switched a signal
1154 * which is stable across 2 measures. Signals which are different between two
1155 * reads will be kept as they previously were in their logical form (phys_prev).
1156 * A signal which has just switched will have a 1 in
1157 * (phys_read ^ phys_read_prev).
1158 */
1159static void phys_scan_contacts(void)
1160{
1161	int bit, bitval;
1162	char oldval;
1163	char bitmask;
1164	char gndmask;
1165
1166	phys_prev = phys_curr;
1167	phys_read_prev = phys_read;
1168	phys_read = 0;		/* flush all signals */
1169
1170	/* keep track of old value, with all outputs disabled */
1171	oldval = r_dtr(pprt) | scan_mask_o;
1172	/* activate all keyboard outputs (active low) */
1173	w_dtr(pprt, oldval & ~scan_mask_o);
1174
1175	/* will have a 1 for each bit set to gnd */
1176	bitmask = PNL_PINPUT(r_str(pprt)) & scan_mask_i;
1177	/* disable all matrix signals */
1178	w_dtr(pprt, oldval);
1179
1180	/* now that all outputs are cleared, the only active input bits are
1181	 * directly connected to the ground
1182	 */
1183
1184	/* 1 for each grounded input */
1185	gndmask = PNL_PINPUT(r_str(pprt)) & scan_mask_i;
1186
1187	/* grounded inputs are signals 40-44 */
1188	phys_read |= (__u64)gndmask << 40;
1189
1190	if (bitmask != gndmask) {
1191		/*
1192		 * since clearing the outputs changed some inputs, we know
1193		 * that some input signals are currently tied to some outputs.
1194		 * So we'll scan them.
1195		 */
1196		for (bit = 0; bit < 8; bit++) {
1197			bitval = BIT(bit);
1198
1199			if (!(scan_mask_o & bitval))	/* skip unused bits */
1200				continue;
1201
1202			w_dtr(pprt, oldval & ~bitval);	/* enable this output */
1203			bitmask = PNL_PINPUT(r_str(pprt)) & ~gndmask;
1204			phys_read |= (__u64)bitmask << (5 * bit);
1205		}
1206		w_dtr(pprt, oldval);	/* disable all outputs */
1207	}
1208	/*
1209	 * this is easy: use old bits when they are flapping,
1210	 * use new ones when stable
1211	 */
1212	phys_curr = (phys_prev & (phys_read ^ phys_read_prev)) |
1213		    (phys_read & ~(phys_read ^ phys_read_prev));
1214}
1215
1216static inline int input_state_high(struct logical_input *input)
1217{
1218#if 0
1219	/* FIXME:
1220	 * this is an invalid test. It tries to catch
1221	 * transitions from single-key to multiple-key, but
1222	 * doesn't take into account the contacts polarity.
1223	 * The only solution to the problem is to parse keys
1224	 * from the most complex to the simplest combinations,
1225	 * and mark them as 'caught' once a combination
1226	 * matches, then unmatch it for all other ones.
1227	 */
1228
1229	/* try to catch dangerous transitions cases :
1230	 * someone adds a bit, so this signal was a false
1231	 * positive resulting from a transition. We should
1232	 * invalidate the signal immediately and not call the
1233	 * release function.
1234	 * eg: 0 -(press A)-> A -(press B)-> AB : don't match A's release.
1235	 */
1236	if (((phys_prev & input->mask) == input->value) &&
1237	    ((phys_curr & input->mask) >  input->value)) {
1238		input->state = INPUT_ST_LOW; /* invalidate */
1239		return 1;
1240	}
1241#endif
1242
1243	if ((phys_curr & input->mask) == input->value) {
1244		if ((input->type == INPUT_TYPE_STD) &&
1245		    (input->high_timer == 0)) {
1246			input->high_timer++;
1247			if (input->u.std.press_fct)
1248				input->u.std.press_fct(input->u.std.press_data);
1249		} else if (input->type == INPUT_TYPE_KBD) {
1250			/* will turn on the light */
1251			keypressed = 1;
1252
1253			if (input->high_timer == 0) {
1254				char *press_str = input->u.kbd.press_str;
1255
1256				if (press_str[0]) {
1257					int s = sizeof(input->u.kbd.press_str);
1258
1259					keypad_send_key(press_str, s);
1260				}
1261			}
1262
1263			if (input->u.kbd.repeat_str[0]) {
1264				char *repeat_str = input->u.kbd.repeat_str;
1265
1266				if (input->high_timer >= KEYPAD_REP_START) {
1267					int s = sizeof(input->u.kbd.repeat_str);
1268
1269					input->high_timer -= KEYPAD_REP_DELAY;
1270					keypad_send_key(repeat_str, s);
1271				}
1272				/* we will need to come back here soon */
1273				inputs_stable = 0;
1274			}
1275
1276			if (input->high_timer < 255)
1277				input->high_timer++;
1278		}
1279		return 1;
1280	}
1281
1282	/* else signal falling down. Let's fall through. */
1283	input->state = INPUT_ST_FALLING;
1284	input->fall_timer = 0;
1285
1286	return 0;
1287}
1288
1289static inline void input_state_falling(struct logical_input *input)
1290{
1291#if 0
1292	/* FIXME !!! same comment as in input_state_high */
1293	if (((phys_prev & input->mask) == input->value) &&
1294	    ((phys_curr & input->mask) >  input->value)) {
1295		input->state = INPUT_ST_LOW;	/* invalidate */
1296		return;
1297	}
1298#endif
1299
1300	if ((phys_curr & input->mask) == input->value) {
1301		if (input->type == INPUT_TYPE_KBD) {
1302			/* will turn on the light */
1303			keypressed = 1;
1304
1305			if (input->u.kbd.repeat_str[0]) {
1306				char *repeat_str = input->u.kbd.repeat_str;
1307
1308				if (input->high_timer >= KEYPAD_REP_START) {
1309					int s = sizeof(input->u.kbd.repeat_str);
1310
1311					input->high_timer -= KEYPAD_REP_DELAY;
1312					keypad_send_key(repeat_str, s);
1313				}
1314				/* we will need to come back here soon */
1315				inputs_stable = 0;
1316			}
1317
1318			if (input->high_timer < 255)
1319				input->high_timer++;
1320		}
1321		input->state = INPUT_ST_HIGH;
1322	} else if (input->fall_timer >= input->fall_time) {
1323		/* call release event */
1324		if (input->type == INPUT_TYPE_STD) {
1325			void (*release_fct)(int) = input->u.std.release_fct;
1326
1327			if (release_fct)
1328				release_fct(input->u.std.release_data);
1329		} else if (input->type == INPUT_TYPE_KBD) {
1330			char *release_str = input->u.kbd.release_str;
1331
1332			if (release_str[0]) {
1333				int s = sizeof(input->u.kbd.release_str);
1334
1335				keypad_send_key(release_str, s);
1336			}
1337		}
1338
1339		input->state = INPUT_ST_LOW;
1340	} else {
1341		input->fall_timer++;
1342		inputs_stable = 0;
1343	}
1344}
1345
1346static void panel_process_inputs(void)
1347{
1348	struct logical_input *input;
1349
1350	keypressed = 0;
1351	inputs_stable = 1;
1352	list_for_each_entry(input, &logical_inputs, list) {
1353		switch (input->state) {
1354		case INPUT_ST_LOW:
1355			if ((phys_curr & input->mask) != input->value)
1356				break;
1357			/* if all needed ones were already set previously,
1358			 * this means that this logical signal has been
1359			 * activated by the releasing of another combined
1360			 * signal, so we don't want to match.
1361			 * eg: AB -(release B)-> A -(release A)-> 0 :
1362			 *     don't match A.
1363			 */
1364			if ((phys_prev & input->mask) == input->value)
1365				break;
1366			input->rise_timer = 0;
1367			input->state = INPUT_ST_RISING;
1368			fallthrough;
1369		case INPUT_ST_RISING:
1370			if ((phys_curr & input->mask) != input->value) {
1371				input->state = INPUT_ST_LOW;
1372				break;
1373			}
1374			if (input->rise_timer < input->rise_time) {
1375				inputs_stable = 0;
1376				input->rise_timer++;
1377				break;
1378			}
1379			input->high_timer = 0;
1380			input->state = INPUT_ST_HIGH;
1381			fallthrough;
1382		case INPUT_ST_HIGH:
1383			if (input_state_high(input))
1384				break;
1385			fallthrough;
1386		case INPUT_ST_FALLING:
1387			input_state_falling(input);
1388		}
1389	}
1390}
1391
1392static void panel_scan_timer(struct timer_list *unused)
1393{
1394	if (keypad.enabled && keypad_initialized) {
1395		if (spin_trylock_irq(&pprt_lock)) {
1396			phys_scan_contacts();
1397
1398			/* no need for the parport anymore */
1399			spin_unlock_irq(&pprt_lock);
1400		}
1401
1402		if (!inputs_stable || phys_curr != phys_prev)
1403			panel_process_inputs();
1404	}
1405
1406	if (keypressed && lcd.enabled && lcd.initialized)
1407		charlcd_poke(lcd.charlcd);
1408
1409	mod_timer(&scan_timer, jiffies + INPUT_POLL_TIME);
1410}
1411
1412static void init_scan_timer(void)
1413{
1414	if (scan_timer.function)
1415		return;		/* already started */
1416
1417	timer_setup(&scan_timer, panel_scan_timer, 0);
1418	scan_timer.expires = jiffies + INPUT_POLL_TIME;
1419	add_timer(&scan_timer);
1420}
1421
1422/* converts a name of the form "({BbAaPpSsEe}{01234567-})*" to a series of bits.
1423 * if <omask> or <imask> are non-null, they will be or'ed with the bits
1424 * corresponding to out and in bits respectively.
1425 * returns 1 if ok, 0 if error (in which case, nothing is written).
1426 */
1427static u8 input_name2mask(const char *name, __u64 *mask, __u64 *value,
1428			  u8 *imask, u8 *omask)
1429{
1430	const char sigtab[] = "EeSsPpAaBb";
1431	u8 im, om;
1432	__u64 m, v;
1433
1434	om = 0;
1435	im = 0;
1436	m = 0ULL;
1437	v = 0ULL;
1438	while (*name) {
1439		int in, out, bit, neg;
1440		const char *idx;
1441
1442		idx = strchr(sigtab, *name);
1443		if (!idx)
1444			return 0;	/* input name not found */
1445
1446		in = idx - sigtab;
1447		neg = (in & 1);	/* odd (lower) names are negated */
1448		in >>= 1;
1449		im |= BIT(in);
1450
1451		name++;
1452		if (*name >= '0' && *name <= '7') {
1453			out = *name - '0';
1454			om |= BIT(out);
1455		} else if (*name == '-') {
1456			out = 8;
1457		} else {
1458			return 0;	/* unknown bit name */
1459		}
1460
1461		bit = (out * 5) + in;
1462
1463		m |= 1ULL << bit;
1464		if (!neg)
1465			v |= 1ULL << bit;
1466		name++;
1467	}
1468	*mask = m;
1469	*value = v;
1470	if (imask)
1471		*imask |= im;
1472	if (omask)
1473		*omask |= om;
1474	return 1;
1475}
1476
1477/* tries to bind a key to the signal name <name>. The key will send the
1478 * strings <press>, <repeat>, <release> for these respective events.
1479 * Returns the pointer to the new key if ok, NULL if the key could not be bound.
1480 */
1481static struct logical_input *panel_bind_key(const char *name, const char *press,
1482					    const char *repeat,
1483					    const char *release)
1484{
1485	struct logical_input *key;
1486
1487	key = kzalloc(sizeof(*key), GFP_KERNEL);
1488	if (!key)
1489		return NULL;
1490
1491	if (!input_name2mask(name, &key->mask, &key->value, &scan_mask_i,
1492			     &scan_mask_o)) {
1493		kfree(key);
1494		return NULL;
1495	}
1496
1497	key->type = INPUT_TYPE_KBD;
1498	key->state = INPUT_ST_LOW;
1499	key->rise_time = 1;
1500	key->fall_time = 1;
1501
1502	strncpy(key->u.kbd.press_str, press, sizeof(key->u.kbd.press_str));
1503	strncpy(key->u.kbd.repeat_str, repeat, sizeof(key->u.kbd.repeat_str));
1504	strncpy(key->u.kbd.release_str, release,
1505		sizeof(key->u.kbd.release_str));
1506	list_add(&key->list, &logical_inputs);
1507	return key;
1508}
1509
1510#if 0
1511/* tries to bind a callback function to the signal name <name>. The function
1512 * <press_fct> will be called with the <press_data> arg when the signal is
1513 * activated, and so on for <release_fct>/<release_data>
1514 * Returns the pointer to the new signal if ok, NULL if the signal could not
1515 * be bound.
1516 */
1517static struct logical_input *panel_bind_callback(char *name,
1518						 void (*press_fct)(int),
1519						 int press_data,
1520						 void (*release_fct)(int),
1521						 int release_data)
1522{
1523	struct logical_input *callback;
1524
1525	callback = kmalloc(sizeof(*callback), GFP_KERNEL);
1526	if (!callback)
1527		return NULL;
1528
1529	memset(callback, 0, sizeof(struct logical_input));
1530	if (!input_name2mask(name, &callback->mask, &callback->value,
1531			     &scan_mask_i, &scan_mask_o))
1532		return NULL;
1533
1534	callback->type = INPUT_TYPE_STD;
1535	callback->state = INPUT_ST_LOW;
1536	callback->rise_time = 1;
1537	callback->fall_time = 1;
1538	callback->u.std.press_fct = press_fct;
1539	callback->u.std.press_data = press_data;
1540	callback->u.std.release_fct = release_fct;
1541	callback->u.std.release_data = release_data;
1542	list_add(&callback->list, &logical_inputs);
1543	return callback;
1544}
1545#endif
1546
1547static void keypad_init(void)
1548{
1549	int keynum;
1550
1551	init_waitqueue_head(&keypad_read_wait);
1552	keypad_buflen = 0;	/* flushes any eventual noisy keystroke */
1553
1554	/* Let's create all known keys */
1555
1556	for (keynum = 0; keypad_profile[keynum][0][0]; keynum++) {
1557		panel_bind_key(keypad_profile[keynum][0],
1558			       keypad_profile[keynum][1],
1559			       keypad_profile[keynum][2],
1560			       keypad_profile[keynum][3]);
1561	}
1562
1563	init_scan_timer();
1564	keypad_initialized = 1;
1565}
1566
1567/**************************************************/
1568/* device initialization                          */
1569/**************************************************/
1570
1571static void panel_attach(struct parport *port)
1572{
1573	struct pardev_cb panel_cb;
1574
1575	if (port->number != parport)
1576		return;
1577
1578	if (pprt) {
1579		pr_err("%s: port->number=%d parport=%d, already registered!\n",
1580		       __func__, port->number, parport);
1581		return;
1582	}
1583
1584	memset(&panel_cb, 0, sizeof(panel_cb));
1585	panel_cb.private = &pprt;
1586	/* panel_cb.flags = 0 should be PARPORT_DEV_EXCL? */
1587
1588	pprt = parport_register_dev_model(port, "panel", &panel_cb, 0);
1589	if (!pprt) {
1590		pr_err("%s: port->number=%d parport=%d, parport_register_device() failed\n",
1591		       __func__, port->number, parport);
1592		return;
1593	}
1594
1595	if (parport_claim(pprt)) {
1596		pr_err("could not claim access to parport%d. Aborting.\n",
1597		       parport);
1598		goto err_unreg_device;
1599	}
1600
1601	/* must init LCD first, just in case an IRQ from the keypad is
1602	 * generated at keypad init
1603	 */
1604	if (lcd.enabled) {
1605		lcd_init();
1606		if (!lcd.charlcd || charlcd_register(lcd.charlcd))
1607			goto err_unreg_device;
1608	}
1609
1610	if (keypad.enabled) {
1611		keypad_init();
1612		if (misc_register(&keypad_dev))
1613			goto err_lcd_unreg;
1614	}
1615	return;
1616
1617err_lcd_unreg:
1618	if (scan_timer.function)
1619		del_timer_sync(&scan_timer);
1620	if (lcd.enabled)
1621		charlcd_unregister(lcd.charlcd);
1622err_unreg_device:
1623	charlcd_free(lcd.charlcd);
1624	lcd.charlcd = NULL;
1625	parport_unregister_device(pprt);
1626	pprt = NULL;
1627}
1628
1629static void panel_detach(struct parport *port)
1630{
1631	if (port->number != parport)
1632		return;
1633
1634	if (!pprt) {
1635		pr_err("%s: port->number=%d parport=%d, nothing to unregister.\n",
1636		       __func__, port->number, parport);
1637		return;
1638	}
1639	if (scan_timer.function)
1640		del_timer_sync(&scan_timer);
1641
1642	if (keypad.enabled) {
1643		misc_deregister(&keypad_dev);
1644		keypad_initialized = 0;
1645	}
1646
1647	if (lcd.enabled) {
1648		charlcd_unregister(lcd.charlcd);
1649		lcd.initialized = false;
1650		charlcd_free(lcd.charlcd);
1651		lcd.charlcd = NULL;
1652	}
1653
1654	/* TODO: free all input signals */
1655	parport_release(pprt);
1656	parport_unregister_device(pprt);
1657	pprt = NULL;
1658}
1659
1660static struct parport_driver panel_driver = {
1661	.name = "panel",
1662	.match_port = panel_attach,
1663	.detach = panel_detach,
1664	.devmodel = true,
1665};
1666
1667/* init function */
1668static int __init panel_init_module(void)
1669{
1670	int selected_keypad_type = NOT_SET, err;
1671
1672	/* take care of an eventual profile */
1673	switch (profile) {
1674	case PANEL_PROFILE_CUSTOM:
1675		/* custom profile */
1676		selected_keypad_type = DEFAULT_KEYPAD_TYPE;
1677		selected_lcd_type = DEFAULT_LCD_TYPE;
1678		break;
1679	case PANEL_PROFILE_OLD:
1680		/* 8 bits, 2*16, old keypad */
1681		selected_keypad_type = KEYPAD_TYPE_OLD;
1682		selected_lcd_type = LCD_TYPE_OLD;
1683
1684		/* TODO: This two are a little hacky, sort it out later */
1685		if (lcd_width == NOT_SET)
1686			lcd_width = 16;
1687		if (lcd_hwidth == NOT_SET)
1688			lcd_hwidth = 16;
1689		break;
1690	case PANEL_PROFILE_NEW:
1691		/* serial, 2*16, new keypad */
1692		selected_keypad_type = KEYPAD_TYPE_NEW;
1693		selected_lcd_type = LCD_TYPE_KS0074;
1694		break;
1695	case PANEL_PROFILE_HANTRONIX:
1696		/* 8 bits, 2*16 hantronix-like, no keypad */
1697		selected_keypad_type = KEYPAD_TYPE_NONE;
1698		selected_lcd_type = LCD_TYPE_HANTRONIX;
1699		break;
1700	case PANEL_PROFILE_NEXCOM:
1701		/* generic 8 bits, 2*16, nexcom keypad, eg. Nexcom. */
1702		selected_keypad_type = KEYPAD_TYPE_NEXCOM;
1703		selected_lcd_type = LCD_TYPE_NEXCOM;
1704		break;
1705	case PANEL_PROFILE_LARGE:
1706		/* 8 bits, 2*40, old keypad */
1707		selected_keypad_type = KEYPAD_TYPE_OLD;
1708		selected_lcd_type = LCD_TYPE_OLD;
1709		break;
1710	}
1711
1712	/*
1713	 * Overwrite selection with module param values (both keypad and lcd),
1714	 * where the deprecated params have lower prio.
1715	 */
1716	if (keypad_enabled != NOT_SET)
1717		selected_keypad_type = keypad_enabled;
1718	if (keypad_type != NOT_SET)
1719		selected_keypad_type = keypad_type;
1720
1721	keypad.enabled = (selected_keypad_type > 0);
1722
1723	if (lcd_enabled != NOT_SET)
1724		selected_lcd_type = lcd_enabled;
1725	if (lcd_type != NOT_SET)
1726		selected_lcd_type = lcd_type;
1727
1728	lcd.enabled = (selected_lcd_type > 0);
1729
1730	if (lcd.enabled) {
1731		/*
1732		 * Init lcd struct with load-time values to preserve exact
1733		 * current functionality (at least for now).
1734		 */
1735		lcd.charset = lcd_charset;
1736		lcd.proto = lcd_proto;
1737		lcd.pins.e = lcd_e_pin;
1738		lcd.pins.rs = lcd_rs_pin;
1739		lcd.pins.rw = lcd_rw_pin;
1740		lcd.pins.cl = lcd_cl_pin;
1741		lcd.pins.da = lcd_da_pin;
1742		lcd.pins.bl = lcd_bl_pin;
1743	}
1744
1745	switch (selected_keypad_type) {
1746	case KEYPAD_TYPE_OLD:
1747		keypad_profile = old_keypad_profile;
1748		break;
1749	case KEYPAD_TYPE_NEW:
1750		keypad_profile = new_keypad_profile;
1751		break;
1752	case KEYPAD_TYPE_NEXCOM:
1753		keypad_profile = nexcom_keypad_profile;
1754		break;
1755	default:
1756		keypad_profile = NULL;
1757		break;
1758	}
1759
1760	if (!lcd.enabled && !keypad.enabled) {
1761		/* no device enabled, let's exit */
1762		pr_err("panel driver disabled.\n");
1763		return -ENODEV;
1764	}
1765
1766	err = parport_register_driver(&panel_driver);
1767	if (err) {
1768		pr_err("could not register with parport. Aborting.\n");
1769		return err;
1770	}
1771
1772	if (pprt)
1773		pr_info("panel driver registered on parport%d (io=0x%lx).\n",
1774			parport, pprt->port->base);
1775	else
1776		pr_info("panel driver not yet registered\n");
1777	return 0;
1778}
1779
1780static void __exit panel_cleanup_module(void)
1781{
1782	parport_unregister_driver(&panel_driver);
1783}
1784
1785module_init(panel_init_module);
1786module_exit(panel_cleanup_module);
1787MODULE_AUTHOR("Willy Tarreau");
1788MODULE_LICENSE("GPL");
1789
1790/*
1791 * Local variables:
1792 *  c-indent-level: 4
1793 *  tab-width: 8
1794 * End:
1795 */
1796