Linux Audio

Check our new training course

Loading...
Note: File does not exist in v3.1.
   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	struct pardev_cb panel_cb;
1523
1524	if (port->number != parport)
1525		return;
1526
1527	if (pprt) {
1528		pr_err("%s: port->number=%d parport=%d, already registered!\n",
1529		       __func__, port->number, parport);
1530		return;
1531	}
1532
1533	memset(&panel_cb, 0, sizeof(panel_cb));
1534	panel_cb.private = &pprt;
1535	/* panel_cb.flags = 0 should be PARPORT_DEV_EXCL? */
1536
1537	pprt = parport_register_dev_model(port, "panel", &panel_cb, 0);
1538	if (!pprt) {
1539		pr_err("%s: port->number=%d parport=%d, parport_register_device() failed\n",
1540		       __func__, port->number, parport);
1541		return;
1542	}
1543
1544	if (parport_claim(pprt)) {
1545		pr_err("could not claim access to parport%d. Aborting.\n",
1546		       parport);
1547		goto err_unreg_device;
1548	}
1549
1550	/* must init LCD first, just in case an IRQ from the keypad is
1551	 * generated at keypad init
1552	 */
1553	if (lcd.enabled) {
1554		lcd_init();
1555		if (!lcd.charlcd || charlcd_register(lcd.charlcd))
1556			goto err_unreg_device;
1557	}
1558
1559	if (keypad.enabled) {
1560		keypad_init();
1561		if (misc_register(&keypad_dev))
1562			goto err_lcd_unreg;
1563	}
1564	return;
1565
1566err_lcd_unreg:
1567	if (scan_timer.function)
1568		del_timer_sync(&scan_timer);
1569	if (lcd.enabled)
1570		charlcd_unregister(lcd.charlcd);
1571err_unreg_device:
1572	kfree(lcd.charlcd);
1573	lcd.charlcd = NULL;
1574	parport_unregister_device(pprt);
1575	pprt = NULL;
1576}
1577
1578static void panel_detach(struct parport *port)
1579{
1580	if (port->number != parport)
1581		return;
1582
1583	if (!pprt) {
1584		pr_err("%s: port->number=%d parport=%d, nothing to unregister.\n",
1585		       __func__, port->number, parport);
1586		return;
1587	}
1588	if (scan_timer.function)
1589		del_timer_sync(&scan_timer);
1590
1591	if (keypad.enabled) {
1592		misc_deregister(&keypad_dev);
1593		keypad_initialized = 0;
1594	}
1595
1596	if (lcd.enabled) {
1597		charlcd_unregister(lcd.charlcd);
1598		lcd.initialized = false;
1599		kfree(lcd.charlcd->drvdata);
1600		kfree(lcd.charlcd);
1601		lcd.charlcd = NULL;
1602	}
1603
1604	/* TODO: free all input signals */
1605	parport_release(pprt);
1606	parport_unregister_device(pprt);
1607	pprt = NULL;
1608}
1609
1610static struct parport_driver panel_driver = {
1611	.name = "panel",
1612	.match_port = panel_attach,
1613	.detach = panel_detach,
1614	.devmodel = true,
1615};
1616
1617/* init function */
1618static int __init panel_init_module(void)
1619{
1620	int selected_keypad_type = NOT_SET, err;
1621
1622	/* take care of an eventual profile */
1623	switch (profile) {
1624	case PANEL_PROFILE_CUSTOM:
1625		/* custom profile */
1626		selected_keypad_type = DEFAULT_KEYPAD_TYPE;
1627		selected_lcd_type = DEFAULT_LCD_TYPE;
1628		break;
1629	case PANEL_PROFILE_OLD:
1630		/* 8 bits, 2*16, old keypad */
1631		selected_keypad_type = KEYPAD_TYPE_OLD;
1632		selected_lcd_type = LCD_TYPE_OLD;
1633
1634		/* TODO: This two are a little hacky, sort it out later */
1635		if (lcd_width == NOT_SET)
1636			lcd_width = 16;
1637		if (lcd_hwidth == NOT_SET)
1638			lcd_hwidth = 16;
1639		break;
1640	case PANEL_PROFILE_NEW:
1641		/* serial, 2*16, new keypad */
1642		selected_keypad_type = KEYPAD_TYPE_NEW;
1643		selected_lcd_type = LCD_TYPE_KS0074;
1644		break;
1645	case PANEL_PROFILE_HANTRONIX:
1646		/* 8 bits, 2*16 hantronix-like, no keypad */
1647		selected_keypad_type = KEYPAD_TYPE_NONE;
1648		selected_lcd_type = LCD_TYPE_HANTRONIX;
1649		break;
1650	case PANEL_PROFILE_NEXCOM:
1651		/* generic 8 bits, 2*16, nexcom keypad, eg. Nexcom. */
1652		selected_keypad_type = KEYPAD_TYPE_NEXCOM;
1653		selected_lcd_type = LCD_TYPE_NEXCOM;
1654		break;
1655	case PANEL_PROFILE_LARGE:
1656		/* 8 bits, 2*40, old keypad */
1657		selected_keypad_type = KEYPAD_TYPE_OLD;
1658		selected_lcd_type = LCD_TYPE_OLD;
1659		break;
1660	}
1661
1662	/*
1663	 * Overwrite selection with module param values (both keypad and lcd),
1664	 * where the deprecated params have lower prio.
1665	 */
1666	if (keypad_enabled != NOT_SET)
1667		selected_keypad_type = keypad_enabled;
1668	if (keypad_type != NOT_SET)
1669		selected_keypad_type = keypad_type;
1670
1671	keypad.enabled = (selected_keypad_type > 0);
1672
1673	if (lcd_enabled != NOT_SET)
1674		selected_lcd_type = lcd_enabled;
1675	if (lcd_type != NOT_SET)
1676		selected_lcd_type = lcd_type;
1677
1678	lcd.enabled = (selected_lcd_type > 0);
1679
1680	if (lcd.enabled) {
1681		/*
1682		 * Init lcd struct with load-time values to preserve exact
1683		 * current functionality (at least for now).
1684		 */
1685		lcd.charset = lcd_charset;
1686		lcd.proto = lcd_proto;
1687		lcd.pins.e = lcd_e_pin;
1688		lcd.pins.rs = lcd_rs_pin;
1689		lcd.pins.rw = lcd_rw_pin;
1690		lcd.pins.cl = lcd_cl_pin;
1691		lcd.pins.da = lcd_da_pin;
1692		lcd.pins.bl = lcd_bl_pin;
1693	}
1694
1695	switch (selected_keypad_type) {
1696	case KEYPAD_TYPE_OLD:
1697		keypad_profile = old_keypad_profile;
1698		break;
1699	case KEYPAD_TYPE_NEW:
1700		keypad_profile = new_keypad_profile;
1701		break;
1702	case KEYPAD_TYPE_NEXCOM:
1703		keypad_profile = nexcom_keypad_profile;
1704		break;
1705	default:
1706		keypad_profile = NULL;
1707		break;
1708	}
1709
1710	if (!lcd.enabled && !keypad.enabled) {
1711		/* no device enabled, let's exit */
1712		pr_err("panel driver disabled.\n");
1713		return -ENODEV;
1714	}
1715
1716	err = parport_register_driver(&panel_driver);
1717	if (err) {
1718		pr_err("could not register with parport. Aborting.\n");
1719		return err;
1720	}
1721
1722	if (pprt)
1723		pr_info("panel driver registered on parport%d (io=0x%lx).\n",
1724			parport, pprt->port->base);
1725	else
1726		pr_info("panel driver not yet registered\n");
1727	return 0;
1728}
1729
1730static void __exit panel_cleanup_module(void)
1731{
1732	parport_unregister_driver(&panel_driver);
1733}
1734
1735module_init(panel_init_module);
1736module_exit(panel_cleanup_module);
1737MODULE_AUTHOR("Willy Tarreau");
1738MODULE_LICENSE("GPL");