xref: /openbmc/linux/arch/m68k/atari/atakeyb.c (revision df561f66)
1 /*
2  * Atari Keyboard driver for 680x0 Linux
3  *
4  * This file is subject to the terms and conditions of the GNU General Public
5  * License.  See the file COPYING in the main directory of this archive
6  * for more details.
7  */
8 
9 /*
10  * Atari support by Robert de Vries
11  * enhanced by Bjoern Brauel and Roman Hodek
12  *
13  * 2.6 and input cleanup (removed autorepeat stuff) for 2.6.21
14  * 06/07 Michael Schmitz
15  */
16 
17 #include <linux/module.h>
18 #include <linux/sched.h>
19 #include <linux/kernel.h>
20 #include <linux/interrupt.h>
21 #include <linux/errno.h>
22 #include <linux/keyboard.h>
23 #include <linux/delay.h>
24 #include <linux/timer.h>
25 #include <linux/kd.h>
26 #include <linux/random.h>
27 #include <linux/init.h>
28 #include <linux/kbd_kern.h>
29 
30 #include <asm/atariints.h>
31 #include <asm/atarihw.h>
32 #include <asm/atarikb.h>
33 #include <asm/atari_joystick.h>
34 #include <asm/irq.h>
35 
36 
37 /* Hook for MIDI serial driver */
38 void (*atari_MIDI_interrupt_hook) (void);
39 /* Hook for keyboard inputdev  driver */
40 void (*atari_input_keyboard_interrupt_hook) (unsigned char, char);
41 /* Hook for mouse inputdev  driver */
42 void (*atari_input_mouse_interrupt_hook) (char *);
43 EXPORT_SYMBOL(atari_input_keyboard_interrupt_hook);
44 EXPORT_SYMBOL(atari_input_mouse_interrupt_hook);
45 
46 /* variables for IKBD self test: */
47 
48 /* state: 0: off; >0: in progress; >1: 0xf1 received */
49 static volatile int ikbd_self_test;
50 /* timestamp when last received a char */
51 static volatile unsigned long self_test_last_rcv;
52 /* bitmap of keys reported as broken */
53 static unsigned long broken_keys[128/(sizeof(unsigned long)*8)] = { 0, };
54 
55 #define BREAK_MASK	(0x80)
56 
57 /*
58  * ++roman: The following changes were applied manually:
59  *
60  *  - The Alt (= Meta) key works in combination with Shift and
61  *    Control, e.g. Alt+Shift+a sends Meta-A (0xc1), Alt+Control+A sends
62  *    Meta-Ctrl-A (0x81) ...
63  *
64  *  - The parentheses on the keypad send '(' and ')' with all
65  *    modifiers (as would do e.g. keypad '+'), but they cannot be used as
66  *    application keys (i.e. sending Esc O c).
67  *
68  *  - HELP and UNDO are mapped to be F21 and F24, resp, that send the
69  *    codes "\E[M" and "\E[P". (This is better than the old mapping to
70  *    F11 and F12, because these codes are on Shift+F1/2 anyway.) This
71  *    way, applications that allow their own keyboard mappings
72  *    (e.g. tcsh, X Windows) can be configured to use them in the way
73  *    the label suggests (providing help or undoing).
74  *
75  *  - Console switching is done with Alt+Fx (consoles 1..10) and
76  *    Shift+Alt+Fx (consoles 11..20).
77  *
78  *  - The misc. special function implemented in the kernel are mapped
79  *    to the following key combinations:
80  *
81  *      ClrHome          -> Home/Find
82  *      Shift + ClrHome  -> End/Select
83  *      Shift + Up       -> Page Up
84  *      Shift + Down     -> Page Down
85  *      Alt + Help       -> show system status
86  *      Shift + Help     -> show memory info
87  *      Ctrl + Help      -> show registers
88  *      Ctrl + Alt + Del -> Reboot
89  *      Alt + Undo       -> switch to last console
90  *      Shift + Undo     -> send interrupt
91  *      Alt + Insert     -> stop/start output (same as ^S/^Q)
92  *      Alt + Up         -> Scroll back console (if implemented)
93  *      Alt + Down       -> Scroll forward console (if implemented)
94  *      Alt + CapsLock   -> NumLock
95  *
96  * ++Andreas:
97  *
98  *  - Help mapped to K_HELP
99  *  - Undo mapped to K_UNDO (= K_F246)
100  *  - Keypad Left/Right Parenthesis mapped to new K_PPAREN[LR]
101  */
102 
103 typedef enum kb_state_t {
104 	KEYBOARD, AMOUSE, RMOUSE, JOYSTICK, CLOCK, RESYNC
105 } KB_STATE_T;
106 
107 #define	IS_SYNC_CODE(sc)	((sc) >= 0x04 && (sc) <= 0xfb)
108 
109 typedef struct keyboard_state {
110 	unsigned char buf[6];
111 	int len;
112 	KB_STATE_T state;
113 } KEYBOARD_STATE;
114 
115 KEYBOARD_STATE kb_state;
116 
117 /* ++roman: If a keyboard overrun happened, we can't tell in general how much
118  * bytes have been lost and in which state of the packet structure we are now.
119  * This usually causes keyboards bytes to be interpreted as mouse movements
120  * and vice versa, which is very annoying. It seems better to throw away some
121  * bytes (that are usually mouse bytes) than to misinterpret them. Therefore I
122  * introduced the RESYNC state for IKBD data. In this state, the bytes up to
123  * one that really looks like a key event (0x04..0xf2) or the start of a mouse
124  * packet (0xf8..0xfb) are thrown away, but at most 2 bytes. This at least
125  * speeds up the resynchronization of the event structure, even if maybe a
126  * mouse movement is lost. However, nothing is perfect. For bytes 0x01..0x03,
127  * it's really hard to decide whether they're mouse or keyboard bytes. Since
128  * overruns usually occur when moving the Atari mouse rapidly, they're seen as
129  * mouse bytes here. If this is wrong, only a make code of the keyboard gets
130  * lost, which isn't too bad. Losing a break code would be disastrous,
131  * because then the keyboard repeat strikes...
132  */
133 
atari_keyboard_interrupt(int irq,void * dummy)134 static irqreturn_t atari_keyboard_interrupt(int irq, void *dummy)
135 {
136 	u_char acia_stat;
137 	int scancode;
138 	int break_flag;
139 
140 repeat:
141 	if (acia.mid_ctrl & ACIA_IRQ)
142 		if (atari_MIDI_interrupt_hook)
143 			atari_MIDI_interrupt_hook();
144 	acia_stat = acia.key_ctrl;
145 	/* check out if the interrupt came from this ACIA */
146 	if (!((acia_stat | acia.mid_ctrl) & ACIA_IRQ))
147 		return IRQ_HANDLED;
148 
149 	if (acia_stat & ACIA_OVRN) {
150 		/* a very fast typist or a slow system, give a warning */
151 		/* ...happens often if interrupts were disabled for too long */
152 		pr_debug("Keyboard overrun\n");
153 		scancode = acia.key_data;
154 		if (ikbd_self_test)
155 			/* During self test, don't do resyncing, just process the code */
156 			goto interpret_scancode;
157 		else if (IS_SYNC_CODE(scancode)) {
158 			/* This code seem already to be the start of a new packet or a
159 			 * single scancode */
160 			kb_state.state = KEYBOARD;
161 			goto interpret_scancode;
162 		} else {
163 			/* Go to RESYNC state and skip this byte */
164 			kb_state.state = RESYNC;
165 			kb_state.len = 1;	/* skip max. 1 another byte */
166 			goto repeat;
167 		}
168 	}
169 
170 	if (acia_stat & ACIA_RDRF) {
171 		/* received a character */
172 		scancode = acia.key_data;	/* get it or reset the ACIA, I'll get it! */
173 	interpret_scancode:
174 		switch (kb_state.state) {
175 		case KEYBOARD:
176 			switch (scancode) {
177 			case 0xF7:
178 				kb_state.state = AMOUSE;
179 				kb_state.len = 0;
180 				break;
181 
182 			case 0xF8:
183 			case 0xF9:
184 			case 0xFA:
185 			case 0xFB:
186 				kb_state.state = RMOUSE;
187 				kb_state.len = 1;
188 				kb_state.buf[0] = scancode;
189 				break;
190 
191 			case 0xFC:
192 				kb_state.state = CLOCK;
193 				kb_state.len = 0;
194 				break;
195 
196 			case 0xFE:
197 			case 0xFF:
198 				kb_state.state = JOYSTICK;
199 				kb_state.len = 1;
200 				kb_state.buf[0] = scancode;
201 				break;
202 
203 			case 0xF1:
204 				/* during self-test, note that 0xf1 received */
205 				if (ikbd_self_test) {
206 					++ikbd_self_test;
207 					self_test_last_rcv = jiffies;
208 					break;
209 				}
210 				fallthrough;
211 
212 			default:
213 				break_flag = scancode & BREAK_MASK;
214 				scancode &= ~BREAK_MASK;
215 				if (ikbd_self_test) {
216 					/* Scancodes sent during the self-test stand for broken
217 					 * keys (keys being down). The code *should* be a break
218 					 * code, but nevertheless some AT keyboard interfaces send
219 					 * make codes instead. Therefore, simply ignore
220 					 * break_flag...
221 					 */
222 					int keyval, keytyp;
223 
224 					set_bit(scancode, broken_keys);
225 					self_test_last_rcv = jiffies;
226 					/* new Linux scancodes; approx. */
227 					keyval = scancode;
228 					keytyp = KTYP(keyval) - 0xf0;
229 					keyval = KVAL(keyval);
230 
231 					pr_warn("Key with scancode %d ", scancode);
232 					if (keytyp == KT_LATIN || keytyp == KT_LETTER) {
233 						if (keyval < ' ')
234 							pr_cont("('^%c') ", keyval + '@');
235 						else
236 							pr_cont("('%c') ", keyval);
237 					}
238 					pr_cont("is broken -- will be ignored.\n");
239 					break;
240 				} else if (test_bit(scancode, broken_keys))
241 					break;
242 
243 				if (atari_input_keyboard_interrupt_hook)
244 					atari_input_keyboard_interrupt_hook((unsigned char)scancode, !break_flag);
245 				break;
246 			}
247 			break;
248 
249 		case AMOUSE:
250 			kb_state.buf[kb_state.len++] = scancode;
251 			if (kb_state.len == 5) {
252 				kb_state.state = KEYBOARD;
253 				/* not yet used */
254 				/* wake up someone waiting for this */
255 			}
256 			break;
257 
258 		case RMOUSE:
259 			kb_state.buf[kb_state.len++] = scancode;
260 			if (kb_state.len == 3) {
261 				kb_state.state = KEYBOARD;
262 				if (atari_input_mouse_interrupt_hook)
263 					atari_input_mouse_interrupt_hook(kb_state.buf);
264 			}
265 			break;
266 
267 		case JOYSTICK:
268 			kb_state.buf[1] = scancode;
269 			kb_state.state = KEYBOARD;
270 #ifdef FIXED_ATARI_JOYSTICK
271 			atari_joystick_interrupt(kb_state.buf);
272 #endif
273 			break;
274 
275 		case CLOCK:
276 			kb_state.buf[kb_state.len++] = scancode;
277 			if (kb_state.len == 6) {
278 				kb_state.state = KEYBOARD;
279 				/* wake up someone waiting for this.
280 				   But will this ever be used, as Linux keeps its own time.
281 				   Perhaps for synchronization purposes? */
282 				/* wake_up_interruptible(&clock_wait); */
283 			}
284 			break;
285 
286 		case RESYNC:
287 			if (kb_state.len <= 0 || IS_SYNC_CODE(scancode)) {
288 				kb_state.state = KEYBOARD;
289 				goto interpret_scancode;
290 			}
291 			kb_state.len--;
292 			break;
293 		}
294 	}
295 
296 #if 0
297 	if (acia_stat & ACIA_CTS)
298 		/* cannot happen */;
299 #endif
300 
301 	if (acia_stat & (ACIA_FE | ACIA_PE)) {
302 		pr_err("Error in keyboard communication\n");
303 	}
304 
305 	/* handle_scancode() can take a lot of time, so check again if
306 	 * some character arrived
307 	 */
308 	goto repeat;
309 }
310 
311 /*
312  * I write to the keyboard without using interrupts, I poll instead.
313  * This takes for the maximum length string allowed (7) at 7812.5 baud
314  * 8 data 1 start 1 stop bit: 9.0 ms
315  * If this takes too long for normal operation, interrupt driven writing
316  * is the solution. (I made a feeble attempt in that direction but I
317  * kept it simple for now.)
318  */
ikbd_write(const char * str,int len)319 void ikbd_write(const char *str, int len)
320 {
321 	u_char acia_stat;
322 
323 	if ((len < 1) || (len > 7))
324 		panic("ikbd: maximum string length exceeded");
325 	while (len) {
326 		acia_stat = acia.key_ctrl;
327 		if (acia_stat & ACIA_TDRE) {
328 			acia.key_data = *str++;
329 			len--;
330 		}
331 	}
332 }
333 
334 /* Reset (without touching the clock) */
ikbd_reset(void)335 void ikbd_reset(void)
336 {
337 	static const char cmd[2] = { 0x80, 0x01 };
338 
339 	ikbd_write(cmd, 2);
340 
341 	/*
342 	 * if all's well code 0xF1 is returned, else the break codes of
343 	 * all keys making contact
344 	 */
345 }
346 
347 /* Set mouse button action */
ikbd_mouse_button_action(int mode)348 void ikbd_mouse_button_action(int mode)
349 {
350 	char cmd[2] = { 0x07, mode };
351 
352 	ikbd_write(cmd, 2);
353 }
354 
355 /* Set relative mouse position reporting */
ikbd_mouse_rel_pos(void)356 void ikbd_mouse_rel_pos(void)
357 {
358 	static const char cmd[1] = { 0x08 };
359 
360 	ikbd_write(cmd, 1);
361 }
362 EXPORT_SYMBOL(ikbd_mouse_rel_pos);
363 
364 /* Set absolute mouse position reporting */
ikbd_mouse_abs_pos(int xmax,int ymax)365 void ikbd_mouse_abs_pos(int xmax, int ymax)
366 {
367 	char cmd[5] = { 0x09, xmax>>8, xmax&0xFF, ymax>>8, ymax&0xFF };
368 
369 	ikbd_write(cmd, 5);
370 }
371 
372 /* Set mouse keycode mode */
ikbd_mouse_kbd_mode(int dx,int dy)373 void ikbd_mouse_kbd_mode(int dx, int dy)
374 {
375 	char cmd[3] = { 0x0A, dx, dy };
376 
377 	ikbd_write(cmd, 3);
378 }
379 
380 /* Set mouse threshold */
ikbd_mouse_thresh(int x,int y)381 void ikbd_mouse_thresh(int x, int y)
382 {
383 	char cmd[3] = { 0x0B, x, y };
384 
385 	ikbd_write(cmd, 3);
386 }
387 EXPORT_SYMBOL(ikbd_mouse_thresh);
388 
389 /* Set mouse scale */
ikbd_mouse_scale(int x,int y)390 void ikbd_mouse_scale(int x, int y)
391 {
392 	char cmd[3] = { 0x0C, x, y };
393 
394 	ikbd_write(cmd, 3);
395 }
396 
397 /* Interrogate mouse position */
ikbd_mouse_pos_get(int * x,int * y)398 void ikbd_mouse_pos_get(int *x, int *y)
399 {
400 	static const char cmd[1] = { 0x0D };
401 
402 	ikbd_write(cmd, 1);
403 
404 	/* wait for returning bytes */
405 }
406 
407 /* Load mouse position */
ikbd_mouse_pos_set(int x,int y)408 void ikbd_mouse_pos_set(int x, int y)
409 {
410 	char cmd[6] = { 0x0E, 0x00, x>>8, x&0xFF, y>>8, y&0xFF };
411 
412 	ikbd_write(cmd, 6);
413 }
414 
415 /* Set Y=0 at bottom */
ikbd_mouse_y0_bot(void)416 void ikbd_mouse_y0_bot(void)
417 {
418 	static const char cmd[1] = { 0x0F };
419 
420 	ikbd_write(cmd, 1);
421 }
422 
423 /* Set Y=0 at top */
ikbd_mouse_y0_top(void)424 void ikbd_mouse_y0_top(void)
425 {
426 	static const char cmd[1] = { 0x10 };
427 
428 	ikbd_write(cmd, 1);
429 }
430 EXPORT_SYMBOL(ikbd_mouse_y0_top);
431 
432 /* Disable mouse */
ikbd_mouse_disable(void)433 void ikbd_mouse_disable(void)
434 {
435 	static const char cmd[1] = { 0x12 };
436 
437 	ikbd_write(cmd, 1);
438 }
439 EXPORT_SYMBOL(ikbd_mouse_disable);
440 
441 /* Set joystick event reporting */
ikbd_joystick_event_on(void)442 void ikbd_joystick_event_on(void)
443 {
444 	static const char cmd[1] = { 0x14 };
445 
446 	ikbd_write(cmd, 1);
447 }
448 
449 /* Set joystick interrogation mode */
ikbd_joystick_event_off(void)450 void ikbd_joystick_event_off(void)
451 {
452 	static const char cmd[1] = { 0x15 };
453 
454 	ikbd_write(cmd, 1);
455 }
456 
457 /* Joystick interrogation */
ikbd_joystick_get_state(void)458 void ikbd_joystick_get_state(void)
459 {
460 	static const char cmd[1] = { 0x16 };
461 
462 	ikbd_write(cmd, 1);
463 }
464 
465 #if 0
466 /* This disables all other ikbd activities !!!! */
467 /* Set joystick monitoring */
468 void ikbd_joystick_monitor(int rate)
469 {
470 	static const char cmd[2] = { 0x17, rate };
471 
472 	ikbd_write(cmd, 2);
473 
474 	kb_state.state = JOYSTICK_MONITOR;
475 }
476 #endif
477 
478 /* some joystick routines not in yet (0x18-0x19) */
479 
480 /* Disable joysticks */
ikbd_joystick_disable(void)481 void ikbd_joystick_disable(void)
482 {
483 	static const char cmd[1] = { 0x1A };
484 
485 	ikbd_write(cmd, 1);
486 }
487 
488 /*
489  * The original code sometimes left the interrupt line of
490  * the ACIAs low forever. I hope, it is fixed now.
491  *
492  * Martin Rogge, 20 Aug 1995
493  */
494 
495 static int atari_keyb_done = 0;
496 
atari_keyb_init(void)497 int atari_keyb_init(void)
498 {
499 	int error;
500 
501 	if (atari_keyb_done)
502 		return 0;
503 
504 	kb_state.state = KEYBOARD;
505 	kb_state.len = 0;
506 
507 	error = request_irq(IRQ_MFP_ACIA, atari_keyboard_interrupt, 0,
508 			    "keyboard,mouse,MIDI", atari_keyboard_interrupt);
509 	if (error)
510 		return error;
511 
512 	atari_turnoff_irq(IRQ_MFP_ACIA);
513 	do {
514 		/* reset IKBD ACIA */
515 		acia.key_ctrl = ACIA_RESET |
516 				((atari_switches & ATARI_SWITCH_IKBD) ?
517 				 ACIA_RHTID : 0);
518 		(void)acia.key_ctrl;
519 		(void)acia.key_data;
520 
521 		/* reset MIDI ACIA */
522 		acia.mid_ctrl = ACIA_RESET |
523 				((atari_switches & ATARI_SWITCH_MIDI) ?
524 				 ACIA_RHTID : 0);
525 		(void)acia.mid_ctrl;
526 		(void)acia.mid_data;
527 
528 		/* divide 500kHz by 64 gives 7812.5 baud */
529 		/* 8 data no parity 1 start 1 stop bit */
530 		/* receive interrupt enabled */
531 		/* RTS low (except if switch selected), transmit interrupt disabled */
532 		acia.key_ctrl = (ACIA_DIV64|ACIA_D8N1S|ACIA_RIE) |
533 				((atari_switches & ATARI_SWITCH_IKBD) ?
534 				 ACIA_RHTID : ACIA_RLTID);
535 
536 		acia.mid_ctrl = ACIA_DIV16 | ACIA_D8N1S |
537 				((atari_switches & ATARI_SWITCH_MIDI) ?
538 				 ACIA_RHTID : 0);
539 
540 	/* make sure the interrupt line is up */
541 	} while ((st_mfp.par_dt_reg & 0x10) == 0);
542 
543 	/* enable ACIA Interrupts */
544 	st_mfp.active_edge &= ~0x10;
545 	atari_turnon_irq(IRQ_MFP_ACIA);
546 
547 	ikbd_self_test = 1;
548 	ikbd_reset();
549 	/* wait for a period of inactivity (here: 0.25s), then assume the IKBD's
550 	 * self-test is finished */
551 	self_test_last_rcv = jiffies;
552 	while (time_before(jiffies, self_test_last_rcv + HZ/4))
553 		barrier();
554 	/* if not incremented: no 0xf1 received */
555 	if (ikbd_self_test == 1)
556 		pr_err("Keyboard self test failed!\n");
557 	ikbd_self_test = 0;
558 
559 	ikbd_mouse_disable();
560 	ikbd_joystick_disable();
561 
562 #ifdef FIXED_ATARI_JOYSTICK
563 	atari_joystick_init();
564 #endif
565 
566 	// flag init done
567 	atari_keyb_done = 1;
568 	return 0;
569 }
570 EXPORT_SYMBOL_GPL(atari_keyb_init);
571