arch/m68k/atari/atakeyb.c - kernel/msm-4.19 - Gitiles

 /*
  * Atari Keyboard driver for 680x0 Linux
  *
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file COPYING in the main directory of this archive
  * for more details.
  */

 /*
  * Atari support by Robert de Vries
  * enhanced by Bjoern Brauel and Roman Hodek
  *
  * 2.6 and input cleanup (removed autorepeat stuff) for 2.6.21
  * 06/07 Michael Schmitz
  */

 #include <linux/module.h>
 #include <linux/sched.h>
 #include <linux/kernel.h>
 #include <linux/interrupt.h>
 #include <linux/errno.h>
 #include <linux/keyboard.h>
 #include <linux/delay.h>
 #include <linux/timer.h>
 #include <linux/kd.h>
 #include <linux/random.h>
 #include <linux/init.h>
 #include <linux/kbd_kern.h>

 #include <asm/atariints.h>
 #include <asm/atarihw.h>
 #include <asm/atarikb.h>
 #include <asm/atari_joystick.h>
 #include <asm/irq.h>

 extern unsigned int keymap_count;

 /* Hook for MIDI serial driver */
 void (*atari_MIDI_interrupt_hook) (void);
 /* Hook for mouse driver */
 void (*atari_mouse_interrupt_hook) (char *);
 /* Hook for keyboard inputdev  driver */
 void (*atari_input_keyboard_interrupt_hook) (unsigned char, char);
 /* Hook for mouse inputdev  driver */
 void (*atari_input_mouse_interrupt_hook) (char *);
 EXPORT_SYMBOL(atari_mouse_interrupt_hook);
 EXPORT_SYMBOL(atari_input_keyboard_interrupt_hook);
 EXPORT_SYMBOL(atari_input_mouse_interrupt_hook);

 /* variables for IKBD self test: */

 /* state: 0: off; >0: in progress; >1: 0xf1 received */
 static volatile int ikbd_self_test;
 /* timestamp when last received a char */
 static volatile unsigned long self_test_last_rcv;
 /* bitmap of keys reported as broken */
 static unsigned long broken_keys[128/(sizeof(unsigned long)*8)] = { 0, };

 #define BREAK_MASK	(0x80)

 /*
  * ++roman: The following changes were applied manually:
  *
  *  - The Alt (= Meta) key works in combination with Shift and
  *    Control, e.g. Alt+Shift+a sends Meta-A (0xc1), Alt+Control+A sends
  *    Meta-Ctrl-A (0x81) ...
  *
  *  - The parentheses on the keypad send '(' and ')' with all
  *    modifiers (as would do e.g. keypad '+'), but they cannot be used as
  *    application keys (i.e. sending Esc O c).
  *
  *  - HELP and UNDO are mapped to be F21 and F24, resp, that send the
  *    codes "\E[M" and "\E[P". (This is better than the old mapping to
  *    F11 and F12, because these codes are on Shift+F1/2 anyway.) This
  *    way, applications that allow their own keyboard mappings
  *    (e.g. tcsh, X Windows) can be configured to use them in the way
  *    the label suggests (providing help or undoing).
  *
  *  - Console switching is done with Alt+Fx (consoles 1..10) and
  *    Shift+Alt+Fx (consoles 11..20).
  *
  *  - The misc. special function implemented in the kernel are mapped
  *    to the following key combinations:
  *
  *      ClrHome          -> Home/Find
  *      Shift + ClrHome  -> End/Select
  *      Shift + Up       -> Page Up
  *      Shift + Down     -> Page Down
  *      Alt + Help       -> show system status
  *      Shift + Help     -> show memory info
  *      Ctrl + Help      -> show registers
  *      Ctrl + Alt + Del -> Reboot
  *      Alt + Undo       -> switch to last console
  *      Shift + Undo     -> send interrupt
  *      Alt + Insert     -> stop/start output (same as ^S/^Q)
  *      Alt + Up         -> Scroll back console (if implemented)
  *      Alt + Down       -> Scroll forward console (if implemented)
  *      Alt + CapsLock   -> NumLock
  *
  * ++Andreas:
  *
  *  - Help mapped to K_HELP
  *  - Undo mapped to K_UNDO (= K_F246)
  *  - Keypad Left/Right Parenthesis mapped to new K_PPAREN[LR]
  */

 typedef enum kb_state_t {
 	KEYBOARD, AMOUSE, RMOUSE, JOYSTICK, CLOCK, RESYNC
 } KB_STATE_T;

 #define	IS_SYNC_CODE(sc)	((sc) >= 0x04 && (sc) <= 0xfb)

 typedef struct keyboard_state {
 	unsigned char buf[6];
 	int len;
 	KB_STATE_T state;
 } KEYBOARD_STATE;

 KEYBOARD_STATE kb_state;

 /* ++roman: If a keyboard overrun happened, we can't tell in general how much
  * bytes have been lost and in which state of the packet structure we are now.
  * This usually causes keyboards bytes to be interpreted as mouse movements
  * and vice versa, which is very annoying. It seems better to throw away some
  * bytes (that are usually mouse bytes) than to misinterpret them. Therefor I
  * introduced the RESYNC state for IKBD data. In this state, the bytes up to
  * one that really looks like a key event (0x04..0xf2) or the start of a mouse
  * packet (0xf8..0xfb) are thrown away, but at most 2 bytes. This at least
  * speeds up the resynchronization of the event structure, even if maybe a
  * mouse movement is lost. However, nothing is perfect. For bytes 0x01..0x03,
  * it's really hard to decide whether they're mouse or keyboard bytes. Since
  * overruns usually occur when moving the Atari mouse rapidly, they're seen as
  * mouse bytes here. If this is wrong, only a make code of the keyboard gets
  * lost, which isn't too bad. Loosing a break code would be disastrous,
  * because then the keyboard repeat strikes...
  */

 static irqreturn_t atari_keyboard_interrupt(int irq, void *dummy)
 {
 	u_char acia_stat;
 	int scancode;
 	int break_flag;

 repeat:
 	if (acia.mid_ctrl & ACIA_IRQ)
 		if (atari_MIDI_interrupt_hook)
 			atari_MIDI_interrupt_hook();
 	acia_stat = acia.key_ctrl;
 	/* check out if the interrupt came from this ACIA */
 	if (!((acia_stat | acia.mid_ctrl) & ACIA_IRQ))
 		return IRQ_HANDLED;

 	if (acia_stat & ACIA_OVRN) {
 		/* a very fast typist or a slow system, give a warning */
 		/* ...happens often if interrupts were disabled for too long */
 		printk(KERN_DEBUG "Keyboard overrun\n");
 		scancode = acia.key_data;
 		if (ikbd_self_test)
 			/* During self test, don't do resyncing, just process the code */
 			goto interpret_scancode;
 		else if (IS_SYNC_CODE(scancode)) {
 			/* This code seem already to be the start of a new packet or a
 			 * single scancode */
 			kb_state.state = KEYBOARD;
 			goto interpret_scancode;
 		} else {
 			/* Go to RESYNC state and skip this byte */
 			kb_state.state = RESYNC;
 			kb_state.len = 1;	/* skip max. 1 another byte */
 			goto repeat;
 		}
 	}

 	if (acia_stat & ACIA_RDRF) {
 		/* received a character */
 		scancode = acia.key_data;	/* get it or reset the ACIA, I'll get it! */
 		tasklet_schedule(&keyboard_tasklet);
 	interpret_scancode:
 		switch (kb_state.state) {
 		case KEYBOARD:
 			switch (scancode) {
 			case 0xF7:
 				kb_state.state = AMOUSE;
 				kb_state.len = 0;
 				break;

 			case 0xF8:
 			case 0xF9:
 			case 0xFA:
 			case 0xFB:
 				kb_state.state = RMOUSE;
 				kb_state.len = 1;
 				kb_state.buf[0] = scancode;
 				break;

 			case 0xFC:
 				kb_state.state = CLOCK;
 				kb_state.len = 0;
 				break;

 			case 0xFE:
 			case 0xFF:
 				kb_state.state = JOYSTICK;
 				kb_state.len = 1;
 				kb_state.buf[0] = scancode;
 				break;

 			case 0xF1:
 				/* during self-test, note that 0xf1 received */
 				if (ikbd_self_test) {
 					++ikbd_self_test;
 					self_test_last_rcv = jiffies;
 					break;
 				}
 				/* FALL THROUGH */

 			default:
 				break_flag = scancode & BREAK_MASK;
 				scancode &= ~BREAK_MASK;
 				if (ikbd_self_test) {
 					/* Scancodes sent during the self-test stand for broken
 					 * keys (keys being down). The code *should* be a break
 					 * code, but nevertheless some AT keyboard interfaces send
 					 * make codes instead. Therefore, simply ignore
 					 * break_flag...
 					 */
 					int keyval, keytyp;

 					set_bit(scancode, broken_keys);
 					self_test_last_rcv = jiffies;
 					/* new Linux scancodes; approx. */
 					keyval = scancode;
 					keytyp = KTYP(keyval) - 0xf0;
 					keyval = KVAL(keyval);

 					printk(KERN_WARNING "Key with scancode %d ", scancode);
 					if (keytyp == KT_LATIN || keytyp == KT_LETTER) {
 						if (keyval < ' ')
 							printk("('^%c') ", keyval + '@');
 						else
 							printk("('%c') ", keyval);
 					}
 					printk("is broken -- will be ignored.\n");
 					break;
 				} else if (test_bit(scancode, broken_keys))
 					break;

 				if (atari_input_keyboard_interrupt_hook)
 					atari_input_keyboard_interrupt_hook((unsigned char)scancode, !break_flag);
 				break;
 			}
 			break;

 		case AMOUSE:
 			kb_state.buf[kb_state.len++] = scancode;
 			if (kb_state.len == 5) {
 				kb_state.state = KEYBOARD;
 				/* not yet used */
 				/* wake up someone waiting for this */
 			}
 			break;

 		case RMOUSE:
 			kb_state.buf[kb_state.len++] = scancode;
 			if (kb_state.len == 3) {
 				kb_state.state = KEYBOARD;
 				if (atari_mouse_interrupt_hook)
 					atari_mouse_interrupt_hook(kb_state.buf);
 			}
 			break;

 		case JOYSTICK:
 			kb_state.buf[1] = scancode;
 			kb_state.state = KEYBOARD;
 #ifdef FIXED_ATARI_JOYSTICK
 			atari_joystick_interrupt(kb_state.buf);
 #endif
 			break;

 		case CLOCK:
 			kb_state.buf[kb_state.len++] = scancode;
 			if (kb_state.len == 6) {
 				kb_state.state = KEYBOARD;
 				/* wake up someone waiting for this.
 				   But will this ever be used, as Linux keeps its own time.
 				   Perhaps for synchronization purposes? */
 				/* wake_up_interruptible(&clock_wait); */
 			}
 			break;

 		case RESYNC:
 			if (kb_state.len <= 0 || IS_SYNC_CODE(scancode)) {
 				kb_state.state = KEYBOARD;
 				goto interpret_scancode;
 			}
 			kb_state.len--;
 			break;
 		}
 	}

 #if 0
 	if (acia_stat & ACIA_CTS)
 		/* cannot happen */;
 #endif

 	if (acia_stat & (ACIA_FE | ACIA_PE)) {
 		printk("Error in keyboard communication\n");
 	}

 	/* handle_scancode() can take a lot of time, so check again if
 	 * some character arrived
 	 */
 	goto repeat;
 }

 /*
  * I write to the keyboard without using interrupts, I poll instead.
  * This takes for the maximum length string allowed (7) at 7812.5 baud
  * 8 data 1 start 1 stop bit: 9.0 ms
  * If this takes too long for normal operation, interrupt driven writing
  * is the solution. (I made a feeble attempt in that direction but I
  * kept it simple for now.)
  */
 void ikbd_write(const char *str, int len)
 {
 	u_char acia_stat;

 	if ((len < 1) || (len > 7))
 		panic("ikbd: maximum string length exceeded");
 	while (len) {
 		acia_stat = acia.key_ctrl;
 		if (acia_stat & ACIA_TDRE) {
 			acia.key_data = *str++;
 			len--;
 		}
 	}
 }

 /* Reset (without touching the clock) */
 void ikbd_reset(void)
 {
 	static const char cmd[2] = { 0x80, 0x01 };

 	ikbd_write(cmd, 2);

 	/*
 	 * if all's well code 0xF1 is returned, else the break codes of
 	 * all keys making contact
 	 */
 }

 /* Set mouse button action */
 void ikbd_mouse_button_action(int mode)
 {
 	char cmd[2] = { 0x07, mode };

 	ikbd_write(cmd, 2);
 }

 /* Set relative mouse position reporting */
 void ikbd_mouse_rel_pos(void)
 {
 	static const char cmd[1] = { 0x08 };

 	ikbd_write(cmd, 1);
 }
 EXPORT_SYMBOL(ikbd_mouse_rel_pos);

 /* Set absolute mouse position reporting */
 void ikbd_mouse_abs_pos(int xmax, int ymax)
 {
 	char cmd[5] = { 0x09, xmax>>8, xmax&0xFF, ymax>>8, ymax&0xFF };

 	ikbd_write(cmd, 5);
 }

 /* Set mouse keycode mode */
 void ikbd_mouse_kbd_mode(int dx, int dy)
 {
 	char cmd[3] = { 0x0A, dx, dy };

 	ikbd_write(cmd, 3);
 }

 /* Set mouse threshold */
 void ikbd_mouse_thresh(int x, int y)
 {
 	char cmd[3] = { 0x0B, x, y };

 	ikbd_write(cmd, 3);
 }
 EXPORT_SYMBOL(ikbd_mouse_thresh);

 /* Set mouse scale */
 void ikbd_mouse_scale(int x, int y)
 {
 	char cmd[3] = { 0x0C, x, y };

 	ikbd_write(cmd, 3);
 }

 /* Interrogate mouse position */
 void ikbd_mouse_pos_get(int *x, int *y)
 {
 	static const char cmd[1] = { 0x0D };

 	ikbd_write(cmd, 1);

 	/* wait for returning bytes */
 }

 /* Load mouse position */
 void ikbd_mouse_pos_set(int x, int y)
 {
 	char cmd[6] = { 0x0E, 0x00, x>>8, x&0xFF, y>>8, y&0xFF };

 	ikbd_write(cmd, 6);
 }

 /* Set Y=0 at bottom */
 void ikbd_mouse_y0_bot(void)
 {
 	static const char cmd[1] = { 0x0F };

 	ikbd_write(cmd, 1);
 }

 /* Set Y=0 at top */
 void ikbd_mouse_y0_top(void)
 {
 	static const char cmd[1] = { 0x10 };

 	ikbd_write(cmd, 1);
 }
 EXPORT_SYMBOL(ikbd_mouse_y0_top);

 /* Resume */
 void ikbd_resume(void)
 {
 	static const char cmd[1] = { 0x11 };

 	ikbd_write(cmd, 1);
 }

 /* Disable mouse */
 void ikbd_mouse_disable(void)
 {
 	static const char cmd[1] = { 0x12 };

 	ikbd_write(cmd, 1);
 }
 EXPORT_SYMBOL(ikbd_mouse_disable);

 /* Pause output */
 void ikbd_pause(void)
 {
 	static const char cmd[1] = { 0x13 };

 	ikbd_write(cmd, 1);
 }

 /* Set joystick event reporting */
 void ikbd_joystick_event_on(void)
 {
 	static const char cmd[1] = { 0x14 };

 	ikbd_write(cmd, 1);
 }

 /* Set joystick interrogation mode */
 void ikbd_joystick_event_off(void)
 {
 	static const char cmd[1] = { 0x15 };

 	ikbd_write(cmd, 1);
 }

 /* Joystick interrogation */
 void ikbd_joystick_get_state(void)
 {
 	static const char cmd[1] = { 0x16 };

 	ikbd_write(cmd, 1);
 }

 #if 0
 /* This disables all other ikbd activities !!!! */
 /* Set joystick monitoring */
 void ikbd_joystick_monitor(int rate)
 {
 	static const char cmd[2] = { 0x17, rate };

 	ikbd_write(cmd, 2);

 	kb_state.state = JOYSTICK_MONITOR;
 }
 #endif

 /* some joystick routines not in yet (0x18-0x19) */

 /* Disable joysticks */
 void ikbd_joystick_disable(void)
 {
 	static const char cmd[1] = { 0x1A };

 	ikbd_write(cmd, 1);
 }

 /* Time-of-day clock set */
 void ikbd_clock_set(int year, int month, int day, int hour, int minute, int second)
 {
 	char cmd[7] = { 0x1B, year, month, day, hour, minute, second };

 	ikbd_write(cmd, 7);
 }

 /* Interrogate time-of-day clock */
 void ikbd_clock_get(int *year, int *month, int *day, int *hour, int *minute, int second)
 {
 	static const char cmd[1] = { 0x1C };

 	ikbd_write(cmd, 1);
 }

 /* Memory load */
 void ikbd_mem_write(int address, int size, char *data)
 {
 	panic("Attempt to write data into keyboard memory");
 }

 /* Memory read */
 void ikbd_mem_read(int address, char data[6])
 {
 	char cmd[3] = { 0x21, address>>8, address&0xFF };

 	ikbd_write(cmd, 3);

 	/* receive data and put it in data */
 }

 /* Controller execute */
 void ikbd_exec(int address)
 {
 	char cmd[3] = { 0x22, address>>8, address&0xFF };

 	ikbd_write(cmd, 3);
 }

 /* Status inquiries (0x87-0x9A) not yet implemented */

 /* Set the state of the caps lock led. */
 void atari_kbd_leds(unsigned int leds)
 {
 	char cmd[6] = {32, 0, 4, 1, 254 + ((leds & 4) != 0), 0};

 	ikbd_write(cmd, 6);
 }

 /*
  * The original code sometimes left the interrupt line of
  * the ACIAs low forever. I hope, it is fixed now.
  *
  * Martin Rogge, 20 Aug 1995
  */

 static int atari_keyb_done = 0;

 int __init atari_keyb_init(void)
 {
 	if (atari_keyb_done)
 		return 0;

 	kb_state.state = KEYBOARD;
 	kb_state.len = 0;

 	request_irq(IRQ_MFP_ACIA, atari_keyboard_interrupt, IRQ_TYPE_SLOW,
 		    "keyboard/mouse/MIDI", atari_keyboard_interrupt);

 	atari_turnoff_irq(IRQ_MFP_ACIA);
 	do {
 		/* reset IKBD ACIA */
 		acia.key_ctrl = ACIA_RESET |
 				(atari_switches & ATARI_SWITCH_IKBD) ? ACIA_RHTID : 0;
 		(void)acia.key_ctrl;
 		(void)acia.key_data;

 		/* reset MIDI ACIA */
 		acia.mid_ctrl = ACIA_RESET |
 				(atari_switches & ATARI_SWITCH_MIDI) ? ACIA_RHTID : 0;
 		(void)acia.mid_ctrl;
 		(void)acia.mid_data;

 		/* divide 500kHz by 64 gives 7812.5 baud */
 		/* 8 data no parity 1 start 1 stop bit */
 		/* receive interrupt enabled */
 		/* RTS low (except if switch selected), transmit interrupt disabled */
 		acia.key_ctrl = (ACIA_DIV64|ACIA_D8N1S|ACIA_RIE) |
 				((atari_switches & ATARI_SWITCH_IKBD) ?
 				 ACIA_RHTID : ACIA_RLTID);

 		acia.mid_ctrl = ACIA_DIV16 | ACIA_D8N1S |
 				(atari_switches & ATARI_SWITCH_MIDI) ? ACIA_RHTID : 0;

 	/* make sure the interrupt line is up */
 	} while ((mfp.par_dt_reg & 0x10) == 0);

 	/* enable ACIA Interrupts */
 	mfp.active_edge &= ~0x10;
 	atari_turnon_irq(IRQ_MFP_ACIA);

 	ikbd_self_test = 1;
 	ikbd_reset();
 	/* wait for a period of inactivity (here: 0.25s), then assume the IKBD's
 	 * self-test is finished */
 	self_test_last_rcv = jiffies;
 	while (time_before(jiffies, self_test_last_rcv + HZ/4))
 		barrier();
 	/* if not incremented: no 0xf1 received */
 	if (ikbd_self_test == 1)
 		printk(KERN_ERR "WARNING: keyboard self test failed!\n");
 	ikbd_self_test = 0;

 	ikbd_mouse_disable();
 	ikbd_joystick_disable();

 #ifdef FIXED_ATARI_JOYSTICK
 	atari_joystick_init();
 #endif

 	// flag init done
 	atari_keyb_done = 1;
 	return 0;
 }

 int atari_kbd_translate(unsigned char keycode, unsigned char *keycodep, char raw_mode)
 {
 #ifdef CONFIG_MAGIC_SYSRQ
 	/* ALT+HELP pressed? */
 	if ((keycode == 98) && ((shift_state & 0xff) == 8))
 		*keycodep = 0xff;
 	else
 #endif
 		*keycodep = keycode;
 	return 1;
 }
	/*
	* Atari Keyboard driver for 680x0 Linux
	*
	* This file is subject to the terms and conditions of the GNU General Public
	* License. See the file COPYING in the main directory of this archive
	* for more details.
	*/

	/*
	* Atari support by Robert de Vries
	* enhanced by Bjoern Brauel and Roman Hodek
	*
	* 2.6 and input cleanup (removed autorepeat stuff) for 2.6.21
	* 06/07 Michael Schmitz
	*/

	#include <linux/module.h>
	#include <linux/sched.h>
	#include <linux/kernel.h>
	#include <linux/interrupt.h>
	#include <linux/errno.h>
	#include <linux/keyboard.h>
	#include <linux/delay.h>
	#include <linux/timer.h>
	#include <linux/kd.h>
	#include <linux/random.h>
	#include <linux/init.h>
	#include <linux/kbd_kern.h>

	#include <asm/atariints.h>
	#include <asm/atarihw.h>
	#include <asm/atarikb.h>
	#include <asm/atari_joystick.h>
	#include <asm/irq.h>

	extern unsigned int keymap_count;

	/* Hook for MIDI serial driver */
	void (*atari_MIDI_interrupt_hook) (void);
	/* Hook for mouse driver */
	void (atari_mouse_interrupt_hook) (char );
	/* Hook for keyboard inputdev driver */
	void (*atari_input_keyboard_interrupt_hook) (unsigned char, char);
	/* Hook for mouse inputdev driver */
	void (atari_input_mouse_interrupt_hook) (char );
	EXPORT_SYMBOL(atari_mouse_interrupt_hook);
	EXPORT_SYMBOL(atari_input_keyboard_interrupt_hook);
	EXPORT_SYMBOL(atari_input_mouse_interrupt_hook);

	/* variables for IKBD self test: */

	/* state: 0: off; >0: in progress; >1: 0xf1 received */
	static volatile int ikbd_self_test;
	/* timestamp when last received a char */
	static volatile unsigned long self_test_last_rcv;
	/* bitmap of keys reported as broken */
	static unsigned long broken_keys[128/(sizeof(unsigned long)*8)] = { 0, };

	#define BREAK_MASK (0x80)

	/*
	* ++roman: The following changes were applied manually:
	*
	* - The Alt (= Meta) key works in combination with Shift and
	* Control, e.g. Alt+Shift+a sends Meta-A (0xc1), Alt+Control+A sends
	* Meta-Ctrl-A (0x81) ...
	*
	* - The parentheses on the keypad send '(' and ')' with all
	* modifiers (as would do e.g. keypad '+'), but they cannot be used as
	* application keys (i.e. sending Esc O c).
	*
	* - HELP and UNDO are mapped to be F21 and F24, resp, that send the
	* codes "\E[M" and "\E[P". (This is better than the old mapping to
	* F11 and F12, because these codes are on Shift+F1/2 anyway.) This
	* way, applications that allow their own keyboard mappings
	* (e.g. tcsh, X Windows) can be configured to use them in the way
	* the label suggests (providing help or undoing).
	*
	* - Console switching is done with Alt+Fx (consoles 1..10) and
	* Shift+Alt+Fx (consoles 11..20).
	*
	* - The misc. special function implemented in the kernel are mapped
	* to the following key combinations:
	*
	* ClrHome -> Home/Find
	* Shift + ClrHome -> End/Select
	* Shift + Up -> Page Up
	* Shift + Down -> Page Down
	* Alt + Help -> show system status
	* Shift + Help -> show memory info
	* Ctrl + Help -> show registers
	* Ctrl + Alt + Del -> Reboot
	* Alt + Undo -> switch to last console
	* Shift + Undo -> send interrupt
	* Alt + Insert -> stop/start output (same as ^S/^Q)
	* Alt + Up -> Scroll back console (if implemented)
	* Alt + Down -> Scroll forward console (if implemented)
	* Alt + CapsLock -> NumLock
	*
	* ++Andreas:
	*
	* - Help mapped to K_HELP
	* - Undo mapped to K_UNDO (= K_F246)
	* - Keypad Left/Right Parenthesis mapped to new K_PPAREN[LR]
	*/

	typedef enum kb_state_t {
	KEYBOARD, AMOUSE, RMOUSE, JOYSTICK, CLOCK, RESYNC
	} KB_STATE_T;

	#define IS_SYNC_CODE(sc) ((sc) >= 0x04 && (sc) <= 0xfb)

	typedef struct keyboard_state {
	unsigned char buf[6];
	int len;
	KB_STATE_T state;
	} KEYBOARD_STATE;

	KEYBOARD_STATE kb_state;

	/* ++roman: If a keyboard overrun happened, we can't tell in general how much
	* bytes have been lost and in which state of the packet structure we are now.
	* This usually causes keyboards bytes to be interpreted as mouse movements
	* and vice versa, which is very annoying. It seems better to throw away some
	* bytes (that are usually mouse bytes) than to misinterpret them. Therefor I
	* introduced the RESYNC state for IKBD data. In this state, the bytes up to
	* one that really looks like a key event (0x04..0xf2) or the start of a mouse
	* packet (0xf8..0xfb) are thrown away, but at most 2 bytes. This at least
	* speeds up the resynchronization of the event structure, even if maybe a
	* mouse movement is lost. However, nothing is perfect. For bytes 0x01..0x03,
	* it's really hard to decide whether they're mouse or keyboard bytes. Since
	* overruns usually occur when moving the Atari mouse rapidly, they're seen as
	* mouse bytes here. If this is wrong, only a make code of the keyboard gets
	* lost, which isn't too bad. Loosing a break code would be disastrous,
	* because then the keyboard repeat strikes...
	*/

	static irqreturn_t atari_keyboard_interrupt(int irq, void *dummy)
	{
	u_char acia_stat;
	int scancode;
	int break_flag;

	repeat:
	if (acia.mid_ctrl & ACIA_IRQ)
	if (atari_MIDI_interrupt_hook)
	atari_MIDI_interrupt_hook();
	acia_stat = acia.key_ctrl;
	/* check out if the interrupt came from this ACIA */
	if (!((acia_stat \| acia.mid_ctrl) & ACIA_IRQ))
	return IRQ_HANDLED;

	if (acia_stat & ACIA_OVRN) {
	/* a very fast typist or a slow system, give a warning */
	/* ...happens often if interrupts were disabled for too long */
	printk(KERN_DEBUG "Keyboard overrun\n");
	scancode = acia.key_data;
	if (ikbd_self_test)
	/* During self test, don't do resyncing, just process the code */
	goto interpret_scancode;
	else if (IS_SYNC_CODE(scancode)) {
	/* This code seem already to be the start of a new packet or a
	* single scancode */
	kb_state.state = KEYBOARD;
	goto interpret_scancode;
	} else {
	/* Go to RESYNC state and skip this byte */
	kb_state.state = RESYNC;
	kb_state.len = 1; /* skip max. 1 another byte */
	goto repeat;
	}
	}

	if (acia_stat & ACIA_RDRF) {
	/* received a character */
	scancode = acia.key_data; /* get it or reset the ACIA, I'll get it! */
	tasklet_schedule(&keyboard_tasklet);
	interpret_scancode:
	switch (kb_state.state) {
	case KEYBOARD:
	switch (scancode) {
	case 0xF7:
	kb_state.state = AMOUSE;
	kb_state.len = 0;
	break;

	case 0xF8:
	case 0xF9:
	case 0xFA:
	case 0xFB:
	kb_state.state = RMOUSE;
	kb_state.len = 1;
	kb_state.buf[0] = scancode;
	break;

	case 0xFC:
	kb_state.state = CLOCK;
	kb_state.len = 0;
	break;

	case 0xFE:
	case 0xFF:
	kb_state.state = JOYSTICK;
	kb_state.len = 1;
	kb_state.buf[0] = scancode;
	break;

	case 0xF1:
	/* during self-test, note that 0xf1 received */
	if (ikbd_self_test) {
	++ikbd_self_test;
	self_test_last_rcv = jiffies;
	break;
	}
	/* FALL THROUGH */

	default:
	break_flag = scancode & BREAK_MASK;
	scancode &= ~BREAK_MASK;
	if (ikbd_self_test) {
	/* Scancodes sent during the self-test stand for broken
	* keys (keys being down). The code should be a break
	* code, but nevertheless some AT keyboard interfaces send
	* make codes instead. Therefore, simply ignore
	* break_flag...
	*/
	int keyval, keytyp;

	set_bit(scancode, broken_keys);
	self_test_last_rcv = jiffies;
	/* new Linux scancodes; approx. */
	keyval = scancode;
	keytyp = KTYP(keyval) - 0xf0;
	keyval = KVAL(keyval);

	printk(KERN_WARNING "Key with scancode %d ", scancode);
	if (keytyp == KT_LATIN \|\| keytyp == KT_LETTER) {
	if (keyval < ' ')
	printk("('^%c') ", keyval + '@');
	else
	printk("('%c') ", keyval);
	}
	printk("is broken -- will be ignored.\n");
	break;
	} else if (test_bit(scancode, broken_keys))
	break;

	if (atari_input_keyboard_interrupt_hook)
	atari_input_keyboard_interrupt_hook((unsigned char)scancode, !break_flag);
	break;
	}
	break;

	case AMOUSE:
	kb_state.buf[kb_state.len++] = scancode;
	if (kb_state.len == 5) {
	kb_state.state = KEYBOARD;
	/* not yet used */
	/* wake up someone waiting for this */
	}
	break;

	case RMOUSE:
	kb_state.buf[kb_state.len++] = scancode;
	if (kb_state.len == 3) {
	kb_state.state = KEYBOARD;
	if (atari_mouse_interrupt_hook)
	atari_mouse_interrupt_hook(kb_state.buf);
	}
	break;

	case JOYSTICK:
	kb_state.buf[1] = scancode;
	kb_state.state = KEYBOARD;
	#ifdef FIXED_ATARI_JOYSTICK
	atari_joystick_interrupt(kb_state.buf);
	#endif
	break;

	case CLOCK:
	kb_state.buf[kb_state.len++] = scancode;
	if (kb_state.len == 6) {
	kb_state.state = KEYBOARD;
	/* wake up someone waiting for this.
	But will this ever be used, as Linux keeps its own time.
	Perhaps for synchronization purposes? */
	/* wake_up_interruptible(&clock_wait); */
	}
	break;

	case RESYNC:
	if (kb_state.len <= 0 \|\| IS_SYNC_CODE(scancode)) {
	kb_state.state = KEYBOARD;
	goto interpret_scancode;
	}
	kb_state.len--;
	break;
	}
	}

	#if 0
	if (acia_stat & ACIA_CTS)
	/* cannot happen */;
	#endif

	if (acia_stat & (ACIA_FE \| ACIA_PE)) {
	printk("Error in keyboard communication\n");
	}

	/* handle_scancode() can take a lot of time, so check again if
	* some character arrived
	*/
	goto repeat;
	}

	/*
	* I write to the keyboard without using interrupts, I poll instead.
	* This takes for the maximum length string allowed (7) at 7812.5 baud
	* 8 data 1 start 1 stop bit: 9.0 ms
	* If this takes too long for normal operation, interrupt driven writing
	* is the solution. (I made a feeble attempt in that direction but I
	* kept it simple for now.)
	*/
	void ikbd_write(const char *str, int len)
	{
	u_char acia_stat;

	if ((len < 1) \|\| (len > 7))
	panic("ikbd: maximum string length exceeded");
	while (len) {
	acia_stat = acia.key_ctrl;
	if (acia_stat & ACIA_TDRE) {
	acia.key_data = *str++;
	len--;
	}
	}
	}

	/* Reset (without touching the clock) */
	void ikbd_reset(void)
	{
	static const char cmd[2] = { 0x80, 0x01 };

	ikbd_write(cmd, 2);

	/*
	* if all's well code 0xF1 is returned, else the break codes of
	* all keys making contact
	*/
	}

	/* Set mouse button action */
	void ikbd_mouse_button_action(int mode)
	{
	char cmd[2] = { 0x07, mode };

	ikbd_write(cmd, 2);
	}

	/* Set relative mouse position reporting */
	void ikbd_mouse_rel_pos(void)
	{
	static const char cmd[1] = { 0x08 };

	ikbd_write(cmd, 1);
	}
	EXPORT_SYMBOL(ikbd_mouse_rel_pos);

	/* Set absolute mouse position reporting */
	void ikbd_mouse_abs_pos(int xmax, int ymax)
	{
	char cmd[5] = { 0x09, xmax>>8, xmax&0xFF, ymax>>8, ymax&0xFF };

	ikbd_write(cmd, 5);
	}

	/* Set mouse keycode mode */
	void ikbd_mouse_kbd_mode(int dx, int dy)
	{
	char cmd[3] = { 0x0A, dx, dy };

	ikbd_write(cmd, 3);
	}

	/* Set mouse threshold */
	void ikbd_mouse_thresh(int x, int y)
	{
	char cmd[3] = { 0x0B, x, y };

	ikbd_write(cmd, 3);
	}
	EXPORT_SYMBOL(ikbd_mouse_thresh);

	/* Set mouse scale */
	void ikbd_mouse_scale(int x, int y)
	{
	char cmd[3] = { 0x0C, x, y };

	ikbd_write(cmd, 3);
	}

	/* Interrogate mouse position */
	void ikbd_mouse_pos_get(int x, int y)
	{
	static const char cmd[1] = { 0x0D };

	ikbd_write(cmd, 1);

	/* wait for returning bytes */
	}

	/* Load mouse position */
	void ikbd_mouse_pos_set(int x, int y)
	{
	char cmd[6] = { 0x0E, 0x00, x>>8, x&0xFF, y>>8, y&0xFF };

	ikbd_write(cmd, 6);
	}

	/* Set Y=0 at bottom */
	void ikbd_mouse_y0_bot(void)
	{
	static const char cmd[1] = { 0x0F };

	ikbd_write(cmd, 1);
	}

	/* Set Y=0 at top */
	void ikbd_mouse_y0_top(void)
	{
	static const char cmd[1] = { 0x10 };

	ikbd_write(cmd, 1);
	}
	EXPORT_SYMBOL(ikbd_mouse_y0_top);

	/* Resume */
	void ikbd_resume(void)
	{
	static const char cmd[1] = { 0x11 };

	ikbd_write(cmd, 1);
	}

	/* Disable mouse */
	void ikbd_mouse_disable(void)
	{
	static const char cmd[1] = { 0x12 };

	ikbd_write(cmd, 1);
	}
	EXPORT_SYMBOL(ikbd_mouse_disable);

	/* Pause output */
	void ikbd_pause(void)
	{
	static const char cmd[1] = { 0x13 };

	ikbd_write(cmd, 1);
	}

	/* Set joystick event reporting */
	void ikbd_joystick_event_on(void)
	{
	static const char cmd[1] = { 0x14 };

	ikbd_write(cmd, 1);
	}

	/* Set joystick interrogation mode */
	void ikbd_joystick_event_off(void)
	{
	static const char cmd[1] = { 0x15 };

	ikbd_write(cmd, 1);
	}

	/* Joystick interrogation */
	void ikbd_joystick_get_state(void)
	{
	static const char cmd[1] = { 0x16 };

	ikbd_write(cmd, 1);
	}

	#if 0
	/* This disables all other ikbd activities !!!! */
	/* Set joystick monitoring */
	void ikbd_joystick_monitor(int rate)
	{
	static const char cmd[2] = { 0x17, rate };

	ikbd_write(cmd, 2);

	kb_state.state = JOYSTICK_MONITOR;
	}
	#endif

	/* some joystick routines not in yet (0x18-0x19) */

	/* Disable joysticks */
	void ikbd_joystick_disable(void)
	{
	static const char cmd[1] = { 0x1A };

	ikbd_write(cmd, 1);
	}

	/* Time-of-day clock set */
	void ikbd_clock_set(int year, int month, int day, int hour, int minute, int second)
	{
	char cmd[7] = { 0x1B, year, month, day, hour, minute, second };

	ikbd_write(cmd, 7);
	}

	/* Interrogate time-of-day clock */
	void ikbd_clock_get(int year, int month, int day, int hour, int *minute, int second)
	{
	static const char cmd[1] = { 0x1C };

	ikbd_write(cmd, 1);
	}

	/* Memory load */
	void ikbd_mem_write(int address, int size, char *data)
	{
	panic("Attempt to write data into keyboard memory");
	}

	/* Memory read */
	void ikbd_mem_read(int address, char data[6])
	{
	char cmd[3] = { 0x21, address>>8, address&0xFF };

	ikbd_write(cmd, 3);

	/* receive data and put it in data */
	}

	/* Controller execute */
	void ikbd_exec(int address)
	{
	char cmd[3] = { 0x22, address>>8, address&0xFF };

	ikbd_write(cmd, 3);
	}

	/* Status inquiries (0x87-0x9A) not yet implemented */

	/* Set the state of the caps lock led. */
	void atari_kbd_leds(unsigned int leds)
	{
	char cmd[6] = {32, 0, 4, 1, 254 + ((leds & 4) != 0), 0};

	ikbd_write(cmd, 6);
	}

	/*
	* The original code sometimes left the interrupt line of
	* the ACIAs low forever. I hope, it is fixed now.
	*
	* Martin Rogge, 20 Aug 1995
	*/

	static int atari_keyb_done = 0;

	int __init atari_keyb_init(void)
	{
	if (atari_keyb_done)
	return 0;

	kb_state.state = KEYBOARD;
	kb_state.len = 0;

	request_irq(IRQ_MFP_ACIA, atari_keyboard_interrupt, IRQ_TYPE_SLOW,
	"keyboard/mouse/MIDI", atari_keyboard_interrupt);

	atari_turnoff_irq(IRQ_MFP_ACIA);
	do {
	/* reset IKBD ACIA */
	acia.key_ctrl = ACIA_RESET \|
	(atari_switches & ATARI_SWITCH_IKBD) ? ACIA_RHTID : 0;
	(void)acia.key_ctrl;
	(void)acia.key_data;

	/* reset MIDI ACIA */
	acia.mid_ctrl = ACIA_RESET \|
	(atari_switches & ATARI_SWITCH_MIDI) ? ACIA_RHTID : 0;
	(void)acia.mid_ctrl;
	(void)acia.mid_data;

	/* divide 500kHz by 64 gives 7812.5 baud */
	/* 8 data no parity 1 start 1 stop bit */
	/* receive interrupt enabled */
	/* RTS low (except if switch selected), transmit interrupt disabled */
	acia.key_ctrl = (ACIA_DIV64\|ACIA_D8N1S\|ACIA_RIE) \|
	((atari_switches & ATARI_SWITCH_IKBD) ?
	ACIA_RHTID : ACIA_RLTID);

	acia.mid_ctrl = ACIA_DIV16 \| ACIA_D8N1S \|
	(atari_switches & ATARI_SWITCH_MIDI) ? ACIA_RHTID : 0;

	/* make sure the interrupt line is up */
	} while ((mfp.par_dt_reg & 0x10) == 0);

	/* enable ACIA Interrupts */
	mfp.active_edge &= ~0x10;
	atari_turnon_irq(IRQ_MFP_ACIA);

	ikbd_self_test = 1;
	ikbd_reset();
	/* wait for a period of inactivity (here: 0.25s), then assume the IKBD's
	* self-test is finished */
	self_test_last_rcv = jiffies;
	while (time_before(jiffies, self_test_last_rcv + HZ/4))
	barrier();
	/* if not incremented: no 0xf1 received */
	if (ikbd_self_test == 1)
	printk(KERN_ERR "WARNING: keyboard self test failed!\n");
	ikbd_self_test = 0;

	ikbd_mouse_disable();
	ikbd_joystick_disable();

	#ifdef FIXED_ATARI_JOYSTICK
	atari_joystick_init();
	#endif

	// flag init done
	atari_keyb_done = 1;
	return 0;
	}

	int atari_kbd_translate(unsigned char keycode, unsigned char *keycodep, char raw_mode)
	{
	#ifdef CONFIG_MAGIC_SYSRQ
	/* ALT+HELP pressed? */
	if ((keycode == 98) && ((shift_state & 0xff) == 8))
	*keycodep = 0xff;
	else
	#endif
	*keycodep = keycode;
	return 1;
	}