/* * $Id: scan_keyb.c,v 1.2 2000/07/04 06:24:42 yaegashi Exp $ * Copyright (C) 2000 YAEGASHI Takeshi * Generic scan keyboard driver */ #include <linux/spinlock.h> #include <linux/sched.h> #include <linux/interrupt.h> #include <linux/tty.h> #include <linux/mm.h> #include <linux/signal.h> #include <linux/init.h> #include <linux/kbd_ll.h> #include <linux/delay.h> #include <linux/random.h> #include <linux/poll.h> #include <linux/miscdevice.h> #include <linux/slab.h> #include <linux/kbd_kern.h> #include <linux/timer.h> #define SCANHZ (HZ/20) struct scan_keyboard { struct scan_keyboard *next; int (*scan)(unsigned char *buffer); const unsigned char *table; unsigned char *s0, *s1; int length; }; static int scan_jiffies=0; static struct scan_keyboard *keyboards=NULL; struct timer_list scan_timer; static void check_kbd(const unsigned char *table, unsigned char *new, unsigned char *old, int length) { int need_tasklet_schedule=0; unsigned int xor, bit; while(length-->0) { if((xor=*new^*old)==0) { table+=8; } else { for(bit=0x01; bit<0x100; bit<<=1) { if(xor&bit) { handle_scancode(*table, !(*new&bit)); need_tasklet_schedule=1; #if 0 printk("0x%x %s\n", *table, (*new&bit)?"released":"pressed"); #endif } table++; } } new++; old++; } if(need_tasklet_schedule) tasklet_schedule(&keyboard_tasklet); } static void scan_kbd(unsigned long dummy) { struct scan_keyboard *kbd; scan_jiffies++; for(kbd=keyboards; kbd!=NULL; kbd=kbd->next) { if(scan_jiffies&1) { if(!kbd->scan(kbd->s0)) check_kbd(kbd->table, kbd->s0, kbd->s1, kbd->length); else memcpy(kbd->s0, kbd->s1, kbd->length); } else { if(!kbd->scan(kbd->s1)) check_kbd(kbd->table, kbd->s1, kbd->s0, kbd->length); else memcpy(kbd->s1, kbd->s0, kbd->length); } } init_timer(&scan_timer); scan_timer.expires = jiffies + SCANHZ; scan_timer.data = 0; scan_timer.function = scan_kbd; add_timer(&scan_timer); } int register_scan_keyboard(int (*scan)(unsigned char *buffer), const unsigned char *table, int length) { struct scan_keyboard *kbd; kbd = kmalloc(sizeof(struct scan_keyboard), GFP_KERNEL); if (kbd == NULL) goto error_out; kbd->scan=scan; kbd->table=table; kbd->length=length; kbd->s0 = kmalloc(length, GFP_KERNEL); if (kbd->s0 == NULL) goto error_free_kbd; kbd->s1 = kmalloc(length, GFP_KERNEL); if (kbd->s1 == NULL) goto error_free_s0; memset(kbd->s0, -1, kbd->length); memset(kbd->s1, -1, kbd->length); kbd->next=keyboards; keyboards=kbd; return 0; error_free_s0: kfree(kbd->s0); error_free_kbd: kfree(kbd); error_out: return -ENOMEM; } void __init scan_kbd_init(void) { init_timer(&scan_timer); scan_timer.expires = jiffies + SCANHZ; scan_timer.data = 0; scan_timer.function = scan_kbd; add_timer(&scan_timer); printk(KERN_INFO "Generic scan keyboard driver initialized\n"); }