diff options
Diffstat (limited to 'drivers/char/scan_keyb.c')
-rw-r--r-- | drivers/char/scan_keyb.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/drivers/char/scan_keyb.c b/drivers/char/scan_keyb.c new file mode 100644 index 000000000000..2b5bb4f5754d --- /dev/null +++ b/drivers/char/scan_keyb.c @@ -0,0 +1,149 @@ +/* + * $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"); +} |