text: /*
   * /dev/lcd driver for Apple Network Servers.
   */
  
  #include <linux/types.h>
  #include <linux/errno.h>
  #include <linux/kernel.h>
  #include <linux/miscdevice.h>
  #include <linux/fcntl.h>
  #include <linux/init.h>
  #include <linux/delay.h>
  #include <linux/fs.h>
  
  #include <asm/uaccess.h>
  #include <asm/sections.h>
  #include <asm/prom.h>
  #include <asm/ans-lcd.h>
  #include <asm/io.h>
  
  #define ANSLCD_ADDR		0xf301c000
  #define ANSLCD_CTRL_IX 0x00
  #define ANSLCD_DATA_IX 0x10
  
  static unsigned long anslcd_short_delay = 80;
  static unsigned long anslcd_long_delay = 3280;
  static volatile unsigned char __iomem *anslcd_ptr;
  
  #undef DEBUG
  
  static void
  anslcd_write_byte_ctrl ( unsigned char c )
  {
  #ifdef DEBUG
  	printk(KERN_DEBUG "LCD: CTRL byte: %02x\n",c);
  #endif
  	out_8(anslcd_ptr + ANSLCD_CTRL_IX, c);
  	switch(c) {
  		case 1:
  		case 2:
  		case 3:
  			udelay(anslcd_long_delay); break;
  		default: udelay(anslcd_short_delay);
  	}
  }
  
  static void
  anslcd_write_byte_data ( unsigned char c )
  {
  	out_8(anslcd_ptr + ANSLCD_DATA_IX, c);
  	udelay(anslcd_short_delay);
  }
  
  static ssize_t
  anslcd_write( struct file * file, const char __user * buf, 
  				size_t count, loff_t *ppos )
  {
  	const char __user *p = buf;
  	int i;
  
  #ifdef DEBUG
  	printk(KERN_DEBUG "LCD: write\n");
  #endif
  
  	if (!access_ok(VERIFY_READ, buf, count))
  		return -EFAULT;
  	for ( i = *ppos; count > 0; ++i, ++p, --count ) 
  	{
  		char c;
  		__get_user(c, p);
  		anslcd_write_byte_data( c );
  	}
  	*ppos = i;
  	return p - buf;
  }
  
  static int
  anslcd_ioctl( struct inode * inode, struct file * file,
  				unsigned int cmd, unsigned long arg )
  {
  	char ch, __user *temp;
  
  #ifdef DEBUG
  	printk(KERN_DEBUG "LCD: ioctl(%d,%d)\n",cmd,arg);
  #endif
  
  	switch ( cmd )
  	{
  	case ANSLCD_CLEAR:
  		anslcd_write_byte_ctrl ( 0x38 );
  		anslcd_write_byte_ctrl ( 0x0f );
  		anslcd_write_byte_ctrl ( 0x06 );
  		anslcd_write_byte_ctrl ( 0x01 );
  		anslcd_write_byte_ctrl ( 0x02 );
  		return 0;
  	case ANSLCD_SENDCTRL:
  		temp = (char __user *) arg;
  		__get_user(ch, temp);
  		for (; ch; temp++) { /* FIXME: This is ugly, but should work, as a \0 byte is not a valid command code */
  			anslcd_write_byte_ctrl ( ch );
  			__get_user(ch, temp);
  		}
  		return 0;
  	case ANSLCD_SETSHORTDELAY:
  		if (!capable(CAP_SYS_ADMIN))
  			return -EACCES;
  		anslcd_short_delay=arg;
  		return 0;
  	case ANSLCD_SETLONGDELAY:
  		if (!capable(CAP_SYS_ADMIN))
  			return -EACCES;
  		anslcd_long_delay=arg;
  		return 0;
  	default:
  		return -EINVAL;
  	}
  }
  
  static int
  anslcd_open( struct inode * inode, struct file * file )
  {
  	return 0;
  }
  
  const struct file_operations anslcd_fops = {
  	.write	= anslcd_write,
  	.ioctl	= anslcd_ioctl,
  	.open	= anslcd_open,
  };
  
  static struct miscdevice anslcd_dev = {
  	ANSLCD_MINOR,
  	"anslcd",
  	&anslcd_fops
  };
  
  const char anslcd_logo[] =	"********************"  /* Line #1 */
  				"*      LINUX!      *"  /* Line #3 */
  				"*    Welcome to    *"  /* Line #2 */
  				"********************"; /* Line #4 */
  
  static int __init
  anslcd_init(void)
  {
  	int a;
  	int retval;
  	struct device_node* node;
  
  	node = find_devices("lcd");
  	if (!node || !node->parent)
  		return -ENODEV;
  	if (strcmp(node->parent->name, "gc"))
  		return -ENODEV;
  
  	anslcd_ptr = ioremap(ANSLCD_ADDR, 0x20);
  	
  	retval = misc_register(&anslcd_dev);
  	if(retval < 0){
  		printk(KERN_INFO "LCD: misc_register failed\n");
  		iounmap(anslcd_ptr);
  		return retval;
  	}
  
  #ifdef DEBUG
  	printk(KERN_DEBUG "LCD: init\n");
  #endif
  
  	anslcd_write_byte_ctrl ( 0x38 );
  	anslcd_write_byte_ctrl ( 0x0c );
  	anslcd_write_byte_ctrl ( 0x06 );
  	anslcd_write_byte_ctrl ( 0x01 );
  	anslcd_write_byte_ctrl ( 0x02 );
  	for(a=0;a<80;a++) {
  		anslcd_write_byte_data(anslcd_logo[a]);
  	}
  	return 0;
  }
  
  static void __exit
  anslcd_exit(void)
  {
  	misc_deregister(&anslcd_dev);
  	iounmap(anslcd_ptr);
  }
  
  module_init(anslcd_init);
  module_exit(anslcd_exit);
  