drivers/macintosh/ans-lcd.c

   1 /*
   2  * /dev/lcd driver for Apple Network Servers.
   3  */
   4
   5 #include <linux/types.h>
   6 #include <linux/errno.h>
   7 #include <linux/kernel.h>
   8 #include <linux/miscdevice.h>
   9 #include <linux/fcntl.h>
  10 #include <linux/init.h>
  11 #include <linux/delay.h>
  12 #include <linux/fs.h>
  13
  14 #include <asm/uaccess.h>
  15 #include <asm/sections.h>
  16 #include <asm/prom.h>
  17 #include <asm/ans-lcd.h>
  18 #include <asm/io.h>
  19
  20 #define ANSLCD_ADDR             0xf301c000
  21 #define ANSLCD_CTRL_IX 0x00
  22 #define ANSLCD_DATA_IX 0x10
  23
  24 static unsigned long anslcd_short_delay = 80;
  25 static unsigned long anslcd_long_delay = 3280;
  26 static volatile unsigned char __iomem *anslcd_ptr;
  27
  28 #undef DEBUG
  29
  30 static void
  31 anslcd_write_byte_ctrl ( unsigned char c )
  32 {
  33 #ifdef DEBUG
  34         printk(KERN_DEBUG "LCD: CTRL byte: %02x\n",c);
  35 #endif
  36         out_8(anslcd_ptr + ANSLCD_CTRL_IX, c);
  37         switch(c) {
  38                 case 1:
  39                 case 2:
  40                 case 3:
  41                         udelay(anslcd_long_delay); break;
  42                 default: udelay(anslcd_short_delay);
  43         }
  44 }
  45
  46 static void
  47 anslcd_write_byte_data ( unsigned char c )
  48 {
  49         out_8(anslcd_ptr + ANSLCD_DATA_IX, c);
  50         udelay(anslcd_short_delay);
  51 }
  52
  53 static ssize_t
  54 anslcd_write( struct file * file, const char __user * buf,
  55                                 size_t count, loff_t *ppos )
  56 {
  57         const char __user *p = buf;
  58         int i;
  59
  60 #ifdef DEBUG
  61         printk(KERN_DEBUG "LCD: write\n");
  62 #endif
  63
  64         if (!access_ok(VERIFY_READ, buf, count))
  65                 return -EFAULT;
  66         for ( i = *ppos; count > 0; ++i, ++p, --count )
  67         {
  68                 char c;
  69                 __get_user(c, p);
  70                 anslcd_write_byte_data( c );
  71         }
  72         *ppos = i;
  73         return p - buf;
  74 }
  75
  76 static int
  77 anslcd_ioctl( struct inode * inode, struct file * file,
  78                                 unsigned int cmd, unsigned long arg )
  79 {
  80         char ch, __user *temp;
  81
  82 #ifdef DEBUG
  83         printk(KERN_DEBUG "LCD: ioctl(%d,%d)\n",cmd,arg);
  84 #endif
  85
  86         switch ( cmd )
  87         {
  88         case ANSLCD_CLEAR:
  89                 anslcd_write_byte_ctrl ( 0x38 );
  90                 anslcd_write_byte_ctrl ( 0x0f );
  91                 anslcd_write_byte_ctrl ( 0x06 );
  92                 anslcd_write_byte_ctrl ( 0x01 );
  93                 anslcd_write_byte_ctrl ( 0x02 );
  94                 return 0;
  95         case ANSLCD_SENDCTRL:
  96                 temp = (char __user *) arg;
  97                 __get_user(ch, temp);
  98                 for (; ch; temp++) { /* FIXME: This is ugly, but should work, as a \0 byte is not a valid command code */
  99                         anslcd_write_byte_ctrl ( ch );
 100                         __get_user(ch, temp);
 101                 }
 102                 return 0;
 103         case ANSLCD_SETSHORTDELAY:
 104                 if (!capable(CAP_SYS_ADMIN))
 105                         return -EACCES;
 106                 anslcd_short_delay=arg;
 107                 return 0;
 108         case ANSLCD_SETLONGDELAY:
 109                 if (!capable(CAP_SYS_ADMIN))
 110                         return -EACCES;
 111                 anslcd_long_delay=arg;
 112                 return 0;
 113         default:
 114                 return -EINVAL;
 115         }
 116 }
 117
 118 static int
 119 anslcd_open( struct inode * inode, struct file * file )
 120 {
 121         return 0;
 122 }
 123
 124 struct file_operations anslcd_fops = {
 125         .write  = anslcd_write,
 126         .ioctl  = anslcd_ioctl,
 127         .open   = anslcd_open,
 128 };
 129
 130 static struct miscdevice anslcd_dev = {
 131         ANSLCD_MINOR,
 132         "anslcd",
 133         &anslcd_fops
 134 };
 135
 136 const char anslcd_logo[] =      "********************"  /* Line #1 */
 137                                 "*      LINUX!      *"  /* Line #3 */
 138                                 "*    Welcome to    *"  /* Line #2 */
 139                                 "********************"; /* Line #4 */
 140
 141 static int __init
 142 anslcd_init(void)
 143 {
 144         int a;
 145         int retval;
 146         struct device_node* node;
 147
 148         node = find_devices("lcd");
 149         if (!node || !node->parent)
 150                 return -ENODEV;
 151         if (strcmp(node->parent->name, "gc"))
 152                 return -ENODEV;
 153
 154         anslcd_ptr = ioremap(ANSLCD_ADDR, 0x20);
 155
 156         retval = misc_register(&anslcd_dev);
 157         if(retval < 0){
 158                 printk(KERN_INFO "LCD: misc_register failed\n");
 159                 iounmap(anslcd_ptr);
 160                 return retval;
 161         }
 162
 163 #ifdef DEBUG
 164         printk(KERN_DEBUG "LCD: init\n");
 165 #endif
 166
 167         anslcd_write_byte_ctrl ( 0x38 );
 168         anslcd_write_byte_ctrl ( 0x0c );
 169         anslcd_write_byte_ctrl ( 0x06 );
 170         anslcd_write_byte_ctrl ( 0x01 );
 171         anslcd_write_byte_ctrl ( 0x02 );
 172         for(a=0;a<80;a++) {
 173                 anslcd_write_byte_data(anslcd_logo[a]);
 174         }
 175         return 0;
 176 }
 177
 178 static void __exit
 179 anslcd_exit(void)
 180 {
 181         misc_deregister(&anslcd_dev);
 182         iounmap(anslcd_ptr);
 183 }
 184
 185 module_init(anslcd_init);
 186 module_exit(anslcd_exit);