drivers/macintosh/ans-lcd.c

   1 /*
   2  * /dev/lcd driver for Apple Network Servers.
   3  */
   4
   5 #include <linux/types.h>
   6 #include <linux/smp_lock.h>
   7 #include <linux/errno.h>
   8 #include <linux/kernel.h>
   9 #include <linux/miscdevice.h>
  10 #include <linux/fcntl.h>
  11 #include <linux/init.h>
  12 #include <linux/delay.h>
  13 #include <linux/fs.h>
  14
  15 #include <asm/uaccess.h>
  16 #include <asm/sections.h>
  17 #include <asm/prom.h>
  18 #include <asm/io.h>
  19
  20 #include "ans-lcd.h"
  21
  22 #define ANSLCD_ADDR             0xf301c000
  23 #define ANSLCD_CTRL_IX 0x00
  24 #define ANSLCD_DATA_IX 0x10
  25
  26 static unsigned long anslcd_short_delay = 80;
  27 static unsigned long anslcd_long_delay = 3280;
  28 static volatile unsigned char __iomem *anslcd_ptr;
  29
  30 #undef DEBUG
  31
  32 static void
  33 anslcd_write_byte_ctrl ( unsigned char c )
  34 {
  35 #ifdef DEBUG
  36         printk(KERN_DEBUG "LCD: CTRL byte: %02x\n",c);
  37 #endif
  38         out_8(anslcd_ptr + ANSLCD_CTRL_IX, c);
  39         switch(c) {
  40                 case 1:
  41                 case 2:
  42                 case 3:
  43                         udelay(anslcd_long_delay); break;
  44                 default: udelay(anslcd_short_delay);
  45         }
  46 }
  47
  48 static void
  49 anslcd_write_byte_data ( unsigned char c )
  50 {
  51         out_8(anslcd_ptr + ANSLCD_DATA_IX, c);
  52         udelay(anslcd_short_delay);
  53 }
  54
  55 static ssize_t
  56 anslcd_write( struct file * file, const char __user * buf,
  57                                 size_t count, loff_t *ppos )
  58 {
  59         const char __user *p = buf;
  60         int i;
  61
  62 #ifdef DEBUG
  63         printk(KERN_DEBUG "LCD: write\n");
  64 #endif
  65
  66         if (!access_ok(VERIFY_READ, buf, count))
  67                 return -EFAULT;
  68         for ( i = *ppos; count > 0; ++i, ++p, --count )
  69         {
  70                 char c;
  71                 __get_user(c, p);
  72                 anslcd_write_byte_data( c );
  73         }
  74         *ppos = i;
  75         return p - buf;
  76 }
  77
  78 static int
  79 anslcd_ioctl( struct inode * inode, struct file * file,
  80                                 unsigned int cmd, unsigned long arg )
  81 {
  82         char ch, __user *temp;
  83
  84 #ifdef DEBUG
  85         printk(KERN_DEBUG "LCD: ioctl(%d,%d)\n",cmd,arg);
  86 #endif
  87
  88         switch ( cmd )
  89         {
  90         case ANSLCD_CLEAR:
  91                 anslcd_write_byte_ctrl ( 0x38 );
  92                 anslcd_write_byte_ctrl ( 0x0f );
  93                 anslcd_write_byte_ctrl ( 0x06 );
  94                 anslcd_write_byte_ctrl ( 0x01 );
  95                 anslcd_write_byte_ctrl ( 0x02 );
  96                 return 0;
  97         case ANSLCD_SENDCTRL:
  98                 temp = (char __user *) arg;
  99                 __get_user(ch, temp);
 100                 for (; ch; temp++) { /* FIXME: This is ugly, but should work, as a \0 byte is not a valid command code */
 101                         anslcd_write_byte_ctrl ( ch );
 102                         __get_user(ch, temp);
 103                 }
 104                 return 0;
 105         case ANSLCD_SETSHORTDELAY:
 106                 if (!capable(CAP_SYS_ADMIN))
 107                         return -EACCES;
 108                 anslcd_short_delay=arg;
 109                 return 0;
 110         case ANSLCD_SETLONGDELAY:
 111                 if (!capable(CAP_SYS_ADMIN))
 112                         return -EACCES;
 113                 anslcd_long_delay=arg;
 114                 return 0;
 115         default:
 116                 return -EINVAL;
 117         }
 118 }
 119
 120 static int
 121 anslcd_open( struct inode * inode, struct file * file )
 122 {
 123         cycle_kernel_lock();
 124         return 0;
 125 }
 126
 127 const struct file_operations anslcd_fops = {
 128         .write  = anslcd_write,
 129         .ioctl  = anslcd_ioctl,
 130         .open   = anslcd_open,
 131 };
 132
 133 static struct miscdevice anslcd_dev = {
 134         ANSLCD_MINOR,
 135         "anslcd",
 136         &anslcd_fops
 137 };
 138
 139 const char anslcd_logo[] =      "********************"  /* Line #1 */
 140                                 "*      LINUX!      *"  /* Line #3 */
 141                                 "*    Welcome to    *"  /* Line #2 */
 142                                 "********************"; /* Line #4 */
 143
 144 static int __init
 145 anslcd_init(void)
 146 {
 147         int a;
 148         int retval;
 149         struct device_node* node;
 150
 151         node = of_find_node_by_name(NULL, "lcd");
 152         if (!node || !node->parent || strcmp(node->parent->name, "gc")) {
 153                 of_node_put(node);
 154                 return -ENODEV;
 155         }
 156         of_node_put(node);
 157
 158         anslcd_ptr = ioremap(ANSLCD_ADDR, 0x20);
 159
 160         retval = misc_register(&anslcd_dev);
 161         if(retval < 0){
 162                 printk(KERN_INFO "LCD: misc_register failed\n");
 163                 iounmap(anslcd_ptr);
 164                 return retval;
 165         }
 166
 167 #ifdef DEBUG
 168         printk(KERN_DEBUG "LCD: init\n");
 169 #endif
 170
 171         anslcd_write_byte_ctrl ( 0x38 );
 172         anslcd_write_byte_ctrl ( 0x0c );
 173         anslcd_write_byte_ctrl ( 0x06 );
 174         anslcd_write_byte_ctrl ( 0x01 );
 175         anslcd_write_byte_ctrl ( 0x02 );
 176         for(a=0;a<80;a++) {
 177                 anslcd_write_byte_data(anslcd_logo[a]);
 178         }
 179         return 0;
 180 }
 181
 182 static void __exit
 183 anslcd_exit(void)
 184 {
 185         misc_deregister(&anslcd_dev);
 186         iounmap(anslcd_ptr);
 187 }
 188
 189 module_init(anslcd_init);
 190 module_exit(anslcd_exit);