drivers/char/briq_panel.c

   1 /*
   2  * Drivers for the Total Impact PPC based computer "BRIQ"
   3  * by Dr. Karsten Jeppesen
   4  *
   5  */
   6
   7 #include <linux/module.h>
   8
   9 #include <linux/types.h>
  10 #include <linux/errno.h>
  11 #include <linux/sched.h>
  12 #include <linux/tty.h>
  13 #include <linux/timer.h>
  14 #include <linux/config.h>
  15 #include <linux/kernel.h>
  16 #include <linux/wait.h>
  17 #include <linux/string.h>
  18 #include <linux/slab.h>
  19 #include <linux/ioport.h>
  20 #include <linux/delay.h>
  21 #include <linux/miscdevice.h>
  22 #include <linux/fs.h>
  23 #include <linux/mm.h>
  24 #include <linux/init.h>
  25
  26 #include <asm/uaccess.h>
  27 #include <asm/io.h>
  28 #include <asm/prom.h>
  29
  30 #define         BRIQ_PANEL_MINOR        156
  31 #define         BRIQ_PANEL_VFD_IOPORT   0x0390
  32 #define         BRIQ_PANEL_LED_IOPORT   0x0398
  33 #define         BRIQ_PANEL_VER          "1.1 (04/20/2002)"
  34 #define         BRIQ_PANEL_MSG0         "Loading Linux"
  35
  36 static int              vfd_is_open;
  37 static unsigned char    vfd[40];
  38 static int              vfd_cursor;
  39 static unsigned char    ledpb, led;
  40
  41 static void update_vfd(void)
  42 {
  43         int     i;
  44
  45         /* cursor home */
  46         outb(0x02, BRIQ_PANEL_VFD_IOPORT);
  47         for (i=0; i<20; i++)
  48                 outb(vfd[i], BRIQ_PANEL_VFD_IOPORT + 1);
  49
  50         /* cursor to next line */
  51         outb(0xc0, BRIQ_PANEL_VFD_IOPORT);
  52         for (i=20; i<40; i++)
  53                 outb(vfd[i], BRIQ_PANEL_VFD_IOPORT + 1);
  54
  55 }
  56
  57 static void set_led(char state)
  58 {
  59         if (state == 'R')
  60                 led = 0x01;
  61         else if (state == 'G')
  62                 led = 0x02;
  63         else if (state == 'Y')
  64                 led = 0x03;
  65         else if (state == 'X')
  66                 led = 0x00;
  67         outb(led, BRIQ_PANEL_LED_IOPORT);
  68 }
  69
  70 static int briq_panel_open(struct inode *ino, struct file *filep)
  71 {
  72         /* enforce single access */
  73         if (vfd_is_open)
  74                 return -EBUSY;
  75         vfd_is_open = 1;
  76
  77         return 0;
  78 }
  79
  80 static int briq_panel_release(struct inode *ino, struct file *filep)
  81 {
  82         if (!vfd_is_open)
  83                 return -ENODEV;
  84
  85         vfd_is_open = 0;
  86
  87         return 0;
  88 }
  89
  90 static ssize_t briq_panel_read(struct file *file, char __user *buf, size_t count,
  91                          loff_t *ppos)
  92 {
  93         unsigned short c;
  94         unsigned char cp;
  95
  96 #if 0   /*  Can't seek (pread) on this device  */
  97         if (ppos != &file->f_pos)
  98                 return -ESPIPE;
  99 #endif
 100
 101         if (!vfd_is_open)
 102                 return -ENODEV;
 103
 104         c = (inb(BRIQ_PANEL_LED_IOPORT) & 0x000c) | (ledpb & 0x0003);
 105         set_led(' ');
 106         /* upper button released */
 107         if ((!(ledpb & 0x0004)) && (c & 0x0004)) {
 108                 cp = ' ';
 109                 ledpb = c;
 110                 if (copy_to_user(buf, &cp, 1))
 111                         return -EFAULT;
 112                 return 1;
 113         }
 114         /* lower button released */
 115         else if ((!(ledpb & 0x0008)) && (c & 0x0008)) {
 116                 cp = '\r';
 117                 ledpb = c;
 118                 if (copy_to_user(buf, &cp, 1))
 119                         return -EFAULT;
 120                 return 1;
 121         } else {
 122                 ledpb = c;
 123                 return 0;
 124         }
 125 }
 126
 127 static void scroll_vfd( void )
 128 {
 129         int     i;
 130
 131         for (i=0; i<20; i++) {
 132                 vfd[i] = vfd[i+20];
 133                 vfd[i+20] = ' ';
 134         }
 135         vfd_cursor = 20;
 136 }
 137
 138 static ssize_t briq_panel_write(struct file *file, const char __user *buf, size_t len,
 139                           loff_t *ppos)
 140 {
 141         size_t indx = len;
 142         int i, esc = 0;
 143
 144 #if 0   /*  Can't seek (pwrite) on this device  */
 145         if (ppos != &file->f_pos)
 146                 return -ESPIPE;
 147 #endif
 148
 149         if (!vfd_is_open)
 150                 return -EBUSY;
 151
 152         for (;;) {
 153                 char c;
 154                 if (!indx)
 155                         break;
 156                 if (get_user(c, buf))
 157                         return -EFAULT;
 158                 if (esc) {
 159                         set_led(c);
 160                         esc = 0;
 161                 } else if (c == 27) {
 162                         esc = 1;
 163                 } else if (c == 12) {
 164                         /* do a form feed */
 165                         for (i=0; i<40; i++)
 166                                 vfd[i] = ' ';
 167                         vfd_cursor = 0;
 168                 } else if (c == 10) {
 169                         if (vfd_cursor < 20)
 170                                 vfd_cursor = 20;
 171                         else if (vfd_cursor < 40)
 172                                 vfd_cursor = 40;
 173                         else if (vfd_cursor < 60)
 174                                 vfd_cursor = 60;
 175                         if (vfd_cursor > 59)
 176                                 scroll_vfd();
 177                 } else {
 178                         /* just a character */
 179                         if (vfd_cursor > 39)
 180                                 scroll_vfd();
 181                         vfd[vfd_cursor++] = c;
 182                 }
 183                 indx--;
 184                 buf++;
 185         }
 186         update_vfd();
 187
 188         return len;
 189 }
 190
 191 static struct file_operations briq_panel_fops = {
 192         .owner          = THIS_MODULE,
 193         .read           = briq_panel_read,
 194         .write          = briq_panel_write,
 195         .open           = briq_panel_open,
 196         .release        = briq_panel_release,
 197 };
 198
 199 static struct miscdevice briq_panel_miscdev = {
 200         BRIQ_PANEL_MINOR,
 201         "briq_panel",
 202         &briq_panel_fops
 203 };
 204
 205 static int __init briq_panel_init(void)
 206 {
 207         struct device_node *root = find_path_device("/");
 208         const char *machine;
 209         int i;
 210
 211         machine = get_property(root, "model", NULL);
 212         if (!machine || strncmp(machine, "TotalImpact,BRIQ-1", 18) != 0)
 213                 return -ENODEV;
 214
 215         printk(KERN_INFO
 216                 "briq_panel: v%s Dr. Karsten Jeppesen (kj@totalimpact.com)\n",
 217                 BRIQ_PANEL_VER);
 218
 219         if (!request_region(BRIQ_PANEL_VFD_IOPORT, 4, "BRIQ Front Panel"))
 220                 return -EBUSY;
 221
 222         if (!request_region(BRIQ_PANEL_LED_IOPORT, 2, "BRIQ Front Panel")) {
 223                 release_region(BRIQ_PANEL_VFD_IOPORT, 4);
 224                 return -EBUSY;
 225         }
 226         ledpb = inb(BRIQ_PANEL_LED_IOPORT) & 0x000c;
 227
 228         if (misc_register(&briq_panel_miscdev) < 0) {
 229                 release_region(BRIQ_PANEL_VFD_IOPORT, 4);
 230                 release_region(BRIQ_PANEL_LED_IOPORT, 2);
 231                 return -EBUSY;
 232         }
 233
 234         outb(0x38, BRIQ_PANEL_VFD_IOPORT);      /* Function set */
 235         outb(0x01, BRIQ_PANEL_VFD_IOPORT);      /* Clear display */
 236         outb(0x0c, BRIQ_PANEL_VFD_IOPORT);      /* Display on */
 237         outb(0x06, BRIQ_PANEL_VFD_IOPORT);      /* Entry normal */
 238         for (i=0; i<40; i++)
 239                 vfd[i]=' ';
 240 #ifndef MODULE
 241         vfd[0] = 'L';
 242         vfd[1] = 'o';
 243         vfd[2] = 'a';
 244         vfd[3] = 'd';
 245         vfd[4] = 'i';
 246         vfd[5] = 'n';
 247         vfd[6] = 'g';
 248         vfd[7] = ' ';
 249         vfd[8] = '.';
 250         vfd[9] = '.';
 251         vfd[10] = '.';
 252 #endif /* !MODULE */
 253
 254         update_vfd();
 255
 256         return 0;
 257 }
 258
 259 static void __exit briq_panel_exit(void)
 260 {
 261         misc_deregister(&briq_panel_miscdev);
 262         release_region(BRIQ_PANEL_VFD_IOPORT, 4);
 263         release_region(BRIQ_PANEL_LED_IOPORT, 2);
 264 }
 265
 266 module_init(briq_panel_init);
 267 module_exit(briq_panel_exit);
 268
 269 MODULE_LICENSE("GPL");
 270 MODULE_AUTHOR("Karsten Jeppesen <karsten@jeppesens.com>");
 271 MODULE_DESCRIPTION("Driver for the Total Impact briQ front panel");