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