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/tty.h>
  12 #include <linux/timer.h>
  13 #include <linux/kernel.h>
  14 #include <linux/wait.h>
  15 #include <linux/string.h>
  16 #include <linux/slab.h>
  17 #include <linux/ioport.h>
  18 #include <linux/delay.h>
  19 #include <linux/miscdevice.h>
  20 #include <linux/fs.h>
  21 #include <linux/mm.h>
  22 #include <linux/init.h>
  23
  24 #include <asm/uaccess.h>
  25 #include <asm/io.h>
  26 #include <asm/prom.h>
  27
  28 #define         BRIQ_PANEL_MINOR        156
  29 #define         BRIQ_PANEL_VFD_IOPORT   0x0390
  30 #define         BRIQ_PANEL_LED_IOPORT   0x0398
  31 #define         BRIQ_PANEL_VER          "1.1 (04/20/2002)"
  32 #define         BRIQ_PANEL_MSG0         "Loading Linux"
  33
  34 static int              vfd_is_open;
  35 static unsigned char    vfd[40];
  36 static int              vfd_cursor;
  37 static unsigned char    ledpb, led;
  38
  39 static void update_vfd(void)
  40 {
  41         int     i;
  42
  43         /* cursor home */
  44         outb(0x02, BRIQ_PANEL_VFD_IOPORT);
  45         for (i=0; i<20; i++)
  46                 outb(vfd[i], BRIQ_PANEL_VFD_IOPORT + 1);
  47
  48         /* cursor to next line */
  49         outb(0xc0, BRIQ_PANEL_VFD_IOPORT);
  50         for (i=20; i<40; i++)
  51                 outb(vfd[i], BRIQ_PANEL_VFD_IOPORT + 1);
  52
  53 }
  54
  55 static void set_led(char state)
  56 {
  57         if (state == 'R')
  58                 led = 0x01;
  59         else if (state == 'G')
  60                 led = 0x02;
  61         else if (state == 'Y')
  62                 led = 0x03;
  63         else if (state == 'X')
  64                 led = 0x00;
  65         outb(led, BRIQ_PANEL_LED_IOPORT);
  66 }
  67
  68 static int briq_panel_open(struct inode *ino, struct file *filep)
  69 {
  70         /* enforce single access */
  71         if (vfd_is_open)
  72                 return -EBUSY;
  73         vfd_is_open = 1;
  74
  75         return 0;
  76 }
  77
  78 static int briq_panel_release(struct inode *ino, struct file *filep)
  79 {
  80         if (!vfd_is_open)
  81                 return -ENODEV;
  82
  83         vfd_is_open = 0;
  84
  85         return 0;
  86 }
  87
  88 static ssize_t briq_panel_read(struct file *file, char __user *buf, size_t count,
  89                          loff_t *ppos)
  90 {
  91         unsigned short c;
  92         unsigned char cp;
  93
  94         if (!vfd_is_open)
  95                 return -ENODEV;
  96
  97         c = (inb(BRIQ_PANEL_LED_IOPORT) & 0x000c) | (ledpb & 0x0003);
  98         set_led(' ');
  99         /* upper button released */
 100         if ((!(ledpb & 0x0004)) && (c & 0x0004)) {
 101                 cp = ' ';
 102                 ledpb = c;
 103                 if (copy_to_user(buf, &cp, 1))
 104                         return -EFAULT;
 105                 return 1;
 106         }
 107         /* lower button released */
 108         else if ((!(ledpb & 0x0008)) && (c & 0x0008)) {
 109                 cp = '\r';
 110                 ledpb = c;
 111                 if (copy_to_user(buf, &cp, 1))
 112                         return -EFAULT;
 113                 return 1;
 114         } else {
 115                 ledpb = c;
 116                 return 0;
 117         }
 118 }
 119
 120 static void scroll_vfd( void )
 121 {
 122         int     i;
 123
 124         for (i=0; i<20; i++) {
 125                 vfd[i] = vfd[i+20];
 126                 vfd[i+20] = ' ';
 127         }
 128         vfd_cursor = 20;
 129 }
 130
 131 static ssize_t briq_panel_write(struct file *file, const char __user *buf, size_t len,
 132                           loff_t *ppos)
 133 {
 134         size_t indx = len;
 135         int i, esc = 0;
 136
 137         if (!vfd_is_open)
 138                 return -EBUSY;
 139
 140         for (;;) {
 141                 char c;
 142                 if (!indx)
 143                         break;
 144                 if (get_user(c, buf))
 145                         return -EFAULT;
 146                 if (esc) {
 147                         set_led(c);
 148                         esc = 0;
 149                 } else if (c == 27) {
 150                         esc = 1;
 151                 } else if (c == 12) {
 152                         /* do a form feed */
 153                         for (i=0; i<40; i++)
 154                                 vfd[i] = ' ';
 155                         vfd_cursor = 0;
 156                 } else if (c == 10) {
 157                         if (vfd_cursor < 20)
 158                                 vfd_cursor = 20;
 159                         else if (vfd_cursor < 40)
 160                                 vfd_cursor = 40;
 161                         else if (vfd_cursor < 60)
 162                                 vfd_cursor = 60;
 163                         if (vfd_cursor > 59)
 164                                 scroll_vfd();
 165                 } else {
 166                         /* just a character */
 167                         if (vfd_cursor > 39)
 168                                 scroll_vfd();
 169                         vfd[vfd_cursor++] = c;
 170                 }
 171                 indx--;
 172                 buf++;
 173         }
 174         update_vfd();
 175
 176         return len;
 177 }
 178
 179 static const struct file_operations briq_panel_fops = {
 180         .owner          = THIS_MODULE,
 181         .read           = briq_panel_read,
 182         .write          = briq_panel_write,
 183         .open           = briq_panel_open,
 184         .release        = briq_panel_release,
 185 };
 186
 187 static struct miscdevice briq_panel_miscdev = {
 188         BRIQ_PANEL_MINOR,
 189         "briq_panel",
 190         &briq_panel_fops
 191 };
 192
 193 static int __init briq_panel_init(void)
 194 {
 195         struct device_node *root = of_find_node_by_path("/");
 196         const char *machine;
 197         int i;
 198
 199         machine = of_get_property(root, "model", NULL);
 200         if (!machine || strncmp(machine, "TotalImpact,BRIQ-1", 18) != 0) {
 201                 of_node_put(root);
 202                 return -ENODEV;
 203         }
 204         of_node_put(root);
 205
 206         printk(KERN_INFO
 207                 "briq_panel: v%s Dr. Karsten Jeppesen (kj@totalimpact.com)\n",
 208                 BRIQ_PANEL_VER);
 209
 210         if (!request_region(BRIQ_PANEL_VFD_IOPORT, 4, "BRIQ Front Panel"))
 211                 return -EBUSY;
 212
 213         if (!request_region(BRIQ_PANEL_LED_IOPORT, 2, "BRIQ Front Panel")) {
 214                 release_region(BRIQ_PANEL_VFD_IOPORT, 4);
 215                 return -EBUSY;
 216         }
 217         ledpb = inb(BRIQ_PANEL_LED_IOPORT) & 0x000c;
 218
 219         if (misc_register(&briq_panel_miscdev) < 0) {
 220                 release_region(BRIQ_PANEL_VFD_IOPORT, 4);
 221                 release_region(BRIQ_PANEL_LED_IOPORT, 2);
 222                 return -EBUSY;
 223         }
 224
 225         outb(0x38, BRIQ_PANEL_VFD_IOPORT);      /* Function set */
 226         outb(0x01, BRIQ_PANEL_VFD_IOPORT);      /* Clear display */
 227         outb(0x0c, BRIQ_PANEL_VFD_IOPORT);      /* Display on */
 228         outb(0x06, BRIQ_PANEL_VFD_IOPORT);      /* Entry normal */
 229         for (i=0; i<40; i++)
 230                 vfd[i]=' ';
 231 #ifndef MODULE
 232         vfd[0] = 'L';
 233         vfd[1] = 'o';
 234         vfd[2] = 'a';
 235         vfd[3] = 'd';
 236         vfd[4] = 'i';
 237         vfd[5] = 'n';
 238         vfd[6] = 'g';
 239         vfd[7] = ' ';
 240         vfd[8] = '.';
 241         vfd[9] = '.';
 242         vfd[10] = '.';
 243 #endif /* !MODULE */
 244
 245         update_vfd();
 246
 247         return 0;
 248 }
 249
 250 static void __exit briq_panel_exit(void)
 251 {
 252         misc_deregister(&briq_panel_miscdev);
 253         release_region(BRIQ_PANEL_VFD_IOPORT, 4);
 254         release_region(BRIQ_PANEL_LED_IOPORT, 2);
 255 }
 256
 257 module_init(briq_panel_init);
 258 module_exit(briq_panel_exit);
 259
 260 MODULE_LICENSE("GPL");
 261 MODULE_AUTHOR("Karsten Jeppesen <karsten@jeppesens.com>");
 262 MODULE_DESCRIPTION("Driver for the Total Impact briQ front panel");