drivers/media/radio/miropcm20-rds.c

   1 /* MiroSOUND PCM20 radio rds interface driver
   2  * (c) 2001 Robert Siemer <Robert.Siemer@gmx.de>
   3  * Thanks to Fred Seidel. See miropcm20-rds-core.c for further information.
   4  */
   5
   6 /* Revision history:
   7  *
   8  *   2001-04-18  Robert Siemer <Robert.Siemer@gmx.de>
   9  *        separate file for user interface driver
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/slab.h>
  15 #include <linux/fs.h>
  16 #include <linux/miscdevice.h>
  17 #include <linux/sched.h>        /* current, TASK_*, schedule_timeout() */
  18 #include <linux/delay.h>
  19 #include <asm/uaccess.h>
  20 #include "miropcm20-rds-core.h"
  21
  22 static char * text_buffer;
  23 static int rds_users = 0;
  24
  25
  26 static int rds_f_open(struct inode *in, struct file *fi)
  27 {
  28         if (rds_users)
  29                 return -EBUSY;
  30
  31         rds_users++;
  32         if ((text_buffer=kmalloc(66, GFP_KERNEL)) == 0) {
  33                 rds_users--;
  34                 printk(KERN_NOTICE "aci-rds: Out of memory by open()...\n");
  35                 return -ENOMEM;
  36         }
  37
  38         return 0;
  39 }
  40
  41 static int rds_f_release(struct inode *in, struct file *fi)
  42 {
  43         kfree(text_buffer);
  44
  45         rds_users--;
  46         return 0;
  47 }
  48
  49 static void print_matrix(char *ch, char out[])
  50 {
  51         int j;
  52
  53         for (j=7; j>=0; j--) {
  54                  out[7-j] = ((*ch >> j) & 0x1) + '0';
  55         }
  56 }
  57
  58 static ssize_t rds_f_read(struct file *file, char __user *buffer, size_t length, loff_t *offset)
  59 {
  60 //      i = sprintf(text_buffer, "length: %d, offset: %d\n", length, *offset);
  61
  62         char c;
  63         char bits[8];
  64
  65         msleep(2000);
  66         aci_rds_cmd(RDS_STATUS, &c, 1);
  67         print_matrix(&c, bits);
  68         if (copy_to_user(buffer, bits, 8))
  69                 return -EFAULT;
  70
  71 /*      if ((c >> 3) & 1) {
  72                 aci_rds_cmd(RDS_STATIONNAME, text_buffer+1, 8);
  73                 text_buffer[0]  = ' ' ;
  74                 text_buffer[9]  = '\n';
  75                 return copy_to_user(buffer+8, text_buffer, 10) ? -EFAULT: 18;
  76         }
  77 */
  78 /*      if ((c >> 6) & 1) {
  79                 aci_rds_cmd(RDS_PTYTATP, &c, 1);
  80                 if ( c & 1)
  81                         sprintf(text_buffer, " M");
  82                 else
  83                         sprintf(text_buffer, " S");
  84                 if ((c >> 1) & 1)
  85                         sprintf(text_buffer+2, " TA");
  86                 else
  87                         sprintf(text_buffer+2, " --");
  88                 if ((c >> 7) & 1)
  89                         sprintf(text_buffer+5, " TP");
  90                 else
  91                         sprintf(text_buffer+5, " --");
  92                 sprintf(text_buffer+8, " %2d\n", (c >> 2) & 0x1f);
  93                 return copy_to_user(buffer+8, text_buffer, 12) ? -EFAULT: 20;
  94         }
  95 */
  96
  97         if ((c >> 4) & 1) {
  98                 aci_rds_cmd(RDS_TEXT, text_buffer, 65);
  99                 text_buffer[0]  = ' ' ;
 100                 text_buffer[65] = '\n';
 101                 return copy_to_user(buffer+8, text_buffer,66) ? -EFAULT : 66+8;
 102         } else {
 103                 put_user('\n', buffer+8);
 104                 return 9;
 105         }
 106 }
 107
 108 static struct file_operations rds_fops = {
 109         .owner          = THIS_MODULE,
 110         .read           = rds_f_read,
 111         .open           = rds_f_open,
 112         .release        = rds_f_release
 113 };
 114
 115 static struct miscdevice rds_miscdev = {
 116         .minor          = MISC_DYNAMIC_MINOR,
 117         .name           = "radiotext",
 118         .devfs_name     = "v4l/rds/radiotext",
 119         .fops           = &rds_fops,
 120 };
 121
 122 static int __init miropcm20_rds_init(void)
 123 {
 124         return misc_register(&rds_miscdev);
 125 }
 126
 127 static void __exit miropcm20_rds_cleanup(void)
 128 {
 129         misc_deregister(&rds_miscdev);
 130 }
 131
 132 module_init(miropcm20_rds_init);
 133 module_exit(miropcm20_rds_cleanup);
 134 MODULE_LICENSE("GPL");