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