drivers/media/radio/radio-terratec.c

   1 /* Terratec ActiveRadio ISA Standalone card driver for Linux radio support
   2  * (c) 1999 R. Offermanns (rolf@offermanns.de)
   3  * based on the aimslab radio driver from M. Kirkwood
   4  * many thanks to Michael Becker and Friedhelm Birth (from TerraTec)
   5  *
   6  *
   7  * History:
   8  * 1999-05-21   First preview release
   9  *
  10  *  Notes on the hardware:
  11  *  There are two "main" chips on the card:
  12  *  - Philips OM5610 (http://www-us.semiconductors.philips.com/acrobat/datasheets/OM5610_2.pdf)
  13  *  - Philips SAA6588 (http://www-us.semiconductors.philips.com/acrobat/datasheets/SAA6588_1.pdf)
  14  *  (you can get the datasheet at the above links)
  15  *
  16  *  Frequency control is done digitally -- ie out(port,encodefreq(95.8));
  17  *  Volume Control is done digitally
  18  *
  19  * Converted to the radio-isa framework by Hans Verkuil <hans.verkuil@cisco.com>
  20  * Converted to V4L2 API by Mauro Carvalho Chehab <mchehab@infradead.org>
  21  */
  22
  23 #include <linux/module.h>       /* Modules                      */
  24 #include <linux/init.h>         /* Initdata                     */
  25 #include <linux/ioport.h>       /* request_region               */
  26 #include <linux/videodev2.h>    /* kernel radio structs         */
  27 #include <linux/mutex.h>
  28 #include <linux/io.h>           /* outb, outb_p                 */
  29 #include <linux/slab.h>
  30 #include <media/v4l2-device.h>
  31 #include <media/v4l2-ioctl.h>
  32 #include "radio-isa.h"
  33
  34 MODULE_AUTHOR("R. Offermans & others");
  35 MODULE_DESCRIPTION("A driver for the TerraTec ActiveRadio Standalone radio card.");
  36 MODULE_LICENSE("GPL");
  37 MODULE_VERSION("0.1.99");
  38
  39 /* Note: there seems to be only one possible port (0x590), but without
  40    hardware this is hard to verify. For now, this is the only one we will
  41    support. */
  42 static int io = 0x590;
  43 static int radio_nr = -1;
  44
  45 module_param(radio_nr, int, 0444);
  46 MODULE_PARM_DESC(radio_nr, "Radio device number");
  47
  48 #define WRT_DIS         0x00
  49 #define CLK_OFF         0x00
  50 #define IIC_DATA        0x01
  51 #define IIC_CLK         0x02
  52 #define DATA            0x04
  53 #define CLK_ON          0x08
  54 #define WRT_EN          0x10
  55
  56 static struct radio_isa_card *terratec_alloc(void)
  57 {
  58         return kzalloc(sizeof(struct radio_isa_card), GFP_KERNEL);
  59 }
  60
  61 static int terratec_s_mute_volume(struct radio_isa_card *isa, bool mute, int vol)
  62 {
  63         int i;
  64
  65         if (mute)
  66                 vol = 0;
  67         vol = vol + (vol * 32); /* change both channels */
  68         for (i = 0; i < 8; i++) {
  69                 if (vol & (0x80 >> i))
  70                         outb(0x80, isa->io + 1);
  71                 else
  72                         outb(0x00, isa->io + 1);
  73         }
  74         return 0;
  75 }
  76
  77
  78 /* this is the worst part in this driver */
  79 /* many more or less strange things are going on here, but hey, it works :) */
  80
  81 static int terratec_s_frequency(struct radio_isa_card *isa, u32 freq)
  82 {
  83         int i;
  84         int p;
  85         int temp;
  86         long rest;
  87         unsigned char buffer[25];               /* we have to bit shift 25 registers */
  88
  89         freq = freq / 160;                      /* convert the freq. to a nice to handle value */
  90         memset(buffer, 0, sizeof(buffer));
  91
  92         rest = freq * 10 + 10700;       /* I once had understood what is going on here */
  93                                         /* maybe some wise guy (friedhelm?) can comment this stuff */
  94         i = 13;
  95         p = 10;
  96         temp = 102400;
  97         while (rest != 0) {
  98                 if (rest % temp  == rest)
  99                         buffer[i] = 0;
 100                 else {
 101                         buffer[i] = 1;
 102                         rest = rest - temp;
 103                 }
 104                 i--;
 105                 p--;
 106                 temp = temp / 2;
 107         }
 108
 109         for (i = 24; i > -1; i--) {     /* bit shift the values to the radiocard */
 110                 if (buffer[i] == 1) {
 111                         outb(WRT_EN | DATA, isa->io);
 112                         outb(WRT_EN | DATA | CLK_ON, isa->io);
 113                         outb(WRT_EN | DATA, isa->io);
 114                 } else {
 115                         outb(WRT_EN | 0x00, isa->io);
 116                         outb(WRT_EN | 0x00 | CLK_ON, isa->io);
 117                 }
 118         }
 119         outb(0x00, isa->io);
 120         return 0;
 121 }
 122
 123 static u32 terratec_g_signal(struct radio_isa_card *isa)
 124 {
 125         /* bit set = no signal present  */
 126         return (inb(isa->io) & 2) ? 0 : 0xffff;
 127 }
 128
 129 static const struct radio_isa_ops terratec_ops = {
 130         .alloc = terratec_alloc,
 131         .s_mute_volume = terratec_s_mute_volume,
 132         .s_frequency = terratec_s_frequency,
 133         .g_signal = terratec_g_signal,
 134 };
 135
 136 static const int terratec_ioports[] = { 0x590 };
 137
 138 static struct radio_isa_driver terratec_driver = {
 139         .driver = {
 140                 .match          = radio_isa_match,
 141                 .probe          = radio_isa_probe,
 142                 .remove         = radio_isa_remove,
 143                 .driver         = {
 144                         .name   = "radio-terratec",
 145                 },
 146         },
 147         .io_params = &io,
 148         .radio_nr_params = &radio_nr,
 149         .io_ports = terratec_ioports,
 150         .num_of_io_ports = ARRAY_SIZE(terratec_ioports),
 151         .region_size = 2,
 152         .card = "TerraTec ActiveRadio",
 153         .ops = &terratec_ops,
 154         .has_stereo = true,
 155         .max_volume = 10,
 156 };
 157
 158 static int __init terratec_init(void)
 159 {
 160         return isa_register_driver(&terratec_driver.driver, 1);
 161 }
 162
 163 static void __exit terratec_exit(void)
 164 {
 165         isa_unregister_driver(&terratec_driver.driver);
 166 }
 167
 168 module_init(terratec_init);
 169 module_exit(terratec_exit);
 170