drivers/media/radio/radio-terratec.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* Terratec ActiveRadio ISA Standalone card driver for Linux radio support
   3  * (c) 1999 R. Offermanns (rolf@offermanns.de)
   4  * based on the aimslab radio driver from M. Kirkwood
   5  * many thanks to Michael Becker and Friedhelm Birth (from TerraTec)
   6  *
   7  *
   8  * History:
   9  * 1999-05-21   First preview release
  10  *
  11  *  Notes on the hardware:
  12  *  There are two "main" chips on the card:
  13  *  - Philips OM5610 (http://www-us.semiconductors.philips.com/acrobat/datasheets/OM5610_2.pdf)
  14  *  - Philips SAA6588 (http://www-us.semiconductors.philips.com/acrobat/datasheets/SAA6588_1.pdf)
  15  *  (you can get the datasheet at the above links)
  16  *
  17  *  Frequency control is done digitally -- ie out(port,encodefreq(95.8));
  18  *  Volume Control is done digitally
  19  *
  20  * Converted to the radio-isa framework by Hans Verkuil <hans.verkuil@cisco.com>
  21  * Converted to V4L2 API by Mauro Carvalho Chehab <mchehab@kernel.org>
  22  */
  23
  24 #include <linux/module.h>       /* Modules                      */
  25 #include <linux/init.h>         /* Initdata                     */
  26 #include <linux/ioport.h>       /* request_region               */
  27 #include <linux/videodev2.h>    /* kernel radio structs         */
  28 #include <linux/mutex.h>
  29 #include <linux/io.h>           /* outb, outb_p                 */
  30 #include <linux/slab.h>
  31 #include <media/v4l2-device.h>
  32 #include <media/v4l2-ioctl.h>
  33 #include "radio-isa.h"
  34
  35 MODULE_AUTHOR("R. Offermans & others");
  36 MODULE_DESCRIPTION("A driver for the TerraTec ActiveRadio Standalone radio card.");
  37 MODULE_LICENSE("GPL");
  38 MODULE_VERSION("0.1.99");
  39
  40 /* Note: there seems to be only one possible port (0x590), but without
  41    hardware this is hard to verify. For now, this is the only one we will
  42    support. */
  43 static int io = 0x590;
  44 static int radio_nr = -1;
  45
  46 module_param(radio_nr, int, 0444);
  47 MODULE_PARM_DESC(radio_nr, "Radio device number");
  48
  49 #define WRT_DIS         0x00
  50 #define CLK_OFF         0x00
  51 #define IIC_DATA        0x01
  52 #define IIC_CLK         0x02
  53 #define DATA            0x04
  54 #define CLK_ON          0x08
  55 #define WRT_EN          0x10
  56
  57 static struct radio_isa_card *terratec_alloc(void)
  58 {
  59         return kzalloc(sizeof(struct radio_isa_card), GFP_KERNEL);
  60 }
  61
  62 static int terratec_s_mute_volume(struct radio_isa_card *isa, bool mute, int vol)
  63 {
  64         int i;
  65
  66         if (mute)
  67                 vol = 0;
  68         vol = vol + (vol * 32); /* change both channels */
  69         for (i = 0; i < 8; i++) {
  70                 if (vol & (0x80 >> i))
  71                         outb(0x80, isa->io + 1);
  72                 else
  73                         outb(0x00, isa->io + 1);
  74         }
  75         return 0;
  76 }
  77
  78
  79 /* this is the worst part in this driver */
  80 /* many more or less strange things are going on here, but hey, it works :) */
  81
  82 static int terratec_s_frequency(struct radio_isa_card *isa, u32 freq)
  83 {
  84         int i;
  85         int p;
  86         int temp;
  87         long rest;
  88         unsigned char buffer[25];               /* we have to bit shift 25 registers */
  89
  90         freq = freq / 160;                      /* convert the freq. to a nice to handle value */
  91         memset(buffer, 0, sizeof(buffer));
  92
  93         rest = freq * 10 + 10700;       /* I once had understood what is going on here */
  94                                         /* maybe some wise guy (friedhelm?) can comment this stuff */
  95         i = 13;
  96         p = 10;
  97         temp = 102400;
  98         while (rest != 0) {
  99                 if (rest % temp  == rest)
 100                         buffer[i] = 0;
 101                 else {
 102                         buffer[i] = 1;
 103                         rest = rest - temp;
 104                 }
 105                 i--;
 106                 p--;
 107                 temp = temp / 2;
 108         }
 109
 110         for (i = 24; i > -1; i--) {     /* bit shift the values to the radiocard */
 111                 if (buffer[i] == 1) {
 112                         outb(WRT_EN | DATA, isa->io);
 113                         outb(WRT_EN | DATA | CLK_ON, isa->io);
 114                         outb(WRT_EN | DATA, isa->io);
 115                 } else {
 116                         outb(WRT_EN | 0x00, isa->io);
 117                         outb(WRT_EN | 0x00 | CLK_ON, isa->io);
 118                 }
 119         }
 120         outb(0x00, isa->io);
 121         return 0;
 122 }
 123
 124 static u32 terratec_g_signal(struct radio_isa_card *isa)
 125 {
 126         /* bit set = no signal present  */
 127         return (inb(isa->io) & 2) ? 0 : 0xffff;
 128 }
 129
 130 static const struct radio_isa_ops terratec_ops = {
 131         .alloc = terratec_alloc,
 132         .s_mute_volume = terratec_s_mute_volume,
 133         .s_frequency = terratec_s_frequency,
 134         .g_signal = terratec_g_signal,
 135 };
 136
 137 static const int terratec_ioports[] = { 0x590 };
 138
 139 static struct radio_isa_driver terratec_driver = {
 140         .driver = {
 141                 .match          = radio_isa_match,
 142                 .probe          = radio_isa_probe,
 143                 .remove         = radio_isa_remove,
 144                 .driver         = {
 145                         .name   = "radio-terratec",
 146                 },
 147         },
 148         .io_params = &io,
 149         .radio_nr_params = &radio_nr,
 150         .io_ports = terratec_ioports,
 151         .num_of_io_ports = ARRAY_SIZE(terratec_ioports),
 152         .region_size = 2,
 153         .card = "TerraTec ActiveRadio",
 154         .ops = &terratec_ops,
 155         .has_stereo = true,
 156         .max_volume = 10,
 157 };
 158
 159 static int __init terratec_init(void)
 160 {
 161         return isa_register_driver(&terratec_driver.driver, 1);
 162 }
 163
 164 static void __exit terratec_exit(void)
 165 {
 166         isa_unregister_driver(&terratec_driver.driver);
 167 }
 168
 169 module_init(terratec_init);
 170 module_exit(terratec_exit);
 171