drivers/media/radio/radio-zoltrix.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Zoltrix Radio Plus driver
   4  * Copyright 1998 C. van Schaik <carl@leg.uct.ac.za>
   5  *
   6  * BUGS
   7  *  Due to the inconsistency in reading from the signal flags
   8  *  it is difficult to get an accurate tuned signal.
   9  *
  10  *  It seems that the card is not linear to 0 volume. It cuts off
  11  *  at a low volume, and it is not possible (at least I have not found)
  12  *  to get fine volume control over the low volume range.
  13  *
  14  *  Some code derived from code by Romolo Manfredini
  15  *                                 romolo@bicnet.it
  16  *
  17  * 1999-05-06 - (C. van Schaik)
  18  *            - Make signal strength and stereo scans
  19  *              kinder to cpu while in delay
  20  * 1999-01-05 - (C. van Schaik)
  21  *            - Changed tuning to 1/160Mhz accuracy
  22  *            - Added stereo support
  23  *              (card defaults to stereo)
  24  *              (can explicitly force mono on the card)
  25  *              (can detect if station is in stereo)
  26  *            - Added unmute function
  27  *            - Reworked ioctl functions
  28  * 2002-07-15 - Fix Stereo typo
  29  *
  30  * 2006-07-24 - Converted to V4L2 API
  31  *              by Mauro Carvalho Chehab <mchehab@kernel.org>
  32  *
  33  * Converted to the radio-isa framework by Hans Verkuil <hans.verkuil@cisco.com>
  34  *
  35  * Note that this is the driver for the Zoltrix Radio Plus.
  36  * This driver does not work for the Zoltrix Radio Plus 108 or the
  37  * Zoltrix Radio Plus for Windows.
  38  *
  39  * Fully tested with the Keene USB FM Transmitter and the v4l2-compliance tool.
  40  */
  41
  42 #include <linux/module.h>       /* Modules                        */
  43 #include <linux/init.h>         /* Initdata                       */
  44 #include <linux/ioport.h>       /* request_region                 */
  45 #include <linux/delay.h>        /* udelay, msleep                 */
  46 #include <linux/videodev2.h>    /* kernel radio structs           */
  47 #include <linux/mutex.h>
  48 #include <linux/io.h>           /* outb, outb_p                   */
  49 #include <linux/slab.h>
  50 #include <media/v4l2-device.h>
  51 #include <media/v4l2-ioctl.h>
  52 #include "radio-isa.h"
  53
  54 MODULE_AUTHOR("C. van Schaik");
  55 MODULE_DESCRIPTION("A driver for the Zoltrix Radio Plus.");
  56 MODULE_LICENSE("GPL");
  57 MODULE_VERSION("0.1.99");
  58
  59 #ifndef CONFIG_RADIO_ZOLTRIX_PORT
  60 #define CONFIG_RADIO_ZOLTRIX_PORT -1
  61 #endif
  62
  63 #define ZOLTRIX_MAX 2
  64
  65 static int io[ZOLTRIX_MAX] = { [0] = CONFIG_RADIO_ZOLTRIX_PORT,
  66                                [1 ... (ZOLTRIX_MAX - 1)] = -1 };
  67 static int radio_nr[ZOLTRIX_MAX] = { [0 ... (ZOLTRIX_MAX - 1)] = -1 };
  68
  69 module_param_array(io, int, NULL, 0444);
  70 MODULE_PARM_DESC(io, "I/O addresses of the Zoltrix Radio Plus card (0x20c or 0x30c)");
  71 module_param_array(radio_nr, int, NULL, 0444);
  72 MODULE_PARM_DESC(radio_nr, "Radio device numbers");
  73
  74 struct zoltrix {
  75         struct radio_isa_card isa;
  76         int curvol;
  77         bool muted;
  78 };
  79
  80 static struct radio_isa_card *zoltrix_alloc(void)
  81 {
  82         struct zoltrix *zol = kzalloc(sizeof(*zol), GFP_KERNEL);
  83
  84         return zol ? &zol->isa : NULL;
  85 }
  86
  87 static int zoltrix_s_mute_volume(struct radio_isa_card *isa, bool mute, int vol)
  88 {
  89         struct zoltrix *zol = container_of(isa, struct zoltrix, isa);
  90
  91         zol->curvol = vol;
  92         zol->muted = mute;
  93         if (mute || vol == 0) {
  94                 outb(0, isa->io);
  95                 outb(0, isa->io);
  96                 inb(isa->io + 3);            /* Zoltrix needs to be read to confirm */
  97                 return 0;
  98         }
  99
 100         outb(vol - 1, isa->io);
 101         msleep(10);
 102         inb(isa->io + 2);
 103         return 0;
 104 }
 105
 106 /* tunes the radio to the desired frequency */
 107 static int zoltrix_s_frequency(struct radio_isa_card *isa, u32 freq)
 108 {
 109         struct zoltrix *zol = container_of(isa, struct zoltrix, isa);
 110         struct v4l2_device *v4l2_dev = &isa->v4l2_dev;
 111         unsigned long long bitmask, f, m;
 112         bool stereo = isa->stereo;
 113         int i;
 114
 115         if (freq == 0) {
 116                 v4l2_warn(v4l2_dev, "cannot set a frequency of 0.\n");
 117                 return -EINVAL;
 118         }
 119
 120         m = (freq / 160 - 8800) * 2;
 121         f = (unsigned long long)m + 0x4d1c;
 122
 123         bitmask = 0xc480402c10080000ull;
 124         i = 45;
 125
 126         outb(0, isa->io);
 127         outb(0, isa->io);
 128         inb(isa->io + 3);            /* Zoltrix needs to be read to confirm */
 129
 130         outb(0x40, isa->io);
 131         outb(0xc0, isa->io);
 132
 133         bitmask = (bitmask ^ ((f & 0xff) << 47) ^ ((f & 0xff00) << 30) ^ (stereo << 31));
 134         while (i--) {
 135                 if ((bitmask & 0x8000000000000000ull) != 0) {
 136                         outb(0x80, isa->io);
 137                         udelay(50);
 138                         outb(0x00, isa->io);
 139                         udelay(50);
 140                         outb(0x80, isa->io);
 141                         udelay(50);
 142                 } else {
 143                         outb(0xc0, isa->io);
 144                         udelay(50);
 145                         outb(0x40, isa->io);
 146                         udelay(50);
 147                         outb(0xc0, isa->io);
 148                         udelay(50);
 149                 }
 150                 bitmask *= 2;
 151         }
 152         /* termination sequence */
 153         outb(0x80, isa->io);
 154         outb(0xc0, isa->io);
 155         outb(0x40, isa->io);
 156         udelay(1000);
 157         inb(isa->io + 2);
 158         udelay(1000);
 159
 160         return zoltrix_s_mute_volume(isa, zol->muted, zol->curvol);
 161 }
 162
 163 /* Get signal strength */
 164 static u32 zoltrix_g_rxsubchans(struct radio_isa_card *isa)
 165 {
 166         struct zoltrix *zol = container_of(isa, struct zoltrix, isa);
 167         int a, b;
 168
 169         outb(0x00, isa->io);         /* This stuff I found to do nothing */
 170         outb(zol->curvol, isa->io);
 171         msleep(20);
 172
 173         a = inb(isa->io);
 174         msleep(10);
 175         b = inb(isa->io);
 176
 177         return (a == b && a == 0xcf) ?
 178                 V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO;
 179 }
 180
 181 static u32 zoltrix_g_signal(struct radio_isa_card *isa)
 182 {
 183         struct zoltrix *zol = container_of(isa, struct zoltrix, isa);
 184         int a, b;
 185
 186         outb(0x00, isa->io);         /* This stuff I found to do nothing */
 187         outb(zol->curvol, isa->io);
 188         msleep(20);
 189
 190         a = inb(isa->io);
 191         msleep(10);
 192         b = inb(isa->io);
 193
 194         if (a != b)
 195                 return 0;
 196
 197         /* I found this out by playing with a binary scanner on the card io */
 198         return (a == 0xcf || a == 0xdf || a == 0xef) ? 0xffff : 0;
 199 }
 200
 201 static int zoltrix_s_stereo(struct radio_isa_card *isa, bool stereo)
 202 {
 203         return zoltrix_s_frequency(isa, isa->freq);
 204 }
 205
 206 static const struct radio_isa_ops zoltrix_ops = {
 207         .alloc = zoltrix_alloc,
 208         .s_mute_volume = zoltrix_s_mute_volume,
 209         .s_frequency = zoltrix_s_frequency,
 210         .s_stereo = zoltrix_s_stereo,
 211         .g_rxsubchans = zoltrix_g_rxsubchans,
 212         .g_signal = zoltrix_g_signal,
 213 };
 214
 215 static const int zoltrix_ioports[] = { 0x20c, 0x30c };
 216
 217 static struct radio_isa_driver zoltrix_driver = {
 218         .driver = {
 219                 .match          = radio_isa_match,
 220                 .probe          = radio_isa_probe,
 221                 .remove         = radio_isa_remove,
 222                 .driver         = {
 223                         .name   = "radio-zoltrix",
 224                 },
 225         },
 226         .io_params = io,
 227         .radio_nr_params = radio_nr,
 228         .io_ports = zoltrix_ioports,
 229         .num_of_io_ports = ARRAY_SIZE(zoltrix_ioports),
 230         .region_size = 2,
 231         .card = "Zoltrix Radio Plus",
 232         .ops = &zoltrix_ops,
 233         .has_stereo = true,
 234         .max_volume = 15,
 235 };
 236
 237 static int __init zoltrix_init(void)
 238 {
 239         return isa_register_driver(&zoltrix_driver.driver, ZOLTRIX_MAX);
 240 }
 241
 242 static void __exit zoltrix_exit(void)
 243 {
 244         isa_unregister_driver(&zoltrix_driver.driver);
 245 }
 246
 247 module_init(zoltrix_init);
 248 module_exit(zoltrix_exit);
 249