LXR linux/drivers/media/pci/cx18/cx18-alsa-main.c

   1/*
   2 *  ALSA interface to cx18 PCM capture streams
   3 *
   4 *  Copyright (C) 2009  Andy Walls <awalls@md.metrocast.net>
   5 *  Copyright (C) 2009  Devin Heitmueller <dheitmueller@kernellabs.com>
   6 *
   7 *  Portions of this work were sponsored by ONELAN Limited.
   8 *
   9 *  This program is free software; you can redistribute it and/or modify
  10 *  it under the terms of the GNU General Public License as published by
  11 *  the Free Software Foundation; either version 2 of the License, or
  12 *  (at your option) any later version.
  13 *
  14 *  This program is distributed in the hope that it will be useful,
  15 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 *  GNU General Public License for more details.
  18 */
  19
  20#include <linux/init.h>
  21#include <linux/slab.h>
  22#include <linux/module.h>
  23#include <linux/kernel.h>
  24#include <linux/device.h>
  25#include <linux/spinlock.h>
  26
  27#include <media/v4l2-device.h>
  28
  29#include <sound/core.h>
  30#include <sound/initval.h>
  31
  32#include "cx18-driver.h"
  33#include "cx18-version.h"
  34#include "cx18-alsa.h"
  35#include "cx18-alsa-pcm.h"
  36
  37int cx18_alsa_debug;
  38
  39#define CX18_DEBUG_ALSA_INFO(fmt, arg...) \
  40        do { \
  41                if (cx18_alsa_debug & 2) \
  42                        printk(KERN_INFO "%s: " fmt, "cx18-alsa", ## arg); \
  43        } while (0);
  44
  45module_param_named(debug, cx18_alsa_debug, int, 0644);
  46MODULE_PARM_DESC(debug,
  47                 "Debug level (bitmask). Default: 0\n"
  48                 "\t\t\t  1/0x0001: warning\n"
  49                 "\t\t\t  2/0x0002: info\n");
  50
  51MODULE_AUTHOR("Andy Walls");
  52MODULE_DESCRIPTION("CX23418 ALSA Interface");
  53MODULE_SUPPORTED_DEVICE("CX23418 MPEG2 encoder");
  54MODULE_LICENSE("GPL");
  55
  56MODULE_VERSION(CX18_VERSION);
  57
  58static inline
  59struct snd_cx18_card *to_snd_cx18_card(struct v4l2_device *v4l2_dev)
  60{
  61        return to_cx18(v4l2_dev)->alsa;
  62}
  63
  64static inline
  65struct snd_cx18_card *p_to_snd_cx18_card(struct v4l2_device **v4l2_dev)
  66{
  67        return container_of(v4l2_dev, struct snd_cx18_card, v4l2_dev);
  68}
  69
  70static void snd_cx18_card_free(struct snd_cx18_card *cxsc)
  71{
  72        if (cxsc == NULL)
  73                return;
  74
  75        if (cxsc->v4l2_dev != NULL)
  76                to_cx18(cxsc->v4l2_dev)->alsa = NULL;
  77
  78        /* FIXME - take any other stopping actions needed */
  79
  80        kfree(cxsc);
  81}
  82
  83static void snd_cx18_card_private_free(struct snd_card *sc)
  84{
  85        if (sc == NULL)
  86                return;
  87        snd_cx18_card_free(sc->private_data);
  88        sc->private_data = NULL;
  89        sc->private_free = NULL;
  90}
  91
  92static int snd_cx18_card_create(struct v4l2_device *v4l2_dev,
  93                                       struct snd_card *sc,
  94                                       struct snd_cx18_card **cxsc)
  95{
  96        *cxsc = kzalloc(sizeof(struct snd_cx18_card), GFP_KERNEL);
  97        if (*cxsc == NULL)
  98                return -ENOMEM;
  99
 100        (*cxsc)->v4l2_dev = v4l2_dev;
 101        (*cxsc)->sc = sc;
 102
 103        sc->private_data = *cxsc;
 104        sc->private_free = snd_cx18_card_private_free;
 105
 106        return 0;
 107}
 108
 109static int snd_cx18_card_set_names(struct snd_cx18_card *cxsc)
 110{
 111        struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
 112        struct snd_card *sc = cxsc->sc;
 113
 114        /* sc->driver is used by alsa-lib's configurator: simple, unique */
 115        strlcpy(sc->driver, "CX23418", sizeof(sc->driver));
 116
 117        /* sc->shortname is a symlink in /proc/asound: CX18-M -> cardN */
 118        snprintf(sc->shortname,  sizeof(sc->shortname), "CX18-%d",
 119                 cx->instance);
 120
 121        /* sc->longname is read from /proc/asound/cards */
 122        snprintf(sc->longname, sizeof(sc->longname),
 123                 "CX23418 #%d %s TV/FM Radio/Line-In Capture",
 124                 cx->instance, cx->card_name);
 125
 126        return 0;
 127}
 128
 129static int snd_cx18_init(struct v4l2_device *v4l2_dev)
 130{
 131        struct cx18 *cx = to_cx18(v4l2_dev);
 132        struct snd_card *sc = NULL;
 133        struct snd_cx18_card *cxsc;
 134        int ret;
 135
 136        /* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */
 137
 138        /* (1) Check and increment the device index */
 139        /* This is a no-op for us.  We'll use the cx->instance */
 140
 141        /* (2) Create a card instance */
 142        ret = snd_card_new(&cx->pci_dev->dev,
 143                           SNDRV_DEFAULT_IDX1, /* use first available id */
 144                           SNDRV_DEFAULT_STR1, /* xid from end of shortname*/
 145                           THIS_MODULE, 0, &sc);
 146        if (ret) {
 147                CX18_ALSA_ERR("%s: snd_card_new() failed with err %d\n",
 148                              __func__, ret);
 149                goto err_exit;
 150        }
 151
 152        /* (3) Create a main component */
 153        ret = snd_cx18_card_create(v4l2_dev, sc, &cxsc);
 154        if (ret) {
 155                CX18_ALSA_ERR("%s: snd_cx18_card_create() failed with err %d\n",
 156                              __func__, ret);
 157                goto err_exit_free;
 158        }
 159
 160        /* (4) Set the driver ID and name strings */
 161        snd_cx18_card_set_names(cxsc);
 162
 163
 164        ret = snd_cx18_pcm_create(cxsc);
 165        if (ret) {
 166                CX18_ALSA_ERR("%s: snd_cx18_pcm_create() failed with err %d\n",
 167                              __func__, ret);
 168                goto err_exit_free;
 169        }
 170        /* FIXME - proc files */
 171
 172        /* (7) Set the driver data and return 0 */
 173        /* We do this out of normal order for PCI drivers to avoid races */
 174        cx->alsa = cxsc;
 175
 176        /* (6) Register the card instance */
 177        ret = snd_card_register(sc);
 178        if (ret) {
 179                cx->alsa = NULL;
 180                CX18_ALSA_ERR("%s: snd_card_register() failed with err %d\n",
 181                              __func__, ret);
 182                goto err_exit_free;
 183        }
 184
 185        return 0;
 186
 187err_exit_free:
 188        if (sc != NULL)
 189                snd_card_free(sc);
 190        kfree(cxsc);
 191err_exit:
 192        return ret;
 193}
 194
 195static int cx18_alsa_load(struct cx18 *cx)
 196{
 197        struct v4l2_device *v4l2_dev = &cx->v4l2_dev;
 198        struct cx18_stream *s;
 199
 200        if (v4l2_dev == NULL) {
 201                printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
 202                       __func__);
 203                return 0;
 204        }
 205
 206        cx = to_cx18(v4l2_dev);
 207        if (cx == NULL) {
 208                printk(KERN_ERR "cx18-alsa cx is NULL\n");
 209                return 0;
 210        }
 211
 212        s = &cx->streams[CX18_ENC_STREAM_TYPE_PCM];
 213        if (s->video_dev.v4l2_dev == NULL) {
 214                CX18_DEBUG_ALSA_INFO("%s: PCM stream for card is disabled - skipping\n",
 215                                     __func__);
 216                return 0;
 217        }
 218
 219        if (cx->alsa != NULL) {
 220                CX18_ALSA_ERR("%s: struct snd_cx18_card * already exists\n",
 221                              __func__);
 222                return 0;
 223        }
 224
 225        if (snd_cx18_init(v4l2_dev)) {
 226                CX18_ALSA_ERR("%s: failed to create struct snd_cx18_card\n",
 227                              __func__);
 228        } else {
 229                CX18_DEBUG_ALSA_INFO("%s: created cx18 ALSA interface instance\n",
 230                                     __func__);
 231        }
 232        return 0;
 233}
 234
 235static int __init cx18_alsa_init(void)
 236{
 237        printk(KERN_INFO "cx18-alsa: module loading...\n");
 238        cx18_ext_init = &cx18_alsa_load;
 239        return 0;
 240}
 241
 242static void __exit snd_cx18_exit(struct snd_cx18_card *cxsc)
 243{
 244        struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
 245
 246        /* FIXME - pointer checks & shutdown cxsc */
 247
 248        snd_card_free(cxsc->sc);
 249        cx->alsa = NULL;
 250}
 251
 252static int __exit cx18_alsa_exit_callback(struct device *dev, void *data)
 253{
 254        struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
 255        struct snd_cx18_card *cxsc;
 256
 257        if (v4l2_dev == NULL) {
 258                printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
 259                       __func__);
 260                return 0;
 261        }
 262
 263        cxsc = to_snd_cx18_card(v4l2_dev);
 264        if (cxsc == NULL) {
 265                CX18_ALSA_WARN("%s: struct snd_cx18_card * is NULL\n",
 266                               __func__);
 267                return 0;
 268        }
 269
 270        snd_cx18_exit(cxsc);
 271        return 0;
 272}
 273
 274static void __exit cx18_alsa_exit(void)
 275{
 276        struct device_driver *drv;
 277        int ret;
 278
 279        printk(KERN_INFO "cx18-alsa: module unloading...\n");
 280
 281        drv = driver_find("cx18", &pci_bus_type);
 282        ret = driver_for_each_device(drv, NULL, NULL, cx18_alsa_exit_callback);
 283        (void)ret;      /* suppress compiler warning */
 284
 285        cx18_ext_init = NULL;
 286        printk(KERN_INFO "cx18-alsa: module unload complete\n");
 287}
 288
 289module_init(cx18_alsa_init);
 290module_exit(cx18_alsa_exit);
 291