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 *  You should have received a copy of the GNU General Public License
  20 *  along with this program; if not, write to the Free Software
  21 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  22 *  02111-1307  USA
  23 */
  24
  25#include <linux/init.h>
  26#include <linux/slab.h>
  27#include <linux/module.h>
  28#include <linux/kernel.h>
  29#include <linux/device.h>
  30#include <linux/spinlock.h>
  31
  32#include <media/v4l2-device.h>
  33
  34#include <sound/core.h>
  35#include <sound/initval.h>
  36
  37#include "cx18-driver.h"
  38#include "cx18-version.h"
  39#include "cx18-alsa.h"
  40#include "cx18-alsa-mixer.h"
  41#include "cx18-alsa-pcm.h"
  42
  43int cx18_alsa_debug;
  44
  45#define CX18_DEBUG_ALSA_INFO(fmt, arg...) \
  46        do { \
  47                if (cx18_alsa_debug & 2) \
  48                        printk(KERN_INFO "%s: " fmt, "cx18-alsa", ## arg); \
  49        } while (0);
  50
  51module_param_named(debug, cx18_alsa_debug, int, 0644);
  52MODULE_PARM_DESC(debug,
  53                 "Debug level (bitmask). Default: 0\n"
  54                 "\t\t\t  1/0x0001: warning\n"
  55                 "\t\t\t  2/0x0002: info\n");
  56
  57MODULE_AUTHOR("Andy Walls");
  58MODULE_DESCRIPTION("CX23418 ALSA Interface");
  59MODULE_SUPPORTED_DEVICE("CX23418 MPEG2 encoder");
  60MODULE_LICENSE("GPL");
  61
  62MODULE_VERSION(CX18_VERSION);
  63
  64static inline
  65struct snd_cx18_card *to_snd_cx18_card(struct v4l2_device *v4l2_dev)
  66{
  67        return to_cx18(v4l2_dev)->alsa;
  68}
  69
  70static inline
  71struct snd_cx18_card *p_to_snd_cx18_card(struct v4l2_device **v4l2_dev)
  72{
  73        return container_of(v4l2_dev, struct snd_cx18_card, v4l2_dev);
  74}
  75
  76static void snd_cx18_card_free(struct snd_cx18_card *cxsc)
  77{
  78        if (cxsc == NULL)
  79                return;
  80
  81        if (cxsc->v4l2_dev != NULL)
  82                to_cx18(cxsc->v4l2_dev)->alsa = NULL;
  83
  84        /* FIXME - take any other stopping actions needed */
  85
  86        kfree(cxsc);
  87}
  88
  89static void snd_cx18_card_private_free(struct snd_card *sc)
  90{
  91        if (sc == NULL)
  92                return;
  93        snd_cx18_card_free(sc->private_data);
  94        sc->private_data = NULL;
  95        sc->private_free = NULL;
  96}
  97
  98static int snd_cx18_card_create(struct v4l2_device *v4l2_dev,
  99                                       struct snd_card *sc,
 100                                       struct snd_cx18_card **cxsc)
 101{
 102        *cxsc = kzalloc(sizeof(struct snd_cx18_card), GFP_KERNEL);
 103        if (*cxsc == NULL)
 104                return -ENOMEM;
 105
 106        (*cxsc)->v4l2_dev = v4l2_dev;
 107        (*cxsc)->sc = sc;
 108
 109        sc->private_data = *cxsc;
 110        sc->private_free = snd_cx18_card_private_free;
 111
 112        return 0;
 113}
 114
 115static int snd_cx18_card_set_names(struct snd_cx18_card *cxsc)
 116{
 117        struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
 118        struct snd_card *sc = cxsc->sc;
 119
 120        /* sc->driver is used by alsa-lib's configurator: simple, unique */
 121        strlcpy(sc->driver, "CX23418", sizeof(sc->driver));
 122
 123        /* sc->shortname is a symlink in /proc/asound: CX18-M -> cardN */
 124        snprintf(sc->shortname,  sizeof(sc->shortname), "CX18-%d",
 125                 cx->instance);
 126
 127        /* sc->longname is read from /proc/asound/cards */
 128        snprintf(sc->longname, sizeof(sc->longname),
 129                 "CX23418 #%d %s TV/FM Radio/Line-In Capture",
 130                 cx->instance, cx->card_name);
 131
 132        return 0;
 133}
 134
 135static int snd_cx18_init(struct v4l2_device *v4l2_dev)
 136{
 137        struct cx18 *cx = to_cx18(v4l2_dev);
 138        struct snd_card *sc = NULL;
 139        struct snd_cx18_card *cxsc;
 140        int ret;
 141
 142        /* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */
 143
 144        /* (1) Check and increment the device index */
 145        /* This is a no-op for us.  We'll use the cx->instance */
 146
 147        /* (2) Create a card instance */
 148        ret = snd_card_create(SNDRV_DEFAULT_IDX1, /* use first available id */
 149                              SNDRV_DEFAULT_STR1, /* xid from end of shortname*/
 150                              THIS_MODULE, 0, &sc);
 151        if (ret) {
 152                CX18_ALSA_ERR("%s: snd_card_create() failed with err %d\n",
 153                              __func__, ret);
 154                goto err_exit;
 155        }
 156
 157        /* (3) Create a main component */
 158        ret = snd_cx18_card_create(v4l2_dev, sc, &cxsc);
 159        if (ret) {
 160                CX18_ALSA_ERR("%s: snd_cx18_card_create() failed with err %d\n",
 161                              __func__, ret);
 162                goto err_exit_free;
 163        }
 164
 165        /* (4) Set the driver ID and name strings */
 166        snd_cx18_card_set_names(cxsc);
 167
 168
 169        ret = snd_cx18_pcm_create(cxsc);
 170        if (ret) {
 171                CX18_ALSA_ERR("%s: snd_cx18_pcm_create() failed with err %d\n",
 172                              __func__, ret);
 173                goto err_exit_free;
 174        }
 175        /* FIXME - proc files */
 176
 177        /* (7) Set the driver data and return 0 */
 178        /* We do this out of normal order for PCI drivers to avoid races */
 179        cx->alsa = cxsc;
 180
 181        /* (6) Register the card instance */
 182        ret = snd_card_register(sc);
 183        if (ret) {
 184                cx->alsa = NULL;
 185                CX18_ALSA_ERR("%s: snd_card_register() failed with err %d\n",
 186                              __func__, ret);
 187                goto err_exit_free;
 188        }
 189
 190        return 0;
 191
 192err_exit_free:
 193        if (sc != NULL)
 194                snd_card_free(sc);
 195        kfree(cxsc);
 196err_exit:
 197        return ret;
 198}
 199
 200static int cx18_alsa_load(struct cx18 *cx)
 201{
 202        struct v4l2_device *v4l2_dev = &cx->v4l2_dev;
 203        struct cx18_stream *s;
 204
 205        if (v4l2_dev == NULL) {
 206                printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
 207                       __func__);
 208                return 0;
 209        }
 210
 211        cx = to_cx18(v4l2_dev);
 212        if (cx == NULL) {
 213                printk(KERN_ERR "cx18-alsa cx is NULL\n");
 214                return 0;
 215        }
 216
 217        s = &cx->streams[CX18_ENC_STREAM_TYPE_PCM];
 218        if (s->video_dev == NULL) {
 219                CX18_DEBUG_ALSA_INFO("%s: PCM stream for card is disabled - "
 220                                     "skipping\n", __func__);
 221                return 0;
 222        }
 223
 224        if (cx->alsa != NULL) {
 225                CX18_ALSA_ERR("%s: struct snd_cx18_card * already exists\n",
 226                              __func__);
 227                return 0;
 228        }
 229
 230        if (snd_cx18_init(v4l2_dev)) {
 231                CX18_ALSA_ERR("%s: failed to create struct snd_cx18_card\n",
 232                              __func__);
 233        } else {
 234                CX18_DEBUG_ALSA_INFO("%s: created cx18 ALSA interface instance "
 235                                     "\n", __func__);
 236        }
 237        return 0;
 238}
 239
 240static int __init cx18_alsa_init(void)
 241{
 242        printk(KERN_INFO "cx18-alsa: module loading...\n");
 243        cx18_ext_init = &cx18_alsa_load;
 244        return 0;
 245}
 246
 247static void __exit snd_cx18_exit(struct snd_cx18_card *cxsc)
 248{
 249        struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
 250
 251        /* FIXME - pointer checks & shutdown cxsc */
 252
 253        snd_card_free(cxsc->sc);
 254        cx->alsa = NULL;
 255}
 256
 257static int __exit cx18_alsa_exit_callback(struct device *dev, void *data)
 258{
 259        struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
 260        struct snd_cx18_card *cxsc;
 261
 262        if (v4l2_dev == NULL) {
 263                printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
 264                       __func__);
 265                return 0;
 266        }
 267
 268        cxsc = to_snd_cx18_card(v4l2_dev);
 269        if (cxsc == NULL) {
 270                CX18_ALSA_WARN("%s: struct snd_cx18_card * is NULL\n",
 271                               __func__);
 272                return 0;
 273        }
 274
 275        snd_cx18_exit(cxsc);
 276        return 0;
 277}
 278
 279static void __exit cx18_alsa_exit(void)
 280{
 281        struct device_driver *drv;
 282        int ret;
 283
 284        printk(KERN_INFO "cx18-alsa: module unloading...\n");
 285
 286        drv = driver_find("cx18", &pci_bus_type);
 287        ret = driver_for_each_device(drv, NULL, NULL, cx18_alsa_exit_callback);
 288        (void)ret;      /* suppress compiler warning */
 289
 290        cx18_ext_init = NULL;
 291        printk(KERN_INFO "cx18-alsa: module unload complete\n");
 292}
 293
 294module_init(cx18_alsa_init);
 295module_exit(cx18_alsa_exit);
 296