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