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
  37 int 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
  45 module_param_named(debug, cx18_alsa_debug, int, 0644);
  46 MODULE_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
  51 MODULE_AUTHOR("Andy Walls");
  52 MODULE_DESCRIPTION("CX23418 ALSA Interface");
  53 MODULE_SUPPORTED_DEVICE("CX23418 MPEG2 encoder");
  54 MODULE_LICENSE("GPL");
  55
  56 MODULE_VERSION(CX18_VERSION);
  57
  58 static inline
  59 struct snd_cx18_card *to_snd_cx18_card(struct v4l2_device *v4l2_dev)
  60 {
  61         return to_cx18(v4l2_dev)->alsa;
  62 }
  63
  64 static inline
  65 struct 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
  70 static 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
  83 static 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
  92 static 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
 109 static 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
 129 static 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
 187 err_exit_free:
 188         if (sc != NULL)
 189                 snd_card_free(sc);
 190         kfree(cxsc);
 191 err_exit:
 192         return ret;
 193 }
 194
 195 static 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
 235 static 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
 242 static 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
 252 static 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
 274 static 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
 289 module_init(cx18_alsa_init);
 290 module_exit(cx18_alsa_exit);