drivers/media/pci/cobalt/cobalt-alsa-main.c

   1 /*
   2  *  ALSA interface to cobalt PCM capture streams
   3  *
   4  *  Copyright 2014-2015 Cisco Systems, Inc. and/or its affiliates.
   5  *  All rights reserved.
   6  *
   7  *  This program is free software; you may redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; version 2 of the License.
  10  *
  11  *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  12  *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  13  *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  14  *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  15  *  BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  16  *  ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  17  *  CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  18  *  SOFTWARE.
  19  */
  20
  21 #include <linux/init.h>
  22 #include <linux/slab.h>
  23 #include <linux/module.h>
  24 #include <linux/kernel.h>
  25 #include <linux/device.h>
  26 #include <linux/spinlock.h>
  27
  28 #include <media/v4l2-device.h>
  29
  30 #include <sound/core.h>
  31 #include <sound/initval.h>
  32
  33 #include "cobalt-driver.h"
  34 #include "cobalt-alsa.h"
  35 #include "cobalt-alsa-pcm.h"
  36
  37 static void snd_cobalt_card_free(struct snd_cobalt_card *cobsc)
  38 {
  39         if (cobsc == NULL)
  40                 return;
  41
  42         cobsc->s->alsa = NULL;
  43
  44         kfree(cobsc);
  45 }
  46
  47 static void snd_cobalt_card_private_free(struct snd_card *sc)
  48 {
  49         if (sc == NULL)
  50                 return;
  51         snd_cobalt_card_free(sc->private_data);
  52         sc->private_data = NULL;
  53         sc->private_free = NULL;
  54 }
  55
  56 static int snd_cobalt_card_create(struct cobalt_stream *s,
  57                                        struct snd_card *sc,
  58                                        struct snd_cobalt_card **cobsc)
  59 {
  60         *cobsc = kzalloc(sizeof(struct snd_cobalt_card), GFP_KERNEL);
  61         if (*cobsc == NULL)
  62                 return -ENOMEM;
  63
  64         (*cobsc)->s = s;
  65         (*cobsc)->sc = sc;
  66
  67         sc->private_data = *cobsc;
  68         sc->private_free = snd_cobalt_card_private_free;
  69
  70         return 0;
  71 }
  72
  73 static int snd_cobalt_card_set_names(struct snd_cobalt_card *cobsc)
  74 {
  75         struct cobalt_stream *s = cobsc->s;
  76         struct cobalt *cobalt = s->cobalt;
  77         struct snd_card *sc = cobsc->sc;
  78
  79         /* sc->driver is used by alsa-lib's configurator: simple, unique */
  80         strlcpy(sc->driver, "cobalt", sizeof(sc->driver));
  81
  82         /* sc->shortname is a symlink in /proc/asound: COBALT-M -> cardN */
  83         snprintf(sc->shortname,  sizeof(sc->shortname), "cobalt-%d-%d",
  84                  cobalt->instance, s->video_channel);
  85
  86         /* sc->longname is read from /proc/asound/cards */
  87         snprintf(sc->longname, sizeof(sc->longname),
  88                  "Cobalt %d HDMI %d",
  89                  cobalt->instance, s->video_channel);
  90
  91         return 0;
  92 }
  93
  94 int cobalt_alsa_init(struct cobalt_stream *s)
  95 {
  96         struct cobalt *cobalt = s->cobalt;
  97         struct snd_card *sc = NULL;
  98         struct snd_cobalt_card *cobsc;
  99         int ret;
 100
 101         /* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */
 102
 103         /* (1) Check and increment the device index */
 104         /* This is a no-op for us.  We'll use the cobalt->instance */
 105
 106         /* (2) Create a card instance */
 107         ret = snd_card_new(&cobalt->pci_dev->dev, SNDRV_DEFAULT_IDX1,
 108                            SNDRV_DEFAULT_STR1, THIS_MODULE, 0, &sc);
 109         if (ret) {
 110                 cobalt_err("snd_card_new() failed with err %d\n", ret);
 111                 goto err_exit;
 112         }
 113
 114         /* (3) Create a main component */
 115         ret = snd_cobalt_card_create(s, sc, &cobsc);
 116         if (ret) {
 117                 cobalt_err("snd_cobalt_card_create() failed with err %d\n",
 118                            ret);
 119                 goto err_exit_free;
 120         }
 121
 122         /* (4) Set the driver ID and name strings */
 123         snd_cobalt_card_set_names(cobsc);
 124
 125         ret = snd_cobalt_pcm_create(cobsc);
 126         if (ret) {
 127                 cobalt_err("snd_cobalt_pcm_create() failed with err %d\n",
 128                            ret);
 129                 goto err_exit_free;
 130         }
 131         /* FIXME - proc files */
 132
 133         /* (7) Set the driver data and return 0 */
 134         /* We do this out of normal order for PCI drivers to avoid races */
 135         s->alsa = cobsc;
 136
 137         /* (6) Register the card instance */
 138         ret = snd_card_register(sc);
 139         if (ret) {
 140                 s->alsa = NULL;
 141                 cobalt_err("snd_card_register() failed with err %d\n", ret);
 142                 goto err_exit_free;
 143         }
 144
 145         return 0;
 146
 147 err_exit_free:
 148         if (sc != NULL)
 149                 snd_card_free(sc);
 150         kfree(cobsc);
 151 err_exit:
 152         return ret;
 153 }
 154
 155 void cobalt_alsa_exit(struct cobalt_stream *s)
 156 {
 157         struct snd_cobalt_card *cobsc = s->alsa;
 158
 159         if (cobsc)
 160                 snd_card_free(cobsc->sc);
 161         s->alsa = NULL;
 162 }