pci/cobalt/cobalt-alsa-main.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  *  ALSA interface to cobalt PCM capture streams
0004  *
0005  *  Copyright 2014-2015 Cisco Systems, Inc. and/or its affiliates.
0006  *  All rights reserved.
0007  */
0008
0009 #include <linux/init.h>
0010 #include <linux/slab.h>
0011 #include <linux/module.h>
0012 #include <linux/kernel.h>
0013 #include <linux/device.h>
0014 #include <linux/spinlock.h>
0015
0016 #include <media/v4l2-device.h>
0017
0018 #include <sound/core.h>
0019 #include <sound/initval.h>
0020
0021 #include "cobalt-driver.h"
0022 #include "cobalt-alsa.h"
0023 #include "cobalt-alsa-pcm.h"
0024
0025 static void snd_cobalt_card_free(struct snd_cobalt_card *cobsc)
0026 {
0027     if (cobsc == NULL)
0028         return;
0029
0030     cobsc->s->alsa = NULL;
0031
0032     kfree(cobsc);
0033 }
0034
0035 static void snd_cobalt_card_private_free(struct snd_card *sc)
0036 {
0037     if (sc == NULL)
0038         return;
0039     snd_cobalt_card_free(sc->private_data);
0040     sc->private_data = NULL;
0041     sc->private_free = NULL;
0042 }
0043
0044 static int snd_cobalt_card_create(struct cobalt_stream *s,
0045                        struct snd_card *sc,
0046                        struct snd_cobalt_card **cobsc)
0047 {
0048     *cobsc = kzalloc(sizeof(struct snd_cobalt_card), GFP_KERNEL);
0049     if (*cobsc == NULL)
0050         return -ENOMEM;
0051
0052     (*cobsc)->s = s;
0053     (*cobsc)->sc = sc;
0054
0055     sc->private_data = *cobsc;
0056     sc->private_free = snd_cobalt_card_private_free;
0057
0058     return 0;
0059 }
0060
0061 static int snd_cobalt_card_set_names(struct snd_cobalt_card *cobsc)
0062 {
0063     struct cobalt_stream *s = cobsc->s;
0064     struct cobalt *cobalt = s->cobalt;
0065     struct snd_card *sc = cobsc->sc;
0066
0067     /* sc->driver is used by alsa-lib's configurator: simple, unique */
0068     strscpy(sc->driver, "cobalt", sizeof(sc->driver));
0069
0070     /* sc->shortname is a symlink in /proc/asound: COBALT-M -> cardN */
0071     snprintf(sc->shortname,  sizeof(sc->shortname), "cobalt-%d-%d",
0072          cobalt->instance, s->video_channel);
0073
0074     /* sc->longname is read from /proc/asound/cards */
0075     snprintf(sc->longname, sizeof(sc->longname),
0076          "Cobalt %d HDMI %d",
0077          cobalt->instance, s->video_channel);
0078
0079     return 0;
0080 }
0081
0082 int cobalt_alsa_init(struct cobalt_stream *s)
0083 {
0084     struct cobalt *cobalt = s->cobalt;
0085     struct snd_card *sc = NULL;
0086     struct snd_cobalt_card *cobsc;
0087     int ret;
0088
0089     /* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */
0090
0091     /* (1) Check and increment the device index */
0092     /* This is a no-op for us.  We'll use the cobalt->instance */
0093
0094     /* (2) Create a card instance */
0095     ret = snd_card_new(&cobalt->pci_dev->dev, SNDRV_DEFAULT_IDX1,
0096                SNDRV_DEFAULT_STR1, THIS_MODULE, 0, &sc);
0097     if (ret) {
0098         cobalt_err("snd_card_new() failed with err %d\n", ret);
0099         goto err_exit;
0100     }
0101
0102     /* (3) Create a main component */
0103     ret = snd_cobalt_card_create(s, sc, &cobsc);
0104     if (ret) {
0105         cobalt_err("snd_cobalt_card_create() failed with err %d\n",
0106                ret);
0107         goto err_exit_free;
0108     }
0109
0110     /* (4) Set the driver ID and name strings */
0111     snd_cobalt_card_set_names(cobsc);
0112
0113     ret = snd_cobalt_pcm_create(cobsc);
0114     if (ret) {
0115         cobalt_err("snd_cobalt_pcm_create() failed with err %d\n",
0116                ret);
0117         goto err_exit_free;
0118     }
0119     /* FIXME - proc files */
0120
0121     /* (7) Set the driver data and return 0 */
0122     /* We do this out of normal order for PCI drivers to avoid races */
0123     s->alsa = cobsc;
0124
0125     /* (6) Register the card instance */
0126     ret = snd_card_register(sc);
0127     if (ret) {
0128         s->alsa = NULL;
0129         cobalt_err("snd_card_register() failed with err %d\n", ret);
0130         goto err_exit_free;
0131     }
0132
0133     return 0;
0134
0135 err_exit_free:
0136     if (sc != NULL)
0137         snd_card_free(sc);
0138     kfree(cobsc);
0139 err_exit:
0140     return ret;
0141 }
0142
0143 void cobalt_alsa_exit(struct cobalt_stream *s)
0144 {
0145     struct snd_cobalt_card *cobsc = s->alsa;
0146
0147     if (cobsc)
0148         snd_card_free(cobsc->sc);
0149     s->alsa = NULL;
0150 }