1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * ALSA interface to cobalt PCM capture streams
4 *
5 * Copyright 2014-2015 Cisco Systems, Inc. and/or its affiliates.
6 * All rights reserved.
7 */
8
9#include <linux/init.h>
10#include <linux/slab.h>
11#include <linux/module.h>
12#include <linux/kernel.h>
13#include <linux/device.h>
14#include <linux/spinlock.h>
15
16#include <media/v4l2-device.h>
17
18#include <sound/core.h>
19#include <sound/initval.h>
20
21#include "cobalt-driver.h"
22#include "cobalt-alsa.h"
23#include "cobalt-alsa-pcm.h"
24
25static void snd_cobalt_card_free(struct snd_cobalt_card *cobsc)
26{
27 if (cobsc == NULL)
28 return;
29
30 cobsc->s->alsa = NULL;
31
32 kfree(objp: cobsc);
33}
34
35static void snd_cobalt_card_private_free(struct snd_card *sc)
36{
37 if (sc == NULL)
38 return;
39 snd_cobalt_card_free(cobsc: sc->private_data);
40 sc->private_data = NULL;
41 sc->private_free = NULL;
42}
43
44static int snd_cobalt_card_create(struct cobalt_stream *s,
45 struct snd_card *sc,
46 struct snd_cobalt_card **cobsc)
47{
48 *cobsc = kzalloc(size: sizeof(struct snd_cobalt_card), GFP_KERNEL);
49 if (*cobsc == NULL)
50 return -ENOMEM;
51
52 (*cobsc)->s = s;
53 (*cobsc)->sc = sc;
54
55 sc->private_data = *cobsc;
56 sc->private_free = snd_cobalt_card_private_free;
57
58 return 0;
59}
60
61static int snd_cobalt_card_set_names(struct snd_cobalt_card *cobsc)
62{
63 struct cobalt_stream *s = cobsc->s;
64 struct cobalt *cobalt = s->cobalt;
65 struct snd_card *sc = cobsc->sc;
66
67 /* sc->driver is used by alsa-lib's configurator: simple, unique */
68 strscpy(sc->driver, "cobalt", sizeof(sc->driver));
69
70 /* sc->shortname is a symlink in /proc/asound: COBALT-M -> cardN */
71 snprintf(buf: sc->shortname, size: sizeof(sc->shortname), fmt: "cobalt-%d-%d",
72 cobalt->instance, s->video_channel);
73
74 /* sc->longname is read from /proc/asound/cards */
75 snprintf(buf: sc->longname, size: sizeof(sc->longname),
76 fmt: "Cobalt %d HDMI %d",
77 cobalt->instance, s->video_channel);
78
79 return 0;
80}
81
82int cobalt_alsa_init(struct cobalt_stream *s)
83{
84 struct cobalt *cobalt = s->cobalt;
85 struct snd_card *sc = NULL;
86 struct snd_cobalt_card *cobsc;
87 int ret;
88
89 /* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */
90
91 /* (1) Check and increment the device index */
92 /* This is a no-op for us. We'll use the cobalt->instance */
93
94 /* (2) Create a card instance */
95 ret = snd_card_new(parent: &cobalt->pci_dev->dev, SNDRV_DEFAULT_IDX1,
96 SNDRV_DEFAULT_STR1, THIS_MODULE, extra_size: 0, card_ret: &sc);
97 if (ret) {
98 cobalt_err("snd_card_new() failed with err %d\n", ret);
99 goto err_exit;
100 }
101
102 /* (3) Create a main component */
103 ret = snd_cobalt_card_create(s, sc, cobsc: &cobsc);
104 if (ret) {
105 cobalt_err("snd_cobalt_card_create() failed with err %d\n",
106 ret);
107 goto err_exit_free;
108 }
109
110 /* (4) Set the driver ID and name strings */
111 snd_cobalt_card_set_names(cobsc);
112
113 ret = snd_cobalt_pcm_create(cobsc);
114 if (ret) {
115 cobalt_err("snd_cobalt_pcm_create() failed with err %d\n",
116 ret);
117 goto err_exit_free;
118 }
119 /* FIXME - proc files */
120
121 /* (7) Set the driver data and return 0 */
122 /* We do this out of normal order for PCI drivers to avoid races */
123 s->alsa = cobsc;
124
125 /* (6) Register the card instance */
126 ret = snd_card_register(card: sc);
127 if (ret) {
128 s->alsa = NULL;
129 cobalt_err("snd_card_register() failed with err %d\n", ret);
130 goto err_exit_free;
131 }
132
133 return 0;
134
135err_exit_free:
136 if (sc != NULL)
137 snd_card_free(card: sc);
138 kfree(objp: cobsc);
139err_exit:
140 return ret;
141}
142
143void cobalt_alsa_exit(struct cobalt_stream *s)
144{
145 struct snd_cobalt_card *cobsc = s->alsa;
146
147 if (cobsc)
148 snd_card_free(card: cobsc->sc);
149 s->alsa = NULL;
150}
151

source code of linux/drivers/media/pci/cobalt/cobalt-alsa-main.c