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 
25 static 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(cobsc);
33 }
34 
35 static void snd_cobalt_card_private_free(struct snd_card *sc)
36 {
37 	if (sc == NULL)
38 		return;
39 	snd_cobalt_card_free(sc->private_data);
40 	sc->private_data = NULL;
41 	sc->private_free = NULL;
42 }
43 
44 static int snd_cobalt_card_create(struct cobalt_stream *s,
45 				       struct snd_card *sc,
46 				       struct snd_cobalt_card **cobsc)
47 {
48 	*cobsc = kzalloc(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 
61 static 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(sc->shortname,  sizeof(sc->shortname), "cobalt-%d-%d",
72 		 cobalt->instance, s->video_channel);
73 
74 	/* sc->longname is read from /proc/asound/cards */
75 	snprintf(sc->longname, sizeof(sc->longname),
76 		 "Cobalt %d HDMI %d",
77 		 cobalt->instance, s->video_channel);
78 
79 	return 0;
80 }
81 
82 int 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(&cobalt->pci_dev->dev, SNDRV_DEFAULT_IDX1,
96 			   SNDRV_DEFAULT_STR1, THIS_MODULE, 0, &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);
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(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 
135 err_exit_free:
136 	if (sc != NULL)
137 		snd_card_free(sc);
138 	kfree(cobsc);
139 err_exit:
140 	return ret;
141 }
142 
143 void cobalt_alsa_exit(struct cobalt_stream *s)
144 {
145 	struct snd_cobalt_card *cobsc = s->alsa;
146 
147 	if (cobsc)
148 		snd_card_free(cobsc->sc);
149 	s->alsa = NULL;
150 }
151