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 }
163