2 * ALSA interface to cx18 PCM capture streams
4 * Copyright (C) 2009 Andy Walls <awalls@md.metrocast.net>
5 * Copyright (C) 2009 Devin Heitmueller <dheitmueller@kernellabs.com>
7 * Portions of this work were sponsored by ONELAN Limited.
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
25 #include <linux/init.h>
26 #include <linux/slab.h>
27 #include <linux/module.h>
28 #include <linux/kernel.h>
29 #include <linux/device.h>
30 #include <linux/spinlock.h>
32 #include <media/v4l2-device.h>
34 #include <sound/core.h>
35 #include <sound/initval.h>
37 #include "cx18-driver.h"
38 #include "cx18-version.h"
39 #include "cx18-alsa.h"
40 #include "cx18-alsa-mixer.h"
41 #include "cx18-alsa-pcm.h"
45 #define CX18_DEBUG_ALSA_INFO(fmt, arg...) \
47 if (cx18_alsa_debug & 2) \
48 printk(KERN_INFO "%s: " fmt, "cx18-alsa", ## arg); \
51 module_param_named(debug, cx18_alsa_debug, int, 0644);
52 MODULE_PARM_DESC(debug,
53 "Debug level (bitmask). Default: 0\n"
54 "\t\t\t 1/0x0001: warning\n"
55 "\t\t\t 2/0x0002: info\n");
57 MODULE_AUTHOR("Andy Walls");
58 MODULE_DESCRIPTION("CX23418 ALSA Interface");
59 MODULE_SUPPORTED_DEVICE("CX23418 MPEG2 encoder");
60 MODULE_LICENSE("GPL");
62 MODULE_VERSION(CX18_VERSION);
65 struct snd_cx18_card *to_snd_cx18_card(struct v4l2_device *v4l2_dev)
67 return to_cx18(v4l2_dev)->alsa;
71 struct snd_cx18_card *p_to_snd_cx18_card(struct v4l2_device **v4l2_dev)
73 return container_of(v4l2_dev, struct snd_cx18_card, v4l2_dev);
76 static void snd_cx18_card_free(struct snd_cx18_card *cxsc)
81 if (cxsc->v4l2_dev != NULL)
82 to_cx18(cxsc->v4l2_dev)->alsa = NULL;
84 /* FIXME - take any other stopping actions needed */
89 static void snd_cx18_card_private_free(struct snd_card *sc)
93 snd_cx18_card_free(sc->private_data);
94 sc->private_data = NULL;
95 sc->private_free = NULL;
98 static int snd_cx18_card_create(struct v4l2_device *v4l2_dev,
100 struct snd_cx18_card **cxsc)
102 *cxsc = kzalloc(sizeof(struct snd_cx18_card), GFP_KERNEL);
106 (*cxsc)->v4l2_dev = v4l2_dev;
109 sc->private_data = *cxsc;
110 sc->private_free = snd_cx18_card_private_free;
115 static int snd_cx18_card_set_names(struct snd_cx18_card *cxsc)
117 struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
118 struct snd_card *sc = cxsc->sc;
120 /* sc->driver is used by alsa-lib's configurator: simple, unique */
121 strlcpy(sc->driver, "CX23418", sizeof(sc->driver));
123 /* sc->shortname is a symlink in /proc/asound: CX18-M -> cardN */
124 snprintf(sc->shortname, sizeof(sc->shortname), "CX18-%d",
127 /* sc->longname is read from /proc/asound/cards */
128 snprintf(sc->longname, sizeof(sc->longname),
129 "CX23418 #%d %s TV/FM Radio/Line-In Capture",
130 cx->instance, cx->card_name);
135 static int snd_cx18_init(struct v4l2_device *v4l2_dev)
137 struct cx18 *cx = to_cx18(v4l2_dev);
138 struct snd_card *sc = NULL;
139 struct snd_cx18_card *cxsc;
142 /* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */
144 /* (1) Check and increment the device index */
145 /* This is a no-op for us. We'll use the cx->instance */
147 /* (2) Create a card instance */
148 ret = snd_card_new(&cx->pci_dev->dev,
149 SNDRV_DEFAULT_IDX1, /* use first available id */
150 SNDRV_DEFAULT_STR1, /* xid from end of shortname*/
151 THIS_MODULE, 0, &sc);
153 CX18_ALSA_ERR("%s: snd_card_new() failed with err %d\n",
158 /* (3) Create a main component */
159 ret = snd_cx18_card_create(v4l2_dev, sc, &cxsc);
161 CX18_ALSA_ERR("%s: snd_cx18_card_create() failed with err %d\n",
166 /* (4) Set the driver ID and name strings */
167 snd_cx18_card_set_names(cxsc);
170 ret = snd_cx18_pcm_create(cxsc);
172 CX18_ALSA_ERR("%s: snd_cx18_pcm_create() failed with err %d\n",
176 /* FIXME - proc files */
178 /* (7) Set the driver data and return 0 */
179 /* We do this out of normal order for PCI drivers to avoid races */
182 /* (6) Register the card instance */
183 ret = snd_card_register(sc);
186 CX18_ALSA_ERR("%s: snd_card_register() failed with err %d\n",
201 static int cx18_alsa_load(struct cx18 *cx)
203 struct v4l2_device *v4l2_dev = &cx->v4l2_dev;
204 struct cx18_stream *s;
206 if (v4l2_dev == NULL) {
207 printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
212 cx = to_cx18(v4l2_dev);
214 printk(KERN_ERR "cx18-alsa cx is NULL\n");
218 s = &cx->streams[CX18_ENC_STREAM_TYPE_PCM];
219 if (s->video_dev.v4l2_dev == NULL) {
220 CX18_DEBUG_ALSA_INFO("%s: PCM stream for card is disabled - "
221 "skipping\n", __func__);
225 if (cx->alsa != NULL) {
226 CX18_ALSA_ERR("%s: struct snd_cx18_card * already exists\n",
231 if (snd_cx18_init(v4l2_dev)) {
232 CX18_ALSA_ERR("%s: failed to create struct snd_cx18_card\n",
235 CX18_DEBUG_ALSA_INFO("%s: created cx18 ALSA interface instance "
241 static int __init cx18_alsa_init(void)
243 printk(KERN_INFO "cx18-alsa: module loading...\n");
244 cx18_ext_init = &cx18_alsa_load;
248 static void __exit snd_cx18_exit(struct snd_cx18_card *cxsc)
250 struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
252 /* FIXME - pointer checks & shutdown cxsc */
254 snd_card_free(cxsc->sc);
258 static int __exit cx18_alsa_exit_callback(struct device *dev, void *data)
260 struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
261 struct snd_cx18_card *cxsc;
263 if (v4l2_dev == NULL) {
264 printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
269 cxsc = to_snd_cx18_card(v4l2_dev);
271 CX18_ALSA_WARN("%s: struct snd_cx18_card * is NULL\n",
280 static void __exit cx18_alsa_exit(void)
282 struct device_driver *drv;
285 printk(KERN_INFO "cx18-alsa: module unloading...\n");
287 drv = driver_find("cx18", &pci_bus_type);
288 ret = driver_for_each_device(drv, NULL, NULL, cx18_alsa_exit_callback);
289 (void)ret; /* suppress compiler warning */
291 cx18_ext_init = NULL;
292 printk(KERN_INFO "cx18-alsa: module unload complete\n");
295 module_init(cx18_alsa_init);
296 module_exit(cx18_alsa_exit);