1 /*
2 * ALSA interface to cx18 PCM capture streams
3 *
4 * Copyright (C) 2009 Andy Walls <awalls@md.metrocast.net>
5 * Copyright (C) 2009 Devin Heitmueller <dheitmueller@kernellabs.com>
6 *
7 * Portions of this work were sponsored by ONELAN Limited.
8 *
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.
13 *
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.
18 *
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
22 * 02111-1307 USA
23 */
24
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>
31
32 #include <media/v4l2-device.h>
33
34 #include <sound/core.h>
35 #include <sound/initval.h>
36
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"
42
43 int cx18_alsa_debug;
44
45 #define CX18_DEBUG_ALSA_INFO(fmt, arg...) \
46 do { \
47 if (cx18_alsa_debug & 2) \
48 printk(KERN_INFO "%s: " fmt, "cx18-alsa", ## arg); \
49 } while (0);
50
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");
56
57 MODULE_AUTHOR("Andy Walls");
58 MODULE_DESCRIPTION("CX23418 ALSA Interface");
59 MODULE_SUPPORTED_DEVICE("CX23418 MPEG2 encoder");
60 MODULE_LICENSE("GPL");
61
62 MODULE_VERSION(CX18_VERSION);
63
64 static inline
to_snd_cx18_card(struct v4l2_device * v4l2_dev)65 struct snd_cx18_card *to_snd_cx18_card(struct v4l2_device *v4l2_dev)
66 {
67 return to_cx18(v4l2_dev)->alsa;
68 }
69
70 static inline
p_to_snd_cx18_card(struct v4l2_device ** v4l2_dev)71 struct snd_cx18_card *p_to_snd_cx18_card(struct v4l2_device **v4l2_dev)
72 {
73 return container_of(v4l2_dev, struct snd_cx18_card, v4l2_dev);
74 }
75
snd_cx18_card_free(struct snd_cx18_card * cxsc)76 static void snd_cx18_card_free(struct snd_cx18_card *cxsc)
77 {
78 if (cxsc == NULL)
79 return;
80
81 if (cxsc->v4l2_dev != NULL)
82 to_cx18(cxsc->v4l2_dev)->alsa = NULL;
83
84 /* FIXME - take any other stopping actions needed */
85
86 kfree(cxsc);
87 }
88
snd_cx18_card_private_free(struct snd_card * sc)89 static void snd_cx18_card_private_free(struct snd_card *sc)
90 {
91 if (sc == NULL)
92 return;
93 snd_cx18_card_free(sc->private_data);
94 sc->private_data = NULL;
95 sc->private_free = NULL;
96 }
97
snd_cx18_card_create(struct v4l2_device * v4l2_dev,struct snd_card * sc,struct snd_cx18_card ** cxsc)98 static int snd_cx18_card_create(struct v4l2_device *v4l2_dev,
99 struct snd_card *sc,
100 struct snd_cx18_card **cxsc)
101 {
102 *cxsc = kzalloc(sizeof(struct snd_cx18_card), GFP_KERNEL);
103 if (*cxsc == NULL)
104 return -ENOMEM;
105
106 (*cxsc)->v4l2_dev = v4l2_dev;
107 (*cxsc)->sc = sc;
108
109 sc->private_data = *cxsc;
110 sc->private_free = snd_cx18_card_private_free;
111
112 return 0;
113 }
114
snd_cx18_card_set_names(struct snd_cx18_card * cxsc)115 static int snd_cx18_card_set_names(struct snd_cx18_card *cxsc)
116 {
117 struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
118 struct snd_card *sc = cxsc->sc;
119
120 /* sc->driver is used by alsa-lib's configurator: simple, unique */
121 strlcpy(sc->driver, "CX23418", sizeof(sc->driver));
122
123 /* sc->shortname is a symlink in /proc/asound: CX18-M -> cardN */
124 snprintf(sc->shortname, sizeof(sc->shortname), "CX18-%d",
125 cx->instance);
126
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);
131
132 return 0;
133 }
134
snd_cx18_init(struct v4l2_device * v4l2_dev)135 static int snd_cx18_init(struct v4l2_device *v4l2_dev)
136 {
137 struct cx18 *cx = to_cx18(v4l2_dev);
138 struct snd_card *sc = NULL;
139 struct snd_cx18_card *cxsc;
140 int ret;
141
142 /* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */
143
144 /* (1) Check and increment the device index */
145 /* This is a no-op for us. We'll use the cx->instance */
146
147 /* (2) Create a card instance */
148 ret = snd_card_create(SNDRV_DEFAULT_IDX1, /* use first available id */
149 SNDRV_DEFAULT_STR1, /* xid from end of shortname*/
150 THIS_MODULE, 0, &sc);
151 if (ret) {
152 CX18_ALSA_ERR("%s: snd_card_create() failed with err %d\n",
153 __func__, ret);
154 goto err_exit;
155 }
156
157 /* (3) Create a main component */
158 ret = snd_cx18_card_create(v4l2_dev, sc, &cxsc);
159 if (ret) {
160 CX18_ALSA_ERR("%s: snd_cx18_card_create() failed with err %d\n",
161 __func__, ret);
162 goto err_exit_free;
163 }
164
165 /* (4) Set the driver ID and name strings */
166 snd_cx18_card_set_names(cxsc);
167
168
169 ret = snd_cx18_pcm_create(cxsc);
170 if (ret) {
171 CX18_ALSA_ERR("%s: snd_cx18_pcm_create() failed with err %d\n",
172 __func__, ret);
173 goto err_exit_free;
174 }
175 /* FIXME - proc files */
176
177 /* (7) Set the driver data and return 0 */
178 /* We do this out of normal order for PCI drivers to avoid races */
179 cx->alsa = cxsc;
180
181 /* (6) Register the card instance */
182 ret = snd_card_register(sc);
183 if (ret) {
184 cx->alsa = NULL;
185 CX18_ALSA_ERR("%s: snd_card_register() failed with err %d\n",
186 __func__, ret);
187 goto err_exit_free;
188 }
189
190 return 0;
191
192 err_exit_free:
193 if (sc != NULL)
194 snd_card_free(sc);
195 kfree(cxsc);
196 err_exit:
197 return ret;
198 }
199
cx18_alsa_load(struct cx18 * cx)200 int cx18_alsa_load(struct cx18 *cx)
201 {
202 struct v4l2_device *v4l2_dev = &cx->v4l2_dev;
203 struct cx18_stream *s;
204
205 if (v4l2_dev == NULL) {
206 printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
207 __func__);
208 return 0;
209 }
210
211 cx = to_cx18(v4l2_dev);
212 if (cx == NULL) {
213 printk(KERN_ERR "cx18-alsa cx is NULL\n");
214 return 0;
215 }
216
217 s = &cx->streams[CX18_ENC_STREAM_TYPE_PCM];
218 if (s->video_dev == NULL) {
219 CX18_DEBUG_ALSA_INFO("%s: PCM stream for card is disabled - "
220 "skipping\n", __func__);
221 return 0;
222 }
223
224 if (cx->alsa != NULL) {
225 CX18_ALSA_ERR("%s: struct snd_cx18_card * already exists\n",
226 __func__);
227 return 0;
228 }
229
230 if (snd_cx18_init(v4l2_dev)) {
231 CX18_ALSA_ERR("%s: failed to create struct snd_cx18_card\n",
232 __func__);
233 } else {
234 CX18_DEBUG_ALSA_INFO("%s: created cx18 ALSA interface instance "
235 "\n", __func__);
236 }
237 return 0;
238 }
239
cx18_alsa_init(void)240 static int __init cx18_alsa_init(void)
241 {
242 printk(KERN_INFO "cx18-alsa: module loading...\n");
243 cx18_ext_init = &cx18_alsa_load;
244 return 0;
245 }
246
snd_cx18_exit(struct snd_cx18_card * cxsc)247 static void __exit snd_cx18_exit(struct snd_cx18_card *cxsc)
248 {
249 struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
250
251 /* FIXME - pointer checks & shutdown cxsc */
252
253 snd_card_free(cxsc->sc);
254 cx->alsa = NULL;
255 }
256
cx18_alsa_exit_callback(struct device * dev,void * data)257 static int __exit cx18_alsa_exit_callback(struct device *dev, void *data)
258 {
259 struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
260 struct snd_cx18_card *cxsc;
261
262 if (v4l2_dev == NULL) {
263 printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
264 __func__);
265 return 0;
266 }
267
268 cxsc = to_snd_cx18_card(v4l2_dev);
269 if (cxsc == NULL) {
270 CX18_ALSA_WARN("%s: struct snd_cx18_card * is NULL\n",
271 __func__);
272 return 0;
273 }
274
275 snd_cx18_exit(cxsc);
276 return 0;
277 }
278
cx18_alsa_exit(void)279 static void __exit cx18_alsa_exit(void)
280 {
281 struct device_driver *drv;
282 int ret;
283
284 printk(KERN_INFO "cx18-alsa: module unloading...\n");
285
286 drv = driver_find("cx18", &pci_bus_type);
287 ret = driver_for_each_device(drv, NULL, NULL, cx18_alsa_exit_callback);
288
289 cx18_ext_init = NULL;
290 printk(KERN_INFO "cx18-alsa: module unload complete\n");
291 }
292
293 module_init(cx18_alsa_init);
294 module_exit(cx18_alsa_exit);
295