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ivtv-alsa-main.c
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1 /*
2  * ALSA interface to ivtv PCM capture streams
3  *
4  * Copyright (C) 2009,2012 Andy Walls <[email protected]>
5  * Copyright (C) 2009 Devin Heitmueller <[email protected]>
6  *
7  * Portions of this work were sponsored by ONELAN Limited for the cx18 driver
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 "ivtv-driver.h"
38 #include "ivtv-version.h"
39 #include "ivtv-alsa.h"
40 #include "ivtv-alsa-mixer.h"
41 #include "ivtv-alsa-pcm.h"
42 
44 
45 #define IVTV_DEBUG_ALSA_INFO(fmt, arg...) \
46  do { \
47  if (ivtv_alsa_debug & 2) \
48  pr_info("%s: " fmt, "ivtv-alsa", ## arg); \
49  } while (0)
50 
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("CX23415/CX23416 ALSA Interface");
59 MODULE_SUPPORTED_DEVICE("CX23415/CX23416 MPEG2 encoder");
60 MODULE_LICENSE("GPL");
61 
63 
64 static inline
65 struct snd_ivtv_card *to_snd_ivtv_card(struct v4l2_device *v4l2_dev)
66 {
67  return to_ivtv(v4l2_dev)->alsa;
68 }
69 
70 static inline
71 struct snd_ivtv_card *p_to_snd_ivtv_card(struct v4l2_device **v4l2_dev)
72 {
73  return container_of(v4l2_dev, struct snd_ivtv_card, v4l2_dev);
74 }
75 
76 static void snd_ivtv_card_free(struct snd_ivtv_card *itvsc)
77 {
78  if (itvsc == NULL)
79  return;
80 
81  if (itvsc->v4l2_dev != NULL)
82  to_ivtv(itvsc->v4l2_dev)->alsa = NULL;
83 
84  /* FIXME - take any other stopping actions needed */
85 
86  kfree(itvsc);
87 }
88 
89 static void snd_ivtv_card_private_free(struct snd_card *sc)
90 {
91  if (sc == NULL)
92  return;
93  snd_ivtv_card_free(sc->private_data);
94  sc->private_data = NULL;
95  sc->private_free = NULL;
96 }
97 
98 static int snd_ivtv_card_create(struct v4l2_device *v4l2_dev,
99  struct snd_card *sc,
100  struct snd_ivtv_card **itvsc)
101 {
102  *itvsc = kzalloc(sizeof(struct snd_ivtv_card), GFP_KERNEL);
103  if (*itvsc == NULL)
104  return -ENOMEM;
105 
106  (*itvsc)->v4l2_dev = v4l2_dev;
107  (*itvsc)->sc = sc;
108 
109  sc->private_data = *itvsc;
110  sc->private_free = snd_ivtv_card_private_free;
111 
112  return 0;
113 }
114 
115 static int snd_ivtv_card_set_names(struct snd_ivtv_card *itvsc)
116 {
117  struct ivtv *itv = to_ivtv(itvsc->v4l2_dev);
118  struct snd_card *sc = itvsc->sc;
119 
120  /* sc->driver is used by alsa-lib's configurator: simple, unique */
121  strlcpy(sc->driver, "CX2341[56]", sizeof(sc->driver));
122 
123  /* sc->shortname is a symlink in /proc/asound: IVTV-M -> cardN */
124  snprintf(sc->shortname, sizeof(sc->shortname), "IVTV-%d",
125  itv->instance);
126 
127  /* sc->longname is read from /proc/asound/cards */
128  snprintf(sc->longname, sizeof(sc->longname),
129  "CX2341[56] #%d %s TV/FM Radio/Line-In Capture",
130  itv->instance, itv->card_name);
131 
132  return 0;
133 }
134 
135 static int snd_ivtv_init(struct v4l2_device *v4l2_dev)
136 {
137  struct ivtv *itv = to_ivtv(v4l2_dev);
138  struct snd_card *sc = NULL;
139  struct snd_ivtv_card *itvsc;
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 itv->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  IVTV_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_ivtv_card_create(v4l2_dev, sc, &itvsc);
159  if (ret) {
160  IVTV_ALSA_ERR("%s: snd_ivtv_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_ivtv_card_set_names(itvsc);
167 
168  /* (5) Create other components: mixer, PCM, & proc files */
169 #if 0
170  ret = snd_ivtv_mixer_create(itvsc);
171  if (ret) {
172  IVTV_ALSA_WARN("%s: snd_ivtv_mixer_create() failed with err %d:"
173  " proceeding anyway\n", __func__, ret);
174  }
175 #endif
176 
177  ret = snd_ivtv_pcm_create(itvsc);
178  if (ret) {
179  IVTV_ALSA_ERR("%s: snd_ivtv_pcm_create() failed with err %d\n",
180  __func__, ret);
181  goto err_exit_free;
182  }
183  /* FIXME - proc files */
184 
185  /* (7) Set the driver data and return 0 */
186  /* We do this out of normal order for PCI drivers to avoid races */
187  itv->alsa = itvsc;
188 
189  /* (6) Register the card instance */
190  ret = snd_card_register(sc);
191  if (ret) {
192  itv->alsa = NULL;
193  IVTV_ALSA_ERR("%s: snd_card_register() failed with err %d\n",
194  __func__, ret);
195  goto err_exit_free;
196  }
197 
198  return 0;
199 
200 err_exit_free:
201  if (sc != NULL)
202  snd_card_free(sc);
203  kfree(itvsc);
204 err_exit:
205  return ret;
206 }
207 
208 int ivtv_alsa_load(struct ivtv *itv)
209 {
210  struct v4l2_device *v4l2_dev = &itv->v4l2_dev;
211  struct ivtv_stream *s;
212 
213  if (v4l2_dev == NULL) {
214  pr_err("ivtv-alsa: %s: struct v4l2_device * is NULL\n",
215  __func__);
216  return 0;
217  }
218 
219  itv = to_ivtv(v4l2_dev);
220  if (itv == NULL) {
221  pr_err("ivtv-alsa itv is NULL\n");
222  return 0;
223  }
224 
226  if (s->vdev == NULL) {
227  IVTV_DEBUG_ALSA_INFO("%s: PCM stream for card is disabled - "
228  "skipping\n", __func__);
229  return 0;
230  }
231 
232  if (itv->alsa != NULL) {
233  IVTV_ALSA_ERR("%s: struct snd_ivtv_card * already exists\n",
234  __func__);
235  return 0;
236  }
237 
238  if (snd_ivtv_init(v4l2_dev)) {
239  IVTV_ALSA_ERR("%s: failed to create struct snd_ivtv_card\n",
240  __func__);
241  } else {
242  IVTV_DEBUG_ALSA_INFO("%s: created ivtv ALSA interface instance "
243  "\n", __func__);
244  }
245  return 0;
246 }
247 
248 static int __init ivtv_alsa_init(void)
249 {
250  pr_info("ivtv-alsa: module loading...\n");
252  return 0;
253 }
254 
255 static void __exit snd_ivtv_exit(struct snd_ivtv_card *itvsc)
256 {
257  struct ivtv *itv = to_ivtv(itvsc->v4l2_dev);
258 
259  /* FIXME - pointer checks & shutdown itvsc */
260 
261  snd_card_free(itvsc->sc);
262  itv->alsa = NULL;
263 }
264 
265 static int __exit ivtv_alsa_exit_callback(struct device *dev, void *data)
266 {
267  struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
268  struct snd_ivtv_card *itvsc;
269 
270  if (v4l2_dev == NULL) {
271  pr_err("ivtv-alsa: %s: struct v4l2_device * is NULL\n",
272  __func__);
273  return 0;
274  }
275 
276  itvsc = to_snd_ivtv_card(v4l2_dev);
277  if (itvsc == NULL) {
278  IVTV_ALSA_WARN("%s: struct snd_ivtv_card * is NULL\n",
279  __func__);
280  return 0;
281  }
282 
283  snd_ivtv_exit(itvsc);
284  return 0;
285 }
286 
287 static void __exit ivtv_alsa_exit(void)
288 {
289  struct device_driver *drv;
290  int ret;
291 
292  pr_info("ivtv-alsa: module unloading...\n");
293 
294  drv = driver_find("ivtv", &pci_bus_type);
295  ret = driver_for_each_device(drv, NULL, NULL, ivtv_alsa_exit_callback);
296  (void)ret; /* suppress compiler warning */
297 
299  pr_info("ivtv-alsa: module unload complete\n");
300 }
301 
302 module_init(ivtv_alsa_init);
303 module_exit(ivtv_alsa_exit);