1 /*
2  *  ALSA interface to ivtv PCM capture streams
3  *
4  *  Copyright (C) 2009,2012  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 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 
43 int ivtv_alsa_debug;
44 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
45 
46 #define IVTV_DEBUG_ALSA_INFO(fmt, arg...) \
47 	do { \
48 		if (ivtv_alsa_debug & 2) \
49 			pr_info("%s: " fmt, "ivtv-alsa", ## arg); \
50 	} while (0)
51 
52 module_param_named(debug, ivtv_alsa_debug, int, 0644);
53 MODULE_PARM_DESC(debug,
54 		 "Debug level (bitmask). Default: 0\n"
55 		 "\t\t\t  1/0x0001: warning\n"
56 		 "\t\t\t  2/0x0002: info\n");
57 
58 module_param_array(index, int, NULL, 0444);
59 MODULE_PARM_DESC(index,
60 		 "Index value for IVTV ALSA capture interface(s).\n");
61 
62 MODULE_AUTHOR("Andy Walls");
63 MODULE_DESCRIPTION("CX23415/CX23416 ALSA Interface");
64 MODULE_SUPPORTED_DEVICE("CX23415/CX23416 MPEG2 encoder");
65 MODULE_LICENSE("GPL");
66 
67 MODULE_VERSION(IVTV_VERSION);
68 
69 static inline
70 struct snd_ivtv_card *to_snd_ivtv_card(struct v4l2_device *v4l2_dev)
71 {
72 	return to_ivtv(v4l2_dev)->alsa;
73 }
74 
75 static inline
76 struct snd_ivtv_card *p_to_snd_ivtv_card(struct v4l2_device **v4l2_dev)
77 {
78 	return container_of(v4l2_dev, struct snd_ivtv_card, v4l2_dev);
79 }
80 
81 static void snd_ivtv_card_free(struct snd_ivtv_card *itvsc)
82 {
83 	if (itvsc == NULL)
84 		return;
85 
86 	if (itvsc->v4l2_dev != NULL)
87 		to_ivtv(itvsc->v4l2_dev)->alsa = NULL;
88 
89 	/* FIXME - take any other stopping actions needed */
90 
91 	kfree(itvsc);
92 }
93 
94 static void snd_ivtv_card_private_free(struct snd_card *sc)
95 {
96 	if (sc == NULL)
97 		return;
98 	snd_ivtv_card_free(sc->private_data);
99 	sc->private_data = NULL;
100 	sc->private_free = NULL;
101 }
102 
103 static int snd_ivtv_card_create(struct v4l2_device *v4l2_dev,
104 				       struct snd_card *sc,
105 				       struct snd_ivtv_card **itvsc)
106 {
107 	*itvsc = kzalloc(sizeof(struct snd_ivtv_card), GFP_KERNEL);
108 	if (*itvsc == NULL)
109 		return -ENOMEM;
110 
111 	(*itvsc)->v4l2_dev = v4l2_dev;
112 	(*itvsc)->sc = sc;
113 
114 	sc->private_data = *itvsc;
115 	sc->private_free = snd_ivtv_card_private_free;
116 
117 	return 0;
118 }
119 
120 static int snd_ivtv_card_set_names(struct snd_ivtv_card *itvsc)
121 {
122 	struct ivtv *itv = to_ivtv(itvsc->v4l2_dev);
123 	struct snd_card *sc = itvsc->sc;
124 
125 	/* sc->driver is used by alsa-lib's configurator: simple, unique */
126 	strlcpy(sc->driver, "CX2341[56]", sizeof(sc->driver));
127 
128 	/* sc->shortname is a symlink in /proc/asound: IVTV-M -> cardN */
129 	snprintf(sc->shortname,  sizeof(sc->shortname), "IVTV-%d",
130 		 itv->instance);
131 
132 	/* sc->longname is read from /proc/asound/cards */
133 	snprintf(sc->longname, sizeof(sc->longname),
134 		 "CX2341[56] #%d %s TV/FM Radio/Line-In Capture",
135 		 itv->instance, itv->card_name);
136 
137 	return 0;
138 }
139 
140 static int snd_ivtv_init(struct v4l2_device *v4l2_dev)
141 {
142 	struct ivtv *itv = to_ivtv(v4l2_dev);
143 	struct snd_card *sc = NULL;
144 	struct snd_ivtv_card *itvsc;
145 	int ret, idx;
146 
147 	/* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */
148 
149 	/* (1) Check and increment the device index */
150 	/* This is a no-op for us.  We'll use the itv->instance */
151 
152 	/* (2) Create a card instance */
153 	/* use first available id if not specified otherwise*/
154 	idx = index[itv->instance] == -1 ? SNDRV_DEFAULT_IDX1 : index[itv->instance];
155 	ret = snd_card_new(&itv->pdev->dev,
156 			   idx,
157 			   SNDRV_DEFAULT_STR1, /* xid from end of shortname*/
158 			   THIS_MODULE, 0, &sc);
159 	if (ret) {
160 		IVTV_ALSA_ERR("%s: snd_card_new() failed with err %d\n",
161 			      __func__, ret);
162 		goto err_exit;
163 	}
164 
165 	/* (3) Create a main component */
166 	ret = snd_ivtv_card_create(v4l2_dev, sc, &itvsc);
167 	if (ret) {
168 		IVTV_ALSA_ERR("%s: snd_ivtv_card_create() failed with err %d\n",
169 			      __func__, ret);
170 		goto err_exit_free;
171 	}
172 
173 	/* (4) Set the driver ID and name strings */
174 	snd_ivtv_card_set_names(itvsc);
175 
176 	/* (5) Create other components: mixer, PCM, & proc files */
177 #if 0
178 	ret = snd_ivtv_mixer_create(itvsc);
179 	if (ret) {
180 		IVTV_ALSA_WARN("%s: snd_ivtv_mixer_create() failed with err %d:"
181 			       " proceeding anyway\n", __func__, ret);
182 	}
183 #endif
184 
185 	ret = snd_ivtv_pcm_create(itvsc);
186 	if (ret) {
187 		IVTV_ALSA_ERR("%s: snd_ivtv_pcm_create() failed with err %d\n",
188 			      __func__, ret);
189 		goto err_exit_free;
190 	}
191 	/* FIXME - proc files */
192 
193 	/* (7) Set the driver data and return 0 */
194 	/* We do this out of normal order for PCI drivers to avoid races */
195 	itv->alsa = itvsc;
196 
197 	/* (6) Register the card instance */
198 	ret = snd_card_register(sc);
199 	if (ret) {
200 		itv->alsa = NULL;
201 		IVTV_ALSA_ERR("%s: snd_card_register() failed with err %d\n",
202 			      __func__, ret);
203 		goto err_exit_free;
204 	}
205 
206 	IVTV_ALSA_INFO("%s: Instance %d registered as ALSA card %d\n",
207 			 __func__, itv->instance, sc->number);
208 
209 	return 0;
210 
211 err_exit_free:
212 	if (sc != NULL)
213 		snd_card_free(sc);
214 	kfree(itvsc);
215 err_exit:
216 	return ret;
217 }
218 
219 static int ivtv_alsa_load(struct ivtv *itv)
220 {
221 	struct v4l2_device *v4l2_dev = &itv->v4l2_dev;
222 	struct ivtv_stream *s;
223 
224 	if (v4l2_dev == NULL) {
225 		pr_err("ivtv-alsa: %s: struct v4l2_device * is NULL\n",
226 		       __func__);
227 		return 0;
228 	}
229 
230 	itv = to_ivtv(v4l2_dev);
231 	if (itv == NULL) {
232 		pr_err("ivtv-alsa itv is NULL\n");
233 		return 0;
234 	}
235 
236 	s = &itv->streams[IVTV_ENC_STREAM_TYPE_PCM];
237 	if (s->vdev.v4l2_dev == NULL) {
238 		IVTV_DEBUG_ALSA_INFO("%s: PCM stream for card is disabled - "
239 				     "skipping\n", __func__);
240 		return 0;
241 	}
242 
243 	if (itv->alsa != NULL) {
244 		IVTV_ALSA_ERR("%s: struct snd_ivtv_card * already exists\n",
245 			      __func__);
246 		return 0;
247 	}
248 
249 	if (snd_ivtv_init(v4l2_dev)) {
250 		IVTV_ALSA_ERR("%s: failed to create struct snd_ivtv_card\n",
251 			      __func__);
252 	} else {
253 		IVTV_DEBUG_ALSA_INFO("%s: created ivtv ALSA interface instance "
254 				     "\n", __func__);
255 	}
256 	return 0;
257 }
258 
259 static int __init ivtv_alsa_init(void)
260 {
261 	pr_info("ivtv-alsa: module loading...\n");
262 	ivtv_ext_init = &ivtv_alsa_load;
263 	return 0;
264 }
265 
266 static void __exit snd_ivtv_exit(struct snd_ivtv_card *itvsc)
267 {
268 	struct ivtv *itv = to_ivtv(itvsc->v4l2_dev);
269 
270 	/* FIXME - pointer checks & shutdown itvsc */
271 
272 	snd_card_free(itvsc->sc);
273 	itv->alsa = NULL;
274 }
275 
276 static int __exit ivtv_alsa_exit_callback(struct device *dev, void *data)
277 {
278 	struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
279 	struct snd_ivtv_card *itvsc;
280 
281 	if (v4l2_dev == NULL) {
282 		pr_err("ivtv-alsa: %s: struct v4l2_device * is NULL\n",
283 		       __func__);
284 		return 0;
285 	}
286 
287 	itvsc = to_snd_ivtv_card(v4l2_dev);
288 	if (itvsc == NULL) {
289 		IVTV_ALSA_WARN("%s: struct snd_ivtv_card * is NULL\n",
290 			       __func__);
291 		return 0;
292 	}
293 
294 	snd_ivtv_exit(itvsc);
295 	return 0;
296 }
297 
298 static void __exit ivtv_alsa_exit(void)
299 {
300 	struct device_driver *drv;
301 	int ret;
302 
303 	pr_info("ivtv-alsa: module unloading...\n");
304 
305 	drv = driver_find("ivtv", &pci_bus_type);
306 	ret = driver_for_each_device(drv, NULL, NULL, ivtv_alsa_exit_callback);
307 	(void)ret;	/* suppress compiler warning */
308 
309 	ivtv_ext_init = NULL;
310 	pr_info("ivtv-alsa: module unload complete\n");
311 }
312 
313 module_init(ivtv_alsa_init);
314 module_exit(ivtv_alsa_exit);
315