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 
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 
51 module_param_named(debug, ivtv_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("CX23415/CX23416 ALSA Interface");
59 MODULE_SUPPORTED_DEVICE("CX23415/CX23416 MPEG2 encoder");
60 MODULE_LICENSE("GPL");
61 
62 MODULE_VERSION(IVTV_VERSION);
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_new(&itv->pdev->dev,
149 			   SNDRV_DEFAULT_IDX1, /* use first available id */
150 			   SNDRV_DEFAULT_STR1, /* xid from end of shortname*/
151 			   THIS_MODULE, 0, &sc);
152 	if (ret) {
153 		IVTV_ALSA_ERR("%s: snd_card_new() failed with err %d\n",
154 			      __func__, ret);
155 		goto err_exit;
156 	}
157 
158 	/* (3) Create a main component */
159 	ret = snd_ivtv_card_create(v4l2_dev, sc, &itvsc);
160 	if (ret) {
161 		IVTV_ALSA_ERR("%s: snd_ivtv_card_create() failed with err %d\n",
162 			      __func__, ret);
163 		goto err_exit_free;
164 	}
165 
166 	/* (4) Set the driver ID and name strings */
167 	snd_ivtv_card_set_names(itvsc);
168 
169 	/* (5) Create other components: mixer, PCM, & proc files */
170 #if 0
171 	ret = snd_ivtv_mixer_create(itvsc);
172 	if (ret) {
173 		IVTV_ALSA_WARN("%s: snd_ivtv_mixer_create() failed with err %d:"
174 			       " proceeding anyway\n", __func__, ret);
175 	}
176 #endif
177 
178 	ret = snd_ivtv_pcm_create(itvsc);
179 	if (ret) {
180 		IVTV_ALSA_ERR("%s: snd_ivtv_pcm_create() failed with err %d\n",
181 			      __func__, ret);
182 		goto err_exit_free;
183 	}
184 	/* FIXME - proc files */
185 
186 	/* (7) Set the driver data and return 0 */
187 	/* We do this out of normal order for PCI drivers to avoid races */
188 	itv->alsa = itvsc;
189 
190 	/* (6) Register the card instance */
191 	ret = snd_card_register(sc);
192 	if (ret) {
193 		itv->alsa = NULL;
194 		IVTV_ALSA_ERR("%s: snd_card_register() failed with err %d\n",
195 			      __func__, ret);
196 		goto err_exit_free;
197 	}
198 
199 	return 0;
200 
201 err_exit_free:
202 	if (sc != NULL)
203 		snd_card_free(sc);
204 	kfree(itvsc);
205 err_exit:
206 	return ret;
207 }
208 
209 static int ivtv_alsa_load(struct ivtv *itv)
210 {
211 	struct v4l2_device *v4l2_dev = &itv->v4l2_dev;
212 	struct ivtv_stream *s;
213 
214 	if (v4l2_dev == NULL) {
215 		pr_err("ivtv-alsa: %s: struct v4l2_device * is NULL\n",
216 		       __func__);
217 		return 0;
218 	}
219 
220 	itv = to_ivtv(v4l2_dev);
221 	if (itv == NULL) {
222 		pr_err("ivtv-alsa itv is NULL\n");
223 		return 0;
224 	}
225 
226 	s = &itv->streams[IVTV_ENC_STREAM_TYPE_PCM];
227 	if (s->vdev.v4l2_dev == NULL) {
228 		IVTV_DEBUG_ALSA_INFO("%s: PCM stream for card is disabled - "
229 				     "skipping\n", __func__);
230 		return 0;
231 	}
232 
233 	if (itv->alsa != NULL) {
234 		IVTV_ALSA_ERR("%s: struct snd_ivtv_card * already exists\n",
235 			      __func__);
236 		return 0;
237 	}
238 
239 	if (snd_ivtv_init(v4l2_dev)) {
240 		IVTV_ALSA_ERR("%s: failed to create struct snd_ivtv_card\n",
241 			      __func__);
242 	} else {
243 		IVTV_DEBUG_ALSA_INFO("%s: created ivtv ALSA interface instance "
244 				     "\n", __func__);
245 	}
246 	return 0;
247 }
248 
249 static int __init ivtv_alsa_init(void)
250 {
251 	pr_info("ivtv-alsa: module loading...\n");
252 	ivtv_ext_init = &ivtv_alsa_load;
253 	return 0;
254 }
255 
256 static void __exit snd_ivtv_exit(struct snd_ivtv_card *itvsc)
257 {
258 	struct ivtv *itv = to_ivtv(itvsc->v4l2_dev);
259 
260 	/* FIXME - pointer checks & shutdown itvsc */
261 
262 	snd_card_free(itvsc->sc);
263 	itv->alsa = NULL;
264 }
265 
266 static int __exit ivtv_alsa_exit_callback(struct device *dev, void *data)
267 {
268 	struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
269 	struct snd_ivtv_card *itvsc;
270 
271 	if (v4l2_dev == NULL) {
272 		pr_err("ivtv-alsa: %s: struct v4l2_device * is NULL\n",
273 		       __func__);
274 		return 0;
275 	}
276 
277 	itvsc = to_snd_ivtv_card(v4l2_dev);
278 	if (itvsc == NULL) {
279 		IVTV_ALSA_WARN("%s: struct snd_ivtv_card * is NULL\n",
280 			       __func__);
281 		return 0;
282 	}
283 
284 	snd_ivtv_exit(itvsc);
285 	return 0;
286 }
287 
288 static void __exit ivtv_alsa_exit(void)
289 {
290 	struct device_driver *drv;
291 	int ret;
292 
293 	pr_info("ivtv-alsa: module unloading...\n");
294 
295 	drv = driver_find("ivtv", &pci_bus_type);
296 	ret = driver_for_each_device(drv, NULL, NULL, ivtv_alsa_exit_callback);
297 	(void)ret;	/* suppress compiler warning */
298 
299 	ivtv_ext_init = NULL;
300 	pr_info("ivtv-alsa: module unload complete\n");
301 }
302 
303 module_init(ivtv_alsa_init);
304 module_exit(ivtv_alsa_exit);
305