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 
20 #include "ivtv-driver.h"
21 #include "ivtv-version.h"
22 #include "ivtv-alsa.h"
23 #include "ivtv-alsa-pcm.h"
24 
25 #include <sound/core.h>
26 #include <sound/initval.h>
27 
28 int ivtv_alsa_debug;
29 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
30 
31 #define IVTV_DEBUG_ALSA_INFO(__fmt, __arg...) \
32 	do { \
33 		if (ivtv_alsa_debug & 2) \
34 			printk(KERN_INFO pr_fmt("%s: alsa:" __fmt),	\
35 			       __func__, ##__arg);			\
36 	} while (0)
37 
38 module_param_named(debug, ivtv_alsa_debug, int, 0644);
39 MODULE_PARM_DESC(debug,
40 		 "Debug level (bitmask). Default: 0\n"
41 		 "\t\t\t  1/0x0001: warning\n"
42 		 "\t\t\t  2/0x0002: info\n");
43 
44 module_param_array(index, int, NULL, 0444);
45 MODULE_PARM_DESC(index,
46 		 "Index value for IVTV ALSA capture interface(s).\n");
47 
48 MODULE_AUTHOR("Andy Walls");
49 MODULE_DESCRIPTION("CX23415/CX23416 ALSA Interface");
50 MODULE_SUPPORTED_DEVICE("CX23415/CX23416 MPEG2 encoder");
51 MODULE_LICENSE("GPL");
52 
53 MODULE_VERSION(IVTV_VERSION);
54 
55 static inline
56 struct snd_ivtv_card *to_snd_ivtv_card(struct v4l2_device *v4l2_dev)
57 {
58 	return to_ivtv(v4l2_dev)->alsa;
59 }
60 
61 static inline
62 struct snd_ivtv_card *p_to_snd_ivtv_card(struct v4l2_device **v4l2_dev)
63 {
64 	return container_of(v4l2_dev, struct snd_ivtv_card, v4l2_dev);
65 }
66 
67 static void snd_ivtv_card_free(struct snd_ivtv_card *itvsc)
68 {
69 	if (itvsc == NULL)
70 		return;
71 
72 	if (itvsc->v4l2_dev != NULL)
73 		to_ivtv(itvsc->v4l2_dev)->alsa = NULL;
74 
75 	/* FIXME - take any other stopping actions needed */
76 
77 	kfree(itvsc);
78 }
79 
80 static void snd_ivtv_card_private_free(struct snd_card *sc)
81 {
82 	if (sc == NULL)
83 		return;
84 	snd_ivtv_card_free(sc->private_data);
85 	sc->private_data = NULL;
86 	sc->private_free = NULL;
87 }
88 
89 static int snd_ivtv_card_create(struct v4l2_device *v4l2_dev,
90 				       struct snd_card *sc,
91 				       struct snd_ivtv_card **itvsc)
92 {
93 	*itvsc = kzalloc(sizeof(struct snd_ivtv_card), GFP_KERNEL);
94 	if (*itvsc == NULL)
95 		return -ENOMEM;
96 
97 	(*itvsc)->v4l2_dev = v4l2_dev;
98 	(*itvsc)->sc = sc;
99 
100 	sc->private_data = *itvsc;
101 	sc->private_free = snd_ivtv_card_private_free;
102 
103 	return 0;
104 }
105 
106 static int snd_ivtv_card_set_names(struct snd_ivtv_card *itvsc)
107 {
108 	struct ivtv *itv = to_ivtv(itvsc->v4l2_dev);
109 	struct snd_card *sc = itvsc->sc;
110 
111 	/* sc->driver is used by alsa-lib's configurator: simple, unique */
112 	strlcpy(sc->driver, "CX2341[56]", sizeof(sc->driver));
113 
114 	/* sc->shortname is a symlink in /proc/asound: IVTV-M -> cardN */
115 	snprintf(sc->shortname,  sizeof(sc->shortname), "IVTV-%d",
116 		 itv->instance);
117 
118 	/* sc->longname is read from /proc/asound/cards */
119 	snprintf(sc->longname, sizeof(sc->longname),
120 		 "CX2341[56] #%d %s TV/FM Radio/Line-In Capture",
121 		 itv->instance, itv->card_name);
122 
123 	return 0;
124 }
125 
126 static int snd_ivtv_init(struct v4l2_device *v4l2_dev)
127 {
128 	struct ivtv *itv = to_ivtv(v4l2_dev);
129 	struct snd_card *sc = NULL;
130 	struct snd_ivtv_card *itvsc;
131 	int ret, idx;
132 
133 	/* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */
134 
135 	/* (1) Check and increment the device index */
136 	/* This is a no-op for us.  We'll use the itv->instance */
137 
138 	/* (2) Create a card instance */
139 	/* use first available id if not specified otherwise*/
140 	idx = index[itv->instance] == -1 ? SNDRV_DEFAULT_IDX1 : index[itv->instance];
141 	ret = snd_card_new(&itv->pdev->dev,
142 			   idx,
143 			   SNDRV_DEFAULT_STR1, /* xid from end of shortname*/
144 			   THIS_MODULE, 0, &sc);
145 	if (ret) {
146 		IVTV_ALSA_ERR("%s: snd_card_new() failed with err %d\n",
147 			      __func__, ret);
148 		goto err_exit;
149 	}
150 
151 	/* (3) Create a main component */
152 	ret = snd_ivtv_card_create(v4l2_dev, sc, &itvsc);
153 	if (ret) {
154 		IVTV_ALSA_ERR("%s: snd_ivtv_card_create() failed with err %d\n",
155 			      __func__, ret);
156 		goto err_exit_free;
157 	}
158 
159 	/* (4) Set the driver ID and name strings */
160 	snd_ivtv_card_set_names(itvsc);
161 
162 	/* (5) Create other components: PCM, & proc files */
163 	ret = snd_ivtv_pcm_create(itvsc);
164 	if (ret) {
165 		IVTV_ALSA_ERR("%s: snd_ivtv_pcm_create() failed with err %d\n",
166 			      __func__, ret);
167 		goto err_exit_free;
168 	}
169 	/* FIXME - proc files */
170 
171 	/* (7) Set the driver data and return 0 */
172 	/* We do this out of normal order for PCI drivers to avoid races */
173 	itv->alsa = itvsc;
174 
175 	/* (6) Register the card instance */
176 	ret = snd_card_register(sc);
177 	if (ret) {
178 		itv->alsa = NULL;
179 		IVTV_ALSA_ERR("%s: snd_card_register() failed with err %d\n",
180 			      __func__, ret);
181 		goto err_exit_free;
182 	}
183 
184 	IVTV_ALSA_INFO("%s: Instance %d registered as ALSA card %d\n",
185 			 __func__, itv->instance, sc->number);
186 
187 	return 0;
188 
189 err_exit_free:
190 	if (sc != NULL)
191 		snd_card_free(sc);
192 	kfree(itvsc);
193 err_exit:
194 	return ret;
195 }
196 
197 static int ivtv_alsa_load(struct ivtv *itv)
198 {
199 	struct v4l2_device *v4l2_dev = &itv->v4l2_dev;
200 	struct ivtv_stream *s;
201 
202 	if (v4l2_dev == NULL) {
203 		pr_err("ivtv-alsa: %s: struct v4l2_device * is NULL\n",
204 		       __func__);
205 		return 0;
206 	}
207 
208 	itv = to_ivtv(v4l2_dev);
209 	if (itv == NULL) {
210 		pr_err("ivtv-alsa itv is NULL\n");
211 		return 0;
212 	}
213 
214 	s = &itv->streams[IVTV_ENC_STREAM_TYPE_PCM];
215 	if (s->vdev.v4l2_dev == NULL) {
216 		IVTV_DEBUG_ALSA_INFO("PCM stream for card is disabled - skipping\n");
217 		return 0;
218 	}
219 
220 	if (itv->alsa != NULL) {
221 		IVTV_ALSA_ERR("%s: struct snd_ivtv_card * already exists\n",
222 			      __func__);
223 		return 0;
224 	}
225 
226 	if (snd_ivtv_init(v4l2_dev)) {
227 		IVTV_ALSA_ERR("%s: failed to create struct snd_ivtv_card\n",
228 			      __func__);
229 	} else {
230 		IVTV_DEBUG_ALSA_INFO("created ivtv ALSA interface instance\n");
231 	}
232 	return 0;
233 }
234 
235 static int __init ivtv_alsa_init(void)
236 {
237 	pr_info("ivtv-alsa: module loading...\n");
238 	ivtv_ext_init = &ivtv_alsa_load;
239 	return 0;
240 }
241 
242 static void __exit snd_ivtv_exit(struct snd_ivtv_card *itvsc)
243 {
244 	struct ivtv *itv = to_ivtv(itvsc->v4l2_dev);
245 
246 	/* FIXME - pointer checks & shutdown itvsc */
247 
248 	snd_card_free(itvsc->sc);
249 	itv->alsa = NULL;
250 }
251 
252 static int __exit ivtv_alsa_exit_callback(struct device *dev, void *data)
253 {
254 	struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
255 	struct snd_ivtv_card *itvsc;
256 
257 	if (v4l2_dev == NULL) {
258 		pr_err("ivtv-alsa: %s: struct v4l2_device * is NULL\n",
259 		       __func__);
260 		return 0;
261 	}
262 
263 	itvsc = to_snd_ivtv_card(v4l2_dev);
264 	if (itvsc == NULL) {
265 		IVTV_ALSA_WARN("%s: struct snd_ivtv_card * is NULL\n",
266 			       __func__);
267 		return 0;
268 	}
269 
270 	snd_ivtv_exit(itvsc);
271 	return 0;
272 }
273 
274 static void __exit ivtv_alsa_exit(void)
275 {
276 	struct device_driver *drv;
277 	int ret;
278 
279 	pr_info("ivtv-alsa: module unloading...\n");
280 
281 	drv = driver_find("ivtv", &pci_bus_type);
282 	ret = driver_for_each_device(drv, NULL, NULL, ivtv_alsa_exit_callback);
283 	(void)ret;	/* suppress compiler warning */
284 
285 	ivtv_ext_init = NULL;
286 	pr_info("ivtv-alsa: module unload complete\n");
287 }
288 
289 module_init(ivtv_alsa_init);
290 module_exit(ivtv_alsa_exit);
291