xref: /linux/drivers/media/pci/ivtv/ivtv-alsa-main.c (revision b8d312aa075f33282565467662c4628dae0a2aff)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  ALSA interface to ivtv PCM capture streams
4  *
5  *  Copyright (C) 2009,2012  Andy Walls <awalls@md.metrocast.net>
6  *  Copyright (C) 2009  Devin Heitmueller <dheitmueller@kernellabs.com>
7  *
8  *  Portions of this work were sponsored by ONELAN Limited for the cx18 driver
9  */
10 
11 #include "ivtv-driver.h"
12 #include "ivtv-version.h"
13 #include "ivtv-alsa.h"
14 #include "ivtv-alsa-pcm.h"
15 
16 #include <sound/core.h>
17 #include <sound/initval.h>
18 
19 int ivtv_alsa_debug;
20 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
21 
22 #define IVTV_DEBUG_ALSA_INFO(__fmt, __arg...) \
23 	do { \
24 		if (ivtv_alsa_debug & 2) \
25 			printk(KERN_INFO pr_fmt("%s: alsa:" __fmt),	\
26 			       __func__, ##__arg);			\
27 	} while (0)
28 
29 module_param_named(debug, ivtv_alsa_debug, int, 0644);
30 MODULE_PARM_DESC(debug,
31 		 "Debug level (bitmask). Default: 0\n"
32 		 "\t\t\t  1/0x0001: warning\n"
33 		 "\t\t\t  2/0x0002: info\n");
34 
35 module_param_array(index, int, NULL, 0444);
36 MODULE_PARM_DESC(index,
37 		 "Index value for IVTV ALSA capture interface(s).\n");
38 
39 MODULE_AUTHOR("Andy Walls");
40 MODULE_DESCRIPTION("CX23415/CX23416 ALSA Interface");
41 MODULE_SUPPORTED_DEVICE("CX23415/CX23416 MPEG2 encoder");
42 MODULE_LICENSE("GPL");
43 
44 MODULE_VERSION(IVTV_VERSION);
45 
46 static inline
47 struct snd_ivtv_card *to_snd_ivtv_card(struct v4l2_device *v4l2_dev)
48 {
49 	return to_ivtv(v4l2_dev)->alsa;
50 }
51 
52 static inline
53 struct snd_ivtv_card *p_to_snd_ivtv_card(struct v4l2_device **v4l2_dev)
54 {
55 	return container_of(v4l2_dev, struct snd_ivtv_card, v4l2_dev);
56 }
57 
58 static void snd_ivtv_card_free(struct snd_ivtv_card *itvsc)
59 {
60 	if (itvsc == NULL)
61 		return;
62 
63 	if (itvsc->v4l2_dev != NULL)
64 		to_ivtv(itvsc->v4l2_dev)->alsa = NULL;
65 
66 	/* FIXME - take any other stopping actions needed */
67 
68 	kfree(itvsc);
69 }
70 
71 static void snd_ivtv_card_private_free(struct snd_card *sc)
72 {
73 	if (sc == NULL)
74 		return;
75 	snd_ivtv_card_free(sc->private_data);
76 	sc->private_data = NULL;
77 	sc->private_free = NULL;
78 }
79 
80 static int snd_ivtv_card_create(struct v4l2_device *v4l2_dev,
81 				       struct snd_card *sc,
82 				       struct snd_ivtv_card **itvsc)
83 {
84 	*itvsc = kzalloc(sizeof(struct snd_ivtv_card), GFP_KERNEL);
85 	if (*itvsc == NULL)
86 		return -ENOMEM;
87 
88 	(*itvsc)->v4l2_dev = v4l2_dev;
89 	(*itvsc)->sc = sc;
90 
91 	sc->private_data = *itvsc;
92 	sc->private_free = snd_ivtv_card_private_free;
93 
94 	return 0;
95 }
96 
97 static int snd_ivtv_card_set_names(struct snd_ivtv_card *itvsc)
98 {
99 	struct ivtv *itv = to_ivtv(itvsc->v4l2_dev);
100 	struct snd_card *sc = itvsc->sc;
101 
102 	/* sc->driver is used by alsa-lib's configurator: simple, unique */
103 	strscpy(sc->driver, "CX2341[56]", sizeof(sc->driver));
104 
105 	/* sc->shortname is a symlink in /proc/asound: IVTV-M -> cardN */
106 	snprintf(sc->shortname,  sizeof(sc->shortname), "IVTV-%d",
107 		 itv->instance);
108 
109 	/* sc->longname is read from /proc/asound/cards */
110 	snprintf(sc->longname, sizeof(sc->longname),
111 		 "CX2341[56] #%d %s TV/FM Radio/Line-In Capture",
112 		 itv->instance, itv->card_name);
113 
114 	return 0;
115 }
116 
117 static int snd_ivtv_init(struct v4l2_device *v4l2_dev)
118 {
119 	struct ivtv *itv = to_ivtv(v4l2_dev);
120 	struct snd_card *sc = NULL;
121 	struct snd_ivtv_card *itvsc;
122 	int ret, idx;
123 
124 	/* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */
125 
126 	/* (1) Check and increment the device index */
127 	/* This is a no-op for us.  We'll use the itv->instance */
128 
129 	/* (2) Create a card instance */
130 	/* use first available id if not specified otherwise*/
131 	idx = index[itv->instance] == -1 ? SNDRV_DEFAULT_IDX1 : index[itv->instance];
132 	ret = snd_card_new(&itv->pdev->dev,
133 			   idx,
134 			   SNDRV_DEFAULT_STR1, /* xid from end of shortname*/
135 			   THIS_MODULE, 0, &sc);
136 	if (ret) {
137 		IVTV_ALSA_ERR("%s: snd_card_new() failed with err %d\n",
138 			      __func__, ret);
139 		goto err_exit;
140 	}
141 
142 	/* (3) Create a main component */
143 	ret = snd_ivtv_card_create(v4l2_dev, sc, &itvsc);
144 	if (ret) {
145 		IVTV_ALSA_ERR("%s: snd_ivtv_card_create() failed with err %d\n",
146 			      __func__, ret);
147 		goto err_exit_free;
148 	}
149 
150 	/* (4) Set the driver ID and name strings */
151 	snd_ivtv_card_set_names(itvsc);
152 
153 	/* (5) Create other components: PCM, & proc files */
154 	ret = snd_ivtv_pcm_create(itvsc);
155 	if (ret) {
156 		IVTV_ALSA_ERR("%s: snd_ivtv_pcm_create() failed with err %d\n",
157 			      __func__, ret);
158 		goto err_exit_free;
159 	}
160 	/* FIXME - proc files */
161 
162 	/* (7) Set the driver data and return 0 */
163 	/* We do this out of normal order for PCI drivers to avoid races */
164 	itv->alsa = itvsc;
165 
166 	/* (6) Register the card instance */
167 	ret = snd_card_register(sc);
168 	if (ret) {
169 		itv->alsa = NULL;
170 		IVTV_ALSA_ERR("%s: snd_card_register() failed with err %d\n",
171 			      __func__, ret);
172 		goto err_exit_free;
173 	}
174 
175 	IVTV_ALSA_INFO("%s: Instance %d registered as ALSA card %d\n",
176 			 __func__, itv->instance, sc->number);
177 
178 	return 0;
179 
180 err_exit_free:
181 	if (sc != NULL)
182 		snd_card_free(sc);
183 	kfree(itvsc);
184 err_exit:
185 	return ret;
186 }
187 
188 static int ivtv_alsa_load(struct ivtv *itv)
189 {
190 	struct v4l2_device *v4l2_dev = &itv->v4l2_dev;
191 	struct ivtv_stream *s;
192 
193 	if (v4l2_dev == NULL) {
194 		pr_err("ivtv-alsa: %s: struct v4l2_device * is NULL\n",
195 		       __func__);
196 		return 0;
197 	}
198 
199 	itv = to_ivtv(v4l2_dev);
200 	if (itv == NULL) {
201 		pr_err("ivtv-alsa itv is NULL\n");
202 		return 0;
203 	}
204 
205 	s = &itv->streams[IVTV_ENC_STREAM_TYPE_PCM];
206 	if (s->vdev.v4l2_dev == NULL) {
207 		IVTV_DEBUG_ALSA_INFO("PCM stream for card is disabled - skipping\n");
208 		return 0;
209 	}
210 
211 	if (itv->alsa != NULL) {
212 		IVTV_ALSA_ERR("%s: struct snd_ivtv_card * already exists\n",
213 			      __func__);
214 		return 0;
215 	}
216 
217 	if (snd_ivtv_init(v4l2_dev)) {
218 		IVTV_ALSA_ERR("%s: failed to create struct snd_ivtv_card\n",
219 			      __func__);
220 	} else {
221 		IVTV_DEBUG_ALSA_INFO("created ivtv ALSA interface instance\n");
222 	}
223 	return 0;
224 }
225 
226 static int __init ivtv_alsa_init(void)
227 {
228 	pr_info("ivtv-alsa: module loading...\n");
229 	ivtv_ext_init = &ivtv_alsa_load;
230 	return 0;
231 }
232 
233 static void __exit snd_ivtv_exit(struct snd_ivtv_card *itvsc)
234 {
235 	struct ivtv *itv = to_ivtv(itvsc->v4l2_dev);
236 
237 	/* FIXME - pointer checks & shutdown itvsc */
238 
239 	snd_card_free(itvsc->sc);
240 	itv->alsa = NULL;
241 }
242 
243 static int __exit ivtv_alsa_exit_callback(struct device *dev, void *data)
244 {
245 	struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
246 	struct snd_ivtv_card *itvsc;
247 
248 	if (v4l2_dev == NULL) {
249 		pr_err("ivtv-alsa: %s: struct v4l2_device * is NULL\n",
250 		       __func__);
251 		return 0;
252 	}
253 
254 	itvsc = to_snd_ivtv_card(v4l2_dev);
255 	if (itvsc == NULL) {
256 		IVTV_ALSA_WARN("%s: struct snd_ivtv_card * is NULL\n",
257 			       __func__);
258 		return 0;
259 	}
260 
261 	snd_ivtv_exit(itvsc);
262 	return 0;
263 }
264 
265 static void __exit ivtv_alsa_exit(void)
266 {
267 	struct device_driver *drv;
268 	int ret;
269 
270 	pr_info("ivtv-alsa: module unloading...\n");
271 
272 	drv = driver_find("ivtv", &pci_bus_type);
273 	ret = driver_for_each_device(drv, NULL, NULL, ivtv_alsa_exit_callback);
274 	(void)ret;	/* suppress compiler warning */
275 
276 	ivtv_ext_init = NULL;
277 	pr_info("ivtv-alsa: module unload complete\n");
278 }
279 
280 module_init(ivtv_alsa_init);
281 module_exit(ivtv_alsa_exit);
282