xref: /linux/drivers/media/pci/ivtv/ivtv-alsa-main.c (revision 02680c23d7b3febe45ea3d4f9818c2b2dc89020a)
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_LICENSE("GPL");
42 
43 MODULE_VERSION(IVTV_VERSION);
44 
45 static inline
46 struct snd_ivtv_card *to_snd_ivtv_card(struct v4l2_device *v4l2_dev)
47 {
48 	return to_ivtv(v4l2_dev)->alsa;
49 }
50 
51 static inline
52 struct snd_ivtv_card *p_to_snd_ivtv_card(struct v4l2_device **v4l2_dev)
53 {
54 	return container_of(v4l2_dev, struct snd_ivtv_card, v4l2_dev);
55 }
56 
57 static void snd_ivtv_card_free(struct snd_ivtv_card *itvsc)
58 {
59 	if (itvsc == NULL)
60 		return;
61 
62 	if (itvsc->v4l2_dev != NULL)
63 		to_ivtv(itvsc->v4l2_dev)->alsa = NULL;
64 
65 	/* FIXME - take any other stopping actions needed */
66 
67 	kfree(itvsc);
68 }
69 
70 static void snd_ivtv_card_private_free(struct snd_card *sc)
71 {
72 	if (sc == NULL)
73 		return;
74 	snd_ivtv_card_free(sc->private_data);
75 	sc->private_data = NULL;
76 	sc->private_free = NULL;
77 }
78 
79 static int snd_ivtv_card_create(struct v4l2_device *v4l2_dev,
80 				       struct snd_card *sc,
81 				       struct snd_ivtv_card **itvsc)
82 {
83 	*itvsc = kzalloc(sizeof(struct snd_ivtv_card), GFP_KERNEL);
84 	if (*itvsc == NULL)
85 		return -ENOMEM;
86 
87 	(*itvsc)->v4l2_dev = v4l2_dev;
88 	(*itvsc)->sc = sc;
89 
90 	sc->private_data = *itvsc;
91 	sc->private_free = snd_ivtv_card_private_free;
92 
93 	return 0;
94 }
95 
96 static int snd_ivtv_card_set_names(struct snd_ivtv_card *itvsc)
97 {
98 	struct ivtv *itv = to_ivtv(itvsc->v4l2_dev);
99 	struct snd_card *sc = itvsc->sc;
100 
101 	/* sc->driver is used by alsa-lib's configurator: simple, unique */
102 	strscpy(sc->driver, "CX2341[56]", sizeof(sc->driver));
103 
104 	/* sc->shortname is a symlink in /proc/asound: IVTV-M -> cardN */
105 	snprintf(sc->shortname,  sizeof(sc->shortname), "IVTV-%d",
106 		 itv->instance);
107 
108 	/* sc->longname is read from /proc/asound/cards */
109 	snprintf(sc->longname, sizeof(sc->longname),
110 		 "CX2341[56] #%d %s TV/FM Radio/Line-In Capture",
111 		 itv->instance, itv->card_name);
112 
113 	return 0;
114 }
115 
116 static int snd_ivtv_init(struct v4l2_device *v4l2_dev)
117 {
118 	struct ivtv *itv = to_ivtv(v4l2_dev);
119 	struct snd_card *sc = NULL;
120 	struct snd_ivtv_card *itvsc;
121 	int ret, idx;
122 
123 	/* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */
124 
125 	/* (1) Check and increment the device index */
126 	/* This is a no-op for us.  We'll use the itv->instance */
127 
128 	/* (2) Create a card instance */
129 	/* use first available id if not specified otherwise*/
130 	idx = index[itv->instance] == -1 ? SNDRV_DEFAULT_IDX1 : index[itv->instance];
131 	ret = snd_card_new(&itv->pdev->dev,
132 			   idx,
133 			   SNDRV_DEFAULT_STR1, /* xid from end of shortname*/
134 			   THIS_MODULE, 0, &sc);
135 	if (ret) {
136 		IVTV_ALSA_ERR("%s: snd_card_new() failed with err %d\n",
137 			      __func__, ret);
138 		goto err_exit;
139 	}
140 
141 	/* (3) Create a main component */
142 	ret = snd_ivtv_card_create(v4l2_dev, sc, &itvsc);
143 	if (ret) {
144 		IVTV_ALSA_ERR("%s: snd_ivtv_card_create() failed with err %d\n",
145 			      __func__, ret);
146 		goto err_exit_free;
147 	}
148 
149 	/* (4) Set the driver ID and name strings */
150 	snd_ivtv_card_set_names(itvsc);
151 
152 	/* (5) Create other components: PCM, & proc files */
153 	ret = snd_ivtv_pcm_create(itvsc);
154 	if (ret) {
155 		IVTV_ALSA_ERR("%s: snd_ivtv_pcm_create() failed with err %d\n",
156 			      __func__, ret);
157 		goto err_exit_free;
158 	}
159 	/* FIXME - proc files */
160 
161 	/* (7) Set the driver data and return 0 */
162 	/* We do this out of normal order for PCI drivers to avoid races */
163 	itv->alsa = itvsc;
164 
165 	/* (6) Register the card instance */
166 	ret = snd_card_register(sc);
167 	if (ret) {
168 		itv->alsa = NULL;
169 		IVTV_ALSA_ERR("%s: snd_card_register() failed with err %d\n",
170 			      __func__, ret);
171 		goto err_exit_free;
172 	}
173 
174 	IVTV_ALSA_INFO("%s: Instance %d registered as ALSA card %d\n",
175 			 __func__, itv->instance, sc->number);
176 
177 	return 0;
178 
179 err_exit_free:
180 	if (sc != NULL)
181 		snd_card_free(sc);
182 	kfree(itvsc);
183 err_exit:
184 	return ret;
185 }
186 
187 static int ivtv_alsa_load(struct ivtv *itv)
188 {
189 	struct v4l2_device *v4l2_dev = &itv->v4l2_dev;
190 	struct ivtv_stream *s;
191 
192 	if (v4l2_dev == NULL) {
193 		pr_err("ivtv-alsa: %s: struct v4l2_device * is NULL\n",
194 		       __func__);
195 		return 0;
196 	}
197 
198 	itv = to_ivtv(v4l2_dev);
199 	if (itv == NULL) {
200 		pr_err("ivtv-alsa itv is NULL\n");
201 		return 0;
202 	}
203 
204 	s = &itv->streams[IVTV_ENC_STREAM_TYPE_PCM];
205 	if (s->vdev.v4l2_dev == NULL) {
206 		IVTV_DEBUG_ALSA_INFO("PCM stream for card is disabled - skipping\n");
207 		return 0;
208 	}
209 
210 	if (itv->alsa != NULL) {
211 		IVTV_ALSA_ERR("%s: struct snd_ivtv_card * already exists\n",
212 			      __func__);
213 		return 0;
214 	}
215 
216 	if (snd_ivtv_init(v4l2_dev)) {
217 		IVTV_ALSA_ERR("%s: failed to create struct snd_ivtv_card\n",
218 			      __func__);
219 	} else {
220 		IVTV_DEBUG_ALSA_INFO("created ivtv ALSA interface instance\n");
221 	}
222 	return 0;
223 }
224 
225 static int __init ivtv_alsa_init(void)
226 {
227 	pr_info("ivtv-alsa: module loading...\n");
228 	ivtv_ext_init = &ivtv_alsa_load;
229 	return 0;
230 }
231 
232 static void __exit snd_ivtv_exit(struct snd_ivtv_card *itvsc)
233 {
234 	struct ivtv *itv = to_ivtv(itvsc->v4l2_dev);
235 
236 	/* FIXME - pointer checks & shutdown itvsc */
237 
238 	snd_card_free(itvsc->sc);
239 	itv->alsa = NULL;
240 }
241 
242 static int __exit ivtv_alsa_exit_callback(struct device *dev, void *data)
243 {
244 	struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
245 	struct snd_ivtv_card *itvsc;
246 
247 	if (v4l2_dev == NULL) {
248 		pr_err("ivtv-alsa: %s: struct v4l2_device * is NULL\n",
249 		       __func__);
250 		return 0;
251 	}
252 
253 	itvsc = to_snd_ivtv_card(v4l2_dev);
254 	if (itvsc == NULL) {
255 		IVTV_ALSA_WARN("%s: struct snd_ivtv_card * is NULL\n",
256 			       __func__);
257 		return 0;
258 	}
259 
260 	snd_ivtv_exit(itvsc);
261 	return 0;
262 }
263 
264 static void __exit ivtv_alsa_exit(void)
265 {
266 	struct device_driver *drv;
267 	int ret;
268 
269 	pr_info("ivtv-alsa: module unloading...\n");
270 
271 	drv = driver_find("ivtv", &pci_bus_type);
272 	ret = driver_for_each_device(drv, NULL, NULL, ivtv_alsa_exit_callback);
273 	(void)ret;	/* suppress compiler warning */
274 
275 	ivtv_ext_init = NULL;
276 	pr_info("ivtv-alsa: module unload complete\n");
277 }
278 
279 module_init(ivtv_alsa_init);
280 module_exit(ivtv_alsa_exit);
281