1/*
2 *  ALSA interface to cx18 PCM capture streams
3 *
4 *  Copyright (C) 2009  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.
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 "cx18-driver.h"
38#include "cx18-version.h"
39#include "cx18-alsa.h"
40#include "cx18-alsa-mixer.h"
41#include "cx18-alsa-pcm.h"
42
43int cx18_alsa_debug;
44
45#define CX18_DEBUG_ALSA_INFO(fmt, arg...) \
46	do { \
47		if (cx18_alsa_debug & 2) \
48			printk(KERN_INFO "%s: " fmt, "cx18-alsa", ## arg); \
49	} while (0);
50
51module_param_named(debug, cx18_alsa_debug, int, 0644);
52MODULE_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
57MODULE_AUTHOR("Andy Walls");
58MODULE_DESCRIPTION("CX23418 ALSA Interface");
59MODULE_SUPPORTED_DEVICE("CX23418 MPEG2 encoder");
60MODULE_LICENSE("GPL");
61
62MODULE_VERSION(CX18_VERSION);
63
64static inline
65struct snd_cx18_card *to_snd_cx18_card(struct v4l2_device *v4l2_dev)
66{
67	return to_cx18(v4l2_dev)->alsa;
68}
69
70static inline
71struct snd_cx18_card *p_to_snd_cx18_card(struct v4l2_device **v4l2_dev)
72{
73	return container_of(v4l2_dev, struct snd_cx18_card, v4l2_dev);
74}
75
76static void snd_cx18_card_free(struct snd_cx18_card *cxsc)
77{
78	if (cxsc == NULL)
79		return;
80
81	if (cxsc->v4l2_dev != NULL)
82		to_cx18(cxsc->v4l2_dev)->alsa = NULL;
83
84	/* FIXME - take any other stopping actions needed */
85
86	kfree(cxsc);
87}
88
89static void snd_cx18_card_private_free(struct snd_card *sc)
90{
91	if (sc == NULL)
92		return;
93	snd_cx18_card_free(sc->private_data);
94	sc->private_data = NULL;
95	sc->private_free = NULL;
96}
97
98static int snd_cx18_card_create(struct v4l2_device *v4l2_dev,
99				       struct snd_card *sc,
100				       struct snd_cx18_card **cxsc)
101{
102	*cxsc = kzalloc(sizeof(struct snd_cx18_card), GFP_KERNEL);
103	if (*cxsc == NULL)
104		return -ENOMEM;
105
106	(*cxsc)->v4l2_dev = v4l2_dev;
107	(*cxsc)->sc = sc;
108
109	sc->private_data = *cxsc;
110	sc->private_free = snd_cx18_card_private_free;
111
112	return 0;
113}
114
115static int snd_cx18_card_set_names(struct snd_cx18_card *cxsc)
116{
117	struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
118	struct snd_card *sc = cxsc->sc;
119
120	/* sc->driver is used by alsa-lib's configurator: simple, unique */
121	strlcpy(sc->driver, "CX23418", sizeof(sc->driver));
122
123	/* sc->shortname is a symlink in /proc/asound: CX18-M -> cardN */
124	snprintf(sc->shortname,  sizeof(sc->shortname), "CX18-%d",
125		 cx->instance);
126
127	/* sc->longname is read from /proc/asound/cards */
128	snprintf(sc->longname, sizeof(sc->longname),
129		 "CX23418 #%d %s TV/FM Radio/Line-In Capture",
130		 cx->instance, cx->card_name);
131
132	return 0;
133}
134
135static int snd_cx18_init(struct v4l2_device *v4l2_dev)
136{
137	struct cx18 *cx = to_cx18(v4l2_dev);
138	struct snd_card *sc = NULL;
139	struct snd_cx18_card *cxsc;
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 cx->instance */
146
147	/* (2) Create a card instance */
148	ret = snd_card_new(&cx->pci_dev->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		CX18_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_cx18_card_create(v4l2_dev, sc, &cxsc);
160	if (ret) {
161		CX18_ALSA_ERR("%s: snd_cx18_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_cx18_card_set_names(cxsc);
168
169
170	ret = snd_cx18_pcm_create(cxsc);
171	if (ret) {
172		CX18_ALSA_ERR("%s: snd_cx18_pcm_create() failed with err %d\n",
173			      __func__, ret);
174		goto err_exit_free;
175	}
176	/* FIXME - proc files */
177
178	/* (7) Set the driver data and return 0 */
179	/* We do this out of normal order for PCI drivers to avoid races */
180	cx->alsa = cxsc;
181
182	/* (6) Register the card instance */
183	ret = snd_card_register(sc);
184	if (ret) {
185		cx->alsa = NULL;
186		CX18_ALSA_ERR("%s: snd_card_register() failed with err %d\n",
187			      __func__, ret);
188		goto err_exit_free;
189	}
190
191	return 0;
192
193err_exit_free:
194	if (sc != NULL)
195		snd_card_free(sc);
196	kfree(cxsc);
197err_exit:
198	return ret;
199}
200
201static int cx18_alsa_load(struct cx18 *cx)
202{
203	struct v4l2_device *v4l2_dev = &cx->v4l2_dev;
204	struct cx18_stream *s;
205
206	if (v4l2_dev == NULL) {
207		printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
208		       __func__);
209		return 0;
210	}
211
212	cx = to_cx18(v4l2_dev);
213	if (cx == NULL) {
214		printk(KERN_ERR "cx18-alsa cx is NULL\n");
215		return 0;
216	}
217
218	s = &cx->streams[CX18_ENC_STREAM_TYPE_PCM];
219	if (s->video_dev.v4l2_dev == NULL) {
220		CX18_DEBUG_ALSA_INFO("%s: PCM stream for card is disabled - "
221				     "skipping\n", __func__);
222		return 0;
223	}
224
225	if (cx->alsa != NULL) {
226		CX18_ALSA_ERR("%s: struct snd_cx18_card * already exists\n",
227			      __func__);
228		return 0;
229	}
230
231	if (snd_cx18_init(v4l2_dev)) {
232		CX18_ALSA_ERR("%s: failed to create struct snd_cx18_card\n",
233			      __func__);
234	} else {
235		CX18_DEBUG_ALSA_INFO("%s: created cx18 ALSA interface instance "
236				     "\n", __func__);
237	}
238	return 0;
239}
240
241static int __init cx18_alsa_init(void)
242{
243	printk(KERN_INFO "cx18-alsa: module loading...\n");
244	cx18_ext_init = &cx18_alsa_load;
245	return 0;
246}
247
248static void __exit snd_cx18_exit(struct snd_cx18_card *cxsc)
249{
250	struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
251
252	/* FIXME - pointer checks & shutdown cxsc */
253
254	snd_card_free(cxsc->sc);
255	cx->alsa = NULL;
256}
257
258static int __exit cx18_alsa_exit_callback(struct device *dev, void *data)
259{
260	struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
261	struct snd_cx18_card *cxsc;
262
263	if (v4l2_dev == NULL) {
264		printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
265		       __func__);
266		return 0;
267	}
268
269	cxsc = to_snd_cx18_card(v4l2_dev);
270	if (cxsc == NULL) {
271		CX18_ALSA_WARN("%s: struct snd_cx18_card * is NULL\n",
272			       __func__);
273		return 0;
274	}
275
276	snd_cx18_exit(cxsc);
277	return 0;
278}
279
280static void __exit cx18_alsa_exit(void)
281{
282	struct device_driver *drv;
283	int ret;
284
285	printk(KERN_INFO "cx18-alsa: module unloading...\n");
286
287	drv = driver_find("cx18", &pci_bus_type);
288	ret = driver_for_each_device(drv, NULL, NULL, cx18_alsa_exit_callback);
289	(void)ret;	/* suppress compiler warning */
290
291	cx18_ext_init = NULL;
292	printk(KERN_INFO "cx18-alsa: module unload complete\n");
293}
294
295module_init(cx18_alsa_init);
296module_exit(cx18_alsa_exit);
297