1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  ALSA interface to cx18 PCM capture streams
4 *
5 *  Copyright (C) 2009  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.
9 */
10
11#include <linux/init.h>
12#include <linux/slab.h>
13#include <linux/module.h>
14#include <linux/kernel.h>
15#include <linux/device.h>
16#include <linux/spinlock.h>
17
18#include <media/v4l2-device.h>
19
20#include <sound/core.h>
21#include <sound/initval.h>
22
23#include "cx18-driver.h"
24#include "cx18-version.h"
25#include "cx18-alsa.h"
26#include "cx18-alsa-pcm.h"
27
28int cx18_alsa_debug;
29
30#define CX18_DEBUG_ALSA_INFO(fmt, arg...) \
31	do { \
32		if (cx18_alsa_debug & 2) \
33			printk(KERN_INFO "%s: " fmt, "cx18-alsa", ## arg); \
34	} while (0);
35
36module_param_named(debug, cx18_alsa_debug, int, 0644);
37MODULE_PARM_DESC(debug,
38		 "Debug level (bitmask). Default: 0\n"
39		 "\t\t\t  1/0x0001: warning\n"
40		 "\t\t\t  2/0x0002: info\n");
41
42MODULE_AUTHOR("Andy Walls");
43MODULE_DESCRIPTION("CX23418 ALSA Interface");
44MODULE_SUPPORTED_DEVICE("CX23418 MPEG2 encoder");
45MODULE_LICENSE("GPL");
46
47MODULE_VERSION(CX18_VERSION);
48
49static inline
50struct snd_cx18_card *to_snd_cx18_card(struct v4l2_device *v4l2_dev)
51{
52	return to_cx18(v4l2_dev)->alsa;
53}
54
55static inline
56struct snd_cx18_card *p_to_snd_cx18_card(struct v4l2_device **v4l2_dev)
57{
58	return container_of(v4l2_dev, struct snd_cx18_card, v4l2_dev);
59}
60
61static void snd_cx18_card_free(struct snd_cx18_card *cxsc)
62{
63	if (cxsc == NULL)
64		return;
65
66	if (cxsc->v4l2_dev != NULL)
67		to_cx18(cxsc->v4l2_dev)->alsa = NULL;
68
69	/* FIXME - take any other stopping actions needed */
70
71	kfree(cxsc);
72}
73
74static void snd_cx18_card_private_free(struct snd_card *sc)
75{
76	if (sc == NULL)
77		return;
78	snd_cx18_card_free(sc->private_data);
79	sc->private_data = NULL;
80	sc->private_free = NULL;
81}
82
83static int snd_cx18_card_create(struct v4l2_device *v4l2_dev,
84				       struct snd_card *sc,
85				       struct snd_cx18_card **cxsc)
86{
87	*cxsc = kzalloc(sizeof(struct snd_cx18_card), GFP_KERNEL);
88	if (*cxsc == NULL)
89		return -ENOMEM;
90
91	(*cxsc)->v4l2_dev = v4l2_dev;
92	(*cxsc)->sc = sc;
93
94	sc->private_data = *cxsc;
95	sc->private_free = snd_cx18_card_private_free;
96
97	return 0;
98}
99
100static int snd_cx18_card_set_names(struct snd_cx18_card *cxsc)
101{
102	struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
103	struct snd_card *sc = cxsc->sc;
104
105	/* sc->driver is used by alsa-lib's configurator: simple, unique */
106	strscpy(sc->driver, "CX23418", sizeof(sc->driver));
107
108	/* sc->shortname is a symlink in /proc/asound: CX18-M -> cardN */
109	snprintf(sc->shortname,  sizeof(sc->shortname), "CX18-%d",
110		 cx->instance);
111
112	/* sc->longname is read from /proc/asound/cards */
113	snprintf(sc->longname, sizeof(sc->longname),
114		 "CX23418 #%d %s TV/FM Radio/Line-In Capture",
115		 cx->instance, cx->card_name);
116
117	return 0;
118}
119
120static int snd_cx18_init(struct v4l2_device *v4l2_dev)
121{
122	struct cx18 *cx = to_cx18(v4l2_dev);
123	struct snd_card *sc = NULL;
124	struct snd_cx18_card *cxsc;
125	int ret;
126
127	/* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */
128
129	/* (1) Check and increment the device index */
130	/* This is a no-op for us.  We'll use the cx->instance */
131
132	/* (2) Create a card instance */
133	ret = snd_card_new(&cx->pci_dev->dev,
134			   SNDRV_DEFAULT_IDX1, /* use first available id */
135			   SNDRV_DEFAULT_STR1, /* xid from end of shortname*/
136			   THIS_MODULE, 0, &sc);
137	if (ret) {
138		CX18_ALSA_ERR("%s: snd_card_new() failed with err %d\n",
139			      __func__, ret);
140		goto err_exit;
141	}
142
143	/* (3) Create a main component */
144	ret = snd_cx18_card_create(v4l2_dev, sc, &cxsc);
145	if (ret) {
146		CX18_ALSA_ERR("%s: snd_cx18_card_create() failed with err %d\n",
147			      __func__, ret);
148		goto err_exit_free;
149	}
150
151	/* (4) Set the driver ID and name strings */
152	snd_cx18_card_set_names(cxsc);
153
154
155	ret = snd_cx18_pcm_create(cxsc);
156	if (ret) {
157		CX18_ALSA_ERR("%s: snd_cx18_pcm_create() failed with err %d\n",
158			      __func__, ret);
159		goto err_exit_free;
160	}
161	/* FIXME - proc files */
162
163	/* (7) Set the driver data and return 0 */
164	/* We do this out of normal order for PCI drivers to avoid races */
165	cx->alsa = cxsc;
166
167	/* (6) Register the card instance */
168	ret = snd_card_register(sc);
169	if (ret) {
170		cx->alsa = NULL;
171		CX18_ALSA_ERR("%s: snd_card_register() failed with err %d\n",
172			      __func__, ret);
173		goto err_exit_free;
174	}
175
176	return 0;
177
178err_exit_free:
179	if (sc != NULL)
180		snd_card_free(sc);
181	kfree(cxsc);
182err_exit:
183	return ret;
184}
185
186static int cx18_alsa_load(struct cx18 *cx)
187{
188	struct v4l2_device *v4l2_dev = &cx->v4l2_dev;
189	struct cx18_stream *s;
190
191	if (v4l2_dev == NULL) {
192		printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
193		       __func__);
194		return 0;
195	}
196
197	cx = to_cx18(v4l2_dev);
198	if (cx == NULL) {
199		printk(KERN_ERR "cx18-alsa cx is NULL\n");
200		return 0;
201	}
202
203	s = &cx->streams[CX18_ENC_STREAM_TYPE_PCM];
204	if (s->video_dev.v4l2_dev == NULL) {
205		CX18_DEBUG_ALSA_INFO("%s: PCM stream for card is disabled - skipping\n",
206				     __func__);
207		return 0;
208	}
209
210	if (cx->alsa != NULL) {
211		CX18_ALSA_ERR("%s: struct snd_cx18_card * already exists\n",
212			      __func__);
213		return 0;
214	}
215
216	if (snd_cx18_init(v4l2_dev)) {
217		CX18_ALSA_ERR("%s: failed to create struct snd_cx18_card\n",
218			      __func__);
219	} else {
220		CX18_DEBUG_ALSA_INFO("%s: created cx18 ALSA interface instance\n",
221				     __func__);
222	}
223	return 0;
224}
225
226static int __init cx18_alsa_init(void)
227{
228	printk(KERN_INFO "cx18-alsa: module loading...\n");
229	cx18_ext_init = &cx18_alsa_load;
230	return 0;
231}
232
233static void __exit snd_cx18_exit(struct snd_cx18_card *cxsc)
234{
235	struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
236
237	/* FIXME - pointer checks & shutdown cxsc */
238
239	snd_card_free(cxsc->sc);
240	cx->alsa = NULL;
241}
242
243static int __exit cx18_alsa_exit_callback(struct device *dev, void *data)
244{
245	struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
246	struct snd_cx18_card *cxsc;
247
248	if (v4l2_dev == NULL) {
249		printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
250		       __func__);
251		return 0;
252	}
253
254	cxsc = to_snd_cx18_card(v4l2_dev);
255	if (cxsc == NULL) {
256		CX18_ALSA_WARN("%s: struct snd_cx18_card * is NULL\n",
257			       __func__);
258		return 0;
259	}
260
261	snd_cx18_exit(cxsc);
262	return 0;
263}
264
265static void __exit cx18_alsa_exit(void)
266{
267	struct device_driver *drv;
268	int ret;
269
270	printk(KERN_INFO "cx18-alsa: module unloading...\n");
271
272	drv = driver_find("cx18", &pci_bus_type);
273	ret = driver_for_each_device(drv, NULL, NULL, cx18_alsa_exit_callback);
274	(void)ret;	/* suppress compiler warning */
275
276	cx18_ext_init = NULL;
277	printk(KERN_INFO "cx18-alsa: module unload complete\n");
278}
279
280module_init(cx18_alsa_init);
281module_exit(cx18_alsa_exit);
282