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 
28 int 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 
36 module_param_named(debug, cx18_alsa_debug, int, 0644);
37 MODULE_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 
42 MODULE_AUTHOR("Andy Walls");
43 MODULE_DESCRIPTION("CX23418 ALSA Interface");
44 MODULE_LICENSE("GPL");
45 
46 MODULE_VERSION(CX18_VERSION);
47 
48 static inline
49 struct snd_cx18_card *to_snd_cx18_card(struct v4l2_device *v4l2_dev)
50 {
51 	return to_cx18(v4l2_dev)->alsa;
52 }
53 
54 static void snd_cx18_card_free(struct snd_cx18_card *cxsc)
55 {
56 	if (cxsc == NULL)
57 		return;
58 
59 	if (cxsc->v4l2_dev != NULL)
60 		to_cx18(cxsc->v4l2_dev)->alsa = NULL;
61 
62 	/* FIXME - take any other stopping actions needed */
63 
64 	kfree(cxsc);
65 }
66 
67 static void snd_cx18_card_private_free(struct snd_card *sc)
68 {
69 	if (sc == NULL)
70 		return;
71 	snd_cx18_card_free(sc->private_data);
72 	sc->private_data = NULL;
73 	sc->private_free = NULL;
74 }
75 
76 static int snd_cx18_card_create(struct v4l2_device *v4l2_dev,
77 				       struct snd_card *sc,
78 				       struct snd_cx18_card **cxsc)
79 {
80 	*cxsc = kzalloc(sizeof(struct snd_cx18_card), GFP_KERNEL);
81 	if (*cxsc == NULL)
82 		return -ENOMEM;
83 
84 	(*cxsc)->v4l2_dev = v4l2_dev;
85 	(*cxsc)->sc = sc;
86 
87 	sc->private_data = *cxsc;
88 	sc->private_free = snd_cx18_card_private_free;
89 
90 	return 0;
91 }
92 
93 static int snd_cx18_card_set_names(struct snd_cx18_card *cxsc)
94 {
95 	struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
96 	struct snd_card *sc = cxsc->sc;
97 
98 	/* sc->driver is used by alsa-lib's configurator: simple, unique */
99 	strscpy(sc->driver, "CX23418", sizeof(sc->driver));
100 
101 	/* sc->shortname is a symlink in /proc/asound: CX18-M -> cardN */
102 	snprintf(sc->shortname,  sizeof(sc->shortname), "CX18-%d",
103 		 cx->instance);
104 
105 	/* sc->longname is read from /proc/asound/cards */
106 	snprintf(sc->longname, sizeof(sc->longname),
107 		 "CX23418 #%d %s TV/FM Radio/Line-In Capture",
108 		 cx->instance, cx->card_name);
109 
110 	return 0;
111 }
112 
113 static int snd_cx18_init(struct v4l2_device *v4l2_dev)
114 {
115 	struct cx18 *cx = to_cx18(v4l2_dev);
116 	struct snd_card *sc = NULL;
117 	struct snd_cx18_card *cxsc;
118 	int ret;
119 
120 	/* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */
121 
122 	/* (1) Check and increment the device index */
123 	/* This is a no-op for us.  We'll use the cx->instance */
124 
125 	/* (2) Create a card instance */
126 	ret = snd_card_new(&cx->pci_dev->dev,
127 			   SNDRV_DEFAULT_IDX1, /* use first available id */
128 			   SNDRV_DEFAULT_STR1, /* xid from end of shortname*/
129 			   THIS_MODULE, 0, &sc);
130 	if (ret) {
131 		CX18_ALSA_ERR("%s: snd_card_new() failed with err %d\n",
132 			      __func__, ret);
133 		goto err_exit;
134 	}
135 
136 	/* (3) Create a main component */
137 	ret = snd_cx18_card_create(v4l2_dev, sc, &cxsc);
138 	if (ret) {
139 		CX18_ALSA_ERR("%s: snd_cx18_card_create() failed with err %d\n",
140 			      __func__, ret);
141 		goto err_exit_free;
142 	}
143 
144 	/* (4) Set the driver ID and name strings */
145 	snd_cx18_card_set_names(cxsc);
146 
147 
148 	ret = snd_cx18_pcm_create(cxsc);
149 	if (ret) {
150 		CX18_ALSA_ERR("%s: snd_cx18_pcm_create() failed with err %d\n",
151 			      __func__, ret);
152 		goto err_exit_free;
153 	}
154 	/* FIXME - proc files */
155 
156 	/* (7) Set the driver data and return 0 */
157 	/* We do this out of normal order for PCI drivers to avoid races */
158 	cx->alsa = cxsc;
159 
160 	/* (6) Register the card instance */
161 	ret = snd_card_register(sc);
162 	if (ret) {
163 		cx->alsa = NULL;
164 		CX18_ALSA_ERR("%s: snd_card_register() failed with err %d\n",
165 			      __func__, ret);
166 		goto err_exit_free;
167 	}
168 
169 	return 0;
170 
171 err_exit_free:
172 	if (sc != NULL)
173 		snd_card_free(sc);
174 	kfree(cxsc);
175 err_exit:
176 	return ret;
177 }
178 
179 static int cx18_alsa_load(struct cx18 *cx)
180 {
181 	struct v4l2_device *v4l2_dev = &cx->v4l2_dev;
182 	struct cx18_stream *s;
183 
184 	if (v4l2_dev == NULL) {
185 		printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
186 		       __func__);
187 		return 0;
188 	}
189 
190 	cx = to_cx18(v4l2_dev);
191 	if (cx == NULL) {
192 		printk(KERN_ERR "cx18-alsa cx is NULL\n");
193 		return 0;
194 	}
195 
196 	s = &cx->streams[CX18_ENC_STREAM_TYPE_PCM];
197 	if (s->video_dev.v4l2_dev == NULL) {
198 		CX18_DEBUG_ALSA_INFO("%s: PCM stream for card is disabled - skipping\n",
199 				     __func__);
200 		return 0;
201 	}
202 
203 	if (cx->alsa != NULL) {
204 		CX18_ALSA_ERR("%s: struct snd_cx18_card * already exists\n",
205 			      __func__);
206 		return 0;
207 	}
208 
209 	if (snd_cx18_init(v4l2_dev)) {
210 		CX18_ALSA_ERR("%s: failed to create struct snd_cx18_card\n",
211 			      __func__);
212 	} else {
213 		CX18_DEBUG_ALSA_INFO("%s: created cx18 ALSA interface instance\n",
214 				     __func__);
215 	}
216 	return 0;
217 }
218 
219 static int __init cx18_alsa_init(void)
220 {
221 	printk(KERN_INFO "cx18-alsa: module loading...\n");
222 	cx18_ext_init = &cx18_alsa_load;
223 	return 0;
224 }
225 
226 static void __exit snd_cx18_exit(struct snd_cx18_card *cxsc)
227 {
228 	struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
229 
230 	/* FIXME - pointer checks & shutdown cxsc */
231 
232 	snd_card_free(cxsc->sc);
233 	cx->alsa = NULL;
234 }
235 
236 static int __exit cx18_alsa_exit_callback(struct device *dev, void *data)
237 {
238 	struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
239 	struct snd_cx18_card *cxsc;
240 
241 	if (v4l2_dev == NULL) {
242 		printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
243 		       __func__);
244 		return 0;
245 	}
246 
247 	cxsc = to_snd_cx18_card(v4l2_dev);
248 	if (cxsc == NULL) {
249 		CX18_ALSA_WARN("%s: struct snd_cx18_card * is NULL\n",
250 			       __func__);
251 		return 0;
252 	}
253 
254 	snd_cx18_exit(cxsc);
255 	return 0;
256 }
257 
258 static void __exit cx18_alsa_exit(void)
259 {
260 	struct device_driver *drv;
261 	int ret;
262 
263 	printk(KERN_INFO "cx18-alsa: module unloading...\n");
264 
265 	drv = driver_find("cx18", &pci_bus_type);
266 	ret = driver_for_each_device(drv, NULL, NULL, cx18_alsa_exit_callback);
267 	(void)ret;	/* suppress compiler warning */
268 
269 	cx18_ext_init = NULL;
270 	printk(KERN_INFO "cx18-alsa: module unload complete\n");
271 }
272 
273 module_init(cx18_alsa_init);
274 module_exit(cx18_alsa_exit);
275