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 20 #include <linux/init.h> 21 #include <linux/slab.h> 22 #include <linux/module.h> 23 #include <linux/kernel.h> 24 #include <linux/device.h> 25 #include <linux/spinlock.h> 26 27 #include <media/v4l2-device.h> 28 29 #include <sound/core.h> 30 #include <sound/initval.h> 31 32 #include "cx18-driver.h" 33 #include "cx18-version.h" 34 #include "cx18-alsa.h" 35 #include "cx18-alsa-mixer.h" 36 #include "cx18-alsa-pcm.h" 37 38 int cx18_alsa_debug; 39 40 #define CX18_DEBUG_ALSA_INFO(fmt, arg...) \ 41 do { \ 42 if (cx18_alsa_debug & 2) \ 43 printk(KERN_INFO "%s: " fmt, "cx18-alsa", ## arg); \ 44 } while (0); 45 46 module_param_named(debug, cx18_alsa_debug, int, 0644); 47 MODULE_PARM_DESC(debug, 48 "Debug level (bitmask). Default: 0\n" 49 "\t\t\t 1/0x0001: warning\n" 50 "\t\t\t 2/0x0002: info\n"); 51 52 MODULE_AUTHOR("Andy Walls"); 53 MODULE_DESCRIPTION("CX23418 ALSA Interface"); 54 MODULE_SUPPORTED_DEVICE("CX23418 MPEG2 encoder"); 55 MODULE_LICENSE("GPL"); 56 57 MODULE_VERSION(CX18_VERSION); 58 59 static inline 60 struct snd_cx18_card *to_snd_cx18_card(struct v4l2_device *v4l2_dev) 61 { 62 return to_cx18(v4l2_dev)->alsa; 63 } 64 65 static inline 66 struct snd_cx18_card *p_to_snd_cx18_card(struct v4l2_device **v4l2_dev) 67 { 68 return container_of(v4l2_dev, struct snd_cx18_card, v4l2_dev); 69 } 70 71 static void snd_cx18_card_free(struct snd_cx18_card *cxsc) 72 { 73 if (cxsc == NULL) 74 return; 75 76 if (cxsc->v4l2_dev != NULL) 77 to_cx18(cxsc->v4l2_dev)->alsa = NULL; 78 79 /* FIXME - take any other stopping actions needed */ 80 81 kfree(cxsc); 82 } 83 84 static void snd_cx18_card_private_free(struct snd_card *sc) 85 { 86 if (sc == NULL) 87 return; 88 snd_cx18_card_free(sc->private_data); 89 sc->private_data = NULL; 90 sc->private_free = NULL; 91 } 92 93 static int snd_cx18_card_create(struct v4l2_device *v4l2_dev, 94 struct snd_card *sc, 95 struct snd_cx18_card **cxsc) 96 { 97 *cxsc = kzalloc(sizeof(struct snd_cx18_card), GFP_KERNEL); 98 if (*cxsc == NULL) 99 return -ENOMEM; 100 101 (*cxsc)->v4l2_dev = v4l2_dev; 102 (*cxsc)->sc = sc; 103 104 sc->private_data = *cxsc; 105 sc->private_free = snd_cx18_card_private_free; 106 107 return 0; 108 } 109 110 static int snd_cx18_card_set_names(struct snd_cx18_card *cxsc) 111 { 112 struct cx18 *cx = to_cx18(cxsc->v4l2_dev); 113 struct snd_card *sc = cxsc->sc; 114 115 /* sc->driver is used by alsa-lib's configurator: simple, unique */ 116 strlcpy(sc->driver, "CX23418", sizeof(sc->driver)); 117 118 /* sc->shortname is a symlink in /proc/asound: CX18-M -> cardN */ 119 snprintf(sc->shortname, sizeof(sc->shortname), "CX18-%d", 120 cx->instance); 121 122 /* sc->longname is read from /proc/asound/cards */ 123 snprintf(sc->longname, sizeof(sc->longname), 124 "CX23418 #%d %s TV/FM Radio/Line-In Capture", 125 cx->instance, cx->card_name); 126 127 return 0; 128 } 129 130 static int snd_cx18_init(struct v4l2_device *v4l2_dev) 131 { 132 struct cx18 *cx = to_cx18(v4l2_dev); 133 struct snd_card *sc = NULL; 134 struct snd_cx18_card *cxsc; 135 int ret; 136 137 /* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */ 138 139 /* (1) Check and increment the device index */ 140 /* This is a no-op for us. We'll use the cx->instance */ 141 142 /* (2) Create a card instance */ 143 ret = snd_card_new(&cx->pci_dev->dev, 144 SNDRV_DEFAULT_IDX1, /* use first available id */ 145 SNDRV_DEFAULT_STR1, /* xid from end of shortname*/ 146 THIS_MODULE, 0, &sc); 147 if (ret) { 148 CX18_ALSA_ERR("%s: snd_card_new() failed with err %d\n", 149 __func__, ret); 150 goto err_exit; 151 } 152 153 /* (3) Create a main component */ 154 ret = snd_cx18_card_create(v4l2_dev, sc, &cxsc); 155 if (ret) { 156 CX18_ALSA_ERR("%s: snd_cx18_card_create() failed with err %d\n", 157 __func__, ret); 158 goto err_exit_free; 159 } 160 161 /* (4) Set the driver ID and name strings */ 162 snd_cx18_card_set_names(cxsc); 163 164 165 ret = snd_cx18_pcm_create(cxsc); 166 if (ret) { 167 CX18_ALSA_ERR("%s: snd_cx18_pcm_create() failed with err %d\n", 168 __func__, ret); 169 goto err_exit_free; 170 } 171 /* FIXME - proc files */ 172 173 /* (7) Set the driver data and return 0 */ 174 /* We do this out of normal order for PCI drivers to avoid races */ 175 cx->alsa = cxsc; 176 177 /* (6) Register the card instance */ 178 ret = snd_card_register(sc); 179 if (ret) { 180 cx->alsa = NULL; 181 CX18_ALSA_ERR("%s: snd_card_register() failed with err %d\n", 182 __func__, ret); 183 goto err_exit_free; 184 } 185 186 return 0; 187 188 err_exit_free: 189 if (sc != NULL) 190 snd_card_free(sc); 191 kfree(cxsc); 192 err_exit: 193 return ret; 194 } 195 196 static int cx18_alsa_load(struct cx18 *cx) 197 { 198 struct v4l2_device *v4l2_dev = &cx->v4l2_dev; 199 struct cx18_stream *s; 200 201 if (v4l2_dev == NULL) { 202 printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n", 203 __func__); 204 return 0; 205 } 206 207 cx = to_cx18(v4l2_dev); 208 if (cx == NULL) { 209 printk(KERN_ERR "cx18-alsa cx is NULL\n"); 210 return 0; 211 } 212 213 s = &cx->streams[CX18_ENC_STREAM_TYPE_PCM]; 214 if (s->video_dev.v4l2_dev == NULL) { 215 CX18_DEBUG_ALSA_INFO("%s: PCM stream for card is disabled - skipping\n", 216 __func__); 217 return 0; 218 } 219 220 if (cx->alsa != NULL) { 221 CX18_ALSA_ERR("%s: struct snd_cx18_card * already exists\n", 222 __func__); 223 return 0; 224 } 225 226 if (snd_cx18_init(v4l2_dev)) { 227 CX18_ALSA_ERR("%s: failed to create struct snd_cx18_card\n", 228 __func__); 229 } else { 230 CX18_DEBUG_ALSA_INFO("%s: created cx18 ALSA interface instance\n", 231 __func__); 232 } 233 return 0; 234 } 235 236 static int __init cx18_alsa_init(void) 237 { 238 printk(KERN_INFO "cx18-alsa: module loading...\n"); 239 cx18_ext_init = &cx18_alsa_load; 240 return 0; 241 } 242 243 static void __exit snd_cx18_exit(struct snd_cx18_card *cxsc) 244 { 245 struct cx18 *cx = to_cx18(cxsc->v4l2_dev); 246 247 /* FIXME - pointer checks & shutdown cxsc */ 248 249 snd_card_free(cxsc->sc); 250 cx->alsa = NULL; 251 } 252 253 static int __exit cx18_alsa_exit_callback(struct device *dev, void *data) 254 { 255 struct v4l2_device *v4l2_dev = dev_get_drvdata(dev); 256 struct snd_cx18_card *cxsc; 257 258 if (v4l2_dev == NULL) { 259 printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n", 260 __func__); 261 return 0; 262 } 263 264 cxsc = to_snd_cx18_card(v4l2_dev); 265 if (cxsc == NULL) { 266 CX18_ALSA_WARN("%s: struct snd_cx18_card * is NULL\n", 267 __func__); 268 return 0; 269 } 270 271 snd_cx18_exit(cxsc); 272 return 0; 273 } 274 275 static void __exit cx18_alsa_exit(void) 276 { 277 struct device_driver *drv; 278 int ret; 279 280 printk(KERN_INFO "cx18-alsa: module unloading...\n"); 281 282 drv = driver_find("cx18", &pci_bus_type); 283 ret = driver_for_each_device(drv, NULL, NULL, cx18_alsa_exit_callback); 284 (void)ret; /* suppress compiler warning */ 285 286 cx18_ext_init = NULL; 287 printk(KERN_INFO "cx18-alsa: module unload complete\n"); 288 } 289 290 module_init(cx18_alsa_init); 291 module_exit(cx18_alsa_exit); 292