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 43 int 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 51 module_param_named(debug, cx18_alsa_debug, int, 0644); 52 MODULE_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 57 MODULE_AUTHOR("Andy Walls"); 58 MODULE_DESCRIPTION("CX23418 ALSA Interface"); 59 MODULE_SUPPORTED_DEVICE("CX23418 MPEG2 encoder"); 60 MODULE_LICENSE("GPL"); 61 62 MODULE_VERSION(CX18_VERSION); 63 64 static inline 65 struct snd_cx18_card *to_snd_cx18_card(struct v4l2_device *v4l2_dev) 66 { 67 return to_cx18(v4l2_dev)->alsa; 68 } 69 70 static inline 71 struct 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 76 static 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 89 static 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 98 static 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 } 114 115 static 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 } 134 135 static 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; 192 193 err_exit_free: 194 if (sc != NULL) 195 snd_card_free(sc); 196 kfree(cxsc); 197 err_exit: 198 return ret; 199 } 200 201 static 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 - skipping\n", 221 __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\n", 236 __func__); 237 } 238 return 0; 239 } 240 241 static 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 } 247 248 static 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 } 257 258 static 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 } 279 280 static 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 } 294 295 module_init(cx18_alsa_init); 296 module_exit(cx18_alsa_exit); 297