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