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 inline 55 struct snd_cx18_card *p_to_snd_cx18_card(struct v4l2_device **v4l2_dev) 56 { 57 return container_of(v4l2_dev, struct snd_cx18_card, v4l2_dev); 58 } 59 60 static void snd_cx18_card_free(struct snd_cx18_card *cxsc) 61 { 62 if (cxsc == NULL) 63 return; 64 65 if (cxsc->v4l2_dev != NULL) 66 to_cx18(cxsc->v4l2_dev)->alsa = NULL; 67 68 /* FIXME - take any other stopping actions needed */ 69 70 kfree(cxsc); 71 } 72 73 static void snd_cx18_card_private_free(struct snd_card *sc) 74 { 75 if (sc == NULL) 76 return; 77 snd_cx18_card_free(sc->private_data); 78 sc->private_data = NULL; 79 sc->private_free = NULL; 80 } 81 82 static int snd_cx18_card_create(struct v4l2_device *v4l2_dev, 83 struct snd_card *sc, 84 struct snd_cx18_card **cxsc) 85 { 86 *cxsc = kzalloc(sizeof(struct snd_cx18_card), GFP_KERNEL); 87 if (*cxsc == NULL) 88 return -ENOMEM; 89 90 (*cxsc)->v4l2_dev = v4l2_dev; 91 (*cxsc)->sc = sc; 92 93 sc->private_data = *cxsc; 94 sc->private_free = snd_cx18_card_private_free; 95 96 return 0; 97 } 98 99 static int snd_cx18_card_set_names(struct snd_cx18_card *cxsc) 100 { 101 struct cx18 *cx = to_cx18(cxsc->v4l2_dev); 102 struct snd_card *sc = cxsc->sc; 103 104 /* sc->driver is used by alsa-lib's configurator: simple, unique */ 105 strscpy(sc->driver, "CX23418", sizeof(sc->driver)); 106 107 /* sc->shortname is a symlink in /proc/asound: CX18-M -> cardN */ 108 snprintf(sc->shortname, sizeof(sc->shortname), "CX18-%d", 109 cx->instance); 110 111 /* sc->longname is read from /proc/asound/cards */ 112 snprintf(sc->longname, sizeof(sc->longname), 113 "CX23418 #%d %s TV/FM Radio/Line-In Capture", 114 cx->instance, cx->card_name); 115 116 return 0; 117 } 118 119 static int snd_cx18_init(struct v4l2_device *v4l2_dev) 120 { 121 struct cx18 *cx = to_cx18(v4l2_dev); 122 struct snd_card *sc = NULL; 123 struct snd_cx18_card *cxsc; 124 int ret; 125 126 /* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */ 127 128 /* (1) Check and increment the device index */ 129 /* This is a no-op for us. We'll use the cx->instance */ 130 131 /* (2) Create a card instance */ 132 ret = snd_card_new(&cx->pci_dev->dev, 133 SNDRV_DEFAULT_IDX1, /* use first available id */ 134 SNDRV_DEFAULT_STR1, /* xid from end of shortname*/ 135 THIS_MODULE, 0, &sc); 136 if (ret) { 137 CX18_ALSA_ERR("%s: snd_card_new() failed with err %d\n", 138 __func__, ret); 139 goto err_exit; 140 } 141 142 /* (3) Create a main component */ 143 ret = snd_cx18_card_create(v4l2_dev, sc, &cxsc); 144 if (ret) { 145 CX18_ALSA_ERR("%s: snd_cx18_card_create() failed with err %d\n", 146 __func__, ret); 147 goto err_exit_free; 148 } 149 150 /* (4) Set the driver ID and name strings */ 151 snd_cx18_card_set_names(cxsc); 152 153 154 ret = snd_cx18_pcm_create(cxsc); 155 if (ret) { 156 CX18_ALSA_ERR("%s: snd_cx18_pcm_create() failed with err %d\n", 157 __func__, ret); 158 goto err_exit_free; 159 } 160 /* FIXME - proc files */ 161 162 /* (7) Set the driver data and return 0 */ 163 /* We do this out of normal order for PCI drivers to avoid races */ 164 cx->alsa = cxsc; 165 166 /* (6) Register the card instance */ 167 ret = snd_card_register(sc); 168 if (ret) { 169 cx->alsa = NULL; 170 CX18_ALSA_ERR("%s: snd_card_register() failed with err %d\n", 171 __func__, ret); 172 goto err_exit_free; 173 } 174 175 return 0; 176 177 err_exit_free: 178 if (sc != NULL) 179 snd_card_free(sc); 180 kfree(cxsc); 181 err_exit: 182 return ret; 183 } 184 185 static int cx18_alsa_load(struct cx18 *cx) 186 { 187 struct v4l2_device *v4l2_dev = &cx->v4l2_dev; 188 struct cx18_stream *s; 189 190 if (v4l2_dev == NULL) { 191 printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n", 192 __func__); 193 return 0; 194 } 195 196 cx = to_cx18(v4l2_dev); 197 if (cx == NULL) { 198 printk(KERN_ERR "cx18-alsa cx is NULL\n"); 199 return 0; 200 } 201 202 s = &cx->streams[CX18_ENC_STREAM_TYPE_PCM]; 203 if (s->video_dev.v4l2_dev == NULL) { 204 CX18_DEBUG_ALSA_INFO("%s: PCM stream for card is disabled - skipping\n", 205 __func__); 206 return 0; 207 } 208 209 if (cx->alsa != NULL) { 210 CX18_ALSA_ERR("%s: struct snd_cx18_card * already exists\n", 211 __func__); 212 return 0; 213 } 214 215 if (snd_cx18_init(v4l2_dev)) { 216 CX18_ALSA_ERR("%s: failed to create struct snd_cx18_card\n", 217 __func__); 218 } else { 219 CX18_DEBUG_ALSA_INFO("%s: created cx18 ALSA interface instance\n", 220 __func__); 221 } 222 return 0; 223 } 224 225 static int __init cx18_alsa_init(void) 226 { 227 printk(KERN_INFO "cx18-alsa: module loading...\n"); 228 cx18_ext_init = &cx18_alsa_load; 229 return 0; 230 } 231 232 static void __exit snd_cx18_exit(struct snd_cx18_card *cxsc) 233 { 234 struct cx18 *cx = to_cx18(cxsc->v4l2_dev); 235 236 /* FIXME - pointer checks & shutdown cxsc */ 237 238 snd_card_free(cxsc->sc); 239 cx->alsa = NULL; 240 } 241 242 static int __exit cx18_alsa_exit_callback(struct device *dev, void *data) 243 { 244 struct v4l2_device *v4l2_dev = dev_get_drvdata(dev); 245 struct snd_cx18_card *cxsc; 246 247 if (v4l2_dev == NULL) { 248 printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n", 249 __func__); 250 return 0; 251 } 252 253 cxsc = to_snd_cx18_card(v4l2_dev); 254 if (cxsc == NULL) { 255 CX18_ALSA_WARN("%s: struct snd_cx18_card * is NULL\n", 256 __func__); 257 return 0; 258 } 259 260 snd_cx18_exit(cxsc); 261 return 0; 262 } 263 264 static void __exit cx18_alsa_exit(void) 265 { 266 struct device_driver *drv; 267 int ret; 268 269 printk(KERN_INFO "cx18-alsa: module unloading...\n"); 270 271 drv = driver_find("cx18", &pci_bus_type); 272 ret = driver_for_each_device(drv, NULL, NULL, cx18_alsa_exit_callback); 273 (void)ret; /* suppress compiler warning */ 274 275 cx18_ext_init = NULL; 276 printk(KERN_INFO "cx18-alsa: module unload complete\n"); 277 } 278 279 module_init(cx18_alsa_init); 280 module_exit(cx18_alsa_exit); 281