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