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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * ALSA interface to cx18 PCM capture streams4 *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 28int 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 36module_param_named(debug, cx18_alsa_debug, int, 0644);37MODULE_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 42MODULE_AUTHOR("Andy Walls");43MODULE_DESCRIPTION("CX23418 ALSA Interface");44MODULE_LICENSE("GPL");45 46MODULE_VERSION(CX18_VERSION);47 48static inline49struct snd_cx18_card *to_snd_cx18_card(struct v4l2_device *v4l2_dev)50{51 return to_cx18(v4l2_dev)->alsa;52}53 54static 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 67static 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 76static 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 93static 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 113static 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 171err_exit_free:172 if (sc != NULL)173 snd_card_free(sc);174 kfree(cxsc);175err_exit:176 return ret;177}178 179static 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 219static 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 226static 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 236static 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 258static 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 273module_init(cx18_alsa_init);274module_exit(cx18_alsa_exit);275