text: /*
   *  ALSA interface to cx18 PCM capture streams
   *
   *  Copyright (C) 2009  Andy Walls <awalls@md.metrocast.net>
   *  Copyright (C) 2009  Devin Heitmueller <dheitmueller@kernellabs.com>
   *
   *  Portions of this work were sponsored by ONELAN Limited.
   *
   *  This program is free software; you can redistribute it and/or modify
   *  it under the terms of the GNU General Public License as published by
   *  the Free Software Foundation; either version 2 of the License, or
   *  (at your option) any later version.
   *
   *  This program is distributed in the hope that it will be useful,
   *  but WITHOUT ANY WARRANTY; without even the implied warranty of
   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *  GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License
   *  along with this program; if not, write to the Free Software
   *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   *  02111-1307  USA
   */
  
  #include <linux/init.h>
  #include <linux/slab.h>
  #include <linux/module.h>
  #include <linux/kernel.h>
  #include <linux/device.h>
  #include <linux/spinlock.h>
  
  #include <media/v4l2-device.h>
  
  #include <sound/core.h>
  #include <sound/initval.h>
  
  #include "cx18-driver.h"
  #include "cx18-version.h"
  #include "cx18-alsa.h"
  #include "cx18-alsa-mixer.h"
  #include "cx18-alsa-pcm.h"
  
  int cx18_alsa_debug;
  
  #define CX18_DEBUG_ALSA_INFO(fmt, arg...) \
  	do { \
  		if (cx18_alsa_debug & 2) \
  			printk(KERN_INFO "%s: " fmt, "cx18-alsa", ## arg); \
  	} while (0);
  
  module_param_named(debug, cx18_alsa_debug, int, 0644);
  MODULE_PARM_DESC(debug,
  		 "Debug level (bitmask). Default: 0\n"
  		 "\t\t\t  1/0x0001: warning\n"
  		 "\t\t\t  2/0x0002: info\n");
  
  MODULE_AUTHOR("Andy Walls");
  MODULE_DESCRIPTION("CX23418 ALSA Interface");
  MODULE_SUPPORTED_DEVICE("CX23418 MPEG2 encoder");
  MODULE_LICENSE("GPL");
  
  MODULE_VERSION(CX18_VERSION);
  
  static inline
  struct snd_cx18_card *to_snd_cx18_card(struct v4l2_device *v4l2_dev)
  {
  	return to_cx18(v4l2_dev)->alsa;
  }
  
  static inline
  struct snd_cx18_card *p_to_snd_cx18_card(struct v4l2_device **v4l2_dev)
  {
  	return container_of(v4l2_dev, struct snd_cx18_card, v4l2_dev);
  }
  
  static void snd_cx18_card_free(struct snd_cx18_card *cxsc)
  {
  	if (cxsc == NULL)
  		return;
  
  	if (cxsc->v4l2_dev != NULL)
  		to_cx18(cxsc->v4l2_dev)->alsa = NULL;
  
  
  	kfree(cxsc);
  }
  
  static void snd_cx18_card_private_free(struct snd_card *sc)
  {
  	if (sc == NULL)
  		return;
  	snd_cx18_card_free(sc->private_data);
  	sc->private_data = NULL;
  	sc->private_free = NULL;
  }
  
  static int snd_cx18_card_create(struct v4l2_device *v4l2_dev,
  				       struct snd_card *sc,
  				       struct snd_cx18_card **cxsc)
  {
  	*cxsc = kzalloc(sizeof(struct snd_cx18_card), GFP_KERNEL);
  	if (*cxsc == NULL)
  		return -ENOMEM;
  
  	(*cxsc)->v4l2_dev = v4l2_dev;
  	(*cxsc)->sc = sc;
  
  	sc->private_data = *cxsc;
  	sc->private_free = snd_cx18_card_private_free;
  
  	return 0;
  }
  
  static int snd_cx18_card_set_names(struct snd_cx18_card *cxsc)
  {
  	struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
  	struct snd_card *sc = cxsc->sc;
  
  	/* sc->driver is used by alsa-lib's configurator: simple, unique */
  	strlcpy(sc->driver, "CX23418", sizeof(sc->driver));
  
  	/* sc->shortname is a symlink in /proc/asound: CX18-M -> cardN */
  	snprintf(sc->shortname,  sizeof(sc->shortname), "CX18-%d",
  		 cx->instance);
  
  	/* sc->longname is read from /proc/asound/cards */
  	snprintf(sc->longname, sizeof(sc->longname),
  		 "CX23418 #%d %s TV/FM Radio/Line-In Capture",
  		 cx->instance, cx->card_name);
  
  	return 0;
  }
  
  static int snd_cx18_init(struct v4l2_device *v4l2_dev)
  {
  	struct cx18 *cx = to_cx18(v4l2_dev);
  	struct snd_card *sc = NULL;
  	struct snd_cx18_card *cxsc;
  	int ret;
  
  	/* Numbrs steps from "Writing an ALSA Driver" by Takashi Iwai */
  
  	/* (1) Check and increment the device index */
  	/* This is a no-op for us.  We'll use the cx->instance */
  
  	/* (2) Create a card instance */
  	ret = snd_card_create(SNDRV_DEFAULT_IDX1, /* use first available id */
  			      SNDRV_DEFAULT_STR1, /* xid from end of shortname*/
  			      THIS_MODULE, 0, &sc);
  	if (ret) {
  		CX18_ALSA_ERR("%s: snd_card_create() failed with err %d\n",
  			      __func__, ret);
  		goto err_exit;
  	}
  
  	/* (3) Create a main component */
  	ret = snd_cx18_card_create(v4l2_dev, sc, &cxsc);
  	if (ret) {
  		CX18_ALSA_ERR("%s: snd_cx18_card_create() failed with err %d\n",
  			      __func__, ret);
  		goto err_exit_free;
  	}
  
  	/* (4) Set the driver ID and name strings */
  	snd_cx18_card_set_names(cxsc);
  
  
  	ret = snd_cx18_pcm_create(cxsc);
  	if (ret) {
  		CX18_ALSA_ERR("%s: snd_cx18_pcm_create() failed with err %d\n",
  			      __func__, ret);
  		goto err_exit_free;
  	}
  
  	/* (7) Set the driver data and return 0 */
  	/* We do this out of normal order for PCI drivers to avoid races */
  	cx->alsa = cxsc;
  
  	/* (6) Register the card instance */
  	ret = snd_card_register(sc);
  	if (ret) {
  		cx->alsa = NULL;
  		CX18_ALSA_ERR("%s: snd_card_register() failed with err %d\n",
  			      __func__, ret);
  		goto err_exit_free;
  	}
  
  	return 0;
  
  err_exit_free:
  	if (sc != NULL)
  		snd_card_free(sc);
  err_exit:
  	return ret;
  }
  
  int cx18_alsa_load(struct cx18 *cx)
  {
  	struct v4l2_device *v4l2_dev = &cx->v4l2_dev;
  	struct cx18_stream *s;
  
  	if (v4l2_dev == NULL) {
  		printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
  		       __func__);
  		return 0;
  	}
  
  	cx = to_cx18(v4l2_dev);
  	if (cx == NULL) {
  		printk(KERN_ERR "cx18-alsa cx is NULL\n");
  		return 0;
  	}
  
  	s = &cx->streams[CX18_ENC_STREAM_TYPE_PCM];
  	if (s->video_dev == NULL) {
  		CX18_DEBUG_ALSA_INFO("%s: PCM stream for card is disabled - "
  				     "skipping\n", __func__);
  		return 0;
  	}
  
  	if (cx->alsa != NULL) {
  		CX18_ALSA_ERR("%s: struct snd_cx18_card * already exists\n",
  			      __func__);
  		return 0;
  	}
  
  	if (snd_cx18_init(v4l2_dev)) {
  		CX18_ALSA_ERR("%s: failed to create struct snd_cx18_card\n",
  			      __func__);
  	} else {
  		CX18_DEBUG_ALSA_INFO("%s: created cx18 ALSA interface instance "
  				     "\n", __func__);
  	}
  	return 0;
  }
  
  static int __init cx18_alsa_init(void)
  {
  	printk(KERN_INFO "cx18-alsa: module loading...\n");
  	cx18_ext_init = &cx18_alsa_load;
  	return 0;
  }
  
  static void __exit snd_cx18_exit(struct snd_cx18_card *cxsc)
  {
  	struct cx18 *cx = to_cx18(cxsc->v4l2_dev);
  
  
  	snd_card_free(cxsc->sc);
  	cx->alsa = NULL;
  }
  
  static int __exit cx18_alsa_exit_callback(struct device *dev, void *data)
  {
  	struct v4l2_device *v4l2_dev = dev_get_drvdata(dev);
  	struct snd_cx18_card *cxsc;
  
  	if (v4l2_dev == NULL) {
  		printk(KERN_ERR "cx18-alsa: %s: struct v4l2_device * is NULL\n",
  		       __func__);
  		return 0;
  	}
  
  	cxsc = to_snd_cx18_card(v4l2_dev);
  	if (cxsc == NULL) {
  		CX18_ALSA_WARN("%s: struct snd_cx18_card * is NULL\n",
  			       __func__);
  		return 0;
  	}
  
  	snd_cx18_exit(cxsc);
  	return 0;
  }
  
  static void __exit cx18_alsa_exit(void)
  {
  	struct device_driver *drv;
  	int ret;
  
  	printk(KERN_INFO "cx18-alsa: module unloading...\n");
  
  	drv = driver_find("cx18", &pci_bus_type);
  	ret = driver_for_each_device(drv, NULL, NULL, cx18_alsa_exit_callback);
  	put_driver(drv);
  
  	cx18_ext_init = NULL;
  	printk(KERN_INFO "cx18-alsa: module unload complete\n");
  }
  
  module_init(cx18_alsa_init);
  module_exit(cx18_alsa_exit);
  