// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  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.
 */

#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-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_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 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;

        /* FIXME - take any other stopping actions needed */

        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_obj(struct snd_cx18_card);
        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 */
        strscpy(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_new(&cx->pci_dev->dev,
                           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_new() 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;
        }
        /* FIXME - proc files */

        /* (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);
        kfree(cxsc);
err_exit:
        return ret;
}

static 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.v4l2_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);

        /* FIXME - pointer checks & shutdown cxsc */

        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);
        (void)ret;      /* suppress compiler warning */

        cx18_ext_init = NULL;
        printk(KERN_INFO "cx18-alsa: module unload complete\n");
}

module_init(cx18_alsa_init);
module_exit(cx18_alsa_exit);