/*
 *  hdac-ext-bus.c - HD-audio extended core bus functions.
 *
 *  Copyright (C) 2014-2015 Intel Corp
 *  Author: Jeeja KP <jeeja.kp@intel.com>
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  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; version 2 of the License.
 *
 *  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.
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <sound/hdaudio_ext.h>

MODULE_DESCRIPTION("HDA extended core");
MODULE_LICENSE("GPL v2");

static void hdac_ext_writel(u32 value, u32 __iomem *addr)
{
        writel(value, addr);
}

static u32 hdac_ext_readl(u32 __iomem *addr)
{
        return readl(addr);
}

static void hdac_ext_writew(u16 value, u16 __iomem *addr)
{
        writew(value, addr);
}

static u16 hdac_ext_readw(u16 __iomem *addr)
{
        return readw(addr);
}

static void hdac_ext_writeb(u8 value, u8 __iomem *addr)
{
        writeb(value, addr);
}

static u8 hdac_ext_readb(u8 __iomem *addr)
{
        return readb(addr);
}

static int hdac_ext_dma_alloc_pages(struct hdac_bus *bus, int type,
                           size_t size, struct snd_dma_buffer *buf)
{
        return snd_dma_alloc_pages(type, bus->dev, size, buf);
}

static void hdac_ext_dma_free_pages(struct hdac_bus *bus, struct snd_dma_buffer *buf)
{
        snd_dma_free_pages(buf);
}

static const struct hdac_io_ops hdac_ext_default_io = {
        .reg_writel = hdac_ext_writel,
        .reg_readl = hdac_ext_readl,
        .reg_writew = hdac_ext_writew,
        .reg_readw = hdac_ext_readw,
        .reg_writeb = hdac_ext_writeb,
        .reg_readb = hdac_ext_readb,
        .dma_alloc_pages = hdac_ext_dma_alloc_pages,
        .dma_free_pages = hdac_ext_dma_free_pages,
};

/**
 * snd_hdac_ext_bus_init - initialize a HD-audio extended bus
 * @ebus: the pointer to extended bus object
 * @dev: device pointer
 * @ops: bus verb operators
 * @io_ops: lowlevel I/O operators, can be NULL. If NULL core will use
 * default ops
 *
 * Returns 0 if successful, or a negative error code.
 */
int snd_hdac_ext_bus_init(struct hdac_ext_bus *ebus, struct device *dev,
                        const struct hdac_bus_ops *ops,
                        const struct hdac_io_ops *io_ops)
{
        int ret;
        static int idx;

        /* check if io ops are provided, if not load the defaults */
        if (io_ops == NULL)
                io_ops = &hdac_ext_default_io;

        ret = snd_hdac_bus_init(&ebus->bus, dev, ops, io_ops);
        if (ret < 0)
                return ret;

        INIT_LIST_HEAD(&ebus->hlink_list);
        ebus->idx = idx++;

        mutex_init(&ebus->lock);
        ebus->cmd_dma_state = true;

        return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_init);

/**
 * snd_hdac_ext_bus_exit - clean up a HD-audio extended bus
 * @ebus: the pointer to extended bus object
 */
void snd_hdac_ext_bus_exit(struct hdac_ext_bus *ebus)
{
        snd_hdac_bus_exit(&ebus->bus);
        WARN_ON(!list_empty(&ebus->hlink_list));
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_exit);

static void default_release(struct device *dev)
{
        snd_hdac_ext_bus_device_exit(container_of(dev, struct hdac_device, dev));
}

/**
 * snd_hdac_ext_bus_device_init - initialize the HDA extended codec base device
 * @ebus: hdac extended bus to attach to
 * @addr: codec address
 *
 * Returns zero for success or a negative error code.
 */
int snd_hdac_ext_bus_device_init(struct hdac_ext_bus *ebus, int addr)
{
        struct hdac_ext_device *edev;
        struct hdac_device *hdev = NULL;
        struct hdac_bus *bus = ebus_to_hbus(ebus);
        char name[15];
        int ret;

        edev = kzalloc(sizeof(*edev), GFP_KERNEL);
        if (!edev)
                return -ENOMEM;
        hdev = &edev->hdac;
        edev->ebus = ebus;

        snprintf(name, sizeof(name), "ehdaudio%dD%d", ebus->idx, addr);

        ret  = snd_hdac_device_init(hdev, bus, name, addr);
        if (ret < 0) {
                dev_err(bus->dev, "device init failed for hdac device\n");
                return ret;
        }
        hdev->type = HDA_DEV_ASOC;
        hdev->dev.release = default_release;

        ret = snd_hdac_device_register(hdev);
        if (ret) {
                dev_err(bus->dev, "failed to register hdac device\n");
                snd_hdac_ext_bus_device_exit(hdev);
                return ret;
        }

        return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_device_init);

/**
 * snd_hdac_ext_bus_device_exit - clean up a HD-audio extended codec base device
 * @hdev: hdac device to clean up
 */
void snd_hdac_ext_bus_device_exit(struct hdac_device *hdev)
{
        struct hdac_ext_device *edev = to_ehdac_device(hdev);

        snd_hdac_device_exit(hdev);
        kfree(edev);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_device_exit);

/**
 * snd_hdac_ext_bus_device_remove - remove HD-audio extended codec base devices
 *
 * @ebus: HD-audio extended bus
 */
void snd_hdac_ext_bus_device_remove(struct hdac_ext_bus *ebus)
{
        struct hdac_device *codec, *__codec;
        /*
         * we need to remove all the codec devices objects created in the
         * snd_hdac_ext_bus_device_init
         */
        list_for_each_entry_safe(codec, __codec, &ebus->bus.codec_list, list) {
                snd_hdac_device_unregister(codec);
                put_device(&codec->dev);
        }
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_device_remove);
#define dev_to_hdac(dev) (container_of((dev), \
                        struct hdac_device, dev))

static inline struct hdac_ext_driver *get_edrv(struct device *dev)
{
        struct hdac_driver *hdrv = drv_to_hdac_driver(dev->driver);
        struct hdac_ext_driver *edrv = to_ehdac_driver(hdrv);

        return edrv;
}

static inline struct hdac_ext_device *get_edev(struct device *dev)
{
        struct hdac_device *hdev = dev_to_hdac_dev(dev);
        struct hdac_ext_device *edev = to_ehdac_device(hdev);

        return edev;
}

static int hda_ext_drv_probe(struct device *dev)
{
        return (get_edrv(dev))->probe(get_edev(dev));
}

static int hdac_ext_drv_remove(struct device *dev)
{
        return (get_edrv(dev))->remove(get_edev(dev));
}

static void hdac_ext_drv_shutdown(struct device *dev)
{
        return (get_edrv(dev))->shutdown(get_edev(dev));
}

/**
 * snd_hda_ext_driver_register - register a driver for ext hda devices
 *
 * @drv: ext hda driver structure
 */
int snd_hda_ext_driver_register(struct hdac_ext_driver *drv)
{
        drv->hdac.type = HDA_DEV_ASOC;
        drv->hdac.driver.bus = &snd_hda_bus_type;
        /* we use default match */

        if (drv->probe)
                drv->hdac.driver.probe = hda_ext_drv_probe;
        if (drv->remove)
                drv->hdac.driver.remove = hdac_ext_drv_remove;
        if (drv->shutdown)
                drv->hdac.driver.shutdown = hdac_ext_drv_shutdown;

        return driver_register(&drv->hdac.driver);
}
EXPORT_SYMBOL_GPL(snd_hda_ext_driver_register);

/**
 * snd_hda_ext_driver_unregister - unregister a driver for ext hda devices
 *
 * @drv: ext hda driver structure
 */
void snd_hda_ext_driver_unregister(struct hdac_ext_driver *drv)
{
        driver_unregister(&drv->hdac.driver);
}
EXPORT_SYMBOL_GPL(snd_hda_ext_driver_unregister);