/*
 *  hdac-ext-stream.c - HD-audio extended stream operations.
 *
 *  Copyright (C) 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/delay.h>
#include <linux/slab.h>
#include <sound/pcm.h>
#include <sound/hda_register.h>
#include <sound/hdaudio_ext.h>

/**
 * snd_hdac_ext_stream_init - initialize each stream (aka device)
 * @ebus: HD-audio ext core bus
 * @stream: HD-audio ext core stream object to initialize
 * @idx: stream index number
 * @direction: stream direction (SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE)
 * @tag: the tag id to assign
 *
 * initialize the stream, if ppcap is enabled then init those and then
 * invoke hdac stream initialization routine
 */
void snd_hdac_ext_stream_init(struct hdac_ext_bus *ebus,
                                struct hdac_ext_stream *stream,
                                int idx, int direction, int tag)
{
        struct hdac_bus *bus = &ebus->bus;

        if (ebus->ppcap) {
                stream->pphc_addr = ebus->ppcap + AZX_PPHC_BASE +
                                AZX_PPHC_INTERVAL * idx;

                stream->pplc_addr = ebus->ppcap + AZX_PPLC_BASE +
                                AZX_PPLC_MULTI * ebus->num_streams +
                                AZX_PPLC_INTERVAL * idx;
        }

        if (ebus->spbcap) {
                stream->spib_addr = ebus->spbcap + AZX_SPB_BASE +
                                        AZX_SPB_INTERVAL * idx +
                                        AZX_SPB_SPIB;

                stream->fifo_addr = ebus->spbcap + AZX_SPB_BASE +
                                        AZX_SPB_INTERVAL * idx +
                                        AZX_SPB_MAXFIFO;
        }

        if (ebus->drsmcap)
                stream->dpibr_addr = ebus->drsmcap + AZX_DRSM_BASE +
                                        AZX_DRSM_INTERVAL * idx;

        stream->decoupled = false;
        snd_hdac_stream_init(bus, &stream->hstream, idx, direction, tag);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_init);

/**
 * snd_hdac_ext_stream_init_all - create and initialize the stream objects
 *   for an extended hda bus
 * @ebus: HD-audio ext core bus
 * @start_idx: start index for streams
 * @num_stream: number of streams to initialize
 * @dir: direction of streams
 */
int snd_hdac_ext_stream_init_all(struct hdac_ext_bus *ebus, int start_idx,
                int num_stream, int dir)
{
        int stream_tag = 0;
        int i, tag, idx = start_idx;

        for (i = 0; i < num_stream; i++) {
                struct hdac_ext_stream *stream =
                                kzalloc(sizeof(*stream), GFP_KERNEL);
                if (!stream)
                        return -ENOMEM;
                tag = ++stream_tag;
                snd_hdac_ext_stream_init(ebus, stream, idx, dir, tag);
                idx++;
        }

        return 0;

}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_init_all);

/**
 * snd_hdac_stream_free_all - free hdac extended stream objects
 *
 * @ebus: HD-audio ext core bus
 */
void snd_hdac_stream_free_all(struct hdac_ext_bus *ebus)
{
        struct hdac_stream *s, *_s;
        struct hdac_ext_stream *stream;
        struct hdac_bus *bus = ebus_to_hbus(ebus);

        list_for_each_entry_safe(s, _s, &bus->stream_list, list) {
                stream = stream_to_hdac_ext_stream(s);
                snd_hdac_ext_stream_decouple(ebus, stream, false);
                list_del(&s->list);
                kfree(stream);
        }
}
EXPORT_SYMBOL_GPL(snd_hdac_stream_free_all);

/**
 * snd_hdac_ext_stream_decouple - decouple the hdac stream
 * @ebus: HD-audio ext core bus
 * @stream: HD-audio ext core stream object to initialize
 * @decouple: flag to decouple
 */
void snd_hdac_ext_stream_decouple(struct hdac_ext_bus *ebus,
                                struct hdac_ext_stream *stream, bool decouple)
{
        struct hdac_stream *hstream = &stream->hstream;
        struct hdac_bus *bus = &ebus->bus;

        spin_lock_irq(&bus->reg_lock);
        if (decouple)
                snd_hdac_updatel(ebus->ppcap, AZX_REG_PP_PPCTL, 0,
                                AZX_PPCTL_PROCEN(hstream->index));
        else
                snd_hdac_updatel(ebus->ppcap, AZX_REG_PP_PPCTL,
                                        AZX_PPCTL_PROCEN(hstream->index), 0);
        stream->decoupled = decouple;
        spin_unlock_irq(&bus->reg_lock);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_decouple);

/**
 * snd_hdac_ext_linkstream_start - start a stream
 * @stream: HD-audio ext core stream to start
 */
void snd_hdac_ext_link_stream_start(struct hdac_ext_stream *stream)
{
        snd_hdac_updatel(stream->pplc_addr, AZX_REG_PPLCCTL, 0, AZX_PPLCCTL_RUN);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_link_stream_start);

/**
 * snd_hdac_ext_link_stream_clear - stop a stream DMA
 * @stream: HD-audio ext core stream to stop
 */
void snd_hdac_ext_link_stream_clear(struct hdac_ext_stream *stream)
{
        snd_hdac_updatel(stream->pplc_addr, AZX_REG_PPLCCTL, AZX_PPLCCTL_RUN, 0);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_link_stream_clear);

/**
 * snd_hdac_ext_link_stream_reset - reset a stream
 * @stream: HD-audio ext core stream to reset
 */
void snd_hdac_ext_link_stream_reset(struct hdac_ext_stream *stream)
{
        unsigned char val;
        int timeout;

        snd_hdac_ext_link_stream_clear(stream);

        snd_hdac_updatel(stream->pplc_addr, AZX_REG_PPLCCTL, 0, AZX_PPLCCTL_STRST);
        udelay(3);
        timeout = 50;
        do {
                val = readl(stream->pplc_addr + AZX_REG_PPLCCTL) &
                                AZX_PPLCCTL_STRST;
                if (val)
                        break;
                udelay(3);
        } while (--timeout);
        val &= ~AZX_PPLCCTL_STRST;
        writel(val, stream->pplc_addr + AZX_REG_PPLCCTL);
        udelay(3);

        timeout = 50;
        /* waiting for hardware to report that the stream is out of reset */
        do {
                val = readl(stream->pplc_addr + AZX_REG_PPLCCTL) & AZX_PPLCCTL_STRST;
                if (!val)
                        break;
                udelay(3);
        } while (--timeout);

}
EXPORT_SYMBOL_GPL(snd_hdac_ext_link_stream_reset);

/**
 * snd_hdac_ext_link_stream_setup -  set up the SD for streaming
 * @stream: HD-audio ext core stream to set up
 * @fmt: stream format
 */
int snd_hdac_ext_link_stream_setup(struct hdac_ext_stream *stream, int fmt)
{
        struct hdac_stream *hstream = &stream->hstream;
        unsigned int val;

        /* make sure the run bit is zero for SD */
        snd_hdac_ext_link_stream_clear(stream);
        /* program the stream_tag */
        val = readl(stream->pplc_addr + AZX_REG_PPLCCTL);
        val = (val & ~AZX_PPLCCTL_STRM_MASK) |
                (hstream->stream_tag << AZX_PPLCCTL_STRM_SHIFT);
        writel(val, stream->pplc_addr + AZX_REG_PPLCCTL);

        /* program the stream format */
        writew(fmt, stream->pplc_addr + AZX_REG_PPLCFMT);

        return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_link_stream_setup);

/**
 * snd_hdac_ext_link_set_stream_id - maps stream id to link output
 * @link: HD-audio ext link to set up
 * @stream: stream id
 */
void snd_hdac_ext_link_set_stream_id(struct hdac_ext_link *link,
                                 int stream)
{
        snd_hdac_updatew(link->ml_addr, AZX_REG_ML_LOSIDV, (1 << stream), 1 << stream);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_link_set_stream_id);

/**
 * snd_hdac_ext_link_clear_stream_id - maps stream id to link output
 * @link: HD-audio ext link to set up
 * @stream: stream id
 */
void snd_hdac_ext_link_clear_stream_id(struct hdac_ext_link *link,
                                 int stream)
{
        snd_hdac_updatew(link->ml_addr, AZX_REG_ML_LOSIDV, 0, (1 << stream));
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_link_clear_stream_id);

static struct hdac_ext_stream *
hdac_ext_link_stream_assign(struct hdac_ext_bus *ebus,
                                struct snd_pcm_substream *substream)
{
        struct hdac_ext_stream *res = NULL;
        struct hdac_stream *stream = NULL;
        struct hdac_bus *hbus = &ebus->bus;

        if (!ebus->ppcap) {
                dev_err(hbus->dev, "stream type not supported\n");
                return NULL;
        }

        list_for_each_entry(stream, &hbus->stream_list, list) {
                struct hdac_ext_stream *hstream = container_of(stream,
                                                struct hdac_ext_stream,
                                                hstream);
                if (stream->direction != substream->stream)
                        continue;

                /* check if decoupled stream and not in use is available */
                if (hstream->decoupled && !hstream->link_locked) {
                        res = hstream;
                        break;
                }

                if (!hstream->link_locked) {
                        snd_hdac_ext_stream_decouple(ebus, hstream, true);
                        res = hstream;
                        break;
                }
        }
        if (res) {
                spin_lock_irq(&hbus->reg_lock);
                res->link_locked = 1;
                res->link_substream = substream;
                spin_unlock_irq(&hbus->reg_lock);
        }
        return res;
}

static struct hdac_ext_stream *
hdac_ext_host_stream_assign(struct hdac_ext_bus *ebus,
                                struct snd_pcm_substream *substream)
{
        struct hdac_ext_stream *res = NULL;
        struct hdac_stream *stream = NULL;
        struct hdac_bus *hbus = &ebus->bus;

        if (!ebus->ppcap) {
                dev_err(hbus->dev, "stream type not supported\n");
                return NULL;
        }

        list_for_each_entry(stream, &hbus->stream_list, list) {
                struct hdac_ext_stream *hstream = container_of(stream,
                                                struct hdac_ext_stream,
                                                hstream);
                if (stream->direction != substream->stream)
                        continue;

                if (!stream->opened) {
                        if (!hstream->decoupled)
                                snd_hdac_ext_stream_decouple(ebus, hstream, true);
                        res = hstream;
                        break;
                }
        }
        if (res) {
                spin_lock_irq(&hbus->reg_lock);
                res->hstream.opened = 1;
                res->hstream.running = 0;
                res->hstream.substream = substream;
                spin_unlock_irq(&hbus->reg_lock);
        }

        return res;
}

/**
 * snd_hdac_ext_stream_assign - assign a stream for the PCM
 * @ebus: HD-audio ext core bus
 * @substream: PCM substream to assign
 * @type: type of stream (coupled, host or link stream)
 *
 * This assigns the stream based on the type (coupled/host/link), for the
 * given PCM substream, assigns it and returns the stream object
 *
 * coupled: Looks for an unused stream
 * host: Looks for an unused decoupled host stream
 * link: Looks for an unused decoupled link stream
 *
 * If no stream is free, returns NULL. The function tries to keep using
 * the same stream object when it's used beforehand.  when a stream is
 * decoupled, it becomes a host stream and link stream.
 */
struct hdac_ext_stream *snd_hdac_ext_stream_assign(struct hdac_ext_bus *ebus,
                                           struct snd_pcm_substream *substream,
                                           int type)
{
        struct hdac_ext_stream *hstream = NULL;
        struct hdac_stream *stream = NULL;
        struct hdac_bus *hbus = &ebus->bus;

        switch (type) {
        case HDAC_EXT_STREAM_TYPE_COUPLED:
                stream = snd_hdac_stream_assign(hbus, substream);
                if (stream)
                        hstream = container_of(stream,
                                        struct hdac_ext_stream, hstream);
                return hstream;

        case HDAC_EXT_STREAM_TYPE_HOST:
                return hdac_ext_host_stream_assign(ebus, substream);

        case HDAC_EXT_STREAM_TYPE_LINK:
                return hdac_ext_link_stream_assign(ebus, substream);

        default:
                return NULL;
        }
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_assign);

/**
 * snd_hdac_ext_stream_release - release the assigned stream
 * @stream: HD-audio ext core stream to release
 * @type: type of stream (coupled, host or link stream)
 *
 * Release the stream that has been assigned by snd_hdac_ext_stream_assign().
 */
void snd_hdac_ext_stream_release(struct hdac_ext_stream *stream, int type)
{
        struct hdac_bus *bus = stream->hstream.bus;
        struct hdac_ext_bus *ebus = hbus_to_ebus(bus);

        switch (type) {
        case HDAC_EXT_STREAM_TYPE_COUPLED:
                snd_hdac_stream_release(&stream->hstream);
                break;

        case HDAC_EXT_STREAM_TYPE_HOST:
                if (stream->decoupled && !stream->link_locked)
                        snd_hdac_ext_stream_decouple(ebus, stream, false);
                snd_hdac_stream_release(&stream->hstream);
                break;

        case HDAC_EXT_STREAM_TYPE_LINK:
                if (stream->decoupled && !stream->hstream.opened)
                        snd_hdac_ext_stream_decouple(ebus, stream, false);
                spin_lock_irq(&bus->reg_lock);
                stream->link_locked = 0;
                stream->link_substream = NULL;
                spin_unlock_irq(&bus->reg_lock);
                break;

        default:
                dev_dbg(bus->dev, "Invalid type %d\n", type);
        }

}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_release);

/**
 * snd_hdac_ext_stream_spbcap_enable - enable SPIB for a stream
 * @ebus: HD-audio ext core bus
 * @enable: flag to enable/disable SPIB
 * @index: stream index for which SPIB need to be enabled
 */
void snd_hdac_ext_stream_spbcap_enable(struct hdac_ext_bus *ebus,
                                 bool enable, int index)
{
        u32 mask = 0;
        u32 register_mask = 0;
        struct hdac_bus *bus = &ebus->bus;

        if (!ebus->spbcap) {
                dev_err(bus->dev, "Address of SPB capability is NULL");
                return;
        }

        mask |= (1 << index);

        register_mask = readl(ebus->spbcap + AZX_REG_SPB_SPBFCCTL);

        mask |= register_mask;

        if (enable)
                snd_hdac_updatel(ebus->spbcap, AZX_REG_SPB_SPBFCCTL, 0, mask);
        else
                snd_hdac_updatel(ebus->spbcap, AZX_REG_SPB_SPBFCCTL, mask, 0);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_spbcap_enable);

/**
 * snd_hdac_ext_stream_set_spib - sets the spib value of a stream
 * @ebus: HD-audio ext core bus
 * @stream: hdac_ext_stream
 * @value: spib value to set
 */
int snd_hdac_ext_stream_set_spib(struct hdac_ext_bus *ebus,
                                 struct hdac_ext_stream *stream, u32 value)
{
        struct hdac_bus *bus = &ebus->bus;

        if (!ebus->spbcap) {
                dev_err(bus->dev, "Address of SPB capability is NULL");
                return -EINVAL;
        }

        writel(value, stream->spib_addr);

        return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_set_spib);

/**
 * snd_hdac_ext_stream_get_spbmaxfifo - gets the spib value of a stream
 * @ebus: HD-audio ext core bus
 * @stream: hdac_ext_stream
 *
 * Return maxfifo for the stream
 */
int snd_hdac_ext_stream_get_spbmaxfifo(struct hdac_ext_bus *ebus,
                                 struct hdac_ext_stream *stream)
{
        struct hdac_bus *bus = &ebus->bus;

        if (!ebus->spbcap) {
                dev_err(bus->dev, "Address of SPB capability is NULL");
                return -EINVAL;
        }

        return readl(stream->fifo_addr);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_get_spbmaxfifo);


/**
 * snd_hdac_ext_stop_streams - stop all stream if running
 * @ebus: HD-audio ext core bus
 */
void snd_hdac_ext_stop_streams(struct hdac_ext_bus *ebus)
{
        struct hdac_bus *bus = ebus_to_hbus(ebus);
        struct hdac_stream *stream;

        if (bus->chip_init) {
                list_for_each_entry(stream, &bus->stream_list, list)
                        snd_hdac_stream_stop(stream);
                snd_hdac_bus_stop_chip(bus);
        }
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stop_streams);

/**
 * snd_hdac_ext_stream_drsm_enable - enable DMA resume for a stream
 * @ebus: HD-audio ext core bus
 * @enable: flag to enable/disable DRSM
 * @index: stream index for which DRSM need to be enabled
 */
void snd_hdac_ext_stream_drsm_enable(struct hdac_ext_bus *ebus,
                                bool enable, int index)
{
        u32 mask = 0;
        u32 register_mask = 0;
        struct hdac_bus *bus = &ebus->bus;

        if (!ebus->drsmcap) {
                dev_err(bus->dev, "Address of DRSM capability is NULL");
                return;
        }

        mask |= (1 << index);

        register_mask = readl(ebus->drsmcap + AZX_REG_SPB_SPBFCCTL);

        mask |= register_mask;

        if (enable)
                snd_hdac_updatel(ebus->drsmcap, AZX_REG_DRSM_CTL, 0, mask);
        else
                snd_hdac_updatel(ebus->drsmcap, AZX_REG_DRSM_CTL, mask, 0);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_drsm_enable);

/**
 * snd_hdac_ext_stream_set_dpibr - sets the dpibr value of a stream
 * @ebus: HD-audio ext core bus
 * @stream: hdac_ext_stream
 * @value: dpib value to set
 */
int snd_hdac_ext_stream_set_dpibr(struct hdac_ext_bus *ebus,
                                 struct hdac_ext_stream *stream, u32 value)
{
        struct hdac_bus *bus = &ebus->bus;

        if (!ebus->drsmcap) {
                dev_err(bus->dev, "Address of DRSM capability is NULL");
                return -EINVAL;
        }

        writel(value, stream->dpibr_addr);

        return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_set_dpibr);

/**
 * snd_hdac_ext_stream_set_lpib - sets the lpib value of a stream
 * @ebus: HD-audio ext core bus
 * @stream: hdac_ext_stream
 * @value: lpib value to set
 */
int snd_hdac_ext_stream_set_lpib(struct hdac_ext_stream *stream, u32 value)
{
        snd_hdac_stream_writel(&stream->hstream, SD_LPIB, value);

        return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_set_lpib);