// SPDX-License-Identifier: GPL-2.0-only
/*
 *  hdac-ext-stream.c - HD-audio extended stream operations.
 *
 *  Copyright (C) 2015 Intel Corp
 *  Author: Jeeja KP <jeeja.kp@intel.com>
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */

#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/pci_ids.h>
#include <linux/slab.h>
#include <sound/pcm.h>
#include <sound/hda_register.h>
#include <sound/hdaudio_ext.h>
#include <sound/compress_driver.h>

/**
 * snd_hdac_ext_host_stream_setup - Setup a HOST stream.
 * @hext_stream: HDAudio stream to set up.
 * @code_loading: Whether the stream is for PCM or code-loading.
 *
 * Return: Zero on success or negative error code.
 */
int snd_hdac_ext_host_stream_setup(struct hdac_ext_stream *hext_stream, bool code_loading)
{
        return hext_stream->host_setup(hdac_stream(hext_stream), code_loading);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_host_stream_setup);

/**
 * snd_hdac_apl_host_stream_setup - Setup a HOST stream following procedure
 *                                  recommended for ApolloLake devices.
 * @hstream: HDAudio stream to set up.
 * @code_loading: Whether the stream is for PCM or code-loading.
 *
 * Return: Zero on success or negative error code.
 */
static int snd_hdac_apl_host_stream_setup(struct hdac_stream *hstream, bool code_loading)
{
        struct hdac_ext_stream *hext_stream = stream_to_hdac_ext_stream(hstream);
        int ret;

        snd_hdac_ext_stream_decouple(hstream->bus, hext_stream, false);
        ret = snd_hdac_stream_setup(hstream, code_loading);
        snd_hdac_ext_stream_decouple(hstream->bus, hext_stream, true);

        return ret;
}

/**
 * snd_hdac_ext_stream_init - initialize each stream (aka device)
 * @bus: HD-audio core bus
 * @hext_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
 */
static void snd_hdac_ext_stream_init(struct hdac_bus *bus,
                                     struct hdac_ext_stream *hext_stream,
                                     int idx, int direction, int tag)
{
        if (bus->ppcap) {
                hext_stream->pphc_addr = bus->ppcap + AZX_PPHC_BASE +
                                AZX_PPHC_INTERVAL * idx;

                hext_stream->pplc_addr = bus->ppcap + AZX_PPLC_BASE +
                                AZX_PPLC_MULTI * bus->num_streams +
                                AZX_PPLC_INTERVAL * idx;
        }

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

/**
 * snd_hdac_ext_stream_init_all - create and initialize the stream objects
 *   for an extended hda bus
 * @bus: HD-audio 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_bus *bus, int start_idx,
                                 int num_stream, int dir)
{
        struct pci_dev *pci = to_pci_dev(bus->dev);
        int (*setup_op)(struct hdac_stream *, bool);
        int stream_tag = 0;
        int i, tag, idx = start_idx;

        if (pci->device == PCI_DEVICE_ID_INTEL_HDA_APL)
                setup_op = snd_hdac_apl_host_stream_setup;
        else
                setup_op = snd_hdac_stream_setup;

        for (i = 0; i < num_stream; i++) {
                struct hdac_ext_stream *hext_stream = kzalloc_obj(*hext_stream);
                if (!hext_stream)
                        return -ENOMEM;
                tag = ++stream_tag;
                snd_hdac_ext_stream_init(bus, hext_stream, idx, dir, tag);
                idx++;
                hext_stream->host_setup = setup_op;
        }

        return 0;

}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_init_all);

/**
 * snd_hdac_ext_stream_free_all - free hdac extended stream objects
 *
 * @bus: HD-audio core bus
 */
void snd_hdac_ext_stream_free_all(struct hdac_bus *bus)
{
        struct hdac_stream *s, *_s;
        struct hdac_ext_stream *hext_stream;

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

void snd_hdac_ext_stream_decouple_locked(struct hdac_bus *bus,
                                         struct hdac_ext_stream *hext_stream,
                                         bool decouple)
{
        struct hdac_stream *hstream = &hext_stream->hstream;
        u32 val;
        int mask = AZX_PPCTL_PROCEN(hstream->index);

        val = readw(bus->ppcap + AZX_REG_PP_PPCTL) & mask;

        if (decouple && !val)
                snd_hdac_updatel(bus->ppcap, AZX_REG_PP_PPCTL, mask, mask);
        else if (!decouple && val)
                snd_hdac_updatel(bus->ppcap, AZX_REG_PP_PPCTL, mask, 0);

        hext_stream->decoupled = decouple;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_decouple_locked);

/**
 * snd_hdac_ext_stream_decouple - decouple the hdac stream
 * @bus: HD-audio core bus
 * @hext_stream: HD-audio ext core stream object to initialize
 * @decouple: flag to decouple
 */
void snd_hdac_ext_stream_decouple(struct hdac_bus *bus,
                                  struct hdac_ext_stream *hext_stream, bool decouple)
{
        guard(spinlock_irq)(&bus->reg_lock);
        snd_hdac_ext_stream_decouple_locked(bus, hext_stream, decouple);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_decouple);

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

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

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

        snd_hdac_ext_stream_clear(hext_stream);

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

}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_reset);

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

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

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

        return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_setup);

static struct hdac_ext_stream *
hdac_ext_link_dma_stream_assign(struct hdac_bus *bus,
                                struct snd_pcm_substream *substream)
{
        struct hdac_ext_stream *res = NULL;
        struct hdac_stream *hstream = NULL;

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

        guard(spinlock_irq)(&bus->reg_lock);
        list_for_each_entry(hstream, &bus->stream_list, list) {
                struct hdac_ext_stream *hext_stream = container_of(hstream,
                                                                 struct hdac_ext_stream,
                                                                 hstream);
                if (hstream->direction != substream->stream)
                        continue;

                /* check if link stream is available */
                if (!hext_stream->link_locked) {
                        res = hext_stream;
                        break;
                }

        }
        if (res) {
                snd_hdac_ext_stream_decouple_locked(bus, res, true);
                res->link_locked = 1;
                res->link_substream = substream;
        }
        return res;
}

static struct hdac_ext_stream *
hdac_ext_host_dma_stream_assign(struct hdac_bus *bus,
                                struct snd_pcm_substream *substream)
{
        struct hdac_ext_stream *res = NULL;
        struct hdac_stream *hstream = NULL;

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

        guard(spinlock_irq)(&bus->reg_lock);
        list_for_each_entry(hstream, &bus->stream_list, list) {
                struct hdac_ext_stream *hext_stream = container_of(hstream,
                                                                 struct hdac_ext_stream,
                                                                 hstream);
                if (hstream->direction != substream->stream)
                        continue;

                if (!hstream->opened) {
                        res = hext_stream;
                        break;
                }
        }
        if (res) {
                snd_hdac_ext_stream_decouple_locked(bus, res, true);
                res->hstream.opened = 1;
                res->hstream.running = 0;
                res->hstream.substream = substream;
        }

        return res;
}

/**
 * snd_hdac_ext_stream_assign - assign a stream for the PCM
 * @bus: HD-audio 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_bus *bus,
                                           struct snd_pcm_substream *substream,
                                           int type)
{
        struct hdac_ext_stream *hext_stream = NULL;
        struct hdac_stream *hstream = NULL;

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

        case HDAC_EXT_STREAM_TYPE_HOST:
                return hdac_ext_host_dma_stream_assign(bus, substream);

        case HDAC_EXT_STREAM_TYPE_LINK:
                return hdac_ext_link_dma_stream_assign(bus, substream);

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

/**
 * snd_hdac_ext_stream_release - release the assigned stream
 * @hext_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 *hext_stream, int type)
{
        struct hdac_bus *bus = hext_stream->hstream.bus;

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

        case HDAC_EXT_STREAM_TYPE_HOST:
                scoped_guard(spinlock_irq, &bus->reg_lock) {
                        /* couple link only if not in use */
                        if (!hext_stream->link_locked)
                                snd_hdac_ext_stream_decouple_locked(bus, hext_stream, false);
                        snd_hdac_stream_release_locked(&hext_stream->hstream);
                }
                break;

        case HDAC_EXT_STREAM_TYPE_LINK:
                scoped_guard(spinlock_irq, &bus->reg_lock) {
                        /* couple host only if not in use */
                        if (!hext_stream->hstream.opened)
                                snd_hdac_ext_stream_decouple_locked(bus, hext_stream, false);
                        hext_stream->link_locked = 0;
                        hext_stream->link_substream = NULL;
                }
                break;

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

}
EXPORT_SYMBOL_GPL(snd_hdac_ext_stream_release);

/**
 * snd_hdac_ext_cstream_assign - assign a host stream for compress
 * @bus: HD-audio core bus
 * @cstream: Compress stream to assign
 *
 * Assign an unused host stream for the given compress stream.
 * If no stream is free, NULL is returned. Stream is decoupled
 * before assignment.
 */
struct hdac_ext_stream *snd_hdac_ext_cstream_assign(struct hdac_bus *bus,
                                                    struct snd_compr_stream *cstream)
{
        struct hdac_ext_stream *res = NULL;
        struct hdac_stream *hstream;

        guard(spinlock_irq)(&bus->reg_lock);
        list_for_each_entry(hstream, &bus->stream_list, list) {
                struct hdac_ext_stream *hext_stream = stream_to_hdac_ext_stream(hstream);

                if (hstream->direction != cstream->direction)
                        continue;

                if (!hstream->opened) {
                        res = hext_stream;
                        break;
                }
        }

        if (res) {
                snd_hdac_ext_stream_decouple_locked(bus, res, true);
                res->hstream.opened = 1;
                res->hstream.running = 0;
                res->hstream.cstream = cstream;
        }

        return res;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_cstream_assign);