/*
 * Renesas R-Car SRC support
 *
 * Copyright (C) 2013 Renesas Solutions Corp.
 * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include "rsnd.h"

#define SRC_NAME "src"

/* SRCx_STATUS */
#define OUF_SRCO        ((1 << 12) | (1 << 13))
#define OUF_SRCI        ((1 <<  9) | (1 <<  8))

/* SCU_SYSTEM_STATUS0/1 */
#define OUF_SRC(id)     ((1 << (id + 16)) | (1 << id))

struct rsnd_src {
        struct rsnd_mod mod;
        struct rsnd_mod *dma;
        struct rsnd_kctrl_cfg_s sen;  /* sync convert enable */
        struct rsnd_kctrl_cfg_s sync; /* sync convert */
        u32 convert_rate; /* sampling rate convert */
        int err;
        int irq;
};

#define RSND_SRC_NAME_SIZE 16

#define rsnd_src_get(priv, id) ((struct rsnd_src *)(priv->src) + id)
#define rsnd_src_to_dma(src) ((src)->dma)
#define rsnd_src_nr(priv) ((priv)->src_nr)
#define rsnd_enable_sync_convert(src) ((src)->sen.val)

#define rsnd_mod_to_src(_mod)                           \
        container_of((_mod), struct rsnd_src, mod)

#define for_each_rsnd_src(pos, priv, i)                         \
        for ((i) = 0;                                           \
             ((i) < rsnd_src_nr(priv)) &&                       \
             ((pos) = (struct rsnd_src *)(priv)->src + i);      \
             i++)


/*
 *              image of SRC (Sampling Rate Converter)
 *
 * 96kHz   <-> +-----+  48kHz   +-----+  48kHz  +-------+
 * 48kHz   <-> | SRC | <------> | SSI | <-----> | codec |
 * 44.1kHz <-> +-----+          +-----+         +-------+
 * ...
 *
 */

/*
 * src.c is caring...
 *
 * Gen1
 *
 * [mem] -> [SRU] -> [SSI]
 *        |--------|
 *
 * Gen2
 *
 * [mem] -> [SRC] -> [SSIU] -> [SSI]
 *        |-----------------|
 */

static void rsnd_src_activation(struct rsnd_mod *mod)
{
        rsnd_mod_write(mod, SRC_SWRSR, 0);
        rsnd_mod_write(mod, SRC_SWRSR, 1);
}

static void rsnd_src_halt(struct rsnd_mod *mod)
{
        rsnd_mod_write(mod, SRC_SRCIR, 1);
        rsnd_mod_write(mod, SRC_SWRSR, 0);
}

static struct dma_chan *rsnd_src_dma_req(struct rsnd_dai_stream *io,
                                         struct rsnd_mod *mod)
{
        struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
        int is_play = rsnd_io_is_play(io);

        return rsnd_dma_request_channel(rsnd_src_of_node(priv),
                                        mod,
                                        is_play ? "rx" : "tx");
}

static u32 rsnd_src_convert_rate(struct rsnd_dai_stream *io,
                                 struct rsnd_src *src)
{
        struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
        u32 convert_rate;

        if (!runtime)
                return 0;

        if (!rsnd_enable_sync_convert(src))
                return src->convert_rate;

        convert_rate = src->sync.val;

        if (!convert_rate)
                convert_rate = src->convert_rate;

        if (!convert_rate)
                convert_rate = runtime->rate;

        return convert_rate;
}

unsigned int rsnd_src_get_ssi_rate(struct rsnd_priv *priv,
                                   struct rsnd_dai_stream *io,
                                   struct snd_pcm_runtime *runtime)
{
        struct rsnd_mod *src_mod = rsnd_io_to_mod_src(io);
        struct rsnd_src *src;
        unsigned int rate = 0;

        if (src_mod) {
                src = rsnd_mod_to_src(src_mod);

                /*
                 * return convert rate if SRC is used,
                 * otherwise, return runtime->rate as usual
                 */
                rate = rsnd_src_convert_rate(io, src);
        }

        if (!rate)
                rate = runtime->rate;

        return rate;
}

static int rsnd_src_hw_params(struct rsnd_mod *mod,
                              struct rsnd_dai_stream *io,
                              struct snd_pcm_substream *substream,
                              struct snd_pcm_hw_params *fe_params)
{
        struct rsnd_src *src = rsnd_mod_to_src(mod);
        struct snd_soc_pcm_runtime *fe = substream->private_data;

        /*
         * SRC assumes that it is used under DPCM if user want to use
         * sampling rate convert. Then, SRC should be FE.
         * And then, this function will be called *after* BE settings.
         * this means, each BE already has fixuped hw_params.
         * see
         *      dpcm_fe_dai_hw_params()
         *      dpcm_be_dai_hw_params()
         */
        if (fe->dai_link->dynamic) {
                int stream = substream->stream;
                struct snd_soc_dpcm *dpcm;
                struct snd_pcm_hw_params *be_params;

                list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
                        be_params = &dpcm->hw_params;

                        if (params_rate(fe_params) != params_rate(be_params))
                                src->convert_rate = params_rate(be_params);
                }
        }

        return 0;
}

static void rsnd_src_set_convert_rate(struct rsnd_dai_stream *io,
                                      struct rsnd_mod *mod)
{
        struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
        struct device *dev = rsnd_priv_to_dev(priv);
        struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
        struct rsnd_src *src = rsnd_mod_to_src(mod);
        u32 convert_rate = rsnd_src_convert_rate(io, src);
        u32 ifscr, fsrate, adinr;
        u32 cr, route;
        u32 bsdsr, bsisr;
        uint ratio;

        if (!runtime)
                return;

        /* 6 - 1/6 are very enough ratio for SRC_BSDSR */
        if (!convert_rate)
                ratio = 0;
        else if (convert_rate > runtime->rate)
                ratio = 100 * convert_rate / runtime->rate;
        else
                ratio = 100 * runtime->rate / convert_rate;

        if (ratio > 600) {
                dev_err(dev, "FSO/FSI ratio error\n");
                return;
        }

        /*
         *      SRC_ADINR
         */
        adinr = rsnd_get_adinr_bit(mod, io) |
                rsnd_get_adinr_chan(mod, io);

        /*
         *      SRC_IFSCR / SRC_IFSVR
         */
        ifscr = 0;
        fsrate = 0;
        if (convert_rate) {
                ifscr = 1;
                fsrate = 0x0400000 / convert_rate * runtime->rate;
        }

        /*
         *      SRC_SRCCR / SRC_ROUTE_MODE0
         */
        cr      = 0x00011110;
        route   = 0x0;
        if (convert_rate) {
                route   = 0x1;

                if (rsnd_enable_sync_convert(src)) {
                        cr |= 0x1;
                        route |= rsnd_io_is_play(io) ?
                                (0x1 << 24) : (0x1 << 25);
                }
        }

        /*
         * SRC_BSDSR / SRC_BSISR
         */
        switch (rsnd_mod_id(mod)) {
        case 5:
        case 6:
        case 7:
        case 8:
                bsdsr = 0x02400000; /* 6 - 1/6 */
                bsisr = 0x00100060; /* 6 - 1/6 */
                break;
        default:
                bsdsr = 0x01800000; /* 6 - 1/6 */
                bsisr = 0x00100060 ;/* 6 - 1/6 */
                break;
        }

        rsnd_mod_write(mod, SRC_SRCIR, 1);      /* initialize */
        rsnd_mod_write(mod, SRC_ADINR, adinr);
        rsnd_mod_write(mod, SRC_IFSCR, ifscr);
        rsnd_mod_write(mod, SRC_IFSVR, fsrate);
        rsnd_mod_write(mod, SRC_SRCCR, cr);
        rsnd_mod_write(mod, SRC_BSDSR, bsdsr);
        rsnd_mod_write(mod, SRC_BSISR, bsisr);
        rsnd_mod_write(mod, SRC_SRCIR, 0);      /* cancel initialize */

        rsnd_mod_write(mod, SRC_ROUTE_MODE0, route);
        rsnd_mod_write(mod, SRC_I_BUSIF_MODE, 1);
        rsnd_mod_write(mod, SRC_O_BUSIF_MODE, 1);
        rsnd_mod_write(mod, SRC_BUSIF_DALIGN, rsnd_get_dalign(mod, io));

        if (convert_rate)
                rsnd_adg_set_convert_clk_gen2(mod, io,
                                              runtime->rate,
                                              convert_rate);
        else
                rsnd_adg_set_convert_timing_gen2(mod, io);
}

#define rsnd_src_irq_enable(mod)  rsnd_src_irq_ctrol(mod, 1)
#define rsnd_src_irq_disable(mod) rsnd_src_irq_ctrol(mod, 0)
static void rsnd_src_irq_ctrol(struct rsnd_mod *mod, int enable)
{
        struct rsnd_src *src = rsnd_mod_to_src(mod);
        u32 sys_int_val, int_val, sys_int_mask;
        int irq = src->irq;
        int id = rsnd_mod_id(mod);

        sys_int_val =
        sys_int_mask = OUF_SRC(id);
        int_val = 0x3300;

        /*
         * IRQ is not supported on non-DT
         * see
         *      rsnd_src_probe_()
         */
        if ((irq <= 0) || !enable) {
                sys_int_val = 0;
                int_val = 0;
        }

        /*
         * WORKAROUND
         *
         * ignore over flow error when rsnd_enable_sync_convert()
         */
        if (rsnd_enable_sync_convert(src))
                sys_int_val = sys_int_val & 0xffff;

        rsnd_mod_write(mod, SRC_INT_ENABLE0, int_val);
        rsnd_mod_bset(mod, SCU_SYS_INT_EN0, sys_int_mask, sys_int_val);
        rsnd_mod_bset(mod, SCU_SYS_INT_EN1, sys_int_mask, sys_int_val);
}

static void rsnd_src_status_clear(struct rsnd_mod *mod)
{
        u32 val = OUF_SRC(rsnd_mod_id(mod));

        rsnd_mod_bset(mod, SCU_SYS_STATUS0, val, val);
        rsnd_mod_bset(mod, SCU_SYS_STATUS1, val, val);
}

static bool rsnd_src_record_error(struct rsnd_mod *mod)
{
        struct rsnd_src *src = rsnd_mod_to_src(mod);
        u32 val0, val1;
        bool ret = false;

        val0 = val1 = OUF_SRC(rsnd_mod_id(mod));

        /*
         * WORKAROUND
         *
         * ignore over flow error when rsnd_enable_sync_convert()
         */
        if (rsnd_enable_sync_convert(src))
                val0 = val0 & 0xffff;

        if ((rsnd_mod_read(mod, SCU_SYS_STATUS0) & val0) ||
            (rsnd_mod_read(mod, SCU_SYS_STATUS1) & val1)) {
                struct rsnd_src *src = rsnd_mod_to_src(mod);

                src->err++;
                ret = true;
        }

        return ret;
}

static int rsnd_src_start(struct rsnd_mod *mod,
                          struct rsnd_dai_stream *io,
                          struct rsnd_priv *priv)
{
        struct rsnd_src *src = rsnd_mod_to_src(mod);
        u32 val;

        /*
         * WORKAROUND
         *
         * Enable SRC output if you want to use sync convert together with DVC
         */
        val = (rsnd_io_to_mod_dvc(io) && !rsnd_enable_sync_convert(src)) ?
                0x01 : 0x11;

        rsnd_mod_write(mod, SRC_CTRL, val);

        return 0;
}

static int rsnd_src_stop(struct rsnd_mod *mod,
                         struct rsnd_dai_stream *io,
                         struct rsnd_priv *priv)
{
        /*
         * stop SRC output only
         * see rsnd_src_quit
         */
        rsnd_mod_write(mod, SRC_CTRL, 0x01);

        return 0;
}

static int rsnd_src_init(struct rsnd_mod *mod,
                         struct rsnd_dai_stream *io,
                         struct rsnd_priv *priv)
{
        struct rsnd_src *src = rsnd_mod_to_src(mod);

        rsnd_mod_power_on(mod);

        rsnd_src_activation(mod);

        rsnd_src_set_convert_rate(io, mod);

        rsnd_src_status_clear(mod);

        rsnd_src_irq_enable(mod);

        src->err = 0;

        /* reset sync convert_rate */
        src->sync.val = 0;

        return 0;
}

static int rsnd_src_quit(struct rsnd_mod *mod,
                         struct rsnd_dai_stream *io,
                         struct rsnd_priv *priv)
{
        struct rsnd_src *src = rsnd_mod_to_src(mod);
        struct device *dev = rsnd_priv_to_dev(priv);

        rsnd_src_irq_disable(mod);

        /* stop both out/in */
        rsnd_mod_write(mod, SRC_CTRL, 0);

        rsnd_src_halt(mod);

        rsnd_mod_power_off(mod);

        if (src->err)
                dev_warn(dev, "%s[%d] under/over flow err = %d\n",
                         rsnd_mod_name(mod), rsnd_mod_id(mod), src->err);

        src->convert_rate = 0;

        /* reset sync convert_rate */
        src->sync.val = 0;

        return 0;
}

static void __rsnd_src_interrupt(struct rsnd_mod *mod,
                                 struct rsnd_dai_stream *io)
{
        struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
        struct rsnd_src *src = rsnd_mod_to_src(mod);
        struct device *dev = rsnd_priv_to_dev(priv);

        spin_lock(&priv->lock);

        /* ignore all cases if not working */
        if (!rsnd_io_is_working(io))
                goto rsnd_src_interrupt_out;

        if (rsnd_src_record_error(mod)) {

                dev_dbg(dev, "%s[%d] restart\n",
                        rsnd_mod_name(mod), rsnd_mod_id(mod));

                rsnd_src_stop(mod, io, priv);
                rsnd_src_start(mod, io, priv);
        }

        if (src->err > 1024) {
                rsnd_src_irq_disable(mod);

                dev_warn(dev, "no more %s[%d] restart\n",
                         rsnd_mod_name(mod), rsnd_mod_id(mod));
        }

        rsnd_src_status_clear(mod);
rsnd_src_interrupt_out:

        spin_unlock(&priv->lock);
}

static irqreturn_t rsnd_src_interrupt(int irq, void *data)
{
        struct rsnd_mod *mod = data;

        rsnd_mod_interrupt(mod, __rsnd_src_interrupt);

        return IRQ_HANDLED;
}

static int rsnd_src_probe_(struct rsnd_mod *mod,
                           struct rsnd_dai_stream *io,
                           struct rsnd_priv *priv)
{
        struct rsnd_src *src = rsnd_mod_to_src(mod);
        struct device *dev = rsnd_priv_to_dev(priv);
        int irq = src->irq;
        int ret;

        if (irq > 0) {
                /*
                 * IRQ is not supported on non-DT
                 * see
                 *      rsnd_src_irq_enable()
                 */
                ret = devm_request_irq(dev, irq,
                                       rsnd_src_interrupt,
                                       IRQF_SHARED,
                                       dev_name(dev), mod);
                if (ret)
                        return ret;
        }

        src->dma = rsnd_dma_attach(io, mod, 0);
        if (IS_ERR(src->dma))
                return PTR_ERR(src->dma);

        return ret;
}

static int rsnd_src_pcm_new(struct rsnd_mod *mod,
                            struct rsnd_dai_stream *io,
                            struct snd_soc_pcm_runtime *rtd)
{
        struct rsnd_dai *rdai = rsnd_io_to_rdai(io);
        struct rsnd_mod *dvc = rsnd_io_to_mod_dvc(io);
        struct rsnd_src *src = rsnd_mod_to_src(mod);
        int ret;

        /*
         * enable SRC sync convert if possible
         */

        /*
         * SRC sync convert needs clock master
         */
        if (!rsnd_rdai_is_clk_master(rdai))
                return 0;

        /*
         * SRC In doesn't work if DVC was enabled
         */
        if (dvc && !rsnd_io_is_play(io))
                return 0;

        /*
         * enable sync convert
         */
        ret = rsnd_kctrl_new_s(mod, io, rtd,
                               rsnd_io_is_play(io) ?
                               "SRC Out Rate Switch" :
                               "SRC In Rate Switch",
                               rsnd_src_set_convert_rate,
                               &src->sen, 1);
        if (ret < 0)
                return ret;

        ret = rsnd_kctrl_new_s(mod, io, rtd,
                               rsnd_io_is_play(io) ?
                               "SRC Out Rate" :
                               "SRC In Rate",
                               rsnd_src_set_convert_rate,
                               &src->sync, 192000);

        return ret;
}

static struct rsnd_mod_ops rsnd_src_ops = {
        .name   = SRC_NAME,
        .dma_req = rsnd_src_dma_req,
        .probe  = rsnd_src_probe_,
        .init   = rsnd_src_init,
        .quit   = rsnd_src_quit,
        .start  = rsnd_src_start,
        .stop   = rsnd_src_stop,
        .hw_params = rsnd_src_hw_params,
        .pcm_new = rsnd_src_pcm_new,
};

struct rsnd_mod *rsnd_src_mod_get(struct rsnd_priv *priv, int id)
{
        if (WARN_ON(id < 0 || id >= rsnd_src_nr(priv)))
                id = 0;

        return rsnd_mod_get(rsnd_src_get(priv, id));
}

int rsnd_src_probe(struct rsnd_priv *priv)
{
        struct device_node *node;
        struct device_node *np;
        struct device *dev = rsnd_priv_to_dev(priv);
        struct rsnd_src *src;
        struct clk *clk;
        char name[RSND_SRC_NAME_SIZE];
        int i, nr, ret;

        /* This driver doesn't support Gen1 at this point */
        if (rsnd_is_gen1(priv))
                return 0;

        node = rsnd_src_of_node(priv);
        if (!node)
                return 0; /* not used is not error */

        nr = of_get_child_count(node);
        if (!nr) {
                ret = -EINVAL;
                goto rsnd_src_probe_done;
        }

        src     = devm_kzalloc(dev, sizeof(*src) * nr, GFP_KERNEL);
        if (!src) {
                ret = -ENOMEM;
                goto rsnd_src_probe_done;
        }

        priv->src_nr    = nr;
        priv->src       = src;

        i = 0;
        for_each_child_of_node(node, np) {
                src = rsnd_src_get(priv, i);

                snprintf(name, RSND_SRC_NAME_SIZE, "%s.%d",
                         SRC_NAME, i);

                src->irq = irq_of_parse_and_map(np, 0);
                if (!src->irq) {
                        ret = -EINVAL;
                        goto rsnd_src_probe_done;
                }

                clk = devm_clk_get(dev, name);
                if (IS_ERR(clk)) {
                        ret = PTR_ERR(clk);
                        goto rsnd_src_probe_done;
                }

                ret = rsnd_mod_init(priv, rsnd_mod_get(src),
                                    &rsnd_src_ops, clk, RSND_MOD_SRC, i);
                if (ret)
                        goto rsnd_src_probe_done;

                i++;
        }

        ret = 0;

rsnd_src_probe_done:
        of_node_put(node);

        return ret;
}

void rsnd_src_remove(struct rsnd_priv *priv)
{
        struct rsnd_src *src;
        int i;

        for_each_rsnd_src(src, priv, i) {
                rsnd_mod_quit(rsnd_mod_get(src));
        }
}