// SPDX-License-Identifier: GPL-2.0
//
// Renesas R-Car SRC support
//
// Copyright (C) 2013 Renesas Solutions Corp.
// Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>

/*
 * You can use Synchronous Sampling Rate Convert (if no DVC)
 *
 *      amixer set "SRC Out Rate" on
 *      aplay xxx.wav &
 *      amixer set "SRC Out Rate" 96000 // convert rate to 96000Hz
 *      amixer set "SRC Out Rate" 22050 // convert rate to 22050Hz
 */

/*
 * you can enable below define if you don't need
 * SSI interrupt status debug message when debugging
 * see rsnd_print_irq_status()
 *
 * #define RSND_DEBUG_NO_IRQ_STATUS 1
 */

#include <linux/of_irq.h>
#include "rsnd.h"

#define SRC_NAME "src"

/* 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 current_sync_rate;
        int irq;
};

#define RSND_SRC_NAME_SIZE 16

#define rsnd_src_get(priv, id) ((struct rsnd_src *)(priv->src) + id)
#define rsnd_src_nr(priv) ((priv)->src_nr)
#define rsnd_src_sync_is_enabled(mod) (rsnd_mod_to_src(mod)->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 <-> +-----+          +-----+         +-------+
 * ...
 *
 */

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),
                                        SRC_NAME, mod,
                                        is_play ? "rx" : "tx");
}

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

        if (!runtime)
                return 0;

        if (!rsnd_src_sync_is_enabled(mod))
                return rsnd_io_converted_rate(io);

        convert_rate = src->current_sync_rate;

        if (!convert_rate)
                convert_rate = rsnd_io_converted_rate(io);

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

        return convert_rate;
}

unsigned int rsnd_src_get_rate(struct rsnd_priv *priv,
                               struct rsnd_dai_stream *io,
                               int is_in)
{
        struct rsnd_mod *src_mod = rsnd_io_to_mod_src(io);
        struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
        unsigned int rate = 0;
        int is_play = rsnd_io_is_play(io);

        /*
         * Playback
         * runtime_rate -> [SRC] -> convert_rate
         *
         * Capture
         * convert_rate -> [SRC] -> runtime_rate
         */

        if (is_play == is_in)
                return runtime->rate;

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

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

        return rate;
}

static const u32 bsdsr_table_pattern1[] = {
        0x01800000, /* 6 - 1/6 */
        0x01000000, /* 6 - 1/4 */
        0x00c00000, /* 6 - 1/3 */
        0x00800000, /* 6 - 1/2 */
        0x00600000, /* 6 - 2/3 */
        0x00400000, /* 6 - 1   */
};

static const u32 bsdsr_table_pattern2[] = {
        0x02400000, /* 6 - 1/6 */
        0x01800000, /* 6 - 1/4 */
        0x01200000, /* 6 - 1/3 */
        0x00c00000, /* 6 - 1/2 */
        0x00900000, /* 6 - 2/3 */
        0x00600000, /* 6 - 1   */
};

static const u32 bsisr_table[] = {
        0x00100060, /* 6 - 1/6 */
        0x00100040, /* 6 - 1/4 */
        0x00100030, /* 6 - 1/3 */
        0x00100020, /* 6 - 1/2 */
        0x00100020, /* 6 - 2/3 */
        0x00100020, /* 6 - 1   */
};

static const u32 chan288888[] = {
        0x00000006, /* 1 to 2 */
        0x000001fe, /* 1 to 8 */
        0x000001fe, /* 1 to 8 */
        0x000001fe, /* 1 to 8 */
        0x000001fe, /* 1 to 8 */
        0x000001fe, /* 1 to 8 */
};

static const u32 chan244888[] = {
        0x00000006, /* 1 to 2 */
        0x0000001e, /* 1 to 4 */
        0x0000001e, /* 1 to 4 */
        0x000001fe, /* 1 to 8 */
        0x000001fe, /* 1 to 8 */
        0x000001fe, /* 1 to 8 */
};

static const u32 chan222222[] = {
        0x00000006, /* 1 to 2 */
        0x00000006, /* 1 to 2 */
        0x00000006, /* 1 to 2 */
        0x00000006, /* 1 to 2 */
        0x00000006, /* 1 to 2 */
        0x00000006, /* 1 to 2 */
};

static void rsnd_src_set_convert_rate(struct rsnd_dai_stream *io,
                                      struct rsnd_mod *mod)
{
        struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
        struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
        struct rsnd_src *src = rsnd_mod_to_src(mod);
        u32 fin, fout, new_rate;
        int inc, cnt, rate;
        u64 base, val;

        if (!runtime)
                return;

        if (!rsnd_src_sync_is_enabled(mod))
                return;

        fin     = rsnd_src_get_in_rate(priv, io);
        fout    = rsnd_src_get_out_rate(priv, io);

        new_rate = src->sync.val;

        if (!new_rate)
                new_rate = fout;

        /* Do nothing if no diff */
        if (new_rate == src->current_sync_rate)
                return;

        /*
         * SRCm_IFSVR::INTIFS can change within 1%
         * see
         *      SRCm_IFSVR::INTIFS Note
         */
        inc = fout / 100;
        cnt = abs(new_rate - fout) / inc;
        if (fout > new_rate)
                inc *= -1;

        /*
         * After start running SRC, we can update only SRC_IFSVR
         * for Synchronous Mode
         */
        base = (u64)0x0400000 * fin;
        rate  = fout;
        for (int i = 0; i < cnt; i++) {
                val   = base;
                rate += inc;
                do_div(val, rate);

                rsnd_mod_write(mod, SRC_IFSVR, val);
        }
        val   = base;
        do_div(val, new_rate);

        rsnd_mod_write(mod, SRC_IFSVR, val);

        /* update current_sync_rate */
        src->current_sync_rate = new_rate;
}

static void rsnd_src_init_convert_rate(struct rsnd_dai_stream *io,
                                       struct rsnd_mod *mod)
{
        struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
        struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
        struct device *dev = rsnd_priv_to_dev(priv);
        int is_play = rsnd_io_is_play(io);
        int use_src = 0;
        u32 fin, fout;
        u32 ifscr, adinr;
        u32 cr, route;
        u32 i_busif, o_busif, tmp;
        const u32 *bsdsr_table;
        const u32 *chptn;
        uint ratio;
        int chan;
        int idx;

        if (!runtime)
                return;

        fin  = rsnd_src_get_in_rate(priv, io);
        fout = rsnd_src_get_out_rate(priv, io);

        chan = rsnd_runtime_channel_original(io);

        /* 6 - 1/6 are very enough ratio for SRC_BSDSR */
        if (fin == fout)
                ratio = 0;
        else if (fin > fout)
                ratio = 100 * fin / fout;
        else
                ratio = 100 * fout / fin;

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

        use_src = (fin != fout) | rsnd_src_sync_is_enabled(mod);

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

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

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

        /*
         * SRC_BSDSR / SRC_BSISR
         *
         * see
         *      Combination of Register Setting Related to
         *      FSO/FSI Ratio and Channel, Latency
         */
        switch (rsnd_mod_id(mod)) {
        case 0:
                chptn           = chan288888;
                bsdsr_table     = bsdsr_table_pattern1;
                break;
        case 1:
        case 3:
        case 4:
                chptn           = chan244888;
                bsdsr_table     = bsdsr_table_pattern1;
                break;
        case 2:
        case 9:
                chptn           = chan222222;
                bsdsr_table     = bsdsr_table_pattern1;
                break;
        case 5:
        case 6:
        case 7:
        case 8:
                chptn           = chan222222;
                bsdsr_table     = bsdsr_table_pattern2;
                break;
        default:
                goto convert_rate_err;
        }

        /*
         * E3 need to overwrite
         */
        if (rsnd_is_gen3_e3(priv))
                switch (rsnd_mod_id(mod)) {
                case 0:
                case 4:
                        chptn   = chan222222;
                }

        for (idx = 0; idx < ARRAY_SIZE(chan222222); idx++)
                if (chptn[idx] & (1 << chan))
                        break;

        if (chan > 8 ||
            idx >= ARRAY_SIZE(chan222222))
                goto convert_rate_err;

        /* BUSIF_MODE */
        tmp = rsnd_get_busif_shift(io, mod);
        i_busif = ( is_play ? tmp : 0) | 1;
        o_busif = (!is_play ? tmp : 0) | 1;

        rsnd_mod_write(mod, SRC_ROUTE_MODE0, route);

        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_SRCCR, cr);
        rsnd_mod_write(mod, SRC_BSDSR, bsdsr_table[idx]);
        rsnd_mod_write(mod, SRC_BSISR, bsisr_table[idx]);
        rsnd_mod_write(mod, SRC_SRCIR, 0);      /* cancel initialize */

        rsnd_mod_write(mod, SRC_I_BUSIF_MODE, i_busif);
        rsnd_mod_write(mod, SRC_O_BUSIF_MODE, o_busif);

        rsnd_mod_write(mod, SRC_BUSIF_DALIGN, rsnd_get_dalign(mod, io));

        rsnd_adg_set_src_timesel_gen2(mod, io, fin, fout);

        /* update SRC_IFSVR */
        rsnd_src_set_convert_rate(io, mod);

        return;

convert_rate_err:
        dev_err(dev, "unknown BSDSR/BSDIR settings\n");
}

static int rsnd_src_irq(struct rsnd_mod *mod,
                        struct rsnd_dai_stream *io,
                        struct rsnd_priv *priv,
                        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_src_sync_is_enabled()
         */
        if (rsnd_src_sync_is_enabled(mod))
                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);

        return 0;
}

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

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

static bool rsnd_src_error_occurred(struct rsnd_mod *mod)
{
        struct rsnd_priv *priv = rsnd_mod_to_priv(mod);
        struct device *dev = rsnd_priv_to_dev(priv);
        u32 val0, val1;
        u32 status0, status1;
        bool ret = false;

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

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

        status0 = rsnd_mod_read(mod, SCU_SYS_STATUS0);
        status1 = rsnd_mod_read(mod, SCU_SYS_STATUS1);
        if ((status0 & val0) || (status1 & val1)) {
                rsnd_print_irq_status(dev, "%s err status : 0x%08x, 0x%08x\n",
                                      rsnd_mod_name(mod), status0, status1);

                ret = true;
        }

        return ret;
}

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

        /*
         * WORKAROUND
         *
         * Enable SRC output if you want to use sync convert together with DVC
         */
        val = (rsnd_io_to_mod_dvc(io) && !rsnd_src_sync_is_enabled(mod)) ?
                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)
{
        rsnd_mod_write(mod, SRC_CTRL, 0);

        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);
        int ret;

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

        ret = rsnd_mod_power_on(mod);
        if (ret < 0)
                return ret;

        rsnd_src_activation(mod);

        rsnd_src_init_convert_rate(io, mod);

        rsnd_src_status_clear(mod);

        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);

        rsnd_src_halt(mod);

        rsnd_mod_power_off(mod);

        /* reset sync convert_rate */
        src->sync.val           =
        src->current_sync_rate  = 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);
        bool stop = false;

        scoped_guard(spinlock, &priv->lock) {
                /* ignore all cases if not working */
                if (!rsnd_io_is_working(io))
                        break;

                if (rsnd_src_error_occurred(mod))
                        stop = true;

                rsnd_src_status_clear(mod);
        }

        if (stop)
                snd_pcm_stop_xrun(io->substream);
}

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_kctrl_accept_runtime(struct rsnd_dai_stream *io)
{
        struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);

        if (!runtime) {
                struct rsnd_priv *priv = rsnd_io_to_priv(io);
                struct device *dev = rsnd_priv_to_dev(priv);

                dev_warn(dev, "\"SRC Out Rate\" can use during running\n");

                return 0;
        }

        return 1;
}

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()
                 */
                ret = devm_request_irq(dev, irq,
                                       rsnd_src_interrupt,
                                       IRQF_SHARED,
                                       dev_name(dev), mod);
                if (ret)
                        return ret;
        }

        ret = rsnd_dma_attach(io, mod, &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_src *src = rsnd_mod_to_src(mod);
        int ret;

        /*
         * enable SRC sync convert if possible
         */

        /*
         * It can't use SRC Synchronous convert
         * when Capture if it uses CMD
         */
        if (rsnd_io_to_mod_cmd(io) && !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_kctrl_accept_anytime,
                               rsnd_src_init_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_kctrl_accept_runtime,
                               rsnd_src_set_convert_rate,
                               &src->sync, 192000);

        return ret;
}

#ifdef CONFIG_DEBUG_FS
static void rsnd_src_debug_info(struct seq_file *m,
                                struct rsnd_dai_stream *io,
                                struct rsnd_mod *mod)
{
        rsnd_debugfs_mod_reg_show(m, mod, RSND_BASE_SCU,
                                  rsnd_mod_id(mod) * 0x20, 0x20);
        seq_puts(m, "\n");
        rsnd_debugfs_mod_reg_show(m, mod, RSND_BASE_SCU,
                                  0x1c0, 0x20);
        seq_puts(m, "\n");
        rsnd_debugfs_mod_reg_show(m, mod, RSND_BASE_SCU,
                                  0x200 + rsnd_mod_id(mod) * 0x40, 0x40);
}
#define DEBUG_INFO .debug_info = rsnd_src_debug_info
#else
#define DEBUG_INFO
#endif

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,
        .irq            = rsnd_src_irq,
        .pcm_new        = rsnd_src_pcm_new,
        .get_status     = rsnd_mod_get_status,
        DEBUG_INFO
};

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 *dev = rsnd_priv_to_dev(priv);
        struct rsnd_src *src;
        struct clk *clk;
        char name[RSND_SRC_NAME_SIZE];
        int i, nr, ret;

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

        nr = rsnd_node_count(priv, node, SRC_NAME);
        if (!nr) {
                ret = -EINVAL;
                goto rsnd_src_probe_done;
        }

        src     = devm_kcalloc(dev, nr, sizeof(*src), 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_scoped(node, np) {
                if (!of_device_is_available(np))
                        goto skip;

                i = rsnd_node_fixed_index(dev, np, SRC_NAME, i);
                if (i < 0) {
                        ret = -EINVAL;
                        goto rsnd_src_probe_done;
                }

                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;

skip:
                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));
        }
}