/*
 * Fifo-attached Serial Interface (FSI) support for SH7724
 *
 * Copyright (C) 2009 Renesas Solutions Corp.
 * Kuninori Morimoto <morimoto.kuninori@renesas.com>
 *
 * Based on ssi.c
 * Copyright (c) 2007 Manuel Lauss <mano@roarinelk.homelinux.net>
 *
 * 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 <linux/delay.h>
#include <linux/pm_runtime.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <sound/soc.h>
#include <sound/sh_fsi.h>

/* PortA/PortB register */
#define REG_DO_FMT      0x0000
#define REG_DOFF_CTL    0x0004
#define REG_DOFF_ST     0x0008
#define REG_DI_FMT      0x000C
#define REG_DIFF_CTL    0x0010
#define REG_DIFF_ST     0x0014
#define REG_CKG1        0x0018
#define REG_CKG2        0x001C
#define REG_DIDT        0x0020
#define REG_DODT        0x0024
#define REG_MUTE_ST     0x0028
#define REG_OUT_SEL     0x0030

/* master register */
#define MST_CLK_RST     0x0210
#define MST_SOFT_RST    0x0214
#define MST_FIFO_SZ     0x0218

/* core register (depend on FSI version) */
#define A_MST_CTLR      0x0180
#define B_MST_CTLR      0x01A0
#define CPU_INT_ST      0x01F4
#define CPU_IEMSK       0x01F8
#define CPU_IMSK        0x01FC
#define INT_ST          0x0200
#define IEMSK           0x0204
#define IMSK            0x0208

/* DO_FMT */
/* DI_FMT */
#define CR_BWS_24       (0x0 << 20) /* FSI2 */
#define CR_BWS_16       (0x1 << 20) /* FSI2 */
#define CR_BWS_20       (0x2 << 20) /* FSI2 */

#define CR_DTMD_PCM             (0x0 << 8) /* FSI2 */
#define CR_DTMD_SPDIF_PCM       (0x1 << 8) /* FSI2 */
#define CR_DTMD_SPDIF_STREAM    (0x2 << 8) /* FSI2 */

#define CR_MONO         (0x0 << 4)
#define CR_MONO_D       (0x1 << 4)
#define CR_PCM          (0x2 << 4)
#define CR_I2S          (0x3 << 4)
#define CR_TDM          (0x4 << 4)
#define CR_TDM_D        (0x5 << 4)

/* DOFF_CTL */
/* DIFF_CTL */
#define IRQ_HALF        0x00100000
#define FIFO_CLR        0x00000001

/* DOFF_ST */
#define ERR_OVER        0x00000010
#define ERR_UNDER       0x00000001
#define ST_ERR          (ERR_OVER | ERR_UNDER)

/* CKG1 */
#define ACKMD_MASK      0x00007000
#define BPFMD_MASK      0x00000700

/* A/B MST_CTLR */
#define BP      (1 << 4)        /* Fix the signal of Biphase output */
#define SE      (1 << 0)        /* Fix the master clock */

/* CLK_RST */
#define B_CLK           0x00000010
#define A_CLK           0x00000001

/* IO SHIFT / MACRO */
#define BI_SHIFT        12
#define BO_SHIFT        8
#define AI_SHIFT        4
#define AO_SHIFT        0
#define AB_IO(param, shift)     (param << shift)

/* SOFT_RST */
#define PBSR            (1 << 12) /* Port B Software Reset */
#define PASR            (1 <<  8) /* Port A Software Reset */
#define IR              (1 <<  4) /* Interrupt Reset */
#define FSISR           (1 <<  0) /* Software Reset */

/* OUT_SEL (FSI2) */
#define DMMD            (1 << 4) /* SPDIF output timing 0: Biphase only */
                                 /*                     1: Biphase and serial */

/* FIFO_SZ */
#define FIFO_SZ_MASK    0x7

#define FSI_RATES SNDRV_PCM_RATE_8000_96000

#define FSI_FMTS (SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S16_LE)

/*
 * FSI driver use below type name for variable
 *
 * xxx_len      : data length
 * xxx_width    : data width
 * xxx_offset   : data offset
 * xxx_num      : number of data
 */

/*
 *              struct
 */

struct fsi_stream {
        struct snd_pcm_substream *substream;

        int fifo_max_num;
        int chan_num;

        int buff_offset;
        int buff_len;
        int period_len;
        int period_num;

        int uerr_num;
        int oerr_num;
};

struct fsi_priv {
        void __iomem *base;
        struct fsi_master *master;

        struct fsi_stream playback;
        struct fsi_stream capture;

        long rate;
};

struct fsi_core {
        int ver;

        u32 int_st;
        u32 iemsk;
        u32 imsk;
        u32 a_mclk;
        u32 b_mclk;
};

struct fsi_master {
        void __iomem *base;
        int irq;
        struct fsi_priv fsia;
        struct fsi_priv fsib;
        struct fsi_core *core;
        struct sh_fsi_platform_info *info;
        spinlock_t lock;
};

/*
 *              basic read write function
 */

static void __fsi_reg_write(u32 reg, u32 data)
{
        /* valid data area is 24bit */
        data &= 0x00ffffff;

        __raw_writel(data, reg);
}

static u32 __fsi_reg_read(u32 reg)
{
        return __raw_readl(reg);
}

static void __fsi_reg_mask_set(u32 reg, u32 mask, u32 data)
{
        u32 val = __fsi_reg_read(reg);

        val &= ~mask;
        val |= data & mask;

        __fsi_reg_write(reg, val);
}

#define fsi_reg_write(p, r, d)\
        __fsi_reg_write((u32)(p->base + REG_##r), d)

#define fsi_reg_read(p, r)\
        __fsi_reg_read((u32)(p->base + REG_##r))

#define fsi_reg_mask_set(p, r, m, d)\
        __fsi_reg_mask_set((u32)(p->base + REG_##r), m, d)

#define fsi_master_read(p, r) _fsi_master_read(p, MST_##r)
#define fsi_core_read(p, r)   _fsi_master_read(p, p->core->r)
static u32 _fsi_master_read(struct fsi_master *master, u32 reg)
{
        u32 ret;
        unsigned long flags;

        spin_lock_irqsave(&master->lock, flags);
        ret = __fsi_reg_read((u32)(master->base + reg));
        spin_unlock_irqrestore(&master->lock, flags);

        return ret;
}

#define fsi_master_mask_set(p, r, m, d) _fsi_master_mask_set(p, MST_##r, m, d)
#define fsi_core_mask_set(p, r, m, d)  _fsi_master_mask_set(p, p->core->r, m, d)
static void _fsi_master_mask_set(struct fsi_master *master,
                               u32 reg, u32 mask, u32 data)
{
        unsigned long flags;

        spin_lock_irqsave(&master->lock, flags);
        __fsi_reg_mask_set((u32)(master->base + reg), mask, data);
        spin_unlock_irqrestore(&master->lock, flags);
}

/*
 *              basic function
 */

static struct fsi_master *fsi_get_master(struct fsi_priv *fsi)
{
        return fsi->master;
}

static int fsi_is_port_a(struct fsi_priv *fsi)
{
        return fsi->master->base == fsi->base;
}

static struct snd_soc_dai *fsi_get_dai(struct snd_pcm_substream *substream)
{
        struct snd_soc_pcm_runtime *rtd = substream->private_data;

        return  rtd->cpu_dai;
}

static struct fsi_priv *fsi_get_priv(struct snd_pcm_substream *substream)
{
        struct snd_soc_dai *dai = fsi_get_dai(substream);
        struct fsi_master *master = snd_soc_dai_get_drvdata(dai);

        if (dai->id == 0)
                return &master->fsia;
        else
                return &master->fsib;
}

static u32 fsi_get_info_flags(struct fsi_priv *fsi)
{
        int is_porta = fsi_is_port_a(fsi);
        struct fsi_master *master = fsi_get_master(fsi);

        return is_porta ? master->info->porta_flags :
                master->info->portb_flags;
}

static inline int fsi_stream_is_play(int stream)
{
        return stream == SNDRV_PCM_STREAM_PLAYBACK;
}

static inline int fsi_is_play(struct snd_pcm_substream *substream)
{
        return fsi_stream_is_play(substream->stream);
}

static inline struct fsi_stream *fsi_get_stream(struct fsi_priv *fsi,
                                                int is_play)
{
        return is_play ? &fsi->playback : &fsi->capture;
}

static int fsi_is_master_mode(struct fsi_priv *fsi, int is_play)
{
        u32 mode;
        u32 flags = fsi_get_info_flags(fsi);

        mode = is_play ? SH_FSI_OUT_SLAVE_MODE : SH_FSI_IN_SLAVE_MODE;

        /* return
         * 1 : master mode
         * 0 : slave mode
         */

        return (mode & flags) != mode;
}

static u32 fsi_get_port_shift(struct fsi_priv *fsi, int is_play)
{
        int is_porta = fsi_is_port_a(fsi);
        u32 shift;

        if (is_porta)
                shift = is_play ? AO_SHIFT : AI_SHIFT;
        else
                shift = is_play ? BO_SHIFT : BI_SHIFT;

        return shift;
}

static void fsi_stream_push(struct fsi_priv *fsi,
                            int is_play,
                            struct snd_pcm_substream *substream,
                            u32 buffer_len,
                            u32 period_len)
{
        struct fsi_stream *io = fsi_get_stream(fsi, is_play);

        io->substream   = substream;
        io->buff_len    = buffer_len;
        io->buff_offset = 0;
        io->period_len  = period_len;
        io->period_num  = 0;
        io->oerr_num    = -1; /* ignore 1st err */
        io->uerr_num    = -1; /* ignore 1st err */
}

static void fsi_stream_pop(struct fsi_priv *fsi, int is_play)
{
        struct fsi_stream *io = fsi_get_stream(fsi, is_play);
        struct snd_soc_dai *dai = fsi_get_dai(io->substream);


        if (io->oerr_num > 0)
                dev_err(dai->dev, "over_run = %d\n", io->oerr_num);

        if (io->uerr_num > 0)
                dev_err(dai->dev, "under_run = %d\n", io->uerr_num);

        io->substream   = NULL;
        io->buff_len    = 0;
        io->buff_offset = 0;
        io->period_len  = 0;
        io->period_num  = 0;
        io->oerr_num    = 0;
        io->uerr_num    = 0;
}

static int fsi_get_fifo_data_num(struct fsi_priv *fsi, int is_play)
{
        u32 status;
        struct fsi_stream *io = fsi_get_stream(fsi, is_play);
        int data_num;

        status = is_play ?
                fsi_reg_read(fsi, DOFF_ST) :
                fsi_reg_read(fsi, DIFF_ST);

        data_num = 0x1ff & (status >> 8);
        data_num *= io->chan_num;

        return data_num;
}

static int fsi_len2num(int len, int width)
{
        return len / width;
}

#define fsi_num2offset(a, b) fsi_num2len(a, b)
static int fsi_num2len(int num, int width)
{
        return num * width;
}

static int fsi_get_frame_width(struct fsi_priv *fsi, int is_play)
{
        struct fsi_stream *io = fsi_get_stream(fsi, is_play);
        struct snd_pcm_substream *substream = io->substream;
        struct snd_pcm_runtime *runtime = substream->runtime;

        return frames_to_bytes(runtime, 1) / io->chan_num;
}

static void fsi_count_fifo_err(struct fsi_priv *fsi)
{
        u32 ostatus = fsi_reg_read(fsi, DOFF_ST);
        u32 istatus = fsi_reg_read(fsi, DIFF_ST);

        if (ostatus & ERR_OVER)
                fsi->playback.oerr_num++;

        if (ostatus & ERR_UNDER)
                fsi->playback.uerr_num++;

        if (istatus & ERR_OVER)
                fsi->capture.oerr_num++;

        if (istatus & ERR_UNDER)
                fsi->capture.uerr_num++;

        fsi_reg_write(fsi, DOFF_ST, 0);
        fsi_reg_write(fsi, DIFF_ST, 0);
}

/*
 *              dma function
 */

static u8 *fsi_dma_get_area(struct fsi_priv *fsi, int stream)
{
        int is_play = fsi_stream_is_play(stream);
        struct fsi_stream *io = fsi_get_stream(fsi, is_play);

        return io->substream->runtime->dma_area + io->buff_offset;
}

static void fsi_dma_soft_push16(struct fsi_priv *fsi, int num)
{
        u16 *start;
        int i;

        start  = (u16 *)fsi_dma_get_area(fsi, SNDRV_PCM_STREAM_PLAYBACK);

        for (i = 0; i < num; i++)
                fsi_reg_write(fsi, DODT, ((u32)*(start + i) << 8));
}

static void fsi_dma_soft_pop16(struct fsi_priv *fsi, int num)
{
        u16 *start;
        int i;

        start  = (u16 *)fsi_dma_get_area(fsi, SNDRV_PCM_STREAM_CAPTURE);


        for (i = 0; i < num; i++)
                *(start + i) = (u16)(fsi_reg_read(fsi, DIDT) >> 8);
}

static void fsi_dma_soft_push32(struct fsi_priv *fsi, int num)
{
        u32 *start;
        int i;

        start  = (u32 *)fsi_dma_get_area(fsi, SNDRV_PCM_STREAM_PLAYBACK);


        for (i = 0; i < num; i++)
                fsi_reg_write(fsi, DODT, *(start + i));
}

static void fsi_dma_soft_pop32(struct fsi_priv *fsi, int num)
{
        u32 *start;
        int i;

        start  = (u32 *)fsi_dma_get_area(fsi, SNDRV_PCM_STREAM_CAPTURE);

        for (i = 0; i < num; i++)
                *(start + i) = fsi_reg_read(fsi, DIDT);
}

/*
 *              irq function
 */

static void fsi_irq_enable(struct fsi_priv *fsi, int is_play)
{
        u32 data = AB_IO(1, fsi_get_port_shift(fsi, is_play));
        struct fsi_master *master = fsi_get_master(fsi);

        fsi_core_mask_set(master, imsk,  data, data);
        fsi_core_mask_set(master, iemsk, data, data);
}

static void fsi_irq_disable(struct fsi_priv *fsi, int is_play)
{
        u32 data = AB_IO(1, fsi_get_port_shift(fsi, is_play));
        struct fsi_master *master = fsi_get_master(fsi);

        fsi_core_mask_set(master, imsk,  data, 0);
        fsi_core_mask_set(master, iemsk, data, 0);
}

static u32 fsi_irq_get_status(struct fsi_master *master)
{
        return fsi_core_read(master, int_st);
}

static void fsi_irq_clear_status(struct fsi_priv *fsi)
{
        u32 data = 0;
        struct fsi_master *master = fsi_get_master(fsi);

        data |= AB_IO(1, fsi_get_port_shift(fsi, 0));
        data |= AB_IO(1, fsi_get_port_shift(fsi, 1));

        /* clear interrupt factor */
        fsi_core_mask_set(master, int_st, data, 0);
}

/*
 *              SPDIF master clock function
 *
 * These functions are used later FSI2
 */
static void fsi_spdif_clk_ctrl(struct fsi_priv *fsi, int enable)
{
        struct fsi_master *master = fsi_get_master(fsi);
        u32 mask, val;

        if (master->core->ver < 2) {
                pr_err("fsi: register access err (%s)\n", __func__);
                return;
        }

        mask = BP | SE;
        val = enable ? mask : 0;

        fsi_is_port_a(fsi) ?
                fsi_core_mask_set(master, a_mclk, mask, val) :
                fsi_core_mask_set(master, b_mclk, mask, val);
}

/*
 *              ctrl function
 */

static void fsi_clk_ctrl(struct fsi_priv *fsi, int enable)
{
        u32 val = fsi_is_port_a(fsi) ? (1 << 0) : (1 << 4);
        struct fsi_master *master = fsi_get_master(fsi);

        if (enable)
                fsi_master_mask_set(master, CLK_RST, val, val);
        else
                fsi_master_mask_set(master, CLK_RST, val, 0);
}

static void fsi_fifo_init(struct fsi_priv *fsi,
                          int is_play,
                          struct snd_soc_dai *dai)
{
        struct fsi_master *master = fsi_get_master(fsi);
        struct fsi_stream *io = fsi_get_stream(fsi, is_play);
        u32 shift, i;

        /* get on-chip RAM capacity */
        shift = fsi_master_read(master, FIFO_SZ);
        shift >>= fsi_get_port_shift(fsi, is_play);
        shift &= FIFO_SZ_MASK;
        io->fifo_max_num = 256 << shift;
        dev_dbg(dai->dev, "fifo = %d words\n", io->fifo_max_num);

        /*
         * The maximum number of sample data varies depending
         * on the number of channels selected for the format.
         *
         * FIFOs are used in 4-channel units in 3-channel mode
         * and in 8-channel units in 5- to 7-channel mode
         * meaning that more FIFOs than the required size of DPRAM
         * are used.
         *
         * ex) if 256 words of DP-RAM is connected
         * 1 channel:  256 (256 x 1 = 256)
         * 2 channels: 128 (128 x 2 = 256)
         * 3 channels:  64 ( 64 x 3 = 192)
         * 4 channels:  64 ( 64 x 4 = 256)
         * 5 channels:  32 ( 32 x 5 = 160)
         * 6 channels:  32 ( 32 x 6 = 192)
         * 7 channels:  32 ( 32 x 7 = 224)
         * 8 channels:  32 ( 32 x 8 = 256)
         */
        for (i = 1; i < io->chan_num; i <<= 1)
                io->fifo_max_num >>= 1;
        dev_dbg(dai->dev, "%d channel %d store\n",
                io->chan_num, io->fifo_max_num);

        /*
         * set interrupt generation factor
         * clear FIFO
         */
        if (is_play) {
                fsi_reg_write(fsi,      DOFF_CTL, IRQ_HALF);
                fsi_reg_mask_set(fsi,   DOFF_CTL, FIFO_CLR, FIFO_CLR);
        } else {
                fsi_reg_write(fsi,      DIFF_CTL, IRQ_HALF);
                fsi_reg_mask_set(fsi,   DIFF_CTL, FIFO_CLR, FIFO_CLR);
        }
}

static void fsi_soft_all_reset(struct fsi_master *master)
{
        /* port AB reset */
        fsi_master_mask_set(master, SOFT_RST, PASR | PBSR, 0);
        mdelay(10);

        /* soft reset */
        fsi_master_mask_set(master, SOFT_RST, FSISR, 0);
        fsi_master_mask_set(master, SOFT_RST, FSISR, FSISR);
        mdelay(10);
}

static int fsi_fifo_data_ctrl(struct fsi_priv *fsi, int stream)
{
        struct snd_pcm_runtime *runtime;
        struct snd_pcm_substream *substream = NULL;
        int is_play = fsi_stream_is_play(stream);
        struct fsi_stream *io = fsi_get_stream(fsi, is_play);
        int data_residue_num;
        int data_num;
        int data_num_max;
        int ch_width;
        int over_period;
        void (*fn)(struct fsi_priv *fsi, int size);

        if (!fsi                        ||
            !io->substream              ||
            !io->substream->runtime)
                return -EINVAL;

        over_period     = 0;
        substream       = io->substream;
        runtime         = substream->runtime;

        /* FSI FIFO has limit.
         * So, this driver can not send periods data at a time
         */
        if (io->buff_offset >=
            fsi_num2offset(io->period_num + 1, io->period_len)) {

                over_period = 1;
                io->period_num = (io->period_num + 1) % runtime->periods;

                if (0 == io->period_num)
                        io->buff_offset = 0;
        }

        /* get 1 channel data width */
        ch_width = fsi_get_frame_width(fsi, is_play);

        /* get residue data number of alsa */
        data_residue_num = fsi_len2num(io->buff_len - io->buff_offset,
                                       ch_width);

        if (is_play) {
                /*
                 * for play-back
                 *
                 * data_num_max : number of FSI fifo free space
                 * data_num     : number of ALSA residue data
                 */
                data_num_max  = io->fifo_max_num * io->chan_num;
                data_num_max -= fsi_get_fifo_data_num(fsi, is_play);

                data_num = data_residue_num;

                switch (ch_width) {
                case 2:
                        fn = fsi_dma_soft_push16;
                        break;
                case 4:
                        fn = fsi_dma_soft_push32;
                        break;
                default:
                        return -EINVAL;
                }
        } else {
                /*
                 * for capture
                 *
                 * data_num_max : number of ALSA free space
                 * data_num     : number of data in FSI fifo
                 */
                data_num_max = data_residue_num;
                data_num     = fsi_get_fifo_data_num(fsi, is_play);

                switch (ch_width) {
                case 2:
                        fn = fsi_dma_soft_pop16;
                        break;
                case 4:
                        fn = fsi_dma_soft_pop32;
                        break;
                default:
                        return -EINVAL;
                }
        }

        data_num = min(data_num, data_num_max);

        fn(fsi, data_num);

        /* update buff_offset */
        io->buff_offset += fsi_num2offset(data_num, ch_width);

        if (over_period)
                snd_pcm_period_elapsed(substream);

        return 0;
}

static int fsi_data_pop(struct fsi_priv *fsi)
{
        return fsi_fifo_data_ctrl(fsi, SNDRV_PCM_STREAM_CAPTURE);
}

static int fsi_data_push(struct fsi_priv *fsi)
{
        return fsi_fifo_data_ctrl(fsi, SNDRV_PCM_STREAM_PLAYBACK);
}

static irqreturn_t fsi_interrupt(int irq, void *data)
{
        struct fsi_master *master = data;
        u32 int_st = fsi_irq_get_status(master);

        /* clear irq status */
        fsi_master_mask_set(master, SOFT_RST, IR, 0);
        fsi_master_mask_set(master, SOFT_RST, IR, IR);

        if (int_st & AB_IO(1, AO_SHIFT))
                fsi_data_push(&master->fsia);
        if (int_st & AB_IO(1, BO_SHIFT))
                fsi_data_push(&master->fsib);
        if (int_st & AB_IO(1, AI_SHIFT))
                fsi_data_pop(&master->fsia);
        if (int_st & AB_IO(1, BI_SHIFT))
                fsi_data_pop(&master->fsib);

        fsi_count_fifo_err(&master->fsia);
        fsi_count_fifo_err(&master->fsib);

        fsi_irq_clear_status(&master->fsia);
        fsi_irq_clear_status(&master->fsib);

        return IRQ_HANDLED;
}

/*
 *              dai ops
 */

static int fsi_dai_startup(struct snd_pcm_substream *substream,
                           struct snd_soc_dai *dai)
{
        struct fsi_priv *fsi = fsi_get_priv(substream);
        struct fsi_master *master = fsi_get_master(fsi);
        struct fsi_stream *io;
        u32 flags = fsi_get_info_flags(fsi);
        u32 fmt;
        u32 data;
        int is_play = fsi_is_play(substream);
        int is_master;

        io = fsi_get_stream(fsi, is_play);

        pm_runtime_get_sync(dai->dev);

        /* CKG1 */
        data = is_play ? (1 << 0) : (1 << 4);
        is_master = fsi_is_master_mode(fsi, is_play);
        if (is_master)
                fsi_reg_mask_set(fsi, CKG1, data, data);
        else
                fsi_reg_mask_set(fsi, CKG1, data, 0);

        /* clock inversion (CKG2) */
        data = 0;
        if (SH_FSI_LRM_INV & flags)
                data |= 1 << 12;
        if (SH_FSI_BRM_INV & flags)
                data |= 1 << 8;
        if (SH_FSI_LRS_INV & flags)
                data |= 1 << 4;
        if (SH_FSI_BRS_INV & flags)
                data |= 1 << 0;

        fsi_reg_write(fsi, CKG2, data);

        /* do fmt, di fmt */
        data = 0;
        fmt = is_play ? SH_FSI_GET_OFMT(flags) : SH_FSI_GET_IFMT(flags);
        switch (fmt) {
        case SH_FSI_FMT_MONO:
                data = CR_MONO;
                io->chan_num = 1;
                break;
        case SH_FSI_FMT_MONO_DELAY:
                data = CR_MONO_D;
                io->chan_num = 1;
                break;
        case SH_FSI_FMT_PCM:
                data = CR_PCM;
                io->chan_num = 2;
                break;
        case SH_FSI_FMT_I2S:
                data = CR_I2S;
                io->chan_num = 2;
                break;
        case SH_FSI_FMT_TDM:
                io->chan_num = is_play ?
                        SH_FSI_GET_CH_O(flags) : SH_FSI_GET_CH_I(flags);
                data = CR_TDM | (io->chan_num - 1);
                break;
        case SH_FSI_FMT_TDM_DELAY:
                io->chan_num = is_play ?
                        SH_FSI_GET_CH_O(flags) : SH_FSI_GET_CH_I(flags);
                data = CR_TDM_D | (io->chan_num - 1);
                break;
        case SH_FSI_FMT_SPDIF:
                if (master->core->ver < 2) {
                        dev_err(dai->dev, "This FSI can not use SPDIF\n");
                        return -EINVAL;
                }
                data = CR_BWS_16 | CR_DTMD_SPDIF_PCM | CR_PCM;
                io->chan_num = 2;
                fsi_spdif_clk_ctrl(fsi, 1);
                fsi_reg_mask_set(fsi, OUT_SEL, DMMD, DMMD);
                break;
        default:
                dev_err(dai->dev, "unknown format.\n");
                return -EINVAL;
        }
        is_play ?
                fsi_reg_write(fsi, DO_FMT, data) :
                fsi_reg_write(fsi, DI_FMT, data);

        /* irq clear */
        fsi_irq_disable(fsi, is_play);
        fsi_irq_clear_status(fsi);

        /* fifo init */
        fsi_fifo_init(fsi, is_play, dai);

        return 0;
}

static void fsi_dai_shutdown(struct snd_pcm_substream *substream,
                             struct snd_soc_dai *dai)
{
        struct fsi_priv *fsi = fsi_get_priv(substream);
        int is_play = fsi_is_play(substream);
        struct fsi_master *master = fsi_get_master(fsi);
        int (*set_rate)(struct device *dev, int is_porta, int rate, int enable);

        fsi_irq_disable(fsi, is_play);
        fsi_clk_ctrl(fsi, 0);

        set_rate = master->info->set_rate;
        if (set_rate && fsi->rate)
                set_rate(dai->dev, fsi_is_port_a(fsi), fsi->rate, 0);
        fsi->rate = 0;

        pm_runtime_put_sync(dai->dev);
}

static int fsi_dai_trigger(struct snd_pcm_substream *substream, int cmd,
                           struct snd_soc_dai *dai)
{
        struct fsi_priv *fsi = fsi_get_priv(substream);
        struct snd_pcm_runtime *runtime = substream->runtime;
        int is_play = fsi_is_play(substream);
        int ret = 0;

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
                fsi_stream_push(fsi, is_play, substream,
                                frames_to_bytes(runtime, runtime->buffer_size),
                                frames_to_bytes(runtime, runtime->period_size));
                ret = is_play ? fsi_data_push(fsi) : fsi_data_pop(fsi);
                fsi_irq_enable(fsi, is_play);
                break;
        case SNDRV_PCM_TRIGGER_STOP:
                fsi_irq_disable(fsi, is_play);
                fsi_stream_pop(fsi, is_play);
                break;
        }

        return ret;
}

static int fsi_dai_hw_params(struct snd_pcm_substream *substream,
                             struct snd_pcm_hw_params *params,
                             struct snd_soc_dai *dai)
{
        struct fsi_priv *fsi = fsi_get_priv(substream);
        struct fsi_master *master = fsi_get_master(fsi);
        int (*set_rate)(struct device *dev, int is_porta, int rate, int enable);
        int fsi_ver = master->core->ver;
        long rate = params_rate(params);
        int ret;

        set_rate = master->info->set_rate;
        if (!set_rate)
                return 0;

        ret = set_rate(dai->dev, fsi_is_port_a(fsi), rate, 1);
        if (ret < 0) /* error */
                return ret;

        fsi->rate = rate;
        if (ret > 0) {
                u32 data = 0;

                switch (ret & SH_FSI_ACKMD_MASK) {
                default:
                        /* FALL THROUGH */
                case SH_FSI_ACKMD_512:
                        data |= (0x0 << 12);
                        break;
                case SH_FSI_ACKMD_256:
                        data |= (0x1 << 12);
                        break;
                case SH_FSI_ACKMD_128:
                        data |= (0x2 << 12);
                        break;
                case SH_FSI_ACKMD_64:
                        data |= (0x3 << 12);
                        break;
                case SH_FSI_ACKMD_32:
                        if (fsi_ver < 2)
                                dev_err(dai->dev, "unsupported ACKMD\n");
                        else
                                data |= (0x4 << 12);
                        break;
                }

                switch (ret & SH_FSI_BPFMD_MASK) {
                default:
                        /* FALL THROUGH */
                case SH_FSI_BPFMD_32:
                        data |= (0x0 << 8);
                        break;
                case SH_FSI_BPFMD_64:
                        data |= (0x1 << 8);
                        break;
                case SH_FSI_BPFMD_128:
                        data |= (0x2 << 8);
                        break;
                case SH_FSI_BPFMD_256:
                        data |= (0x3 << 8);
                        break;
                case SH_FSI_BPFMD_512:
                        data |= (0x4 << 8);
                        break;
                case SH_FSI_BPFMD_16:
                        if (fsi_ver < 2)
                                dev_err(dai->dev, "unsupported ACKMD\n");
                        else
                                data |= (0x7 << 8);
                        break;
                }

                fsi_reg_mask_set(fsi, CKG1, (ACKMD_MASK | BPFMD_MASK) , data);
                udelay(10);
                fsi_clk_ctrl(fsi, 1);
                ret = 0;
        }

        return ret;

}

static struct snd_soc_dai_ops fsi_dai_ops = {
        .startup        = fsi_dai_startup,
        .shutdown       = fsi_dai_shutdown,
        .trigger        = fsi_dai_trigger,
        .hw_params      = fsi_dai_hw_params,
};

/*
 *              pcm ops
 */

static struct snd_pcm_hardware fsi_pcm_hardware = {
        .info =         SNDRV_PCM_INFO_INTERLEAVED      |
                        SNDRV_PCM_INFO_MMAP             |
                        SNDRV_PCM_INFO_MMAP_VALID       |
                        SNDRV_PCM_INFO_PAUSE,
        .formats                = FSI_FMTS,
        .rates                  = FSI_RATES,
        .rate_min               = 8000,
        .rate_max               = 192000,
        .channels_min           = 1,
        .channels_max           = 2,
        .buffer_bytes_max       = 64 * 1024,
        .period_bytes_min       = 32,
        .period_bytes_max       = 8192,
        .periods_min            = 1,
        .periods_max            = 32,

        .fifo_size              = 256,
};

static int fsi_pcm_open(struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        int ret = 0;

        snd_soc_set_runtime_hwparams(substream, &fsi_pcm_hardware);

        ret = snd_pcm_hw_constraint_integer(runtime,
                                            SNDRV_PCM_HW_PARAM_PERIODS);

        return ret;
}

static int fsi_hw_params(struct snd_pcm_substream *substream,
                         struct snd_pcm_hw_params *hw_params)
{
        return snd_pcm_lib_malloc_pages(substream,
                                        params_buffer_bytes(hw_params));
}

static int fsi_hw_free(struct snd_pcm_substream *substream)
{
        return snd_pcm_lib_free_pages(substream);
}

static snd_pcm_uframes_t fsi_pointer(struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct fsi_priv *fsi = fsi_get_priv(substream);
        struct fsi_stream *io = fsi_get_stream(fsi, fsi_is_play(substream));
        long location;

        location = (io->buff_offset - 1);
        if (location < 0)
                location = 0;

        return bytes_to_frames(runtime, location);
}

static struct snd_pcm_ops fsi_pcm_ops = {
        .open           = fsi_pcm_open,
        .ioctl          = snd_pcm_lib_ioctl,
        .hw_params      = fsi_hw_params,
        .hw_free        = fsi_hw_free,
        .pointer        = fsi_pointer,
};

/*
 *              snd_soc_platform
 */

#define PREALLOC_BUFFER         (32 * 1024)
#define PREALLOC_BUFFER_MAX     (32 * 1024)

static void fsi_pcm_free(struct snd_pcm *pcm)
{
        snd_pcm_lib_preallocate_free_for_all(pcm);
}

static int fsi_pcm_new(struct snd_card *card,
                       struct snd_soc_dai *dai,
                       struct snd_pcm *pcm)
{
        /*
         * dont use SNDRV_DMA_TYPE_DEV, since it will oops the SH kernel
         * in MMAP mode (i.e. aplay -M)
         */
        return snd_pcm_lib_preallocate_pages_for_all(
                pcm,
                SNDRV_DMA_TYPE_CONTINUOUS,
                snd_dma_continuous_data(GFP_KERNEL),
                PREALLOC_BUFFER, PREALLOC_BUFFER_MAX);
}

/*
 *              alsa struct
 */

static struct snd_soc_dai_driver fsi_soc_dai[] = {
        {
                .name                   = "fsia-dai",
                .playback = {
                        .rates          = FSI_RATES,
                        .formats        = FSI_FMTS,
                        .channels_min   = 1,
                        .channels_max   = 8,
                },
                .capture = {
                        .rates          = FSI_RATES,
                        .formats        = FSI_FMTS,
                        .channels_min   = 1,
                        .channels_max   = 8,
                },
                .ops = &fsi_dai_ops,
        },
        {
                .name                   = "fsib-dai",
                .playback = {
                        .rates          = FSI_RATES,
                        .formats        = FSI_FMTS,
                        .channels_min   = 1,
                        .channels_max   = 8,
                },
                .capture = {
                        .rates          = FSI_RATES,
                        .formats        = FSI_FMTS,
                        .channels_min   = 1,
                        .channels_max   = 8,
                },
                .ops = &fsi_dai_ops,
        },
};

static struct snd_soc_platform_driver fsi_soc_platform = {
        .ops            = &fsi_pcm_ops,
        .pcm_new        = fsi_pcm_new,
        .pcm_free       = fsi_pcm_free,
};

/*
 *              platform function
 */

static int fsi_probe(struct platform_device *pdev)
{
        struct fsi_master *master;
        const struct platform_device_id *id_entry;
        struct resource *res;
        unsigned int irq;
        int ret;

        id_entry = pdev->id_entry;
        if (!id_entry) {
                dev_err(&pdev->dev, "unknown fsi device\n");
                return -ENODEV;
        }

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        irq = platform_get_irq(pdev, 0);
        if (!res || (int)irq <= 0) {
                dev_err(&pdev->dev, "Not enough FSI platform resources.\n");
                ret = -ENODEV;
                goto exit;
        }

        master = kzalloc(sizeof(*master), GFP_KERNEL);
        if (!master) {
                dev_err(&pdev->dev, "Could not allocate master\n");
                ret = -ENOMEM;
                goto exit;
        }

        master->base = ioremap_nocache(res->start, resource_size(res));
        if (!master->base) {
                ret = -ENXIO;
                dev_err(&pdev->dev, "Unable to ioremap FSI registers.\n");
                goto exit_kfree;
        }

        /* master setting */
        master->irq             = irq;
        master->info            = pdev->dev.platform_data;
        master->core            = (struct fsi_core *)id_entry->driver_data;
        spin_lock_init(&master->lock);

        /* FSI A setting */
        master->fsia.base       = master->base;
        master->fsia.master     = master;

        /* FSI B setting */
        master->fsib.base       = master->base + 0x40;
        master->fsib.master     = master;

        pm_runtime_enable(&pdev->dev);
        pm_runtime_resume(&pdev->dev);
        dev_set_drvdata(&pdev->dev, master);

        fsi_soft_all_reset(master);

        ret = request_irq(irq, &fsi_interrupt, IRQF_DISABLED,
                          id_entry->name, master);
        if (ret) {
                dev_err(&pdev->dev, "irq request err\n");
                goto exit_iounmap;
        }

        ret = snd_soc_register_platform(&pdev->dev, &fsi_soc_platform);
        if (ret < 0) {
                dev_err(&pdev->dev, "cannot snd soc register\n");
                goto exit_free_irq;
        }

        return snd_soc_register_dais(&pdev->dev, fsi_soc_dai, ARRAY_SIZE(fsi_soc_dai));

exit_free_irq:
        free_irq(irq, master);
exit_iounmap:
        iounmap(master->base);
        pm_runtime_disable(&pdev->dev);
exit_kfree:
        kfree(master);
        master = NULL;
exit:
        return ret;
}

static int fsi_remove(struct platform_device *pdev)
{
        struct fsi_master *master;

        master = dev_get_drvdata(&pdev->dev);

        snd_soc_unregister_dais(&pdev->dev, ARRAY_SIZE(fsi_soc_dai));
        snd_soc_unregister_platform(&pdev->dev);

        pm_runtime_disable(&pdev->dev);

        free_irq(master->irq, master);

        iounmap(master->base);
        kfree(master);

        return 0;
}

static int fsi_runtime_nop(struct device *dev)
{
        /* Runtime PM callback shared between ->runtime_suspend()
         * and ->runtime_resume(). Simply returns success.
         *
         * This driver re-initializes all registers after
         * pm_runtime_get_sync() anyway so there is no need
         * to save and restore registers here.
         */
        return 0;
}

static struct dev_pm_ops fsi_pm_ops = {
        .runtime_suspend        = fsi_runtime_nop,
        .runtime_resume         = fsi_runtime_nop,
};

static struct fsi_core fsi1_core = {
        .ver    = 1,

        /* Interrupt */
        .int_st = INT_ST,
        .iemsk  = IEMSK,
        .imsk   = IMSK,
};

static struct fsi_core fsi2_core = {
        .ver    = 2,

        /* Interrupt */
        .int_st = CPU_INT_ST,
        .iemsk  = CPU_IEMSK,
        .imsk   = CPU_IMSK,
        .a_mclk = A_MST_CTLR,
        .b_mclk = B_MST_CTLR,
};

static struct platform_device_id fsi_id_table[] = {
        { "sh_fsi",     (kernel_ulong_t)&fsi1_core },
        { "sh_fsi2",    (kernel_ulong_t)&fsi2_core },
        {},
};
MODULE_DEVICE_TABLE(platform, fsi_id_table);

static struct platform_driver fsi_driver = {
        .driver         = {
                .name   = "fsi-pcm-audio",
                .pm     = &fsi_pm_ops,
        },
        .probe          = fsi_probe,
        .remove         = fsi_remove,
        .id_table       = fsi_id_table,
};

static int __init fsi_mobile_init(void)
{
        return platform_driver_register(&fsi_driver);
}

static void __exit fsi_mobile_exit(void)
{
        platform_driver_unregister(&fsi_driver);
}

module_init(fsi_mobile_init);
module_exit(fsi_mobile_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("SuperH onchip FSI audio driver");
MODULE_AUTHOR("Kuninori Morimoto <morimoto.kuninori@renesas.com>");