/*
 * omap-mcbsp.c  --  OMAP ALSA SoC DAI driver using McBSP port
 *
 * Copyright (C) 2008 Nokia Corporation
 *
 * Contact: Jarkko Nikula <jarkko.nikula@bitmer.com>
 *          Peter Ujfalusi <peter.ujfalusi@ti.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.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/initval.h>
#include <sound/soc.h>
#include <sound/dmaengine_pcm.h>

#include "omap-mcbsp-priv.h"
#include "omap-mcbsp.h"
#include "sdma-pcm.h"

#define OMAP_MCBSP_RATES        (SNDRV_PCM_RATE_8000_96000)

enum {
        OMAP_MCBSP_WORD_8 = 0,
        OMAP_MCBSP_WORD_12,
        OMAP_MCBSP_WORD_16,
        OMAP_MCBSP_WORD_20,
        OMAP_MCBSP_WORD_24,
        OMAP_MCBSP_WORD_32,
};

static void omap_mcbsp_dump_reg(struct omap_mcbsp *mcbsp)
{
        dev_dbg(mcbsp->dev, "**** McBSP%d regs ****\n", mcbsp->id);
        dev_dbg(mcbsp->dev, "DRR2:  0x%04x\n", MCBSP_READ(mcbsp, DRR2));
        dev_dbg(mcbsp->dev, "DRR1:  0x%04x\n", MCBSP_READ(mcbsp, DRR1));
        dev_dbg(mcbsp->dev, "DXR2:  0x%04x\n", MCBSP_READ(mcbsp, DXR2));
        dev_dbg(mcbsp->dev, "DXR1:  0x%04x\n", MCBSP_READ(mcbsp, DXR1));
        dev_dbg(mcbsp->dev, "SPCR2: 0x%04x\n", MCBSP_READ(mcbsp, SPCR2));
        dev_dbg(mcbsp->dev, "SPCR1: 0x%04x\n", MCBSP_READ(mcbsp, SPCR1));
        dev_dbg(mcbsp->dev, "RCR2:  0x%04x\n", MCBSP_READ(mcbsp, RCR2));
        dev_dbg(mcbsp->dev, "RCR1:  0x%04x\n", MCBSP_READ(mcbsp, RCR1));
        dev_dbg(mcbsp->dev, "XCR2:  0x%04x\n", MCBSP_READ(mcbsp, XCR2));
        dev_dbg(mcbsp->dev, "XCR1:  0x%04x\n", MCBSP_READ(mcbsp, XCR1));
        dev_dbg(mcbsp->dev, "SRGR2: 0x%04x\n", MCBSP_READ(mcbsp, SRGR2));
        dev_dbg(mcbsp->dev, "SRGR1: 0x%04x\n", MCBSP_READ(mcbsp, SRGR1));
        dev_dbg(mcbsp->dev, "PCR0:  0x%04x\n", MCBSP_READ(mcbsp, PCR0));
        dev_dbg(mcbsp->dev, "***********************\n");
}

static int omap2_mcbsp_set_clks_src(struct omap_mcbsp *mcbsp, u8 fck_src_id)
{
        struct clk *fck_src;
        const char *src;
        int r;

        if (fck_src_id == MCBSP_CLKS_PAD_SRC)
                src = "pad_fck";
        else if (fck_src_id == MCBSP_CLKS_PRCM_SRC)
                src = "prcm_fck";
        else
                return -EINVAL;

        fck_src = clk_get(mcbsp->dev, src);
        if (IS_ERR(fck_src)) {
                dev_err(mcbsp->dev, "CLKS: could not clk_get() %s\n", src);
                return -EINVAL;
        }

        pm_runtime_put_sync(mcbsp->dev);

        r = clk_set_parent(mcbsp->fclk, fck_src);
        if (r) {
                dev_err(mcbsp->dev, "CLKS: could not clk_set_parent() to %s\n",
                        src);
                clk_put(fck_src);
                return r;
        }

        pm_runtime_get_sync(mcbsp->dev);

        clk_put(fck_src);

        return 0;
}

static irqreturn_t omap_mcbsp_irq_handler(int irq, void *data)
{
        struct omap_mcbsp *mcbsp = data;
        u16 irqst;

        irqst = MCBSP_READ(mcbsp, IRQST);
        dev_dbg(mcbsp->dev, "IRQ callback : 0x%x\n", irqst);

        if (irqst & RSYNCERREN)
                dev_err(mcbsp->dev, "RX Frame Sync Error!\n");
        if (irqst & RFSREN)
                dev_dbg(mcbsp->dev, "RX Frame Sync\n");
        if (irqst & REOFEN)
                dev_dbg(mcbsp->dev, "RX End Of Frame\n");
        if (irqst & RRDYEN)
                dev_dbg(mcbsp->dev, "RX Buffer Threshold Reached\n");
        if (irqst & RUNDFLEN)
                dev_err(mcbsp->dev, "RX Buffer Underflow!\n");
        if (irqst & ROVFLEN)
                dev_err(mcbsp->dev, "RX Buffer Overflow!\n");

        if (irqst & XSYNCERREN)
                dev_err(mcbsp->dev, "TX Frame Sync Error!\n");
        if (irqst & XFSXEN)
                dev_dbg(mcbsp->dev, "TX Frame Sync\n");
        if (irqst & XEOFEN)
                dev_dbg(mcbsp->dev, "TX End Of Frame\n");
        if (irqst & XRDYEN)
                dev_dbg(mcbsp->dev, "TX Buffer threshold Reached\n");
        if (irqst & XUNDFLEN)
                dev_err(mcbsp->dev, "TX Buffer Underflow!\n");
        if (irqst & XOVFLEN)
                dev_err(mcbsp->dev, "TX Buffer Overflow!\n");
        if (irqst & XEMPTYEOFEN)
                dev_dbg(mcbsp->dev, "TX Buffer empty at end of frame\n");

        MCBSP_WRITE(mcbsp, IRQST, irqst);

        return IRQ_HANDLED;
}

static irqreturn_t omap_mcbsp_tx_irq_handler(int irq, void *data)
{
        struct omap_mcbsp *mcbsp = data;
        u16 irqst_spcr2;

        irqst_spcr2 = MCBSP_READ(mcbsp, SPCR2);
        dev_dbg(mcbsp->dev, "TX IRQ callback : 0x%x\n", irqst_spcr2);

        if (irqst_spcr2 & XSYNC_ERR) {
                dev_err(mcbsp->dev, "TX Frame Sync Error! : 0x%x\n",
                        irqst_spcr2);
                /* Writing zero to XSYNC_ERR clears the IRQ */
                MCBSP_WRITE(mcbsp, SPCR2, MCBSP_READ_CACHE(mcbsp, SPCR2));
        }

        return IRQ_HANDLED;
}

static irqreturn_t omap_mcbsp_rx_irq_handler(int irq, void *data)
{
        struct omap_mcbsp *mcbsp = data;
        u16 irqst_spcr1;

        irqst_spcr1 = MCBSP_READ(mcbsp, SPCR1);
        dev_dbg(mcbsp->dev, "RX IRQ callback : 0x%x\n", irqst_spcr1);

        if (irqst_spcr1 & RSYNC_ERR) {
                dev_err(mcbsp->dev, "RX Frame Sync Error! : 0x%x\n",
                        irqst_spcr1);
                /* Writing zero to RSYNC_ERR clears the IRQ */
                MCBSP_WRITE(mcbsp, SPCR1, MCBSP_READ_CACHE(mcbsp, SPCR1));
        }

        return IRQ_HANDLED;
}

/*
 * omap_mcbsp_config simply write a config to the
 * appropriate McBSP.
 * You either call this function or set the McBSP registers
 * by yourself before calling omap_mcbsp_start().
 */
static void omap_mcbsp_config(struct omap_mcbsp *mcbsp,
                              const struct omap_mcbsp_reg_cfg *config)
{
        dev_dbg(mcbsp->dev, "Configuring McBSP%d  phys_base: 0x%08lx\n",
                mcbsp->id, mcbsp->phys_base);

        /* We write the given config */
        MCBSP_WRITE(mcbsp, SPCR2, config->spcr2);
        MCBSP_WRITE(mcbsp, SPCR1, config->spcr1);
        MCBSP_WRITE(mcbsp, RCR2, config->rcr2);
        MCBSP_WRITE(mcbsp, RCR1, config->rcr1);
        MCBSP_WRITE(mcbsp, XCR2, config->xcr2);
        MCBSP_WRITE(mcbsp, XCR1, config->xcr1);
        MCBSP_WRITE(mcbsp, SRGR2, config->srgr2);
        MCBSP_WRITE(mcbsp, SRGR1, config->srgr1);
        MCBSP_WRITE(mcbsp, MCR2, config->mcr2);
        MCBSP_WRITE(mcbsp, MCR1, config->mcr1);
        MCBSP_WRITE(mcbsp, PCR0, config->pcr0);
        if (mcbsp->pdata->has_ccr) {
                MCBSP_WRITE(mcbsp, XCCR, config->xccr);
                MCBSP_WRITE(mcbsp, RCCR, config->rccr);
        }
        /* Enable wakeup behavior */
        if (mcbsp->pdata->has_wakeup)
                MCBSP_WRITE(mcbsp, WAKEUPEN, XRDYEN | RRDYEN);

        /* Enable TX/RX sync error interrupts by default */
        if (mcbsp->irq)
                MCBSP_WRITE(mcbsp, IRQEN, RSYNCERREN | XSYNCERREN |
                            RUNDFLEN | ROVFLEN | XUNDFLEN | XOVFLEN);
}

/**
 * omap_mcbsp_dma_reg_params - returns the address of mcbsp data register
 * @mcbsp: omap_mcbsp struct for the McBSP instance
 * @stream: Stream direction (playback/capture)
 *
 * Returns the address of mcbsp data transmit register or data receive register
 * to be used by DMA for transferring/receiving data
 */
static int omap_mcbsp_dma_reg_params(struct omap_mcbsp *mcbsp,
                                     unsigned int stream)
{
        int data_reg;

        if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
                if (mcbsp->pdata->reg_size == 2)
                        data_reg = OMAP_MCBSP_REG_DXR1;
                else
                        data_reg = OMAP_MCBSP_REG_DXR;
        } else {
                if (mcbsp->pdata->reg_size == 2)
                        data_reg = OMAP_MCBSP_REG_DRR1;
                else
                        data_reg = OMAP_MCBSP_REG_DRR;
        }

        return mcbsp->phys_dma_base + data_reg * mcbsp->pdata->reg_step;
}

/*
 * omap_mcbsp_set_rx_threshold configures the transmit threshold in words.
 * The threshold parameter is 1 based, and it is converted (threshold - 1)
 * for the THRSH2 register.
 */
static void omap_mcbsp_set_tx_threshold(struct omap_mcbsp *mcbsp, u16 threshold)
{
        if (threshold && threshold <= mcbsp->max_tx_thres)
                MCBSP_WRITE(mcbsp, THRSH2, threshold - 1);
}

/*
 * omap_mcbsp_set_rx_threshold configures the receive threshold in words.
 * The threshold parameter is 1 based, and it is converted (threshold - 1)
 * for the THRSH1 register.
 */
static void omap_mcbsp_set_rx_threshold(struct omap_mcbsp *mcbsp, u16 threshold)
{
        if (threshold && threshold <= mcbsp->max_rx_thres)
                MCBSP_WRITE(mcbsp, THRSH1, threshold - 1);
}

/*
 * omap_mcbsp_get_tx_delay returns the number of used slots in the McBSP FIFO
 */
static u16 omap_mcbsp_get_tx_delay(struct omap_mcbsp *mcbsp)
{
        u16 buffstat;

        /* Returns the number of free locations in the buffer */
        buffstat = MCBSP_READ(mcbsp, XBUFFSTAT);

        /* Number of slots are different in McBSP ports */
        return mcbsp->pdata->buffer_size - buffstat;
}

/*
 * omap_mcbsp_get_rx_delay returns the number of free slots in the McBSP FIFO
 * to reach the threshold value (when the DMA will be triggered to read it)
 */
static u16 omap_mcbsp_get_rx_delay(struct omap_mcbsp *mcbsp)
{
        u16 buffstat, threshold;

        /* Returns the number of used locations in the buffer */
        buffstat = MCBSP_READ(mcbsp, RBUFFSTAT);
        /* RX threshold */
        threshold = MCBSP_READ(mcbsp, THRSH1);

        /* Return the number of location till we reach the threshold limit */
        if (threshold <= buffstat)
                return 0;
        else
                return threshold - buffstat;
}

static int omap_mcbsp_request(struct omap_mcbsp *mcbsp)
{
        void *reg_cache;
        int err;

        reg_cache = kzalloc(mcbsp->reg_cache_size, GFP_KERNEL);
        if (!reg_cache)
                return -ENOMEM;

        spin_lock(&mcbsp->lock);
        if (!mcbsp->free) {
                dev_err(mcbsp->dev, "McBSP%d is currently in use\n", mcbsp->id);
                err = -EBUSY;
                goto err_kfree;
        }

        mcbsp->free = false;
        mcbsp->reg_cache = reg_cache;
        spin_unlock(&mcbsp->lock);

        if(mcbsp->pdata->ops && mcbsp->pdata->ops->request)
                mcbsp->pdata->ops->request(mcbsp->id - 1);

        /*
         * Make sure that transmitter, receiver and sample-rate generator are
         * not running before activating IRQs.
         */
        MCBSP_WRITE(mcbsp, SPCR1, 0);
        MCBSP_WRITE(mcbsp, SPCR2, 0);

        if (mcbsp->irq) {
                err = request_irq(mcbsp->irq, omap_mcbsp_irq_handler, 0,
                                  "McBSP", (void *)mcbsp);
                if (err != 0) {
                        dev_err(mcbsp->dev, "Unable to request IRQ\n");
                        goto err_clk_disable;
                }
        } else {
                err = request_irq(mcbsp->tx_irq, omap_mcbsp_tx_irq_handler, 0,
                                  "McBSP TX", (void *)mcbsp);
                if (err != 0) {
                        dev_err(mcbsp->dev, "Unable to request TX IRQ\n");
                        goto err_clk_disable;
                }

                err = request_irq(mcbsp->rx_irq, omap_mcbsp_rx_irq_handler, 0,
                                  "McBSP RX", (void *)mcbsp);
                if (err != 0) {
                        dev_err(mcbsp->dev, "Unable to request RX IRQ\n");
                        goto err_free_irq;
                }
        }

        return 0;
err_free_irq:
        free_irq(mcbsp->tx_irq, (void *)mcbsp);
err_clk_disable:
        if(mcbsp->pdata->ops && mcbsp->pdata->ops->free)
                mcbsp->pdata->ops->free(mcbsp->id - 1);

        /* Disable wakeup behavior */
        if (mcbsp->pdata->has_wakeup)
                MCBSP_WRITE(mcbsp, WAKEUPEN, 0);

        spin_lock(&mcbsp->lock);
        mcbsp->free = true;
        mcbsp->reg_cache = NULL;
err_kfree:
        spin_unlock(&mcbsp->lock);
        kfree(reg_cache);

        return err;
}

static void omap_mcbsp_free(struct omap_mcbsp *mcbsp)
{
        void *reg_cache;

        if(mcbsp->pdata->ops && mcbsp->pdata->ops->free)
                mcbsp->pdata->ops->free(mcbsp->id - 1);

        /* Disable wakeup behavior */
        if (mcbsp->pdata->has_wakeup)
                MCBSP_WRITE(mcbsp, WAKEUPEN, 0);

        /* Disable interrupt requests */
        if (mcbsp->irq)
                MCBSP_WRITE(mcbsp, IRQEN, 0);

        if (mcbsp->irq) {
                free_irq(mcbsp->irq, (void *)mcbsp);
        } else {
                free_irq(mcbsp->rx_irq, (void *)mcbsp);
                free_irq(mcbsp->tx_irq, (void *)mcbsp);
        }

        reg_cache = mcbsp->reg_cache;

        /*
         * Select CLKS source from internal source unconditionally before
         * marking the McBSP port as free.
         * If the external clock source via MCBSP_CLKS pin has been selected the
         * system will refuse to enter idle if the CLKS pin source is not reset
         * back to internal source.
         */
        if (!mcbsp_omap1())
                omap2_mcbsp_set_clks_src(mcbsp, MCBSP_CLKS_PRCM_SRC);

        spin_lock(&mcbsp->lock);
        if (mcbsp->free)
                dev_err(mcbsp->dev, "McBSP%d was not reserved\n", mcbsp->id);
        else
                mcbsp->free = true;
        mcbsp->reg_cache = NULL;
        spin_unlock(&mcbsp->lock);

        kfree(reg_cache);
}

/*
 * Here we start the McBSP, by enabling transmitter, receiver or both.
 * If no transmitter or receiver is active prior calling, then sample-rate
 * generator and frame sync are started.
 */
static void omap_mcbsp_start(struct omap_mcbsp *mcbsp, int stream)
{
        int tx = (stream == SNDRV_PCM_STREAM_PLAYBACK);
        int rx = !tx;
        int enable_srg = 0;
        u16 w;

        if (mcbsp->st_data)
                omap_mcbsp_st_start(mcbsp);

        /* Only enable SRG, if McBSP is master */
        w = MCBSP_READ_CACHE(mcbsp, PCR0);
        if (w & (FSXM | FSRM | CLKXM | CLKRM))
                enable_srg = !((MCBSP_READ_CACHE(mcbsp, SPCR2) |
                                MCBSP_READ_CACHE(mcbsp, SPCR1)) & 1);

        if (enable_srg) {
                /* Start the sample generator */
                w = MCBSP_READ_CACHE(mcbsp, SPCR2);
                MCBSP_WRITE(mcbsp, SPCR2, w | (1 << 6));
        }

        /* Enable transmitter and receiver */
        tx &= 1;
        w = MCBSP_READ_CACHE(mcbsp, SPCR2);
        MCBSP_WRITE(mcbsp, SPCR2, w | tx);

        rx &= 1;
        w = MCBSP_READ_CACHE(mcbsp, SPCR1);
        MCBSP_WRITE(mcbsp, SPCR1, w | rx);

        /*
         * Worst case: CLKSRG*2 = 8000khz: (1/8000) * 2 * 2 usec
         * REVISIT: 100us may give enough time for two CLKSRG, however
         * due to some unknown PM related, clock gating etc. reason it
         * is now at 500us.
         */
        udelay(500);

        if (enable_srg) {
                /* Start frame sync */
                w = MCBSP_READ_CACHE(mcbsp, SPCR2);
                MCBSP_WRITE(mcbsp, SPCR2, w | (1 << 7));
        }

        if (mcbsp->pdata->has_ccr) {
                /* Release the transmitter and receiver */
                w = MCBSP_READ_CACHE(mcbsp, XCCR);
                w &= ~(tx ? XDISABLE : 0);
                MCBSP_WRITE(mcbsp, XCCR, w);
                w = MCBSP_READ_CACHE(mcbsp, RCCR);
                w &= ~(rx ? RDISABLE : 0);
                MCBSP_WRITE(mcbsp, RCCR, w);
        }

        /* Dump McBSP Regs */
        omap_mcbsp_dump_reg(mcbsp);
}

static void omap_mcbsp_stop(struct omap_mcbsp *mcbsp, int stream)
{
        int tx = (stream == SNDRV_PCM_STREAM_PLAYBACK);
        int rx = !tx;
        int idle;
        u16 w;

        /* Reset transmitter */
        tx &= 1;
        if (mcbsp->pdata->has_ccr) {
                w = MCBSP_READ_CACHE(mcbsp, XCCR);
                w |= (tx ? XDISABLE : 0);
                MCBSP_WRITE(mcbsp, XCCR, w);
        }
        w = MCBSP_READ_CACHE(mcbsp, SPCR2);
        MCBSP_WRITE(mcbsp, SPCR2, w & ~tx);

        /* Reset receiver */
        rx &= 1;
        if (mcbsp->pdata->has_ccr) {
                w = MCBSP_READ_CACHE(mcbsp, RCCR);
                w |= (rx ? RDISABLE : 0);
                MCBSP_WRITE(mcbsp, RCCR, w);
        }
        w = MCBSP_READ_CACHE(mcbsp, SPCR1);
        MCBSP_WRITE(mcbsp, SPCR1, w & ~rx);

        idle = !((MCBSP_READ_CACHE(mcbsp, SPCR2) |
                        MCBSP_READ_CACHE(mcbsp, SPCR1)) & 1);

        if (idle) {
                /* Reset the sample rate generator */
                w = MCBSP_READ_CACHE(mcbsp, SPCR2);
                MCBSP_WRITE(mcbsp, SPCR2, w & ~(1 << 6));
        }

        if (mcbsp->st_data)
                omap_mcbsp_st_stop(mcbsp);
}

#define max_thres(m)                    (mcbsp->pdata->buffer_size)
#define valid_threshold(m, val)         ((val) <= max_thres(m))
#define THRESHOLD_PROP_BUILDER(prop)                                    \
static ssize_t prop##_show(struct device *dev,                          \
                        struct device_attribute *attr, char *buf)       \
{                                                                       \
        struct omap_mcbsp *mcbsp = dev_get_drvdata(dev);                \
                                                                        \
        return sprintf(buf, "%u\n", mcbsp->prop);                       \
}                                                                       \
                                                                        \
static ssize_t prop##_store(struct device *dev,                         \
                                struct device_attribute *attr,          \
                                const char *buf, size_t size)           \
{                                                                       \
        struct omap_mcbsp *mcbsp = dev_get_drvdata(dev);                \
        unsigned long val;                                              \
        int status;                                                     \
                                                                        \
        status = kstrtoul(buf, 0, &val);                                \
        if (status)                                                     \
                return status;                                          \
                                                                        \
        if (!valid_threshold(mcbsp, val))                               \
                return -EDOM;                                           \
                                                                        \
        mcbsp->prop = val;                                              \
        return size;                                                    \
}                                                                       \
                                                                        \
static DEVICE_ATTR(prop, 0644, prop##_show, prop##_store)

THRESHOLD_PROP_BUILDER(max_tx_thres);
THRESHOLD_PROP_BUILDER(max_rx_thres);

static const char * const dma_op_modes[] = {
        "element", "threshold",
};

static ssize_t dma_op_mode_show(struct device *dev,
                                struct device_attribute *attr, char *buf)
{
        struct omap_mcbsp *mcbsp = dev_get_drvdata(dev);
        int dma_op_mode, i = 0;
        ssize_t len = 0;
        const char * const *s;

        dma_op_mode = mcbsp->dma_op_mode;

        for (s = &dma_op_modes[i]; i < ARRAY_SIZE(dma_op_modes); s++, i++) {
                if (dma_op_mode == i)
                        len += sprintf(buf + len, "[%s] ", *s);
                else
                        len += sprintf(buf + len, "%s ", *s);
        }
        len += sprintf(buf + len, "\n");

        return len;
}

static ssize_t dma_op_mode_store(struct device *dev,
                                 struct device_attribute *attr, const char *buf,
                                 size_t size)
{
        struct omap_mcbsp *mcbsp = dev_get_drvdata(dev);
        int i;

        i = sysfs_match_string(dma_op_modes, buf);
        if (i < 0)
                return i;

        spin_lock_irq(&mcbsp->lock);
        if (!mcbsp->free) {
                size = -EBUSY;
                goto unlock;
        }
        mcbsp->dma_op_mode = i;

unlock:
        spin_unlock_irq(&mcbsp->lock);

        return size;
}

static DEVICE_ATTR_RW(dma_op_mode);

static const struct attribute *additional_attrs[] = {
        &dev_attr_max_tx_thres.attr,
        &dev_attr_max_rx_thres.attr,
        &dev_attr_dma_op_mode.attr,
        NULL,
};

static const struct attribute_group additional_attr_group = {
        .attrs = (struct attribute **)additional_attrs,
};

/*
 * McBSP1 and McBSP3 are directly mapped on 1610 and 1510.
 * 730 has only 2 McBSP, and both of them are MPU peripherals.
 */
static int omap_mcbsp_init(struct platform_device *pdev)
{
        struct omap_mcbsp *mcbsp = platform_get_drvdata(pdev);
        struct resource *res;
        int ret = 0;

        spin_lock_init(&mcbsp->lock);
        mcbsp->free = true;

        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mpu");
        if (!res)
                res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

        mcbsp->io_base = devm_ioremap_resource(&pdev->dev, res);
        if (IS_ERR(mcbsp->io_base))
                return PTR_ERR(mcbsp->io_base);

        mcbsp->phys_base = res->start;
        mcbsp->reg_cache_size = resource_size(res);

        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dma");
        if (!res)
                mcbsp->phys_dma_base = mcbsp->phys_base;
        else
                mcbsp->phys_dma_base = res->start;

        /*
         * OMAP1, 2 uses two interrupt lines: TX, RX
         * OMAP2430, OMAP3 SoC have combined IRQ line as well.
         * OMAP4 and newer SoC only have the combined IRQ line.
         * Use the combined IRQ if available since it gives better debugging
         * possibilities.
         */
        mcbsp->irq = platform_get_irq_byname(pdev, "common");
        if (mcbsp->irq == -ENXIO) {
                mcbsp->tx_irq = platform_get_irq_byname(pdev, "tx");

                if (mcbsp->tx_irq == -ENXIO) {
                        mcbsp->irq = platform_get_irq(pdev, 0);
                        mcbsp->tx_irq = 0;
                } else {
                        mcbsp->rx_irq = platform_get_irq_byname(pdev, "rx");
                        mcbsp->irq = 0;
                }
        }

        if (!pdev->dev.of_node) {
                res = platform_get_resource_byname(pdev, IORESOURCE_DMA, "tx");
                if (!res) {
                        dev_err(&pdev->dev, "invalid tx DMA channel\n");
                        return -ENODEV;
                }
                mcbsp->dma_req[0] = res->start;
                mcbsp->dma_data[0].filter_data = &mcbsp->dma_req[0];

                res = platform_get_resource_byname(pdev, IORESOURCE_DMA, "rx");
                if (!res) {
                        dev_err(&pdev->dev, "invalid rx DMA channel\n");
                        return -ENODEV;
                }
                mcbsp->dma_req[1] = res->start;
                mcbsp->dma_data[1].filter_data = &mcbsp->dma_req[1];
        } else {
                mcbsp->dma_data[0].filter_data = "tx";
                mcbsp->dma_data[1].filter_data = "rx";
        }

        mcbsp->dma_data[0].addr = omap_mcbsp_dma_reg_params(mcbsp,
                                                SNDRV_PCM_STREAM_PLAYBACK);
        mcbsp->dma_data[1].addr = omap_mcbsp_dma_reg_params(mcbsp,
                                                SNDRV_PCM_STREAM_CAPTURE);

        mcbsp->fclk = clk_get(&pdev->dev, "fck");
        if (IS_ERR(mcbsp->fclk)) {
                ret = PTR_ERR(mcbsp->fclk);
                dev_err(mcbsp->dev, "unable to get fck: %d\n", ret);
                return ret;
        }

        mcbsp->dma_op_mode = MCBSP_DMA_MODE_ELEMENT;
        if (mcbsp->pdata->buffer_size) {
                /*
                 * Initially configure the maximum thresholds to a safe value.
                 * The McBSP FIFO usage with these values should not go under
                 * 16 locations.
                 * If the whole FIFO without safety buffer is used, than there
                 * is a possibility that the DMA will be not able to push the
                 * new data on time, causing channel shifts in runtime.
                 */
                mcbsp->max_tx_thres = max_thres(mcbsp) - 0x10;
                mcbsp->max_rx_thres = max_thres(mcbsp) - 0x10;

                ret = sysfs_create_group(&mcbsp->dev->kobj,
                                         &additional_attr_group);
                if (ret) {
                        dev_err(mcbsp->dev,
                                "Unable to create additional controls\n");
                        goto err_thres;
                }
        }

        ret = omap_mcbsp_st_init(pdev);
        if (ret)
                goto err_st;

        return 0;

err_st:
        if (mcbsp->pdata->buffer_size)
                sysfs_remove_group(&mcbsp->dev->kobj, &additional_attr_group);
err_thres:
        clk_put(mcbsp->fclk);
        return ret;
}

/*
 * Stream DMA parameters. DMA request line and port address are set runtime
 * since they are different between OMAP1 and later OMAPs
 */
static void omap_mcbsp_set_threshold(struct snd_pcm_substream *substream,
                unsigned int packet_size)
{
        struct snd_soc_pcm_runtime *rtd = substream->private_data;
        struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
        struct omap_mcbsp *mcbsp = snd_soc_dai_get_drvdata(cpu_dai);
        int words;

        /* No need to proceed further if McBSP does not have FIFO */
        if (mcbsp->pdata->buffer_size == 0)
                return;

        /*
         * Configure McBSP threshold based on either:
         * packet_size, when the sDMA is in packet mode, or based on the
         * period size in THRESHOLD mode, otherwise use McBSP threshold = 1
         * for mono streams.
         */
        if (packet_size)
                words = packet_size;
        else
                words = 1;

        /* Configure McBSP internal buffer usage */
        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                omap_mcbsp_set_tx_threshold(mcbsp, words);
        else
                omap_mcbsp_set_rx_threshold(mcbsp, words);
}

static int omap_mcbsp_hwrule_min_buffersize(struct snd_pcm_hw_params *params,
                                    struct snd_pcm_hw_rule *rule)
{
        struct snd_interval *buffer_size = hw_param_interval(params,
                                        SNDRV_PCM_HW_PARAM_BUFFER_SIZE);
        struct snd_interval *channels = hw_param_interval(params,
                                        SNDRV_PCM_HW_PARAM_CHANNELS);
        struct omap_mcbsp *mcbsp = rule->private;
        struct snd_interval frames;
        int size;

        snd_interval_any(&frames);
        size = mcbsp->pdata->buffer_size;

        frames.min = size / channels->min;
        frames.integer = 1;
        return snd_interval_refine(buffer_size, &frames);
}

static int omap_mcbsp_dai_startup(struct snd_pcm_substream *substream,
                                  struct snd_soc_dai *cpu_dai)
{
        struct omap_mcbsp *mcbsp = snd_soc_dai_get_drvdata(cpu_dai);
        int err = 0;

        if (!cpu_dai->active)
                err = omap_mcbsp_request(mcbsp);

        /*
         * OMAP3 McBSP FIFO is word structured.
         * McBSP2 has 1024 + 256 = 1280 word long buffer,
         * McBSP1,3,4,5 has 128 word long buffer
         * This means that the size of the FIFO depends on the sample format.
         * For example on McBSP3:
         * 16bit samples: size is 128 * 2 = 256 bytes
         * 32bit samples: size is 128 * 4 = 512 bytes
         * It is simpler to place constraint for buffer and period based on
         * channels.
         * McBSP3 as example again (16 or 32 bit samples):
         * 1 channel (mono): size is 128 frames (128 words)
         * 2 channels (stereo): size is 128 / 2 = 64 frames (2 * 64 words)
         * 4 channels: size is 128 / 4 = 32 frames (4 * 32 words)
         */
        if (mcbsp->pdata->buffer_size) {
                /*
                * Rule for the buffer size. We should not allow
                * smaller buffer than the FIFO size to avoid underruns.
                * This applies only for the playback stream.
                */
                if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                        snd_pcm_hw_rule_add(substream->runtime, 0,
                                            SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
                                            omap_mcbsp_hwrule_min_buffersize,
                                            mcbsp,
                                            SNDRV_PCM_HW_PARAM_CHANNELS, -1);

                /* Make sure, that the period size is always even */
                snd_pcm_hw_constraint_step(substream->runtime, 0,
                                           SNDRV_PCM_HW_PARAM_PERIOD_SIZE, 2);
        }

        return err;
}

static void omap_mcbsp_dai_shutdown(struct snd_pcm_substream *substream,
                                    struct snd_soc_dai *cpu_dai)
{
        struct omap_mcbsp *mcbsp = snd_soc_dai_get_drvdata(cpu_dai);
        int tx = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK);
        int stream1 = tx ? SNDRV_PCM_STREAM_PLAYBACK : SNDRV_PCM_STREAM_CAPTURE;
        int stream2 = tx ? SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK;

        if (mcbsp->latency[stream2])
                pm_qos_update_request(&mcbsp->pm_qos_req,
                                      mcbsp->latency[stream2]);
        else if (mcbsp->latency[stream1])
                pm_qos_remove_request(&mcbsp->pm_qos_req);

        mcbsp->latency[stream1] = 0;

        if (!cpu_dai->active) {
                omap_mcbsp_free(mcbsp);
                mcbsp->configured = 0;
        }
}

static int omap_mcbsp_dai_prepare(struct snd_pcm_substream *substream,
                                  struct snd_soc_dai *cpu_dai)
{
        struct omap_mcbsp *mcbsp = snd_soc_dai_get_drvdata(cpu_dai);
        struct pm_qos_request *pm_qos_req = &mcbsp->pm_qos_req;
        int tx = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK);
        int stream1 = tx ? SNDRV_PCM_STREAM_PLAYBACK : SNDRV_PCM_STREAM_CAPTURE;
        int stream2 = tx ? SNDRV_PCM_STREAM_CAPTURE : SNDRV_PCM_STREAM_PLAYBACK;
        int latency = mcbsp->latency[stream2];

        /* Prevent omap hardware from hitting off between FIFO fills */
        if (!latency || mcbsp->latency[stream1] < latency)
                latency = mcbsp->latency[stream1];

        if (pm_qos_request_active(pm_qos_req))
                pm_qos_update_request(pm_qos_req, latency);
        else if (latency)
                pm_qos_add_request(pm_qos_req, PM_QOS_CPU_DMA_LATENCY, latency);

        return 0;
}

static int omap_mcbsp_dai_trigger(struct snd_pcm_substream *substream, int cmd,
                                  struct snd_soc_dai *cpu_dai)
{
        struct omap_mcbsp *mcbsp = snd_soc_dai_get_drvdata(cpu_dai);

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_RESUME:
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
                mcbsp->active++;
                omap_mcbsp_start(mcbsp, substream->stream);
                break;

        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_SUSPEND:
        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
                omap_mcbsp_stop(mcbsp, substream->stream);
                mcbsp->active--;
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static snd_pcm_sframes_t omap_mcbsp_dai_delay(
                        struct snd_pcm_substream *substream,
                        struct snd_soc_dai *dai)
{
        struct snd_soc_pcm_runtime *rtd = substream->private_data;
        struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
        struct omap_mcbsp *mcbsp = snd_soc_dai_get_drvdata(cpu_dai);
        u16 fifo_use;
        snd_pcm_sframes_t delay;

        /* No need to proceed further if McBSP does not have FIFO */
        if (mcbsp->pdata->buffer_size == 0)
                return 0;

        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                fifo_use = omap_mcbsp_get_tx_delay(mcbsp);
        else
                fifo_use = omap_mcbsp_get_rx_delay(mcbsp);

        /*
         * Divide the used locations with the channel count to get the
         * FIFO usage in samples (don't care about partial samples in the
         * buffer).
         */
        delay = fifo_use / substream->runtime->channels;

        return delay;
}

static int omap_mcbsp_dai_hw_params(struct snd_pcm_substream *substream,
                                    struct snd_pcm_hw_params *params,
                                    struct snd_soc_dai *cpu_dai)
{
        struct omap_mcbsp *mcbsp = snd_soc_dai_get_drvdata(cpu_dai);
        struct omap_mcbsp_reg_cfg *regs = &mcbsp->cfg_regs;
        struct snd_dmaengine_dai_dma_data *dma_data;
        int wlen, channels, wpf;
        int pkt_size = 0;
        unsigned int format, div, framesize, master;
        unsigned int buffer_size = mcbsp->pdata->buffer_size;

        dma_data = snd_soc_dai_get_dma_data(cpu_dai, substream);
        channels = params_channels(params);

        switch (params_format(params)) {
        case SNDRV_PCM_FORMAT_S16_LE:
                wlen = 16;
                break;
        case SNDRV_PCM_FORMAT_S32_LE:
                wlen = 32;
                break;
        default:
                return -EINVAL;
        }
        if (buffer_size) {
                int latency;

                if (mcbsp->dma_op_mode == MCBSP_DMA_MODE_THRESHOLD) {
                        int period_words, max_thrsh;
                        int divider = 0;

                        period_words = params_period_bytes(params) / (wlen / 8);
                        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                                max_thrsh = mcbsp->max_tx_thres;
                        else
                                max_thrsh = mcbsp->max_rx_thres;
                        /*
                         * Use sDMA packet mode if McBSP is in threshold mode:
                         * If period words less than the FIFO size the packet
                         * size is set to the number of period words, otherwise
                         * Look for the biggest threshold value which divides
                         * the period size evenly.
                         */
                        divider = period_words / max_thrsh;
                        if (period_words % max_thrsh)
                                divider++;
                        while (period_words % divider &&
                                divider < period_words)
                                divider++;
                        if (divider == period_words)
                                return -EINVAL;

                        pkt_size = period_words / divider;
                } else if (channels > 1) {
                        /* Use packet mode for non mono streams */
                        pkt_size = channels;
                }

                latency = (buffer_size - pkt_size) / channels;
                latency = latency * USEC_PER_SEC /
                          (params->rate_num / params->rate_den);
                mcbsp->latency[substream->stream] = latency;

                omap_mcbsp_set_threshold(substream, pkt_size);
        }

        dma_data->maxburst = pkt_size;

        if (mcbsp->configured) {
                /* McBSP already configured by another stream */
                return 0;
        }

        regs->rcr2      &= ~(RPHASE | RFRLEN2(0x7f) | RWDLEN2(7));
        regs->xcr2      &= ~(RPHASE | XFRLEN2(0x7f) | XWDLEN2(7));
        regs->rcr1      &= ~(RFRLEN1(0x7f) | RWDLEN1(7));
        regs->xcr1      &= ~(XFRLEN1(0x7f) | XWDLEN1(7));
        format = mcbsp->fmt & SND_SOC_DAIFMT_FORMAT_MASK;
        wpf = channels;
        if (channels == 2 && (format == SND_SOC_DAIFMT_I2S ||
                              format == SND_SOC_DAIFMT_LEFT_J)) {
                /* Use dual-phase frames */
                regs->rcr2      |= RPHASE;
                regs->xcr2      |= XPHASE;
                /* Set 1 word per (McBSP) frame for phase1 and phase2 */
                wpf--;
                regs->rcr2      |= RFRLEN2(wpf - 1);
                regs->xcr2      |= XFRLEN2(wpf - 1);
        }

        regs->rcr1      |= RFRLEN1(wpf - 1);
        regs->xcr1      |= XFRLEN1(wpf - 1);

        switch (params_format(params)) {
        case SNDRV_PCM_FORMAT_S16_LE:
                /* Set word lengths */
                regs->rcr2      |= RWDLEN2(OMAP_MCBSP_WORD_16);
                regs->rcr1      |= RWDLEN1(OMAP_MCBSP_WORD_16);
                regs->xcr2      |= XWDLEN2(OMAP_MCBSP_WORD_16);
                regs->xcr1      |= XWDLEN1(OMAP_MCBSP_WORD_16);
                break;
        case SNDRV_PCM_FORMAT_S32_LE:
                /* Set word lengths */
                regs->rcr2      |= RWDLEN2(OMAP_MCBSP_WORD_32);
                regs->rcr1      |= RWDLEN1(OMAP_MCBSP_WORD_32);
                regs->xcr2      |= XWDLEN2(OMAP_MCBSP_WORD_32);
                regs->xcr1      |= XWDLEN1(OMAP_MCBSP_WORD_32);
                break;
        default:
                /* Unsupported PCM format */
                return -EINVAL;
        }

        /* In McBSP master modes, FRAME (i.e. sample rate) is generated
         * by _counting_ BCLKs. Calculate frame size in BCLKs */
        master = mcbsp->fmt & SND_SOC_DAIFMT_MASTER_MASK;
        if (master ==   SND_SOC_DAIFMT_CBS_CFS) {
                div = mcbsp->clk_div ? mcbsp->clk_div : 1;
                framesize = (mcbsp->in_freq / div) / params_rate(params);

                if (framesize < wlen * channels) {
                        printk(KERN_ERR "%s: not enough bandwidth for desired rate and "
                                        "channels\n", __func__);
                        return -EINVAL;
                }
        } else
                framesize = wlen * channels;

        /* Set FS period and length in terms of bit clock periods */
        regs->srgr2     &= ~FPER(0xfff);
        regs->srgr1     &= ~FWID(0xff);
        switch (format) {
        case SND_SOC_DAIFMT_I2S:
        case SND_SOC_DAIFMT_LEFT_J:
                regs->srgr2     |= FPER(framesize - 1);
                regs->srgr1     |= FWID((framesize >> 1) - 1);
                break;
        case SND_SOC_DAIFMT_DSP_A:
        case SND_SOC_DAIFMT_DSP_B:
                regs->srgr2     |= FPER(framesize - 1);
                regs->srgr1     |= FWID(0);
                break;
        }

        omap_mcbsp_config(mcbsp, &mcbsp->cfg_regs);
        mcbsp->wlen = wlen;
        mcbsp->configured = 1;

        return 0;
}

/*
 * This must be called before _set_clkdiv and _set_sysclk since McBSP register
 * cache is initialized here
 */
static int omap_mcbsp_dai_set_dai_fmt(struct snd_soc_dai *cpu_dai,
                                      unsigned int fmt)
{
        struct omap_mcbsp *mcbsp = snd_soc_dai_get_drvdata(cpu_dai);
        struct omap_mcbsp_reg_cfg *regs = &mcbsp->cfg_regs;
        bool inv_fs = false;

        if (mcbsp->configured)
                return 0;

        mcbsp->fmt = fmt;
        memset(regs, 0, sizeof(*regs));
        /* Generic McBSP register settings */
        regs->spcr2     |= XINTM(3) | FREE;
        regs->spcr1     |= RINTM(3);
        /* RFIG and XFIG are not defined in 2430 and on OMAP3+ */
        if (!mcbsp->pdata->has_ccr) {
                regs->rcr2      |= RFIG;
                regs->xcr2      |= XFIG;
        }

        /* Configure XCCR/RCCR only for revisions which have ccr registers */
        if (mcbsp->pdata->has_ccr) {
                regs->xccr = DXENDLY(1) | XDMAEN | XDISABLE;
                regs->rccr = RFULL_CYCLE | RDMAEN | RDISABLE;
        }

        switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
        case SND_SOC_DAIFMT_I2S:
                /* 1-bit data delay */
                regs->rcr2      |= RDATDLY(1);
                regs->xcr2      |= XDATDLY(1);
                break;
        case SND_SOC_DAIFMT_LEFT_J:
                /* 0-bit data delay */
                regs->rcr2      |= RDATDLY(0);
                regs->xcr2      |= XDATDLY(0);
                regs->spcr1     |= RJUST(2);
                /* Invert FS polarity configuration */
                inv_fs = true;
                break;
        case SND_SOC_DAIFMT_DSP_A:
                /* 1-bit data delay */
                regs->rcr2      |= RDATDLY(1);
                regs->xcr2      |= XDATDLY(1);
                /* Invert FS polarity configuration */
                inv_fs = true;
                break;
        case SND_SOC_DAIFMT_DSP_B:
                /* 0-bit data delay */
                regs->rcr2      |= RDATDLY(0);
                regs->xcr2      |= XDATDLY(0);
                /* Invert FS polarity configuration */
                inv_fs = true;
                break;
        default:
                /* Unsupported data format */
                return -EINVAL;
        }

        switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
        case SND_SOC_DAIFMT_CBS_CFS:
                /* McBSP master. Set FS and bit clocks as outputs */
                regs->pcr0      |= FSXM | FSRM |
                                   CLKXM | CLKRM;
                /* Sample rate generator drives the FS */
                regs->srgr2     |= FSGM;
                break;
        case SND_SOC_DAIFMT_CBM_CFS:
                /* McBSP slave. FS clock as output */
                regs->srgr2     |= FSGM;
                regs->pcr0      |= FSXM | FSRM;
                break;
        case SND_SOC_DAIFMT_CBM_CFM:
                /* McBSP slave */
                break;
        default:
                /* Unsupported master/slave configuration */
                return -EINVAL;
        }

        /* Set bit clock (CLKX/CLKR) and FS polarities */
        switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
        case SND_SOC_DAIFMT_NB_NF:
                /*
                 * Normal BCLK + FS.
                 * FS active low. TX data driven on falling edge of bit clock
                 * and RX data sampled on rising edge of bit clock.
                 */
                regs->pcr0      |= FSXP | FSRP |
                                   CLKXP | CLKRP;
                break;
        case SND_SOC_DAIFMT_NB_IF:
                regs->pcr0      |= CLKXP | CLKRP;
                break;
        case SND_SOC_DAIFMT_IB_NF:
                regs->pcr0      |= FSXP | FSRP;
                break;
        case SND_SOC_DAIFMT_IB_IF:
                break;
        default:
                return -EINVAL;
        }
        if (inv_fs == true)
                regs->pcr0 ^= FSXP | FSRP;

        return 0;
}

static int omap_mcbsp_dai_set_clkdiv(struct snd_soc_dai *cpu_dai,
                                     int div_id, int div)
{
        struct omap_mcbsp *mcbsp = snd_soc_dai_get_drvdata(cpu_dai);
        struct omap_mcbsp_reg_cfg *regs = &mcbsp->cfg_regs;

        if (div_id != OMAP_MCBSP_CLKGDV)
                return -ENODEV;

        mcbsp->clk_div = div;
        regs->srgr1     &= ~CLKGDV(0xff);
        regs->srgr1     |= CLKGDV(div - 1);

        return 0;
}

static int omap_mcbsp_dai_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
                                         int clk_id, unsigned int freq,
                                         int dir)
{
        struct omap_mcbsp *mcbsp = snd_soc_dai_get_drvdata(cpu_dai);
        struct omap_mcbsp_reg_cfg *regs = &mcbsp->cfg_regs;
        int err = 0;

        if (mcbsp->active) {
                if (freq == mcbsp->in_freq)
                        return 0;
                else
                        return -EBUSY;
        }

        mcbsp->in_freq = freq;
        regs->srgr2 &= ~CLKSM;
        regs->pcr0 &= ~SCLKME;

        switch (clk_id) {
        case OMAP_MCBSP_SYSCLK_CLK:
                regs->srgr2     |= CLKSM;
                break;
        case OMAP_MCBSP_SYSCLK_CLKS_FCLK:
                if (mcbsp_omap1()) {
                        err = -EINVAL;
                        break;
                }
                err = omap2_mcbsp_set_clks_src(mcbsp,
                                               MCBSP_CLKS_PRCM_SRC);
                break;
        case OMAP_MCBSP_SYSCLK_CLKS_EXT:
                if (mcbsp_omap1()) {
                        err = 0;
                        break;
                }
                err = omap2_mcbsp_set_clks_src(mcbsp,
                                               MCBSP_CLKS_PAD_SRC);
                break;

        case OMAP_MCBSP_SYSCLK_CLKX_EXT:
                regs->srgr2     |= CLKSM;
                regs->pcr0      |= SCLKME;
                /*
                 * If McBSP is master but yet the CLKX/CLKR pin drives the SRG,
                 * disable output on those pins. This enables to inject the
                 * reference clock through CLKX/CLKR. For this to work
                 * set_dai_sysclk() _needs_ to be called after set_dai_fmt().
                 */
                regs->pcr0      &= ~CLKXM;
                break;
        case OMAP_MCBSP_SYSCLK_CLKR_EXT:
                regs->pcr0      |= SCLKME;
                /* Disable ouput on CLKR pin in master mode */
                regs->pcr0      &= ~CLKRM;
                break;
        default:
                err = -ENODEV;
        }

        return err;
}

static const struct snd_soc_dai_ops mcbsp_dai_ops = {
        .startup        = omap_mcbsp_dai_startup,
        .shutdown       = omap_mcbsp_dai_shutdown,
        .prepare        = omap_mcbsp_dai_prepare,
        .trigger        = omap_mcbsp_dai_trigger,
        .delay          = omap_mcbsp_dai_delay,
        .hw_params      = omap_mcbsp_dai_hw_params,
        .set_fmt        = omap_mcbsp_dai_set_dai_fmt,
        .set_clkdiv     = omap_mcbsp_dai_set_clkdiv,
        .set_sysclk     = omap_mcbsp_dai_set_dai_sysclk,
};

static int omap_mcbsp_probe(struct snd_soc_dai *dai)
{
        struct omap_mcbsp *mcbsp = snd_soc_dai_get_drvdata(dai);

        pm_runtime_enable(mcbsp->dev);

        snd_soc_dai_init_dma_data(dai,
                                  &mcbsp->dma_data[SNDRV_PCM_STREAM_PLAYBACK],
                                  &mcbsp->dma_data[SNDRV_PCM_STREAM_CAPTURE]);

        return 0;
}

static int omap_mcbsp_remove(struct snd_soc_dai *dai)
{
        struct omap_mcbsp *mcbsp = snd_soc_dai_get_drvdata(dai);

        pm_runtime_disable(mcbsp->dev);

        return 0;
}

static struct snd_soc_dai_driver omap_mcbsp_dai = {
        .probe = omap_mcbsp_probe,
        .remove = omap_mcbsp_remove,
        .playback = {
                .channels_min = 1,
                .channels_max = 16,
                .rates = OMAP_MCBSP_RATES,
                .formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S32_LE,
        },
        .capture = {
                .channels_min = 1,
                .channels_max = 16,
                .rates = OMAP_MCBSP_RATES,
                .formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S32_LE,
        },
        .ops = &mcbsp_dai_ops,
};

static const struct snd_soc_component_driver omap_mcbsp_component = {
        .name           = "omap-mcbsp",
};

static struct omap_mcbsp_platform_data omap2420_pdata = {
        .reg_step = 4,
        .reg_size = 2,
};

static struct omap_mcbsp_platform_data omap2430_pdata = {
        .reg_step = 4,
        .reg_size = 4,
        .has_ccr = true,
};

static struct omap_mcbsp_platform_data omap3_pdata = {
        .reg_step = 4,
        .reg_size = 4,
        .has_ccr = true,
        .has_wakeup = true,
};

static struct omap_mcbsp_platform_data omap4_pdata = {
        .reg_step = 4,
        .reg_size = 4,
        .has_ccr = true,
        .has_wakeup = true,
};

static const struct of_device_id omap_mcbsp_of_match[] = {
        {
                .compatible = "ti,omap2420-mcbsp",
                .data = &omap2420_pdata,
        },
        {
                .compatible = "ti,omap2430-mcbsp",
                .data = &omap2430_pdata,
        },
        {
                .compatible = "ti,omap3-mcbsp",
                .data = &omap3_pdata,
        },
        {
                .compatible = "ti,omap4-mcbsp",
                .data = &omap4_pdata,
        },
        { },
};
MODULE_DEVICE_TABLE(of, omap_mcbsp_of_match);

static int asoc_mcbsp_probe(struct platform_device *pdev)
{
        struct omap_mcbsp_platform_data *pdata = dev_get_platdata(&pdev->dev);
        struct omap_mcbsp *mcbsp;
        const struct of_device_id *match;
        int ret;

        match = of_match_device(omap_mcbsp_of_match, &pdev->dev);
        if (match) {
                struct device_node *node = pdev->dev.of_node;
                struct omap_mcbsp_platform_data *pdata_quirk = pdata;
                int buffer_size;

                pdata = devm_kzalloc(&pdev->dev,
                                     sizeof(struct omap_mcbsp_platform_data),
                                     GFP_KERNEL);
                if (!pdata)
                        return -ENOMEM;

                memcpy(pdata, match->data, sizeof(*pdata));
                if (!of_property_read_u32(node, "ti,buffer-size", &buffer_size))
                        pdata->buffer_size = buffer_size;
                if (pdata_quirk)
                        pdata->force_ick_on = pdata_quirk->force_ick_on;
        } else if (!pdata) {
                dev_err(&pdev->dev, "missing platform data.\n");
                return -EINVAL;
        }
        mcbsp = devm_kzalloc(&pdev->dev, sizeof(struct omap_mcbsp), GFP_KERNEL);
        if (!mcbsp)
                return -ENOMEM;

        mcbsp->id = pdev->id;
        mcbsp->pdata = pdata;
        mcbsp->dev = &pdev->dev;
        platform_set_drvdata(pdev, mcbsp);

        ret = omap_mcbsp_init(pdev);
        if (ret)
                return ret;

        if (mcbsp->pdata->reg_size == 2) {
                omap_mcbsp_dai.playback.formats = SNDRV_PCM_FMTBIT_S16_LE;
                omap_mcbsp_dai.capture.formats = SNDRV_PCM_FMTBIT_S16_LE;
        }

        ret = devm_snd_soc_register_component(&pdev->dev,
                                              &omap_mcbsp_component,
                                              &omap_mcbsp_dai, 1);
        if (ret)
                return ret;

        return sdma_pcm_platform_register(&pdev->dev, NULL, NULL);
}

static int asoc_mcbsp_remove(struct platform_device *pdev)
{
        struct omap_mcbsp *mcbsp = platform_get_drvdata(pdev);

        if (mcbsp->pdata->ops && mcbsp->pdata->ops->free)
                mcbsp->pdata->ops->free(mcbsp->id);

        if (pm_qos_request_active(&mcbsp->pm_qos_req))
                pm_qos_remove_request(&mcbsp->pm_qos_req);

        if (mcbsp->pdata->buffer_size)
                sysfs_remove_group(&mcbsp->dev->kobj, &additional_attr_group);

        omap_mcbsp_st_cleanup(pdev);

        clk_put(mcbsp->fclk);

        return 0;
}

static struct platform_driver asoc_mcbsp_driver = {
        .driver = {
                        .name = "omap-mcbsp",
                        .of_match_table = omap_mcbsp_of_match,
        },

        .probe = asoc_mcbsp_probe,
        .remove = asoc_mcbsp_remove,
};

module_platform_driver(asoc_mcbsp_driver);

MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@bitmer.com>");
MODULE_DESCRIPTION("OMAP I2S SoC Interface");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:omap-mcbsp");