Merge tag 'ceph-for-4.13-rc8' of git://github.com/ceph/ceph-client

[linux/fpc-iii.git] / drivers / mmc / host / renesas_sdhi_core.c

/*
 * Renesas SDHI
 *
 * Copyright (C) 2015-17 Renesas Electronics Corporation
 * Copyright (C) 2016-17 Sang Engineering, Wolfram Sang
 * Copyright (C) 2016-17 Horms Solutions, Simon Horman
 * Copyright (C) 2009 Magnus Damm
 *
 * 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.
 *
 * Based on "Compaq ASIC3 support":
 *
 * Copyright 2001 Compaq Computer Corporation.
 * Copyright 2004-2005 Phil Blundell
 * Copyright 2007-2008 OpenedHand Ltd.
 *
 * Authors: Phil Blundell <pb@handhelds.org>,
 *          Samuel Ortiz <sameo@openedhand.com>
 *
 */

#include <linux/kernel.h>
#include <linux/clk.h>
#include <linux/slab.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/mmc/host.h>
#include <linux/mfd/tmio.h>
#include <linux/sh_dma.h>
#include <linux/delay.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pinctrl/pinctrl-state.h>
#include <linux/regulator/consumer.h>

#include "renesas_sdhi.h"
#include "tmio_mmc.h"

#define EXT_ACC           0xe4

#define SDHI_VER_GEN2_SDR50     0x490c
/* very old datasheets said 0x490c for SDR104, too. They are wrong! */
#define SDHI_VER_GEN2_SDR104    0xcb0d
#define SDHI_VER_GEN3_SD        0xcc10
#define SDHI_VER_GEN3_SDMMC     0xcd10

#define host_to_priv(host) \
        container_of((host)->pdata, struct renesas_sdhi, mmc_data)

struct renesas_sdhi {
        struct clk *clk;
        struct clk *clk_cd;
        struct tmio_mmc_data mmc_data;
        struct tmio_mmc_dma dma_priv;
        struct pinctrl *pinctrl;
        struct pinctrl_state *pins_default, *pins_uhs;
        void __iomem *scc_ctl;
};

static void renesas_sdhi_sdbuf_width(struct tmio_mmc_host *host, int width)
{
        u32 val;

        /*
         * see also
         *      renesas_sdhi_of_data :: dma_buswidth
         */
        switch (sd_ctrl_read16(host, CTL_VERSION)) {
        case SDHI_VER_GEN2_SDR50:
                val = (width == 32) ? 0x0001 : 0x0000;
                break;
        case SDHI_VER_GEN2_SDR104:
                val = (width == 32) ? 0x0000 : 0x0001;
                break;
        case SDHI_VER_GEN3_SD:
        case SDHI_VER_GEN3_SDMMC:
                if (width == 64)
                        val = 0x0000;
                else if (width == 32)
                        val = 0x0101;
                else
                        val = 0x0001;
                break;
        default:
                /* nothing to do */
                return;
        }

        sd_ctrl_write16(host, EXT_ACC, val);
}

static int renesas_sdhi_clk_enable(struct tmio_mmc_host *host)
{
        struct mmc_host *mmc = host->mmc;
        struct renesas_sdhi *priv = host_to_priv(host);
        int ret = clk_prepare_enable(priv->clk);

        if (ret < 0)
                return ret;

        ret = clk_prepare_enable(priv->clk_cd);
        if (ret < 0) {
                clk_disable_unprepare(priv->clk);
                return ret;
        }

        /*
         * The clock driver may not know what maximum frequency
         * actually works, so it should be set with the max-frequency
         * property which will already have been read to f_max.  If it
         * was missing, assume the current frequency is the maximum.
         */
        if (!mmc->f_max)
                mmc->f_max = clk_get_rate(priv->clk);

        /*
         * Minimum frequency is the minimum input clock frequency
         * divided by our maximum divider.
         */
        mmc->f_min = max(clk_round_rate(priv->clk, 1) / 512, 1L);

        /* enable 16bit data access on SDBUF as default */
        renesas_sdhi_sdbuf_width(host, 16);

        return 0;
}

static unsigned int renesas_sdhi_clk_update(struct tmio_mmc_host *host,
                                            unsigned int new_clock)
{
        struct renesas_sdhi *priv = host_to_priv(host);
        unsigned int freq, diff, best_freq = 0, diff_min = ~0;
        int i, ret;

        /* tested only on R-Car Gen2+ currently; may work for others */
        if (!(host->pdata->flags & TMIO_MMC_MIN_RCAR2))
                return clk_get_rate(priv->clk);

        /*
         * We want the bus clock to be as close as possible to, but no
         * greater than, new_clock.  As we can divide by 1 << i for
         * any i in [0, 9] we want the input clock to be as close as
         * possible, but no greater than, new_clock << i.
         */
        for (i = min(9, ilog2(UINT_MAX / new_clock)); i >= 0; i--) {
                freq = clk_round_rate(priv->clk, new_clock << i);
                if (freq > (new_clock << i)) {
                        /* Too fast; look for a slightly slower option */
                        freq = clk_round_rate(priv->clk,
                                              (new_clock << i) / 4 * 3);
                        if (freq > (new_clock << i))
                                continue;
                }

                diff = new_clock - (freq >> i);
                if (diff <= diff_min) {
                        best_freq = freq;
                        diff_min = diff;
                }
        }

        ret = clk_set_rate(priv->clk, best_freq);

        return ret == 0 ? best_freq : clk_get_rate(priv->clk);
}

static void renesas_sdhi_clk_disable(struct tmio_mmc_host *host)
{
        struct renesas_sdhi *priv = host_to_priv(host);

        clk_disable_unprepare(priv->clk);
        clk_disable_unprepare(priv->clk_cd);
}

static int renesas_sdhi_card_busy(struct mmc_host *mmc)
{
        struct tmio_mmc_host *host = mmc_priv(mmc);

        return !(sd_ctrl_read16_and_16_as_32(host, CTL_STATUS) &
                 TMIO_STAT_DAT0);
}

static int renesas_sdhi_start_signal_voltage_switch(struct mmc_host *mmc,
                                                    struct mmc_ios *ios)
{
        struct tmio_mmc_host *host = mmc_priv(mmc);
        struct renesas_sdhi *priv = host_to_priv(host);
        struct pinctrl_state *pin_state;
        int ret;

        switch (ios->signal_voltage) {
        case MMC_SIGNAL_VOLTAGE_330:
                pin_state = priv->pins_default;
                break;
        case MMC_SIGNAL_VOLTAGE_180:
                pin_state = priv->pins_uhs;
                break;
        default:
                return -EINVAL;
        }

        /*
         * If anything is missing, assume signal voltage is fixed at
         * 3.3V and succeed/fail accordingly.
         */
        if (IS_ERR(priv->pinctrl) || IS_ERR(pin_state))
                return ios->signal_voltage ==
                        MMC_SIGNAL_VOLTAGE_330 ? 0 : -EINVAL;

        ret = mmc_regulator_set_vqmmc(host->mmc, ios);
        if (ret)
                return ret;

        return pinctrl_select_state(priv->pinctrl, pin_state);
}

/* SCC registers */
#define SH_MOBILE_SDHI_SCC_DTCNTL       0x000
#define SH_MOBILE_SDHI_SCC_TAPSET       0x002
#define SH_MOBILE_SDHI_SCC_DT2FF        0x004
#define SH_MOBILE_SDHI_SCC_CKSEL        0x006
#define SH_MOBILE_SDHI_SCC_RVSCNTL      0x008
#define SH_MOBILE_SDHI_SCC_RVSREQ       0x00A

/* Definitions for values the SH_MOBILE_SDHI_SCC_DTCNTL register */
#define SH_MOBILE_SDHI_SCC_DTCNTL_TAPEN         BIT(0)
#define SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT  16
#define SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_MASK   0xff

/* Definitions for values the SH_MOBILE_SDHI_SCC_CKSEL register */
#define SH_MOBILE_SDHI_SCC_CKSEL_DTSEL          BIT(0)
/* Definitions for values the SH_MOBILE_SDHI_SCC_RVSCNTL register */
#define SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN        BIT(0)
/* Definitions for values the SH_MOBILE_SDHI_SCC_RVSREQ register */
#define SH_MOBILE_SDHI_SCC_RVSREQ_RVSERR        BIT(2)

static inline u32 sd_scc_read32(struct tmio_mmc_host *host,
                                struct renesas_sdhi *priv, int addr)
{
        return readl(priv->scc_ctl + (addr << host->bus_shift));
}

static inline void sd_scc_write32(struct tmio_mmc_host *host,
                                  struct renesas_sdhi *priv,
                                  int addr, u32 val)
{
        writel(val, priv->scc_ctl + (addr << host->bus_shift));
}

static unsigned int renesas_sdhi_init_tuning(struct tmio_mmc_host *host)
{
        struct renesas_sdhi *priv;

        priv = host_to_priv(host);

        /* set sampling clock selection range */
        sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL,
                       0x8 << SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT);

        /* Initialize SCC */
        sd_ctrl_write32_as_16_and_16(host, CTL_STATUS, 0x0);

        sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL,
                       SH_MOBILE_SDHI_SCC_DTCNTL_TAPEN |
                       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL));

        sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
                        sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));

        sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL,
                       SH_MOBILE_SDHI_SCC_CKSEL_DTSEL |
                       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL));

        sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
                        sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));

        sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
                       ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &
                       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));

        sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_DT2FF, host->scc_tappos);

        /* Read TAPNUM */
        return (sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_DTCNTL) >>
                SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_SHIFT) &
                SH_MOBILE_SDHI_SCC_DTCNTL_TAPNUM_MASK;
}

static void renesas_sdhi_prepare_tuning(struct tmio_mmc_host *host,
                                        unsigned long tap)
{
        struct renesas_sdhi *priv = host_to_priv(host);

        /* Set sampling clock position */
        sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TAPSET, tap);
}

#define SH_MOBILE_SDHI_MAX_TAP 3

static int renesas_sdhi_select_tuning(struct tmio_mmc_host *host)
{
        struct renesas_sdhi *priv = host_to_priv(host);
        unsigned long tap_cnt;  /* counter of tuning success */
        unsigned long tap_set;  /* tap position */
        unsigned long tap_start;/* start position of tuning success */
        unsigned long tap_end;  /* end position of tuning success */
        unsigned long ntap;     /* temporary counter of tuning success */
        unsigned long i;

        /* Clear SCC_RVSREQ */
        sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ, 0);

        /*
         * Find the longest consecutive run of successful probes.  If that
         * is more than SH_MOBILE_SDHI_MAX_TAP probes long then use the
         * center index as the tap.
         */
        tap_cnt = 0;
        ntap = 0;
        tap_start = 0;
        tap_end = 0;
        for (i = 0; i < host->tap_num * 2; i++) {
                if (test_bit(i, host->taps)) {
                        ntap++;
                } else {
                        if (ntap > tap_cnt) {
                                tap_start = i - ntap;
                                tap_end = i - 1;
                                tap_cnt = ntap;
                        }
                        ntap = 0;
                }
        }

        if (ntap > tap_cnt) {
                tap_start = i - ntap;
                tap_end = i - 1;
                tap_cnt = ntap;
        }

        if (tap_cnt >= SH_MOBILE_SDHI_MAX_TAP)
                tap_set = (tap_start + tap_end) / 2 % host->tap_num;
        else
                return -EIO;

        /* Set SCC */
        sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_TAPSET, tap_set);

        /* Enable auto re-tuning */
        sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
                       SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN |
                       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));

        return 0;
}

static bool renesas_sdhi_check_scc_error(struct tmio_mmc_host *host)
{
        struct renesas_sdhi *priv = host_to_priv(host);

        /* Check SCC error */
        if (sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL) &
            SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &&
            sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ) &
            SH_MOBILE_SDHI_SCC_RVSREQ_RVSERR) {
                /* Clear SCC error */
                sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ, 0);
                return true;
        }

        return false;
}

static void renesas_sdhi_hw_reset(struct tmio_mmc_host *host)
{
        struct renesas_sdhi *priv;

        priv = host_to_priv(host);

        /* Reset SCC */
        sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
                        sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));

        sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL,
                       ~SH_MOBILE_SDHI_SCC_CKSEL_DTSEL &
                       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_CKSEL));

        sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
                        sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));

        sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
                       ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &
                       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));

        sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL,
                       ~SH_MOBILE_SDHI_SCC_RVSCNTL_RVSEN &
                       sd_scc_read32(host, priv, SH_MOBILE_SDHI_SCC_RVSCNTL));
}

static int renesas_sdhi_wait_idle(struct tmio_mmc_host *host)
{
        int timeout = 1000;

        while (--timeout && !(sd_ctrl_read16_and_16_as_32(host, CTL_STATUS)
                              & TMIO_STAT_SCLKDIVEN))
                udelay(1);

        if (!timeout) {
                dev_warn(&host->pdev->dev, "timeout waiting for SD bus idle\n");
                return -EBUSY;
        }

        return 0;
}

static int renesas_sdhi_write16_hook(struct tmio_mmc_host *host, int addr)
{
        switch (addr) {
        case CTL_SD_CMD:
        case CTL_STOP_INTERNAL_ACTION:
        case CTL_XFER_BLK_COUNT:
        case CTL_SD_CARD_CLK_CTL:
        case CTL_SD_XFER_LEN:
        case CTL_SD_MEM_CARD_OPT:
        case CTL_TRANSACTION_CTL:
        case CTL_DMA_ENABLE:
        case EXT_ACC:
                return renesas_sdhi_wait_idle(host);
        }

        return 0;
}

static int renesas_sdhi_multi_io_quirk(struct mmc_card *card,
                                       unsigned int direction, int blk_size)
{
        /*
         * In Renesas controllers, when performing a
         * multiple block read of one or two blocks,
         * depending on the timing with which the
         * response register is read, the response
         * value may not be read properly.
         * Use single block read for this HW bug
         */
        if ((direction == MMC_DATA_READ) &&
            blk_size == 2)
                return 1;

        return blk_size;
}

static void renesas_sdhi_enable_dma(struct tmio_mmc_host *host, bool enable)
{
        sd_ctrl_write16(host, CTL_DMA_ENABLE, enable ? 2 : 0);

        /* enable 32bit access if DMA mode if possibile */
        renesas_sdhi_sdbuf_width(host, enable ? 32 : 16);
}

int renesas_sdhi_probe(struct platform_device *pdev,
                       const struct tmio_mmc_dma_ops *dma_ops)
{
        struct tmio_mmc_data *mmd = pdev->dev.platform_data;
        const struct renesas_sdhi_of_data *of_data;
        struct tmio_mmc_data *mmc_data;
        struct tmio_mmc_dma *dma_priv;
        struct tmio_mmc_host *host;
        struct renesas_sdhi *priv;
        struct resource *res;
        int irq, ret, i;

        of_data = of_device_get_match_data(&pdev->dev);

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!res)
                return -EINVAL;

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

        mmc_data = &priv->mmc_data;
        dma_priv = &priv->dma_priv;

        priv->clk = devm_clk_get(&pdev->dev, NULL);
        if (IS_ERR(priv->clk)) {
                ret = PTR_ERR(priv->clk);
                dev_err(&pdev->dev, "cannot get clock: %d\n", ret);
                goto eprobe;
        }

        /*
         * Some controllers provide a 2nd clock just to run the internal card
         * detection logic. Unfortunately, the existing driver architecture does
         * not support a separation of clocks for runtime PM usage. When
         * native hotplug is used, the tmio driver assumes that the core
         * must continue to run for card detect to stay active, so we cannot
         * disable it.
         * Additionally, it is prohibited to supply a clock to the core but not
         * to the card detect circuit. That leaves us with if separate clocks
         * are presented, we must treat them both as virtually 1 clock.
         */
        priv->clk_cd = devm_clk_get(&pdev->dev, "cd");
        if (IS_ERR(priv->clk_cd))
                priv->clk_cd = NULL;

        priv->pinctrl = devm_pinctrl_get(&pdev->dev);
        if (!IS_ERR(priv->pinctrl)) {
                priv->pins_default = pinctrl_lookup_state(priv->pinctrl,
                                                PINCTRL_STATE_DEFAULT);
                priv->pins_uhs = pinctrl_lookup_state(priv->pinctrl,
                                                "state_uhs");
        }

        host = tmio_mmc_host_alloc(pdev);
        if (!host) {
                ret = -ENOMEM;
                goto eprobe;
        }

        if (of_data) {
                mmc_data->flags |= of_data->tmio_flags;
                mmc_data->ocr_mask = of_data->tmio_ocr_mask;
                mmc_data->capabilities |= of_data->capabilities;
                mmc_data->capabilities2 |= of_data->capabilities2;
                mmc_data->dma_rx_offset = of_data->dma_rx_offset;
                dma_priv->dma_buswidth = of_data->dma_buswidth;
                host->bus_shift = of_data->bus_shift;
        }

        host->dma               = dma_priv;
        host->write16_hook      = renesas_sdhi_write16_hook;
        host->clk_enable        = renesas_sdhi_clk_enable;
        host->clk_update        = renesas_sdhi_clk_update;
        host->clk_disable       = renesas_sdhi_clk_disable;
        host->multi_io_quirk    = renesas_sdhi_multi_io_quirk;

        /* SDR speeds are only available on Gen2+ */
        if (mmc_data->flags & TMIO_MMC_MIN_RCAR2) {
                /* card_busy caused issues on r8a73a4 (pre-Gen2) CD-less SDHI */
                host->card_busy = renesas_sdhi_card_busy;
                host->start_signal_voltage_switch =
                        renesas_sdhi_start_signal_voltage_switch;
        }

        /* Orginally registers were 16 bit apart, could be 32 or 64 nowadays */
        if (!host->bus_shift && resource_size(res) > 0x100) /* old way to determine the shift */
                host->bus_shift = 1;

        if (mmd)
                *mmc_data = *mmd;

        dma_priv->filter = shdma_chan_filter;
        dma_priv->enable = renesas_sdhi_enable_dma;

        mmc_data->alignment_shift = 1; /* 2-byte alignment */
        mmc_data->capabilities |= MMC_CAP_MMC_HIGHSPEED;

        /*
         * All SDHI blocks support 2-byte and larger block sizes in 4-bit
         * bus width mode.
         */
        mmc_data->flags |= TMIO_MMC_BLKSZ_2BYTES;

        /*
         * All SDHI blocks support SDIO IRQ signalling.
         */
        mmc_data->flags |= TMIO_MMC_SDIO_IRQ;

        /* All SDHI have CMD12 control bit */
        mmc_data->flags |= TMIO_MMC_HAVE_CMD12_CTRL;

        /* All SDHI have SDIO status bits which must be 1 */
        mmc_data->flags |= TMIO_MMC_SDIO_STATUS_SETBITS;

        ret = tmio_mmc_host_probe(host, mmc_data, dma_ops);
        if (ret < 0)
                goto efree;

        /* Enable tuning iff we have an SCC and a supported mode */
        if (of_data && of_data->scc_offset &&
            (host->mmc->caps & MMC_CAP_UHS_SDR104 ||
             host->mmc->caps2 & MMC_CAP2_HS200_1_8V_SDR)) {
                const struct renesas_sdhi_scc *taps = of_data->taps;
                bool hit = false;

                host->mmc->caps |= MMC_CAP_HW_RESET;

                for (i = 0; i < of_data->taps_num; i++) {
                        if (taps[i].clk_rate == 0 ||
                            taps[i].clk_rate == host->mmc->f_max) {
                                host->scc_tappos = taps->tap;
                                hit = true;
                                break;
                        }
                }

                if (!hit)
                        dev_warn(&host->pdev->dev, "Unknown clock rate for SDR104\n");

                priv->scc_ctl = host->ctl + of_data->scc_offset;
                host->init_tuning = renesas_sdhi_init_tuning;
                host->prepare_tuning = renesas_sdhi_prepare_tuning;
                host->select_tuning = renesas_sdhi_select_tuning;
                host->check_scc_error = renesas_sdhi_check_scc_error;
                host->hw_reset = renesas_sdhi_hw_reset;
        }

        i = 0;
        while (1) {
                irq = platform_get_irq(pdev, i);
                if (irq < 0)
                        break;
                i++;
                ret = devm_request_irq(&pdev->dev, irq, tmio_mmc_irq, 0,
                                       dev_name(&pdev->dev), host);
                if (ret)
                        goto eirq;
        }

        /* There must be at least one IRQ source */
        if (!i) {
                ret = irq;
                goto eirq;
        }

        dev_info(&pdev->dev, "%s base at 0x%08lx max clock rate %u MHz\n",
                 mmc_hostname(host->mmc), (unsigned long)
                 (platform_get_resource(pdev, IORESOURCE_MEM, 0)->start),
                 host->mmc->f_max / 1000000);

        return ret;

eirq:
        tmio_mmc_host_remove(host);
efree:
        tmio_mmc_host_free(host);
eprobe:
        return ret;
}
EXPORT_SYMBOL_GPL(renesas_sdhi_probe);

int renesas_sdhi_remove(struct platform_device *pdev)
{
        struct mmc_host *mmc = platform_get_drvdata(pdev);
        struct tmio_mmc_host *host = mmc_priv(mmc);

        tmio_mmc_host_remove(host);

        return 0;
}
EXPORT_SYMBOL_GPL(renesas_sdhi_remove);