Merge tag 'trace-printf-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/trace...

[drm/drm-misc.git] / drivers / mmc / host / sdhci-xenon.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Driver for Marvell Xenon SDHC as a platform device
 *
 * Copyright (C) 2016 Marvell, All Rights Reserved.
 *
 * Author:      Hu Ziji <huziji@marvell.com>
 * Date:        2016-8-24
 *
 * Inspired by Jisheng Zhang <jszhang@marvell.com>
 * Special thanks to Video BG4 project team.
 */

#include <linux/acpi.h>
#include <linux/delay.h>
#include <linux/ktime.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
#include <linux/mm.h>
#include <linux/dma-mapping.h>

#include "sdhci-pltfm.h"
#include "sdhci-xenon.h"

static int xenon_enable_internal_clk(struct sdhci_host *host)
{
        u32 reg;
        ktime_t timeout;

        reg = sdhci_readl(host, SDHCI_CLOCK_CONTROL);
        reg |= SDHCI_CLOCK_INT_EN;
        sdhci_writel(host, reg, SDHCI_CLOCK_CONTROL);
        /* Wait max 20 ms */
        timeout = ktime_add_ms(ktime_get(), 20);
        while (1) {
                bool timedout = ktime_after(ktime_get(), timeout);

                reg = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
                if (reg & SDHCI_CLOCK_INT_STABLE)
                        break;
                if (timedout) {
                        dev_err(mmc_dev(host->mmc), "Internal clock never stabilised.\n");
                        return -ETIMEDOUT;
                }
                usleep_range(900, 1100);
        }

        return 0;
}

/* Set SDCLK-off-while-idle */
static void xenon_set_sdclk_off_idle(struct sdhci_host *host,
                                     unsigned char sdhc_id, bool enable)
{
        u32 reg;
        u32 mask;

        reg = sdhci_readl(host, XENON_SYS_OP_CTRL);
        /* Get the bit shift basing on the SDHC index */
        mask = (0x1 << (XENON_SDCLK_IDLEOFF_ENABLE_SHIFT + sdhc_id));
        if (enable)
                reg |= mask;
        else
                reg &= ~mask;

        sdhci_writel(host, reg, XENON_SYS_OP_CTRL);
}

/* Enable/Disable the Auto Clock Gating function */
static void xenon_set_acg(struct sdhci_host *host, bool enable)
{
        u32 reg;

        reg = sdhci_readl(host, XENON_SYS_OP_CTRL);
        if (enable)
                reg &= ~XENON_AUTO_CLKGATE_DISABLE_MASK;
        else
                reg |= XENON_AUTO_CLKGATE_DISABLE_MASK;
        sdhci_writel(host, reg, XENON_SYS_OP_CTRL);
}

/* Enable this SDHC */
static void xenon_enable_sdhc(struct sdhci_host *host,
                              unsigned char sdhc_id)
{
        u32 reg;

        reg = sdhci_readl(host, XENON_SYS_OP_CTRL);
        reg |= (BIT(sdhc_id) << XENON_SLOT_ENABLE_SHIFT);
        sdhci_writel(host, reg, XENON_SYS_OP_CTRL);

        host->mmc->caps |= MMC_CAP_WAIT_WHILE_BUSY;
        /*
         * Force to clear BUS_TEST to
         * skip bus_test_pre and bus_test_post
         */
        host->mmc->caps &= ~MMC_CAP_BUS_WIDTH_TEST;
}

/* Disable this SDHC */
static void xenon_disable_sdhc(struct sdhci_host *host,
                               unsigned char sdhc_id)
{
        u32 reg;

        reg = sdhci_readl(host, XENON_SYS_OP_CTRL);
        reg &= ~(BIT(sdhc_id) << XENON_SLOT_ENABLE_SHIFT);
        sdhci_writel(host, reg, XENON_SYS_OP_CTRL);
}

/* Enable Parallel Transfer Mode */
static void xenon_enable_sdhc_parallel_tran(struct sdhci_host *host,
                                            unsigned char sdhc_id)
{
        u32 reg;

        reg = sdhci_readl(host, XENON_SYS_EXT_OP_CTRL);
        reg |= BIT(sdhc_id);
        sdhci_writel(host, reg, XENON_SYS_EXT_OP_CTRL);
}

/* Mask command conflict error */
static void xenon_mask_cmd_conflict_err(struct sdhci_host *host)
{
        u32  reg;

        reg = sdhci_readl(host, XENON_SYS_EXT_OP_CTRL);
        reg |= XENON_MASK_CMD_CONFLICT_ERR;
        sdhci_writel(host, reg, XENON_SYS_EXT_OP_CTRL);
}

static void xenon_retune_setup(struct sdhci_host *host)
{
        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
        struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
        u32 reg;

        /* Disable the Re-Tuning Request functionality */
        reg = sdhci_readl(host, XENON_SLOT_RETUNING_REQ_CTRL);
        reg &= ~XENON_RETUNING_COMPATIBLE;
        sdhci_writel(host, reg, XENON_SLOT_RETUNING_REQ_CTRL);

        /* Disable the Re-tuning Interrupt */
        reg = sdhci_readl(host, SDHCI_SIGNAL_ENABLE);
        reg &= ~SDHCI_INT_RETUNE;
        sdhci_writel(host, reg, SDHCI_SIGNAL_ENABLE);
        reg = sdhci_readl(host, SDHCI_INT_ENABLE);
        reg &= ~SDHCI_INT_RETUNE;
        sdhci_writel(host, reg, SDHCI_INT_ENABLE);

        /* Force to use Tuning Mode 1 */
        host->tuning_mode = SDHCI_TUNING_MODE_1;
        /* Set re-tuning period */
        host->tuning_count = 1 << (priv->tuning_count - 1);
}

/*
 * Operations inside struct sdhci_ops
 */
/* Recover the Register Setting cleared during SOFTWARE_RESET_ALL */
static void xenon_reset_exit(struct sdhci_host *host,
                             unsigned char sdhc_id, u8 mask)
{
        /* Only SOFTWARE RESET ALL will clear the register setting */
        if (!(mask & SDHCI_RESET_ALL))
                return;

        /* Disable tuning request and auto-retuning again */
        xenon_retune_setup(host);

        /*
         * The ACG should be turned off at the early init time, in order
         * to solve a possible issues with the 1.8V regulator stabilization.
         * The feature is enabled in later stage.
         */
        xenon_set_acg(host, false);

        xenon_set_sdclk_off_idle(host, sdhc_id, false);

        xenon_mask_cmd_conflict_err(host);
}

static void xenon_reset(struct sdhci_host *host, u8 mask)
{
        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
        struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);

        sdhci_reset(host, mask);
        xenon_reset_exit(host, priv->sdhc_id, mask);
}

/*
 * Xenon defines different values for HS200 and HS400
 * in Host_Control_2
 */
static void xenon_set_uhs_signaling(struct sdhci_host *host,
                                    unsigned int timing)
{
        u16 ctrl_2;

        ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
        /* Select Bus Speed Mode for host */
        ctrl_2 &= ~SDHCI_CTRL_UHS_MASK;
        if (timing == MMC_TIMING_MMC_HS200)
                ctrl_2 |= XENON_CTRL_HS200;
        else if (timing == MMC_TIMING_UHS_SDR104)
                ctrl_2 |= SDHCI_CTRL_UHS_SDR104;
        else if (timing == MMC_TIMING_UHS_SDR12)
                ctrl_2 |= SDHCI_CTRL_UHS_SDR12;
        else if (timing == MMC_TIMING_UHS_SDR25)
                ctrl_2 |= SDHCI_CTRL_UHS_SDR25;
        else if (timing == MMC_TIMING_UHS_SDR50)
                ctrl_2 |= SDHCI_CTRL_UHS_SDR50;
        else if ((timing == MMC_TIMING_UHS_DDR50) ||
                 (timing == MMC_TIMING_MMC_DDR52))
                ctrl_2 |= SDHCI_CTRL_UHS_DDR50;
        else if (timing == MMC_TIMING_MMC_HS400)
                ctrl_2 |= XENON_CTRL_HS400;
        sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
}

static void xenon_set_power(struct sdhci_host *host, unsigned char mode,
                unsigned short vdd)
{
        struct mmc_host *mmc = host->mmc;
        u8 pwr = host->pwr;

        sdhci_set_power_noreg(host, mode, vdd);

        if (host->pwr == pwr)
                return;

        if (host->pwr == 0)
                vdd = 0;

        if (!IS_ERR(mmc->supply.vmmc))
                mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, vdd);
}

static void xenon_voltage_switch(struct sdhci_host *host)
{
        /* Wait for 5ms after set 1.8V signal enable bit */
        usleep_range(5000, 5500);
}

static unsigned int xenon_get_max_clock(struct sdhci_host *host)
{
        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);

        if (pltfm_host->clk)
                return sdhci_pltfm_clk_get_max_clock(host);
        else
                return pltfm_host->clock;
}

static const struct sdhci_ops sdhci_xenon_ops = {
        .voltage_switch         = xenon_voltage_switch,
        .set_clock              = sdhci_set_clock,
        .set_power              = xenon_set_power,
        .set_bus_width          = sdhci_set_bus_width,
        .reset                  = xenon_reset,
        .set_uhs_signaling      = xenon_set_uhs_signaling,
        .get_max_clock          = xenon_get_max_clock,
};

static const struct sdhci_pltfm_data sdhci_xenon_pdata = {
        .ops = &sdhci_xenon_ops,
        .quirks = SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC |
                  SDHCI_QUIRK_NO_SIMULT_VDD_AND_POWER |
                  SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
};

/*
 * Xenon Specific Operations in mmc_host_ops
 */
static void xenon_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
{
        struct sdhci_host *host = mmc_priv(mmc);
        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
        struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
        u32 reg;

        /*
         * HS400/HS200/eMMC HS doesn't have Preset Value register.
         * However, sdhci_set_ios will read HS400/HS200 Preset register.
         * Disable Preset Value register for HS400/HS200.
         * eMMC HS with preset_enabled set will trigger a bug in
         * get_preset_value().
         */
        if ((ios->timing == MMC_TIMING_MMC_HS400) ||
            (ios->timing == MMC_TIMING_MMC_HS200) ||
            (ios->timing == MMC_TIMING_MMC_HS)) {
                host->preset_enabled = false;
                host->quirks2 |= SDHCI_QUIRK2_PRESET_VALUE_BROKEN;
                host->flags &= ~SDHCI_PV_ENABLED;

                reg = sdhci_readw(host, SDHCI_HOST_CONTROL2);
                reg &= ~SDHCI_CTRL_PRESET_VAL_ENABLE;
                sdhci_writew(host, reg, SDHCI_HOST_CONTROL2);
        } else {
                host->quirks2 &= ~SDHCI_QUIRK2_PRESET_VALUE_BROKEN;
        }

        sdhci_set_ios(mmc, ios);
        xenon_phy_adj(host, ios);

        if (host->clock > XENON_DEFAULT_SDCLK_FREQ)
                xenon_set_sdclk_off_idle(host, priv->sdhc_id, true);
}

static int xenon_start_signal_voltage_switch(struct mmc_host *mmc,
                                             struct mmc_ios *ios)
{
        struct sdhci_host *host = mmc_priv(mmc);

        /*
         * Before SD/SDIO set signal voltage, SD bus clock should be
         * disabled. However, sdhci_set_clock will also disable the Internal
         * clock in mmc_set_signal_voltage().
         * If Internal clock is disabled, the 3.3V/1.8V bit can not be updated.
         * Thus here manually enable internal clock.
         *
         * After switch completes, it is unnecessary to disable internal clock,
         * since keeping internal clock active obeys SD spec.
         */
        xenon_enable_internal_clk(host);

        xenon_soc_pad_ctrl(host, ios->signal_voltage);

        /*
         * If Vqmmc is fixed on platform, vqmmc regulator should be unavailable.
         * Thus SDHCI_CTRL_VDD_180 bit might not work then.
         * Skip the standard voltage switch to avoid any issue.
         */
        if (PTR_ERR(mmc->supply.vqmmc) == -ENODEV)
                return 0;

        return sdhci_start_signal_voltage_switch(mmc, ios);
}

/*
 * Update card type.
 * priv->init_card_type will be used in PHY timing adjustment.
 */
static void xenon_init_card(struct mmc_host *mmc, struct mmc_card *card)
{
        struct sdhci_host *host = mmc_priv(mmc);
        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
        struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);

        /* Update card type*/
        priv->init_card_type = card->type;
}

static int xenon_execute_tuning(struct mmc_host *mmc, u32 opcode)
{
        struct sdhci_host *host = mmc_priv(mmc);

        if (host->timing == MMC_TIMING_UHS_DDR50 ||
                host->timing == MMC_TIMING_MMC_DDR52)
                return 0;

        /*
         * Currently force Xenon driver back to support mode 1 only,
         * even though Xenon might claim to support mode 2 or mode 3.
         * It requires more time to test mode 2/mode 3 on more platforms.
         */
        if (host->tuning_mode != SDHCI_TUNING_MODE_1)
                xenon_retune_setup(host);

        return sdhci_execute_tuning(mmc, opcode);
}

static void xenon_enable_sdio_irq(struct mmc_host *mmc, int enable)
{
        struct sdhci_host *host = mmc_priv(mmc);
        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
        struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
        u32 reg;
        u8 sdhc_id = priv->sdhc_id;

        sdhci_enable_sdio_irq(mmc, enable);

        if (enable) {
                /*
                 * Set SDIO Card Inserted indication
                 * to enable detecting SDIO async irq.
                 */
                reg = sdhci_readl(host, XENON_SYS_CFG_INFO);
                reg |= (1 << (sdhc_id + XENON_SLOT_TYPE_SDIO_SHIFT));
                sdhci_writel(host, reg, XENON_SYS_CFG_INFO);
        } else {
                /* Clear SDIO Card Inserted indication */
                reg = sdhci_readl(host, XENON_SYS_CFG_INFO);
                reg &= ~(1 << (sdhc_id + XENON_SLOT_TYPE_SDIO_SHIFT));
                sdhci_writel(host, reg, XENON_SYS_CFG_INFO);
        }
}

static void xenon_replace_mmc_host_ops(struct sdhci_host *host)
{
        host->mmc_host_ops.set_ios = xenon_set_ios;
        host->mmc_host_ops.start_signal_voltage_switch =
                        xenon_start_signal_voltage_switch;
        host->mmc_host_ops.init_card = xenon_init_card;
        host->mmc_host_ops.execute_tuning = xenon_execute_tuning;
        host->mmc_host_ops.enable_sdio_irq = xenon_enable_sdio_irq;
}

/*
 * Parse Xenon specific DT properties:
 * sdhc-id: the index of current SDHC.
 *          Refer to XENON_SYS_CFG_INFO register
 * tun-count: the interval between re-tuning
 */
static int xenon_probe_params(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct sdhci_host *host = platform_get_drvdata(pdev);
        struct mmc_host *mmc = host->mmc;
        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
        struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
        u32 sdhc_id, nr_sdhc;
        u32 tuning_count;
        struct sysinfo si;

        /* Disable HS200 on Armada AP806 */
        if (priv->hw_version == XENON_AP806)
                host->quirks2 |= SDHCI_QUIRK2_BROKEN_HS200;

        sdhc_id = 0x0;
        if (!device_property_read_u32(dev, "marvell,xenon-sdhc-id", &sdhc_id)) {
                nr_sdhc = sdhci_readl(host, XENON_SYS_CFG_INFO);
                nr_sdhc &= XENON_NR_SUPPORTED_SLOT_MASK;
                if (unlikely(sdhc_id > nr_sdhc)) {
                        dev_err(mmc_dev(mmc), "SDHC Index %d exceeds Number of SDHCs %d\n",
                                sdhc_id, nr_sdhc);
                        return -EINVAL;
                }
        }
        priv->sdhc_id = sdhc_id;

        tuning_count = XENON_DEF_TUNING_COUNT;
        if (!device_property_read_u32(dev, "marvell,xenon-tun-count",
                                      &tuning_count)) {
                if (unlikely(tuning_count >= XENON_TMR_RETUN_NO_PRESENT)) {
                        dev_err(mmc_dev(mmc), "Wrong Re-tuning Count. Set default value %d\n",
                                XENON_DEF_TUNING_COUNT);
                        tuning_count = XENON_DEF_TUNING_COUNT;
                }
        }
        priv->tuning_count = tuning_count;

        /*
         * AC5/X/IM HW has only 31-bits passed in the crossbar switch.
         * If we have more than 2GB of memory, this means we might pass
         * memory pointers which are above 2GB and which cannot be properly
         * represented. In this case, disable ADMA, 64-bit DMA and allow only SDMA.
         * This effectively will enable bounce buffer quirk in the
         * generic SDHCI driver, which will make sure DMA is only done
         * from supported memory regions:
         */
        if (priv->hw_version == XENON_AC5) {
                si_meminfo(&si);
                if (si.totalram * si.mem_unit > SZ_2G) {
                        host->quirks |= SDHCI_QUIRK_BROKEN_ADMA;
                        host->quirks2 |= SDHCI_QUIRK2_BROKEN_64_BIT_DMA;
                }
        }

        return xenon_phy_parse_params(dev, host);
}

static int xenon_sdhc_prepare(struct sdhci_host *host)
{
        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
        struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
        u8 sdhc_id = priv->sdhc_id;

        /* Enable SDHC */
        xenon_enable_sdhc(host, sdhc_id);

        /* Enable ACG */
        xenon_set_acg(host, true);

        /* Enable Parallel Transfer Mode */
        xenon_enable_sdhc_parallel_tran(host, sdhc_id);

        /* Disable SDCLK-Off-While-Idle before card init */
        xenon_set_sdclk_off_idle(host, sdhc_id, false);

        xenon_mask_cmd_conflict_err(host);

        return 0;
}

static void xenon_sdhc_unprepare(struct sdhci_host *host)
{
        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
        struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
        u8 sdhc_id = priv->sdhc_id;

        /* disable SDHC */
        xenon_disable_sdhc(host, sdhc_id);
}

static int xenon_probe(struct platform_device *pdev)
{
        struct sdhci_pltfm_host *pltfm_host;
        struct device *dev = &pdev->dev;
        struct sdhci_host *host;
        struct xenon_priv *priv;
        int err;

        host = sdhci_pltfm_init(pdev, &sdhci_xenon_pdata,
                                sizeof(struct xenon_priv));
        if (IS_ERR(host))
                return PTR_ERR(host);

        pltfm_host = sdhci_priv(host);
        priv = sdhci_pltfm_priv(pltfm_host);

        priv->hw_version = (unsigned long)device_get_match_data(&pdev->dev);

        /*
         * Link Xenon specific mmc_host_ops function,
         * to replace standard ones in sdhci_ops.
         */
        xenon_replace_mmc_host_ops(host);

        if (dev->of_node) {
                pltfm_host->clk = devm_clk_get(&pdev->dev, "core");
                if (IS_ERR(pltfm_host->clk)) {
                        err = PTR_ERR(pltfm_host->clk);
                        dev_err(&pdev->dev, "Failed to setup input clk: %d\n", err);
                        goto free_pltfm;
                }
                err = clk_prepare_enable(pltfm_host->clk);
                if (err)
                        goto free_pltfm;

                priv->axi_clk = devm_clk_get(&pdev->dev, "axi");
                if (IS_ERR(priv->axi_clk)) {
                        err = PTR_ERR(priv->axi_clk);
                        if (err == -EPROBE_DEFER)
                                goto err_clk;
                } else {
                        err = clk_prepare_enable(priv->axi_clk);
                        if (err)
                                goto err_clk;
                }
        }

        err = mmc_of_parse(host->mmc);
        if (err)
                goto err_clk_axi;

        sdhci_get_property(pdev);

        xenon_set_acg(host, false);

        /* Xenon specific parameters parse */
        err = xenon_probe_params(pdev);
        if (err)
                goto err_clk_axi;

        err = xenon_sdhc_prepare(host);
        if (err)
                goto err_clk_axi;

        pm_runtime_get_noresume(&pdev->dev);
        pm_runtime_set_active(&pdev->dev);
        pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
        pm_runtime_use_autosuspend(&pdev->dev);
        pm_runtime_enable(&pdev->dev);
        pm_suspend_ignore_children(&pdev->dev, 1);

        err = sdhci_add_host(host);
        if (err)
                goto remove_sdhc;

        pm_runtime_put_autosuspend(&pdev->dev);
        /*
         * If we previously detected AC5 with over 2GB of memory,
         * then we disable ADMA and 64-bit DMA.
         * This means generic SDHCI driver has set the DMA mask to
         * 32-bit. Since DDR starts at 0x2_0000_0000, we must use
         * 34-bit DMA mask to access this DDR memory:
         */
        if (priv->hw_version == XENON_AC5 &&
            host->quirks2 & SDHCI_QUIRK2_BROKEN_64_BIT_DMA)
                dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(34));

        return 0;

remove_sdhc:
        pm_runtime_disable(&pdev->dev);
        pm_runtime_put_noidle(&pdev->dev);
        xenon_sdhc_unprepare(host);
err_clk_axi:
        clk_disable_unprepare(priv->axi_clk);
err_clk:
        clk_disable_unprepare(pltfm_host->clk);
free_pltfm:
        sdhci_pltfm_free(pdev);
        return err;
}

static void xenon_remove(struct platform_device *pdev)
{
        struct sdhci_host *host = platform_get_drvdata(pdev);
        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
        struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);

        pm_runtime_get_sync(&pdev->dev);
        pm_runtime_disable(&pdev->dev);
        pm_runtime_put_noidle(&pdev->dev);

        sdhci_remove_host(host, 0);

        xenon_sdhc_unprepare(host);
        clk_disable_unprepare(priv->axi_clk);
        clk_disable_unprepare(pltfm_host->clk);

        sdhci_pltfm_free(pdev);
}

#ifdef CONFIG_PM_SLEEP
static int xenon_suspend(struct device *dev)
{
        struct sdhci_host *host = dev_get_drvdata(dev);
        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
        struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
        int ret;

        ret = pm_runtime_force_suspend(dev);

        priv->restore_needed = true;
        return ret;
}
#endif

#ifdef CONFIG_PM
static int xenon_runtime_suspend(struct device *dev)
{
        struct sdhci_host *host = dev_get_drvdata(dev);
        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
        struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
        int ret;

        ret = sdhci_runtime_suspend_host(host);
        if (ret)
                return ret;

        if (host->tuning_mode != SDHCI_TUNING_MODE_3)
                mmc_retune_needed(host->mmc);

        clk_disable_unprepare(pltfm_host->clk);
        /*
         * Need to update the priv->clock here, or when runtime resume
         * back, phy don't aware the clock change and won't adjust phy
         * which will cause cmd err
         */
        priv->clock = 0;
        return 0;
}

static int xenon_runtime_resume(struct device *dev)
{
        struct sdhci_host *host = dev_get_drvdata(dev);
        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
        struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
        int ret;

        ret = clk_prepare_enable(pltfm_host->clk);
        if (ret) {
                dev_err(dev, "can't enable mainck\n");
                return ret;
        }

        if (priv->restore_needed) {
                ret = xenon_sdhc_prepare(host);
                if (ret)
                        goto out;
                priv->restore_needed = false;
        }

        ret = sdhci_runtime_resume_host(host, 0);
        if (ret)
                goto out;
        return 0;
out:
        clk_disable_unprepare(pltfm_host->clk);
        return ret;
}
#endif /* CONFIG_PM */

static const struct dev_pm_ops sdhci_xenon_dev_pm_ops = {
        SET_SYSTEM_SLEEP_PM_OPS(xenon_suspend,
                                pm_runtime_force_resume)
        SET_RUNTIME_PM_OPS(xenon_runtime_suspend,
                           xenon_runtime_resume,
                           NULL)
};

static const struct of_device_id sdhci_xenon_dt_ids[] = {
        { .compatible = "marvell,armada-ap806-sdhci", .data = (void *)XENON_AP806},
        { .compatible = "marvell,armada-ap807-sdhci", .data = (void *)XENON_AP807},
        { .compatible = "marvell,armada-cp110-sdhci", .data =  (void *)XENON_CP110},
        { .compatible = "marvell,armada-3700-sdhci", .data =  (void *)XENON_A3700},
        { .compatible = "marvell,ac5-sdhci",         .data =  (void *)XENON_AC5},
        {}
};
MODULE_DEVICE_TABLE(of, sdhci_xenon_dt_ids);

#ifdef CONFIG_ACPI
static const struct acpi_device_id sdhci_xenon_acpi_ids[] = {
        { .id = "MRVL0002", XENON_AP806},
        { .id = "MRVL0003", XENON_AP807},
        { .id = "MRVL0004", XENON_CP110},
        {}
};
MODULE_DEVICE_TABLE(acpi, sdhci_xenon_acpi_ids);
#endif

static struct platform_driver sdhci_xenon_driver = {
        .driver = {
                .name   = "xenon-sdhci",
                .probe_type = PROBE_PREFER_ASYNCHRONOUS,
                .of_match_table = sdhci_xenon_dt_ids,
                .acpi_match_table = ACPI_PTR(sdhci_xenon_acpi_ids),
                .pm = &sdhci_xenon_dev_pm_ops,
        },
        .probe  = xenon_probe,
        .remove = xenon_remove,
};

module_platform_driver(sdhci_xenon_driver);

MODULE_DESCRIPTION("SDHCI platform driver for Marvell Xenon SDHC");
MODULE_AUTHOR("Hu Ziji <huziji@marvell.com>");
MODULE_LICENSE("GPL v2");