iio: imu: inv_mpu6050: test whoami first and against all known values

[mirror_ubuntu-artful-kernel.git] / drivers / mmc / host / sdhci-xenon.c

/*
 * 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
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation version 2.
 *
 * Inspired by Jisheng Zhang <jszhang@marvell.com>
 * Special thanks to Video BG4 project team.
 */

#include <linux/delay.h>
#include <linux/ktime.h>
#include <linux/module.h>
#include <linux/of.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 (!((reg = sdhci_readw(host, SDHCI_CLOCK_CONTROL))
                        & SDHCI_CLOCK_INT_STABLE)) {
                if (ktime_after(ktime_get(), timeout)) {
                        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);

        xenon_set_acg(host, true);

        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 const struct sdhci_ops sdhci_xenon_ops = {
        .set_clock              = sdhci_set_clock,
        .set_bus_width          = sdhci_set_bus_width,
        .reset                  = xenon_reset,
        .set_uhs_signaling      = xenon_set_uhs_signaling,
        .get_max_clock          = sdhci_pltfm_clk_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)
                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_dt(struct platform_device *pdev)
{
        struct device_node *np = pdev->dev.of_node;
        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;

        /* Disable HS200 on Armada AP806 */
        if (of_device_is_compatible(np, "marvell,armada-ap806-sdhci"))
                host->quirks2 |= SDHCI_QUIRK2_BROKEN_HS200;

        sdhc_id = 0x0;
        if (!of_property_read_u32(np, "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 (!of_property_read_u32(np, "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;

        return xenon_phy_parse_dt(np, 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 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);

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

        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;

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

        sdhci_get_of_property(pdev);

        xenon_set_acg(host, false);

        /* Xenon specific dt parse */
        err = xenon_probe_dt(pdev);
        if (err)
                goto err_clk;

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

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

        return 0;

remove_sdhc:
        xenon_sdhc_unprepare(host);
clean_phy_param:
        xenon_clean_phy(host);
err_clk:
        clk_disable_unprepare(pltfm_host->clk);
free_pltfm:
        sdhci_pltfm_free(pdev);
        return err;
}

static int xenon_remove(struct platform_device *pdev)
{
        struct sdhci_host *host = platform_get_drvdata(pdev);
        struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);

        xenon_clean_phy(host);

        sdhci_remove_host(host, 0);

        xenon_sdhc_unprepare(host);

        clk_disable_unprepare(pltfm_host->clk);

        sdhci_pltfm_free(pdev);

        return 0;
}

static const struct of_device_id sdhci_xenon_dt_ids[] = {
        { .compatible = "marvell,armada-ap806-sdhci",},
        { .compatible = "marvell,armada-cp110-sdhci",},
        { .compatible = "marvell,armada-3700-sdhci",},
        {}
};
MODULE_DEVICE_TABLE(of, sdhci_xenon_dt_ids);

static struct platform_driver sdhci_xenon_driver = {
        .driver = {
                .name   = "xenon-sdhci",
                .of_match_table = sdhci_xenon_dt_ids,
                .pm = &sdhci_pltfm_pmops,
        },
        .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");