drivers/mmc/host/sdhci-tegra.c - kernel/msm-4.9 - Gitiles

 /*
  * Copyright (C) 2010 Google, Inc.
  *
  * This software is licensed under the terms of the GNU General Public
  * License version 2, as published by the Free Software Foundation, and
  * may be copied, distributed, and modified under those terms.
  *
  * 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.
  *
  */

 #include <linux/err.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
 #include <linux/clk.h>
 #include <linux/io.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/of_gpio.h>
 #include <linux/gpio.h>
 #include <linux/mmc/card.h>
 #include <linux/mmc/host.h>

 #include <asm/gpio.h>

 #include <mach/gpio-tegra.h>
 #include <mach/sdhci.h>

 #include "sdhci-pltfm.h"

 #define NVQUIRK_FORCE_SDHCI_SPEC_200	BIT(0)
 #define NVQUIRK_ENABLE_BLOCK_GAP_DET	BIT(1)

 struct sdhci_tegra_soc_data {
 	struct sdhci_pltfm_data *pdata;
 	u32 nvquirks;
 };

 struct sdhci_tegra {
 	const struct tegra_sdhci_platform_data *plat;
 	const struct sdhci_tegra_soc_data *soc_data;
 };

 static u32 tegra_sdhci_readl(struct sdhci_host *host, int reg)
 {
 	u32 val;

 	if (unlikely(reg == SDHCI_PRESENT_STATE)) {
 		/* Use wp_gpio here instead? */
 		val = readl(host->ioaddr + reg);
 		return val | SDHCI_WRITE_PROTECT;
 	}

 	return readl(host->ioaddr + reg);
 }

 static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
 {
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;

 	if (unlikely((soc_data->nvquirks & NVQUIRK_FORCE_SDHCI_SPEC_200) &&
 			(reg == SDHCI_HOST_VERSION))) {
 		/* Erratum: Version register is invalid in HW. */
 		return SDHCI_SPEC_200;
 	}

 	return readw(host->ioaddr + reg);
 }

 static void tegra_sdhci_writel(struct sdhci_host *host, u32 val, int reg)
 {
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
 	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;

 	/* Seems like we're getting spurious timeout and crc errors, so
 	 * disable signalling of them. In case of real errors software
 	 * timers should take care of eventually detecting them.
 	 */
 	if (unlikely(reg == SDHCI_SIGNAL_ENABLE))
 		val &= ~(SDHCI_INT_TIMEOUT|SDHCI_INT_CRC);

 	writel(val, host->ioaddr + reg);

 	if (unlikely((soc_data->nvquirks & NVQUIRK_ENABLE_BLOCK_GAP_DET) &&
 			(reg == SDHCI_INT_ENABLE))) {
 		/* Erratum: Must enable block gap interrupt detection */
 		u8 gap_ctrl = readb(host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
 		if (val & SDHCI_INT_CARD_INT)
 			gap_ctrl |= 0x8;
 		else
 			gap_ctrl &= ~0x8;
 		writeb(gap_ctrl, host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
 	}
 }

 static unsigned int tegra_sdhci_get_ro(struct sdhci_host *host)
 {
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
 	const struct tegra_sdhci_platform_data *plat = tegra_host->plat;

 	if (!gpio_is_valid(plat->wp_gpio))
 		return -1;

 	return gpio_get_value(plat->wp_gpio);
 }

 static irqreturn_t carddetect_irq(int irq, void *data)
 {
 	struct sdhci_host *sdhost = (struct sdhci_host *)data;

 	tasklet_schedule(&sdhost->card_tasklet);
 	return IRQ_HANDLED;
 };

 static int tegra_sdhci_8bit(struct sdhci_host *host, int bus_width)
 {
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
 	const struct tegra_sdhci_platform_data *plat = tegra_host->plat;
 	u32 ctrl;

 	ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
 	if (plat->is_8bit && bus_width == MMC_BUS_WIDTH_8) {
 		ctrl &= ~SDHCI_CTRL_4BITBUS;
 		ctrl |= SDHCI_CTRL_8BITBUS;
 	} else {
 		ctrl &= ~SDHCI_CTRL_8BITBUS;
 		if (bus_width == MMC_BUS_WIDTH_4)
 			ctrl |= SDHCI_CTRL_4BITBUS;
 		else
 			ctrl &= ~SDHCI_CTRL_4BITBUS;
 	}
 	sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
 	return 0;
 }

 static struct sdhci_ops tegra_sdhci_ops = {
 	.get_ro     = tegra_sdhci_get_ro,
 	.read_l     = tegra_sdhci_readl,
 	.read_w     = tegra_sdhci_readw,
 	.write_l    = tegra_sdhci_writel,
 	.platform_8bit_width = tegra_sdhci_8bit,
 };

 #ifdef CONFIG_ARCH_TEGRA_2x_SOC
 static struct sdhci_pltfm_data sdhci_tegra20_pdata = {
 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
 		  SDHCI_QUIRK_NO_HISPD_BIT |
 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
 	.ops  = &tegra_sdhci_ops,
 };

 static struct sdhci_tegra_soc_data soc_data_tegra20 = {
 	.pdata = &sdhci_tegra20_pdata,
 	.nvquirks = NVQUIRK_FORCE_SDHCI_SPEC_200 |
 		    NVQUIRK_ENABLE_BLOCK_GAP_DET,
 };
 #endif

 #ifdef CONFIG_ARCH_TEGRA_3x_SOC
 static struct sdhci_pltfm_data sdhci_tegra30_pdata = {
 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
 		  SDHCI_QUIRK_NO_HISPD_BIT |
 		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
 	.ops  = &tegra_sdhci_ops,
 };

 static struct sdhci_tegra_soc_data soc_data_tegra30 = {
 	.pdata = &sdhci_tegra30_pdata,
 };
 #endif

 static const struct of_device_id sdhci_tegra_dt_match[] __devinitdata = {
 #ifdef CONFIG_ARCH_TEGRA_3x_SOC
 	{ .compatible = "nvidia,tegra30-sdhci", .data = &soc_data_tegra30 },
 #endif
 #ifdef CONFIG_ARCH_TEGRA_2x_SOC
 	{ .compatible = "nvidia,tegra20-sdhci", .data = &soc_data_tegra20 },
 #endif
 	{}
 };
 MODULE_DEVICE_TABLE(of, sdhci_dt_ids);

 static struct tegra_sdhci_platform_data * __devinit sdhci_tegra_dt_parse_pdata(
 						struct platform_device *pdev)
 {
 	struct tegra_sdhci_platform_data *plat;
 	struct device_node *np = pdev->dev.of_node;

 	if (!np)
 		return NULL;

 	plat = devm_kzalloc(&pdev->dev, sizeof(*plat), GFP_KERNEL);
 	if (!plat) {
 		dev_err(&pdev->dev, "Can't allocate platform data\n");
 		return NULL;
 	}

 	plat->cd_gpio = of_get_named_gpio(np, "cd-gpios", 0);
 	plat->wp_gpio = of_get_named_gpio(np, "wp-gpios", 0);
 	plat->power_gpio = of_get_named_gpio(np, "power-gpios", 0);
 	if (of_find_property(np, "support-8bit", NULL))
 		plat->is_8bit = 1;

 	return plat;
 }

 static int __devinit sdhci_tegra_probe(struct platform_device *pdev)
 {
 	const struct of_device_id *match;
 	const struct sdhci_tegra_soc_data *soc_data;
 	struct sdhci_host *host;
 	struct sdhci_pltfm_host *pltfm_host;
 	struct tegra_sdhci_platform_data *plat;
 	struct sdhci_tegra *tegra_host;
 	struct clk *clk;
 	int rc;

 	match = of_match_device(sdhci_tegra_dt_match, &pdev->dev);
 	if (match)
 		soc_data = match->data;
 	else
 		soc_data = &soc_data_tegra20;

 	host = sdhci_pltfm_init(pdev, soc_data->pdata);
 	if (IS_ERR(host))
 		return PTR_ERR(host);

 	pltfm_host = sdhci_priv(host);

 	plat = pdev->dev.platform_data;

 	if (plat == NULL)
 		plat = sdhci_tegra_dt_parse_pdata(pdev);

 	if (plat == NULL) {
 		dev_err(mmc_dev(host->mmc), "missing platform data\n");
 		rc = -ENXIO;
 		goto err_no_plat;
 	}

 	tegra_host = devm_kzalloc(&pdev->dev, sizeof(*tegra_host), GFP_KERNEL);
 	if (!tegra_host) {
 		dev_err(mmc_dev(host->mmc), "failed to allocate tegra_host\n");
 		rc = -ENOMEM;
 		goto err_no_plat;
 	}

 	tegra_host->plat = plat;
 	tegra_host->soc_data = soc_data;

 	pltfm_host->priv = tegra_host;

 	if (gpio_is_valid(plat->power_gpio)) {
 		rc = gpio_request(plat->power_gpio, "sdhci_power");
 		if (rc) {
 			dev_err(mmc_dev(host->mmc),
 				"failed to allocate power gpio\n");
 			goto err_power_req;
 		}
 		tegra_gpio_enable(plat->power_gpio);
 		gpio_direction_output(plat->power_gpio, 1);
 	}

 	if (gpio_is_valid(plat->cd_gpio)) {
 		rc = gpio_request(plat->cd_gpio, "sdhci_cd");
 		if (rc) {
 			dev_err(mmc_dev(host->mmc),
 				"failed to allocate cd gpio\n");
 			goto err_cd_req;
 		}
 		tegra_gpio_enable(plat->cd_gpio);
 		gpio_direction_input(plat->cd_gpio);

 		rc = request_irq(gpio_to_irq(plat->cd_gpio), carddetect_irq,
 				 IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
 				 mmc_hostname(host->mmc), host);

 		if (rc)	{
 			dev_err(mmc_dev(host->mmc), "request irq error\n");
 			goto err_cd_irq_req;
 		}

 	}

 	if (gpio_is_valid(plat->wp_gpio)) {
 		rc = gpio_request(plat->wp_gpio, "sdhci_wp");
 		if (rc) {
 			dev_err(mmc_dev(host->mmc),
 				"failed to allocate wp gpio\n");
 			goto err_wp_req;
 		}
 		tegra_gpio_enable(plat->wp_gpio);
 		gpio_direction_input(plat->wp_gpio);
 	}

 	clk = clk_get(mmc_dev(host->mmc), NULL);
 	if (IS_ERR(clk)) {
 		dev_err(mmc_dev(host->mmc), "clk err\n");
 		rc = PTR_ERR(clk);
 		goto err_clk_get;
 	}
 	clk_enable(clk);
 	pltfm_host->clk = clk;

 	host->mmc->pm_caps = plat->pm_flags;

 	if (plat->is_8bit)
 		host->mmc->caps |= MMC_CAP_8_BIT_DATA;

 	rc = sdhci_add_host(host);
 	if (rc)
 		goto err_add_host;

 	return 0;

 err_add_host:
 	clk_disable(pltfm_host->clk);
 	clk_put(pltfm_host->clk);
 err_clk_get:
 	if (gpio_is_valid(plat->wp_gpio)) {
 		tegra_gpio_disable(plat->wp_gpio);
 		gpio_free(plat->wp_gpio);
 	}
 err_wp_req:
 	if (gpio_is_valid(plat->cd_gpio))
 		free_irq(gpio_to_irq(plat->cd_gpio), host);
 err_cd_irq_req:
 	if (gpio_is_valid(plat->cd_gpio)) {
 		tegra_gpio_disable(plat->cd_gpio);
 		gpio_free(plat->cd_gpio);
 	}
 err_cd_req:
 	if (gpio_is_valid(plat->power_gpio)) {
 		tegra_gpio_disable(plat->power_gpio);
 		gpio_free(plat->power_gpio);
 	}
 err_power_req:
 err_no_plat:
 	sdhci_pltfm_free(pdev);
 	return rc;
 }

 static int __devexit sdhci_tegra_remove(struct platform_device *pdev)
 {
 	struct sdhci_host *host = platform_get_drvdata(pdev);
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_tegra *tegra_host = pltfm_host->priv;
 	const struct tegra_sdhci_platform_data *plat = tegra_host->plat;
 	int dead = (readl(host->ioaddr + SDHCI_INT_STATUS) == 0xffffffff);

 	sdhci_remove_host(host, dead);

 	if (gpio_is_valid(plat->wp_gpio)) {
 		tegra_gpio_disable(plat->wp_gpio);
 		gpio_free(plat->wp_gpio);
 	}

 	if (gpio_is_valid(plat->cd_gpio)) {
 		free_irq(gpio_to_irq(plat->cd_gpio), host);
 		tegra_gpio_disable(plat->cd_gpio);
 		gpio_free(plat->cd_gpio);
 	}

 	if (gpio_is_valid(plat->power_gpio)) {
 		tegra_gpio_disable(plat->power_gpio);
 		gpio_free(plat->power_gpio);
 	}

 	clk_disable(pltfm_host->clk);
 	clk_put(pltfm_host->clk);

 	sdhci_pltfm_free(pdev);

 	return 0;
 }

 static struct platform_driver sdhci_tegra_driver = {
 	.driver		= {
 		.name	= "sdhci-tegra",
 		.owner	= THIS_MODULE,
 		.of_match_table = sdhci_tegra_dt_match,
 		.pm	= SDHCI_PLTFM_PMOPS,
 	},
 	.probe		= sdhci_tegra_probe,
 	.remove		= __devexit_p(sdhci_tegra_remove),
 };

 module_platform_driver(sdhci_tegra_driver);

 MODULE_DESCRIPTION("SDHCI driver for Tegra");
 MODULE_AUTHOR("Google, Inc.");
 MODULE_LICENSE("GPL v2");
	/*
	* Copyright (C) 2010 Google, Inc.
	*
	* This software is licensed under the terms of the GNU General Public
	* License version 2, as published by the Free Software Foundation, and
	* may be copied, distributed, and modified under those terms.
	*
	* 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.
	*
	*/

	#include <linux/err.h>
	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/platform_device.h>
	#include <linux/clk.h>
	#include <linux/io.h>
	#include <linux/of.h>
	#include <linux/of_device.h>
	#include <linux/of_gpio.h>
	#include <linux/gpio.h>
	#include <linux/mmc/card.h>
	#include <linux/mmc/host.h>

	#include <asm/gpio.h>

	#include <mach/gpio-tegra.h>
	#include <mach/sdhci.h>

	#include "sdhci-pltfm.h"

	#define NVQUIRK_FORCE_SDHCI_SPEC_200 BIT(0)
	#define NVQUIRK_ENABLE_BLOCK_GAP_DET BIT(1)

	struct sdhci_tegra_soc_data {
	struct sdhci_pltfm_data *pdata;
	u32 nvquirks;
	};

	struct sdhci_tegra {
	const struct tegra_sdhci_platform_data *plat;
	const struct sdhci_tegra_soc_data *soc_data;
	};

	static u32 tegra_sdhci_readl(struct sdhci_host *host, int reg)
	{
	u32 val;

	if (unlikely(reg == SDHCI_PRESENT_STATE)) {
	/* Use wp_gpio here instead? */
	val = readl(host->ioaddr + reg);
	return val \| SDHCI_WRITE_PROTECT;
	}

	return readl(host->ioaddr + reg);
	}

	static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
	{
	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
	struct sdhci_tegra *tegra_host = pltfm_host->priv;
	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;

	if (unlikely((soc_data->nvquirks & NVQUIRK_FORCE_SDHCI_SPEC_200) &&
	(reg == SDHCI_HOST_VERSION))) {
	/* Erratum: Version register is invalid in HW. */
	return SDHCI_SPEC_200;
	}

	return readw(host->ioaddr + reg);
	}

	static void tegra_sdhci_writel(struct sdhci_host *host, u32 val, int reg)
	{
	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
	struct sdhci_tegra *tegra_host = pltfm_host->priv;
	const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;

	/* Seems like we're getting spurious timeout and crc errors, so
	* disable signalling of them. In case of real errors software
	* timers should take care of eventually detecting them.
	*/
	if (unlikely(reg == SDHCI_SIGNAL_ENABLE))
	val &= ~(SDHCI_INT_TIMEOUT\|SDHCI_INT_CRC);

	writel(val, host->ioaddr + reg);

	if (unlikely((soc_data->nvquirks & NVQUIRK_ENABLE_BLOCK_GAP_DET) &&
	(reg == SDHCI_INT_ENABLE))) {
	/* Erratum: Must enable block gap interrupt detection */
	u8 gap_ctrl = readb(host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
	if (val & SDHCI_INT_CARD_INT)
	gap_ctrl \|= 0x8;
	else
	gap_ctrl &= ~0x8;
	writeb(gap_ctrl, host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
	}
	}

	static unsigned int tegra_sdhci_get_ro(struct sdhci_host *host)
	{
	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
	struct sdhci_tegra *tegra_host = pltfm_host->priv;
	const struct tegra_sdhci_platform_data *plat = tegra_host->plat;

	if (!gpio_is_valid(plat->wp_gpio))
	return -1;

	return gpio_get_value(plat->wp_gpio);
	}

	static irqreturn_t carddetect_irq(int irq, void *data)
	{
	struct sdhci_host sdhost = (struct sdhci_host )data;

	tasklet_schedule(&sdhost->card_tasklet);
	return IRQ_HANDLED;
	};

	static int tegra_sdhci_8bit(struct sdhci_host *host, int bus_width)
	{
	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
	struct sdhci_tegra *tegra_host = pltfm_host->priv;
	const struct tegra_sdhci_platform_data *plat = tegra_host->plat;
	u32 ctrl;

	ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
	if (plat->is_8bit && bus_width == MMC_BUS_WIDTH_8) {
	ctrl &= ~SDHCI_CTRL_4BITBUS;
	ctrl \|= SDHCI_CTRL_8BITBUS;
	} else {
	ctrl &= ~SDHCI_CTRL_8BITBUS;
	if (bus_width == MMC_BUS_WIDTH_4)
	ctrl \|= SDHCI_CTRL_4BITBUS;
	else
	ctrl &= ~SDHCI_CTRL_4BITBUS;
	}
	sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
	return 0;
	}

	static struct sdhci_ops tegra_sdhci_ops = {
	.get_ro = tegra_sdhci_get_ro,
	.read_l = tegra_sdhci_readl,
	.read_w = tegra_sdhci_readw,
	.write_l = tegra_sdhci_writel,
	.platform_8bit_width = tegra_sdhci_8bit,
	};

	#ifdef CONFIG_ARCH_TEGRA_2x_SOC
	static struct sdhci_pltfm_data sdhci_tegra20_pdata = {
	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL \|
	SDHCI_QUIRK_SINGLE_POWER_WRITE \|
	SDHCI_QUIRK_NO_HISPD_BIT \|
	SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
	.ops = &tegra_sdhci_ops,
	};

	static struct sdhci_tegra_soc_data soc_data_tegra20 = {
	.pdata = &sdhci_tegra20_pdata,
	.nvquirks = NVQUIRK_FORCE_SDHCI_SPEC_200 \|
	NVQUIRK_ENABLE_BLOCK_GAP_DET,
	};
	#endif

	#ifdef CONFIG_ARCH_TEGRA_3x_SOC
	static struct sdhci_pltfm_data sdhci_tegra30_pdata = {
	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL \|
	SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK \|
	SDHCI_QUIRK_SINGLE_POWER_WRITE \|
	SDHCI_QUIRK_NO_HISPD_BIT \|
	SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
	.ops = &tegra_sdhci_ops,
	};

	static struct sdhci_tegra_soc_data soc_data_tegra30 = {
	.pdata = &sdhci_tegra30_pdata,
	};
	#endif

	static const struct of_device_id sdhci_tegra_dt_match[] __devinitdata = {
	#ifdef CONFIG_ARCH_TEGRA_3x_SOC
	{ .compatible = "nvidia,tegra30-sdhci", .data = &soc_data_tegra30 },
	#endif
	#ifdef CONFIG_ARCH_TEGRA_2x_SOC
	{ .compatible = "nvidia,tegra20-sdhci", .data = &soc_data_tegra20 },
	#endif
	{}
	};
	MODULE_DEVICE_TABLE(of, sdhci_dt_ids);

	static struct tegra_sdhci_platform_data * __devinit sdhci_tegra_dt_parse_pdata(
	struct platform_device *pdev)
	{
	struct tegra_sdhci_platform_data *plat;
	struct device_node *np = pdev->dev.of_node;

	if (!np)
	return NULL;

	plat = devm_kzalloc(&pdev->dev, sizeof(*plat), GFP_KERNEL);
	if (!plat) {
	dev_err(&pdev->dev, "Can't allocate platform data\n");
	return NULL;
	}

	plat->cd_gpio = of_get_named_gpio(np, "cd-gpios", 0);
	plat->wp_gpio = of_get_named_gpio(np, "wp-gpios", 0);
	plat->power_gpio = of_get_named_gpio(np, "power-gpios", 0);
	if (of_find_property(np, "support-8bit", NULL))
	plat->is_8bit = 1;

	return plat;
	}

	static int __devinit sdhci_tegra_probe(struct platform_device *pdev)
	{
	const struct of_device_id *match;
	const struct sdhci_tegra_soc_data *soc_data;
	struct sdhci_host *host;
	struct sdhci_pltfm_host *pltfm_host;
	struct tegra_sdhci_platform_data *plat;
	struct sdhci_tegra *tegra_host;
	struct clk *clk;
	int rc;

	match = of_match_device(sdhci_tegra_dt_match, &pdev->dev);
	if (match)
	soc_data = match->data;
	else
	soc_data = &soc_data_tegra20;

	host = sdhci_pltfm_init(pdev, soc_data->pdata);
	if (IS_ERR(host))
	return PTR_ERR(host);

	pltfm_host = sdhci_priv(host);

	plat = pdev->dev.platform_data;

	if (plat == NULL)
	plat = sdhci_tegra_dt_parse_pdata(pdev);

	if (plat == NULL) {
	dev_err(mmc_dev(host->mmc), "missing platform data\n");
	rc = -ENXIO;
	goto err_no_plat;
	}

	tegra_host = devm_kzalloc(&pdev->dev, sizeof(*tegra_host), GFP_KERNEL);
	if (!tegra_host) {
	dev_err(mmc_dev(host->mmc), "failed to allocate tegra_host\n");
	rc = -ENOMEM;
	goto err_no_plat;
	}

	tegra_host->plat = plat;
	tegra_host->soc_data = soc_data;

	pltfm_host->priv = tegra_host;

	if (gpio_is_valid(plat->power_gpio)) {
	rc = gpio_request(plat->power_gpio, "sdhci_power");
	if (rc) {
	dev_err(mmc_dev(host->mmc),
	"failed to allocate power gpio\n");
	goto err_power_req;
	}
	tegra_gpio_enable(plat->power_gpio);
	gpio_direction_output(plat->power_gpio, 1);
	}

	if (gpio_is_valid(plat->cd_gpio)) {
	rc = gpio_request(plat->cd_gpio, "sdhci_cd");
	if (rc) {
	dev_err(mmc_dev(host->mmc),
	"failed to allocate cd gpio\n");
	goto err_cd_req;
	}
	tegra_gpio_enable(plat->cd_gpio);
	gpio_direction_input(plat->cd_gpio);

	rc = request_irq(gpio_to_irq(plat->cd_gpio), carddetect_irq,
	IRQF_TRIGGER_FALLING \| IRQF_TRIGGER_RISING,
	mmc_hostname(host->mmc), host);

	if (rc) {
	dev_err(mmc_dev(host->mmc), "request irq error\n");
	goto err_cd_irq_req;
	}

	}

	if (gpio_is_valid(plat->wp_gpio)) {
	rc = gpio_request(plat->wp_gpio, "sdhci_wp");
	if (rc) {
	dev_err(mmc_dev(host->mmc),
	"failed to allocate wp gpio\n");
	goto err_wp_req;
	}
	tegra_gpio_enable(plat->wp_gpio);
	gpio_direction_input(plat->wp_gpio);
	}

	clk = clk_get(mmc_dev(host->mmc), NULL);
	if (IS_ERR(clk)) {
	dev_err(mmc_dev(host->mmc), "clk err\n");
	rc = PTR_ERR(clk);
	goto err_clk_get;
	}
	clk_enable(clk);
	pltfm_host->clk = clk;

	host->mmc->pm_caps = plat->pm_flags;

	if (plat->is_8bit)
	host->mmc->caps \|= MMC_CAP_8_BIT_DATA;

	rc = sdhci_add_host(host);
	if (rc)
	goto err_add_host;

	return 0;

	err_add_host:
	clk_disable(pltfm_host->clk);
	clk_put(pltfm_host->clk);
	err_clk_get:
	if (gpio_is_valid(plat->wp_gpio)) {
	tegra_gpio_disable(plat->wp_gpio);
	gpio_free(plat->wp_gpio);
	}
	err_wp_req:
	if (gpio_is_valid(plat->cd_gpio))
	free_irq(gpio_to_irq(plat->cd_gpio), host);
	err_cd_irq_req:
	if (gpio_is_valid(plat->cd_gpio)) {
	tegra_gpio_disable(plat->cd_gpio);
	gpio_free(plat->cd_gpio);
	}
	err_cd_req:
	if (gpio_is_valid(plat->power_gpio)) {
	tegra_gpio_disable(plat->power_gpio);
	gpio_free(plat->power_gpio);
	}
	err_power_req:
	err_no_plat:
	sdhci_pltfm_free(pdev);
	return rc;
	}

	static int __devexit sdhci_tegra_remove(struct platform_device *pdev)
	{
	struct sdhci_host *host = platform_get_drvdata(pdev);
	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
	struct sdhci_tegra *tegra_host = pltfm_host->priv;
	const struct tegra_sdhci_platform_data *plat = tegra_host->plat;
	int dead = (readl(host->ioaddr + SDHCI_INT_STATUS) == 0xffffffff);

	sdhci_remove_host(host, dead);

	if (gpio_is_valid(plat->wp_gpio)) {
	tegra_gpio_disable(plat->wp_gpio);
	gpio_free(plat->wp_gpio);
	}

	if (gpio_is_valid(plat->cd_gpio)) {
	free_irq(gpio_to_irq(plat->cd_gpio), host);
	tegra_gpio_disable(plat->cd_gpio);
	gpio_free(plat->cd_gpio);
	}

	if (gpio_is_valid(plat->power_gpio)) {
	tegra_gpio_disable(plat->power_gpio);
	gpio_free(plat->power_gpio);
	}

	clk_disable(pltfm_host->clk);
	clk_put(pltfm_host->clk);

	sdhci_pltfm_free(pdev);

	return 0;
	}

	static struct platform_driver sdhci_tegra_driver = {
	.driver = {
	.name = "sdhci-tegra",
	.owner = THIS_MODULE,
	.of_match_table = sdhci_tegra_dt_match,
	.pm = SDHCI_PLTFM_PMOPS,
	},
	.probe = sdhci_tegra_probe,
	.remove = __devexit_p(sdhci_tegra_remove),
	};

	module_platform_driver(sdhci_tegra_driver);

	MODULE_DESCRIPTION("SDHCI driver for Tegra");
	MODULE_AUTHOR("Google, Inc.");
	MODULE_LICENSE("GPL v2");