drivers/mmc/host/sdhci-of-at91.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Atmel SDMMC controller driver.
  *
  * Copyright (C) 2015 Atmel,
  *		 2015 Ludovic Desroches <ludovic.desroches@atmel.com>
  */

 #include <linux/bitfield.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
 #include <linux/kernel.h>
 #include <linux/mmc/host.h>
 #include <linux/mmc/slot-gpio.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/pm.h>
 #include <linux/pm_runtime.h>

 #include "sdhci-pltfm.h"

 #define SDMMC_MC1R	0x204
 #define		SDMMC_MC1R_DDR		BIT(3)
 #define		SDMMC_MC1R_FCD		BIT(7)
 #define SDMMC_CACR	0x230
 #define		SDMMC_CACR_CAPWREN	BIT(0)
 #define		SDMMC_CACR_KEY		(0x46 << 8)
 #define SDMMC_CALCR	0x240
 #define		SDMMC_CALCR_EN		BIT(0)
 #define		SDMMC_CALCR_ALWYSON	BIT(4)

 #define SDHCI_AT91_PRESET_COMMON_CONF	0x400 /* drv type B, programmable clock mode */

 struct sdhci_at91_soc_data {
 	const struct sdhci_pltfm_data *pdata;
 	bool baseclk_is_generated_internally;
 	unsigned int divider_for_baseclk;
 };

 struct sdhci_at91_priv {
 	const struct sdhci_at91_soc_data *soc_data;
 	struct clk *hclock;
 	struct clk *gck;
 	struct clk *mainck;
 	bool restore_needed;
 	bool cal_always_on;
 };

 static void sdhci_at91_set_force_card_detect(struct sdhci_host *host)
 {
 	u8 mc1r;

 	mc1r = readb(host->ioaddr + SDMMC_MC1R);
 	mc1r |= SDMMC_MC1R_FCD;
 	writeb(mc1r, host->ioaddr + SDMMC_MC1R);
 }

 static void sdhci_at91_set_clock(struct sdhci_host *host, unsigned int clock)
 {
 	u16 clk;

 	host->mmc->actual_clock = 0;

 	/*
 	 * There is no requirement to disable the internal clock before
 	 * changing the SD clock configuration. Moreover, disabling the
 	 * internal clock, changing the configuration and re-enabling the
 	 * internal clock causes some bugs. It can prevent to get the internal
 	 * clock stable flag ready and an unexpected switch to the base clock
 	 * when using presets.
 	 */
 	clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
 	clk &= SDHCI_CLOCK_INT_EN;
 	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);

 	if (clock == 0)
 		return;

 	clk = sdhci_calc_clk(host, clock, &host->mmc->actual_clock);

 	clk |= SDHCI_CLOCK_INT_EN;
 	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);

 	/* Wait max 20 ms */
 	if (read_poll_timeout(sdhci_readw, clk, (clk & SDHCI_CLOCK_INT_STABLE),
 			      1000, 20000, false, host, SDHCI_CLOCK_CONTROL)) {
 		pr_err("%s: Internal clock never stabilised.\n",
 		       mmc_hostname(host->mmc));
 		return;
 	}

 	clk |= SDHCI_CLOCK_CARD_EN;
 	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
 }

 static void sdhci_at91_set_uhs_signaling(struct sdhci_host *host,
 					 unsigned int timing)
 {
 	if (timing == MMC_TIMING_MMC_DDR52)
 		sdhci_writeb(host, SDMMC_MC1R_DDR, SDMMC_MC1R);
 	sdhci_set_uhs_signaling(host, timing);
 }

 static void sdhci_at91_reset(struct sdhci_host *host, u8 mask)
 {
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
 	unsigned int tmp;

 	sdhci_reset(host, mask);

 	if ((host->mmc->caps & MMC_CAP_NONREMOVABLE)
 	    || mmc_gpio_get_cd(host->mmc) >= 0)
 		sdhci_at91_set_force_card_detect(host);

 	if (priv->cal_always_on && (mask & SDHCI_RESET_ALL)) {
 		u32 calcr = sdhci_readl(host, SDMMC_CALCR);

 		sdhci_writel(host, calcr | SDMMC_CALCR_ALWYSON | SDMMC_CALCR_EN,
 			     SDMMC_CALCR);

 		if (read_poll_timeout(sdhci_readl, tmp, !(tmp & SDMMC_CALCR_EN),
 				      10, 20000, false, host, SDMMC_CALCR))
 			dev_err(mmc_dev(host->mmc), "Failed to calibrate\n");
 	}
 }

 static const struct sdhci_ops sdhci_at91_sama5d2_ops = {
 	.set_clock		= sdhci_at91_set_clock,
 	.set_bus_width		= sdhci_set_bus_width,
 	.reset			= sdhci_at91_reset,
 	.set_uhs_signaling	= sdhci_at91_set_uhs_signaling,
 	.set_power		= sdhci_set_power_and_bus_voltage,
 };

 static const struct sdhci_pltfm_data sdhci_sama5d2_pdata = {
 	.ops = &sdhci_at91_sama5d2_ops,
 };

 static const struct sdhci_at91_soc_data soc_data_sama5d2 = {
 	.pdata = &sdhci_sama5d2_pdata,
 	.baseclk_is_generated_internally = false,
 };

 static const struct sdhci_at91_soc_data soc_data_sam9x60 = {
 	.pdata = &sdhci_sama5d2_pdata,
 	.baseclk_is_generated_internally = true,
 	.divider_for_baseclk = 2,
 };

 static const struct of_device_id sdhci_at91_dt_match[] = {
 	{ .compatible = "atmel,sama5d2-sdhci", .data = &soc_data_sama5d2 },
 	{ .compatible = "microchip,sam9x60-sdhci", .data = &soc_data_sam9x60 },
 	{}
 };
 MODULE_DEVICE_TABLE(of, sdhci_at91_dt_match);

 static int sdhci_at91_set_clks_presets(struct device *dev)
 {
 	struct sdhci_host *host = dev_get_drvdata(dev);
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
 	unsigned int			caps0, caps1;
 	unsigned int			clk_base, clk_mul;
 	unsigned int			gck_rate, clk_base_rate;
 	unsigned int			preset_div;

 	clk_prepare_enable(priv->hclock);
 	caps0 = readl(host->ioaddr + SDHCI_CAPABILITIES);
 	caps1 = readl(host->ioaddr + SDHCI_CAPABILITIES_1);

 	gck_rate = clk_get_rate(priv->gck);
 	if (priv->soc_data->baseclk_is_generated_internally)
 		clk_base_rate = gck_rate / priv->soc_data->divider_for_baseclk;
 	else
 		clk_base_rate = clk_get_rate(priv->mainck);

 	clk_base = clk_base_rate / 1000000;
 	clk_mul = gck_rate / clk_base_rate - 1;

 	caps0 &= ~SDHCI_CLOCK_V3_BASE_MASK;
 	caps0 |= FIELD_PREP(SDHCI_CLOCK_V3_BASE_MASK, clk_base);
 	caps1 &= ~SDHCI_CLOCK_MUL_MASK;
 	caps1 |= FIELD_PREP(SDHCI_CLOCK_MUL_MASK, clk_mul);
 	/* Set capabilities in r/w mode. */
 	writel(SDMMC_CACR_KEY | SDMMC_CACR_CAPWREN, host->ioaddr + SDMMC_CACR);
 	writel(caps0, host->ioaddr + SDHCI_CAPABILITIES);
 	writel(caps1, host->ioaddr + SDHCI_CAPABILITIES_1);
 	/* Set capabilities in ro mode. */
 	writel(0, host->ioaddr + SDMMC_CACR);

 	dev_dbg(dev, "update clk mul to %u as gck rate is %u Hz and clk base is %u Hz\n",
 		clk_mul, gck_rate, clk_base_rate);

 	/*
 	 * We have to set preset values because it depends on the clk_mul
 	 * value. Moreover, SDR104 is supported in a degraded mode since the
 	 * maximum sd clock value is 120 MHz instead of 208 MHz. For that
 	 * reason, we need to use presets to support SDR104.
 	 */
 	preset_div = DIV_ROUND_UP(gck_rate, 24000000) - 1;
 	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
 	       host->ioaddr + SDHCI_PRESET_FOR_SDR12);
 	preset_div = DIV_ROUND_UP(gck_rate, 50000000) - 1;
 	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
 	       host->ioaddr + SDHCI_PRESET_FOR_SDR25);
 	preset_div = DIV_ROUND_UP(gck_rate, 100000000) - 1;
 	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
 	       host->ioaddr + SDHCI_PRESET_FOR_SDR50);
 	preset_div = DIV_ROUND_UP(gck_rate, 120000000) - 1;
 	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
 	       host->ioaddr + SDHCI_PRESET_FOR_SDR104);
 	preset_div = DIV_ROUND_UP(gck_rate, 50000000) - 1;
 	writew(SDHCI_AT91_PRESET_COMMON_CONF | preset_div,
 	       host->ioaddr + SDHCI_PRESET_FOR_DDR50);

 	clk_prepare_enable(priv->mainck);
 	clk_prepare_enable(priv->gck);

 	return 0;
 }

 #ifdef CONFIG_PM_SLEEP
 static int sdhci_at91_suspend(struct device *dev)
 {
 	struct sdhci_host *host = dev_get_drvdata(dev);
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
 	int ret;

 	ret = pm_runtime_force_suspend(dev);

 	priv->restore_needed = true;

 	return ret;
 }
 #endif /* CONFIG_PM_SLEEP */

 #ifdef CONFIG_PM
 static int sdhci_at91_runtime_suspend(struct device *dev)
 {
 	struct sdhci_host *host = dev_get_drvdata(dev);
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
 	int ret;

 	ret = sdhci_runtime_suspend_host(host);

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

 	clk_disable_unprepare(priv->gck);
 	clk_disable_unprepare(priv->hclock);
 	clk_disable_unprepare(priv->mainck);

 	return ret;
 }

 static int sdhci_at91_runtime_resume(struct device *dev)
 {
 	struct sdhci_host *host = dev_get_drvdata(dev);
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
 	int ret;

 	if (priv->restore_needed) {
 		ret = sdhci_at91_set_clks_presets(dev);
 		if (ret)
 			return ret;

 		priv->restore_needed = false;
 		goto out;
 	}

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

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

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

 out:
 	return sdhci_runtime_resume_host(host, 0);
 }
 #endif /* CONFIG_PM */

 static const struct dev_pm_ops sdhci_at91_dev_pm_ops = {
 	SET_SYSTEM_SLEEP_PM_OPS(sdhci_at91_suspend, pm_runtime_force_resume)
 	SET_RUNTIME_PM_OPS(sdhci_at91_runtime_suspend,
 			   sdhci_at91_runtime_resume,
 			   NULL)
 };

 static int sdhci_at91_probe(struct platform_device *pdev)
 {
 	const struct of_device_id	*match;
 	const struct sdhci_at91_soc_data	*soc_data;
 	struct sdhci_host		*host;
 	struct sdhci_pltfm_host		*pltfm_host;
 	struct sdhci_at91_priv		*priv;
 	int				ret;

 	match = of_match_device(sdhci_at91_dt_match, &pdev->dev);
 	if (!match)
 		return -EINVAL;
 	soc_data = match->data;

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

 	pltfm_host = sdhci_priv(host);
 	priv = sdhci_pltfm_priv(pltfm_host);
 	priv->soc_data = soc_data;

 	priv->mainck = devm_clk_get(&pdev->dev, "baseclk");
 	if (IS_ERR(priv->mainck)) {
 		if (soc_data->baseclk_is_generated_internally) {
 			priv->mainck = NULL;
 		} else {
 			dev_err(&pdev->dev, "failed to get baseclk\n");
 			ret = PTR_ERR(priv->mainck);
 			goto sdhci_pltfm_free;
 		}
 	}

 	priv->hclock = devm_clk_get(&pdev->dev, "hclock");
 	if (IS_ERR(priv->hclock)) {
 		dev_err(&pdev->dev, "failed to get hclock\n");
 		ret = PTR_ERR(priv->hclock);
 		goto sdhci_pltfm_free;
 	}

 	priv->gck = devm_clk_get(&pdev->dev, "multclk");
 	if (IS_ERR(priv->gck)) {
 		dev_err(&pdev->dev, "failed to get multclk\n");
 		ret = PTR_ERR(priv->gck);
 		goto sdhci_pltfm_free;
 	}

 	ret = sdhci_at91_set_clks_presets(&pdev->dev);
 	if (ret)
 		goto sdhci_pltfm_free;

 	priv->restore_needed = false;

 	/*
 	 * if SDCAL pin is wrongly connected, we must enable
 	 * the analog calibration cell permanently.
 	 */
 	priv->cal_always_on =
 		device_property_read_bool(&pdev->dev,
 					  "microchip,sdcal-inverted");

 	ret = mmc_of_parse(host->mmc);
 	if (ret)
 		goto clocks_disable_unprepare;

 	sdhci_get_of_property(pdev);

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

 	/* HS200 is broken at this moment */
 	host->quirks2 |= SDHCI_QUIRK2_BROKEN_HS200;

 	ret = sdhci_add_host(host);
 	if (ret)
 		goto pm_runtime_disable;

 	/*
 	 * When calling sdhci_runtime_suspend_host(), the sdhci layer makes
 	 * the assumption that all the clocks of the controller are disabled.
 	 * It means we can't get irq from it when it is runtime suspended.
 	 * For that reason, it is not planned to wake-up on a card detect irq
 	 * from the controller.
 	 * If we want to use runtime PM and to be able to wake-up on card
 	 * insertion, we have to use a GPIO for the card detection or we can
 	 * use polling. Be aware that using polling will resume/suspend the
 	 * controller between each attempt.
 	 * Disable SDHCI_QUIRK_BROKEN_CARD_DETECTION to be sure nobody tries
 	 * to enable polling via device tree with broken-cd property.
 	 */
 	if (mmc_card_is_removable(host->mmc) &&
 	    mmc_gpio_get_cd(host->mmc) < 0) {
 		host->mmc->caps |= MMC_CAP_NEEDS_POLL;
 		host->quirks &= ~SDHCI_QUIRK_BROKEN_CARD_DETECTION;
 	}

 	/*
 	 * If the device attached to the MMC bus is not removable, it is safer
 	 * to set the Force Card Detect bit. People often don't connect the
 	 * card detect signal and use this pin for another purpose. If the card
 	 * detect pin is not muxed to SDHCI controller, a default value is
 	 * used. This value can be different from a SoC revision to another
 	 * one. Problems come when this default value is not card present. To
 	 * avoid this case, if the device is non removable then the card
 	 * detection procedure using the SDMCC_CD signal is bypassed.
 	 * This bit is reset when a software reset for all command is performed
 	 * so we need to implement our own reset function to set back this bit.
 	 *
 	 * WA: SAMA5D2 doesn't drive CMD if using CD GPIO line.
 	 */
 	if ((host->mmc->caps & MMC_CAP_NONREMOVABLE)
 	    || mmc_gpio_get_cd(host->mmc) >= 0)
 		sdhci_at91_set_force_card_detect(host);

 	pm_runtime_put_autosuspend(&pdev->dev);

 	return 0;

 pm_runtime_disable:
 	pm_runtime_disable(&pdev->dev);
 	pm_runtime_set_suspended(&pdev->dev);
 	pm_runtime_put_noidle(&pdev->dev);
 clocks_disable_unprepare:
 	clk_disable_unprepare(priv->gck);
 	clk_disable_unprepare(priv->mainck);
 	clk_disable_unprepare(priv->hclock);
 sdhci_pltfm_free:
 	sdhci_pltfm_free(pdev);
 	return ret;
 }

 static int sdhci_at91_remove(struct platform_device *pdev)
 {
 	struct sdhci_host	*host = platform_get_drvdata(pdev);
 	struct sdhci_pltfm_host	*pltfm_host = sdhci_priv(host);
 	struct sdhci_at91_priv	*priv = sdhci_pltfm_priv(pltfm_host);
 	struct clk *gck = priv->gck;
 	struct clk *hclock = priv->hclock;
 	struct clk *mainck = priv->mainck;

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

 	sdhci_pltfm_unregister(pdev);

 	clk_disable_unprepare(gck);
 	clk_disable_unprepare(hclock);
 	clk_disable_unprepare(mainck);

 	return 0;
 }

 static struct platform_driver sdhci_at91_driver = {
 	.driver		= {
 		.name	= "sdhci-at91",
 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
 		.of_match_table = sdhci_at91_dt_match,
 		.pm	= &sdhci_at91_dev_pm_ops,
 	},
 	.probe		= sdhci_at91_probe,
 	.remove		= sdhci_at91_remove,
 };

 module_platform_driver(sdhci_at91_driver);

 MODULE_DESCRIPTION("SDHCI driver for at91");
 MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@atmel.com>");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* Atmel SDMMC controller driver.
	*
	* Copyright (C) 2015 Atmel,
	* 2015 Ludovic Desroches <ludovic.desroches@atmel.com>
	*/

	#include <linux/bitfield.h>
	#include <linux/clk.h>
	#include <linux/delay.h>
	#include <linux/err.h>
	#include <linux/io.h>
	#include <linux/iopoll.h>
	#include <linux/kernel.h>
	#include <linux/mmc/host.h>
	#include <linux/mmc/slot-gpio.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/of_device.h>
	#include <linux/pm.h>
	#include <linux/pm_runtime.h>

	#include "sdhci-pltfm.h"

	#define SDMMC_MC1R 0x204
	#define SDMMC_MC1R_DDR BIT(3)
	#define SDMMC_MC1R_FCD BIT(7)
	#define SDMMC_CACR 0x230
	#define SDMMC_CACR_CAPWREN BIT(0)
	#define SDMMC_CACR_KEY (0x46 << 8)
	#define SDMMC_CALCR 0x240
	#define SDMMC_CALCR_EN BIT(0)
	#define SDMMC_CALCR_ALWYSON BIT(4)

	#define SDHCI_AT91_PRESET_COMMON_CONF 0x400 /* drv type B, programmable clock mode */

	struct sdhci_at91_soc_data {
	const struct sdhci_pltfm_data *pdata;
	bool baseclk_is_generated_internally;
	unsigned int divider_for_baseclk;
	};

	struct sdhci_at91_priv {
	const struct sdhci_at91_soc_data *soc_data;
	struct clk *hclock;
	struct clk *gck;
	struct clk *mainck;
	bool restore_needed;
	bool cal_always_on;
	};

	static void sdhci_at91_set_force_card_detect(struct sdhci_host *host)
	{
	u8 mc1r;

	mc1r = readb(host->ioaddr + SDMMC_MC1R);
	mc1r \|= SDMMC_MC1R_FCD;
	writeb(mc1r, host->ioaddr + SDMMC_MC1R);
	}

	static void sdhci_at91_set_clock(struct sdhci_host *host, unsigned int clock)
	{
	u16 clk;

	host->mmc->actual_clock = 0;

	/*
	* There is no requirement to disable the internal clock before
	* changing the SD clock configuration. Moreover, disabling the
	* internal clock, changing the configuration and re-enabling the
	* internal clock causes some bugs. It can prevent to get the internal
	* clock stable flag ready and an unexpected switch to the base clock
	* when using presets.
	*/
	clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
	clk &= SDHCI_CLOCK_INT_EN;
	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);

	if (clock == 0)
	return;

	clk = sdhci_calc_clk(host, clock, &host->mmc->actual_clock);

	clk \|= SDHCI_CLOCK_INT_EN;
	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);

	/* Wait max 20 ms */
	if (read_poll_timeout(sdhci_readw, clk, (clk & SDHCI_CLOCK_INT_STABLE),
	1000, 20000, false, host, SDHCI_CLOCK_CONTROL)) {
	pr_err("%s: Internal clock never stabilised.\n",
	mmc_hostname(host->mmc));
	return;
	}

	clk \|= SDHCI_CLOCK_CARD_EN;
	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
	}

	static void sdhci_at91_set_uhs_signaling(struct sdhci_host *host,
	unsigned int timing)
	{
	if (timing == MMC_TIMING_MMC_DDR52)
	sdhci_writeb(host, SDMMC_MC1R_DDR, SDMMC_MC1R);
	sdhci_set_uhs_signaling(host, timing);
	}

	static void sdhci_at91_reset(struct sdhci_host *host, u8 mask)
	{
	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
	unsigned int tmp;

	sdhci_reset(host, mask);

	if ((host->mmc->caps & MMC_CAP_NONREMOVABLE)
	\|\| mmc_gpio_get_cd(host->mmc) >= 0)
	sdhci_at91_set_force_card_detect(host);

	if (priv->cal_always_on && (mask & SDHCI_RESET_ALL)) {
	u32 calcr = sdhci_readl(host, SDMMC_CALCR);

	sdhci_writel(host, calcr \| SDMMC_CALCR_ALWYSON \| SDMMC_CALCR_EN,
	SDMMC_CALCR);

	if (read_poll_timeout(sdhci_readl, tmp, !(tmp & SDMMC_CALCR_EN),
	10, 20000, false, host, SDMMC_CALCR))
	dev_err(mmc_dev(host->mmc), "Failed to calibrate\n");
	}
	}

	static const struct sdhci_ops sdhci_at91_sama5d2_ops = {
	.set_clock = sdhci_at91_set_clock,
	.set_bus_width = sdhci_set_bus_width,
	.reset = sdhci_at91_reset,
	.set_uhs_signaling = sdhci_at91_set_uhs_signaling,
	.set_power = sdhci_set_power_and_bus_voltage,
	};

	static const struct sdhci_pltfm_data sdhci_sama5d2_pdata = {
	.ops = &sdhci_at91_sama5d2_ops,
	};

	static const struct sdhci_at91_soc_data soc_data_sama5d2 = {
	.pdata = &sdhci_sama5d2_pdata,
	.baseclk_is_generated_internally = false,
	};

	static const struct sdhci_at91_soc_data soc_data_sam9x60 = {
	.pdata = &sdhci_sama5d2_pdata,
	.baseclk_is_generated_internally = true,
	.divider_for_baseclk = 2,
	};

	static const struct of_device_id sdhci_at91_dt_match[] = {
	{ .compatible = "atmel,sama5d2-sdhci", .data = &soc_data_sama5d2 },
	{ .compatible = "microchip,sam9x60-sdhci", .data = &soc_data_sam9x60 },
	{}
	};
	MODULE_DEVICE_TABLE(of, sdhci_at91_dt_match);

	static int sdhci_at91_set_clks_presets(struct device *dev)
	{
	struct sdhci_host *host = dev_get_drvdata(dev);
	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
	unsigned int caps0, caps1;
	unsigned int clk_base, clk_mul;
	unsigned int gck_rate, clk_base_rate;
	unsigned int preset_div;

	clk_prepare_enable(priv->hclock);
	caps0 = readl(host->ioaddr + SDHCI_CAPABILITIES);
	caps1 = readl(host->ioaddr + SDHCI_CAPABILITIES_1);

	gck_rate = clk_get_rate(priv->gck);
	if (priv->soc_data->baseclk_is_generated_internally)
	clk_base_rate = gck_rate / priv->soc_data->divider_for_baseclk;
	else
	clk_base_rate = clk_get_rate(priv->mainck);

	clk_base = clk_base_rate / 1000000;
	clk_mul = gck_rate / clk_base_rate - 1;

	caps0 &= ~SDHCI_CLOCK_V3_BASE_MASK;
	caps0 \|= FIELD_PREP(SDHCI_CLOCK_V3_BASE_MASK, clk_base);
	caps1 &= ~SDHCI_CLOCK_MUL_MASK;
	caps1 \|= FIELD_PREP(SDHCI_CLOCK_MUL_MASK, clk_mul);
	/* Set capabilities in r/w mode. */
	writel(SDMMC_CACR_KEY \| SDMMC_CACR_CAPWREN, host->ioaddr + SDMMC_CACR);
	writel(caps0, host->ioaddr + SDHCI_CAPABILITIES);
	writel(caps1, host->ioaddr + SDHCI_CAPABILITIES_1);
	/* Set capabilities in ro mode. */
	writel(0, host->ioaddr + SDMMC_CACR);

	dev_dbg(dev, "update clk mul to %u as gck rate is %u Hz and clk base is %u Hz\n",
	clk_mul, gck_rate, clk_base_rate);

	/*
	* We have to set preset values because it depends on the clk_mul
	* value. Moreover, SDR104 is supported in a degraded mode since the
	* maximum sd clock value is 120 MHz instead of 208 MHz. For that
	* reason, we need to use presets to support SDR104.
	*/
	preset_div = DIV_ROUND_UP(gck_rate, 24000000) - 1;
	writew(SDHCI_AT91_PRESET_COMMON_CONF \| preset_div,
	host->ioaddr + SDHCI_PRESET_FOR_SDR12);
	preset_div = DIV_ROUND_UP(gck_rate, 50000000) - 1;
	writew(SDHCI_AT91_PRESET_COMMON_CONF \| preset_div,
	host->ioaddr + SDHCI_PRESET_FOR_SDR25);
	preset_div = DIV_ROUND_UP(gck_rate, 100000000) - 1;
	writew(SDHCI_AT91_PRESET_COMMON_CONF \| preset_div,
	host->ioaddr + SDHCI_PRESET_FOR_SDR50);
	preset_div = DIV_ROUND_UP(gck_rate, 120000000) - 1;
	writew(SDHCI_AT91_PRESET_COMMON_CONF \| preset_div,
	host->ioaddr + SDHCI_PRESET_FOR_SDR104);
	preset_div = DIV_ROUND_UP(gck_rate, 50000000) - 1;
	writew(SDHCI_AT91_PRESET_COMMON_CONF \| preset_div,
	host->ioaddr + SDHCI_PRESET_FOR_DDR50);

	clk_prepare_enable(priv->mainck);
	clk_prepare_enable(priv->gck);

	return 0;
	}

	#ifdef CONFIG_PM_SLEEP
	static int sdhci_at91_suspend(struct device *dev)
	{
	struct sdhci_host *host = dev_get_drvdata(dev);
	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
	int ret;

	ret = pm_runtime_force_suspend(dev);

	priv->restore_needed = true;

	return ret;
	}
	#endif /* CONFIG_PM_SLEEP */

	#ifdef CONFIG_PM
	static int sdhci_at91_runtime_suspend(struct device *dev)
	{
	struct sdhci_host *host = dev_get_drvdata(dev);
	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
	int ret;

	ret = sdhci_runtime_suspend_host(host);

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

	clk_disable_unprepare(priv->gck);
	clk_disable_unprepare(priv->hclock);
	clk_disable_unprepare(priv->mainck);

	return ret;
	}

	static int sdhci_at91_runtime_resume(struct device *dev)
	{
	struct sdhci_host *host = dev_get_drvdata(dev);
	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
	int ret;

	if (priv->restore_needed) {
	ret = sdhci_at91_set_clks_presets(dev);
	if (ret)
	return ret;

	priv->restore_needed = false;
	goto out;
	}

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

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

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

	out:
	return sdhci_runtime_resume_host(host, 0);
	}
	#endif /* CONFIG_PM */

	static const struct dev_pm_ops sdhci_at91_dev_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(sdhci_at91_suspend, pm_runtime_force_resume)
	SET_RUNTIME_PM_OPS(sdhci_at91_runtime_suspend,
	sdhci_at91_runtime_resume,
	NULL)
	};

	static int sdhci_at91_probe(struct platform_device *pdev)
	{
	const struct of_device_id *match;
	const struct sdhci_at91_soc_data *soc_data;
	struct sdhci_host *host;
	struct sdhci_pltfm_host *pltfm_host;
	struct sdhci_at91_priv *priv;
	int ret;

	match = of_match_device(sdhci_at91_dt_match, &pdev->dev);
	if (!match)
	return -EINVAL;
	soc_data = match->data;

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

	pltfm_host = sdhci_priv(host);
	priv = sdhci_pltfm_priv(pltfm_host);
	priv->soc_data = soc_data;

	priv->mainck = devm_clk_get(&pdev->dev, "baseclk");
	if (IS_ERR(priv->mainck)) {
	if (soc_data->baseclk_is_generated_internally) {
	priv->mainck = NULL;
	} else {
	dev_err(&pdev->dev, "failed to get baseclk\n");
	ret = PTR_ERR(priv->mainck);
	goto sdhci_pltfm_free;
	}
	}

	priv->hclock = devm_clk_get(&pdev->dev, "hclock");
	if (IS_ERR(priv->hclock)) {
	dev_err(&pdev->dev, "failed to get hclock\n");
	ret = PTR_ERR(priv->hclock);
	goto sdhci_pltfm_free;
	}

	priv->gck = devm_clk_get(&pdev->dev, "multclk");
	if (IS_ERR(priv->gck)) {
	dev_err(&pdev->dev, "failed to get multclk\n");
	ret = PTR_ERR(priv->gck);
	goto sdhci_pltfm_free;
	}

	ret = sdhci_at91_set_clks_presets(&pdev->dev);
	if (ret)
	goto sdhci_pltfm_free;

	priv->restore_needed = false;

	/*
	* if SDCAL pin is wrongly connected, we must enable
	* the analog calibration cell permanently.
	*/
	priv->cal_always_on =
	device_property_read_bool(&pdev->dev,
	"microchip,sdcal-inverted");

	ret = mmc_of_parse(host->mmc);
	if (ret)
	goto clocks_disable_unprepare;

	sdhci_get_of_property(pdev);

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

	/* HS200 is broken at this moment */
	host->quirks2 \|= SDHCI_QUIRK2_BROKEN_HS200;

	ret = sdhci_add_host(host);
	if (ret)
	goto pm_runtime_disable;

	/*
	* When calling sdhci_runtime_suspend_host(), the sdhci layer makes
	* the assumption that all the clocks of the controller are disabled.
	* It means we can't get irq from it when it is runtime suspended.
	* For that reason, it is not planned to wake-up on a card detect irq
	* from the controller.
	* If we want to use runtime PM and to be able to wake-up on card
	* insertion, we have to use a GPIO for the card detection or we can
	* use polling. Be aware that using polling will resume/suspend the
	* controller between each attempt.
	* Disable SDHCI_QUIRK_BROKEN_CARD_DETECTION to be sure nobody tries
	* to enable polling via device tree with broken-cd property.
	*/
	if (mmc_card_is_removable(host->mmc) &&
	mmc_gpio_get_cd(host->mmc) < 0) {
	host->mmc->caps \|= MMC_CAP_NEEDS_POLL;
	host->quirks &= ~SDHCI_QUIRK_BROKEN_CARD_DETECTION;
	}

	/*
	* If the device attached to the MMC bus is not removable, it is safer
	* to set the Force Card Detect bit. People often don't connect the
	* card detect signal and use this pin for another purpose. If the card
	* detect pin is not muxed to SDHCI controller, a default value is
	* used. This value can be different from a SoC revision to another
	* one. Problems come when this default value is not card present. To
	* avoid this case, if the device is non removable then the card
	* detection procedure using the SDMCC_CD signal is bypassed.
	* This bit is reset when a software reset for all command is performed
	* so we need to implement our own reset function to set back this bit.
	*
	* WA: SAMA5D2 doesn't drive CMD if using CD GPIO line.
	*/
	if ((host->mmc->caps & MMC_CAP_NONREMOVABLE)
	\|\| mmc_gpio_get_cd(host->mmc) >= 0)
	sdhci_at91_set_force_card_detect(host);

	pm_runtime_put_autosuspend(&pdev->dev);

	return 0;

	pm_runtime_disable:
	pm_runtime_disable(&pdev->dev);
	pm_runtime_set_suspended(&pdev->dev);
	pm_runtime_put_noidle(&pdev->dev);
	clocks_disable_unprepare:
	clk_disable_unprepare(priv->gck);
	clk_disable_unprepare(priv->mainck);
	clk_disable_unprepare(priv->hclock);
	sdhci_pltfm_free:
	sdhci_pltfm_free(pdev);
	return ret;
	}

	static int sdhci_at91_remove(struct platform_device *pdev)
	{
	struct sdhci_host *host = platform_get_drvdata(pdev);
	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
	struct clk *gck = priv->gck;
	struct clk *hclock = priv->hclock;
	struct clk *mainck = priv->mainck;

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

	sdhci_pltfm_unregister(pdev);

	clk_disable_unprepare(gck);
	clk_disable_unprepare(hclock);
	clk_disable_unprepare(mainck);

	return 0;
	}

	static struct platform_driver sdhci_at91_driver = {
	.driver = {
	.name = "sdhci-at91",
	.probe_type = PROBE_PREFER_ASYNCHRONOUS,
	.of_match_table = sdhci_at91_dt_match,
	.pm = &sdhci_at91_dev_pm_ops,
	},
	.probe = sdhci_at91_probe,
	.remove = sdhci_at91_remove,
	};

	module_platform_driver(sdhci_at91_driver);

	MODULE_DESCRIPTION("SDHCI driver for at91");
	MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@atmel.com>");
	MODULE_LICENSE("GPL v2");