Commit 1c451c13 authored by Adrian Hunter's avatar Adrian Hunter Committed by Ulf Hansson
Browse files

mmc: sdhci-acpi: Fix voltage switch for some Intel host controllers 



Some Intel host controllers use an ACPI device-specific method to ensure
correct voltage switching. Fix voltage switch for those, by adding a call
to the DSM.

Signed-off-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent f07b7952

drivers/mmc/host/sdhci-acpi.c

+108 −0
Original line number Diff line number Diff line
@@ -96,6 +96,105 @@ static inline bool sdhci_acpi_flag(struct sdhci_acpi_host *c, unsigned int flag) 
	return c->slot && (c->slot->flags & flag);

}



enum {

	INTEL_DSM_FNS		=  0,

	INTEL_DSM_V18_SWITCH	=  3,

	INTEL_DSM_V33_SWITCH	=  4,

};



struct intel_host {

	u32	dsm_fns;

};



static const guid_t intel_dsm_guid =

	GUID_INIT(0xF6C13EA5, 0x65CD, 0x461F,

		  0xAB, 0x7A, 0x29, 0xF7, 0xE8, 0xD5, 0xBD, 0x61);



static int __intel_dsm(struct intel_host *intel_host, struct device *dev,

		       unsigned int fn, u32 *result)

{

	union acpi_object *obj;

	int err = 0;



	obj = acpi_evaluate_dsm(ACPI_HANDLE(dev), &intel_dsm_guid, 0, fn, NULL);

	if (!obj)

		return -EOPNOTSUPP;



	if (obj->type == ACPI_TYPE_INTEGER) {

		*result = obj->integer.value;

	} else if (obj->type == ACPI_TYPE_BUFFER && obj->buffer.length > 0) {

		size_t len = min_t(size_t, obj->buffer.length, 4);



		*result = 0;

		memcpy(result, obj->buffer.pointer, len);

	} else {

		dev_err(dev, "%s DSM fn %u obj->type %d obj->buffer.length %d\n",

			__func__, fn, obj->type, obj->buffer.length);

		err = -EINVAL;

	}



	ACPI_FREE(obj);



	return err;

}



static int intel_dsm(struct intel_host *intel_host, struct device *dev,

		     unsigned int fn, u32 *result)

{

	if (fn > 31 || !(intel_host->dsm_fns & (1 << fn)))

		return -EOPNOTSUPP;



	return __intel_dsm(intel_host, dev, fn, result);

}



static void intel_dsm_init(struct intel_host *intel_host, struct device *dev,

			   struct mmc_host *mmc)

{

	int err;



	err = __intel_dsm(intel_host, dev, INTEL_DSM_FNS, &intel_host->dsm_fns);

	if (err) {

		pr_debug("%s: DSM not supported, error %d\n",

			 mmc_hostname(mmc), err);

		return;

	}



	pr_debug("%s: DSM function mask %#x\n",

		 mmc_hostname(mmc), intel_host->dsm_fns);

}



static int intel_start_signal_voltage_switch(struct mmc_host *mmc,

					     struct mmc_ios *ios)

{

	struct device *dev = mmc_dev(mmc);

	struct sdhci_acpi_host *c = dev_get_drvdata(dev);

	struct intel_host *intel_host = sdhci_acpi_priv(c);

	unsigned int fn;

	u32 result = 0;

	int err;



	err = sdhci_start_signal_voltage_switch(mmc, ios);

	if (err)

		return err;



	switch (ios->signal_voltage) {

	case MMC_SIGNAL_VOLTAGE_330:

		fn = INTEL_DSM_V33_SWITCH;

		break;

	case MMC_SIGNAL_VOLTAGE_180:

		fn = INTEL_DSM_V18_SWITCH;

		break;

	default:

		return 0;

	}



	err = intel_dsm(intel_host, dev, fn, &result);

	pr_debug("%s: %s DSM fn %u error %d result %u\n",

		 mmc_hostname(mmc), __func__, fn, err, result);



	return 0;

}



static void sdhci_acpi_int_hw_reset(struct sdhci_host *host)

{

	u8 reg;
@@ -280,6 +379,7 @@ static int intel_probe_slot(struct platform_device *pdev, const char *hid, 
			    const char *uid)

{

	struct sdhci_acpi_host *c = platform_get_drvdata(pdev);

	struct intel_host *intel_host = sdhci_acpi_priv(c);

	struct sdhci_host *host = c->host;



	if (hid && uid && !strcmp(hid, "80860F14") && !strcmp(uid, "1") &&
@@ -290,6 +390,11 @@ static int intel_probe_slot(struct platform_device *pdev, const char *hid, 
	if (hid && !strcmp(hid, "80865ACA"))

		host->mmc_host_ops.get_cd = bxt_get_cd;



	intel_dsm_init(intel_host, &pdev->dev, host->mmc);



	host->mmc_host_ops.start_signal_voltage_switch =

					intel_start_signal_voltage_switch;



	return 0;

}
@@ -304,6 +409,7 @@ static const struct sdhci_acpi_slot sdhci_acpi_slot_int_emmc = { 
		   SDHCI_QUIRK2_STOP_WITH_TC |

		   SDHCI_QUIRK2_CAPS_BIT63_FOR_HS400,

	.probe_slot	= intel_probe_slot,

	.priv_size	= sizeof(struct intel_host),

};



static const struct sdhci_acpi_slot sdhci_acpi_slot_int_sdio = {
@@ -315,6 +421,7 @@ static const struct sdhci_acpi_slot sdhci_acpi_slot_int_sdio = { 
	.flags   = SDHCI_ACPI_RUNTIME_PM,

	.pm_caps = MMC_PM_KEEP_POWER,

	.probe_slot	= intel_probe_slot,

	.priv_size	= sizeof(struct intel_host),

};



static const struct sdhci_acpi_slot sdhci_acpi_slot_int_sd = {
@@ -325,6 +432,7 @@ static const struct sdhci_acpi_slot sdhci_acpi_slot_int_sd = { 
		   SDHCI_QUIRK2_STOP_WITH_TC,

	.caps    = MMC_CAP_WAIT_WHILE_BUSY | MMC_CAP_AGGRESSIVE_PM,

	.probe_slot	= intel_probe_slot,

	.priv_size	= sizeof(struct intel_host),

};



static const struct sdhci_acpi_slot sdhci_acpi_slot_qcom_sd_3v = {