From 1c451c139ee4cca63b293eb30eb4e38ab7ca05af Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Thu, 19 Oct 2017 13:41:46 +0300 Subject: [PATCH] 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: Adrian Hunter Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci-acpi.c | 108 ++++++++++++++++++++++++++++++++++ 1 file changed, 108 insertions(+) diff --git a/drivers/mmc/host/sdhci-acpi.c b/drivers/mmc/host/sdhci-acpi.c index 5bb5880403b2..b988997a1e80 100644 --- a/drivers/mmc/host/sdhci-acpi.c +++ b/drivers/mmc/host/sdhci-acpi.c @@ -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 = {