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 <adrian.hunter@xxxxxxxxx>
---
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 int intel_probe_slot(struct platform_device *pdev, const char *hid,
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 int intel_probe_slot(struct platform_device *pdev, const char *hid,
.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 int intel_probe_slot(struct platform_device *pdev, const char *hid,
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 = {
--
1.9.1
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