mmc: sdhci-pci: Fix 3.3V voltage switch for some BYT-based Intel controllers

Fix 3.3V voltage switch for some BYT-based Intel controllers by making use
of the ACPI DSM.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c
index 9dfbd7f..77dd352 100644 (file)
--- a/drivers/mmc/host/sdhci-pci-core.c
+++ b/drivers/mmc/host/sdhci-pci-core.c
@@ -453,6 +453,7 @@ static const struct sdhci_pci_fixes sdhci_intel_pch_sdio = {
 enum {
        INTEL_DSM_FNS           =  0,
        INTEL_DSM_V18_SWITCH    =  3,
+       INTEL_DSM_V33_SWITCH    =  4,
        INTEL_DSM_DRV_STRENGTH  =  9,
        INTEL_DSM_D3_RETUNE     = 10,
 };
@@ -620,17 +621,37 @@ static void intel_hs400_enhanced_strobe(struct mmc_host *mmc,
        sdhci_writel(host, val, INTEL_HS400_ES_REG);
 }
 
-static void sdhci_intel_voltage_switch(struct sdhci_host *host)
+static int intel_start_signal_voltage_switch(struct mmc_host *mmc,
+                                            struct mmc_ios *ios)
 {
+       struct device *dev = mmc_dev(mmc);
+       struct sdhci_host *host = mmc_priv(mmc);
        struct sdhci_pci_slot *slot = sdhci_priv(host);
        struct intel_host *intel_host = sdhci_pci_priv(slot);
-       struct device *dev = &slot->chip->pdev->dev;
+       unsigned int fn;
        u32 result = 0;
        int err;
 
-       err = intel_dsm(intel_host, dev, INTEL_DSM_V18_SWITCH, &result);
-       pr_debug("%s: %s DSM error %d result %u\n",
-                mmc_hostname(host->mmc), __func__, err, result);
+       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 const struct sdhci_ops sdhci_intel_byt_ops = {
@@ -641,7 +662,6 @@ static const struct sdhci_ops sdhci_intel_byt_ops = {
        .reset                  = sdhci_reset,
        .set_uhs_signaling      = sdhci_set_uhs_signaling,
        .hw_reset               = sdhci_pci_hw_reset,
-       .voltage_switch         = sdhci_intel_voltage_switch,
 };
 
 static const struct sdhci_ops sdhci_intel_glk_ops = {
@@ -652,7 +672,6 @@ static const struct sdhci_ops sdhci_intel_glk_ops = {
        .reset                  = sdhci_reset,
        .set_uhs_signaling      = sdhci_set_uhs_signaling,
        .hw_reset               = sdhci_pci_hw_reset,
-       .voltage_switch         = sdhci_intel_voltage_switch,
        .irq                    = sdhci_cqhci_irq,
 };
 
@@ -691,6 +710,7 @@ static void byt_probe_slot(struct sdhci_pci_slot *slot)
        byt_read_dsm(slot);
 
        ops->execute_tuning = intel_execute_tuning;
+       ops->start_signal_voltage_switch = intel_start_signal_voltage_switch;
 }
 
 static int byt_emmc_probe_slot(struct sdhci_pci_slot *slot)