2 files changed, 20 insertions, 3 deletions

diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
index c2d13d7e9911..175a9427b9ba 100644
--- a/drivers/mmc/sdhci.c
+++ b/drivers/mmc/sdhci.c
@@ -37,6 +37,7 @@ static unsigned int debug_quirks = 0;
 #define SDHCI_QUIRK_FORCE_DMA                           (1<<1)
 /* Controller doesn't like some resets when there is no card inserted. */
 #define SDHCI_QUIRK_NO_CARD_NO_RESET                    (1<<2)
+#define SDHCI_QUIRK_SINGLE_POWER_WRITE                  (1<<3)
 
 static const struct pci_device_id pci_ids[] __devinitdata = {
         {
@@ -65,6 +66,14 @@ static const struct pci_device_id pci_ids[] __devinitdata = {
                 .driver_data    = SDHCI_QUIRK_FORCE_DMA,
         },
 
+        {
+                .vendor         = PCI_VENDOR_ID_ENE,
+                .device         = PCI_DEVICE_ID_ENE_CB712_SD,
+                .subvendor      = PCI_ANY_ID,
+                .subdevice      = PCI_ANY_ID,
+                .driver_data    = SDHCI_QUIRK_SINGLE_POWER_WRITE,
+        },
+
         {       /* Generic SD host controller */
                 PCI_DEVICE_CLASS((PCI_CLASS_SYSTEM_SDHCI << 8), 0xFFFF00)
         },
@@ -674,10 +683,17 @@ static void sdhci_set_power(struct sdhci_host *host, unsigned short power)
         if (host->power == power)
                 return;
 
-        writeb(0, host->ioaddr + SDHCI_POWER_CONTROL);
-
-        if (power == (unsigned short)-1)
+        if (power == (unsigned short)-1) {
+                writeb(0, host->ioaddr + SDHCI_POWER_CONTROL);
                 goto out;
+        }
+
+        /*
+         * Spec says that we should clear the power reg before setting
+         * a new value. Some controllers don't seem to like this though.
+         */
+        if (!(host->chip->quirks & SDHCI_QUIRK_SINGLE_POWER_WRITE))
+                writeb(0, host->ioaddr + SDHCI_POWER_CONTROL);
 
         pwr = SDHCI_POWER_ON;
 
diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
index 3d1d21035dec..d37f46aaaea1 100644
--- a/include/linux/pci_ids.h
+++ b/include/linux/pci_ids.h
@@ -1971,6 +1971,7 @@
 #define PCI_DEVICE_ID_TOPIC_TP560       0x0000
 
 #define PCI_VENDOR_ID_ENE               0x1524
+#define PCI_DEVICE_ID_ENE_CB712_SD      0x0550
 #define PCI_DEVICE_ID_ENE_1211          0x1211
 #define PCI_DEVICE_ID_ENE_1225          0x1225
 #define PCI_DEVICE_ID_ENE_1410          0x1410