[MMC] sdhci: support for multiple voltages

The sdhci controllers can support up to three voltage levels.  Detect which
and report back to the MMC layer.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

2 files changed, 66 insertions, 4 deletions

diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
index 405b6158cb6c..74912dcac82f 100644
--- a/drivers/mmc/sdhci.c
+++ b/drivers/mmc/sdhci.c
@@ -530,6 +530,46 @@ out:
         host->clock = clock;
 }
 
+static void sdhci_set_power(struct sdhci_host *host, unsigned short power)
+{
+        u8 pwr;
+
+        if (host->power == power)
+                return;
+
+        writeb(0, host->ioaddr + SDHCI_POWER_CONTROL);
+
+        if (power == (unsigned short)-1)
+                goto out;
+
+        pwr = SDHCI_POWER_ON;
+
+        switch (power) {
+        case MMC_VDD_170:
+        case MMC_VDD_180:
+        case MMC_VDD_190:
+                pwr |= SDHCI_POWER_180;
+                break;
+        case MMC_VDD_290:
+        case MMC_VDD_300:
+        case MMC_VDD_310:
+                pwr |= SDHCI_POWER_300;
+                break;
+        case MMC_VDD_320:
+        case MMC_VDD_330:
+        case MMC_VDD_340:
+                pwr |= SDHCI_POWER_330;
+                break;
+        default:
+                BUG();
+        }
+
+        writeb(pwr, host->ioaddr + SDHCI_POWER_CONTROL);
+
+out:
+        host->power = power;
+}
+
 /*****************************************************************************\
  *                                                                           *
  * MMC callbacks                                                             *
@@ -584,9 +624,9 @@ static void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
         sdhci_set_clock(host, ios->clock);
 
         if (ios->power_mode == MMC_POWER_OFF)
-                writeb(0, host->ioaddr + SDHCI_POWER_CONTROL);
+                sdhci_set_power(host, -1);
         else
-                writeb(0xFF, host->ioaddr + SDHCI_POWER_CONTROL);
+                sdhci_set_power(host, ios->vdd);
 
         ctrl = readb(host->ioaddr + SDHCI_HOST_CONTROL);
         if (ios->bus_width == MMC_BUS_WIDTH_4)
@@ -1046,9 +1086,23 @@ static int __devinit sdhci_probe_slot(struct pci_dev *pdev, int slot)
         mmc->ops = &sdhci_ops;
         mmc->f_min = host->max_clk / 256;
         mmc->f_max = host->max_clk;
-        mmc->ocr_avail = MMC_VDD_32_33|MMC_VDD_33_34;
         mmc->caps = MMC_CAP_4_BIT_DATA;
 
+        mmc->ocr_avail = 0;
+        if (caps & SDHCI_CAN_VDD_330)
+                mmc->ocr_avail |= MMC_VDD_32_33|MMC_VDD_33_34;
+        else if (caps & SDHCI_CAN_VDD_300)
+                mmc->ocr_avail |= MMC_VDD_29_30|MMC_VDD_30_31;
+        else if (caps & SDHCI_CAN_VDD_180)
+                mmc->ocr_avail |= MMC_VDD_17_18|MMC_VDD_18_19;
+
+        if (mmc->ocr_avail == 0) {
+                printk(KERN_ERR "%s: Hardware doesn't report any "
+                        "support voltages.\n", host->slot_descr);
+                ret = -ENODEV;
+                goto unmap;
+        }
+
         spin_lock_init(&host->lock);
 
         /*
diff --git a/drivers/mmc/sdhci.h b/drivers/mmc/sdhci.h
index 3b270ef486b4..aed4abd37bfd 100644
--- a/drivers/mmc/sdhci.h
+++ b/drivers/mmc/sdhci.h
@@ -67,6 +67,10 @@
 #define  SDHCI_CTRL_4BITBUS     0x02
 
 #define SDHCI_POWER_CONTROL     0x29
+#define  SDHCI_POWER_ON         0x01
+#define  SDHCI_POWER_180        0x0A
+#define  SDHCI_POWER_300        0x0C
+#define  SDHCI_POWER_330        0x0E
 
 #define SDHCI_BLOCK_GAP_CONTROL 0x2A
 
@@ -121,9 +125,12 @@
 /* 3E-3F reserved */
 
 #define SDHCI_CAPABILITIES      0x40
-#define  SDHCI_CAN_DO_DMA       0x00400000
 #define  SDHCI_CLOCK_BASE_MASK  0x00003F00
 #define  SDHCI_CLOCK_BASE_SHIFT 8
+#define  SDHCI_CAN_DO_DMA       0x00400000
+#define  SDHCI_CAN_VDD_330      0x01000000
+#define  SDHCI_CAN_VDD_300      0x02000000
+#define  SDHCI_CAN_VDD_180      0x04000000
 
 /* 44-47 reserved for more caps */
 
@@ -151,6 +158,7 @@ struct sdhci_host {
         unsigned int            max_clk;        /* Max possible freq (MHz) */
 
         unsigned int            clock;          /* Current clock (MHz) */
+        unsigned short          power;          /* Current voltage */
 
         struct mmc_request      *mrq;           /* Current request */
         struct mmc_command      *cmd;           /* Current command */