2 files changed, 105 insertions, 0 deletions

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index df6ce4a06cf3..1445ea8f10a6 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -21,6 +21,7 @@
 #include <linux/leds.h>
 #include <linux/scatterlist.h>
 #include <linux/log2.h>
+#include <linux/regulator/consumer.h>
 
 #include <linux/mmc/card.h>
 #include <linux/mmc/host.h>
@@ -523,6 +524,105 @@ u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max)
 }
 EXPORT_SYMBOL(mmc_vddrange_to_ocrmask);
 
+#ifdef CONFIG_REGULATOR
+
+/**
+ * mmc_regulator_get_ocrmask - return mask of supported voltages
+ * @supply: regulator to use
+ *
+ * This returns either a negative errno, or a mask of voltages that
+ * can be provided to MMC/SD/SDIO devices using the specified voltage
+ * regulator.  This would normally be called before registering the
+ * MMC host adapter.
+ */
+int mmc_regulator_get_ocrmask(struct regulator *supply)
+{
+        int                     result = 0;
+        int                     count;
+        int                     i;
+
+        count = regulator_count_voltages(supply);
+        if (count < 0)
+                return count;
+
+        for (i = 0; i < count; i++) {
+                int             vdd_uV;
+                int             vdd_mV;
+
+                vdd_uV = regulator_list_voltage(supply, i);
+                if (vdd_uV <= 0)
+                        continue;
+
+                vdd_mV = vdd_uV / 1000;
+                result |= mmc_vddrange_to_ocrmask(vdd_mV, vdd_mV);
+        }
+
+        return result;
+}
+EXPORT_SYMBOL(mmc_regulator_get_ocrmask);
+
+/**
+ * mmc_regulator_set_ocr - set regulator to match host->ios voltage
+ * @vdd_bit: zero for power off, else a bit number (host->ios.vdd)
+ * @supply: regulator to use
+ *
+ * Returns zero on success, else negative errno.
+ *
+ * MMC host drivers may use this to enable or disable a regulator using
+ * a particular supply voltage.  This would normally be called from the
+ * set_ios() method.
+ */
+int mmc_regulator_set_ocr(struct regulator *supply, unsigned short vdd_bit)
+{
+        int                     result = 0;
+        int                     min_uV, max_uV;
+        int                     enabled;
+
+        enabled = regulator_is_enabled(supply);
+        if (enabled < 0)
+                return enabled;
+
+        if (vdd_bit) {
+                int             tmp;
+                int             voltage;
+
+                /* REVISIT mmc_vddrange_to_ocrmask() may have set some
+                 * bits this regulator doesn't quite support ... don't
+                 * be too picky, most cards and regulators are OK with
+                 * a 0.1V range goof (it's a small error percentage).
+                 */
+                tmp = vdd_bit - ilog2(MMC_VDD_165_195);
+                if (tmp == 0) {
+                        min_uV = 1650 * 1000;
+                        max_uV = 1950 * 1000;
+                } else {
+                        min_uV = 1900 * 1000 + tmp * 100 * 1000;
+                        max_uV = min_uV + 100 * 1000;
+                }
+
+                /* avoid needless changes to this voltage; the regulator
+                 * might not allow this operation
+                 */
+                voltage = regulator_get_voltage(supply);
+                if (voltage < 0)
+                        result = voltage;
+                else if (voltage < min_uV || voltage > max_uV)
+                        result = regulator_set_voltage(supply, min_uV, max_uV);
+                else
+                        result = 0;
+
+                if (result == 0 && !enabled)
+                        result = regulator_enable(supply);
+        } else if (enabled) {
+                result = regulator_disable(supply);
+        }
+
+        return result;
+}
+EXPORT_SYMBOL(mmc_regulator_set_ocr);
+
+#endif
+
 /*
  * Mask off any voltages we don't support and select
  * the lowest voltage
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 4e457256bd33..3e7615e9087e 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -192,5 +192,10 @@ static inline void mmc_signal_sdio_irq(struct mmc_host *host)
         wake_up_process(host->sdio_irq_thread);
 }
 
+struct regulator;
+
+int mmc_regulator_get_ocrmask(struct regulator *supply);
+int mmc_regulator_set_ocr(struct regulator *supply, unsigned short vdd_bit);
+
 #endif