Merge tag 'mmc-updates-for-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel...

[pandora-kernel.git] / drivers / mmc / core / core.c

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 5d08855..bf18b6b 100644 (file)
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -27,6 +27,7 @@
 #include <linux/fault-inject.h>
 #include <linux/random.h>
 #include <linux/slab.h>
+#include <linux/of.h>
 
 #include <linux/mmc/card.h>
 #include <linux/mmc/host.h>
@@ -1196,6 +1197,49 @@ u32 mmc_vddrange_to_ocrmask(int vdd_min, int vdd_max)
 }
 EXPORT_SYMBOL(mmc_vddrange_to_ocrmask);
 
+#ifdef CONFIG_OF
+
+/**
+ * mmc_of_parse_voltage - return mask of supported voltages
+ * @np: The device node need to be parsed.
+ * @mask: mask of voltages available for MMC/SD/SDIO
+ *
+ * 1. Return zero on success.
+ * 2. Return negative errno: voltage-range is invalid.
+ */
+int mmc_of_parse_voltage(struct device_node *np, u32 *mask)
+{
+       const u32 *voltage_ranges;
+       int num_ranges, i;
+
+       voltage_ranges = of_get_property(np, "voltage-ranges", &num_ranges);
+       num_ranges = num_ranges / sizeof(*voltage_ranges) / 2;
+       if (!voltage_ranges || !num_ranges) {
+               pr_info("%s: voltage-ranges unspecified\n", np->full_name);
+               return -EINVAL;
+       }
+
+       for (i = 0; i < num_ranges; i++) {
+               const int j = i * 2;
+               u32 ocr_mask;
+
+               ocr_mask = mmc_vddrange_to_ocrmask(
+                               be32_to_cpu(voltage_ranges[j]),
+                               be32_to_cpu(voltage_ranges[j + 1]));
+               if (!ocr_mask) {
+                       pr_err("%s: voltage-range #%d is invalid\n",
+                               np->full_name, i);
+                       return -EINVAL;
+               }
+               *mask |= ocr_mask;
+       }
+
+       return 0;
+}
+EXPORT_SYMBOL(mmc_of_parse_voltage);
+
+#endif /* CONFIG_OF */
+
 #ifdef CONFIG_REGULATOR
 
 /**