mfd: Allow configuration of VDCDC2 for tps65010

Add function to allow the configuation fo the VDCDC2 register by
external users, to allow changing of the standard and low-power
running modes.

This is needed, for example, for the Simtec IM2440D20 where we need
to use the low-power mode to shutdown the LDO/DCDC that are not needed
during suspend (saving substantial power) and the runtime use of the
low-power mode to change VCore.

Signed-off-by: Ben Dooks <ben@simtec.co.uk>
Signed-off-by: Simtec Linux Team <linux@simtec.co.uk>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/tps65010.c b/drivers/mfd/tps65010.c
index 755c403..e595530 100644
--- a/drivers/mfd/tps65010.c
+++ b/drivers/mfd/tps65010.c
@@ -964,6 +964,34 @@
 }
 EXPORT_SYMBOL(tps65010_config_vregs1);
 
+int tps65010_config_vdcdc2(unsigned value)
+{
+	struct i2c_client *c;
+	int	 status;
+
+	if (!the_tps)
+		return -ENODEV;
+
+	c = the_tps->client;
+	mutex_lock(&the_tps->lock);
+
+	pr_debug("%s: vdcdc2 0x%02x\n", DRIVER_NAME,
+		 i2c_smbus_read_byte_data(c, TPS_VDCDC2));
+
+	status = i2c_smbus_write_byte_data(c, TPS_VDCDC2, value);
+
+	if (status != 0)
+		printk(KERN_ERR "%s: Failed to write vdcdc2 register\n",
+			DRIVER_NAME);
+	else
+		pr_debug("%s: vregs1 0x%02x\n", DRIVER_NAME,
+			 i2c_smbus_read_byte_data(c, TPS_VDCDC2));
+
+	mutex_unlock(&the_tps->lock);
+	return status;
+}
+EXPORT_SYMBOL(tps65010_config_vdcdc2);
+
 /*-------------------------------------------------------------------------*/
 /* tps65013_set_low_pwr parameter:
  * mode: ON or OFF