drivers/power/pmic: Add tps65217 driver

Add a driver for the TPS65217 PMIC that is found in the Beaglebone
family of boards.

Signed-off-by: Greg Guyotte <gguyotte@ti.com>
[trini: Split and rework Greg's changes into new drivers/power
framework]
Signed-off-by: Tom Rini <trini@ti.com>
diff --git a/drivers/power/pmic/pmic_tps65217.c b/drivers/power/pmic/pmic_tps65217.c
new file mode 100644
index 0000000..36e9024
--- /dev/null
+++ b/drivers/power/pmic/pmic_tps65217.c
@@ -0,0 +1,109 @@
+/*
+ * (C) Copyright 2011-2013
+ * Texas Instruments, <www.ti.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include <power/tps65217.h>
+
+/**
+ * tps65217_reg_read() - Generic function that can read a TPS65217 register
+ * @src_reg:		 Source register address
+ * @src_val:		 Address of destination variable
+ * @return:		 0 for success, not 0 on failure.
+ */
+int tps65217_reg_read(uchar src_reg, uchar *src_val)
+{
+	return i2c_read(TPS65217_CHIP_PM, src_reg, 1, src_val, 1);
+}
+
+/**
+ *  tps65217_reg_write() - Generic function that can write a TPS65217 PMIC
+ *			   register or bit field regardless of protection
+ *			   level.
+ *
+ *  @prot_level:	   Register password protection.  Use
+ *			   TPS65217_PROT_LEVEL_NONE,
+ *			   TPS65217_PROT_LEVEL_1 or TPS65217_PROT_LEVEL_2
+ *  @dest_reg:		   Register address to write.
+ *  @dest_val:		   Value to write.
+ *  @mask:		   Bit mask (8 bits) to be applied.  Function will only
+ *			   change bits that are set in the bit mask.
+ *
+ *  @return:		   0 for success, not 0 on failure, as per the i2c API
+ */
+int tps65217_reg_write(uchar prot_level, uchar dest_reg, uchar dest_val,
+		       uchar mask)
+{
+	uchar read_val;
+	uchar xor_reg;
+	int ret;
+
+	/*
+	 * If we are affecting only a bit field, read dest_reg and apply the
+	 * mask
+	 */
+	if (mask != TPS65217_MASK_ALL_BITS) {
+		ret = i2c_read(TPS65217_CHIP_PM, dest_reg, 1, &read_val, 1);
+		if (ret)
+			return ret;
+		read_val &= (~mask);
+		read_val |= (dest_val & mask);
+		dest_val = read_val;
+	}
+
+	if (prot_level > 0) {
+		xor_reg = dest_reg ^ TPS65217_PASSWORD_UNLOCK;
+		ret = i2c_write(TPS65217_CHIP_PM, TPS65217_PASSWORD, 1,
+				&xor_reg, 1);
+		if (ret)
+			return ret;
+	}
+
+	ret = i2c_write(TPS65217_CHIP_PM, dest_reg, 1, &dest_val, 1);
+	if (ret)
+		return ret;
+
+	if (prot_level == TPS65217_PROT_LEVEL_2) {
+		ret = i2c_write(TPS65217_CHIP_PM, TPS65217_PASSWORD, 1,
+				&xor_reg, 1);
+		if (ret)
+			return ret;
+
+		ret = i2c_write(TPS65217_CHIP_PM, dest_reg, 1, &dest_val, 1);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+/**
+ * tps65217_voltage_update() - Function to change a voltage level, as this
+ *			       is a multi-step process.
+ * @dc_cntrl_reg:	       DC voltage control register to change.
+ * @volt_sel:		       New value for the voltage register
+ * @return:		       0 for success, not 0 on failure.
+ */
+int tps65217_voltage_update(uchar dc_cntrl_reg, uchar volt_sel)
+{
+	if ((dc_cntrl_reg != TPS65217_DEFDCDC1) &&
+	    (dc_cntrl_reg != TPS65217_DEFDCDC2) &&
+	    (dc_cntrl_reg != TPS65217_DEFDCDC3))
+		return 1;
+
+	/* set voltage level */
+	if (tps65217_reg_write(TPS65217_PROT_LEVEL_2, dc_cntrl_reg, volt_sel,
+			       TPS65217_MASK_ALL_BITS))
+		return 1;
+
+	/* set GO bit to initiate voltage transition */
+	if (tps65217_reg_write(TPS65217_PROT_LEVEL_2, TPS65217_DEFSLEW,
+			       TPS65217_DCDC_GO, TPS65217_DCDC_GO))
+		return 1;
+
+	return 0;
+}