power: pmic: Palmas: Add the base pmic support

Add support to bind the regulators/child nodes with the pmic.
Also adds the pmic i2c based read/write funtions to access pmic
registers.

Signed-off-by: Keerthy <j-keerthy@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>

drivers/power/pmic/Kconfig

@@ -143,3 +143,10 @@ config PMIC_TPS65090
 	FETs and a battery charger. This driver provides register access
 	only, and you can enable the regulator/charger drivers separately if
 	required.
+
+config PMIC_PALMAS
+	bool "Enable driver for Texas Instruments PALMAS PMIC"
+	depends on DM_PMIC
+	---help---
+	The PALMAS is a PMIC containing several LDOs, SMPS.
+	This driver binds the pmic children.

drivers/power/pmic/Makefile

@@ -16,6 +16,7 @@ obj-$(CONFIG_PMIC_RK808) += rk808.o
 obj-$(CONFIG_PMIC_RN5T567) += rn5t567.o
 obj-$(CONFIG_PMIC_TPS65090) += tps65090.o
 obj-$(CONFIG_PMIC_S5M8767) += s5m8767.o
+obj-$(CONFIG_$(SPL_)PMIC_PALMAS) += palmas.o
 
 obj-$(CONFIG_POWER_LTC3676) += pmic_ltc3676.o
 obj-$(CONFIG_POWER_MAX77696) += pmic_max77696.o

drivers/power/pmic/palmas.c

@@ -0,0 +1,104 @@
+/*
+ * (C) Copyright 2016 Texas Instruments Incorporated, <www.ti.com>
+ * Keerthy <j-keerthy@ti.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <fdtdec.h>
+#include <errno.h>
+#include <dm.h>
+#include <i2c.h>
+#include <power/pmic.h>
+#include <power/regulator.h>
+#include <power/palmas.h>
+#include <dm/device.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static const struct pmic_child_info pmic_children_info[] = {
+	{ .prefix = "ldo", .driver = PALMAS_LDO_DRIVER },
+	{ .prefix = "smps", .driver = PALMAS_SMPS_DRIVER },
+	{ },
+};
+
+static int palmas_write(struct udevice *dev, uint reg, const uint8_t *buff,
+			  int len)
+{
+	if (dm_i2c_write(dev, reg, buff, len)) {
+		error("write error to device: %p register: %#x!", dev, reg);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int palmas_read(struct udevice *dev, uint reg, uint8_t *buff, int len)
+{
+	if (dm_i2c_read(dev, reg, buff, len)) {
+		error("read error from device: %p register: %#x!", dev, reg);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int palmas_bind(struct udevice *dev)
+{
+	int pmic_node = -1, regulators_node;
+	const void *blob = gd->fdt_blob;
+	int children;
+	int node = dev->of_offset;
+	int subnode, len;
+
+	fdt_for_each_subnode(blob, subnode, node) {
+		const char *name;
+		char *temp;
+
+		name = fdt_get_name(blob, subnode, &len);
+		temp = strstr(name, "pmic");
+		if (temp) {
+			pmic_node = subnode;
+			break;
+		}
+	}
+
+	if (pmic_node <= 0) {
+		debug("%s: %s pmic subnode not found!", __func__, dev->name);
+		return -ENXIO;
+	}
+
+	regulators_node = fdt_subnode_offset(blob, pmic_node, "regulators");
+
+	if (regulators_node <= 0) {
+		debug("%s: %s reg subnode not found!", __func__, dev->name);
+		return -ENXIO;
+	}
+
+	children = pmic_bind_children(dev, regulators_node, pmic_children_info);
+	if (!children)
+		debug("%s: %s - no child found\n", __func__, dev->name);
+
+	/* Always return success for this device */
+	return 0;
+}
+
+static struct dm_pmic_ops palmas_ops = {
+	.read = palmas_read,
+	.write = palmas_write,
+};
+
+static const struct udevice_id palmas_ids[] = {
+	{ .compatible = "ti,tps659038", .data = TPS659038 },
+	{ .compatible = "ti,tps65917" , .data = TPS65917 },
+	{ }
+};
+
+U_BOOT_DRIVER(pmic_palmas) = {
+	.name = "palmas_pmic",
+	.id = UCLASS_PMIC,
+	.of_match = palmas_ids,
+	.bind = palmas_bind,
+	.ops = &palmas_ops,
+};

include/power/palmas.h

@@ -0,0 +1,25 @@
+#define	PALMAS		0x0
+#define TPS659038	0x1
+#define TPS65917	0x2
+
+/* I2C device address for pmic palmas */
+#define PALMAS_I2C_ADDR	(0x12 >> 1)
+#define PALMAS_LDO_NUM		11
+#define PALMAS_SMPS_NUM	8
+
+/* Drivers name */
+#define PALMAS_LDO_DRIVER     "palmas_ldo"
+#define PALMAS_SMPS_DRIVER    "palmas_smps"
+
+#define PALMAS_SMPS_VOLT_MASK		0x7F
+#define PALMAS_SMPS_RANGE_MASK		0x80
+#define PALMAS_SMPS_VOLT_MAX_HEX	0x7F
+#define PALMAS_SMPS_VOLT_MAX		3300000
+#define PALMAS_SMPS_MODE_MASK		0x3
+#define	PALMAS_SMPS_STATUS_MASK		0x30
+
+#define PALMAS_LDO_VOLT_MASK    0x3F
+#define PALMAS_LDO_VOLT_MAX_HEX 0x3F
+#define PALMAS_LDO_VOLT_MAX     3300000
+#define PALMAS_LDO_MODE_MASK	0x1
+#define PALMAS_LDO_STATUS_MASK	0x10