power: pmic: add driver for Monolithic Power mp5416

This adds basic register access and child regulator binding
for the Monolithic MP5416 Power Management IC which integrates
four DC/DC switching converters and five LDO regulators.

Signed-off-by: Tim Harvey <tharvey@gateworks.com>
diff --git a/drivers/power/pmic/Kconfig b/drivers/power/pmic/Kconfig
index 7d51510..583fd3d 100644
--- a/drivers/power/pmic/Kconfig
+++ b/drivers/power/pmic/Kconfig
@@ -91,6 +91,21 @@
 	  The driver implements read/write operations for use with the FAN53555
 	  regulator driver and binds the regulator driver to its node.
 
+config DM_PMIC_MP5416
+	bool "Enable Driver Model for PMIC MP5416"
+	depends on DM_PMIC
+	help
+	  This config enables implementation of driver-model pmic uclass features
+	  for PMIC MP5416. The driver implements read/write operations.
+
+config SPL_DM_PMIC_MP5416
+	bool "Enable Driver Model for PMIC MP5416 in SPL stage"
+	depends on DM_PMIC
+	help
+	  This config enables implementation of driver-model pmic uclass
+	  features for PMIC MP5416. The driver implements read/write
+	  operations.
+
 config DM_PMIC_PCA9450
 	bool "Enable Driver Model for PMIC PCA9450"
 	depends on DM_PMIC
diff --git a/drivers/power/pmic/Makefile b/drivers/power/pmic/Makefile
index 9cd6c37..2b2a6dd 100644
--- a/drivers/power/pmic/Makefile
+++ b/drivers/power/pmic/Makefile
@@ -10,6 +10,7 @@
 obj-$(CONFIG_DM_PMIC_MAX8998) += max8998.o
 obj-$(CONFIG_DM_PMIC_MC34708) += mc34708.o
 obj-$(CONFIG_$(SPL_)DM_PMIC_BD71837) += bd71837.o
+obj-$(CONFIG_$(SPL_)DM_PMIC_MP5416) += mp5416.o
 obj-$(CONFIG_$(SPL_)DM_PMIC_PFUZE100) += pfuze100.o
 obj-$(CONFIG_$(SPL_)DM_PMIC_PCA9450) += pca9450.o
 obj-$(CONFIG_PMIC_S2MPS11) += s2mps11.o
diff --git a/drivers/power/pmic/mp5416.c b/drivers/power/pmic/mp5416.c
new file mode 100644
index 0000000..458c4df
--- /dev/null
+++ b/drivers/power/pmic/mp5416.c
@@ -0,0 +1,98 @@
+// SPDX-License-Identifier:      GPL-2.0+
+/*
+ * Copyright 2020 Gateworks Corporation
+ */
+#include <common.h>
+#include <errno.h>
+#include <dm.h>
+#include <i2c.h>
+#include <log.h>
+#include <power/pmic.h>
+#include <power/regulator.h>
+#include <power/mp5416.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static const struct pmic_child_info pmic_children_info[] = {
+	/* buck */
+	{ .prefix = "b", .driver = MP6416_REGULATOR_DRIVER },
+	/* ldo */
+	{ .prefix = "l", .driver = MP6416_REGULATOR_DRIVER },
+	{ },
+};
+
+static int mp5416_reg_count(struct udevice *dev)
+{
+	return MP5416_NUM_OF_REGS - 1;
+}
+
+static int mp5416_write(struct udevice *dev, uint reg, const uint8_t *buff,
+			int len)
+{
+	if (dm_i2c_write(dev, reg, buff, len)) {
+		pr_err("write error to device: %p register: %#x!", dev, reg);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int mp5416_read(struct udevice *dev, uint reg, uint8_t *buff, int len)
+{
+	if (dm_i2c_read(dev, reg, buff, len)) {
+		pr_err("read error from device: %p register: %#x!", dev, reg);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int mp5416_bind(struct udevice *dev)
+{
+	int children;
+	ofnode regulators_node;
+
+	debug("%s %s\n", __func__, dev->name);
+	regulators_node = dev_read_subnode(dev, "regulators");
+	if (!ofnode_valid(regulators_node)) {
+		debug("%s: %s regulators subnode not found!\n", __func__,
+		      dev->name);
+		return -ENXIO;
+	}
+
+	debug("%s: '%s' - found regulators subnode\n", __func__, dev->name);
+
+	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 int mp5416_probe(struct udevice *dev)
+{
+	debug("%s %s\n", __func__, dev->name);
+
+	return 0;
+}
+
+static struct dm_pmic_ops mp5416_ops = {
+	.reg_count = mp5416_reg_count,
+	.read = mp5416_read,
+	.write = mp5416_write,
+};
+
+static const struct udevice_id mp5416_ids[] = {
+	{ .compatible = "mps,mp5416", },
+	{ }
+};
+
+U_BOOT_DRIVER(pmic_mp5416) = {
+	.name = "mp5416 pmic",
+	.id = UCLASS_PMIC,
+	.of_match = mp5416_ids,
+	.bind = mp5416_bind,
+	.probe = mp5416_probe,
+	.ops = &mp5416_ops,
+};