power: Add new PMIC PCA9450 driver

PCA9450 PMIC series is used to support iMX8MM (PCA9450A) and
iMX8MN (PCA9450B). Add the PMIC driver for both PCA9450A and PCA9450B.

Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Signed-off-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/drivers/power/pmic/pca9450.c b/drivers/power/pmic/pca9450.c
new file mode 100644
index 0000000..77986c4
--- /dev/null
+++ b/drivers/power/pmic/pca9450.c
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2019 NXP
+ */
+
+#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/pca9450.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static const struct pmic_child_info pmic_children_info[] = {
+	/* buck */
+	{ .prefix = "b", .driver = PCA9450_REGULATOR_DRIVER},
+	/* ldo */
+	{ .prefix = "l", .driver = PCA9450_REGULATOR_DRIVER},
+	{ },
+};
+
+static int pca9450_reg_count(struct udevice *dev)
+{
+	return PCA9450_REG_NUM;
+}
+
+static int pca9450_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 pca9450_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 pca9450_bind(struct udevice *dev)
+{
+	int children;
+	ofnode regulators_node;
+
+	regulators_node = dev_read_subnode(dev, "regulators");
+	if (!ofnode_valid(regulators_node)) {
+		debug("%s: %s regulators subnode not found!", __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 struct dm_pmic_ops pca9450_ops = {
+	.reg_count = pca9450_reg_count,
+	.read = pca9450_read,
+	.write = pca9450_write,
+};
+
+static const struct udevice_id pca9450_ids[] = {
+	{ .compatible = "nxp,pca9450a", .data = 0x35, },
+	{ .compatible = "nxp,pca9450b", .data = 0x25, },
+	{ }
+};
+
+U_BOOT_DRIVER(pmic_pca9450) = {
+	.name = "pca9450 pmic",
+	.id = UCLASS_PMIC,
+	.of_match = pca9450_ids,
+	.bind = pca9450_bind,
+	.ops = &pca9450_ops,
+};