pmic: Add support for Qualcomm PM8916 PMIC

This PMIC is connected on SPMI bus so needs SPMI support enabled.

Signed-off-by: Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/power/pmic/pm8916.c b/drivers/power/pmic/pm8916.c
new file mode 100644
index 0000000..9acf5f5
--- /dev/null
+++ b/drivers/power/pmic/pm8916.c
@@ -0,0 +1,96 @@
+/*
+ * Qualcomm pm8916 pmic driver
+ *
+ * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+#include <common.h>
+#include <dm.h>
+#include <dm/root.h>
+#include <power/pmic.h>
+#include <spmi/spmi.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define PID_SHIFT 8
+#define PID_MASK (0xFF << PID_SHIFT)
+#define REG_MASK 0xFF
+
+struct pm8916_priv {
+	uint16_t usid; /* Slave ID on SPMI bus */
+};
+
+static int pm8916_reg_count(struct udevice *dev)
+{
+	return 0xFFFF;
+}
+
+static int pm8916_write(struct udevice *dev, uint reg, const uint8_t *buff,
+			int len)
+{
+	struct pm8916_priv *priv = dev_get_priv(dev);
+
+	if (len != 1)
+		return -EINVAL;
+
+	return spmi_reg_write(dev->parent, priv->usid,
+			      (reg & PID_MASK) >> PID_SHIFT, reg & REG_MASK,
+			      *buff);
+}
+
+static int pm8916_read(struct udevice *dev, uint reg, uint8_t *buff, int len)
+{
+	struct pm8916_priv *priv = dev_get_priv(dev);
+	int val;
+
+	if (len != 1)
+		return -EINVAL;
+
+	val = spmi_reg_read(dev->parent, priv->usid,
+			    (reg & PID_MASK) >> PID_SHIFT, reg & REG_MASK);
+
+	if (val < 0)
+		return val;
+	*buff = val;
+	return 0;
+}
+
+static struct dm_pmic_ops pm8916_ops = {
+	.reg_count = pm8916_reg_count,
+	.read = pm8916_read,
+	.write = pm8916_write,
+};
+
+static const struct udevice_id pm8916_ids[] = {
+	{ .compatible = "qcom,spmi-pmic" },
+	{ }
+};
+
+static int pm8916_probe(struct udevice *dev)
+{
+	struct pm8916_priv *priv = dev_get_priv(dev);
+
+	priv->usid = dev_get_addr(dev);
+
+	if (priv->usid == FDT_ADDR_T_NONE)
+		return -EINVAL;
+
+	return 0;
+}
+
+
+static int pm8916_bind(struct udevice *dev)
+{
+	return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
+}
+
+U_BOOT_DRIVER(pmic_pm8916) = {
+	.name = "pmic_pm8916",
+	.id = UCLASS_PMIC,
+	.of_match = pm8916_ids,
+	.bind = pm8916_bind,
+	.probe = pm8916_probe,
+	.ops = &pm8916_ops,
+	.priv_auto_alloc_size = sizeof(struct pm8916_priv),
+};