power: Add AMS AS3722 PMIC support

The AS3722 provides a number of DC/DC converters and LDOs as well as 8
GPIOs.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>

2 files changed, 265 insertions, 0 deletions

diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index 04bd996cad..214565241e 100644
--- a/drivers/power/Makefile
+++ b/drivers/power/Makefile
@@ -5,6 +5,7 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
+obj-$(CONFIG_AS3722_POWER)	+= as3722.o
 obj-$(CONFIG_AXP152_POWER)	+= axp152.o
 obj-$(CONFIG_AXP209_POWER)	+= axp209.o
 obj-$(CONFIG_AXP221_POWER)	+= axp221.o
diff --git a/drivers/power/as3722.c b/drivers/power/as3722.c
new file mode 100644
index 0000000000..4c6de79cd6
--- /dev/null
+++ b/drivers/power/as3722.c
@@ -0,0 +1,264 @@
+/*
+ * Copyright (C) 2014 NVIDIA Corporation
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#define pr_fmt(fmt) "as3722: " fmt
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <fdtdec.h>
+#include <i2c.h>
+
+#include <power/as3722.h>
+
+#define AS3722_SD_VOLTAGE(n) (0x00 + (n))
+#define AS3722_GPIO_CONTROL(n) (0x08 + (n))
+#define  AS3722_GPIO_CONTROL_MODE_OUTPUT_VDDH (1 << 0)
+#define  AS3722_GPIO_CONTROL_MODE_OUTPUT_VDDL (7 << 0)
+#define  AS3722_GPIO_CONTROL_INVERT (1 << 7)
+#define AS3722_LDO_VOLTAGE(n) (0x10 + (n))
+#define AS3722_GPIO_SIGNAL_OUT 0x20
+#define AS3722_SD_CONTROL 0x4d
+#define AS3722_LDO_CONTROL 0x4e
+#define AS3722_ASIC_ID1 0x90
+#define  AS3722_DEVICE_ID 0x0c
+#define AS3722_ASIC_ID2 0x91
+
+static int as3722_read(struct udevice *pmic, u8 reg, u8 *value)
+{
+	int err;
+
+	err = i2c_read(pmic, reg, value, 1);
+	if (err < 0)
+		return err;
+
+	return 0;
+}
+
+static int as3722_write(struct udevice *pmic, u8 reg, u8 value)
+{
+	int err;
+
+	err = i2c_write(pmic, reg, &value, 1);
+	if (err < 0)
+		return err;
+
+	return 0;
+}
+
+static int as3722_read_id(struct udevice *pmic, u8 *id, u8 *revision)
+{
+	int err;
+
+	err = as3722_read(pmic, AS3722_ASIC_ID1, id);
+	if (err) {
+		error("failed to read ID1 register: %d", err);
+		return err;
+	}
+
+	err = as3722_read(pmic, AS3722_ASIC_ID2, revision);
+	if (err) {
+		error("failed to read ID2 register: %d", err);
+		return err;
+	}
+
+	return 0;
+}
+
+int as3722_sd_enable(struct udevice *pmic, unsigned int sd)
+{
+	u8 value;
+	int err;
+
+	if (sd > 6)
+		return -EINVAL;
+
+	err = as3722_read(pmic, AS3722_SD_CONTROL, &value);
+	if (err) {
+		error("failed to read SD control register: %d", err);
+		return err;
+	}
+
+	value |= 1 << sd;
+
+	err = as3722_write(pmic, AS3722_SD_CONTROL, value);
+	if (err < 0) {
+		error("failed to write SD control register: %d", err);
+		return err;
+	}
+
+	return 0;
+}
+
+int as3722_sd_set_voltage(struct udevice *pmic, unsigned int sd, u8 value)
+{
+	int err;
+
+	if (sd > 6)
+		return -EINVAL;
+
+	err = as3722_write(pmic, AS3722_SD_VOLTAGE(sd), value);
+	if (err < 0) {
+		error("failed to write SD%u voltage register: %d", sd, err);
+		return err;
+	}
+
+	return 0;
+}
+
+int as3722_ldo_enable(struct udevice *pmic, unsigned int ldo)
+{
+	u8 value;
+	int err;
+
+	if (ldo > 11)
+		return -EINVAL;
+
+	err = as3722_read(pmic, AS3722_LDO_CONTROL, &value);
+	if (err) {
+		error("failed to read LDO control register: %d", err);
+		return err;
+	}
+
+	value |= 1 << ldo;
+
+	err = as3722_write(pmic, AS3722_LDO_CONTROL, value);
+	if (err < 0) {
+		error("failed to write LDO control register: %d", err);
+		return err;
+	}
+
+	return 0;
+}
+
+int as3722_ldo_set_voltage(struct udevice *pmic, unsigned int ldo, u8 value)
+{
+	int err;
+
+	if (ldo > 11)
+		return -EINVAL;
+
+	err = as3722_write(pmic, AS3722_LDO_VOLTAGE(ldo), value);
+	if (err < 0) {
+		error("failed to write LDO%u voltage register: %d", ldo,
+		      err);
+		return err;
+	}
+
+	return 0;
+}
+
+int as3722_gpio_configure(struct udevice *pmic, unsigned int gpio,
+			  unsigned long flags)
+{
+	u8 value = 0;
+	int err;
+
+	if (flags & AS3722_GPIO_OUTPUT_VDDH)
+		value |= AS3722_GPIO_CONTROL_MODE_OUTPUT_VDDH;
+
+	if (flags & AS3722_GPIO_INVERT)
+		value |= AS3722_GPIO_CONTROL_INVERT;
+
+	err = as3722_write(pmic, AS3722_GPIO_CONTROL(gpio), value);
+	if (err) {
+		error("failed to configure GPIO#%u: %d", gpio, err);
+		return err;
+	}
+
+	return 0;
+}
+
+static int as3722_gpio_set(struct udevice *pmic, unsigned int gpio,
+			   unsigned int level)
+{
+	const char *l;
+	u8 value;
+	int err;
+
+	if (gpio > 7)
+		return -EINVAL;
+
+	err = as3722_read(pmic, AS3722_GPIO_SIGNAL_OUT, &value);
+	if (err < 0) {
+		error("failed to read GPIO signal out register: %d", err);
+		return err;
+	}
+
+	if (level == 0) {
+		value &= ~(1 << gpio);
+		l = "low";
+	} else {
+		value |= 1 << gpio;
+		l = "high";
+	}
+
+	err = as3722_write(pmic, AS3722_GPIO_SIGNAL_OUT, value);
+	if (err) {
+		error("failed to set GPIO#%u %s: %d", gpio, l, err);
+		return err;
+	}
+
+	return 0;
+}
+
+int as3722_gpio_direction_output(struct udevice *pmic, unsigned int gpio,
+				 unsigned int level)
+{
+	u8 value;
+	int err;
+
+	if (gpio > 7)
+		return -EINVAL;
+
+	if (level == 0)
+		value = AS3722_GPIO_CONTROL_MODE_OUTPUT_VDDL;
+	else
+		value = AS3722_GPIO_CONTROL_MODE_OUTPUT_VDDH;
+
+	err = as3722_write(pmic, AS3722_GPIO_CONTROL(gpio), value);
+	if (err) {
+		error("failed to configure GPIO#%u as output: %d", gpio, err);
+		return err;
+	}
+
+	err = as3722_gpio_set(pmic, gpio, level);
+	if (err < 0) {
+		error("failed to set GPIO#%u high: %d", gpio, err);
+		return err;
+	}
+
+	return 0;
+}
+
+int as3722_init(struct udevice **devp)
+{
+	struct udevice *pmic;
+	u8 id, revision;
+	const unsigned int bus = 0;
+	const unsigned int address = 0x40;
+	int err;
+
+	err = i2c_get_chip_for_busnum(bus, address, &pmic);
+	if (err)
+		return err;
+	err = as3722_read_id(pmic, &id, &revision);
+	if (err < 0) {
+		error("failed to read ID: %d", err);
+		return err;
+	}
+
+	if (id != AS3722_DEVICE_ID) {
+		error("unknown device");
+		return -ENOENT;
+	}
+
+	debug("AS3722 revision %#x found on I2C bus %u, address %#x\n",
+	      revision, bus, address);
+	*devp = pmic;
+
+	return 0;
+}