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>

5 files changed, 330 insertions, 0 deletions

diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index dc64e4d32b..b3097316e2 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_EXYNOS_TMU)	+= exynos-tmu.o
diff --git a/drivers/power/as3722.c b/drivers/power/as3722.c
new file mode 100644
index 0000000000..59d1bf1b50
--- /dev/null
+++ b/drivers/power/as3722.c
@@ -0,0 +1,300 @@
+/*
+ * Copyright (C) 2014 NVIDIA Corporation
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#define pr_fmt(fmt) "as3722: " fmt
+
+#include <common.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
+
+struct as3722 {
+	struct i2c_client client;
+	u8 address;
+};
+
+static struct as3722 as3722_pmic;
+
+static int as3722_read(struct as3722 *pmic, u8 reg, u8 *value)
+{
+	int err;
+
+	err = i2c_client_read(&pmic->client, reg, 1, value, 1);
+	if (err < 0)
+		return err;
+
+	return 0;
+}
+
+static int as3722_write(struct as3722 *pmic, u8 reg, u8 value)
+{
+	int err;
+
+	err = i2c_client_write(&pmic->client, reg, 1, &value, 1);
+	if (err < 0)
+		return err;
+
+	return 0;
+}
+
+static int as3722_read_id(struct as3722 *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 as3722 *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 as3722 *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 as3722 *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 as3722 *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 as3722 *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 as3722 *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 as3722 *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 as3722 **pmicp, const void *fdt)
+{
+	struct as3722 *pmic = &as3722_pmic;
+	int count, nodes[1], i;
+	int err;
+
+	count = fdtdec_find_aliases_for_id(fdt, NULL, COMPAT_AMS_AS3722,
+					   nodes, ARRAY_SIZE(nodes));
+	for (i = 0; i < count; i++) {
+		int parent = fdt_parent_offset(fdt, nodes[i]), bus;
+		struct i2c_adapter *adapter;
+		fdt_addr_t address;
+		u8 id, revision;
+
+		bus = i2c_get_bus_num_fdt(parent);
+		if (bus < 0) {
+			error("invalid bus %d", bus);
+			continue;
+		}
+
+		address = fdtdec_get_addr(fdt, nodes[i], "reg");
+		if (address == FDT_ADDR_T_NONE) {
+			error("slave address not found");
+			continue;
+		}
+
+		adapter = i2c_adapter_get(bus);
+		if (!adapter) {
+			error("I2C adapter for bus %d not found", bus);
+			continue;
+		}
+
+		err = i2c_client_init(&pmic->client, adapter, address);
+		if (err < 0) {
+			error("failed to initialize I2C slave: %d", err);
+			continue;
+		}
+
+		err = as3722_read_id(pmic, &id, &revision);
+		if (err < 0) {
+			error("failed to read ID: %d", err);
+			continue;
+		}
+
+		if (id != AS3722_DEVICE_ID) {
+			error("unknown device");
+			continue;
+		}
+
+		debug("AS3722 revision %#x found on I2C bus %u, address %#x\n",
+		      revision, bus, address);
+
+		*pmicp = pmic;
+		return 0;
+	}
+
+	return -ENODEV;
+}
diff --git a/include/fdtdec.h b/include/fdtdec.h
index 99cb353804..6b1e7e511c 100644
--- a/include/fdtdec.h
+++ b/include/fdtdec.h
@@ -117,6 +117,7 @@ enum fdt_compat_id {
 	COMPAT_NXP_PTN3460,		/* NXP PTN3460 DP/LVDS bridge */
 	COMPAT_SAMSUNG_EXYNOS_SYSMMU,	/* Exynos sysmmu */
 	COMPAT_PARADE_PS8625,		/* Parade PS8622 EDP->LVDS bridge */
+	COMPAT_AMS_AS3722,		/* AMS AS3722 PMIC */
 
 	COMPAT_COUNT,
 };
diff --git a/include/power/as3722.h b/include/power/as3722.h
new file mode 100644
index 0000000000..2c2e45a44b
--- /dev/null
+++ b/include/power/as3722.h
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2014 NVIDIA Corporation
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#ifndef __POWER_AS3722_H__
+#define __POWER_AS3722_H__
+
+#include <asm/types.h>
+
+#define AS3722_GPIO_OUTPUT_VDDH (1 << 0)
+#define AS3722_GPIO_INVERT (1 << 1)
+
+struct as3722;
+
+int as3722_init(struct as3722 **pmic, const void *fdt);
+int as3722_sd_enable(struct as3722 *pmic, unsigned int sd);
+int as3722_sd_set_voltage(struct as3722 *pmic, unsigned int sd, u8 value);
+int as3722_ldo_enable(struct as3722 *pmic, unsigned int ldo);
+int as3722_ldo_set_voltage(struct as3722 *pmic, unsigned int ldo, u8 value);
+int as3722_gpio_configure(struct as3722 *pmic, unsigned int gpio,
+			  unsigned long flags);
+int as3722_gpio_direction_output(struct as3722 *pmic, unsigned int gpio,
+				 unsigned int level);
+
+#endif /* __POWER_AS3722_H__ */
diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index 4f66ae172f..db5a859bb0 100644
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -72,6 +72,7 @@ static const char * const compat_names[COMPAT_COUNT] = {
 	COMPAT(COMPAT_NXP_PTN3460, "nxp,ptn3460"),
 	COMPAT(SAMSUNG_EXYNOS_SYSMMU, "samsung,sysmmu-v3.3"),
 	COMPAT(PARADE_PS8625, "parade,ps8625"),
+	COMPAT(AMS_AS3722, "ams,as3722"),
 };
 
 const char *fdtdec_get_compatible(enum fdt_compat_id id)