drivers: Add support for X-Powers AXP209 PMU

Change-Id: I1de0e656a38527b172af1d0b5bcd97acbfc03bf0
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Reviewed-on: http://review.coreboot.org/4591
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/drivers/Kconfig

@@ -37,3 +37,4 @@ source src/drivers/sil/Kconfig
 source src/drivers/spi/Kconfig
 source src/drivers/ti/Kconfig
 source src/drivers/trident/Kconfig
+source src/drivers/xpowers/Kconfig

src/drivers/Makefile.inc

@@ -34,4 +34,5 @@ subdirs-y += spi
 subdirs-y += ti
 subdirs-y += ipmi
 subdirs-y += elog
+subdirs-y += xpowers
 subdirs-$(CONFIG_ARCH_X86) += pc80

src/drivers/xpowers/Kconfig

@@ -0,0 +1 @@
+source src/drivers/xpowers/axp209/Kconfig

src/drivers/xpowers/Makefile.inc

@@ -0,0 +1 @@
+subdirs-$(CONFIG_DRIVER_XPOWERS_AXP209) += axp209

src/drivers/xpowers/axp209/Kconfig

@@ -0,0 +1,15 @@
+config DRIVER_XPOWERS_AXP209
+	bool
+	default n
+	help
+	  X-Powers AXP902 Power Management Unit
+
+if DRIVER_XPOWERS_AXP209
+
+config DRIVER_XPOWERS_AXP209_BOOTBLOCK
+	bool
+	default n
+	help
+	  Make AXP209 functionality available in he bootblock.
+
+endif # DRIVER_XPOWERS_AXP209

src/drivers/xpowers/axp209/Makefile.inc

@@ -0,0 +1,3 @@
+bootblock-$(CONFIG_DRIVER_XPOWERS_AXP209_BOOTBLOCK)	+= axp209.c
+romstage-$(CONFIG_DRIVER_XPOWERS_AXP209)		+= axp209.c
+ramstage-$(CONFIG_DRIVER_XPOWERS_AXP209)		+= axp209.c

src/drivers/xpowers/axp209/axp209.c

@@ -0,0 +1,230 @@
+/*
+ * Driver for X-Powers AXP 209 Power Management Unit
+ *
+ * Despite axp209_read/write only working on a byte at a time, there is no such
+ * limitation in the AXP209.
+ *
+ * Copyright (C) 2013  Alexandru Gagniuc <mr.nuke.me@gmail.com>
+ * Subject to the GNU GPL v2, or (at your option) any later version.
+ */
+
+#include "axp209.h"
+
+#include <device/i2c.h>
+
+/* Hide these definitions from the rest of the source, so keep them here */
+enum registers {
+	REG_POWER_STATUS	= 0x00,
+	REG_POWER_MODE		= 0x01,
+	REG_OTG_VBUS		= 0x02,
+	REG_CHIP_ID		= 0x03,
+	REG_CHIP_PWROUT_CTL	= 0x12,
+	REG_DCDC2_VOLTAGE	= 0x23,
+	REG_DCDC2_LDO3_CTL	= 0x25,
+	REG_DCDC3_VOLTAGE	= 0x27,
+	REG_LDO24_VOLTAGE	= 0x28,
+	REG_LDO3_VOLTAGE	= 0x29,
+	REG_VBUS_IPSOUT		= 0x30,
+	REG_PWROFF_VOLTAGE	= 0x31,
+	REG_SHTDWN_SETTING	= 0x32,
+};
+
+/* REG_LDO24_VOLTAGE definitions */
+#define REG_LDO24_VOLTAGE_LDO2_MASK	(0xf << 4)
+#define REG_LDO24_VOLTAGE_LDO2_VAL(x)	((x << 4) & REG_LDO24_VOLTAGE_LDO2_MASK)
+#define REG_LDO24_VOLTAGE_LDO4_MASK	(0xf << 0)
+#define REG_LDO24_VOLTAGE_LDO4_VAL(x)	((x << 0) & REG_LDO24_VOLTAGE_LDO4_MASK)
+
+/*
+ * Read and write accessors. We only work on one register at a time, but there
+ * is no limitation on the AXP209 as to how many registers we may read or write
+ * in one transaction.
+ * These return the number of bytes read/written, or an error code. In this
+ * case, they return 1 on success, or an error code otherwise.
+ */
+static int axp209_read(u8 bus, u8 reg, u8 *val)
+{
+	return i2c_read(bus, AXP209_I2C_ADDR, reg, 1, val, 1);
+}
+
+static int axp209_write(u8 bus, u8 reg, u8 val)
+{
+	return i2c_write(bus, AXP209_I2C_ADDR, reg, 1, &val, 1);
+}
+
+/**
+ * \brief Identify and initialize an AXP209 on the I²C bus
+ *
+ * @param[in] bus I²C bus to which the AXP209 is connected
+ * @return CB_SUCCES on if an AXP209 is found, or an error code otherwise.
+ */
+enum cb_err axp209_init(u8 bus)
+{
+	u8 id;
+
+	if (axp209_read(bus, REG_CHIP_ID, &id) != 1)
+		return CB_ERR;
+
+	/* From U-Boot code : Low 4 bits is chip version */
+	if ((id & 0x0f) != 0x1)
+		return CB_ERR;
+
+	return CB_SUCCESS;
+}
+
+/**
+ * \brief Configure the output voltage of DC-DC2 converter
+ *
+ * If the requested voltage is not available, the next lowest voltage will
+ * be applied.
+ * Valid values are between 700mV and 2275mV
+ *
+ * @param[in] millivolts voltage in mV units.
+ * @param[in] bus I²C bus to which the AXP209 is connected
+ * @return CB_SUCCES on success,
+ *	   CB_ERR_ARG if voltage is out of range, or an error code otherwise.
+ */
+enum cb_err axp209_set_dcdc2_voltage(u8 bus, u16 millivolts)
+{
+	u8 val;
+
+	if (millivolts < 700 || millivolts > 2275)
+		return CB_ERR_ARG;
+
+	val = (millivolts - 700) / 25;
+
+	if (axp209_write(bus, REG_DCDC2_VOLTAGE, val) != 1)
+		return CB_ERR;
+
+	return CB_SUCCESS;
+}
+
+/**
+ * \brief Configure the output voltage of DC-DC3 converter
+ *
+ * If the requested voltage is not available, the next lowest voltage will
+ * be applied.
+ * Valid values are between 700mV and 3500mV
+ *
+ * @param[in] millivolts voltage in mV units.
+ * @param[in] bus I²C bus to which the AXP209 is connected
+ * @return CB_SUCCES on success,
+ *	   CB_ERR_ARG if voltage is out of range, or an error code otherwise.
+ */
+enum cb_err axp209_set_dcdc3_voltage(u8 bus, u16 millivolts)
+{
+	u8 val;
+
+	if (millivolts < 700 || millivolts > 3500)
+		return CB_ERR_ARG;
+
+	val = (millivolts - 700) / 25;
+
+	if (axp209_write(bus, REG_DCDC3_VOLTAGE, val) != 1)
+		return CB_ERR;
+
+	return CB_SUCCESS;
+}
+
+/**
+ * \brief Configure the output voltage of LDO2 regulator
+ *
+ * If the requested voltage is not available, the next lowest voltage will
+ * be applied.
+ * Valid values are between 700mV and 3300mV
+ *
+ * @param[in] millivolts voltage in mV units.
+ * @param[in] bus I²C bus to which the AXP209 is connected
+ * @return CB_SUCCES on success,
+ *	   CB_ERR_ARG if voltage is out of range, or an error code otherwise.
+ */
+enum cb_err axp209_set_ldo2_voltage(u8 bus, u16 millivolts)
+{
+	u8 reg8, val;
+
+	if (millivolts < 1800 || millivolts > 3300)
+		return CB_ERR_ARG;
+
+	/* Try to read the register first, and stop here on error */
+	if (axp209_read(bus, REG_LDO24_VOLTAGE, &reg8) != 1)
+		return CB_ERR;
+
+	val = (millivolts - 1800) / 100;
+	reg8 &= ~REG_LDO24_VOLTAGE_LDO2_MASK;
+	reg8 |= REG_LDO24_VOLTAGE_LDO2_VAL(val);
+
+	if (axp209_write(bus, REG_LDO24_VOLTAGE, reg8) != 1)
+		return CB_ERR;
+
+	return CB_SUCCESS;
+}
+
+/**
+ * \brief Configure the output voltage of LDO4 regulator
+ *
+ * If the requested voltage is not available, the next lowest voltage will
+ * be applied.
+ * Valid values are between 700mV and 3500mV. Datasheet lists maximum voltage at
+ * 2250mV, but hardware samples go as high as 3500mV.
+ *
+ * @param[in] millivolts voltage in mV units.
+ * @param[in] bus I²C bus to which the AXP209 is connected
+ * @return CB_SUCCES on success,
+ *	   CB_ERR_ARG if voltage is out of range, or an error code otherwise.
+ */
+enum cb_err axp209_set_ldo3_voltage(u8 bus, u16 millivolts)
+{
+	u8 val;
+
+	/* Datasheet lists 2250 max, but PMU will output up to 3500mV */
+	if (millivolts < 700 || millivolts > 3500)
+		return CB_ERR_ARG;
+
+	val = (millivolts - 700) / 25;
+
+	if (axp209_write(bus, REG_LDO3_VOLTAGE, val) != 1)
+		return CB_ERR;
+
+	return CB_SUCCESS;
+}
+
+/**
+ * \brief Configure the output voltage of DC-DC2 converter
+ *
+ * If the requested voltage is not available, the next lowest voltage will
+ * be applied.
+ * Valid values are between 1250V and 3300mV
+ *
+ * @param[in] millivolts voltage in mV units.
+ * @param[in] bus I²C bus to which the AXP209 is connected
+ * @return CB_SUCCES on success,
+ *	   CB_ERR_ARG if voltage is out of range, or an error code otherwise.
+ */
+enum cb_err axp209_set_ldo4_voltage(u8 bus, u16 millivolts)
+{
+	u8 reg8, val;
+
+	if (millivolts < 1250 || millivolts > 3300)
+		return CB_ERR_ARG;
+
+	/* Try to read the register first, and stop here on error */
+	if (axp209_read(bus, REG_LDO24_VOLTAGE, &reg8) != 1)
+		return CB_ERR;
+
+	if (millivolts <= 2000)
+		val = (millivolts - 1200) / 100;
+	else if (millivolts <= 2700)
+		val = 9 + (millivolts - 2500) / 100;
+	else if (millivolts <= 2800)
+		val = 11;
+	else
+		val = 12 + (millivolts - 3000) / 100;
+
+	reg8 &= ~REG_LDO24_VOLTAGE_LDO4_MASK;
+	reg8 |= REG_LDO24_VOLTAGE_LDO4_VAL(val);
+
+	if (axp209_write(bus, REG_LDO24_VOLTAGE, reg8) != 1)
+			return CB_ERR;
+
+	return CB_SUCCESS;
+}

src/drivers/xpowers/axp209/axp209.h

@@ -0,0 +1,17 @@
+/*
+ * Definitions for X-Powers AXP 209 Power Management Unit
+ *
+ * Copyright (C) 2013  Alexandru Gagniuc <mr.nuke.me@gmail.com>
+ * Subject to the GNU GPL v2, or (at your option) any later version.
+ */
+
+#include <types.h>
+
+#define AXP209_I2C_ADDR (0x68 >> 1)
+
+enum cb_err axp209_init(u8 bus);
+enum cb_err axp209_set_dcdc2_voltage(u8 bus, u16 millivolts);
+enum cb_err axp209_set_dcdc3_voltage(u8 bus, u16 millivolts);
+enum cb_err axp209_set_ldo2_voltage(u8 bus, u16 millivolts);
+enum cb_err axp209_set_ldo3_voltage(u8 bus, u16 millivolts);
+enum cb_err axp209_set_ldo4_voltage(u8 bus, u16 millivolts);