sunxi: power: add support for sy8106a driver

SY8106A is a PMIC which is used on the Allwinner
H3 Orange Pi Pc and Plus board. The VOUT1_SEL register is
implemented to set the default V-CPU voltage to 1200 mV.

This driver is required to ensure the SY8106A V-CPU
voltage is set to 1200 mV after a software reset. On cold
boot the default SY8106A output voltage is selected to be
1200 mV by a pair of resistors on the Orange Pi PC and Plus.

Signed-off-by: Jelle van der Waa <jelle@vdwaa.nl>
Tested-by: Siarhei Siamashka <siarhei.siamashka@gmail.com>
Acked-by: Siarhei Siamashka <siarhei.siamashka@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
diff --git a/board/sunxi/Kconfig b/board/sunxi/Kconfig
index a334aa3..5e9d3af 100644
--- a/board/sunxi/Kconfig
+++ b/board/sunxi/Kconfig
@@ -372,11 +372,14 @@
 	See I2C0_ENABLE help text.
 endif
 
+if SUNXI_GEN_SUN6I
 config R_I2C_ENABLE
 	bool "Enable the PRCM I2C/TWI controller"
-	default n
+	# This is used for the pmic on H3
+	default y if SY8106A_POWER
 	---help---
 	Set this to y to enable the I2C controller which is part of the PRCM.
+endif
 
 if MACH_SUN7I
 config I2C4_ENABLE
diff --git a/board/sunxi/board.c b/board/sunxi/board.c
index 420481a..15b7af6 100644
--- a/board/sunxi/board.c
+++ b/board/sunxi/board.c
@@ -25,6 +25,7 @@
 #include <asm/io.h>
 #include <nand.h>
 #include <net.h>
+#include <sy8106a.h>
 
 #if defined CONFIG_VIDEO_LCD_PANEL_I2C && !(defined CONFIG_SPL_BUILD)
 /* So that we can use pin names in Kconfig and sunxi_name_to_gpio() */
@@ -436,6 +437,10 @@
 	int power_failed = 0;
 	unsigned long ramsize;
 
+#ifdef CONFIG_SY8106A_POWER
+	power_failed = sy8106a_set_vout1(CONFIG_SY8106A_VOUT1_VOLT);
+#endif
+
 #if defined CONFIG_AXP152_POWER || defined CONFIG_AXP209_POWER || \
 	defined CONFIG_AXP221_POWER || defined CONFIG_AXP818_POWER
 	power_failed = axp_init();
diff --git a/configs/orangepi_pc_defconfig b/configs/orangepi_pc_defconfig
index ea9ed87..29a8da6 100644
--- a/configs/orangepi_pc_defconfig
+++ b/configs/orangepi_pc_defconfig
@@ -12,4 +12,4 @@
 # CONFIG_CMD_FLASH is not set
 # CONFIG_CMD_FPGA is not set
 CONFIG_CMD_GPIO=y
-CONFIG_R_I2C_ENABLE=y
+CONFIG_SY8106A_POWER=y
diff --git a/configs/orangepi_plus_defconfig b/configs/orangepi_plus_defconfig
index 003a9c6..d65b828 100644
--- a/configs/orangepi_plus_defconfig
+++ b/configs/orangepi_plus_defconfig
@@ -12,3 +12,4 @@
 # CONFIG_CMD_FLASH is not set
 # CONFIG_CMD_FPGA is not set
 CONFIG_CMD_GPIO=y
+CONFIG_SY8106A_POWER=y
diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index 10683a2..adc6455 100644
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -48,6 +48,13 @@
 	Say y here to enable support for the axp818 pmic found on
 	A83T dev board.
 
+config SY8106A_POWER
+	boolean "SY8106A pmic support"
+	depends on MACH_SUN8I_H3
+	---help---
+	Select this to enable support for the SY8106A pmic found on some
+	H3 boards.
+
 endchoice
 
 config AXP_DCDC1_VOLT
@@ -232,4 +239,13 @@
 	1.2V for the SSD2828 chip (converter of parallel LCD interface
 	into MIPI DSI).
 
+config SY8106A_VOUT1_VOLT
+	int "SY8106A pmic VOUT1 voltage"
+	depends on SY8106A_POWER
+	default 1200
+	---help---
+	Set the voltage (mV) to program the SY8106A pmic VOUT1. This
+	is typically used to power the VDD-CPU and should be 1200mV.
+	Values can range from 680mV till 1950mV.
+
 endmenu
diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index 0fdbca3..690faa0 100644
--- a/drivers/power/Makefile
+++ b/drivers/power/Makefile
@@ -12,6 +12,7 @@
 obj-$(CONFIG_AXP818_POWER)	+= axp818.o
 obj-$(CONFIG_EXYNOS_TMU)	+= exynos-tmu.o
 obj-$(CONFIG_FTPMU010_POWER)	+= ftpmu010.o
+obj-$(CONFIG_SY8106A_POWER)	+= sy8106a.o
 obj-$(CONFIG_TPS6586X_POWER)	+= tps6586x.o
 obj-$(CONFIG_TWL4030_POWER)	+= twl4030.o
 obj-$(CONFIG_TWL6030_POWER)	+= twl6030.o
diff --git a/drivers/power/sy8106a.c b/drivers/power/sy8106a.c
new file mode 100644
index 0000000..bbf116f
--- /dev/null
+++ b/drivers/power/sy8106a.c
@@ -0,0 +1,29 @@
+/*
+ * (C) Copyright 2016
+ * Jelle van der Waa <jelle@vdwaa.nl>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+#include <common.h>
+#include <i2c.h>
+#include <sy8106a.h>
+
+#define SY8106A_I2C_ADDR 0x65
+#define SY8106A_VOUT1_SEL 1
+#define SY8106A_VOUT1_SEL_ENABLE (1 << 7)
+
+static u8 sy8106a_mvolt_to_cfg(int mvolt, int min, int max, int div)
+{
+	if (mvolt < min)
+		mvolt = min;
+	else if (mvolt > max)
+		mvolt = max;
+
+	return (mvolt - min) / div;
+}
+
+int sy8106a_set_vout1(unsigned int mvolt)
+{
+	u8 data = sy8106a_mvolt_to_cfg(mvolt, 680, 1950, 10) | SY8106A_VOUT1_SEL_ENABLE;
+	return i2c_write(SY8106A_I2C_ADDR, SY8106A_VOUT1_SEL, 1, &data, 1);
+}
diff --git a/include/configs/sunxi-common.h b/include/configs/sunxi-common.h
index b4dfb3c..40850e5 100644
--- a/include/configs/sunxi-common.h
+++ b/include/configs/sunxi-common.h
@@ -206,7 +206,8 @@
 #define CONFIG_SPL_STACK		LOW_LEVEL_SRAM_STACK
 
 /* I2C */
-#if defined CONFIG_AXP152_POWER || defined CONFIG_AXP209_POWER
+#if defined CONFIG_AXP152_POWER || defined CONFIG_AXP209_POWER || \
+    defined CONFIG_SY8106A_POWER
 #define CONFIG_SPL_I2C_SUPPORT
 #endif
 
@@ -240,7 +241,8 @@
 
 /* PMU */
 #if defined CONFIG_AXP152_POWER || defined CONFIG_AXP209_POWER || \
-    defined CONFIG_AXP221_POWER || defined CONFIG_AXP818_POWER
+    defined CONFIG_AXP221_POWER || defined CONFIG_AXP818_POWER || \
+    defined CONFIG_SY8106A_POWER
 #define CONFIG_SPL_POWER_SUPPORT
 #endif
 
diff --git a/include/sy8106a.h b/include/sy8106a.h
new file mode 100644
index 0000000..32e8c43
--- /dev/null
+++ b/include/sy8106a.h
@@ -0,0 +1,11 @@
+/*
+ * (C) Copyright 2016
+ * Jelle van der Waa <jelle@vdwaa.nl>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+#ifndef _SY8106A_PMIC_H_
+
+int sy8106a_set_vout1(unsigned int mvolt);
+
+#endif