Add I2C driver for Summit Microelectronics SMB347 Battery Charger.

Driver support for the Summit I²C battery charger. This is used in some
Intel devices.

Signed-off-by: Bruce E. Robertson <bruce.e.robertson@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>

drivers/power/Kconfig

@@ -274,4 +274,11 @@ config CHARGER_MAX8998
 	  Say Y to enable support for the battery charger control sysfs and
 	  platform data of MAX8998/LP3974 PMICs.
 
+config CHARGER_SMB347
+	tristate "Summit Microelectronics SMB347 Battery Charger"
+	depends on I2C
+	help
+	  Say Y to include support for Summit Microelectronics SMB347
+	  Battery Charger.
+
 endif # POWER_SUPPLY

drivers/power/Makefile

@@ -41,3 +41,4 @@ obj-$(CONFIG_CHARGER_GPIO)	+= gpio-charger.o
 obj-$(CONFIG_CHARGER_MANAGER)	+= charger-manager.o
 obj-$(CONFIG_CHARGER_MAX8997)	+= max8997_charger.o
 obj-$(CONFIG_CHARGER_MAX8998)	+= max8998_charger.o
+obj-$(CONFIG_CHARGER_SMB347)	+= smb347-charger.o

include/linux/power/smb347-charger.h

@@ -0,0 +1,117 @@
+/*
+ * Summit Microelectronics SMB347 Battery Charger Driver
+ *
+ * Copyright (C) 2011, Intel Corporation
+ *
+ * Authors: Bruce E. Robertson <bruce.e.robertson@intel.com>
+ *          Mika Westerberg <mika.westerberg@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef SMB347_CHARGER_H
+#define SMB347_CHARGER_H
+
+#include <linux/types.h>
+#include <linux/power_supply.h>
+
+enum {
+	/* use the default compensation method */
+	SMB347_SOFT_TEMP_COMPENSATE_DEFAULT = -1,
+
+	SMB347_SOFT_TEMP_COMPENSATE_NONE,
+	SMB347_SOFT_TEMP_COMPENSATE_CURRENT,
+	SMB347_SOFT_TEMP_COMPENSATE_VOLTAGE,
+};
+
+/* Use default factory programmed value for hard/soft temperature limit */
+#define SMB347_TEMP_USE_DEFAULT		-273
+
+/*
+ * Charging enable can be controlled by software (via i2c) by
+ * smb347-charger driver or by EN pin (active low/high).
+ */
+enum smb347_chg_enable {
+	SMB347_CHG_ENABLE_SW,
+	SMB347_CHG_ENABLE_PIN_ACTIVE_LOW,
+	SMB347_CHG_ENABLE_PIN_ACTIVE_HIGH,
+};
+
+/**
+ * struct smb347_charger_platform_data - platform data for SMB347 charger
+ * @battery_info: Information about the battery
+ * @max_charge_current: maximum current (in uA) the battery can be charged
+ * @max_charge_voltage: maximum voltage (in uV) the battery can be charged
+ * @pre_charge_current: current (in uA) to use in pre-charging phase
+ * @termination_current: current (in uA) used to determine when the
+ *			 charging cycle terminates
+ * @pre_to_fast_voltage: voltage (in uV) treshold used for transitioning to
+ *			 pre-charge to fast charge mode
+ * @mains_current_limit: maximum input current drawn from AC/DC input (in uA)
+ * @usb_hc_current_limit: maximum input high current (in uA) drawn from USB
+ *			  input
+ * @chip_temp_threshold: die temperature where device starts limiting charge
+ *			 current [%100 - %130] (in degree C)
+ * @soft_cold_temp_limit: soft cold temperature limit [%0 - %15] (in degree C),
+ *			  granularity is 5 deg C.
+ * @soft_hot_temp_limit: soft hot temperature limit [%40 - %55] (in degree  C),
+ *			 granularity is 5 deg C.
+ * @hard_cold_temp_limit: hard cold temperature limit [%-5 - %10] (in degree C),
+ *			  granularity is 5 deg C.
+ * @hard_hot_temp_limit: hard hot temperature limit [%50 - %65] (in degree C),
+ *			 granularity is 5 deg C.
+ * @suspend_on_hard_temp_limit: suspend charging when hard limit is hit
+ * @soft_temp_limit_compensation: compensation method when soft temperature
+ *				  limit is hit
+ * @charge_current_compensation: current (in uA) for charging compensation
+ *				 current when temperature hits soft limits
+ * @use_mains: AC/DC input can be used
+ * @use_usb: USB input can be used
+ * @use_usb_otg: USB OTG output can be used (not implemented yet)
+ * @irq_gpio: GPIO number used for interrupts (%-1 if not used)
+ * @enable_control: how charging enable/disable is controlled
+ *		    (driver/pin controls)
+ *
+ * @use_main, @use_usb, and @use_usb_otg are means to enable/disable
+ * hardware support for these. This is useful when we want to have for
+ * example OTG charging controlled via OTG transceiver driver and not by
+ * the SMB347 hardware.
+ *
+ * Hard and soft temperature limit values are given as described in the
+ * device data sheet and assuming NTC beta value is %3750. Even if this is
+ * not the case, these values should be used. They can be mapped to the
+ * corresponding NTC beta values with the help of table %2 in the data
+ * sheet. So for example if NTC beta is %3375 and we want to program hard
+ * hot limit to be %53 deg C, @hard_hot_temp_limit should be set to %50.
+ *
+ * If zero value is given in any of the current and voltage values, the
+ * factory programmed default will be used. For soft/hard temperature
+ * values, pass in %SMB347_TEMP_USE_DEFAULT instead.
+ */
+struct smb347_charger_platform_data {
+	struct power_supply_info battery_info;
+	unsigned int	max_charge_current;
+	unsigned int	max_charge_voltage;
+	unsigned int	pre_charge_current;
+	unsigned int	termination_current;
+	unsigned int	pre_to_fast_voltage;
+	unsigned int	mains_current_limit;
+	unsigned int	usb_hc_current_limit;
+	unsigned int	chip_temp_threshold;
+	int		soft_cold_temp_limit;
+	int		soft_hot_temp_limit;
+	int		hard_cold_temp_limit;
+	int		hard_hot_temp_limit;
+	bool		suspend_on_hard_temp_limit;
+	unsigned int	soft_temp_limit_compensation;
+	unsigned int	charge_current_compensation;
+	bool		use_mains;
+	bool		use_usb;
+	bool		use_usb_otg;
+	int		irq_gpio;
+	enum smb347_chg_enable enable_control;
+};
+
+#endif /* SMB347_CHARGER_H */