power: Add battery driver for goldfish emulator

Add the emulated power driver for the Goldfish platform.

This folds together the code from the Google tree, Jun Nakajima's cleanups
and x86 porting work, and then a tidy up to pass checkpatch.

Signed-off-by: Mike A. Chan <mikechan@google.com>
[cleanup and x86 support]
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Signed-off-by: Xiaohui Xin <xiaohui.xin@intel.com>
Signed-off-by: Jun Nakajima <jun.nakajima@intel.com>
Signed-off-by: Bruce Beare <bruce.j.beare@intel.com>
[ported to 3.4]
Signed-off-by: Tom Keel <thomas.keel@intel.com>
[ported to 3.7 and final tidy]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Anton Vorontsov <anton@enomsg.org>

drivers/power/Kconfig

@@ -346,6 +346,12 @@ config AB8500_BM
 	help
 	  Say Y to include support for AB8500 battery management.
 
+config BATTERY_GOLDFISH
+	tristate "Goldfish battery driver"
+	help
+	  Say Y to enable support for the battery and AC power in the
+	  Goldfish emulator.
+
 source "drivers/power/reset/Kconfig"
 
 endif # POWER_SUPPLY

drivers/power/Makefile

@@ -20,6 +20,7 @@ obj-$(CONFIG_BATTERY_DS2760)	+= ds2760_battery.o
 obj-$(CONFIG_BATTERY_DS2780)	+= ds2780_battery.o
 obj-$(CONFIG_BATTERY_DS2781)	+= ds2781_battery.o
 obj-$(CONFIG_BATTERY_DS2782)	+= ds2782_battery.o
+obj-$(CONFIG_BATTERY_GOLDFISH)	+= goldfish_battery.o
 obj-$(CONFIG_BATTERY_PMU)	+= pmu_battery.o
 obj-$(CONFIG_BATTERY_OLPC)	+= olpc_battery.o
 obj-$(CONFIG_BATTERY_TOSA)	+= tosa_battery.o

drivers/power/goldfish_battery.c

@@ -0,0 +1,236 @@
+/*
+ * Power supply driver for the goldfish emulator
+ *
+ * Copyright (C) 2008 Google, Inc.
+ * Copyright (C) 2012 Intel, Inc.
+ * Copyright (C) 2013 Intel, Inc.
+ * Author: Mike Lockwood <lockwood@android.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+
+struct goldfish_battery_data {
+	void __iomem *reg_base;
+	int irq;
+	spinlock_t lock;
+
+	struct power_supply battery;
+	struct power_supply ac;
+};
+
+#define GOLDFISH_BATTERY_READ(data, addr) \
+	(readl(data->reg_base + addr))
+#define GOLDFISH_BATTERY_WRITE(data, addr, x) \
+	(writel(x, data->reg_base + addr))
+
+/*
+ * Temporary variable used between goldfish_battery_probe() and
+ * goldfish_battery_open().
+ */
+static struct goldfish_battery_data *battery_data;
+
+enum {
+	/* status register */
+	BATTERY_INT_STATUS	    = 0x00,
+	/* set this to enable IRQ */
+	BATTERY_INT_ENABLE	    = 0x04,
+
+	BATTERY_AC_ONLINE       = 0x08,
+	BATTERY_STATUS          = 0x0C,
+	BATTERY_HEALTH          = 0x10,
+	BATTERY_PRESENT         = 0x14,
+	BATTERY_CAPACITY        = 0x18,
+
+	BATTERY_STATUS_CHANGED	= 1U << 0,
+	AC_STATUS_CHANGED	= 1U << 1,
+	BATTERY_INT_MASK        = BATTERY_STATUS_CHANGED | AC_STATUS_CHANGED,
+};
+
+
+static int goldfish_ac_get_property(struct power_supply *psy,
+			enum power_supply_property psp,
+			union power_supply_propval *val)
+{
+	struct goldfish_battery_data *data = container_of(psy,
+		struct goldfish_battery_data, ac);
+	int ret = 0;
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_ONLINE:
+		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_AC_ONLINE);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	return ret;
+}
+
+static int goldfish_battery_get_property(struct power_supply *psy,
+				 enum power_supply_property psp,
+				 union power_supply_propval *val)
+{
+	struct goldfish_battery_data *data = container_of(psy,
+		struct goldfish_battery_data, battery);
+	int ret = 0;
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_STATUS:
+		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_STATUS);
+		break;
+	case POWER_SUPPLY_PROP_HEALTH:
+		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_HEALTH);
+		break;
+	case POWER_SUPPLY_PROP_PRESENT:
+		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_PRESENT);
+		break;
+	case POWER_SUPPLY_PROP_TECHNOLOGY:
+		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
+		break;
+	case POWER_SUPPLY_PROP_CAPACITY:
+		val->intval = GOLDFISH_BATTERY_READ(data, BATTERY_CAPACITY);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static enum power_supply_property goldfish_battery_props[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_HEALTH,
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_TECHNOLOGY,
+	POWER_SUPPLY_PROP_CAPACITY,
+};
+
+static enum power_supply_property goldfish_ac_props[] = {
+	POWER_SUPPLY_PROP_ONLINE,
+};
+
+static irqreturn_t goldfish_battery_interrupt(int irq, void *dev_id)
+{
+	unsigned long irq_flags;
+	struct goldfish_battery_data *data = dev_id;
+	uint32_t status;
+
+	spin_lock_irqsave(&data->lock, irq_flags);
+
+	/* read status flags, which will clear the interrupt */
+	status = GOLDFISH_BATTERY_READ(data, BATTERY_INT_STATUS);
+	status &= BATTERY_INT_MASK;
+
+	if (status & BATTERY_STATUS_CHANGED)
+		power_supply_changed(&data->battery);
+	if (status & AC_STATUS_CHANGED)
+		power_supply_changed(&data->ac);
+
+	spin_unlock_irqrestore(&data->lock, irq_flags);
+	return status ? IRQ_HANDLED : IRQ_NONE;
+}
+
+
+static int goldfish_battery_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct resource *r;
+	struct goldfish_battery_data *data;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (data == NULL)
+		return -ENOMEM;
+
+	spin_lock_init(&data->lock);
+
+	data->battery.properties = goldfish_battery_props;
+	data->battery.num_properties = ARRAY_SIZE(goldfish_battery_props);
+	data->battery.get_property = goldfish_battery_get_property;
+	data->battery.name = "battery";
+	data->battery.type = POWER_SUPPLY_TYPE_BATTERY;
+
+	data->ac.properties = goldfish_ac_props;
+	data->ac.num_properties = ARRAY_SIZE(goldfish_ac_props);
+	data->ac.get_property = goldfish_ac_get_property;
+	data->ac.name = "ac";
+	data->ac.type = POWER_SUPPLY_TYPE_MAINS;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (r == NULL) {
+		dev_err(&pdev->dev, "platform_get_resource failed\n");
+		return -ENODEV;
+	}
+
+	data->reg_base = devm_ioremap(&pdev->dev, r->start, r->end - r->start + 1);
+	if (data->reg_base == NULL) {
+		dev_err(&pdev->dev, "unable to remap MMIO\n");
+		return -ENOMEM;
+	}
+
+	data->irq = platform_get_irq(pdev, 0);
+	if (data->irq < 0) {
+		dev_err(&pdev->dev, "platform_get_irq failed\n");
+		return -ENODEV;
+	}
+
+	ret = devm_request_irq(&pdev->dev, data->irq, goldfish_battery_interrupt,
+						IRQF_SHARED, pdev->name, data);
+	if (ret)
+		return ret;
+
+	ret = power_supply_register(&pdev->dev, &data->ac);
+	if (ret)
+		return ret;
+
+	ret = power_supply_register(&pdev->dev, &data->battery);
+	if (ret) {
+		power_supply_unregister(&data->ac);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, data);
+	battery_data = data;
+
+	GOLDFISH_BATTERY_WRITE(data, BATTERY_INT_ENABLE, BATTERY_INT_MASK);
+	return 0;
+}
+
+static int goldfish_battery_remove(struct platform_device *pdev)
+{
+	struct goldfish_battery_data *data = platform_get_drvdata(pdev);
+
+	power_supply_unregister(&data->battery);
+	power_supply_unregister(&data->ac);
+	battery_data = NULL;
+	return 0;
+}
+
+static struct platform_driver goldfish_battery_device = {
+	.probe		= goldfish_battery_probe,
+	.remove		= goldfish_battery_remove,
+	.driver = {
+		.name = "goldfish-battery"
+	}
+};
+module_platform_driver(goldfish_battery_device);
+
+MODULE_AUTHOR("Mike Lockwood lockwood@android.com");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Battery driver for the Goldfish emulator");