Merge branch 'vexpress-drivers' of git://git.linaro.org/people/pawelmoll/linux into next/drivers

Versatile Express hwmon sensors

-------------------------------

Requires node properties:

- "compatible" value : one of

	"arm,vexpress-volt"

	"arm,vexpress-amp"

	"arm,vexpress-temp"

	"arm,vexpress-power"

	"arm,vexpress-energy"

- "arm,vexpress-sysreg,func" when controlled via vexpress-sysreg

  (see Documentation/devicetree/bindings/arm/vexpress-sysreg.txt

  for more details)

Optional node properties:

- label : string describing the monitored value

Example:

	energy@0 {

		compatible = "arm,vexpress-energy";

		arm,vexpress-sysreg,func = <13 0>;

		label = "A15 Jcore";

	};

Kernel driver vexpress

======================

Supported systems:

  * ARM Ltd. Versatile Express platform

    Prefix: 'vexpress'

    Datasheets:

      * "Hardware Description" sections of the Technical Reference Manuals

        for the Versatile Express boards:

        http://infocenter.arm.com/help/topic/com.arm.doc.subset.boards.express/index.html

      * Section "4.4.14. System Configuration registers" of the V2M-P1 TRM:

        http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0447-/index.html

Author: Pawel Moll

Description

-----------

Versatile Express platform (http://www.arm.com/versatileexpress/) is a

reference & prototyping system for ARM Ltd. processors. It can be set up

from a wide range of boards, each of them containing (apart of the main

chip/FPGA) a number of microcontrollers responsible for platform

configuration and control. Theses microcontrollers can also monitor the

board and its environment by a number of internal and external sensors,

providing information about power lines voltages and currents, board

temperature and power usage. Some of them also calculate consumed energy

and provide a cumulative use counter.

The configuration devices are _not_ memory mapped and must be accessed

via a custom interface, abstracted by the "vexpress_config" API.

As these devices are non-discoverable, they must be described in a Device

Tree passed to the kernel. Details of the DT binding for them can be found

in Documentation/devicetree/bindings/hwmon/vexpress.txt.

/*

 * 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.

 *

 * 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.

 *

 * Copyright (C) 2012 ARM Limited

 */

#include <linux/jiffies.h>

#include <linux/of.h>

#include <linux/of_device.h>

#include <linux/platform_device.h>

#include <linux/stat.h>

#include <linux/vexpress.h>

static void vexpress_reset_do(struct device *dev, const char *what)

{

	int err = -ENOENT;

	struct vexpress_config_func *func =

			vexpress_config_func_get_by_dev(dev);

	if (func) {

		unsigned long timeout;

		err = vexpress_config_write(func, 0, 0);

		timeout = jiffies + HZ;

		while (time_before(jiffies, timeout))

			cpu_relax();

	}

	dev_emerg(dev, "Unable to %s (%d)\n", what, err);

}

static struct device *vexpress_power_off_device;

void vexpress_power_off(void)

{

	vexpress_reset_do(vexpress_power_off_device, "power off");

}

static struct device *vexpress_restart_device;

void vexpress_restart(char str, const char *cmd)

{

	vexpress_reset_do(vexpress_restart_device, "restart");

}

static ssize_t vexpress_reset_active_show(struct device *dev,

		struct device_attribute *attr, char *buf)

{

	return sprintf(buf, "%d\n", vexpress_restart_device == dev);

}

static ssize_t vexpress_reset_active_store(struct device *dev,

		struct device_attribute *attr, const char *buf, size_t count)

{

	long value;

	int err = kstrtol(buf, 0, &value);

	if (!err && value)

		vexpress_restart_device = dev;

	return err ? err : count;

}

DEVICE_ATTR(active, S_IRUGO | S_IWUSR, vexpress_reset_active_show,

		vexpress_reset_active_store);

enum vexpress_reset_func { FUNC_RESET, FUNC_SHUTDOWN, FUNC_REBOOT };

static struct of_device_id vexpress_reset_of_match[] = {

	{

		.compatible = "arm,vexpress-reset",

		.data = (void *)FUNC_RESET,

	}, {

		.compatible = "arm,vexpress-shutdown",

		.data = (void *)FUNC_SHUTDOWN

	}, {

		.compatible = "arm,vexpress-reboot",

		.data = (void *)FUNC_REBOOT

	},

	{}

};

static int vexpress_reset_probe(struct platform_device *pdev)

{

	enum vexpress_reset_func func;

	const struct of_device_id *match =

			of_match_device(vexpress_reset_of_match, &pdev->dev);

	if (match)

		func = (enum vexpress_reset_func)match->data;

	else

		func = pdev->id_entry->driver_data;

	switch (func) {

	case FUNC_SHUTDOWN:

		vexpress_power_off_device = &pdev->dev;

		break;

	case FUNC_RESET:

		if (!vexpress_restart_device)

			vexpress_restart_device = &pdev->dev;

		device_create_file(&pdev->dev, &dev_attr_active);

		break;

	case FUNC_REBOOT:

		vexpress_restart_device = &pdev->dev;

		device_create_file(&pdev->dev, &dev_attr_active);

		break;

	};

	return 0;

}

static const struct platform_device_id vexpress_reset_id_table[] = {

	{ .name = "vexpress-reset", .driver_data = FUNC_RESET, },

	{ .name = "vexpress-shutdown", .driver_data = FUNC_SHUTDOWN, },

	{ .name = "vexpress-reboot", .driver_data = FUNC_REBOOT, },

	{}

};

static struct platform_driver vexpress_reset_driver = {

	.probe = vexpress_reset_probe,

	.driver = {

		.name = "vexpress-reset",

		.of_match_table = vexpress_reset_of_match,

	},

	.id_table = vexpress_reset_id_table,

};

static int __init vexpress_reset_init(void)

{

	return platform_driver_register(&vexpress_reset_driver);

}

device_initcall(vexpress_reset_init);

	This driver can also be built as a module. If so it will be called

	twl4030-madc-hwmon.

config SENSORS_VEXPRESS

	tristate "Versatile Express"

	depends on VEXPRESS_CONFIG

	help

	  This driver provides support for hardware sensors available on

	  the ARM Ltd's Versatile Express platform. It can provide wide

	  range of information like temperature, power, energy.

config SENSORS_VIA_CPUTEMP

	tristate "VIA CPU temperature sensor"

	depends on X86

obj-$(CONFIG_SENSORS_TMP401)	+= tmp401.o

obj-$(CONFIG_SENSORS_TMP421)	+= tmp421.o

obj-$(CONFIG_SENSORS_TWL4030_MADC)+= twl4030-madc-hwmon.o

obj-$(CONFIG_SENSORS_VEXPRESS)	+= vexpress.o

obj-$(CONFIG_SENSORS_VIA_CPUTEMP)+= via-cputemp.o

obj-$(CONFIG_SENSORS_VIA686A)	+= via686a.o

obj-$(CONFIG_SENSORS_VT1211)	+= vt1211.o