Skip to main content

Browse the archive

Revision 00250ec90963b7ef6678438888f3244985ecde14 authored by Andre Przywara on 09 April 2012, 22:16:34 UTC, committed by Guenter Roeck on 18 April 2012, 18:15:40 UTC 
hwmon: fam15h_power: fix bogus values with current BIOSes
 
Newer BKDG[1] versions recommend a different initialization value for
the running average range register in the northbridge. This improves
the power reading by avoiding counter saturations resulting in bogus
values for anything below about 80% of TDP power consumption.
Updated BIOSes will have this new value set up from the beginning,
but meanwhile we correct this value ourselves.
This needs to be done on all northbridges, even on those where the
driver itself does not register at.

This fixes the driver on all current machines to provide proper
values for idle load.

[1]
http://support.amd.com/us/Processor_TechDocs/42301_15h_Mod_00h-0Fh_BKDG.pdf
Chapter 3.8: D18F5xE0 Processor TDP Running Average (p. 452)

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
[guenter.roeck@ericsson.com: Removed unnecessary return statement]
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: stable@vger.kernel.org # 3.0+
1 parent e816b57
Raw File
ac97_bus.c 
/*
 * Linux driver model AC97 bus interface
 *
 * Author:	Nicolas Pitre
 * Created:	Jan 14, 2005
 * Copyright:	(C) MontaVista Software Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/string.h>
#include <sound/ac97_codec.h>

/*
 * Let drivers decide whether they want to support given codec from their
 * probe method. Drivers have direct access to the struct snd_ac97
 * structure and may  decide based on the id field amongst other things.
 */
static int ac97_bus_match(struct device *dev, struct device_driver *drv)
{
	return 1;
}

#ifdef CONFIG_PM
static int ac97_bus_suspend(struct device *dev, pm_message_t state)
{
	int ret = 0;

	if (dev->driver && dev->driver->suspend)
		ret = dev->driver->suspend(dev, state);

	return ret;
}

static int ac97_bus_resume(struct device *dev)
{
	int ret = 0;

	if (dev->driver && dev->driver->resume)
		ret = dev->driver->resume(dev);

	return ret;
}
#endif /* CONFIG_PM */

struct bus_type ac97_bus_type = {
	.name		= "ac97",
	.match		= ac97_bus_match,
#ifdef CONFIG_PM
	.suspend	= ac97_bus_suspend,
	.resume		= ac97_bus_resume,
#endif /* CONFIG_PM */
};

static int __init ac97_bus_init(void)
{
	return bus_register(&ac97_bus_type);
}

subsys_initcall(ac97_bus_init);

static void __exit ac97_bus_exit(void)
{
	bus_unregister(&ac97_bus_type);
}

module_exit(ac97_bus_exit);

EXPORT_SYMBOL(ac97_bus_type);

MODULE_LICENSE("GPL");
back to top