litmus-rt.git - The LITMUS^RT kernel.

/*
 *  acpi_thermal.c - ACPI Thermal Zone Driver ($Revision: 41 $)
 *
 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  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.
 *
 *  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.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  This driver fully implements the ACPI thermal policy as described in the
 *  ACPI 2.0 Specification.
 *
 *  TBD: 1. Implement passive cooling hysteresis.
 *       2. Enhance passive cooling (CPU) states/limit interface to support
 *          concepts of 'multiple limiters', upper/lower limits, etc.
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/dmi.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/jiffies.h>
#include <linux/kmod.h>
#include <linux/reboot.h>
#include <linux/device.h>
#include <asm/uaccess.h>
#include <linux/thermal.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>

#define PREFIX "ACPI: "

#define ACPI_THERMAL_CLASS		"thermal_zone"
#define ACPI_THERMAL_DEVICE_NAME	"Thermal Zone"
#define ACPI_THERMAL_FILE_STATE		"state"
#define ACPI_THERMAL_FILE_TEMPERATURE	"temperature"
#define ACPI_THERMAL_FILE_TRIP_POINTS	"trip_points"
#define ACPI_THERMAL_FILE_COOLING_MODE	"cooling_mode"
#define ACPI_THERMAL_FILE_POLLING_FREQ	"polling_frequency"
#define ACPI_THERMAL_NOTIFY_TEMPERATURE	0x80
#define ACPI_THERMAL_NOTIFY_THRESHOLDS	0x81
#define ACPI_THERMAL_NOTIFY_DEVICES	0x82
#define ACPI_THERMAL_NOTIFY_CRITICAL	0xF0
#define ACPI_THERMAL_NOTIFY_HOT		0xF1
#define ACPI_THERMAL_MODE_ACTIVE	0x00

#define ACPI_THERMAL_MAX_ACTIVE	10
#define ACPI_THERMAL_MAX_LIMIT_STR_LEN 65

#define _COMPONENT		ACPI_THERMAL_COMPONENT
ACPI_MODULE_NAME("thermal");

MODULE_AUTHOR("Paul Diefenbaugh");
MODULE_DESCRIPTION("ACPI Thermal Zone Driver");
MODULE_LICENSE("GPL");

static int act;
module_param(act, int, 0644);
MODULE_PARM_DESC(act, "Disable or override all lowest active trip points.");

static int crt;
module_param(crt, int, 0644);
MODULE_PARM_DESC(crt, "Disable or lower all critical trip points.");

static int tzp;
module_param(tzp, int, 0444);
MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.");

static int nocrt;
module_param(nocrt, int, 0);
MODULE_PARM_DESC(nocrt, "Set to take no action upon ACPI thermal zone critical trips points.");

static int off;
module_param(off, int, 0);
MODULE_PARM_DESC(off, "Set to disable ACPI thermal support.");

static int psv;
module_param(psv, int, 0644);
MODULE_PARM_DESC(psv, "Disable or override all passive trip points.");

static int acpi_thermal_add(struct acpi_device *device);
static int acpi_thermal_remove(struct acpi_device *device);
static void acpi_thermal_notify(struct acpi_device *device, u32 event);

static const struct acpi_device_id  thermal_device_ids[] = {
	{ACPI_THERMAL_HID, 0},
	{"", 0},
};
MODULE_DEVICE_TABLE(acpi, thermal_device_ids);

#ifdef CONFIG_PM_SLEEP
static int acpi_thermal_resume(struct device *dev);
#endif
static SIMPLE_DEV_PM_OPS(acpi_thermal_pm, NULL, acpi_thermal_resume);

static struct acpi_driver acpi_thermal_driver = {
	.name = "thermal",
	.class = ACPI_THERMAL_CLASS,
	.ids = thermal_device_ids,
	.ops = {
		.add = acpi_thermal_add,
		.remove = acpi_thermal_remove,
		.notify = acpi_thermal_notify,
		},
	.drv.pm = &acpi_thermal_pm,
};

struct acpi_thermal_state {
	u8 critical:1;
	u8 hot:1;
	u8 passive:1;
	u8 active:1;
	u8 reserved:4;
	int active_index;
};

struct acpi_thermal_state_flags {
	u8 valid:1;
	u8 enabled:1;
	u8 reserved:6;
};

struct acpi_thermal_critical {
	struct acpi_thermal_state_flags flags;
	unsigned long temperature;
};

struct acpi_thermal_hot {
	struct acpi_thermal_state_flags flags;
	unsigned long temperature;
};

struct acpi_thermal_passive {
	struct acpi_thermal_state_flags flags;
	unsigned long temperature;
	unsigned long tc1;
	unsigned long tc2;
	unsigned long tsp;
	struct acpi_handle_list devices;
};

struct acpi_thermal_active {
	struct acpi_thermal_state_flags flags;
	unsigned long temperature;
	struct acpi_handle_list devices;
};

struct acpi_thermal_trips {
	struct acpi_thermal_critical critical;
	struct acpi_thermal_hot hot;
	struct acpi_thermal_passive passive;
	struct acpi_thermal_active active[ACPI_THERMAL_MAX_ACTIVE];
};

struct acpi_thermal_flags {
	u8 cooling_mode:1;	/* _SCP */
	u8 devices:1;		/* _TZD */
	u8 reserved:6;
};

struct acpi_thermal {
	struct acpi_device * device;
	acpi_bus_id name;
	unsigned long temperature;
	unsigned long last_temperature;
	unsigned long polling_frequency;
	volatile u8 zombie;
	struct acpi_thermal_flags flags;
	struct acpi_thermal_state state;
	struct acpi_thermal_trips trips;
	struct acpi_handle_list devices;
	struct thermal_zone_device *thermal_zone;
	int tz_enabled;
	int kelvin_offset;
	struct mutex lock;
};

/* --------------------------------------------------------------------------
                             Thermal Zone Management
   -------------------------------------------------------------------------- */

static int acpi_thermal_get_temperature(struct acpi_thermal *tz)
{
	acpi_status status = AE_OK;
	unsigned long long tmp;

	if (!tz)
		return -EINVAL;

	tz->last_temperature = tz->temperature;

	status = acpi_evaluate_integer(tz->device->handle, "_TMP", NULL, &tmp);
	if (ACPI_FAILURE(status))
		return -ENODEV;

	tz->temperature = tmp;
	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Temperature is %lu dK\n",
			  tz->temperature));

	return 0;
}

static int acpi_thermal_get_polling_frequency(struct acpi_thermal *tz)
{
	acpi_status status = AE_OK;
	unsigned long long tmp;

	if (!tz)
		return -EINVAL;

	status = acpi_evaluate_integer(tz->device->handle, "_TZP", NULL, &tmp);
	if (ACPI_FAILURE(status))
		return -ENODEV;

	tz->polling_frequency = tmp;
	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Polling frequency is %lu dS\n",
			  tz->polling_frequency));

	return 0;
}

static int acpi_thermal_set_cooling_mode(struct acpi_thermal *tz, int mode)
{
	acpi_status status = AE_OK;
	union acpi_object arg0 = { ACPI_TYPE_INTEGER };
	struct acpi_object_list arg_list = { 1, &arg0 };
	acpi_handle handle = NULL;


	if (!tz)
		return -EINVAL;

	status = acpi_get_handle(tz->device->handle, "_SCP", &handle);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "_SCP not present\n"));
		return -ENODEV;
	}

	arg0.integer.value = mode;

	status = acpi_evaluate_object(handle, NULL, &arg_list, NULL);
	if (ACPI_FAILURE(status))
		return -ENODEV;

	return 0;
}

#define ACPI_TRIPS_CRITICAL	0x01
#define ACPI_TRIPS_HOT		0x02
#define ACPI_TRIPS_PASSIVE	0x04
#define ACPI_TRIPS_ACTIVE	0x08
#define ACPI_TRIPS_DEVICES	0x10

#define ACPI_TRIPS_REFRESH_THRESHOLDS	(ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE)
#define ACPI_TRIPS_REFRESH_DEVICES	ACPI_TRIPS_DEVICES

#define ACPI_TRIPS_INIT      (ACPI_TRIPS_CRITICAL | ACPI_TRIPS_HOT |	\
			      ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE |	\
			      ACPI_TRIPS_DEVICES)

/*
 * This exception is thrown out in two cases:
 * 1.An invalid trip point becomes invalid or a valid trip point becomes invalid
 *   when re-evaluating the AML code.
 * 2.TODO: Devices listed in _PSL, _ALx, _TZD may change.
 *   We need to re-bind the cooling devices of a thermal zone when this occurs.
 */
#define ACPI_THERMAL_TRIPS_EXCEPTION(flags, str)	\
do {	\
	if (flags != ACPI_TRIPS_INIT)	\
		ACPI_EXCEPTION((AE_INFO, AE_ERROR,	\
		"ACPI thermal trip point %s changed\n"	\
		"Please send acpidump to linux-acpi@vger.kernel.org", str)); \
} while (0)

static int acpi_thermal_trips_update(struct acpi_thermal *tz, int flag)
{
	acpi_status status = AE_OK;
	unsigned long long tmp;
	struct acpi_handle_list devices;
	int valid = 0;
	int i;

	/* Critical Shutdown */
	if (flag & ACPI_TRIPS_CRITICAL) {
		status = acpi_evaluate_integer(tz->device->handle,
				"_CRT", NULL, &tmp);
		tz->trips.critical.temperature = tmp;
		/*
		 * Treat freezing temperatures as invalid as well; some
		 * BIOSes return really low values and cause reboots at startup.
		 * Below zero (Celsius) values clearly aren't right for sure..
		 * ... so lets discard those as invalid.
		 */
		if (ACPI_FAILURE(status)) {
			tz->trips.critical.flags.valid = 0;
			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
					  "No critical threshold\n"));
		} else if (tmp <= 2732) {
			printk(KERN_WARNING FW_BUG "Invalid critical threshold "
			       "(%llu)\n", tmp);
			tz->trips.critical.flags.valid = 0;
		} else {
			tz->trips.critical.flags.valid = 1;
			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
					  "Found critical threshold [%lu]\n",
					  tz->trips.critical.temperature));
		}
		if (tz->trips.critical.flags.valid == 1) {
			if (crt == -1) {
				tz->trips.critical.flags.valid = 0;
			} else if (crt > 0) {
				unsigned long crt_k = CELSIUS_TO_KELVIN(crt);
				/*
				 * Allow override critical threshold
				 */
				if (crt_k > tz->trips.critical.temperature)
					printk(KERN_WARNING PREFIX
						"Critical threshold %d C\n", crt);
				tz->trips.critical.temperature = crt_k;
			}
		}
	}

	/* Critical Sleep (optional) */
	if (flag & ACPI_TRIPS_HOT) {
		status = acpi_evaluate_integer(tz->device->handle,
				"_HOT", NULL, &tmp);
		if (ACPI_FAILURE(status)) {
			tz->trips.hot.flags.valid = 0;
			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
					"No hot threshold\n"));
		} else {
			tz->trips.hot.temperature = tmp;
			tz->trips.hot.flags.valid = 1;
			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
					"Found hot threshold [%lu]\n",
					tz->trips.critical.temperature));
		}
	}

	/* Passive (optional) */
	if (((flag & ACPI_TRIPS_PASSIVE) && tz->trips.passive.flags.valid) ||
		(flag == ACPI_TRIPS_INIT)) {
		valid = tz->trips.passive.flags.valid;
		if (psv == -1) {
			status = AE_SUPPORT;
		} else if (psv > 0) {
			tmp = CELSIUS_TO_KELVIN(psv);
			status = AE_OK;
		} else {
			status = acpi_evaluate_integer(tz->device->handle,
				"_PSV", NULL, &tmp);
		}

		if (ACPI_FAILURE(status))
			tz->trips.passive.flags.valid = 0;
		else {
			tz->trips.passive.temperature = tmp;
			tz->trips.passive.flags.valid = 1;
			if (flag == ACPI_TRIPS_INIT) {
				status = acpi_evaluate_integer(
						tz->device->handle, "_TC1",
						NULL, &tmp);
				if (ACPI_FAILURE(status))
					tz->trips.passive.flags.valid = 0;
				else
					tz->trips.passive.tc1 = tmp;
				status = acpi_evaluate_integer(
						tz->device->handle, "_TC2",
						NULL, &tmp);
				if (ACPI_FAILURE(status))
					tz->trips.passive.flags.valid = 0;
				else
					tz->trips.passive.tc2 = tmp;
				status = acpi_evaluate_integer(
						tz->device->handle, "_TSP",
						NULL, &tmp);
				if (ACPI_FAILURE(status))
					tz->trips.passive.flags.valid = 0;
				else
					tz->trips.passive.tsp = tmp;
			}
		}
	}
	if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.passive.flags.valid) {
		memset(&devices, 0, sizeof(struct acpi_handle_list));
		status = acpi_evaluate_reference(tz->device->handle, "_PSL",
							NULL, &devices);
		if (ACPI_FAILURE(status)) {
			printk(KERN_WARNING PREFIX
				"Invalid passive threshold\n");
			tz->trips.passive.flags.valid = 0;
		}
		else
			tz->trips.passive.flags.valid = 1;

		if (memcmp(&tz->trips.passive.devices, &devices,
				sizeof(struct acpi_handle_list))) {
			memcpy(&tz->trips.passive.devices, &devices,
				sizeof(struct acpi_handle_list));
			ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
		}
	}
	if ((flag & ACPI_TRIPS_PASSIVE) || (flag & ACPI_TRIPS_DEVICES)) {
		if (valid != tz->trips.passive.flags.valid)
				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "state");
	}

	/* Active (optional) */
	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
		char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
		valid = tz->trips.active[i].flags.valid;

		if (act == -1)
			break; /* disable all active trip points */

		if ((flag == ACPI_TRIPS_INIT) || ((flag & ACPI_TRIPS_ACTIVE) &&
			tz->trips.active[i].flags.valid)) {
			status = acpi_evaluate_integer(tz->device->handle,
							name, NULL, &tmp);
			if (ACPI_FAILURE(status)) {
				tz->trips.active[i].flags.valid = 0;
				if (i == 0)
					break;
				if (act <= 0)
					break;
				if (i == 1)
					tz->trips.active[0].temperature =
						CELSIUS_TO_KELVIN(act);
				else
					/*
					 * Don't allow override higher than
					 * the next higher trip point
					 */
					tz->trips.active[i - 1].temperature =
						(tz->trips.active[i - 2].temperature <
						CELSIUS_TO_KELVIN(act) ?
						tz->trips.active[i - 2].temperature :
						CELSIUS_TO_KELVIN(act));
				break;
			} else {
				tz->trips.active[i].temperature = tmp;
				tz->trips.active[i].flags.valid = 1;
			}
		}

		name[2] = 'L';
		if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.active[i].flags.valid ) {
			memset(&devices, 0, sizeof(struct acpi_handle_list));
			status = acpi_evaluate_reference(tz->device->handle,
						name, NULL, &devices);
			if (ACPI_FAILURE(status)) {
				printk(KERN_WARNING PREFIX
					"Invalid active%d threshold\n", i);
				tz->trips.active[i].flags.valid = 0;
			}
			else
				tz->trips.active[i].flags.valid = 1;

			if (memcmp(&tz->trips.active[i].devices, &devices,
					sizeof(struct acpi_handle_list))) {
				memcpy(&tz->trips.active[i].devices, &devices,
					sizeof(struct acpi_handle_list));
				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
			}
		}
		if ((flag & ACPI_TRIPS_ACTIVE) || (flag & ACPI_TRIPS_DEVICES))
			if (valid != tz->trips.active[i].flags.valid)
				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "state");

		if (!tz->trips.active[i].flags.valid)
			break;
	}

	if (flag & ACPI_TRIPS_DEVICES) {
		memset(&devices, 0, sizeof(struct acpi_handle_list));
		status = acpi_evaluate_reference(tz->device->handle, "_TZD",
						NULL, &devices);
		if (memcmp(&tz->devices, &devices,
				sizeof(struct acpi_handle_list))) {
			memcpy(&tz->devices, &devices,
				sizeof(struct acpi_handle_list));
			ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
		}
	}

	return 0;
}

static int acpi_thermal_get_trip_points(struct acpi_thermal *tz)
{
	int i, valid, ret = acpi_thermal_trips_update(tz, ACPI_TRIPS_INIT);

	if (ret)
		return ret;

	valid = tz->trips.critical.flags.valid |
		tz->trips.hot.flags.valid |
		tz->trips.passive.flags.valid;

	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
		valid |= tz->trips.active[i].flags.valid;

	if (!valid) {
		printk(KERN_WARNING FW_BUG "No valid trip found\n");
		return -ENODEV;
	}
	return 0;
}

static void acpi_thermal_check(void *data)
{
	struct acpi_thermal *tz = data;

	if (!tz->tz_enabled) {
		pr_warn("thermal zone is disabled \n");
		return;
	}
	thermal_zone_device_update(tz->thermal_zone);
}

/* sys I/F for generic thermal sysfs support */
#define KELVIN_TO_MILLICELSIUS(t, off) (((t) - (off)) * 100)

static int thermal_get_temp(struct thermal_zone_device *thermal,
			    unsigned long *temp)
{
	struct acpi_thermal *tz = thermal->devdata;
	int result;

	if (!tz)
		return -EINVAL;

	result = acpi_thermal_get_temperature(tz);
	if (result)
		return result;

	*temp = KELVIN_TO_MILLICELSIUS(tz->temperature, tz->kelvin_offset);
	return 0;
}

static int thermal_get_mode(struct thermal_zone_device *thermal,
				enum thermal_device_mode *mode)
{
	struct acpi_thermal *tz = thermal->devdata;

	if (!tz)
		return -EINVAL;

	*mode = tz->tz_enabled ? THERMAL_DEVICE_ENABLED :
		THERMAL_DEVICE_DISABLED;

	return 0;
}

static int thermal_set_mode(struct thermal_zone_device *thermal,
				enum thermal_device_mode mode)
{
	struct acpi_thermal *tz = thermal->devdata;
	int enable;

	if (!tz)
		return -EINVAL;

	/*
	 * enable/disable thermal management from ACPI thermal driver
	 */
	if (mode == THERMAL_DEVICE_ENABLED)
		enable = 1;
	else if (mode == THERMAL_DEVICE_DISABLED)
		enable = 0;
	else
		return -EINVAL;

	if (enable != tz->tz_enabled) {
		tz->tz_enabled = enable;
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
			"%s kernel ACPI thermal control\n",
			tz->tz_enabled ? "Enable" : "Disable"));
		acpi_thermal_check(tz);
	}
	return 0;
}

static int thermal_get_trip_type(struct thermal_zone_device *thermal,
				 int trip, enum thermal_trip_type *type)
{
	struct acpi_thermal *tz = thermal->devdata;
	int i;

	if (!tz || trip < 0)
		return -EINVAL;

	if (tz->trips.critical.flags.valid) {
		if (!trip) {
			*type = THERMAL_TRIP_CRITICAL;
			return 0;
		}
		trip--;
	}

	if (tz->trips.hot.flags.valid) {
		if (!trip) {
			*type = THERMAL_TRIP_HOT;
			return 0;
		}
		trip--;
	}

	if (tz->trips.passive.flags.valid) {
		if (!trip) {
			*type = THERMAL_TRIP_PASSIVE;
			return 0;
		}
		trip--;
	}

	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
		tz->trips.active[i].flags.valid; i++) {
		if (!trip) {
			*type = THERMAL_TRIP_ACTIVE;
			return 0;
		}
		trip--;
	}

	return -EINVAL;
}

static int thermal_get_trip_temp(struct thermal_zone_device *thermal,
				 int trip, unsigned long *temp)
{
	struct acpi_thermal *tz = thermal->devdata;
	int i;

	if (!tz || trip < 0)
		return -EINVAL;

	if (tz->trips.critical.flags.valid) {
		if (!trip) {
			*temp = KELVIN_TO_MILLICELSIUS(
				tz->trips.critical.temperature,
				tz->kelvin_offset);
			return 0;
		}
		trip--;
	}

	if (tz->trips.hot.flags.valid) {
		if (!trip) {
			*temp = KELVIN_TO_MILLICELSIUS(
				tz->trips.hot.temperature,
				tz->kelvin_offset);
			return 0;
		}
		trip--;


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