bmpower.c

一个2.4.21版本的嵌入式linux内核

/****************************************************************************
 *
 * Module Name: bmpower.c - Driver for ACPI Power Resource 'devices'
 *   $Revision: 20 $
 *
 ****************************************************************************/

/*
 *  Copyright (C) 2000, 2001 Andrew Grover
 *
 *  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
 */

/*
 * TBD: 1. Sequencing of power resource list transitions.
 *	2. Global serialization of power resource transtions (see ACPI
 *         spec section 7.1.2/7.1.3).
 *      3. Better error handling.
 */


#include <acpi.h>
#include "bm.h"
#include "bmpower.h"


#define _COMPONENT		ACPI_BUS
	MODULE_NAME		("bmpower")


/****************************************************************************
 *                             Function Prototypes
 ****************************************************************************/

acpi_status
bm_pr_notify (
	BM_NOTIFY               notify_type,
	BM_HANDLE               device_handle,
	void                    **context);
	
acpi_status
bm_pr_request (
	BM_REQUEST		*request,
	void                    *context);

	
/****************************************************************************
 *                             Internal Functions
 ****************************************************************************/

/****************************************************************************
 *
 * FUNCTION:    bm_pr_print
 *
 * PARAMETERS:
 *
 * RETURN:
 *
 * DESCRIPTION:
 *
 ****************************************************************************/

acpi_status
bm_pr_print (
	BM_POWER_RESOURCE	*pr)
{
	acpi_buffer             buffer;

	PROC_NAME("bm_pr_print");

	if (!pr) {
		return(AE_BAD_PARAMETER);
	}

	buffer.length = 256;
	buffer.pointer = acpi_os_callocate(buffer.length);
	if (!buffer.pointer) {
		return(AE_NO_MEMORY);
	}

	acpi_get_name(pr->acpi_handle, ACPI_FULL_PATHNAME, &buffer);

	acpi_os_printf("Power Resource: found\n");

	ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INFO, "+------------------------------------------------------------\n"));
	ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INFO, "| Power_resource[%02x]:[%p] %s\n", pr->device_handle, pr->acpi_handle, (char*)buffer.pointer));
	ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INFO, "|   system_level[S%d] resource_order[%d]\n", pr->system_level, pr->resource_order));
	ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INFO, "|   state[D%d] reference_count[%d]\n", pr->state, pr->reference_count));
	ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INFO, "+------------------------------------------------------------\n"));

	acpi_os_free(buffer.pointer);

	return(AE_OK);
}


/****************************************************************************
 *
 * FUNCTION:    bm_pr_get_state
 *
 * PARAMETERS:
 *
 * RETURN:
 *
 * DESCRIPTION:
 *
 ****************************************************************************/

acpi_status
bm_pr_get_state (
	BM_POWER_RESOURCE	*pr)
{
	acpi_status             status = AE_OK;
	BM_DEVICE_STATUS        device_status = BM_STATUS_UNKNOWN;

	FUNCTION_TRACE("bm_pr_get_state");

	if (!pr) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	pr->state = ACPI_STATE_UNKNOWN;

	/*
	 * Evaluate _STA:
	 * --------------
	 * Evalute _STA to determine whether the power resource is ON or OFF.
	 * Note that if the power resource isn't present we'll get AE_OK but
	 * an unknown status.
	 */
	status = bm_get_device_status(pr->device_handle, &device_status);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Error reading status for power resource [%02x].\n", pr->device_handle));
		return_ACPI_STATUS(status);
	}

	/*
	 * Mask off all bits but the first as some systems return non-standard
	 * values (e.g. 0x51).
	 */
	switch (device_status & 0x01) {
	case 0:
		ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "Power resource [%02x] is OFF.\n", pr->device_handle));
		pr->state = ACPI_STATE_D3;
		break;
	case 1:
		ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "Power resource [%02x] is ON.\n", pr->device_handle));
		pr->state = ACPI_STATE_D0;
		break;
	}

	return_ACPI_STATUS(status);
}


/****************************************************************************
 *
 * FUNCTION:    bm_pr_set_state
 *
 * PARAMETERS:
 *
 * RETURN:
 *
 * DESCRIPTION:
 *
 ****************************************************************************/

acpi_status
bm_pr_set_state (
	BM_POWER_RESOURCE	*pr,
	BM_POWER_STATE          target_state)
{
	acpi_status             status = AE_OK;

	FUNCTION_TRACE("bm_pr_set_state");

	if (!pr) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	status = bm_pr_get_state(pr);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	if (target_state == pr->state) {
		ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "Power resource [%02x] already at target power state [D%d].\n", pr->device_handle, pr->state));
		return_ACPI_STATUS(AE_OK);
	}

	switch (target_state) {

	case ACPI_STATE_D0:
		ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "Turning power resource [%02x] ON.\n", pr->device_handle));
		status = bm_evaluate_object(pr->acpi_handle, "_ON", NULL, NULL);
		break;

	case ACPI_STATE_D3:
		ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "Turning power resource [%02x] OFF.\n", pr->device_handle));
		status = bm_evaluate_object(pr->acpi_handle, "_OFF", NULL, NULL);
		break;

	default:
		status = AE_BAD_PARAMETER;
		break;
	}

	status = bm_pr_get_state(pr);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	return_ACPI_STATUS(status);
}


/****************************************************************************
 *
 * FUNCTION:    bm_pr_list_get_state
 *
 * PARAMETERS:
 *
 * RETURN:
 *
 * DESCRIPTION:
 *
 ****************************************************************************/

acpi_status
bm_pr_list_get_state (
	BM_HANDLE_LIST          *pr_list,
	BM_POWER_STATE          *power_state)
{
	acpi_status             status = AE_OK;
	BM_POWER_RESOURCE	*pr = NULL;
	u32                     i = 0;

	FUNCTION_TRACE("bm_pr_list_get_state");

	if (!pr_list || !power_state) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	if (pr_list->count < 1) {
		pr->state = ACPI_STATE_UNKNOWN;
		return_ACPI_STATUS(AE_ERROR);
	}

	(*power_state) = ACPI_STATE_D0;

	/*
	 * Calculate Current power_state:
	 * -----------------------------
	 * The current state of a list of power resources is ON if all
	 * power resources are currently in the ON state.  In other words,
	 * if any power resource in the list is OFF then the collection
	 * isn't fully ON.
	 */
	for (i = 0; i < pr_list->count; i++) {

		status = bm_get_device_context(pr_list->handles[i],
			(BM_DRIVER_CONTEXT*)(&pr));
		if (ACPI_FAILURE(status)) {
			ACPI_DEBUG_PRINT ((ACPI_DB_WARN, "Invalid reference to power resource [%02x].\n", pr_list->handles[i]));
			(*power_state) = ACPI_STATE_UNKNOWN;
			break;
		}

		status = bm_pr_get_state(pr);
		if (ACPI_FAILURE(status)) {
			(*power_state) = ACPI_STATE_UNKNOWN;
			break;
		}

		if (pr->state != ACPI_STATE_D0) {
			(*power_state) = pr->state;
			break;
		}
	}

	return_ACPI_STATUS(status);
}


/****************************************************************************
 *
 * FUNCTION:    bm_pr_list_transition
 *
 * PARAMETERS:
 *
 * RETURN:
 *
 * DESCRIPTION:
 *
 ****************************************************************************/

acpi_status
bm_pr_list_transition (
	BM_HANDLE_LIST          *current_list,
	BM_HANDLE_LIST          *target_list)
{
	acpi_status             status = AE_OK;
	BM_POWER_RESOURCE	*pr = NULL;
	u32                     i = 0;

	FUNCTION_TRACE("bm_pr_list_transition");

	if (!current_list || !target_list) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	/*
	 * Reference Target:
	 * -----------------
	 * Reference all resources for the target power state first (so
	 * the device doesn't get turned off while transitioning).  Power
	 * resources that aren't on (new reference count of 1) are turned on.
	 */
	for (i = 0; i < target_list->count; i++) {

		status = bm_get_device_context(target_list->handles[i],