/*
 * File:	pci-acpi.c
 * Purpose:	Provide PCI supports in ACPI
 *
 * Copyright (C) 2004 Intel
 * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
 */

#include <linux/delay.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/module.h>
#include <acpi/acpi.h>
#include <acpi/acnamesp.h>
#include <acpi/acresrc.h>
#include <acpi/acpi_bus.h>

#include <linux/pci-acpi.h>

static u32 ctrlset_buf[3] = {0, 0, 0};
static u32 global_ctrlsets = 0;
u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40, 0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};

static acpi_status  
acpi_query_osc (
	acpi_handle	handle,
	u32		level,
	void		*context,
	void		**retval )
{
	acpi_status		status;
	struct acpi_object_list	input;
	union acpi_object 	in_params[4];
	struct acpi_buffer	output;
	union acpi_object 	out_obj;	
	u32			osc_dw0;

	/* Setting up output buffer */
	output.length = sizeof(out_obj) + 3*sizeof(u32);  
	output.pointer = &out_obj;
	
	/* Setting up input parameters */
	input.count = 4;
	input.pointer = in_params;
	in_params[0].type 		= ACPI_TYPE_BUFFER;
	in_params[0].buffer.length 	= 16;
	in_params[0].buffer.pointer	= OSC_UUID;
	in_params[1].type 		= ACPI_TYPE_INTEGER;
	in_params[1].integer.value 	= 1;
	in_params[2].type 		= ACPI_TYPE_INTEGER;
	in_params[2].integer.value	= 3;
	in_params[3].type		= ACPI_TYPE_BUFFER;
	in_params[3].buffer.length 	= 12;
	in_params[3].buffer.pointer 	= (u8 *)context;

	status = acpi_evaluate_object(handle, "_OSC", &input, &output);
	if (ACPI_FAILURE (status)) {
		printk(KERN_DEBUG  
			"Evaluate _OSC Set fails. Status = 0x%04x\n", status);
		return status;
	}
	if (out_obj.type != ACPI_TYPE_BUFFER) {
		printk(KERN_DEBUG  
			"Evaluate _OSC returns wrong type\n");
		return AE_TYPE;
	}
	osc_dw0 = *((u32 *) out_obj.buffer.pointer);
	if (osc_dw0) {
		if (osc_dw0 & OSC_REQUEST_ERROR)
			printk(KERN_DEBUG "_OSC request fails\n"); 
		if (osc_dw0 & OSC_INVALID_UUID_ERROR)
			printk(KERN_DEBUG "_OSC invalid UUID\n"); 
		if (osc_dw0 & OSC_INVALID_REVISION_ERROR)
			printk(KERN_DEBUG "_OSC invalid revision\n"); 
		if (osc_dw0 & OSC_CAPABILITIES_MASK_ERROR) {
			/* Update Global Control Set */
			global_ctrlsets = *((u32 *)(out_obj.buffer.pointer+8));
			return AE_OK;
		}
		return AE_ERROR;
	}

	/* Update Global Control Set */
	global_ctrlsets = *((u32 *)(out_obj.buffer.pointer + 8));
	return AE_OK;
}


static acpi_status  
acpi_run_osc (
	acpi_handle	handle,
	u32		level,
	void		*context,
	void		**retval )
{
	acpi_status		status;
	struct acpi_object_list	input;
	union acpi_object 	in_params[4];
	struct acpi_buffer	output;
	union acpi_object 	out_obj;	
	u32			osc_dw0;

	/* Setting up output buffer */
	output.length = sizeof(out_obj) + 3*sizeof(u32);  
	output.pointer = &out_obj;
	
	/* Setting up input parameters */
	input.count = 4;
	input.pointer = in_params;
	in_params[0].type 		= ACPI_TYPE_BUFFER;
	in_params[0].buffer.length 	= 16;
	in_params[0].buffer.pointer	= OSC_UUID;
	in_params[1].type 		= ACPI_TYPE_INTEGER;
	in_params[1].integer.value 	= 1;
	in_params[2].type 		= ACPI_TYPE_INTEGER;
	in_params[2].integer.value	= 3;
	in_params[3].type		= ACPI_TYPE_BUFFER;
	in_params[3].buffer.length 	= 12;
	in_params[3].buffer.pointer 	= (u8 *)context;

	status = acpi_evaluate_object(handle, "_OSC", &input, &output);
	if (ACPI_FAILURE (status)) {
		printk(KERN_DEBUG  
			"Evaluate _OSC Set fails. Status = 0x%04x\n", status);
		return status;
	}
	if (out_obj.type != ACPI_TYPE_BUFFER) {
		printk(KERN_DEBUG  
			"Evaluate _OSC returns wrong type\n");
		return AE_TYPE;
	}
	osc_dw0 = *((u32 *) out_obj.buffer.pointer);
	if (osc_dw0) {
		if (osc_dw0 & OSC_REQUEST_ERROR)
			printk(KERN_DEBUG "_OSC request fails\n"); 
		if (osc_dw0 & OSC_INVALID_UUID_ERROR)
			printk(KERN_DEBUG "_OSC invalid UUID\n"); 
		if (osc_dw0 & OSC_INVALID_REVISION_ERROR)
			printk(KERN_DEBUG "_OSC invalid revision\n"); 
		if (osc_dw0 & OSC_CAPABILITIES_MASK_ERROR) {
			printk(KERN_DEBUG "_OSC FW not grant req. control\n");
			return AE_SUPPORT;
		}
		return AE_ERROR;
	}
	return AE_OK;
}

/**
 * pci_osc_support_set - register OS support to Firmware
 * @flags: OS support bits
 *
 * Update OS support fields and doing a _OSC Query to obtain an update
 * from Firmware on supported control bits.
 **/
acpi_status pci_osc_support_set(u32 flags)
{
	u32 temp;

	if (!(flags & OSC_SUPPORT_MASKS)) {
		return AE_TYPE;
	}
	ctrlset_buf[OSC_SUPPORT_TYPE] |= (flags & OSC_SUPPORT_MASKS);

	/* do _OSC query for all possible controls */
	temp = ctrlset_buf[OSC_CONTROL_TYPE];
	ctrlset_buf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
	ctrlset_buf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
	acpi_get_devices ( PCI_ROOT_HID_STRING,
			acpi_query_osc,
			ctrlset_buf,
			NULL );
	ctrlset_buf[OSC_QUERY_TYPE] = !OSC_QUERY_ENABLE;
	ctrlset_buf[OSC_CONTROL_TYPE] = temp;
	return AE_OK;
}
EXPORT_SYMBOL(pci_osc_support_set);

/**
 * pci_osc_control_set - commit requested control to Firmware
 * @flags: driver's requested control bits
 *
 * Attempt to take control from Firmware on requested control bits.
 **/
acpi_status pci_osc_control_set(u32 flags)
{
	acpi_status	status;
	u32		ctrlset;

	ctrlset = (flags & OSC_CONTROL_MASKS);
	if (!ctrlset) {
		return AE_TYPE;
	}
	if (ctrlset_buf[OSC_SUPPORT_TYPE] && 
	 	((global_ctrlsets & ctrlset) != ctrlset)) {
		return AE_SUPPORT;
	}
	ctrlset_buf[OSC_CONTROL_TYPE] |= ctrlset;
	status = acpi_get_devices ( PCI_ROOT_HID_STRING,
				acpi_run_osc,
				ctrlset_buf,
				NULL );
	if (ACPI_FAILURE (status)) {
		ctrlset_buf[OSC_CONTROL_TYPE] &= ~ctrlset;
	}
	
	return status;
}
EXPORT_SYMBOL(pci_osc_control_set);