Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 835 insertions, 0 deletions

diff --git a/drivers/acpi/executer/exfldio.c b/drivers/acpi/executer/exfldio.c
new file mode 100644
index 000000000000..9d0f9d2e9061
--- /dev/null
+++ b/drivers/acpi/executer/exfldio.c
@@ -0,0 +1,835 @@
+/******************************************************************************
+ *
+ * Module Name: exfldio - Aml Field I/O
+ *
+ *****************************************************************************/
+
+/*
+ * Copyright (C) 2000 - 2005, R. Byron Moore
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce at minimum a disclaimer
+ *    substantially similar to the "NO WARRANTY" disclaimer below
+ *    ("Disclaimer") and any redistribution must be conditioned upon
+ *    including a substantially similar Disclaimer requirement for further
+ *    binary redistribution.
+ * 3. Neither the names of the above-listed copyright holders nor the names
+ *    of any contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * NO WARRANTY
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGES.
+ */
+
+
+#include <acpi/acpi.h>
+#include <acpi/acinterp.h>
+#include <acpi/amlcode.h>
+#include <acpi/acevents.h>
+#include <acpi/acdispat.h>
+
+
+#define _COMPONENT          ACPI_EXECUTER
+	 ACPI_MODULE_NAME    ("exfldio")
+
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_setup_region
+ *
+ * PARAMETERS:  *obj_desc               - Field to be read or written
+ *              field_datum_byte_offset - Byte offset of this datum within the
+ *                                        parent field
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Common processing for acpi_ex_extract_from_field and
+ *              acpi_ex_insert_into_field. Initialize the Region if necessary and
+ *              validate the request.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ex_setup_region (
+	union acpi_operand_object       *obj_desc,
+	u32                             field_datum_byte_offset)
+{
+	acpi_status                     status = AE_OK;
+	union acpi_operand_object       *rgn_desc;
+
+
+	ACPI_FUNCTION_TRACE_U32 ("ex_setup_region", field_datum_byte_offset);
+
+
+	rgn_desc = obj_desc->common_field.region_obj;
+
+	/* We must have a valid region */
+
+	if (ACPI_GET_OBJECT_TYPE (rgn_desc) != ACPI_TYPE_REGION) {
+		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Needed Region, found type %X (%s)\n",
+			ACPI_GET_OBJECT_TYPE (rgn_desc),
+			acpi_ut_get_object_type_name (rgn_desc)));
+
+		return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
+	}
+
+	/*
+	 * If the Region Address and Length have not been previously evaluated,
+	 * evaluate them now and save the results.
+	 */
+	if (!(rgn_desc->common.flags & AOPOBJ_DATA_VALID)) {
+		status = acpi_ds_get_region_arguments (rgn_desc);
+		if (ACPI_FAILURE (status)) {
+			return_ACPI_STATUS (status);
+		}
+	}
+
+	if (rgn_desc->region.space_id == ACPI_ADR_SPACE_SMBUS) {
+		/* SMBus has a non-linear address space */
+
+		return_ACPI_STATUS (AE_OK);
+	}
+
+#ifdef ACPI_UNDER_DEVELOPMENT
+	/*
+	 * If the Field access is any_acc, we can now compute the optimal
+	 * access (because we know know the length of the parent region)
+	 */
+	if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
+		if (ACPI_FAILURE (status)) {
+			return_ACPI_STATUS (status);
+		}
+	}
+#endif
+
+	/*
+	 * Validate the request.  The entire request from the byte offset for a
+	 * length of one field datum (access width) must fit within the region.
+	 * (Region length is specified in bytes)
+	 */
+	if (rgn_desc->region.length < (obj_desc->common_field.base_byte_offset
+			   + field_datum_byte_offset
+			   + obj_desc->common_field.access_byte_width)) {
+		if (acpi_gbl_enable_interpreter_slack) {
+			/*
+			 * Slack mode only:  We will go ahead and allow access to this
+			 * field if it is within the region length rounded up to the next
+			 * access width boundary.
+			 */
+			if (ACPI_ROUND_UP (rgn_desc->region.length,
+					   obj_desc->common_field.access_byte_width) >=
+				(obj_desc->common_field.base_byte_offset +
+				 (acpi_native_uint) obj_desc->common_field.access_byte_width +
+				 field_datum_byte_offset)) {
+				return_ACPI_STATUS (AE_OK);
+			}
+		}
+
+		if (rgn_desc->region.length < obj_desc->common_field.access_byte_width) {
+			/*
+			 * This is the case where the access_type (acc_word, etc.) is wider
+			 * than the region itself.  For example, a region of length one
+			 * byte, and a field with Dword access specified.
+			 */
+			ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
+				"Field [%4.4s] access width (%d bytes) too large for region [%4.4s] (length %X)\n",
+				acpi_ut_get_node_name (obj_desc->common_field.node),
+				obj_desc->common_field.access_byte_width,
+				acpi_ut_get_node_name (rgn_desc->region.node), rgn_desc->region.length));
+		}
+
+		/*
+		 * Offset rounded up to next multiple of field width
+		 * exceeds region length, indicate an error
+		 */
+		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
+			"Field [%4.4s] Base+Offset+Width %X+%X+%X is beyond end of region [%4.4s] (length %X)\n",
+			acpi_ut_get_node_name (obj_desc->common_field.node),
+			obj_desc->common_field.base_byte_offset,
+			field_datum_byte_offset, obj_desc->common_field.access_byte_width,
+			acpi_ut_get_node_name (rgn_desc->region.node), rgn_desc->region.length));
+
+		return_ACPI_STATUS (AE_AML_REGION_LIMIT);
+	}
+
+	return_ACPI_STATUS (AE_OK);
+}
+
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_access_region
+ *
+ * PARAMETERS:  *obj_desc               - Field to be read
+ *              field_datum_byte_offset - Byte offset of this datum within the
+ *                                        parent field
+ *              *Value                  - Where to store value (must at least
+ *                                        the size of acpi_integer)
+ *              Function                - Read or Write flag plus other region-
+ *                                        dependent flags
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Read or Write a single field datum to an Operation Region.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ex_access_region (
+	union acpi_operand_object       *obj_desc,
+	u32                             field_datum_byte_offset,
+	acpi_integer                    *value,
+	u32                             function)
+{
+	acpi_status                     status;
+	union acpi_operand_object       *rgn_desc;
+	acpi_physical_address           address;
+
+
+	ACPI_FUNCTION_TRACE ("ex_access_region");
+
+
+	/*
+	 * Ensure that the region operands are fully evaluated and verify
+	 * the validity of the request
+	 */
+	status = acpi_ex_setup_region (obj_desc, field_datum_byte_offset);
+	if (ACPI_FAILURE (status)) {
+		return_ACPI_STATUS (status);
+	}
+
+	/*
+	 * The physical address of this field datum is:
+	 *
+	 * 1) The base of the region, plus
+	 * 2) The base offset of the field, plus
+	 * 3) The current offset into the field
+	 */
+	rgn_desc = obj_desc->common_field.region_obj;
+	address = rgn_desc->region.address
+			 + obj_desc->common_field.base_byte_offset
+			 + field_datum_byte_offset;
+
+	if ((function & ACPI_IO_MASK) == ACPI_READ) {
+		ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "[READ]"));
+	}
+	else {
+		ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "[WRITE]"));
+	}
+
+	ACPI_DEBUG_PRINT_RAW ((ACPI_DB_BFIELD,
+		" Region [%s:%X], Width %X, byte_base %X, Offset %X at %8.8X%8.8X\n",
+		acpi_ut_get_region_name (rgn_desc->region.space_id),
+		rgn_desc->region.space_id,
+		obj_desc->common_field.access_byte_width,
+		obj_desc->common_field.base_byte_offset,
+		field_datum_byte_offset,
+		ACPI_FORMAT_UINT64 (address)));
+
+	/* Invoke the appropriate address_space/op_region handler */
+
+	status = acpi_ev_address_space_dispatch (rgn_desc, function,
+			  address, ACPI_MUL_8 (obj_desc->common_field.access_byte_width), value);
+
+	if (ACPI_FAILURE (status)) {
+		if (status == AE_NOT_IMPLEMENTED) {
+			ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
+				"Region %s(%X) not implemented\n",
+				acpi_ut_get_region_name (rgn_desc->region.space_id),
+				rgn_desc->region.space_id));
+		}
+		else if (status == AE_NOT_EXIST) {
+			ACPI_REPORT_ERROR ((
+				"Region %s(%X) has no handler\n",
+				acpi_ut_get_region_name (rgn_desc->region.space_id),
+				rgn_desc->region.space_id));
+		}
+	}
+
+	return_ACPI_STATUS (status);
+}
+
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_register_overflow
+ *
+ * PARAMETERS:  *obj_desc               - Register(Field) to be written
+ *              Value                   - Value to be stored
+ *
+ * RETURN:      TRUE if value overflows the field, FALSE otherwise
+ *
+ * DESCRIPTION: Check if a value is out of range of the field being written.
+ *              Used to check if the values written to Index and Bank registers
+ *              are out of range.  Normally, the value is simply truncated
+ *              to fit the field, but this case is most likely a serious
+ *              coding error in the ASL.
+ *
+ ******************************************************************************/
+
+u8
+acpi_ex_register_overflow (
+	union acpi_operand_object       *obj_desc,
+	acpi_integer                    value)
+{
+
+	if (obj_desc->common_field.bit_length >= ACPI_INTEGER_BIT_SIZE) {
+		/*
+		 * The field is large enough to hold the maximum integer, so we can
+		 * never overflow it.
+		 */
+		return (FALSE);
+	}
+
+	if (value >= ((acpi_integer) 1 << obj_desc->common_field.bit_length)) {
+		/*
+		 * The Value is larger than the maximum value that can fit into
+		 * the register.
+		 */
+		return (TRUE);
+	}
+
+	/* The Value will fit into the field with no truncation */
+
+	return (FALSE);
+}
+
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_field_datum_io
+ *
+ * PARAMETERS:  *obj_desc               - Field to be read
+ *              field_datum_byte_offset - Byte offset of this datum within the
+ *                                        parent field
+ *              *Value                  - Where to store value (must be 64 bits)
+ *              read_write              - Read or Write flag
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Read or Write a single datum of a field.  The field_type is
+ *              demultiplexed here to handle the different types of fields
+ *              (buffer_field, region_field, index_field, bank_field)
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ex_field_datum_io (
+	union acpi_operand_object       *obj_desc,
+	u32                             field_datum_byte_offset,
+	acpi_integer                    *value,
+	u32                             read_write)
+{
+	acpi_status                     status;
+	acpi_integer                    local_value;
+
+
+	ACPI_FUNCTION_TRACE_U32 ("ex_field_datum_io", field_datum_byte_offset);
+
+
+	if (read_write == ACPI_READ) {
+		if (!value) {
+			local_value = 0;
+			value = &local_value; /* To support reads without saving return value */
+		}
+
+		/* Clear the entire return buffer first, [Very Important!] */
+
+		*value = 0;
+	}
+
+	/*
+	 * The four types of fields are:
+	 *
+	 * buffer_field - Read/write from/to a Buffer
+	 * region_field - Read/write from/to a Operation Region.
+	 * bank_field  - Write to a Bank Register, then read/write from/to an op_region
+	 * index_field - Write to an Index Register, then read/write from/to a Data Register
+	 */
+	switch (ACPI_GET_OBJECT_TYPE (obj_desc)) {
+	case ACPI_TYPE_BUFFER_FIELD:
+		/*
+		 * If the buffer_field arguments have not been previously evaluated,
+		 * evaluate them now and save the results.
+		 */
+		if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
+			status = acpi_ds_get_buffer_field_arguments (obj_desc);
+			if (ACPI_FAILURE (status)) {
+				return_ACPI_STATUS (status);
+			}
+		}
+
+		if (read_write == ACPI_READ) {
+			/*
+			 * Copy the data from the source buffer.
+			 * Length is the field width in bytes.
+			 */
+			ACPI_MEMCPY (value, (obj_desc->buffer_field.buffer_obj)->buffer.pointer
+					  + obj_desc->buffer_field.base_byte_offset
+					  + field_datum_byte_offset,
+					  obj_desc->common_field.access_byte_width);
+		}
+		else {
+			/*
+			 * Copy the data to the target buffer.
+			 * Length is the field width in bytes.
+			 */
+			ACPI_MEMCPY ((obj_desc->buffer_field.buffer_obj)->buffer.pointer
+					+ obj_desc->buffer_field.base_byte_offset
+					+ field_datum_byte_offset,
+					value, obj_desc->common_field.access_byte_width);
+		}
+
+		status = AE_OK;
+		break;
+
+
+	case ACPI_TYPE_LOCAL_BANK_FIELD:
+
+		/* Ensure that the bank_value is not beyond the capacity of the register */
+
+		if (acpi_ex_register_overflow (obj_desc->bank_field.bank_obj,
+				  (acpi_integer) obj_desc->bank_field.value)) {
+			return_ACPI_STATUS (AE_AML_REGISTER_LIMIT);
+		}
+
+		/*
+		 * For bank_fields, we must write the bank_value to the bank_register
+		 * (itself a region_field) before we can access the data.
+		 */
+		status = acpi_ex_insert_into_field (obj_desc->bank_field.bank_obj,
+				 &obj_desc->bank_field.value,
+				 sizeof (obj_desc->bank_field.value));
+		if (ACPI_FAILURE (status)) {
+			return_ACPI_STATUS (status);
+		}
+
+		/*
+		 * Now that the Bank has been selected, fall through to the
+		 * region_field case and write the datum to the Operation Region
+		 */
+
+		/*lint -fallthrough */
+
+
+	case ACPI_TYPE_LOCAL_REGION_FIELD:
+		/*
+		 * For simple region_fields, we just directly access the owning
+		 * Operation Region.
+		 */
+		status = acpi_ex_access_region (obj_desc, field_datum_byte_offset, value,
+				  read_write);
+		break;
+
+
+	case ACPI_TYPE_LOCAL_INDEX_FIELD:
+
+
+		/* Ensure that the index_value is not beyond the capacity of the register */
+
+		if (acpi_ex_register_overflow (obj_desc->index_field.index_obj,
+				  (acpi_integer) obj_desc->index_field.value)) {
+			return_ACPI_STATUS (AE_AML_REGISTER_LIMIT);
+		}
+
+		/* Write the index value to the index_register (itself a region_field) */
+
+		field_datum_byte_offset += obj_desc->index_field.value;
+
+		ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
+				"Write to Index Register: Value %8.8X\n",
+				field_datum_byte_offset));
+
+		status = acpi_ex_insert_into_field (obj_desc->index_field.index_obj,
+				 &field_datum_byte_offset,
+				 sizeof (field_datum_byte_offset));
+		if (ACPI_FAILURE (status)) {
+			return_ACPI_STATUS (status);
+		}
+
+		ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
+				"I/O to Data Register: value_ptr %p\n",
+				value));
+
+		if (read_write == ACPI_READ) {
+			/* Read the datum from the data_register */
+
+			status = acpi_ex_extract_from_field (obj_desc->index_field.data_obj,
+					  value, sizeof (acpi_integer));
+		}
+		else {
+			/* Write the datum to the data_register */
+
+			status = acpi_ex_insert_into_field (obj_desc->index_field.data_obj,
+					  value, sizeof (acpi_integer));
+		}
+		break;
+
+
+	default:
+
+		ACPI_REPORT_ERROR (("Wrong object type in field I/O %X\n",
+			ACPI_GET_OBJECT_TYPE (obj_desc)));
+		status = AE_AML_INTERNAL;
+		break;
+	}
+
+	if (ACPI_SUCCESS (status)) {
+		if (read_write == ACPI_READ) {
+			ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Value Read %8.8X%8.8X, Width %d\n",
+					   ACPI_FORMAT_UINT64 (*value),
+					   obj_desc->common_field.access_byte_width));
+		}
+		else {
+			ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Value Written %8.8X%8.8X, Width %d\n",
+					   ACPI_FORMAT_UINT64 (*value),
+					   obj_desc->common_field.access_byte_width));
+		}
+	}
+
+	return_ACPI_STATUS (status);
+}
+
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_write_with_update_rule
+ *
+ * PARAMETERS:  *obj_desc           - Field to be set
+ *              Value               - Value to store
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Apply the field update rule to a field write
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ex_write_with_update_rule (
+	union acpi_operand_object       *obj_desc,
+	acpi_integer                    mask,
+	acpi_integer                    field_value,
+	u32                             field_datum_byte_offset)
+{
+	acpi_status                     status = AE_OK;
+	acpi_integer                    merged_value;
+	acpi_integer                    current_value;
+
+
+	ACPI_FUNCTION_TRACE_U32 ("ex_write_with_update_rule", mask);
+
+
+	/* Start with the new bits  */
+
+	merged_value = field_value;
+
+	/* If the mask is all ones, we don't need to worry about the update rule */
+
+	if (mask != ACPI_INTEGER_MAX) {
+		/* Decode the update rule */
+
+		switch (obj_desc->common_field.field_flags & AML_FIELD_UPDATE_RULE_MASK) {
+		case AML_FIELD_UPDATE_PRESERVE:
+			/*
+			 * Check if update rule needs to be applied (not if mask is all
+			 * ones)  The left shift drops the bits we want to ignore.
+			 */
+			if ((~mask << (ACPI_MUL_8 (sizeof (mask)) -
+					 ACPI_MUL_8 (obj_desc->common_field.access_byte_width))) != 0) {
+				/*
+				 * Read the current contents of the byte/word/dword containing
+				 * the field, and merge with the new field value.
+				 */
+				status = acpi_ex_field_datum_io (obj_desc, field_datum_byte_offset,
+						  &current_value, ACPI_READ);
+				if (ACPI_FAILURE (status)) {
+					return_ACPI_STATUS (status);
+				}
+
+				merged_value |= (current_value & ~mask);
+			}
+			break;
+
+		case AML_FIELD_UPDATE_WRITE_AS_ONES:
+
+			/* Set positions outside the field to all ones */
+
+			merged_value |= ~mask;
+			break;
+
+		case AML_FIELD_UPDATE_WRITE_AS_ZEROS:
+
+			/* Set positions outside the field to all zeros */
+
+			merged_value &= mask;
+			break;
+
+		default:
+
+			ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
+				"write_with_update_rule: Unknown update_rule setting: %X\n",
+				(obj_desc->common_field.field_flags & AML_FIELD_UPDATE_RULE_MASK)));
+			return_ACPI_STATUS (AE_AML_OPERAND_VALUE);
+		}
+	}
+
+	ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
+		"Mask %8.8X%8.8X, datum_offset %X, Width %X, Value %8.8X%8.8X, merged_value %8.8X%8.8X\n",
+		ACPI_FORMAT_UINT64 (mask),
+		field_datum_byte_offset,
+		obj_desc->common_field.access_byte_width,
+		ACPI_FORMAT_UINT64 (field_value),
+		ACPI_FORMAT_UINT64 (merged_value)));
+
+	/* Write the merged value */
+
+	status = acpi_ex_field_datum_io (obj_desc, field_datum_byte_offset,
+			  &merged_value, ACPI_WRITE);
+
+	return_ACPI_STATUS (status);
+}
+
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_extract_from_field
+ *
+ * PARAMETERS:  obj_desc            - Field to be read
+ *              Buffer              - Where to store the field data
+ *              buffer_length       - Length of Buffer
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Retrieve the current value of the given field
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ex_extract_from_field (
+	union acpi_operand_object       *obj_desc,
+	void                            *buffer,
+	u32                             buffer_length)
+{
+	acpi_status                     status;
+	acpi_integer                    raw_datum;
+	acpi_integer                    merged_datum;
+	u32                             field_offset = 0;
+	u32                             buffer_offset = 0;
+	u32                             buffer_tail_bits;
+	u32                             datum_count;
+	u32                             field_datum_count;
+	u32                             i;
+
+
+	ACPI_FUNCTION_TRACE ("ex_extract_from_field");
+
+
+	/* Validate target buffer and clear it */
+
+	if (buffer_length < ACPI_ROUND_BITS_UP_TO_BYTES (
+			 obj_desc->common_field.bit_length)) {
+		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
+			"Field size %X (bits) is too large for buffer (%X)\n",
+			obj_desc->common_field.bit_length, buffer_length));
+
+		return_ACPI_STATUS (AE_BUFFER_OVERFLOW);
+	}
+	ACPI_MEMSET (buffer, 0, buffer_length);
+
+	/* Compute the number of datums (access width data items) */
+
+	datum_count = ACPI_ROUND_UP_TO (
+			   obj_desc->common_field.bit_length,
+			   obj_desc->common_field.access_bit_width);
+	field_datum_count = ACPI_ROUND_UP_TO (
+			   obj_desc->common_field.bit_length +
+			   obj_desc->common_field.start_field_bit_offset,
+			   obj_desc->common_field.access_bit_width);
+
+	/* Priming read from the field */
+
+	status = acpi_ex_field_datum_io (obj_desc, field_offset, &raw_datum, ACPI_READ);
+	if (ACPI_FAILURE (status)) {
+		return_ACPI_STATUS (status);
+	}
+	merged_datum = raw_datum >> obj_desc->common_field.start_field_bit_offset;
+
+	/* Read the rest of the field */
+
+	for (i = 1; i < field_datum_count; i++) {
+		/* Get next input datum from the field */
+
+		field_offset += obj_desc->common_field.access_byte_width;
+		status = acpi_ex_field_datum_io (obj_desc, field_offset,
+				  &raw_datum, ACPI_READ);
+		if (ACPI_FAILURE (status)) {
+			return_ACPI_STATUS (status);
+		}
+
+		/* Merge with previous datum if necessary */
+
+		merged_datum |= raw_datum <<
+			(obj_desc->common_field.access_bit_width - obj_desc->common_field.start_field_bit_offset);
+
+		if (i == datum_count) {
+			break;
+		}
+
+		/* Write merged datum to target buffer */
+
+		ACPI_MEMCPY (((char *) buffer) + buffer_offset, &merged_datum,
+			ACPI_MIN(obj_desc->common_field.access_byte_width,
+					 buffer_length - buffer_offset));
+
+		buffer_offset += obj_desc->common_field.access_byte_width;
+		merged_datum = raw_datum >> obj_desc->common_field.start_field_bit_offset;
+	}
+
+	/* Mask off any extra bits in the last datum */
+
+	buffer_tail_bits = obj_desc->common_field.bit_length % obj_desc->common_field.access_bit_width;
+	if (buffer_tail_bits) {
+		merged_datum &= ACPI_MASK_BITS_ABOVE (buffer_tail_bits);
+	}
+
+	/* Write the last datum to the buffer */
+
+	ACPI_MEMCPY (((char *) buffer) + buffer_offset, &merged_datum,
+		ACPI_MIN(obj_desc->common_field.access_byte_width,
+				 buffer_length - buffer_offset));
+
+	return_ACPI_STATUS (AE_OK);
+}
+
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_insert_into_field
+ *
+ * PARAMETERS:  obj_desc            - Field to be written
+ *              Buffer              - Data to be written
+ *              buffer_length       - Length of Buffer
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Store the Buffer contents into the given field
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ex_insert_into_field (
+	union acpi_operand_object       *obj_desc,
+	void                            *buffer,
+	u32                             buffer_length)
+{
+	acpi_status                     status;
+	acpi_integer                    mask;
+	acpi_integer                    merged_datum;
+	acpi_integer                    raw_datum = 0;
+	u32                             field_offset = 0;
+	u32                             buffer_offset = 0;
+	u32                             buffer_tail_bits;
+	u32                             datum_count;
+	u32                             field_datum_count;
+	u32                             i;
+
+
+	ACPI_FUNCTION_TRACE ("ex_insert_into_field");
+
+
+	/* Validate input buffer */
+
+	if (buffer_length < ACPI_ROUND_BITS_UP_TO_BYTES (
+			 obj_desc->common_field.bit_length)) {
+		ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
+			"Field size %X (bits) is too large for buffer (%X)\n",
+			obj_desc->common_field.bit_length, buffer_length));
+
+		return_ACPI_STATUS (AE_BUFFER_OVERFLOW);
+	}
+
+	/* Compute the number of datums (access width data items) */
+
+	mask = ACPI_MASK_BITS_BELOW (obj_desc->common_field.start_field_bit_offset);
+	datum_count = ACPI_ROUND_UP_TO (obj_desc->common_field.bit_length,
+			  obj_desc->common_field.access_bit_width);
+	field_datum_count = ACPI_ROUND_UP_TO (obj_desc->common_field.bit_length +
+			   obj_desc->common_field.start_field_bit_offset,
+			   obj_desc->common_field.access_bit_width);
+
+	/* Get initial Datum from the input buffer */
+
+	ACPI_MEMCPY (&raw_datum, buffer,
+		ACPI_MIN(obj_desc->common_field.access_byte_width,
+				 buffer_length - buffer_offset));
+
+	merged_datum = raw_datum << obj_desc->common_field.start_field_bit_offset;
+
+	/* Write the entire field */
+
+	for (i = 1; i < field_datum_count; i++) {
+		/* Write merged datum to the target field */
+
+		merged_datum &= mask;
+		status = acpi_ex_write_with_update_rule (obj_desc, mask, merged_datum, field_offset);
+		if (ACPI_FAILURE (status)) {
+			return_ACPI_STATUS (status);
+		}
+
+		/* Start new output datum by merging with previous input datum */
+
+		field_offset += obj_desc->common_field.access_byte_width;
+		merged_datum = raw_datum >>
+			(obj_desc->common_field.access_bit_width - obj_desc->common_field.start_field_bit_offset);
+		mask = ACPI_INTEGER_MAX;
+
+		if (i == datum_count) {
+			break;
+		}
+
+		/* Get the next input datum from the buffer */
+
+		buffer_offset += obj_desc->common_field.access_byte_width;
+		ACPI_MEMCPY (&raw_datum, ((char *) buffer) + buffer_offset,
+			ACPI_MIN(obj_desc->common_field.access_byte_width,
+					 buffer_length - buffer_offset));
+		merged_datum |= raw_datum << obj_desc->common_field.start_field_bit_offset;
+	}
+
+	/* Mask off any extra bits in the last datum */
+
+	buffer_tail_bits = (obj_desc->common_field.bit_length +
+			obj_desc->common_field.start_field_bit_offset) % obj_desc->common_field.access_bit_width;
+	if (buffer_tail_bits) {
+		mask &= ACPI_MASK_BITS_ABOVE (buffer_tail_bits);
+	}
+
+	/* Write the last datum to the field */
+
+	merged_datum &= mask;
+	status = acpi_ex_write_with_update_rule (obj_desc, mask, merged_datum, field_offset);
+
+	return_ACPI_STATUS (status);
+}
+
+