drivers/acpi/acpica/exserial.c - linux - Git at Google

 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
 /******************************************************************************
  *
  * Module Name: exserial - field_unit support for serial address spaces
  *
  * Copyright (C) 2000 - 2023, Intel Corp.
  *
  *****************************************************************************/

 #include <acpi/acpi.h>
 #include "accommon.h"
 #include "acdispat.h"
 #include "acinterp.h"
 #include "amlcode.h"

 #define _COMPONENT          ACPI_EXECUTER
 ACPI_MODULE_NAME("exserial")

 /*******************************************************************************
  *
  * FUNCTION:    acpi_ex_read_gpio
  *
  * PARAMETERS:  obj_desc            - The named field to read
  *              buffer              - Where the return data is returned
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Read from a named field that references a Generic Serial Bus
  *              field
  *
  ******************************************************************************/
 acpi_status acpi_ex_read_gpio(union acpi_operand_object *obj_desc, void *buffer)
 {
 	acpi_status status;

 	ACPI_FUNCTION_TRACE_PTR(ex_read_gpio, obj_desc);

 	/*
 	 * For GPIO (general_purpose_io), the Address will be the bit offset
 	 * from the previous Connection() operator, making it effectively a
 	 * pin number index. The bit_length is the length of the field, which
 	 * is thus the number of pins.
 	 */
 	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 			  "GPIO FieldRead [FROM]:  Pin %u Bits %u\n",
 			  obj_desc->field.pin_number_index,
 			  obj_desc->field.bit_length));

 	/* Lock entire transaction if requested */

 	acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);

 	/* Perform the read */

 	status = acpi_ex_access_region(obj_desc, 0, (u64 *)buffer, ACPI_READ);

 	acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 	return_ACPI_STATUS(status);
 }

 /*******************************************************************************
  *
  * FUNCTION:    acpi_ex_write_gpio
  *
  * PARAMETERS:  source_desc         - Contains data to write. Expect to be
  *                                    an Integer object.
  *              obj_desc            - The named field
  *              result_desc         - Where the return value is returned, if any
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Write to a named field that references a General Purpose I/O
  *              field.
  *
  ******************************************************************************/

 acpi_status
 acpi_ex_write_gpio(union acpi_operand_object *source_desc,
 		   union acpi_operand_object *obj_desc,
 		   union acpi_operand_object **return_buffer)
 {
 	acpi_status status;
 	void *buffer;

 	ACPI_FUNCTION_TRACE_PTR(ex_write_gpio, obj_desc);

 	/*
 	 * For GPIO (general_purpose_io), we will bypass the entire field
 	 * mechanism and handoff the bit address and bit width directly to
 	 * the handler. The Address will be the bit offset
 	 * from the previous Connection() operator, making it effectively a
 	 * pin number index. The bit_length is the length of the field, which
 	 * is thus the number of pins.
 	 */
 	if (source_desc->common.type != ACPI_TYPE_INTEGER) {
 		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 	}

 	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 			  "GPIO FieldWrite [FROM]: (%s:%X), Value %.8X  [TO]: Pin %u Bits %u\n",
 			  acpi_ut_get_type_name(source_desc->common.type),
 			  source_desc->common.type,
 			  (u32)source_desc->integer.value,
 			  obj_desc->field.pin_number_index,
 			  obj_desc->field.bit_length));

 	buffer = &source_desc->integer.value;

 	/* Lock entire transaction if requested */

 	acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);

 	/* Perform the write */

 	status = acpi_ex_access_region(obj_desc, 0, (u64 *)buffer, ACPI_WRITE);
 	acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 	return_ACPI_STATUS(status);
 }

 /*******************************************************************************
  *
  * FUNCTION:    acpi_ex_read_serial_bus
  *
  * PARAMETERS:  obj_desc            - The named field to read
  *              return_buffer       - Where the return value is returned, if any
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Read from a named field that references a serial bus
  *              (SMBus, IPMI, or GSBus).
  *
  ******************************************************************************/

 acpi_status
 acpi_ex_read_serial_bus(union acpi_operand_object *obj_desc,
 			union acpi_operand_object **return_buffer)
 {
 	acpi_status status;
 	u32 buffer_length;
 	union acpi_operand_object *buffer_desc;
 	u32 function;
 	u16 accessor_type;

 	ACPI_FUNCTION_TRACE_PTR(ex_read_serial_bus, obj_desc);

 	/*
 	 * This is an SMBus, GSBus or IPMI read. We must create a buffer to
 	 * hold the data and then directly access the region handler.
 	 *
 	 * Note: SMBus and GSBus protocol value is passed in upper 16-bits
 	 * of Function
 	 *
 	 * Common buffer format:
 	 *     Status;    (Byte 0 of the data buffer)
 	 *     Length;    (Byte 1 of the data buffer)
 	 *     Data[x-1]: (Bytes 2-x of the arbitrary length data buffer)
 	 */
 	switch (obj_desc->field.region_obj->region.space_id) {
 	case ACPI_ADR_SPACE_SMBUS:

 		buffer_length = ACPI_SMBUS_BUFFER_SIZE;
 		function = ACPI_READ | (obj_desc->field.attribute << 16);
 		break;

 	case ACPI_ADR_SPACE_IPMI:

 		buffer_length = ACPI_IPMI_BUFFER_SIZE;
 		function = ACPI_READ;
 		break;

 	case ACPI_ADR_SPACE_GSBUS:

 		accessor_type = obj_desc->field.attribute;
 		if (accessor_type == AML_FIELD_ATTRIB_RAW_PROCESS_BYTES) {
 			ACPI_ERROR((AE_INFO,
 				    "Invalid direct read using bidirectional write-then-read protocol"));

 			return_ACPI_STATUS(AE_AML_PROTOCOL);
 		}

 		status =
 		    acpi_ex_get_protocol_buffer_length(accessor_type,
 						       &buffer_length);
 		if (ACPI_FAILURE(status)) {
 			ACPI_ERROR((AE_INFO,
 				    "Invalid protocol ID for GSBus: 0x%4.4X",
 				    accessor_type));

 			return_ACPI_STATUS(status);
 		}

 		/* Add header length to get the full size of the buffer */

 		buffer_length += ACPI_SERIAL_HEADER_SIZE;
 		function = ACPI_READ | (accessor_type << 16);
 		break;

 	case ACPI_ADR_SPACE_PLATFORM_RT:

 		buffer_length = ACPI_PRM_INPUT_BUFFER_SIZE;
 		function = ACPI_READ;
 		break;

 	default:
 		return_ACPI_STATUS(AE_AML_INVALID_SPACE_ID);
 	}

 	/* Create the local transfer buffer that is returned to the caller */

 	buffer_desc = acpi_ut_create_buffer_object(buffer_length);
 	if (!buffer_desc) {
 		return_ACPI_STATUS(AE_NO_MEMORY);
 	}

 	/* Lock entire transaction if requested */

 	acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);

 	/* Call the region handler for the write-then-read */

 	status = acpi_ex_access_region(obj_desc, 0,
 				       ACPI_CAST_PTR(u64,
 						     buffer_desc->buffer.
 						     pointer), function);
 	acpi_ex_release_global_lock(obj_desc->common_field.field_flags);

 	*return_buffer = buffer_desc;
 	return_ACPI_STATUS(status);
 }

 /*******************************************************************************
  *
  * FUNCTION:    acpi_ex_write_serial_bus
  *
  * PARAMETERS:  source_desc         - Contains data to write
  *              obj_desc            - The named field
  *              return_buffer       - Where the return value is returned, if any
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Write to a named field that references a serial bus
  *              (SMBus, IPMI, GSBus).
  *
  ******************************************************************************/

 acpi_status
 acpi_ex_write_serial_bus(union acpi_operand_object *source_desc,
 			 union acpi_operand_object *obj_desc,
 			 union acpi_operand_object **return_buffer)
 {
 	acpi_status status;
 	u32 buffer_length;
 	u32 data_length;
 	void *buffer;
 	union acpi_operand_object *buffer_desc;
 	u32 function;
 	u16 accessor_type;

 	ACPI_FUNCTION_TRACE_PTR(ex_write_serial_bus, obj_desc);

 	/*
 	 * This is an SMBus, GSBus or IPMI write. We will bypass the entire
 	 * field mechanism and handoff the buffer directly to the handler.
 	 * For these address spaces, the buffer is bidirectional; on a
 	 * write, return data is returned in the same buffer.
 	 *
 	 * Source must be a buffer of sufficient size, these are fixed size:
 	 * ACPI_SMBUS_BUFFER_SIZE, or ACPI_IPMI_BUFFER_SIZE.
 	 *
 	 * Note: SMBus and GSBus protocol type is passed in upper 16-bits
 	 * of Function
 	 *
 	 * Common buffer format:
 	 *     Status;    (Byte 0 of the data buffer)
 	 *     Length;    (Byte 1 of the data buffer)
 	 *     Data[x-1]: (Bytes 2-x of the arbitrary length data buffer)
 	 */
 	if (source_desc->common.type != ACPI_TYPE_BUFFER) {
 		ACPI_ERROR((AE_INFO,
 			    "SMBus/IPMI/GenericSerialBus write requires "
 			    "Buffer, found type %s",
 			    acpi_ut_get_object_type_name(source_desc)));

 		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 	}

 	switch (obj_desc->field.region_obj->region.space_id) {
 	case ACPI_ADR_SPACE_SMBUS:

 		buffer_length = ACPI_SMBUS_BUFFER_SIZE;
 		function = ACPI_WRITE | (obj_desc->field.attribute << 16);
 		break;

 	case ACPI_ADR_SPACE_IPMI:

 		buffer_length = ACPI_IPMI_BUFFER_SIZE;
 		function = ACPI_WRITE;
 		break;

 	case ACPI_ADR_SPACE_GSBUS:

 		accessor_type = obj_desc->field.attribute;
 		status =
 		    acpi_ex_get_protocol_buffer_length(accessor_type,
 						       &buffer_length);
 		if (ACPI_FAILURE(status)) {
 			ACPI_ERROR((AE_INFO,
 				    "Invalid protocol ID for GSBus: 0x%4.4X",
 				    accessor_type));

 			return_ACPI_STATUS(status);
 		}

 		/* Add header length to get the full size of the buffer */

 		buffer_length += ACPI_SERIAL_HEADER_SIZE;
 		function = ACPI_WRITE | (accessor_type << 16);
 		break;

 	case ACPI_ADR_SPACE_PLATFORM_RT:

 		buffer_length = ACPI_PRM_INPUT_BUFFER_SIZE;
 		function = ACPI_WRITE;
 		break;

 	case ACPI_ADR_SPACE_FIXED_HARDWARE:

 		buffer_length = ACPI_FFH_INPUT_BUFFER_SIZE;
 		function = ACPI_WRITE;
 		break;

 	default:
 		return_ACPI_STATUS(AE_AML_INVALID_SPACE_ID);
 	}

 	/* Create the transfer/bidirectional/return buffer */

 	buffer_desc = acpi_ut_create_buffer_object(buffer_length);
 	if (!buffer_desc) {
 		return_ACPI_STATUS(AE_NO_MEMORY);
 	}

 	/* Copy the input buffer data to the transfer buffer */

 	buffer = buffer_desc->buffer.pointer;
 	data_length = ACPI_MIN(buffer_length, source_desc->buffer.length);
 	memcpy(buffer, source_desc->buffer.pointer, data_length);

 	/* Lock entire transaction if requested */

 	acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);

 	/*
 	 * Perform the write (returns status and perhaps data in the
 	 * same buffer)
 	 */
 	status = acpi_ex_access_region(obj_desc, 0, (u64 *)buffer, function);
 	acpi_ex_release_global_lock(obj_desc->common_field.field_flags);

 	*return_buffer = buffer_desc;
 	return_ACPI_STATUS(status);
 }
	// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
	/******************************************************************************
	*
	* Module Name: exserial - field_unit support for serial address spaces
	*
	* Copyright (C) 2000 - 2023, Intel Corp.
	*
	*****************************************************************************/

	#include <acpi/acpi.h>
	#include "accommon.h"
	#include "acdispat.h"
	#include "acinterp.h"
	#include "amlcode.h"

	#define _COMPONENT ACPI_EXECUTER
	ACPI_MODULE_NAME("exserial")

	/*******************************************************************************
	*
	* FUNCTION: acpi_ex_read_gpio
	*
	* PARAMETERS: obj_desc - The named field to read
	* buffer - Where the return data is returned
	*
	* RETURN: Status
	*
	* DESCRIPTION: Read from a named field that references a Generic Serial Bus
	* field
	*
	******************************************************************************/
	acpi_status acpi_ex_read_gpio(union acpi_operand_object obj_desc, void buffer)
	{
	acpi_status status;

	ACPI_FUNCTION_TRACE_PTR(ex_read_gpio, obj_desc);

	/*
	* For GPIO (general_purpose_io), the Address will be the bit offset
	* from the previous Connection() operator, making it effectively a
	* pin number index. The bit_length is the length of the field, which
	* is thus the number of pins.
	*/
	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
	"GPIO FieldRead [FROM]: Pin %u Bits %u\n",
	obj_desc->field.pin_number_index,
	obj_desc->field.bit_length));

	/* Lock entire transaction if requested */

	acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);

	/* Perform the read */

	status = acpi_ex_access_region(obj_desc, 0, (u64 *)buffer, ACPI_READ);

	acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
	return_ACPI_STATUS(status);
	}

	/*******************************************************************************
	*
	* FUNCTION: acpi_ex_write_gpio
	*
	* PARAMETERS: source_desc - Contains data to write. Expect to be
	* an Integer object.
	* obj_desc - The named field
	* result_desc - Where the return value is returned, if any
	*
	* RETURN: Status
	*
	* DESCRIPTION: Write to a named field that references a General Purpose I/O
	* field.
	*
	******************************************************************************/

	acpi_status
	acpi_ex_write_gpio(union acpi_operand_object *source_desc,
	union acpi_operand_object *obj_desc,
	union acpi_operand_object **return_buffer)
	{
	acpi_status status;
	void *buffer;

	ACPI_FUNCTION_TRACE_PTR(ex_write_gpio, obj_desc);

	/*
	* For GPIO (general_purpose_io), we will bypass the entire field
	* mechanism and handoff the bit address and bit width directly to
	* the handler. The Address will be the bit offset
	* from the previous Connection() operator, making it effectively a
	* pin number index. The bit_length is the length of the field, which
	* is thus the number of pins.
	*/
	if (source_desc->common.type != ACPI_TYPE_INTEGER) {
	return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
	}

	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
	"GPIO FieldWrite [FROM]: (%s:%X), Value %.8X [TO]: Pin %u Bits %u\n",
	acpi_ut_get_type_name(source_desc->common.type),
	source_desc->common.type,
	(u32)source_desc->integer.value,
	obj_desc->field.pin_number_index,
	obj_desc->field.bit_length));

	buffer = &source_desc->integer.value;

	/* Lock entire transaction if requested */

	acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);

	/* Perform the write */

	status = acpi_ex_access_region(obj_desc, 0, (u64 *)buffer, ACPI_WRITE);
	acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
	return_ACPI_STATUS(status);
	}

	/*******************************************************************************
	*
	* FUNCTION: acpi_ex_read_serial_bus
	*
	* PARAMETERS: obj_desc - The named field to read
	* return_buffer - Where the return value is returned, if any
	*
	* RETURN: Status
	*
	* DESCRIPTION: Read from a named field that references a serial bus
	* (SMBus, IPMI, or GSBus).
	*
	******************************************************************************/

	acpi_status
	acpi_ex_read_serial_bus(union acpi_operand_object *obj_desc,
	union acpi_operand_object **return_buffer)
	{
	acpi_status status;
	u32 buffer_length;
	union acpi_operand_object *buffer_desc;
	u32 function;
	u16 accessor_type;

	ACPI_FUNCTION_TRACE_PTR(ex_read_serial_bus, obj_desc);

	/*
	* This is an SMBus, GSBus or IPMI read. We must create a buffer to
	* hold the data and then directly access the region handler.
	*
	* Note: SMBus and GSBus protocol value is passed in upper 16-bits
	* of Function
	*
	* Common buffer format:
	* Status; (Byte 0 of the data buffer)
	* Length; (Byte 1 of the data buffer)
	* Data[x-1]: (Bytes 2-x of the arbitrary length data buffer)
	*/
	switch (obj_desc->field.region_obj->region.space_id) {
	case ACPI_ADR_SPACE_SMBUS:

	buffer_length = ACPI_SMBUS_BUFFER_SIZE;
	function = ACPI_READ \| (obj_desc->field.attribute << 16);
	break;

	case ACPI_ADR_SPACE_IPMI:

	buffer_length = ACPI_IPMI_BUFFER_SIZE;
	function = ACPI_READ;
	break;

	case ACPI_ADR_SPACE_GSBUS:

	accessor_type = obj_desc->field.attribute;
	if (accessor_type == AML_FIELD_ATTRIB_RAW_PROCESS_BYTES) {
	ACPI_ERROR((AE_INFO,
	"Invalid direct read using bidirectional write-then-read protocol"));

	return_ACPI_STATUS(AE_AML_PROTOCOL);
	}

	status =
	acpi_ex_get_protocol_buffer_length(accessor_type,
	&buffer_length);
	if (ACPI_FAILURE(status)) {
	ACPI_ERROR((AE_INFO,
	"Invalid protocol ID for GSBus: 0x%4.4X",
	accessor_type));

	return_ACPI_STATUS(status);
	}

	/* Add header length to get the full size of the buffer */

	buffer_length += ACPI_SERIAL_HEADER_SIZE;
	function = ACPI_READ \| (accessor_type << 16);
	break;

	case ACPI_ADR_SPACE_PLATFORM_RT:

	buffer_length = ACPI_PRM_INPUT_BUFFER_SIZE;
	function = ACPI_READ;
	break;

	default:
	return_ACPI_STATUS(AE_AML_INVALID_SPACE_ID);
	}

	/* Create the local transfer buffer that is returned to the caller */

	buffer_desc = acpi_ut_create_buffer_object(buffer_length);
	if (!buffer_desc) {
	return_ACPI_STATUS(AE_NO_MEMORY);
	}

	/* Lock entire transaction if requested */

	acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);

	/* Call the region handler for the write-then-read */

	status = acpi_ex_access_region(obj_desc, 0,
	ACPI_CAST_PTR(u64,
	buffer_desc->buffer.
	pointer), function);
	acpi_ex_release_global_lock(obj_desc->common_field.field_flags);

	*return_buffer = buffer_desc;
	return_ACPI_STATUS(status);
	}

	/*******************************************************************************
	*
	* FUNCTION: acpi_ex_write_serial_bus
	*
	* PARAMETERS: source_desc - Contains data to write
	* obj_desc - The named field
	* return_buffer - Where the return value is returned, if any
	*
	* RETURN: Status
	*
	* DESCRIPTION: Write to a named field that references a serial bus
	* (SMBus, IPMI, GSBus).
	*
	******************************************************************************/

	acpi_status
	acpi_ex_write_serial_bus(union acpi_operand_object *source_desc,
	union acpi_operand_object *obj_desc,
	union acpi_operand_object **return_buffer)
	{
	acpi_status status;
	u32 buffer_length;
	u32 data_length;
	void *buffer;
	union acpi_operand_object *buffer_desc;
	u32 function;
	u16 accessor_type;

	ACPI_FUNCTION_TRACE_PTR(ex_write_serial_bus, obj_desc);

	/*
	* This is an SMBus, GSBus or IPMI write. We will bypass the entire
	* field mechanism and handoff the buffer directly to the handler.
	* For these address spaces, the buffer is bidirectional; on a
	* write, return data is returned in the same buffer.
	*
	* Source must be a buffer of sufficient size, these are fixed size:
	* ACPI_SMBUS_BUFFER_SIZE, or ACPI_IPMI_BUFFER_SIZE.
	*
	* Note: SMBus and GSBus protocol type is passed in upper 16-bits
	* of Function
	*
	* Common buffer format:
	* Status; (Byte 0 of the data buffer)
	* Length; (Byte 1 of the data buffer)
	* Data[x-1]: (Bytes 2-x of the arbitrary length data buffer)
	*/
	if (source_desc->common.type != ACPI_TYPE_BUFFER) {
	ACPI_ERROR((AE_INFO,
	"SMBus/IPMI/GenericSerialBus write requires "
	"Buffer, found type %s",
	acpi_ut_get_object_type_name(source_desc)));

	return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
	}

	switch (obj_desc->field.region_obj->region.space_id) {
	case ACPI_ADR_SPACE_SMBUS:

	buffer_length = ACPI_SMBUS_BUFFER_SIZE;
	function = ACPI_WRITE \| (obj_desc->field.attribute << 16);
	break;

	case ACPI_ADR_SPACE_IPMI:

	buffer_length = ACPI_IPMI_BUFFER_SIZE;
	function = ACPI_WRITE;
	break;

	case ACPI_ADR_SPACE_GSBUS:

	accessor_type = obj_desc->field.attribute;
	status =
	acpi_ex_get_protocol_buffer_length(accessor_type,
	&buffer_length);
	if (ACPI_FAILURE(status)) {
	ACPI_ERROR((AE_INFO,
	"Invalid protocol ID for GSBus: 0x%4.4X",
	accessor_type));

	return_ACPI_STATUS(status);
	}

	/* Add header length to get the full size of the buffer */

	buffer_length += ACPI_SERIAL_HEADER_SIZE;
	function = ACPI_WRITE \| (accessor_type << 16);
	break;

	case ACPI_ADR_SPACE_PLATFORM_RT:

	buffer_length = ACPI_PRM_INPUT_BUFFER_SIZE;
	function = ACPI_WRITE;
	break;

	case ACPI_ADR_SPACE_FIXED_HARDWARE:

	buffer_length = ACPI_FFH_INPUT_BUFFER_SIZE;
	function = ACPI_WRITE;
	break;

	default:
	return_ACPI_STATUS(AE_AML_INVALID_SPACE_ID);
	}

	/* Create the transfer/bidirectional/return buffer */

	buffer_desc = acpi_ut_create_buffer_object(buffer_length);
	if (!buffer_desc) {
	return_ACPI_STATUS(AE_NO_MEMORY);
	}

	/* Copy the input buffer data to the transfer buffer */

	buffer = buffer_desc->buffer.pointer;
	data_length = ACPI_MIN(buffer_length, source_desc->buffer.length);
	memcpy(buffer, source_desc->buffer.pointer, data_length);

	/* Lock entire transaction if requested */

	acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);

	/*
	* Perform the write (returns status and perhaps data in the
	* same buffer)
	*/
	status = acpi_ex_access_region(obj_desc, 0, (u64 *)buffer, function);
	acpi_ex_release_global_lock(obj_desc->common_field.field_flags);

	*return_buffer = buffer_desc;
	return_ACPI_STATUS(status);
	}