LXR linux/drivers/acpi/acpica/exserial.c

   1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2/******************************************************************************
   3 *
   4 * Module Name: exserial - field_unit support for serial address spaces
   5 *
   6 * Copyright (C) 2000 - 2020, Intel Corp.
   7 *
   8 *****************************************************************************/
   9
  10#include <acpi/acpi.h>
  11#include "accommon.h"
  12#include "acdispat.h"
  13#include "acinterp.h"
  14#include "amlcode.h"
  15
  16#define _COMPONENT          ACPI_EXECUTER
  17ACPI_MODULE_NAME("exserial")
  18
  19/*******************************************************************************
  20 *
  21 * FUNCTION:    acpi_ex_read_gpio
  22 *
  23 * PARAMETERS:  obj_desc            - The named field to read
  24 *              buffer              - Where the return data is returned
  25 *
  26 * RETURN:      Status
  27 *
  28 * DESCRIPTION: Read from a named field that references a Generic Serial Bus
  29 *              field
  30 *
  31 ******************************************************************************/
  32acpi_status acpi_ex_read_gpio(union acpi_operand_object *obj_desc, void *buffer)
  33{
  34        acpi_status status;
  35
  36        ACPI_FUNCTION_TRACE_PTR(ex_read_gpio, obj_desc);
  37
  38        /*
  39         * For GPIO (general_purpose_io), the Address will be the bit offset
  40         * from the previous Connection() operator, making it effectively a
  41         * pin number index. The bit_length is the length of the field, which
  42         * is thus the number of pins.
  43         */
  44        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
  45                          "GPIO FieldRead [FROM]:  Pin %u Bits %u\n",
  46                          obj_desc->field.pin_number_index,
  47                          obj_desc->field.bit_length));
  48
  49        /* Lock entire transaction if requested */
  50
  51        acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
  52
  53        /* Perform the read */
  54
  55        status = acpi_ex_access_region(obj_desc, 0, (u64 *)buffer, ACPI_READ);
  56
  57        acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
  58        return_ACPI_STATUS(status);
  59}
  60
  61/*******************************************************************************
  62 *
  63 * FUNCTION:    acpi_ex_write_gpio
  64 *
  65 * PARAMETERS:  source_desc         - Contains data to write. Expect to be
  66 *                                    an Integer object.
  67 *              obj_desc            - The named field
  68 *              result_desc         - Where the return value is returned, if any
  69 *
  70 * RETURN:      Status
  71 *
  72 * DESCRIPTION: Write to a named field that references a General Purpose I/O
  73 *              field.
  74 *
  75 ******************************************************************************/
  76
  77acpi_status
  78acpi_ex_write_gpio(union acpi_operand_object *source_desc,
  79                   union acpi_operand_object *obj_desc,
  80                   union acpi_operand_object **return_buffer)
  81{
  82        acpi_status status;
  83        void *buffer;
  84
  85        ACPI_FUNCTION_TRACE_PTR(ex_write_gpio, obj_desc);
  86
  87        /*
  88         * For GPIO (general_purpose_io), we will bypass the entire field
  89         * mechanism and handoff the bit address and bit width directly to
  90         * the handler. The Address will be the bit offset
  91         * from the previous Connection() operator, making it effectively a
  92         * pin number index. The bit_length is the length of the field, which
  93         * is thus the number of pins.
  94         */
  95        if (source_desc->common.type != ACPI_TYPE_INTEGER) {
  96                return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
  97        }
  98
  99        ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 100                          "GPIO FieldWrite [FROM]: (%s:%X), Value %.8X  [TO]: Pin %u Bits %u\n",
 101                          acpi_ut_get_type_name(source_desc->common.type),
 102                          source_desc->common.type,
 103                          (u32)source_desc->integer.value,
 104                          obj_desc->field.pin_number_index,
 105                          obj_desc->field.bit_length));
 106
 107        buffer = &source_desc->integer.value;
 108
 109        /* Lock entire transaction if requested */
 110
 111        acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 112
 113        /* Perform the write */
 114
 115        status = acpi_ex_access_region(obj_desc, 0, (u64 *)buffer, ACPI_WRITE);
 116        acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 117        return_ACPI_STATUS(status);
 118}
 119
 120/*******************************************************************************
 121 *
 122 * FUNCTION:    acpi_ex_read_serial_bus
 123 *
 124 * PARAMETERS:  obj_desc            - The named field to read
 125 *              return_buffer       - Where the return value is returned, if any
 126 *
 127 * RETURN:      Status
 128 *
 129 * DESCRIPTION: Read from a named field that references a serial bus
 130 *              (SMBus, IPMI, or GSBus).
 131 *
 132 ******************************************************************************/
 133
 134acpi_status
 135acpi_ex_read_serial_bus(union acpi_operand_object *obj_desc,
 136                        union acpi_operand_object **return_buffer)
 137{
 138        acpi_status status;
 139        u32 buffer_length;
 140        union acpi_operand_object *buffer_desc;
 141        u32 function;
 142        u16 accessor_type;
 143
 144        ACPI_FUNCTION_TRACE_PTR(ex_read_serial_bus, obj_desc);
 145
 146        /*
 147         * This is an SMBus, GSBus or IPMI read. We must create a buffer to
 148         * hold the data and then directly access the region handler.
 149         *
 150         * Note: SMBus and GSBus protocol value is passed in upper 16-bits
 151         * of Function
 152         *
 153         * Common buffer format:
 154         *     Status;    (Byte 0 of the data buffer)
 155         *     Length;    (Byte 1 of the data buffer)
 156         *     Data[x-1]: (Bytes 2-x of the arbitrary length data buffer)
 157         */
 158        switch (obj_desc->field.region_obj->region.space_id) {
 159        case ACPI_ADR_SPACE_SMBUS:
 160
 161                buffer_length = ACPI_SMBUS_BUFFER_SIZE;
 162                function = ACPI_READ | (obj_desc->field.attribute << 16);
 163                break;
 164
 165        case ACPI_ADR_SPACE_IPMI:
 166
 167                buffer_length = ACPI_IPMI_BUFFER_SIZE;
 168                function = ACPI_READ;
 169                break;
 170
 171        case ACPI_ADR_SPACE_GSBUS:
 172
 173                accessor_type = obj_desc->field.attribute;
 174                if (accessor_type == AML_FIELD_ATTRIB_RAW_PROCESS_BYTES) {
 175                        ACPI_ERROR((AE_INFO,
 176                                    "Invalid direct read using bidirectional write-then-read protocol"));
 177
 178                        return_ACPI_STATUS(AE_AML_PROTOCOL);
 179                }
 180
 181                status =
 182                    acpi_ex_get_protocol_buffer_length(accessor_type,
 183                                                       &buffer_length);
 184                if (ACPI_FAILURE(status)) {
 185                        ACPI_ERROR((AE_INFO,
 186                                    "Invalid protocol ID for GSBus: 0x%4.4X",
 187                                    accessor_type));
 188
 189                        return_ACPI_STATUS(status);
 190                }
 191
 192                /* Add header length to get the full size of the buffer */
 193
 194                buffer_length += ACPI_SERIAL_HEADER_SIZE;
 195                function = ACPI_READ | (accessor_type << 16);
 196                break;
 197
 198        default:
 199                return_ACPI_STATUS(AE_AML_INVALID_SPACE_ID);
 200        }
 201
 202        /* Create the local transfer buffer that is returned to the caller */
 203
 204        buffer_desc = acpi_ut_create_buffer_object(buffer_length);
 205        if (!buffer_desc) {
 206                return_ACPI_STATUS(AE_NO_MEMORY);
 207        }
 208
 209        /* Lock entire transaction if requested */
 210
 211        acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 212
 213        /* Call the region handler for the write-then-read */
 214
 215        status = acpi_ex_access_region(obj_desc, 0,
 216                                       ACPI_CAST_PTR(u64,
 217                                                     buffer_desc->buffer.
 218                                                     pointer), function);
 219        acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 220
 221        *return_buffer = buffer_desc;
 222        return_ACPI_STATUS(status);
 223}
 224
 225/*******************************************************************************
 226 *
 227 * FUNCTION:    acpi_ex_write_serial_bus
 228 *
 229 * PARAMETERS:  source_desc         - Contains data to write
 230 *              obj_desc            - The named field
 231 *              return_buffer       - Where the return value is returned, if any
 232 *
 233 * RETURN:      Status
 234 *
 235 * DESCRIPTION: Write to a named field that references a serial bus
 236 *              (SMBus, IPMI, GSBus).
 237 *
 238 ******************************************************************************/
 239
 240acpi_status
 241acpi_ex_write_serial_bus(union acpi_operand_object *source_desc,
 242                         union acpi_operand_object *obj_desc,
 243                         union acpi_operand_object **return_buffer)
 244{
 245        acpi_status status;
 246        u32 buffer_length;
 247        u32 data_length;
 248        void *buffer;
 249        union acpi_operand_object *buffer_desc;
 250        u32 function;
 251        u16 accessor_type;
 252
 253        ACPI_FUNCTION_TRACE_PTR(ex_write_serial_bus, obj_desc);
 254
 255        /*
 256         * This is an SMBus, GSBus or IPMI write. We will bypass the entire
 257         * field mechanism and handoff the buffer directly to the handler.
 258         * For these address spaces, the buffer is bidirectional; on a
 259         * write, return data is returned in the same buffer.
 260         *
 261         * Source must be a buffer of sufficient size, these are fixed size:
 262         * ACPI_SMBUS_BUFFER_SIZE, or ACPI_IPMI_BUFFER_SIZE.
 263         *
 264         * Note: SMBus and GSBus protocol type is passed in upper 16-bits
 265         * of Function
 266         *
 267         * Common buffer format:
 268         *     Status;    (Byte 0 of the data buffer)
 269         *     Length;    (Byte 1 of the data buffer)
 270         *     Data[x-1]: (Bytes 2-x of the arbitrary length data buffer)
 271         */
 272        if (source_desc->common.type != ACPI_TYPE_BUFFER) {
 273                ACPI_ERROR((AE_INFO,
 274                            "SMBus/IPMI/GenericSerialBus write requires "
 275                            "Buffer, found type %s",
 276                            acpi_ut_get_object_type_name(source_desc)));
 277
 278                return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 279        }
 280
 281        switch (obj_desc->field.region_obj->region.space_id) {
 282        case ACPI_ADR_SPACE_SMBUS:
 283
 284                buffer_length = ACPI_SMBUS_BUFFER_SIZE;
 285                function = ACPI_WRITE | (obj_desc->field.attribute << 16);
 286                break;
 287
 288        case ACPI_ADR_SPACE_IPMI:
 289
 290                buffer_length = ACPI_IPMI_BUFFER_SIZE;
 291                function = ACPI_WRITE;
 292                break;
 293
 294        case ACPI_ADR_SPACE_GSBUS:
 295
 296                accessor_type = obj_desc->field.attribute;
 297                status =
 298                    acpi_ex_get_protocol_buffer_length(accessor_type,
 299                                                       &buffer_length);
 300                if (ACPI_FAILURE(status)) {
 301                        ACPI_ERROR((AE_INFO,
 302                                    "Invalid protocol ID for GSBus: 0x%4.4X",
 303                                    accessor_type));
 304
 305                        return_ACPI_STATUS(status);
 306                }
 307
 308                /* Add header length to get the full size of the buffer */
 309
 310                buffer_length += ACPI_SERIAL_HEADER_SIZE;
 311                function = ACPI_WRITE | (accessor_type << 16);
 312                break;
 313
 314        default:
 315                return_ACPI_STATUS(AE_AML_INVALID_SPACE_ID);
 316        }
 317
 318        /* Create the transfer/bidirectional/return buffer */
 319
 320        buffer_desc = acpi_ut_create_buffer_object(buffer_length);
 321        if (!buffer_desc) {
 322                return_ACPI_STATUS(AE_NO_MEMORY);
 323        }
 324
 325        /* Copy the input buffer data to the transfer buffer */
 326
 327        buffer = buffer_desc->buffer.pointer;
 328        data_length = (buffer_length < source_desc->buffer.length ?
 329                       buffer_length : source_desc->buffer.length);
 330        memcpy(buffer, source_desc->buffer.pointer, data_length);
 331
 332        /* Lock entire transaction if requested */
 333
 334        acpi_ex_acquire_global_lock(obj_desc->common_field.field_flags);
 335
 336        /*
 337         * Perform the write (returns status and perhaps data in the
 338         * same buffer)
 339         */
 340        status = acpi_ex_access_region(obj_desc, 0, (u64 *)buffer, function);
 341        acpi_ex_release_global_lock(obj_desc->common_field.field_flags);
 342
 343        *return_buffer = buffer_desc;
 344        return_ACPI_STATUS(status);
 345}
 346