From f99b89eefeb635a675b2883fcd2148b7cfc77319 Mon Sep 17 00:00:00 2001 From: Bob Moore Date: Wed, 3 Oct 2018 11:45:34 -0700 Subject: ACPICA: Update for generic_serial_bus and attrib_raw_process_bytes protocol Cleanup for this write-then-read protocol. The ACPI specification is rather unclear for the entire generic_serial_bus, but this change works correctly on the Surface 3. Reported-by: Hans de Goede Signed-off-by: Bob Moore Signed-off-by: Erik Schmauss Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpica/exfield.c | 44 ++++++++++++++++++++++++++++++++++--------- 1 file changed, 35 insertions(+), 9 deletions(-) (limited to 'drivers/acpi/acpica/exfield.c') diff --git a/drivers/acpi/acpica/exfield.c b/drivers/acpi/acpica/exfield.c index b272c329d45d..17b937c5144f 100644 --- a/drivers/acpi/acpica/exfield.c +++ b/drivers/acpi/acpica/exfield.c @@ -60,11 +60,19 @@ acpi_ex_get_serial_access_length(u32 accessor_type, u32 access_length) case AML_FIELD_ATTRIB_MULTIBYTE: case AML_FIELD_ATTRIB_RAW_BYTES: - case AML_FIELD_ATTRIB_RAW_PROCESS: length = access_length; break; + case AML_FIELD_ATTRIB_RAW_PROCESS: + /* + * Worst case bidirectional buffer size. This ignores the + * access_length argument to access_as because it is not needed. + * August 2018. + */ + length = ACPI_MAX_GSBUS_BUFFER_SIZE; + break; + case AML_FIELD_ATTRIB_BLOCK: case AML_FIELD_ATTRIB_BLOCK_CALL: default: @@ -147,6 +155,13 @@ acpi_ex_read_data_from_field(struct acpi_walk_state *walk_state, } else if (obj_desc->field.region_obj->region.space_id == ACPI_ADR_SPACE_GSBUS) { accessor_type = obj_desc->field.attribute; + if (accessor_type == AML_FIELD_ATTRIB_RAW_PROCESS) { + ACPI_ERROR((AE_INFO, + "Invalid direct read using bidirectional write-then-read protocol")); + + return_ACPI_STATUS(AE_AML_PROTOCOL); + } + length = acpi_ex_get_serial_access_length(accessor_type, obj_desc->field. @@ -305,6 +320,7 @@ acpi_ex_write_data_to_field(union acpi_operand_object *source_desc, { acpi_status status; u32 length; + u32 data_length; void *buffer; union acpi_operand_object *buffer_desc; u32 function; @@ -361,6 +377,7 @@ acpi_ex_write_data_to_field(union acpi_operand_object *source_desc, if (obj_desc->field.region_obj->region.space_id == ACPI_ADR_SPACE_SMBUS) { length = ACPI_SMBUS_BUFFER_SIZE; + data_length = length; function = ACPI_WRITE | (obj_desc->field.attribute << 16); } else if (obj_desc->field.region_obj->region.space_id == @@ -372,38 +389,47 @@ acpi_ex_write_data_to_field(union acpi_operand_object *source_desc, access_length); /* - * Add additional 2 bytes for the generic_serial_bus data buffer: - * + * Buffer format for Generic Serial Bus protocols: * 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) */ - length += 2; + data_length = source_desc->buffer.pointer[1]; /* Data length is 2nd byte */ + if (!data_length) { + ACPI_ERROR((AE_INFO, + "Invalid zero data length in transfer buffer")); + + return_ACPI_STATUS(AE_AML_BUFFER_LENGTH); + } + function = ACPI_WRITE | (accessor_type << 16); } else { /* IPMI */ length = ACPI_IPMI_BUFFER_SIZE; + data_length = length; function = ACPI_WRITE; } - if (source_desc->buffer.length < length) { + if (source_desc->buffer.length < data_length) { ACPI_ERROR((AE_INFO, "SMBus/IPMI/GenericSerialBus write requires " - "Buffer of length %u, found length %u", - length, source_desc->buffer.length)); + "Buffer data length %u, found buffer length %u", + data_length, source_desc->buffer.length)); return_ACPI_STATUS(AE_AML_BUFFER_LIMIT); } - /* Create the bi-directional buffer */ + /* Create the transfer/bidirectional buffer */ buffer_desc = acpi_ut_create_buffer_object(length); if (!buffer_desc) { return_ACPI_STATUS(AE_NO_MEMORY); } + /* Copy the input buffer data to the transfer buffer */ + buffer = buffer_desc->buffer.pointer; - memcpy(buffer, source_desc->buffer.pointer, length); + memcpy(buffer, source_desc->buffer.pointer, data_length); /* Lock entire transaction if requested */ -- cgit v1.2.3