linux/drivers/acpi/x86/apple.c

142 lines
4.3 KiB
C

/*
* apple.c - Apple ACPI quirks
* Copyright (C) 2017 Lukas Wunner <lukas@wunner.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License (version 2) as
* published by the Free Software Foundation.
*/
#include <linux/acpi.h>
#include <linux/bitmap.h>
#include <linux/platform_data/x86/apple.h>
#include <linux/uuid.h>
/* Apple _DSM device properties GUID */
static const guid_t apple_prp_guid =
GUID_INIT(0xa0b5b7c6, 0x1318, 0x441c,
0xb0, 0xc9, 0xfe, 0x69, 0x5e, 0xaf, 0x94, 0x9b);
/**
* acpi_extract_apple_properties - retrieve and convert Apple _DSM properties
* @adev: ACPI device for which to retrieve the properties
*
* Invoke Apple's custom _DSM once to check the protocol version and once more
* to retrieve the properties. They are marshalled up in a single package as
* alternating key/value elements, unlike _DSD which stores them as a package
* of 2-element packages. Convert to _DSD format and make them available under
* the primary fwnode.
*/
void acpi_extract_apple_properties(struct acpi_device *adev)
{
unsigned int i, j = 0, newsize = 0, numprops, numvalid;
union acpi_object *props, *newprops;
unsigned long *valid = NULL;
void *free_space;
if (!x86_apple_machine)
return;
props = acpi_evaluate_dsm_typed(adev->handle, &apple_prp_guid, 1, 0,
NULL, ACPI_TYPE_BUFFER);
if (!props)
return;
if (!props->buffer.length)
goto out_free;
if (props->buffer.pointer[0] != 3) {
acpi_handle_info(adev->handle, FW_INFO
"unsupported properties version %*ph\n",
props->buffer.length, props->buffer.pointer);
goto out_free;
}
ACPI_FREE(props);
props = acpi_evaluate_dsm_typed(adev->handle, &apple_prp_guid, 1, 1,
NULL, ACPI_TYPE_PACKAGE);
if (!props)
return;
numprops = props->package.count / 2;
if (!numprops)
goto out_free;
valid = bitmap_zalloc(numprops, GFP_KERNEL);
if (!valid)
goto out_free;
/* newsize = key length + value length of each tuple */
for (i = 0; i < numprops; i++) {
union acpi_object *key = &props->package.elements[i * 2];
union acpi_object *val = &props->package.elements[i * 2 + 1];
if ( key->type != ACPI_TYPE_STRING ||
(val->type != ACPI_TYPE_INTEGER &&
val->type != ACPI_TYPE_BUFFER))
continue; /* skip invalid properties */
__set_bit(i, valid);
newsize += key->string.length + 1;
if ( val->type == ACPI_TYPE_BUFFER)
newsize += val->buffer.length;
}
numvalid = bitmap_weight(valid, numprops);
if (numprops > numvalid)
acpi_handle_info(adev->handle, FW_INFO
"skipped %u properties: wrong type\n",
numprops - numvalid);
if (numvalid == 0)
goto out_free;
/* newsize += top-level package + 3 objects for each key/value tuple */
newsize += (1 + 3 * numvalid) * sizeof(union acpi_object);
newprops = ACPI_ALLOCATE_ZEROED(newsize);
if (!newprops)
goto out_free;
/* layout: top-level package | packages | key/value tuples | strings */
newprops->type = ACPI_TYPE_PACKAGE;
newprops->package.count = numvalid;
newprops->package.elements = &newprops[1];
free_space = &newprops[1 + 3 * numvalid];
for_each_set_bit(i, valid, numprops) {
union acpi_object *key = &props->package.elements[i * 2];
union acpi_object *val = &props->package.elements[i * 2 + 1];
unsigned int k = 1 + numvalid + j * 2; /* index into newprops */
unsigned int v = k + 1;
newprops[1 + j].type = ACPI_TYPE_PACKAGE;
newprops[1 + j].package.count = 2;
newprops[1 + j].package.elements = &newprops[k];
newprops[k].type = ACPI_TYPE_STRING;
newprops[k].string.length = key->string.length;
newprops[k].string.pointer = free_space;
memcpy(free_space, key->string.pointer, key->string.length);
free_space += key->string.length + 1;
newprops[v].type = val->type;
if (val->type == ACPI_TYPE_INTEGER) {
newprops[v].integer.value = val->integer.value;
} else {
newprops[v].buffer.length = val->buffer.length;
newprops[v].buffer.pointer = free_space;
memcpy(free_space, val->buffer.pointer,
val->buffer.length);
free_space += val->buffer.length;
}
j++; /* count valid properties */
}
WARN_ON(free_space != (void *)newprops + newsize);
adev->data.pointer = newprops;
acpi_data_add_props(&adev->data, &apple_prp_guid, newprops);
out_free:
ACPI_FREE(props);
bitmap_free(valid);
}