--- /dev/null
+/*
+ * ACPI device specific properties support.
+ *
+ * Copyright (C) 2014, Intel Corporation
+ * All rights reserved.
+ *
+ * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
+ * Darren Hart <dvhart@linux.intel.com>
+ * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ *
+ * 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/device.h>
+#include <linux/export.h>
+
+#include "internal.h"
+
+/* ACPI _DSD device properties UUID: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */
+static const u8 prp_uuid[16] = {
+ 0x14, 0xd8, 0xff, 0xda, 0xba, 0x6e, 0x8c, 0x4d,
+ 0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01
+};
+
+static bool acpi_property_value_ok(const union acpi_object *value)
+{
+ int j;
+
+ /*
+ * The value must be an integer, a string, a reference, or a package
+ * whose every element must be an integer, a string, or a reference.
+ */
+ switch (value->type) {
+ case ACPI_TYPE_INTEGER:
+ case ACPI_TYPE_STRING:
+ case ACPI_TYPE_LOCAL_REFERENCE:
+ return true;
+
+ case ACPI_TYPE_PACKAGE:
+ for (j = 0; j < value->package.count; j++)
+ switch (value->package.elements[j].type) {
+ case ACPI_TYPE_INTEGER:
+ case ACPI_TYPE_STRING:
+ case ACPI_TYPE_LOCAL_REFERENCE:
+ continue;
+
+ default:
+ return false;
+ }
+
+ return true;
+ }
+ return false;
+}
+
+static bool acpi_properties_format_valid(const union acpi_object *properties)
+{
+ int i;
+
+ for (i = 0; i < properties->package.count; i++) {
+ const union acpi_object *property;
+
+ property = &properties->package.elements[i];
+ /*
+ * Only two elements allowed, the first one must be a string and
+ * the second one has to satisfy certain conditions.
+ */
+ if (property->package.count != 2
+ || property->package.elements[0].type != ACPI_TYPE_STRING
+ || !acpi_property_value_ok(&property->package.elements[1]))
+ return false;
+ }
+ return true;
+}
+
+static void acpi_init_of_compatible(struct acpi_device *adev)
+{
+ const union acpi_object *of_compatible;
+ struct acpi_hardware_id *hwid;
+ bool acpi_of = false;
+ int ret;
+
+ /*
+ * Check if the special PRP0001 ACPI ID is present and in that
+ * case we fill in Device Tree compatible properties for this
+ * device.
+ */
+ list_for_each_entry(hwid, &adev->pnp.ids, list) {
+ if (!strcmp(hwid->id, "PRP0001")) {
+ acpi_of = true;
+ break;
+ }
+ }
+
+ if (!acpi_of)
+ return;
+
+ ret = acpi_dev_get_property_array(adev, "compatible", ACPI_TYPE_STRING,
+ &of_compatible);
+ if (ret) {
+ ret = acpi_dev_get_property(adev, "compatible",
+ ACPI_TYPE_STRING, &of_compatible);
+ if (ret) {
+ acpi_handle_warn(adev->handle,
+ "PRP0001 requires compatible property\n");
+ return;
+ }
+ }
+ adev->data.of_compatible = of_compatible;
+}
+
+void acpi_init_properties(struct acpi_device *adev)
+{
+ struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
+ const union acpi_object *desc;
+ acpi_status status;
+ int i;
+
+ status = acpi_evaluate_object_typed(adev->handle, "_DSD", NULL, &buf,
+ ACPI_TYPE_PACKAGE);
+ if (ACPI_FAILURE(status))
+ return;
+
+ desc = buf.pointer;
+ if (desc->package.count % 2)
+ goto fail;
+
+ /* Look for the device properties UUID. */
+ for (i = 0; i < desc->package.count; i += 2) {
+ const union acpi_object *uuid, *properties;
+
+ uuid = &desc->package.elements[i];
+ properties = &desc->package.elements[i + 1];
+
+ /*
+ * The first element must be a UUID and the second one must be
+ * a package.
+ */
+ if (uuid->type != ACPI_TYPE_BUFFER || uuid->buffer.length != 16
+ || properties->type != ACPI_TYPE_PACKAGE)
+ break;
+
+ if (memcmp(uuid->buffer.pointer, prp_uuid, sizeof(prp_uuid)))
+ continue;
+
+ /*
+ * We found the matching UUID. Now validate the format of the
+ * package immediately following it.
+ */
+ if (!acpi_properties_format_valid(properties))
+ break;
+
+ adev->data.pointer = buf.pointer;
+ adev->data.properties = properties;
+
+ acpi_init_of_compatible(adev);
+ return;
+ }
+
+ fail:
+ dev_warn(&adev->dev, "Returned _DSD data is not valid, skipping\n");
+ ACPI_FREE(buf.pointer);
+}
+
+void acpi_free_properties(struct acpi_device *adev)
+{
+ ACPI_FREE((void *)adev->data.pointer);
+ adev->data.of_compatible = NULL;
+ adev->data.pointer = NULL;
+ adev->data.properties = NULL;
+}
+
+/**
+ * acpi_dev_get_property - return an ACPI property with given name
+ * @adev: ACPI device to get property
+ * @name: Name of the property
+ * @type: Expected property type
+ * @obj: Location to store the property value (if not %NULL)
+ *
+ * Look up a property with @name and store a pointer to the resulting ACPI
+ * object at the location pointed to by @obj if found.
+ *
+ * Callers must not attempt to free the returned objects. These objects will be
+ * freed by the ACPI core automatically during the removal of @adev.
+ *
+ * Return: %0 if property with @name has been found (success),
+ * %-EINVAL if the arguments are invalid,
+ * %-ENODATA if the property doesn't exist,
+ * %-EPROTO if the property value type doesn't match @type.
+ */
+int acpi_dev_get_property(struct acpi_device *adev, const char *name,
+ acpi_object_type type, const union acpi_object **obj)
+{
+ const union acpi_object *properties;
+ int i;
+
+ if (!adev || !name)
+ return -EINVAL;
+
+ if (!adev->data.pointer || !adev->data.properties)
+ return -ENODATA;
+
+ properties = adev->data.properties;
+ for (i = 0; i < properties->package.count; i++) {
+ const union acpi_object *propname, *propvalue;
+ const union acpi_object *property;
+
+ property = &properties->package.elements[i];
+
+ propname = &property->package.elements[0];
+ propvalue = &property->package.elements[1];
+
+ if (!strcmp(name, propname->string.pointer)) {
+ if (type != ACPI_TYPE_ANY && propvalue->type != type)
+ return -EPROTO;
+ else if (obj)
+ *obj = propvalue;
+
+ return 0;
+ }
+ }
+ return -ENODATA;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_get_property);
+
+/**
+ * acpi_dev_get_property_array - return an ACPI array property with given name
+ * @adev: ACPI device to get property
+ * @name: Name of the property
+ * @type: Expected type of array elements
+ * @obj: Location to store a pointer to the property value (if not NULL)
+ *
+ * Look up an array property with @name and store a pointer to the resulting
+ * ACPI object at the location pointed to by @obj if found.
+ *
+ * Callers must not attempt to free the returned objects. Those objects will be
+ * freed by the ACPI core automatically during the removal of @adev.
+ *
+ * Return: %0 if array property (package) with @name has been found (success),
+ * %-EINVAL if the arguments are invalid,
+ * %-ENODATA if the property doesn't exist,
+ * %-EPROTO if the property is not a package or the type of its elements
+ * doesn't match @type.
+ */
+int acpi_dev_get_property_array(struct acpi_device *adev, const char *name,
+ acpi_object_type type,
+ const union acpi_object **obj)
+{
+ const union acpi_object *prop;
+ int ret, i;
+
+ ret = acpi_dev_get_property(adev, name, ACPI_TYPE_PACKAGE, &prop);
+ if (ret)
+ return ret;
+
+ if (type != ACPI_TYPE_ANY) {
+ /* Check that all elements are of correct type. */
+ for (i = 0; i < prop->package.count; i++)
+ if (prop->package.elements[i].type != type)
+ return -EPROTO;
+ }
+ if (obj)
+ *obj = prop;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_get_property_array);
+
+/**
+ * acpi_dev_get_property_reference - returns handle to the referenced object
+ * @adev: ACPI device to get property
+ * @name: Name of the property
+ * @index: Index of the reference to return
+ * @args: Location to store the returned reference with optional arguments
+ *
+ * Find property with @name, verifify that it is a package containing at least
+ * one object reference and if so, store the ACPI device object pointer to the
+ * target object in @args->adev. If the reference includes arguments, store
+ * them in the @args->args[] array.
+ *
+ * If there's more than one reference in the property value package, @index is
+ * used to select the one to return.
+ *
+ * Return: %0 on success, negative error code on failure.
+ */
+int acpi_dev_get_property_reference(struct acpi_device *adev,
+ const char *name, size_t index,
+ struct acpi_reference_args *args)
+{
+ const union acpi_object *element, *end;
+ const union acpi_object *obj;
+ struct acpi_device *device;
+ int ret, idx = 0;
+
+ ret = acpi_dev_get_property(adev, name, ACPI_TYPE_ANY, &obj);
+ if (ret)
+ return ret;
+
+ /*
+ * The simplest case is when the value is a single reference. Just
+ * return that reference then.
+ */
+ if (obj->type == ACPI_TYPE_LOCAL_REFERENCE) {
+ if (index)
+ return -EINVAL;
+
+ ret = acpi_bus_get_device(obj->reference.handle, &device);
+ if (ret)
+ return ret;
+
+ args->adev = device;
+ args->nargs = 0;
+ return 0;
+ }
+
+ /*
+ * If it is not a single reference, then it is a package of
+ * references followed by number of ints as follows:
+ *
+ * Package () { REF, INT, REF, INT, INT }
+ *
+ * The index argument is then used to determine which reference
+ * the caller wants (along with the arguments).
+ */
+ if (obj->type != ACPI_TYPE_PACKAGE || index >= obj->package.count)
+ return -EPROTO;
+
+ element = obj->package.elements;
+ end = element + obj->package.count;
+
+ while (element < end) {
+ u32 nargs, i;
+
+ if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
+ return -EPROTO;
+
+ ret = acpi_bus_get_device(element->reference.handle, &device);
+ if (ret)
+ return -ENODEV;
+
+ element++;
+ nargs = 0;
+
+ /* assume following integer elements are all args */
+ for (i = 0; element + i < end; i++) {
+ int type = element[i].type;
+
+ if (type == ACPI_TYPE_INTEGER)
+ nargs++;
+ else if (type == ACPI_TYPE_LOCAL_REFERENCE)
+ break;
+ else
+ return -EPROTO;
+ }
+
+ if (idx++ == index) {
+ args->adev = device;
+ args->nargs = nargs;
+ for (i = 0; i < nargs; i++)
+ args->args[i] = element[i].integer.value;
+
+ return 0;
+ }
+
+ element += nargs;
+ }
+
+ return -EPROTO;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_get_property_reference);
+
+int acpi_dev_prop_get(struct acpi_device *adev, const char *propname,
+ void **valptr)
+{
+ return acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
+ (const union acpi_object **)valptr);
+}
+
+int acpi_dev_prop_read_single(struct acpi_device *adev, const char *propname,
+ enum dev_prop_type proptype, void *val)
+{
+ const union acpi_object *obj;
+ int ret;
+
+ if (!val)
+ return -EINVAL;
+
+ if (proptype >= DEV_PROP_U8 && proptype <= DEV_PROP_U64) {
+ ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_INTEGER, &obj);
+ if (ret)
+ return ret;
+
+ switch (proptype) {
+ case DEV_PROP_U8:
+ if (obj->integer.value > U8_MAX)
+ return -EOVERFLOW;
+ *(u8 *)val = obj->integer.value;
+ break;
+ case DEV_PROP_U16:
+ if (obj->integer.value > U16_MAX)
+ return -EOVERFLOW;
+ *(u16 *)val = obj->integer.value;
+ break;
+ case DEV_PROP_U32:
+ if (obj->integer.value > U32_MAX)
+ return -EOVERFLOW;
+ *(u32 *)val = obj->integer.value;
+ break;
+ default:
+ *(u64 *)val = obj->integer.value;
+ break;
+ }
+ } else if (proptype == DEV_PROP_STRING) {
+ ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_STRING, &obj);
+ if (ret)
+ return ret;
+
+ *(char **)val = obj->string.pointer;
+ } else {
+ ret = -EINVAL;
+ }
+ return ret;
+}
+
+static int acpi_copy_property_array_u8(const union acpi_object *items, u8 *val,
+ size_t nval)
+{
+ int i;
+
+ for (i = 0; i < nval; i++) {
+ if (items[i].type != ACPI_TYPE_INTEGER)
+ return -EPROTO;
+ if (items[i].integer.value > U8_MAX)
+ return -EOVERFLOW;
+
+ val[i] = items[i].integer.value;
+ }
+ return 0;
+}
+
+static int acpi_copy_property_array_u16(const union acpi_object *items,
+ u16 *val, size_t nval)
+{
+ int i;
+
+ for (i = 0; i < nval; i++) {
+ if (items[i].type != ACPI_TYPE_INTEGER)
+ return -EPROTO;
+ if (items[i].integer.value > U16_MAX)
+ return -EOVERFLOW;
+
+ val[i] = items[i].integer.value;
+ }
+ return 0;
+}
+
+static int acpi_copy_property_array_u32(const union acpi_object *items,
+ u32 *val, size_t nval)
+{
+ int i;
+
+ for (i = 0; i < nval; i++) {
+ if (items[i].type != ACPI_TYPE_INTEGER)
+ return -EPROTO;
+ if (items[i].integer.value > U32_MAX)
+ return -EOVERFLOW;
+
+ val[i] = items[i].integer.value;
+ }
+ return 0;
+}
+
+static int acpi_copy_property_array_u64(const union acpi_object *items,
+ u64 *val, size_t nval)
+{
+ int i;
+
+ for (i = 0; i < nval; i++) {
+ if (items[i].type != ACPI_TYPE_INTEGER)
+ return -EPROTO;
+
+ val[i] = items[i].integer.value;
+ }
+ return 0;
+}
+
+static int acpi_copy_property_array_string(const union acpi_object *items,
+ char **val, size_t nval)
+{
+ int i;
+
+ for (i = 0; i < nval; i++) {
+ if (items[i].type != ACPI_TYPE_STRING)
+ return -EPROTO;
+
+ val[i] = items[i].string.pointer;
+ }
+ return 0;
+}
+
+int acpi_dev_prop_read(struct acpi_device *adev, const char *propname,
+ enum dev_prop_type proptype, void *val, size_t nval)
+{
+ const union acpi_object *obj;
+ const union acpi_object *items;
+ int ret;
+
+ if (val && nval == 1) {
+ ret = acpi_dev_prop_read_single(adev, propname, proptype, val);
+ if (!ret)
+ return ret;
+ }
+
+ ret = acpi_dev_get_property_array(adev, propname, ACPI_TYPE_ANY, &obj);
+ if (ret)
+ return ret;
+
+ if (!val)
+ return obj->package.count;
+ else if (nval <= 0)
+ return -EINVAL;
+
+ if (nval > obj->package.count)
+ return -EOVERFLOW;
+
+ items = obj->package.elements;
+ switch (proptype) {
+ case DEV_PROP_U8:
+ ret = acpi_copy_property_array_u8(items, (u8 *)val, nval);
+ break;
+ case DEV_PROP_U16:
+ ret = acpi_copy_property_array_u16(items, (u16 *)val, nval);
+ break;
+ case DEV_PROP_U32:
+ ret = acpi_copy_property_array_u32(items, (u32 *)val, nval);
+ break;
+ case DEV_PROP_U64:
+ ret = acpi_copy_property_array_u64(items, (u64 *)val, nval);
+ break;
+ case DEV_PROP_STRING:
+ ret = acpi_copy_property_array_string(items, (char **)val, nval);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+ return ret;
+}
Code Review / kvmfornfv.git / blobdiff