[PATCH 10/11] ACPI: property: Add support for parsing buffer property UUID

Sakari Ailus
2022-05-06T12:58:42Z

Add support for newly added buffer property UUID, as defined in the DSD
guide.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
---
drivers/acpi/property.c | 141 ++++++++++++++++++++++++++++++++++++----
include/acpi/acpi_bus.h | 3 +-
include/linux/acpi.h | 2 +-
3 files changed, 131 insertions(+), 15 deletions(-)

diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
index 2205612fd6e98..d3f6d95e0fb19 100644
--- a/drivers/acpi/property.c
+++ b/drivers/acpi/property.c
@@ -55,14 +55,19 @@ static const guid_t ads_guid =
GUID_INIT(0xdbb8e3e6, 0x5886, 0x4ba6,
0x87, 0x95, 0x13, 0x19, 0xf5, 0x2a, 0x96, 0x6b);

+static const guid_t buffer_prop_guid =
+ GUID_INIT(0xedb12dd0, 0x363d, 0x4085,
+ 0xa3, 0xd2, 0x49, 0x52, 0x2c, 0xa1, 0x60, 0xc4);
+
static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
- const union acpi_object *desc,
+ union acpi_object *desc,
struct acpi_device_data *data,
struct fwnode_handle *parent);
-static bool acpi_extract_properties(const union acpi_object *desc,
+static bool acpi_extract_properties(acpi_handle handle,
+ union acpi_object *desc,
struct acpi_device_data *data);

-static bool acpi_nondev_subnode_extract(const union acpi_object *desc,
+static bool acpi_nondev_subnode_extract(union acpi_object *desc,
acpi_handle handle,
const union acpi_object *link,
struct list_head *list,
@@ -81,7 +86,7 @@ static bool acpi_nondev_subnode_extract(const union acpi_object *desc,
INIT_LIST_HEAD(&dn->data.properties);
INIT_LIST_HEAD(&dn->data.subnodes);

- result = acpi_extract_properties(desc, &dn->data);
+ result = acpi_extract_properties(handle, desc, &dn->data);

if (handle) {
acpi_handle scope;
@@ -156,7 +161,7 @@ static bool acpi_nondev_subnode_ok(acpi_handle scope,
}

static bool acpi_add_nondev_subnodes(acpi_handle scope,
- const union acpi_object *links,
+ union acpi_object *links,
struct list_head *list,
struct fwnode_handle *parent)
{
@@ -164,7 +169,7 @@ static bool acpi_add_nondev_subnodes(acpi_handle scope,
int i;

for (i = 0; i < links->package.count; i++) {
- const union acpi_object *link, *desc;
+ union acpi_object *link, *desc;
acpi_handle handle;
bool result;

@@ -204,7 +209,7 @@ static bool acpi_add_nondev_subnodes(acpi_handle scope,
}

static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,
- const union acpi_object *desc,
+ union acpi_object *desc,
struct acpi_device_data *data,
struct fwnode_handle *parent)
{
@@ -212,7 +217,8 @@ static bool acpi_enumerate_nondev_subnodes(acpi_handle scope,

/* Look for the ACPI data subnodes GUID. */
for (i = 0; i < desc->package.count; i += 2) {
- const union acpi_object *guid, *links;
+ const union acpi_object *guid;
+ union acpi_object *links;

guid = &desc->package.elements[i];
links = &desc->package.elements[i + 1];
@@ -325,7 +331,7 @@ static bool acpi_is_property_guid(const guid_t *guid)

struct acpi_device_properties *
acpi_data_add_props(struct acpi_device_data *data, const guid_t *guid,
- const union acpi_object *properties)
+ union acpi_object *properties)
{
struct acpi_device_properties *props;

@@ -377,7 +383,103 @@ static int acpi_tie_nondev_subnodes(struct acpi_device_data *data)
return 0;
}

-static bool acpi_extract_properties(const union acpi_object *desc,
+static void acpi_data_add_buffer_props(acpi_handle handle,
+ struct acpi_device_data *data,
+ union acpi_object *properties)
+{
+ struct acpi_device_properties *props;
+ union acpi_object *package;
+ size_t alloc_size;
+ unsigned int i;
+ u32 *count;
+
+ if (check_mul_overflow((size_t)properties->package.count,
+ sizeof(*package) + sizeof(void *),
+ &alloc_size) ||
+ check_add_overflow(sizeof(*props) + sizeof(*package), alloc_size,
+ &alloc_size)) {
+ acpi_handle_warn(handle,
+ "can't allocate memory for %u buffer props",
+ properties->package.count);
+ return;
+ }
+
+ props = kvzalloc(alloc_size, GFP_KERNEL);
+ if (!props)
+ return;
+
+ props->guid = &buffer_prop_guid;
+ props->bufs = (void *)(props + 1);
+ props->properties = (void *)(props->bufs + properties->package.count);
+
+ /* Outer package */
+ package = props->properties;
+ package->type = ACPI_TYPE_PACKAGE;
+ package->package.elements = package + 1;
+ count = &package->package.count;
+ *count = 0;
+
+ /* Inner packages */
+ package++;
+
+ for (i = 0; i < properties->package.count; i++) {
+ struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
+ union acpi_object *property = &properties->package.elements[i];
+ union acpi_object *prop, *obj, *buf_obj;
+ acpi_status status;
+
+ if (property->type != ACPI_TYPE_PACKAGE ||
+ property->package.count != 2) {
+ acpi_handle_warn(handle,
+ "buffer property %u has %u entries\n",
+ i, property->package.count);
+ continue;
+ }
+
+ prop = &property->package.elements[0];
+ obj = &property->package.elements[1];
+
+ if (prop->type != ACPI_TYPE_STRING ||
+ obj->type != ACPI_TYPE_STRING) {
+ acpi_handle_warn(handle,
+ "wrong object types %u and %u\n",
+ prop->type, obj->type);
+ continue;
+ }
+
+ status = acpi_evaluate_object_typed(handle, obj->string.pointer,
+ NULL, &buf,
+ ACPI_TYPE_BUFFER);
+ if (ACPI_FAILURE(status)) {
+ acpi_handle_warn(handle,
+ "can't evaluate \"%s\" as buffer\n",
+ obj->string.pointer);
+ continue;
+ }
+
+ package->type = ACPI_TYPE_PACKAGE;
+ package->package.elements = prop;
+ package->package.count = 2;
+
+ buf_obj = buf.pointer;
+
+ /* Replace the string object with a buffer object */
+ obj->type = ACPI_TYPE_BUFFER;
+ obj->buffer.length = buf_obj->buffer.length;
+ obj->buffer.pointer = buf_obj->buffer.pointer;
+
+ props->bufs[i] = buf.pointer;
+ package++;
+ (*count)++;
+ }
+
+ if (*count)
+ list_add(&props->list, &data->properties);
+ else
+ kvfree(props);
+}
+
+static bool acpi_extract_properties(acpi_handle scope, union acpi_object *desc,
struct acpi_device_data *data)
{
int i;
@@ -387,7 +489,8 @@ static bool acpi_extract_properties(const union acpi_object *desc,

/* Look for the device properties GUID. */
for (i = 0; i < desc->package.count; i += 2) {
- const union acpi_object *guid, *properties;
+ const union acpi_object *guid;
+ union acpi_object *properties;

guid = &desc->package.elements[i];
properties = &desc->package.elements[i + 1];
@@ -401,6 +504,12 @@ static bool acpi_extract_properties(const union acpi_object *desc,
properties->type != ACPI_TYPE_PACKAGE)
break;

+ if (guid_equal((guid_t *)guid->buffer.pointer,
+ &buffer_prop_guid)) {
+ acpi_data_add_buffer_props(scope, data, properties);
+ continue;
+ }
+
if (!acpi_is_property_guid((guid_t *)guid->buffer.pointer))
continue;

@@ -447,7 +556,7 @@ void acpi_init_properties(struct acpi_device *adev)
if (ACPI_FAILURE(status))
goto out;

- if (acpi_extract_properties(buf.pointer, &adev->data)) {
+ if (acpi_extract_properties(adev->handle, buf.pointer, &adev->data)) {
adev->data.pointer = buf.pointer;
if (acpi_of)
acpi_init_of_compatible(adev);
@@ -477,8 +586,14 @@ static void acpi_free_device_properties(struct list_head *list)
struct acpi_device_properties *props, *tmp;

list_for_each_entry_safe(props, tmp, list, list) {
+ u32 i;
+
list_del(&props->list);
- kfree(props);
+ /* Buffer data properties were separately allocated */
+ if (props->bufs)
+ for (i = 0; i < props->properties->package.count; i++)
+ ACPI_FREE(props->bufs[i]);
+ kvfree(props);
}
}

diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index b44aaffedb914..8df984013ee71 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -344,8 +344,9 @@ struct acpi_device_physical_node {

struct acpi_device_properties {
const guid_t *guid;
- const union acpi_object *properties;
+ union acpi_object *properties;
struct list_head list;
+ void **bufs;
};

/* ACPI Device Specific Data (_DSD) */
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index d7136d13aa442..a411bae44b7e2 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -1204,7 +1204,7 @@ static inline bool acpi_dev_has_props(const struct acpi_device *adev)

struct acpi_device_properties *
acpi_data_add_props(struct acpi_device_data *data, const guid_t *guid,
- const union acpi_object *properties);
+ union acpi_object *properties);

int acpi_node_prop_get(const struct fwnode_handle *fwnode, const char *propname,
void **valptr);
--
2.30.2