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authorTakashi Iwai <tiwai@suse.de>2022-08-01 15:26:40 +0200
committerTakashi Iwai <tiwai@suse.de>2022-08-01 15:26:40 +0200
commita3b5d4715fd5a839857f8b7be78dff258a8d5a47 (patch)
treeb70d6f050f4831eaba82a60fb443659dc9dfca1c /drivers/acpi
parent9769e44d41a1359b9000ff8458f0f2f66080ebf4 (diff)
parent40d060b8158e26438398bf1132925f666e3b6480 (diff)
Merge tag 'asoc-v5.20-2' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: More updates for v5.20 More updates that came in since the last pull request I sent, a series of driver specific changes: - Support for AMD RPL, some Intel platforms and Mediatek MT8186.
Diffstat (limited to 'drivers/acpi')
-rw-r--r--drivers/acpi/utils.c38
1 files changed, 38 insertions, 0 deletions
diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c
index 3a9773a09e19..5a7b8065e77f 100644
--- a/drivers/acpi/utils.c
+++ b/drivers/acpi/utils.c
@@ -291,6 +291,44 @@ int acpi_get_local_address(acpi_handle handle, u32 *addr)
}
EXPORT_SYMBOL(acpi_get_local_address);
+#define ACPI_MAX_SUB_BUF_SIZE 9
+
+const char *acpi_get_subsystem_id(acpi_handle handle)
+{
+ struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+ union acpi_object *obj;
+ acpi_status status;
+ const char *sub;
+ size_t len;
+
+ status = acpi_evaluate_object(handle, METHOD_NAME__SUB, NULL, &buffer);
+ if (ACPI_FAILURE(status)) {
+ acpi_handle_debug(handle, "Reading ACPI _SUB failed: %#x\n", status);
+ return ERR_PTR(-ENODATA);
+ }
+
+ obj = buffer.pointer;
+ if (obj->type == ACPI_TYPE_STRING) {
+ len = strlen(obj->string.pointer);
+ if (len < ACPI_MAX_SUB_BUF_SIZE && len > 0) {
+ sub = kstrdup(obj->string.pointer, GFP_KERNEL);
+ if (!sub)
+ sub = ERR_PTR(-ENOMEM);
+ } else {
+ acpi_handle_err(handle, "ACPI _SUB Length %zu is Invalid\n", len);
+ sub = ERR_PTR(-ENODATA);
+ }
+ } else {
+ acpi_handle_warn(handle, "Warning ACPI _SUB did not return a string\n");
+ sub = ERR_PTR(-ENODATA);
+ }
+
+ acpi_os_free(buffer.pointer);
+
+ return sub;
+}
+EXPORT_SYMBOL_GPL(acpi_get_subsystem_id);
+
acpi_status
acpi_evaluate_reference(acpi_handle handle,
acpi_string pathname,