On Thu, Jul 7, 2022 at 5:11 PM Stefan Binding sbinding@opensource.cirrus.com wrote:
Add a wrapper function to read the _SUB string from ACPI.
Signed-off-by: Stefan Binding sbinding@opensource.cirrus.com
In case you want to push this through ASoC
Acked-by: Rafael J. Wysocki rafael.j.wysocki@intel.com
Otherwise, I need a maintainer's ACK to apply the second patch.
drivers/acpi/utils.c | 38 ++++++++++++++++++++++++++++++++++++++ include/linux/acpi.h | 6 ++++++ 2 files changed, 44 insertions(+)
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, diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 2a0e95336094..447898685e09 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -762,6 +762,7 @@ static inline u64 acpi_arch_get_root_pointer(void) #endif
int acpi_get_local_address(acpi_handle handle, u32 *addr); +const char *acpi_get_subsystem_id(acpi_handle handle);
#else /* !CONFIG_ACPI */
@@ -1023,6 +1024,11 @@ static inline int acpi_get_local_address(acpi_handle handle, u32 *addr) return -ENODEV; }
+static inline const char *acpi_get_subsystem_id(acpi_handle handle) +{
return ERR_PTR(-ENODEV);+}
static inline int acpi_register_wakeup_handler(int wake_irq, bool (*wakeup)(void *context), void *context) { -- 2.25.1