ACPI: introduce module parameter acpi.aml_debug_output

Introduce module parameter acpi.aml_debug_output.

With acpi.aml_debug_output set, we can get AML debug object output
(Store (AAA, Debug)), even with CONFIG_ACPI_DEBUG cleared.

Together with the runtime custom method mechanism,
we can debug AML code problems without rebuilding the kernel.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

2 files changed, 9 insertions, 1 deletions

diff --git a/drivers/acpi/acpica/acglobal.h b/drivers/acpi/acpica/acglobal.h
index 899d68afc3c5..92122292ef1f 100644
--- a/drivers/acpi/acpica/acglobal.h
+++ b/drivers/acpi/acpica/acglobal.h
@@ -115,7 +115,7 @@ u8 ACPI_INIT_GLOBAL(acpi_gbl_use_default_register_widths, TRUE);
 /*
  * Optionally enable output from the AML Debug Object.
  */
-u8 ACPI_INIT_GLOBAL(acpi_gbl_enable_aml_debug_object, FALSE);
+u32 ACPI_INIT_GLOBAL(acpi_gbl_enable_aml_debug_object, FALSE);
 
 /*
  * Optionally copy the entire DSDT to local memory (instead of simply
diff --git a/drivers/acpi/debugfs.c b/drivers/acpi/debugfs.c
index abfcf9f6e766..7de27d49c4b9 100644
--- a/drivers/acpi/debugfs.c
+++ b/drivers/acpi/debugfs.c
@@ -12,6 +12,14 @@
 #define _COMPONENT              ACPI_SYSTEM_COMPONENT
 ACPI_MODULE_NAME("debugfs");
 
+
+/* /sys/modules/acpi/parameters/aml_debug_output */
+
+module_param_named(aml_debug_output, acpi_gbl_enable_aml_debug_object,
+                   bool, 0644);
+MODULE_PARM_DESC(aml_debug_output,
+                 "To enable/disable the ACPI Debug Object output.");
+
 /* /sys/kernel/debug/acpi/custom_method */
 
 static ssize_t cm_write(struct file *file, const char __user * user_buf,