drm/i915/opregion: debug log about Mailbox #2 for backlight

Start debug logging about the presence of the new Mailbox #2 for
backlight. Actual support is to be added later.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/42fd9cd777c5cc9a8d48db9dd8306924c735918e.1644489329.git.jani.nikula@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_opregion.c b/drivers/gpu/drm/i915/display/intel_opregion.c
index 11de19da0948bbc749593d682a905ccb88a4772b..f31e8c3f8ce0e6ac2a6213bd4539d02aa50f284a 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_opregion.c
+++ b/drivers/gpu/drm/i915/display/intel_opregion.c
@@ -47,10 +47,11 @@
 #define OPREGION_ASLE_EXT_OFFSET       0x1C00
 
 #define OPREGION_SIGNATURE "IntelGraphicsMem"
-#define MBOX_ACPI      (1<<0)
-#define MBOX_SWSCI     (1<<1)
-#define MBOX_ASLE      (1<<2)
-#define MBOX_ASLE_EXT  (1<<4)
+#define MBOX_ACPI              BIT(0)  /* Mailbox #1 */
+#define MBOX_SWSCI             BIT(1)  /* Mailbox #2 (obsolete from v2.x) */
+#define MBOX_ASLE              BIT(2)  /* Mailbox #3 */
+#define MBOX_ASLE_EXT          BIT(4)  /* Mailbox #5 */
+#define MBOX_BACKLIGHT         BIT(5)  /* Mailbox #2 (valid from v3.x) */
 
 struct opregion_header {
        u8 signature[16];
@@ -957,6 +958,10 @@ int intel_opregion_setup(struct drm_i915_private *dev_priv)
                opregion->asle_ext = base + OPREGION_ASLE_EXT_OFFSET;
        }
 
+       if (mboxes & MBOX_BACKLIGHT) {
+               drm_dbg(&dev_priv->drm, "Mailbox #2 for backlight present\n");
+       }
+
        if (intel_load_vbt_firmware(dev_priv) == 0)
                goto out;