drm/privacy_screen_x86: Add entry for ChromeOS privacy-screen

Add a static entry in the x86 table, to detect and wait for
privacy-screen on some ChromeOS platforms.

Please note that this means that if CONFIG_CHROMEOS_PRIVACY_SCREEN is
enabled, and if "GOOG0010" device is found in ACPI, then the i915 probe
shall return EPROBE_DEFER until a platform driver actually registers the
privacy-screen: https://hansdegoede.livejournal.com/25948.html

Signed-off-by: Rajat Jain <rajatja@google.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220107190208.95479-3-rajatja@google.com

diff --git a/drivers/gpu/drm/drm_privacy_screen_x86.c b/drivers/gpu/drm/drm_privacy_screen_x86.c
index a2cafb294ca6a1990410e8ee8014fdca55fc4677..88802cd7a1ee39392f8704002a79a7106f9f364f 100644 (file)
--- a/drivers/gpu/drm/drm_privacy_screen_x86.c
+++ b/drivers/gpu/drm/drm_privacy_screen_x86.c
@@ -47,6 +47,13 @@ static bool __init detect_thinkpad_privacy_screen(void)
 }
 #endif
 
+#if IS_ENABLED(CONFIG_CHROMEOS_PRIVACY_SCREEN)
+static bool __init detect_chromeos_privacy_screen(void)
+{
+       return acpi_dev_present("GOOG0010", NULL, -1);
+}
+#endif
+
 static const struct arch_init_data arch_init_data[] __initconst = {
 #if IS_ENABLED(CONFIG_THINKPAD_ACPI)
        {
@@ -58,6 +65,16 @@ static const struct arch_init_data arch_init_data[] __initconst = {
                .detect = detect_thinkpad_privacy_screen,
        },
 #endif
+#if IS_ENABLED(CONFIG_CHROMEOS_PRIVACY_SCREEN)
+       {
+               .lookup = {
+                       .dev_id = NULL,
+                       .con_id = NULL,
+                       .provider = "privacy_screen-GOOG0010:00",
+               },
+               .detect = detect_chromeos_privacy_screen,
+       },
+#endif
 };
 
 void __init drm_privacy_screen_lookup_init(void)