[PATCH 6.1 231/609] platform/loongarch: laptop: Explicitly reset bl_powered state when suspend

6.1-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Zixing Liu <[email protected]>

commit 91a70492c03040d51b36f595530d6491d5d6c541 upstream.

On EAECIS NL60R with EC firmware version 1.11, resuming from S3 has a
very high chance (>90%) of causing the EC to lose the previous backlight
power state. When this happens, the laptop resumes normally from S3, but
the backlight remains off (when shining on the screen with a flash light,
we can see the screen contents are updating normally).

Since there is no generic way to query the EC's backlight state on
Loongson laptop platforms, assume the worst-case scenario and restart
the backlight power inside the kernel each time the system resumes.

Cc: [email protected]
Fixes: 53c762b47f72 ("platform/loongarch: laptop: Add backlight power control support")
Tested-by: Yao Zi <[email protected]>
Tested-by: Xi Ruoyao <[email protected]>
Signed-off-by: Zixing Liu <[email protected]>
Signed-off-by: Huacai Chen <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 drivers/platform/loongarch/loongson-laptop.c |    1 +
 1 file changed, 1 insertion(+)

--- a/drivers/platform/loongarch/loongson-laptop.c
+++ b/drivers/platform/loongarch/loongson-laptop.c
@@ -189,6 +189,7 @@ static int __init setup_acpi_notify(stru
 
 static int loongson_hotkey_suspend(struct device *dev)
 {
+	bl_powered = false;
 	return 0;
 }