[RFC 07/13] acpi/x86: s2idle: call Display On/Off as part of callbacks

[Antheas Kapenekakis]

Move the Display On/Off notifications into dedicated callbacks that gate
the ACPI mutex, so they can be called outside of the suspend path.

Co-developed-by: Mario Limonciello <mario.limonciello at amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello at amd.com>
Signed-off-by: Antheas Kapenekakis <lkml at antheas.dev>
---
 drivers/acpi/x86/s2idle.c | 67 +++++++++++++++++++++++++++++----------
 1 file changed, 51 insertions(+), 16 deletions(-)

diff --git a/drivers/acpi/x86/s2idle.c b/drivers/acpi/x86/s2idle.c
index 7391f87f3aa0..8b39e3b12ec0 100644
--- a/drivers/acpi/x86/s2idle.c
+++ b/drivers/acpi/x86/s2idle.c
@@ -60,6 +60,7 @@ static int lps0_dsm_func_mask;
 static guid_t lps0_dsm_guid_microsoft;
 static int lps0_dsm_func_mask_microsoft;
 static int lps0_dsm_state;
+static bool lsp0_dsm_in_display_off;
 
 /* Device constraint entry structure */
 struct lpi_device_info {
@@ -539,17 +540,18 @@ static struct acpi_scan_handler lps0_handler = {
 	.attach = lps0_device_attach,
 };
 
-int acpi_s2idle_prepare_late(void)
+static int acpi_s2idle_display_off(void)
 {
-	struct acpi_s2idle_dev_ops *handler;
-
 	if (!lps0_device_handle || sleep_no_lps0)
 		return 0;
 
-	if (pm_debug_messages_on)
-		lpi_check_constraints();
+	if (WARN_ON(lsp0_dsm_in_display_off))
+		return -EINVAL;
+
+	lsp0_dsm_in_display_off = true;
+	acpi_scan_lock_acquire();
 
-	/* Screen off */
+	/* Display off */
 	if (lps0_dsm_func_mask > 0)
 		acpi_sleep_run_lps0_dsm(acpi_s2idle_vendor_amd() ?
 					ACPI_LPS0_DISPLAY_OFF_AMD :
@@ -560,6 +562,47 @@ int acpi_s2idle_prepare_late(void)
 		acpi_sleep_run_lps0_dsm(ACPI_LPS0_DISPLAY_OFF,
 				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
 
+	acpi_scan_lock_release();
+
+	return 0;
+}
+
+static int acpi_s2idle_display_on(void)
+{
+	if (!lps0_device_handle || sleep_no_lps0)
+		return 0;
+
+	if (WARN_ON(!lsp0_dsm_in_display_off))
+		return -EINVAL;
+
+	lsp0_dsm_in_display_off = false;
+	acpi_scan_lock_acquire();
+
+	/* Display on */
+	if (lps0_dsm_func_mask_microsoft > 0)
+		acpi_sleep_run_lps0_dsm(ACPI_LPS0_DISPLAY_ON,
+				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
+	if (lps0_dsm_func_mask > 0)
+		acpi_sleep_run_lps0_dsm(acpi_s2idle_vendor_amd() ?
+					ACPI_LPS0_DISPLAY_ON_AMD :
+					ACPI_LPS0_DISPLAY_ON,
+					lps0_dsm_func_mask, lps0_dsm_guid);
+
+	acpi_scan_lock_release();
+
+	return 0;
+}
+
+int acpi_s2idle_prepare_late(void)
+{
+	struct acpi_s2idle_dev_ops *handler;
+
+	if (!lps0_device_handle || sleep_no_lps0)
+		return 0;
+
+	if (pm_debug_messages_on)
+		lpi_check_constraints();
+
 	/* LPS0 entry */
 	if (lps0_dsm_func_mask > 0 && acpi_s2idle_vendor_amd())
 		acpi_sleep_run_lps0_dsm(ACPI_LPS0_ENTRY_AMD,
@@ -623,19 +666,10 @@ void acpi_s2idle_restore_early(void)
 		acpi_sleep_run_lps0_dsm(ACPI_LPS0_MS_EXIT,
 				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
 	}
-
-	/* Screen on */
-	if (lps0_dsm_func_mask_microsoft > 0)
-		acpi_sleep_run_lps0_dsm(ACPI_LPS0_DISPLAY_ON,
-				lps0_dsm_func_mask_microsoft, lps0_dsm_guid_microsoft);
-	if (lps0_dsm_func_mask > 0)
-		acpi_sleep_run_lps0_dsm(acpi_s2idle_vendor_amd() ?
-						ACPI_LPS0_DISPLAY_ON_AMD :
-						ACPI_LPS0_DISPLAY_ON,
-					lps0_dsm_func_mask, lps0_dsm_guid);
 }
 
 static const struct platform_s2idle_ops acpi_s2idle_ops_lps0 = {
+	.display_off = acpi_s2idle_display_off,
 	.begin = acpi_s2idle_begin,
 	.prepare = acpi_s2idle_prepare,
 	.prepare_late = acpi_s2idle_prepare_late,
@@ -644,6 +678,7 @@ static const struct platform_s2idle_ops acpi_s2idle_ops_lps0 = {
 	.restore_early = acpi_s2idle_restore_early,
 	.restore = acpi_s2idle_restore,
 	.end = acpi_s2idle_end,
+	.display_on = acpi_s2idle_display_on,
 };
 
 void __init acpi_s2idle_setup(void)
-- 
2.47.0