[PATCH v2 4/5] ACPI: button: Always notify kernel space using _LID returning value

[Lv Zheng <lv.zheng@intel.com>]

Both nouveau and i915, the only 2 kernel space lid notification listeners,
invoke acpi_lid_open() API to obtain _LID returning value instead of using
the notified value.

So this patch moves this logic from listeners to lid driver, always notify
kernel space listeners using _LID returning value.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
---
 drivers/acpi/button.c | 31 ++++++++++++++++++++-----------
 1 file changed, 20 insertions(+), 11 deletions(-)

diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c
index b91ff86..7ff3a75 100644
--- a/drivers/acpi/button.c
+++ b/drivers/acpi/button.c
@@ -119,6 +119,9 @@ static u8 lid_init_state = ACPI_BUTTON_LID_INIT_OPEN;
 static unsigned long lid_report_interval __read_mostly = 500;
 module_param(lid_report_interval, ulong, 0644);
 MODULE_PARM_DESC(lid_report_interval, "Interval (ms) between lid key events");
+static bool lid_fake_events __read_mostly = true;
+module_param(lid_fake_events, bool, 0644);
+MODULE_PARM_DESC(lid_fake_events, "Deliver fake events to kernel drivers");
 
 /* --------------------------------------------------------------------------
                               FS Interface (/proc)
@@ -139,7 +142,8 @@ static int acpi_lid_evaluate_state(struct acpi_device *device)
 	return lid_state ? 1 : 0;
 }
 
-static void acpi_lid_notify_state(struct acpi_device *device, int state)
+static void acpi_lid_notify_state(struct acpi_device *device,
+				  int state, bool bios_notify)
 {
 	struct acpi_button *button = acpi_driver_data(device);
 	ktime_t next_report;
@@ -219,7 +223,11 @@ static void acpi_lid_notify_state(struct acpi_device *device, int state)
 	if (state)
 		pm_wakeup_event(&device->dev, 0);
 
-	atomic_notifier_call_chain(&acpi_lid_notifier, state, device);
+	if (bios_notify)
+		atomic_notifier_call_chain(&acpi_lid_notifier, state, device);
+	else if (lid_fake_events)
+		atomic_notifier_call_chain(&acpi_lid_notifier,
+			acpi_lid_evaluate_state(device), device);
 }
 
 static int acpi_button_state_seq_show(struct seq_file *seq, void *offset)
@@ -349,7 +357,8 @@ int acpi_lid_open(void)
 }
 EXPORT_SYMBOL(acpi_lid_open);
 
-static int acpi_lid_update_state(struct acpi_device *device)
+static int acpi_lid_update_state(struct acpi_device *device,
+				 bool bios_notify)
 {
 	int state;
 
@@ -357,7 +366,7 @@ static int acpi_lid_update_state(struct acpi_device *device)
 	if (state < 0)
 		return state;
 
-	acpi_lid_notify_state(device, state);
+	acpi_lid_notify_state(device, state, bios_notify);
 	return 0;
 }
 
@@ -365,13 +374,13 @@ static void acpi_lid_initialize_state(struct acpi_device *device)
 {
 	switch (lid_init_state) {
 	case ACPI_BUTTON_LID_INIT_OPEN:
-		(void)acpi_lid_notify_state(device, 1);
+		(void)acpi_lid_notify_state(device, 1, false);
 		break;
 	case ACPI_BUTTON_LID_INIT_CLOSE:
-		(void)acpi_lid_notify_state(device, 0);
+		(void)acpi_lid_notify_state(device, 0, false);
 		break;
 	case ACPI_BUTTON_LID_INIT_METHOD:
-		(void)acpi_lid_update_state(device);
+		(void)acpi_lid_update_state(device, false);
 		break;
 	case ACPI_BUTTON_LID_INIT_IGNORE:
 	default:
@@ -391,7 +400,7 @@ static void acpi_button_notify(struct acpi_device *device, u32 event)
 	case ACPI_BUTTON_NOTIFY_STATUS:
 		input = button->input;
 		if (button->type == ACPI_BUTTON_TYPE_LID) {
-			acpi_lid_update_state(device);
+			acpi_lid_update_state(device, true);
 		} else {
 			int keycode;
 
@@ -555,13 +564,13 @@ static int param_set_lid_init_state(const char *val, struct kernel_param *kp)
 
 	if (!strncmp(val, "open", sizeof("open") - 1)) {
 		lid_init_state = ACPI_BUTTON_LID_INIT_OPEN;
-		pr_info("Notify initial lid state as open\n");
+		pr_info("Notify initial lid state to users space as open and kernel drivers with _LID return value\n");
 	} else if (!strncmp(val, "close", sizeof("close") - 1)) {
 		lid_init_state = ACPI_BUTTON_LID_INIT_CLOSE;
-		pr_info("Notify initial lid state as close\n");
+		pr_info("Notify initial lid state to user space as close and kernel drivers with _LID return value\n");
 	} else if (!strncmp(val, "method", sizeof("method") - 1)) {
 		lid_init_state = ACPI_BUTTON_LID_INIT_METHOD;
-		pr_info("Notify initial lid state with _LID return value\n");
+		pr_info("Notify initial lid state to user/kernel space with _LID return value\n");
 	} else if (!strncmp(val, "ignore", sizeof("ignore") - 1)) {
 		lid_init_state = ACPI_BUTTON_LID_INIT_IGNORE;
 		pr_info("Do not notify initial lid state\n");
-- 
2.7.4