[patch] Reporting the lid status using INPUT

[Richard Hughes <hughsient@gmail.com>]

Len,

* user shuts lid, initiates suspend
{lid is reported down}
* user opens lid, resume completes

But the lid INPUT up event is not sent. This works if you don't initiate
suspend when you shut the lid (blank screen for instance) -- so I know
my hardware is okay.

I see:
input_report_switch(input, SW_LID, !state);

in response to an event, but in a resume hook we should probably do
acpi_evaluate_integer(handle, "_LID", NULL, &state) and then send an
event, just so userspace is aware of what the state of the panel is.

If switch state matches to what input layer thinks it is the event will
not be sent.

Signed-off-by: Richard Hughes <richard@hughsie.com>

--- Begin Message ---

• Subject: No Subject
• From: Richard Hughes <richard@hughsie.com>
• Date: Fri, 15 Jun 2007 15:53:11 +0100

On resume we need to refresh the lid status as we will not get an event if
the lid opening was what triggered the suspend.
This manifests itself in users never getting a "lid open" event when a
suspend happens because of lid close on hardware that supports wake on
lid open. This makes userspace gets very confused indeed.
Patch attached forces a check of the lid status in the resume handler.

Signed-off-by: Richard Hughes <richard@hughsie.com>
---

diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c
index cb4110b..fd3473b 100644
--- a/drivers/acpi/button.c
+++ b/drivers/acpi/button.c
@@ -68,6 +68,7 @@ MODULE_LICENSE("GPL");
 
 static int acpi_button_add(struct acpi_device *device);
 static int acpi_button_remove(struct acpi_device *device, int type);
+static int acpi_button_resume(struct acpi_device *device);
 static int acpi_button_info_open_fs(struct inode *inode, struct file *file);
 static int acpi_button_state_open_fs(struct inode *inode, struct file *file);
 
@@ -77,6 +78,7 @@ static struct acpi_driver acpi_button_driver = {
 	.ids = "button_power,button_sleep,PNP0C0D,PNP0C0C,PNP0C0E",
 	.ops = {
 		.add = acpi_button_add,
+		.resume = acpi_button_resume,
 		.remove = acpi_button_remove,
 	},
 };
@@ -487,6 +489,29 @@ static int acpi_button_remove(struct acpi_device *device, int type)
 	return 0;
 }
 
+/* this is needed to learn about changes made in suspended state */
+static int acpi_button_resume(struct acpi_device *device)
+{
+	struct acpi_button *button;
+	struct acpi_handle *handle;
+	struct input_dev *input;
+	unsigned long state;
+
+	button = device->driver_data;
+	handle = button->device->handle;
+	input = button->input;
+
+	/*
+	 * On resume we send the state; if it matches to what input layer
+	 * thinks then the event will not even reach userspace.
+	 */
+	if (!ACPI_FAILURE(acpi_evaluate_integer(handle, "_LID",
+						NULL, &state)))
+		input_report_switch(input, SW_LID, !state);
+
+	return 0;
+}
+
 static int __init acpi_button_init(void)
 {
 	int result;

--- End Message ---