From ff8651237f39cea60dc89b2d9f25d9ede3fc82c0 Mon Sep 17 00:00:00 2001 From: Gabriele Mazzotta Date: Tue, 24 May 2016 22:53:08 +0200 Subject: [PATCH] dell-rbtn: Ignore ACPI notifications if device is suspended MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Some BIOSes unconditionally send an ACPI notification to RBTN when the system is resuming from suspend. This makes dell-rbtn send an input event to userspace as if a function key was pressed. Prevent this by ignoring all the notifications received while the device is suspended. Link: https://bugzilla.kernel.org/show_bug.cgi?id=106031 Signed-off-by: Gabriele Mazzotta Tested-by: Alex Hung Reviewed-by: Pali Rohár Cc: stable@vger.kernel.org Signed-off-by: Darren Hart --- drivers/platform/x86/dell-rbtn.c | 56 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) diff --git a/drivers/platform/x86/dell-rbtn.c b/drivers/platform/x86/dell-rbtn.c index b51a200..dcd9f40 100644 --- a/drivers/platform/x86/dell-rbtn.c +++ b/drivers/platform/x86/dell-rbtn.c @@ -28,6 +28,7 @@ struct rbtn_data { enum rbtn_type type; struct rfkill *rfkill; struct input_dev *input_dev; + bool suspended; }; @@ -235,9 +236,55 @@ static const struct acpi_device_id rbtn_ids[] = { { "", 0 }, }; +#ifdef CONFIG_PM_SLEEP +static void ACPI_SYSTEM_XFACE rbtn_clear_suspended_flag(void *context) +{ + struct rbtn_data *rbtn_data = context; + + rbtn_data->suspended = false; +} + +static int rbtn_suspend(struct device *dev) +{ + struct acpi_device *device = to_acpi_device(dev); + struct rbtn_data *rbtn_data = acpi_driver_data(device); + + rbtn_data->suspended = true; + + return 0; +} + +static int rbtn_resume(struct device *dev) +{ + struct acpi_device *device = to_acpi_device(dev); + struct rbtn_data *rbtn_data = acpi_driver_data(device); + acpi_status status; + + /* + * Upon resume, some BIOSes send an ACPI notification thet triggers + * an unwanted input event. In order to ignore it, we use a flag + * that we set at suspend and clear once we have received the extra + * ACPI notification. Since ACPI notifications are delivered + * asynchronously to drivers, we clear the flag from the workqueue + * used to deliver the notifications. This should be enough + * to have the flag cleared only after we received the extra + * notification, if any. + */ + status = acpi_os_execute(OSL_NOTIFY_HANDLER, + rbtn_clear_suspended_flag, rbtn_data); + if (ACPI_FAILURE(status)) + rbtn_clear_suspended_flag(rbtn_data); + + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(rbtn_pm_ops, rbtn_suspend, rbtn_resume); + static struct acpi_driver rbtn_driver = { .name = "dell-rbtn", .ids = rbtn_ids, + .drv.pm = &rbtn_pm_ops, .ops = { .add = rbtn_add, .remove = rbtn_remove, @@ -399,6 +446,15 @@ static void rbtn_notify(struct acpi_device *device, u32 event) { struct rbtn_data *rbtn_data = device->driver_data; + /* + * Some BIOSes send a notification at resume. + * Ignore it to prevent unwanted input events. + */ + if (rbtn_data->suspended) { + dev_dbg(&device->dev, "ACPI notification ignored\n"); + return; + } + if (event != 0x80) { dev_info(&device->dev, "Received unknown event (0x%x)\n", event); -- 2.7.4