[PATCH] HID: i2c-hid: disable interrupt on suspend

[PATCH] HID: i2c-hid: disable interrupt on suspend

[Mika Westerberg]

When an I2C HID device is powered of during system sleep, as a result of
removing its power resources (by the ACPI core) the interrupt line might go
low as well. This results inadvertent interrupt and wakes the system from
sleep immediately.

To prevent this we disable the device interrupt in the drivers suspend
method and enable it on resume. The device can still wake the system up if
it is wake capable (this also means that not all of its power will be
removed to keep the interrupt line high).

Reported-by: Jerome Blin <jerome.blin@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
---
 drivers/hid/i2c-hid/i2c-hid.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index c1336193b04b..dc8b575477b4 100644
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c
@@ -1073,6 +1073,7 @@ static int i2c_hid_suspend(struct device *dev)
 {
 	struct i2c_client *client = to_i2c_client(dev);
 
+	disable_irq(client->irq);
 	if (device_may_wakeup(&client->dev))
 		enable_irq_wake(client->irq);
 
@@ -1087,6 +1088,7 @@ static int i2c_hid_resume(struct device *dev)
 	int ret;
 	struct i2c_client *client = to_i2c_client(dev);
 
+	enable_irq(client->irq);
 	ret = i2c_hid_hwreset(client);
 	if (ret)
 		return ret;
-- 
1.8.4.3

Re: [PATCH] HID: i2c-hid: disable interrupt on suspend

[Benjamin Tissoires]

On 13/11/13 06:34, Mika Westerberg wrote:
> When an I2C HID device is powered of during system sleep, as a result of
> removing its power resources (by the ACPI core) the interrupt line might go
> low as well. This results inadvertent interrupt and wakes the system from
> sleep immediately.
> 
> To prevent this we disable the device interrupt in the drivers suspend
> method and enable it on resume. The device can still wake the system up if
> it is wake capable (this also means that not all of its power will be
> removed to keep the interrupt line high).
> 
> Reported-by: Jerome Blin <jerome.blin@intel.com>
> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> ---

Jiri, just FYI, I still do not have any final consumer ready i2c-hid
hardware. So I can not test/debug anything related to the suspend-resume.

If Mika tested it properly (which I expect), you may consider pulling
this one.

Cheers,
Benjamin

Re: [PATCH] HID: i2c-hid: disable interrupt on suspend

[Jiri Kosina]

On Mon, 25 Nov 2013, Benjamin Tissoires wrote:

> > When an I2C HID device is powered of during system sleep, as a result of
> > removing its power resources (by the ACPI core) the interrupt line might go
> > low as well. This results inadvertent interrupt and wakes the system from
> > sleep immediately.
> > 
> > To prevent this we disable the device interrupt in the drivers suspend
> > method and enable it on resume. The device can still wake the system up if
> > it is wake capable (this also means that not all of its power will be
> > removed to keep the interrupt line high).
> > 
> > Reported-by: Jerome Blin <jerome.blin@intel.com>
> > Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> > ---
> 
> Jiri, just FYI, I still do not have any final consumer ready i2c-hid
> hardware. So I can not test/debug anything related to the suspend-resume.
> 
> If Mika tested it properly (which I expect), you may consider pulling
> this one.

Understood, thanks guys.

Applied now.

-- 
Jiri Kosina
SUSE Labs