[PATCH AUTOSEL 4.4 03/37] Input: atmel_mxt_ts - disable IRQ across suspend

[PATCH AUTOSEL 4.4 03/37] Input: atmel_mxt_ts - disable IRQ across suspend

[Sasha Levin]

From: Evan Green <evgreen@chromium.org>

[ Upstream commit 463fa44eec2fef50d111ed0199cf593235065c04 ]

Across suspend and resume, we are seeing error messages like the following:

atmel_mxt_ts i2c-PRP0001:00: __mxt_read_reg: i2c transfer failed (-121)
atmel_mxt_ts i2c-PRP0001:00: Failed to read T44 and T5 (-121)

This occurs because the driver leaves its IRQ enabled. Upon resume, there
is an IRQ pending, but the interrupt is serviced before both the driver and
the underlying I2C bus have been resumed. This causes EREMOTEIO errors.

Disable the IRQ in suspend, and re-enable it on resume. If there are cases
where the driver enters suspend with interrupts disabled, that's a bug we
should fix separately.

Signed-off-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/input/touchscreen/atmel_mxt_ts.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index be2f2521c1c50..d955841da57d6 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -2701,6 +2701,8 @@ static int __maybe_unused mxt_suspend(struct device *dev)
 
 	mutex_unlock(&input_dev->mutex);
 
+	disable_irq(data->irq);
+
 	return 0;
 }
 
@@ -2713,6 +2715,8 @@ static int __maybe_unused mxt_resume(struct device *dev)
 	if (!input_dev)
 		return 0;
 
+	enable_irq(data->irq);
+
 	mutex_lock(&input_dev->mutex);
 
 	if (input_dev->users)
-- 
2.20.1

[PATCH AUTOSEL 4.4 26/37] HID: Improve Windows Precision Touchpad detection.

[Sasha Levin]

From: Blaž Hrastnik <blaz@mxxn.io>

[ Upstream commit 2dbc6f113acd74c66b04bf49fb027efd830b1c5a ]

Per Microsoft spec, usage 0xC5 (page 0xFF) returns a blob containing
data used to verify the touchpad as a Windows Precision Touchpad.

   0x85, REPORTID_PTPHQA,    //    REPORT_ID (PTPHQA)
    0x09, 0xC5,              //    USAGE (Vendor Usage 0xC5)
    0x15, 0x00,              //    LOGICAL_MINIMUM (0)
    0x26, 0xff, 0x00,        //    LOGICAL_MAXIMUM (0xff)
    0x75, 0x08,              //    REPORT_SIZE (8)
    0x96, 0x00, 0x01,        //    REPORT_COUNT (0x100 (256))
    0xb1, 0x02,              //    FEATURE (Data,Var,Abs)

However, some devices, namely Microsoft's Surface line of products
instead implement a "segmented device certification report" (usage 0xC6)
which returns the same report, but in smaller chunks.

    0x06, 0x00, 0xff,        //     USAGE_PAGE (Vendor Defined)
    0x85, REPORTID_PTPHQA,   //     REPORT_ID (PTPHQA)
    0x09, 0xC6,              //     USAGE (Vendor usage for segment #)
    0x25, 0x08,              //     LOGICAL_MAXIMUM (8)
    0x75, 0x08,              //     REPORT_SIZE (8)
    0x95, 0x01,              //     REPORT_COUNT (1)
    0xb1, 0x02,              //     FEATURE (Data,Var,Abs)
    0x09, 0xC7,              //     USAGE (Vendor Usage)
    0x26, 0xff, 0x00,        //     LOGICAL_MAXIMUM (0xff)
    0x95, 0x20,              //     REPORT_COUNT (32)
    0xb1, 0x02,              //     FEATURE (Data,Var,Abs)

By expanding Win8 touchpad detection to also look for the segmented
report, all Surface touchpads are now properly recognized by
hid-multitouch.

Signed-off-by: Blaž Hrastnik <blaz@mxxn.io>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/hid/hid-core.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index c60bb6f8eceb0..7cd9455754636 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -761,6 +761,10 @@ static void hid_scan_feature_usage(struct hid_parser *parser, u32 usage)
 	if (usage == 0xff0000c5 && parser->global.report_count == 256 &&
 	    parser->global.report_size == 8)
 		parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8;
+
+	if (usage == 0xff0000c6 && parser->global.report_count == 1 &&
+	    parser->global.report_size == 8)
+		parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8;
 }
 
 static void hid_scan_collection(struct hid_parser *parser, unsigned type)
-- 
2.20.1