HID: fixup quirk for NCR devices

NCR devices are terminally broken by design -- they claim themselves to contain
proper input applications in their HID report descriptor, but behave very badly
if treated in standard way.

According to NCR developers, the devices get confused when queried for reports
in a standard way, rendering them unusable.

NCR is shipping application called "RPSL" that can be used to drive these
devices through hiddev, under the assumption that in-kernel driver doesn't
perform initial report query.
If it does, neither in-kernel nor hiddev-based driver can operate with these
devices any more.

Introduce a quirk that skips the report query for all NCR devices. The previous
NOGET quirk was wrong and had been introduced because I misunderstood the nature
of brokenness of these devices.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>

3 files changed, 4 insertions, 2 deletions

diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index 3f56e9c02e65..0258289f3b3e 100644
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -996,7 +996,8 @@ static int usbhid_start(struct hid_device *hid)
         usbhid->urbctrl->transfer_dma = usbhid->ctrlbuf_dma;
         usbhid->urbctrl->transfer_flags |= (URB_NO_TRANSFER_DMA_MAP | URB_NO_SETUP_DMA_MAP);
 
-        usbhid_init_reports(hid);
+        if (!(hid->quirks & HID_QUIRK_NO_INIT_REPORTS))
+                usbhid_init_reports(hid);
 
         set_bit(HID_STARTED, &usbhid->iofl);
 
diff --git a/drivers/hid/usbhid/hid-quirks.c b/drivers/hid/usbhid/hid-quirks.c
index 2d445b270215..c3b02f59792b 100644
--- a/drivers/hid/usbhid/hid-quirks.c
+++ b/drivers/hid/usbhid/hid-quirks.c
@@ -281,7 +281,7 @@ u32 usbhid_lookup_quirk(const u16 idVendor, const u16 idProduct)
         if (idVendor == USB_VENDOR_ID_NCR &&
                         idProduct >= USB_DEVICE_ID_NCR_FIRST &&
                         idProduct <= USB_DEVICE_ID_NCR_LAST)
-                        return HID_QUIRK_NOGET;
+                        return HID_QUIRK_NO_INIT_REPORTS;
 
         down_read(&dquirks_rwsem);
         bl_entry = usbhid_exists_dquirk(idVendor, idProduct);
diff --git a/include/linux/hid.h b/include/linux/hid.h
index 10f628416740..87093652dda8 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -312,6 +312,7 @@ struct hid_item {
 #define HID_QUIRK_MULTI_INPUT                   0x00000040
 #define HID_QUIRK_SKIP_OUTPUT_REPORTS           0x00010000
 #define HID_QUIRK_FULLSPEED_INTERVAL            0x10000000
+#define HID_QUIRK_NO_INIT_REPORTS               0x20000000
 
 /*
  * This is the global environment of the parser. This information is