Hi Heiner, (and others on the list) Thanks for your quick and detailed response. I am endeavoring to try the patch out now. But I've not built a desktop Linux kernel or kernel modules in about 15 years. Do you have a preferred recipe for applying this patch to an existing distro? Since 'hid-quirks' isn't a module, this means recompiling the entire HID driver, correct? I mostly test against various modern Ubuntu or Raspian flavors of Debian, if that matters. Also, is there a mitigation for users running production distros that doesn't involve a recompile? Thanks, -=Tod > On Nov 10, 2019, at 2:44 a, Heiner Kallweit <hkallweit1@xxxxxxxxx> wrote: > > On 10.11.2019 04:26, Tod E. Kurt wrote: >> HiI >> > Hi Tod, > >> Since you are listed as author of "hid-led.c": >> https://github.com/torvalds/linux/blob/master/drivers/hid/hid-led.c, >> I was wondering if you could offer some insight on an issue I'm seeing. >> I'm a maintainer of "hidapi" and "node-hid", cross-platform C and NodeJs libraries for accessing HID devices, and I'm the creator of the ThingM blink(1) USB LED that "hid-led" controls. >> >> On the distros I've seen (Ubuntu, Raspian) where "hid-led" is enabled, when inserting a blink(1) device, the "hid-led" driver appears to grab the device and remove it from available "hidraw" devices. This makes generic hidraw-based systems (like "hidapi" and the upcoming Chrome WebHID) unable to see the blink(1) >> >> I have tried blacklisting the "hid-led" module but the problem persist. Ffrom dmesg and lsmod the module does appear to not be loaded on reboot. >> >> Any insights on what's going on? Any tips on how to debug this or how to prevent this from occurring? >> > When hid-led was written it was needed to add the LED devices to hid_have_special_driver list. > Else the driver can't take control over the device. Side effect is that even if hid-led > isn't loaded hid-generic can't take control. > I think since e04a0442d33b ("HID: core: remove the absolute need of hid_have_special_driver[]") > it's no longer needed to have the LED devices in hid_have_special_driver. > Could you please test the following patch? If hid-led is loaded is should control the > device, if it's blacklisted hid-generic should have the control. > > > diff --git a/drivers/hid/hid-quirks.c b/drivers/hid/hid-quirks.c > index c50bcd967..bdaab79f7 100644 > --- a/drivers/hid/hid-quirks.c > +++ b/drivers/hid/hid-quirks.c > @@ -419,13 +419,6 @@ static const struct hid_device_id hid_have_special_driver[] = { > #if IS_ENABLED(CONFIG_HID_LCPOWER) > { HID_USB_DEVICE(USB_VENDOR_ID_LCPOWER, USB_DEVICE_ID_LCPOWER_LC1000) }, > #endif > -#if IS_ENABLED(CONFIG_HID_LED) > - { HID_USB_DEVICE(USB_VENDOR_ID_DREAM_CHEEKY, USB_DEVICE_ID_DREAM_CHEEKY_WN) }, > - { HID_USB_DEVICE(USB_VENDOR_ID_DREAM_CHEEKY, USB_DEVICE_ID_DREAM_CHEEKY_FA) }, > - { HID_USB_DEVICE(USB_VENDOR_ID_MICROCHIP, USB_DEVICE_ID_LUXAFOR) }, > - { HID_USB_DEVICE(USB_VENDOR_ID_RISO_KAGAKU, USB_DEVICE_ID_RI_KA_WEBMAIL) }, > - { HID_USB_DEVICE(USB_VENDOR_ID_THINGM, USB_DEVICE_ID_BLINK1) }, > -#endif > #if IS_ENABLED(CONFIG_HID_LENOVO) > { HID_USB_DEVICE(USB_VENDOR_ID_LENOVO, USB_DEVICE_ID_LENOVO_TPKBD) }, > { HID_USB_DEVICE(USB_VENDOR_ID_LENOVO, USB_DEVICE_ID_LENOVO_CUSBKBD) }, > -- > 2.24.0 > >> I can send you blink(1) devices and "hidapi" test programs if you'd like to try to replicate this. >> > Thanks for the offer, I've got a blink(1) already. Just tested the patch with this device > and it worked properly like described above. > >> Thanks! >> -=Tod > > Heiner
