On 18.08.20 at 17:35:33 CEST, Guenter Roeck wrote > On Mon, Aug 17, 2020 at 09:00:40AM +0200, Marius Zachmann wrote: > > Possibly because of the changes in usbhid/hid-core.c the first > > raw input report is not received during ccp_probe function and it will > > timeout. I am not sure, whether this behaviour is expected after > > hid_device_io_start or if I am missing something. > > As a solution this adds msleep(50) to ccp_probe so that all initial > > input reports can be received. > > > > Signed-off-by: Marius Zachmann <mail@xxxxxxxxxxxxxxxxx> > > Let's just ask the HID maintainers. Is this expected, and the correct fix ? > > Thanks, > Guenter > This seems to be a problem with "HID: usbhid: do not sleep when opening device". There is a bug report with some Logitech devices at the correct thread. These drivers also use hid_device_io_start and fail. Seems to me, this is the same problem and I retract this (not so beautiful) fix until this is sorted out. Thanks, Marius > > --- > > v2: > > - fix accidentally deleted comment > > > > --- > > drivers/hwmon/corsair-cpro.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/drivers/hwmon/corsair-cpro.c b/drivers/hwmon/corsair-cpro.c > > index 591929ec217a..c04fac1d820f 100644 > > --- a/drivers/hwmon/corsair-cpro.c > > +++ b/drivers/hwmon/corsair-cpro.c > > @@ -10,6 +10,7 @@ > > > > #include <linux/bitops.h> > > #include <linux/completion.h> > > +#include <linux/delay.h> > > #include <linux/hid.h> > > #include <linux/hwmon.h> > > #include <linux/kernel.h> > > @@ -513,6 +514,7 @@ static int ccp_probe(struct hid_device *hdev, const struct hid_device_id *id) > > init_completion(&ccp->wait_input_report); > > > > hid_device_io_start(hdev); > > + msleep(50); /* wait before events can be received */ > > > > /* temp and fan connection status only updates when device is powered on */ > > ret = get_temp_cnct(ccp); > > -- > > 2.28.0 >
