| Message ID | 1408692913-12336-1-git-send-email-vichy.kuo@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Jiri Kosina |
| Headers | show |
On Fri, 22 Aug 2014, CheChun Kuo wrote: > HID IR device will not response to any command send from host when > it is finishing paring and tring to reset itself. During this period of > time, usb_cleaer_halt will be fail and if hid_start_in soon again, we > has the possibility trap in infinite loop. > > Signed-off-by: CheChun Kuo <vichy.kuo@gmail.com> > --- > drivers/hid/usbhid/hid-core.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c > index 79cf503..256b102 100644 > --- a/drivers/hid/usbhid/hid-core.c > +++ b/drivers/hid/usbhid/hid-core.c > @@ -122,7 +122,8 @@ static void hid_reset(struct work_struct *work) > dev_dbg(&usbhid->intf->dev, "clear halt\n"); > rc = usb_clear_halt(hid_to_usb_dev(hid), usbhid->urbin->pipe); > clear_bit(HID_CLEAR_HALT, &usbhid->iofl); > - hid_start_in(hid); > + if (rc == 0) > + hid_start_in(hid); > } I'd need a more detailed explanation for this patch, as I don't understand neither the text in the changelog nor the patch itself. Namely: - which IR devices are showing this behavior? - where does the infinite loop come from? hid_reset() should error out properly if usb_clear_halt() fails and HID_IN_RUNNING flag is not set Thanks,
hi Jiri: 2014-08-22 15:45 GMT+08:00 Jiri Kosina <jkosina@suse.cz>: > On Fri, 22 Aug 2014, CheChun Kuo wrote: > >> HID IR device will not response to any command send from host when >> it is finishing paring and tring to reset itself. During this period of >> time, usb_cleaer_halt will be fail and if hid_start_in soon again, we >> has the possibility trap in infinite loop. >> >> Signed-off-by: CheChun Kuo <vichy.kuo@gmail.com> >> --- >> drivers/hid/usbhid/hid-core.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c >> index 79cf503..256b102 100644 >> --- a/drivers/hid/usbhid/hid-core.c >> +++ b/drivers/hid/usbhid/hid-core.c >> @@ -122,7 +122,8 @@ static void hid_reset(struct work_struct *work) >> dev_dbg(&usbhid->intf->dev, "clear halt\n"); >> rc = usb_clear_halt(hid_to_usb_dev(hid), usbhid->urbin->pipe); >> clear_bit(HID_CLEAR_HALT, &usbhid->iofl); >> - hid_start_in(hid); >> + if (rc == 0) >> + hid_start_in(hid); >> } > > I'd need a more detailed explanation for this patch, as I don't understand > neither the text in the changelog nor the patch itself. Namely: > > - which IR devices are showing this behavior? The USB hid device that will transform IR signal to usb command when user press "volume up/down", "voice recording", etc. > - where does the infinite loop come from? hid_reset() should error out > properly if usb_clear_halt() fails and HID_IN_RUNNING flag is not set Below I briefly draw the timing when this issue happen i) hid_irq_in get URB status as -EPIPE ii) set HID_CLEAR_HALT flag and schedule hid_reset work iii) hid_reset call usb_clear_halt and hid_start_in again iv) if device still doesn't response host command, it will go to i) above and keep looping thanks for your help, -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c index 79cf503..256b102 100644 --- a/drivers/hid/usbhid/hid-core.c +++ b/drivers/hid/usbhid/hid-core.c @@ -122,7 +122,8 @@ static void hid_reset(struct work_struct *work) dev_dbg(&usbhid->intf->dev, "clear halt\n"); rc = usb_clear_halt(hid_to_usb_dev(hid), usbhid->urbin->pipe); clear_bit(HID_CLEAR_HALT, &usbhid->iofl); - hid_start_in(hid); + if (rc == 0) + hid_start_in(hid); } else if (test_bit(HID_RESET_PENDING, &usbhid->iofl)) {
HID IR device will not response to any command send from host when it is finishing paring and tring to reset itself. During this period of time, usb_cleaer_halt will be fail and if hid_start_in soon again, we has the possibility trap in infinite loop. Signed-off-by: CheChun Kuo <vichy.kuo@gmail.com> --- drivers/hid/usbhid/hid-core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)