Ming Lei <ming.lei@xxxxxxxxxxxxx> writes: > If suspend callback fails in system sleep context, usb core will > ignore the failure and let system sleep go ahead further, so > this patch doesn't recover device under this situation. > > Cc: Bjørn Mork <bjorn@xxxxxxx> > Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxxxxx> > --- > drivers/net/usb/cdc_mbim.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/usb/cdc_mbim.c b/drivers/net/usb/cdc_mbim.c > index 248d2dc..ec58c2c 100644 > --- a/drivers/net/usb/cdc_mbim.c > +++ b/drivers/net/usb/cdc_mbim.c > @@ -338,7 +338,7 @@ static int cdc_mbim_suspend(struct usb_interface *intf, pm_message_t message) > > if (intf == ctx->control && info->subdriver && info->subdriver->suspend) > ret = info->subdriver->suspend(intf, message); > - if (ret < 0) > + if (ret < 0 && PMSG_IS_AUTO(message)) > usbnet_resume(intf); > > error: This condition will never happen because the subdriver callback always return 0 if !PMSG_IS_AUTO(message), so adding anything here is purely for documentation purposes. That is OK for me. But I do not see any point adding incomplete or wrong documentation. The above is incomplete because it ignores the failure and still return an error. And it is wrong because we ignore an error we cannot possibly handle in resume. Only the subdriver can do that, which is why we must delegate this to the subdriver. I believe the correct here is to document the fact that we require the subdriver->suspend() callback to always return 0 if !PMSG_IS_AUTO(message). That is best done with a comment. No need to add any redundant code. Bjørn -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
