On 12/9/2015 8:45 PM, Doug Anderson wrote: > John, > > On Wed, Dec 2, 2015 at 11:15 AM, John Youn <John.Youn@xxxxxxxxxxxx> wrote: >> The delay for force mode is only 25ms according to the databook. >> >> Signed-off-by: John Youn <johnyoun@xxxxxxxxxxxx> >> --- >> drivers/usb/dwc2/core.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/usb/dwc2/core.c b/drivers/usb/dwc2/core.c >> index 91d63a8..a6fddbf 100644 >> --- a/drivers/usb/dwc2/core.c >> +++ b/drivers/usb/dwc2/core.c >> @@ -552,7 +552,7 @@ int dwc2_core_reset_and_force_mode(struct dwc2_hsotg *hsotg) >> * NOTE: This long sleep is _very_ important, otherwise the core will >> * not stay in host mode after a connector ID change! >> */ >> - usleep_range(150000, 160000); >> + usleep_range(25000, 50000); > > This seems to work for me. At least I've done reboots and not noticed > any problems. :-P > > Personally I'd suggest tightening the range to something like (25000, > 30000) or even replacing with "msleep(25)". From past experience I've > found that usleep_range() nearly always picks the largest value you > gave it. That's supposed to be for power savings for things you do > all the time. For a rare thing like a reset it's just a waste of > time. I'm not sure why it was usleep_range or why the delay was so large. I was being conservative in the change but I think I'll change it as you suggest to msleep(25) and if issues come it we can deal with them. Regards, John -- 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
