Hi Eric, > Eric Anholt <eric@xxxxxxxxxx> hat am 22. August 2016 um 19:57 geschrieben: > > > Stefan Wahren <stefan.wahren@xxxxxxxx> writes: > > > In case dr_mode isn't passed via DT, the dwc2 defaults to OTG mode. > > But all Raspberry Pi boards here are designed only for host mode. > > So fix this issue by providing a dtsi file which set the dr_mode > > to host. > > Can you explain what change this should cause for these boards? Is it > just going to drop this message from dmesg: > > dwc2 3f980000.usb: Configuration mismatch. dr_mode forced to host IMO it isn't a message which could be ignored. The dwc2 tries to detected the USB role from compile configuration and hardware capabilities, but according to the decision table [1] we should provide the correct dr_mode which is import for FIFO configuration and so on. Another problem that i see is that the USB behavior is influenced by compile settings in a unexpected way. With arm/configs/bcm2835_defconfig the driver is forced to host, but in a multiplatform config like arm64/configs/defconfig not. I would expect a more stable dr_mode. At the end the dwc2 can't reliable detect the dr_mode because it depends on the board design. Any concerns? Stefan [1] - https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/?id=5268ed9d2e3b52f703f3661eef14cecbb2b572d4 > > or something else? > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
