When host issues "fastboot reboot fastboot", it's expected that the board drops the USB connection before resetting.
On some boards, such as Khadas VIM3L and SEI610, this is not the case.
We observe the following error: $ fastboot reboot fastboot Rebooting into fastboot OKAY [ 0.004s] fastboot: error: Failed to boot into userspace fastboot; one or more components might be unbootable.
This does not happen when we use the RST button on the board. It can be reproduced in linux with: $ echo b > /proc/sysrq-trigger
In this case, we hit a undefined hardware behavior, where D+ and D- are in an unknown state. Therefore the host can't detect usb disconnection.
This series proposes 2 approaches for this problem: * generic fix, which ensures that usb_gadget_disconnect() is called when the board receives any "fastboot reboot" commands * platform specific reset implementation for g12a to ensure that the usb controller gets properly reset.
Changes in v2: * Transformed into a series to provide both generic and platform specific fix (Marek) * Simplified generic fix via g_dnl_trigger_detach() (Marek) * Link to v1: https://lore.kernel.org/r/20220721135955.360195-1-mkorpershoek@baylibre.com
Signed-off-by: Mattijs Korpershoek mkorpershoek@baylibre.com
--- Mattijs Korpershoek (2): usb: gadget: fastboot: detach usb on reboot commands mach-meson: g12a: reset usb controller in reset_misc()
arch/arm/mach-meson/board-g12a.c | 14 ++++++++++++++ cmd/fastboot.c | 2 +- configs/bananapi-m5_defconfig | 2 ++ configs/beelink-gsking-x_defconfig | 2 ++ configs/beelink-gtking_defconfig | 2 ++ configs/beelink-gtkingpro_defconfig | 2 ++ configs/khadas-vim3_android_ab_defconfig | 2 ++ configs/khadas-vim3_android_defconfig | 2 ++ configs/khadas-vim3_defconfig | 2 ++ configs/khadas-vim3l_android_ab_defconfig | 2 ++ configs/khadas-vim3l_android_defconfig | 2 ++ configs/khadas-vim3l_defconfig | 2 ++ configs/odroid-c4_defconfig | 2 ++ configs/odroid-hc4_defconfig | 2 ++ configs/odroid-n2_defconfig | 2 ++ configs/radxa-zero_defconfig | 2 ++ configs/u200_defconfig | 2 ++ drivers/usb/gadget/f_fastboot.c | 1 + 18 files changed, 46 insertions(+), 1 deletion(-) --- base-commit: 2d4591353452638132d711551fec3495b7644731 change-id: 20220728-reset-usb-controller-1b54be54b9d8
Best regards,