Disable power_down by setting the parameter to DWC2_POWER_DOWN_PARAM_NONE. This fixes a problem on various Amlogic Meson SoCs where USB devices are only recognized when plugged in before booting Linux. A hot-plugged USB device was not detected even though the device got power (my USB thumb drive for example has an LED which lit up).
A similar fix was implemented for Rockchip SoCs in commit c216765d3a1def ("usb: dwc2: disable power_down on rockchip devices"). That commit suggests that a change in the dwc2 driver is the cause because the default value for the "hibernate" parameter (which then got renamed to "power_down" to support other modes) was changed in the v4.17 merge window with: commit 6d23ee9caa6790 ("Merge tag 'usb-for-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-testing").
Cc: stable@vger.kernel.org # 4.19 Suggested-by: Christian Hewitt christianshewitt@gmail.com Signed-off-by: Martin Blumenstingl martin.blumenstingl@googlemail.com --- drivers/usb/dwc2/params.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/usb/dwc2/params.c b/drivers/usb/dwc2/params.c index 7c1b6938f212..38c813b1d203 100644 --- a/drivers/usb/dwc2/params.c +++ b/drivers/usb/dwc2/params.c @@ -111,6 +111,7 @@ static void dwc2_set_amlogic_params(struct dwc2_hsotg *hsotg) p->phy_type = DWC2_PHY_TYPE_PARAM_UTMI; p->ahbcfg = GAHBCFG_HBSTLEN_INCR8 << GAHBCFG_HBSTLEN_SHIFT; + p->power_down = DWC2_POWER_DOWN_PARAM_NONE; }
static void dwc2_set_amcc_params(struct dwc2_hsotg *hsotg)