Assert reset before deassert in dwc2_reset; this patch solve issues when the DWC2 registers are already initialized with value incompatible with host mode.
Force a hardware reset of the IP reset all the DWC2 registers at default value, the host driver start with a clean state (Core Soft reset doen in dwc_otg_core_reset is not enought to reset all register).
The error can occurs in U-Boot when DWC2 device gadget driver force device mode (called by ums or dfu command, before to execute the usb start command).
Signed-off-by: Patrick Delaunay patrick.delaunay@st.com ---
Changes in v4: None Changes in v3: None Changes in v2: - add clk_disable_bulk in dwc2_usb_remove
drivers/usb/host/dwc2.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/usb/host/dwc2.c b/drivers/usb/host/dwc2.c index d56d0e61b5..f53913cde4 100644 --- a/drivers/usb/host/dwc2.c +++ b/drivers/usb/host/dwc2.c @@ -1151,6 +1151,8 @@ static int dwc2_reset(struct udevice *dev) return ret; }
+ /* force reset to clear all IP register */ + reset_assert_bulk(&priv->resets); ret = reset_deassert_bulk(&priv->resets); if (ret) { reset_release_bulk(&priv->resets);