Synopsys Databook says we should move link to U0 before issuing a Start Transfer command. We could require the gadget driver to call usb_gadget_wakeup() however I feel that changing all gagdget drivers to keep track of Link State and conditionally call usb_gadget_wakeup() would be far too much work. For now we will handle this at the UDC level, but at some point composite.c should be one handling this. Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxxxx> --- drivers/usb/dwc3/gadget.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 552ebdf972b4..404573fcb3c9 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -221,6 +221,8 @@ int dwc3_send_gadget_generic_command(struct dwc3 *dwc, unsigned cmd, u32 param) } while (1); } +static int __dwc3_gadget_wakeup(struct dwc3 *dwc); + int dwc3_send_gadget_ep_cmd(struct dwc3 *dwc, unsigned ep, unsigned cmd, struct dwc3_gadget_ep_cmd_params *params) { @@ -242,12 +244,24 @@ int dwc3_send_gadget_ep_cmd(struct dwc3 *dwc, unsigned ep, * by the same section on Synopsys databook. */ if (cmd == DWC3_DEPCMD_STARTTRANSFER) { + int needs_wakeup; + reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0)); if (unlikely(reg & DWC3_GUSB2PHYCFG_SUSPHY)) { susphy = true; reg &= ~DWC3_GUSB2PHYCFG_SUSPHY; dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg); } + + needs_wakeup = (dwc->link_state == DWC3_LINK_STATE_U1 || + dwc->link_state == DWC3_LINK_STATE_U2 || + dwc->link_state == DWC3_LINK_STATE_U3); + + if (unlikely(needs_wakeup)) { + ret = __dwc3_gadget_wakeup(dwc); + dev_WARN_ONCE(dwc->dev, ret, "wakeup failed --> %d\n", + ret); + } } dwc3_writel(dwc->regs, DWC3_DEPCMDPAR0(ep), params->param0); -- 2.8.0.rc2 -- 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