usb: dwc3: gadget: put link to U0 before Start Transfer

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
gadget 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@linux.intel.com>
This commit is contained in:
Felipe Balbi 2016-04-04 12:46:33 +03:00
parent 218ef7b647
commit c36d8e947a

View File

@ -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)
{
@ -248,6 +250,20 @@ int dwc3_send_gadget_ep_cmd(struct dwc3 *dwc, unsigned ep,
dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(0), reg);
}
if (cmd == DWC3_DEPCMD_STARTTRANSFER) {
int needs_wakeup;
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);
dwc3_writel(dwc->regs, DWC3_DEPCMDPAR1(ep), params->param1);
dwc3_writel(dwc->regs, DWC3_DEPCMDPAR2(ep), params->param2);