On Wed, Feb 08, 2017 at 11:26:35AM +0100, Alexander Stein wrote: > This patch adds support for USB2 test mode (Test_J, Test_K, > Test_SE0_NAK and Test_Packet) per XHCI spec 4.19.6.
What does that mean "in English"? In other words, why do we want this? What does it provide for a user? Why do we care? > > Signed-off-by: "Wang, Yu" <yu.y.w...@intel.com> > Signed-off-by: "Li, Guanglei" <guangleix...@intel.com> > Signed-off-by: "Wu, Hao" <hao...@intel.com> > Signed-off-by: Alexander Stein <alexander.st...@systec-electronic.com> > --- > This patch was taken from > https://github.com/01org/ProductionKernelQuilts/blob/master/uefi/cht-m1stable/patches/0001-xhci-add-USB2-test-mode-support.patch > A major difference is that now a xhci_command has to be allocated manually. > > drivers/usb/host/xhci-hub.c | 63 > ++++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 62 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c > index 0ef1690..cd561f1 100644 > --- a/drivers/usb/host/xhci-hub.c > +++ b/drivers/usb/host/xhci-hub.c > @@ -879,13 +879,14 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, > u16 wValue, > int max_ports; > unsigned long flags; > u32 temp, status; > - int retval = 0; > + int i, retval = 0; > __le32 __iomem **port_array; > int slot_id; > struct xhci_bus_state *bus_state; > u16 link_state = 0; > u16 wake_mask = 0; > u16 timeout = 0; > + u16 selector = 0; > > max_ports = xhci_get_ports(hcd, &port_array); > bus_state = &xhci->bus_state[hcd_index(hcd)]; > @@ -959,6 +960,8 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, > u16 wValue, > link_state = (wIndex & 0xff00) >> 3; > if (wValue == USB_PORT_FEAT_REMOTE_WAKE_MASK) > wake_mask = wIndex & 0xff00; > + if (wValue == USB_PORT_FEAT_TEST) > + selector = (wIndex & 0xff00) >> 8; > /* The MSB of wIndex is the U1/U2 timeout */ > timeout = (wIndex & 0xff00) >> 8; > wIndex &= 0xff; > @@ -1134,6 +1137,64 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, > u16 wValue, > temp |= PORT_U2_TIMEOUT(timeout); > writel(temp, port_array[wIndex] + PORTPMSC); > break; > + case USB_PORT_FEAT_TEST: > + /* 4.19.6 Port Test Modes (USB2 Test Mode) */ > + if (hcd->speed != HCD_USB2) > + goto error; > + > + /* FIXME: Test_Force_Enable case to be implemented */ > + if (selector < TEST_J || selector > TEST_PACKET) > + goto error; > + > + /* Disable all Device Slots */ > + for (i = 0; i < MAX_HC_SLOTS; i++) { > + struct xhci_command *command; > + > + if (!xhci->dcbaa->dev_context_ptrs[i]) > + continue; > + command = xhci_alloc_command(xhci, false, > + false, GFP_ATOMIC); > + if (!command) > + return -ENOMEM; > + if (xhci_queue_slot_control(xhci, command, > + TRB_DISABLE_SLOT, i)) { > + xhci_err(xhci, > + "Disable slot[%d] fail!\n", i); > + goto error; > + } > + xhci_dbg(xhci, "Disable Slot[%d].\n", i); > + } > + > + /* Put all ports to the Disable state by clear PP */ > + xhci_dbg(xhci, "Disable all port (PP = 0)\n"); > + for (i = 0; i < max_ports; i++) { > + temp = readl(port_array[i]); > + temp &= ~PORT_POWER; > + writel(temp, port_array[i]); > + } > + > + /* Stop the controller */ > + xhci_dbg(xhci, "Stop controller\n"); > + temp = readl(&xhci->op_regs->command); > + temp &= ~CMD_RUN; > + writel(temp, &xhci->op_regs->command); > + > + if (xhci_handshake(&xhci->op_regs->status, > + STS_HALT, STS_HALT, XHCI_MAX_HALT_USEC)) { > + xhci_warn(xhci, "Stop controller timeout\n"); > + return -ETIMEDOUT; > + } > + > + /* Disable runtime PM for test mode */ > + pm_runtime_forbid(hcd->self.controller); > + > + /* Set PORTPMSC.PTC field for selected test mode */ > + xhci_dbg(xhci, "Enter Test Mode: %d\n", selector); > + temp = readl(port_array[wIndex] + PORTPMSC); > + temp |= selector << 28; > + writel(temp, port_array[wIndex] + PORTPMSC); > + > + break; What does this "test mode" do? Where does it report the information? Who can use it? thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html