There is no way to know whether the attached device is a hub or not in advance before the device's descriptor is fetched. But once we know it's a high speed hub, per the xHCI spec, we need to tell xHC it's a hub device by initializing hub-related fields in the input slot context.
Signed-off-by: Bin Meng bmeng.cn@gmail.com Reviewed-by: Simon Glass sjg@chromium.org
---
Changes in v3: None Changes in v2: - fix several nits in the commit message - add a comment for 666 in TT think time
drivers/usb/host/xhci.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+)
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 336613f..9b82ee5 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -1170,6 +1170,64 @@ static int xhci_alloc_device(struct udevice *dev, struct usb_device *udev) return _xhci_alloc_device(udev); }
+static int xhci_update_hub_device(struct udevice *dev, struct usb_device *udev) +{ + struct xhci_ctrl *ctrl = dev_get_priv(dev); + struct usb_hub_device *hub = dev_get_uclass_priv(udev->dev); + struct xhci_virt_device *virt_dev; + struct xhci_input_control_ctx *ctrl_ctx; + struct xhci_container_ctx *out_ctx; + struct xhci_container_ctx *in_ctx; + struct xhci_slot_ctx *slot_ctx; + int slot_id = udev->slot_id; + unsigned think_time; + + debug("%s: dev='%s', udev=%p\n", __func__, dev->name, udev); + + /* Ignore root hubs */ + if (usb_hub_is_root_hub(udev->dev)) + return 0; + + virt_dev = ctrl->devs[slot_id]; + BUG_ON(!virt_dev); + + out_ctx = virt_dev->out_ctx; + in_ctx = virt_dev->in_ctx; + + ctrl_ctx = xhci_get_input_control_ctx(in_ctx); + /* Initialize the input context control */ + ctrl_ctx->add_flags |= cpu_to_le32(SLOT_FLAG); + ctrl_ctx->drop_flags = 0; + + xhci_inval_cache((uintptr_t)out_ctx->bytes, out_ctx->size); + + /* slot context */ + xhci_slot_copy(ctrl, in_ctx, out_ctx); + slot_ctx = xhci_get_slot_ctx(ctrl, in_ctx); + + /* Update hub related fields */ + slot_ctx->dev_info |= cpu_to_le32(DEV_HUB); + if (hub->tt.multi && udev->speed == USB_SPEED_HIGH) + slot_ctx->dev_info |= cpu_to_le32(DEV_MTT); + slot_ctx->dev_info2 |= cpu_to_le32(XHCI_MAX_PORTS(udev->maxchild)); + /* + * Set TT think time - convert from ns to FS bit times. + * Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns + * + * 0 = 8 FS bit times, 1 = 16 FS bit times, + * 2 = 24 FS bit times, 3 = 32 FS bit times. + * + * This field shall be 0 if the device is not a high-spped hub. + */ + think_time = hub->tt.think_time; + if (think_time != 0) + think_time = (think_time / 666) - 1; + if (udev->speed == USB_SPEED_HIGH) + slot_ctx->tt_info |= cpu_to_le32(TT_THINK_TIME(think_time)); + + return xhci_configure_endpoints(udev, false); +} + int xhci_register(struct udevice *dev, struct xhci_hccr *hccr, struct xhci_hcor *hcor) { @@ -1222,6 +1280,7 @@ struct dm_usb_ops xhci_usb_ops = { .bulk = xhci_submit_bulk_msg, .interrupt = xhci_submit_int_msg, .alloc_device = xhci_alloc_device, + .update_hub_device = xhci_update_hub_device, };
#endif