usb: dwc2: Add a quirk to allow speed negotiation for Hisilicon Hi6220
The Hi6220's usb controller is limited in that it does not
support "Split Transactions", so it does not support communicating
with low-speed and full-speed devices behind a high-speed hub.
Thus it requires a quirk so that we can manually drop the usb
speed when low/full-speed are attached, and bump back to high
speed when they are removed.
Cc: Wei Xu <xuwei5@hisilicon.com>
Cc: Guodong Xu <guodong.xu@linaro.org>
Cc: Amit Pundir <amit.pundir@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: John Youn <johnyoun@synopsys.com>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Chen Yu <chenyu56@huawei.com>
Cc: Vardan Mikayelyan <mvardan@synopsys.com>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Signed-off-by: Chen Yu <chenyu56@huawei.com>
[jstultz: Reworked to simplify the patch, and made
commit log to be more specific about the issue]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
index 1f670c3..751f0dd 100644
--- a/drivers/usb/dwc2/hcd.c
+++ b/drivers/usb/dwc2/hcd.c
@@ -4868,6 +4868,61 @@ static void _dwc2_hcd_clear_tt_buffer_complete(struct usb_hcd *hcd,
spin_unlock_irqrestore(&hsotg->lock, flags);
}
+/*
+ * HPRT0_SPD_HIGH_SPEED: high speed
+ * HPRT0_SPD_FULL_SPEED: full speed
+ */
+static void dwc2_change_bus_speed(struct usb_hcd *hcd, int speed)
+{
+ struct dwc2_hsotg *hsotg = dwc2_hcd_to_hsotg(hcd);
+
+ if (hsotg->params.speed == speed)
+ return;
+
+ hsotg->params.speed = speed;
+ queue_work(hsotg->wq_otg, &hsotg->wf_otg);
+}
+
+static void dwc2_free_dev(struct usb_hcd *hcd, struct usb_device *udev)
+{
+ struct dwc2_hsotg *hsotg = dwc2_hcd_to_hsotg(hcd);
+
+ if (!hsotg->params.change_speed_quirk)
+ return;
+
+ /*
+ * On removal, set speed to default high-speed.
+ */
+ if (udev->parent && udev->parent->speed > USB_SPEED_UNKNOWN &&
+ udev->parent->speed < USB_SPEED_HIGH) {
+ dev_info(hsotg->dev, "Set speed to default high-speed\n");
+ dwc2_change_bus_speed(hcd, HPRT0_SPD_HIGH_SPEED);
+ }
+}
+
+static int dwc2_reset_device(struct usb_hcd *hcd, struct usb_device *udev)
+{
+ struct dwc2_hsotg *hsotg = dwc2_hcd_to_hsotg(hcd);
+
+ if (!hsotg->params.change_speed_quirk)
+ return 0;
+
+ if (udev->speed == USB_SPEED_HIGH) {
+ dev_info(hsotg->dev, "Set speed to high-speed\n");
+ dwc2_change_bus_speed(hcd, HPRT0_SPD_HIGH_SPEED);
+ } else if ((udev->speed == USB_SPEED_FULL ||
+ udev->speed == USB_SPEED_LOW)) {
+ /*
+ * Change speed setting to full-speed if there's
+ * a full-speed or low-speed device plugged in.
+ */
+ dev_info(hsotg->dev, "Set speed to full-speed\n");
+ dwc2_change_bus_speed(hcd, HPRT0_SPD_FULL_SPEED);
+ }
+
+ return 0;
+}
+
static struct hc_driver dwc2_hc_driver = {
.description = "dwc2_hsotg",
.product_desc = "DWC OTG Controller",
@@ -5023,6 +5078,11 @@ int dwc2_hcd_init(struct dwc2_hsotg *hsotg, int irq)
dev_warn(hsotg->dev, "can't set coherent DMA mask\n");
}
+ if (hsotg->params.change_speed_quirk) {
+ dwc2_hc_driver.free_dev = dwc2_free_dev;
+ dwc2_hc_driver.reset_device = dwc2_reset_device;
+ }
+
hcd = usb_create_hcd(&dwc2_hc_driver, hsotg->dev, dev_name(hsotg->dev));
if (!hcd)
goto error1;