From: Chen Yu <chenyu56@xxxxxxxxxx> 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@xxxxxxxxxxxxx> Cc: Guodong Xu <guodong.xu@xxxxxxxxxx> Cc: Amit Pundir <amit.pundir@xxxxxxxxxx> Cc: Rob Herring <robh+dt@xxxxxxxxxx> Cc: John Youn <johnyoun@xxxxxxxxxxxx> Cc: Douglas Anderson <dianders@xxxxxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: linux-usb@xxxxxxxxxxxxxxx Signed-off-by: Chen Yu <chenyu56@xxxxxxxxxx> [jstultz: Reworked to simplify the patch, and made commit log to be more specific about the issue] Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx> --- v2: * Fix build issue reported by kbuildbot * Rework to avoid using new dts entry suggested by RobH * Further tweaks from Chen Yu to try to address comments from John Youn * Further simplified logic --- drivers/usb/dwc2/core.h | 6 +++++ drivers/usb/dwc2/hcd.c | 61 +++++++++++++++++++++++++++++++++++++++++++++ drivers/usb/dwc2/platform.c | 1 + 3 files changed, 68 insertions(+) diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h index 2a21a04..baa4f64 100644 --- a/drivers/usb/dwc2/core.h +++ b/drivers/usb/dwc2/core.h @@ -417,6 +417,11 @@ enum dwc2_ep0_state { * needed. * 0 - No (default) * 1 - Yes + * @change_speed_quirk: Change speed configuration to DWC2_SPEED_PARAM_FULL + * while full&low speed device connect. And change speed + * back to DWC2_SPEED_PARAM_HIGH while device is gone. + * 0 - No (default) + * 1 - Yes * * The following parameters may be specified when starting the module. These * parameters define how the DWC_otg controller should be configured. A @@ -457,6 +462,7 @@ struct dwc2_core_params { int uframe_sched; int external_id_pin_ctl; int hibernation; + int change_speed_quirk; }; /** diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c index b374e60..85121e2 100644 --- a/drivers/usb/dwc2/hcd.c +++ b/drivers/usb/dwc2/hcd.c @@ -4868,6 +4868,62 @@ 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->core_params->speed == speed) + return; + + hsotg->core_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->core_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->core_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 +5079,11 @@ int dwc2_hcd_init(struct dwc2_hsotg *hsotg, int irq) dev_warn(hsotg->dev, "can't set coherent DMA mask\n"); } + if (hsotg->core_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; diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c index 8e1728b..17eb5fd 100644 --- a/drivers/usb/dwc2/platform.c +++ b/drivers/usb/dwc2/platform.c @@ -85,6 +85,7 @@ static const struct dwc2_core_params params_hi6220 = { .uframe_sched = 0, .external_id_pin_ctl = -1, .hibernation = -1, + .change_speed_quirk = 1, }; static const struct dwc2_core_params params_bcm2835 = { -- 2.7.4 -- 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