From 8f1b9f05a9e2113a32ddd239af10308da198f7c8 Mon Sep 17 00:00:00 2001 From: Mark Kettenis Date: Tue, 19 Apr 2022 21:06:33 +0200 Subject: [PATCH] usb: xhci-dwc3: Support role switch default role When the device tree indicates support for role switching through the "usb-role-switch" property, take the "role-switch-default-mode" property into account when deciding which role to put the controller into. This makes USB devices work on Apple M1 systems where the device tree may include a "dr_mode" property that is set to "otg", but where we need to put the controller into "host" mode to see devices connected to the type-C ports. Signed-off-by: Mark Kettenis --- drivers/usb/common/common.c | 16 ++++++++++++++++ drivers/usb/host/xhci-dwc3.c | 6 ++++++ include/linux/usb/otg.h | 10 ++++++++++ 3 files changed, 32 insertions(+) diff --git a/drivers/usb/common/common.c b/drivers/usb/common/common.c index ee0c064f1f..cff86a51ae 100644 --- a/drivers/usb/common/common.c +++ b/drivers/usb/common/common.c @@ -40,6 +40,22 @@ enum usb_dr_mode usb_get_dr_mode(ofnode node) return USB_DR_MODE_UNKNOWN; } +enum usb_dr_mode usb_get_role_switch_default_mode(ofnode node) +{ + const char *dr_mode; + int i; + + dr_mode = ofnode_read_string(node, "role-switch-default-mode"); + if (!dr_mode) + return USB_DR_MODE_UNKNOWN; + + for (i = 0; i < ARRAY_SIZE(usb_dr_modes); i++) + if (!strcmp(dr_mode, usb_dr_modes[i])) + return i; + + return USB_DR_MODE_UNKNOWN; +} + static const char *const speed_names[] = { [USB_SPEED_UNKNOWN] = "UNKNOWN", [USB_SPEED_LOW] = "low-speed", diff --git a/drivers/usb/host/xhci-dwc3.c b/drivers/usb/host/xhci-dwc3.c index bec0d98081..1dbd65dfaa 100644 --- a/drivers/usb/host/xhci-dwc3.c +++ b/drivers/usb/host/xhci-dwc3.c @@ -209,6 +209,12 @@ static int xhci_dwc3_probe(struct udevice *dev) writel(reg, &dwc3_reg->g_usb2phycfg[0]); dr_mode = usb_get_dr_mode(dev_ofnode(dev)); + if (dr_mode == USB_DR_MODE_OTG && + dev_read_bool(dev, "usb-role-switch")) { + dr_mode = usb_get_role_switch_default_mode(dev_ofnode(dev)); + if (dr_mode == USB_DR_MODE_UNKNOWN) + dr_mode = USB_DR_MODE_OTG; + } if (dr_mode == USB_DR_MODE_UNKNOWN) /* by default set dual role mode to HOST */ dr_mode = USB_DR_MODE_HOST; diff --git a/include/linux/usb/otg.h b/include/linux/usb/otg.h index c19b916be9..5d0dac950e 100644 --- a/include/linux/usb/otg.h +++ b/include/linux/usb/otg.h @@ -27,6 +27,16 @@ enum usb_dr_mode { */ enum usb_dr_mode usb_get_dr_mode(ofnode node); +/** + * usb_get_dr_mode() - Get dual role mode for given device + * @node: ofnode of the given device + * + * The function gets phy interface string from property + * 'role-switch-defaulr-mode', and returns the correspondig enum + * usb_dr_mode + */ +enum usb_dr_mode usb_get_role_switch_default_mode(ofnode node); + /** * usb_get_maximum_speed() - Get maximum speed for given device * @node: ofnode of the given device -- 2.39.5