usb: dwc3: Registering a role switch in the DRD code.

The Type-C drivers use USB role switch API to inform the
system about the negotiated data role, so registering a role
switch in the DRD code in order to support platforms with
USB Type-C connectors.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
CC: ShuFan Lee <shufan_lee@richtek.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Chunfeng Yun <chunfeng.yun@mediatek.com>
Cc: Yu Chen <chenyu56@huawei.com>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Jun Li <lijun.kernel@gmail.com>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Guillaume Gardet <Guillaume.Gardet@arm.com>
Cc: Jack Pham <jackp@codeaurora.org>
Cc: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Cc: linux-usb@vger.kernel.org
Cc: devicetree@vger.kernel.org
Suggested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Tested-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Yu Chen <chenyu56@huawei.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 3ecc69c..1e9513c 100644 (file)
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -25,6 +25,7 @@
 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.h>
 #include <linux/usb/otg.h>
+#include <linux/usb/role.h>
 #include <linux/ulpi/interface.h>
 
 #include <linux/phy/phy.h>
@@ -954,6 +955,7 @@ struct dwc3_scratchpad_array {
  * @hsphy_mode: UTMI phy mode, one of following:
  *             - USBPHY_INTERFACE_MODE_UTMI
  *             - USBPHY_INTERFACE_MODE_UTMIW
+ * @role_sw: usb_role_switch handle
  * @usb2_phy: pointer to USB2 PHY
  * @usb3_phy: pointer to USB3 PHY
  * @usb2_generic_phy: pointer to USB2 PHY
@@ -1089,6 +1091,7 @@ struct dwc3 {
        struct extcon_dev       *edev;
        struct notifier_block   edev_nb;
        enum usb_phy_interface  hsphy_mode;
+       struct usb_role_switch  *role_sw;
 
        u32                     fladj;
        u32                     irq_gadget;

diff --git a/drivers/usb/dwc3/drd.c b/drivers/usb/dwc3/drd.c
index c946d64..331c6e9 100644 (file)
--- a/drivers/usb/dwc3/drd.c
+++ b/drivers/usb/dwc3/drd.c
@@ -476,6 +476,73 @@ static struct extcon_dev *dwc3_get_extcon(struct dwc3 *dwc)
        return edev;
 }
 
+#if IS_ENABLED(CONFIG_USB_ROLE_SWITCH)
+#define ROLE_SWITCH 1
+static int dwc3_usb_role_switch_set(struct device *dev, enum usb_role role)
+{
+       struct dwc3 *dwc = dev_get_drvdata(dev);
+       u32 mode;
+
+       switch (role) {
+       case USB_ROLE_HOST:
+               mode = DWC3_GCTL_PRTCAP_HOST;
+               break;
+       case USB_ROLE_DEVICE:
+               mode = DWC3_GCTL_PRTCAP_DEVICE;
+               break;
+       default:
+               mode = DWC3_GCTL_PRTCAP_DEVICE;
+               break;
+       }
+
+       dwc3_set_mode(dwc, mode);
+       return 0;
+}
+
+static enum usb_role dwc3_usb_role_switch_get(struct device *dev)
+{
+       struct dwc3 *dwc = dev_get_drvdata(dev);
+       unsigned long flags;
+       enum usb_role role;
+
+       spin_lock_irqsave(&dwc->lock, flags);
+       switch (dwc->current_dr_role) {
+       case DWC3_GCTL_PRTCAP_HOST:
+               role = USB_ROLE_HOST;
+               break;
+       case DWC3_GCTL_PRTCAP_DEVICE:
+               role = USB_ROLE_DEVICE;
+               break;
+       case DWC3_GCTL_PRTCAP_OTG:
+               role = dwc->current_otg_role;
+               break;
+       default:
+               role = USB_ROLE_DEVICE;
+               break;
+       }
+       spin_unlock_irqrestore(&dwc->lock, flags);
+       return role;
+}
+
+static int dwc3_setup_role_switch(struct dwc3 *dwc)
+{
+       struct usb_role_switch_desc dwc3_role_switch = {NULL};
+
+       dwc3_role_switch.fwnode = dev_fwnode(dwc->dev);
+       dwc3_role_switch.set = dwc3_usb_role_switch_set;
+       dwc3_role_switch.get = dwc3_usb_role_switch_get;
+       dwc->role_sw = usb_role_switch_register(dwc->dev, &dwc3_role_switch);
+       if (IS_ERR(dwc->role_sw))
+               return PTR_ERR(dwc->role_sw);
+
+       dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_DEVICE);
+       return 0;
+}
+#else
+#define ROLE_SWITCH 0
+#define dwc3_setup_role_switch(x) 0
+#endif
+
 int dwc3_drd_init(struct dwc3 *dwc)
 {
        int ret, irq;
@@ -484,7 +551,12 @@ int dwc3_drd_init(struct dwc3 *dwc)
        if (IS_ERR(dwc->edev))
                return PTR_ERR(dwc->edev);
 
-       if (dwc->edev) {
+       if (ROLE_SWITCH &&
+           device_property_read_bool(dwc->dev, "usb-role-switch")) {
+               ret = dwc3_setup_role_switch(dwc);
+               if (ret < 0)
+                       return ret;
+       } else if (dwc->edev) {
                dwc->edev_nb.notifier_call = dwc3_drd_notifier;
                ret = extcon_register_notifier(dwc->edev, EXTCON_USB_HOST,
                                               &dwc->edev_nb);
@@ -531,6 +603,9 @@ void dwc3_drd_exit(struct dwc3 *dwc)
 {
        unsigned long flags;
 
+       if (dwc->role_sw)
+               usb_role_switch_unregister(dwc->role_sw);
+
        if (dwc->edev)
                extcon_unregister_notifier(dwc->edev, EXTCON_USB_HOST,
                                           &dwc->edev_nb);