Kernel/USB: Detach devices from their driver when they are detached

Author: https://github.com/Hendiadyoin1
Commit: https://github.com/SerenityOS/serenity/commit/d168bfabc4
Pull-request: https://github.com/SerenityOS/serenity/pull/21090
Reviewed-by: https://github.com/ADKaster ✅
Reviewed-by: https://github.com/BertalanD
Reviewed-by: https://github.com/kleinesfilmroellchen ✅
Reviewed-by: https://github.com/supercomputer7 ✅

Kernel/Bus/USB/USBDevice.cpp

@@ -39,6 +39,7 @@ ErrorOr<NonnullLockRefPtr<Device>> Device::try_create(USBController const& contr
         if (result.is_error())
             continue;
         dbgln_if(USB_DEBUG, "Found driver {} for device {:04x}:{:04x}!", driver->name(), device->m_vendor_id, device->m_product_id);
+        device->set_driver(driver);
         break;
     }
 

Kernel/Bus/USB/USBDevice.h

@@ -10,6 +10,7 @@
 #include <AK/OwnPtr.h>
 #include <AK/Types.h>
 #include <AK/Vector.h>
+#include <Kernel/Bus/USB/Drivers/USBDriver.h>
 #include <Kernel/Bus/USB/USBConfiguration.h>
 #include <Kernel/Bus/USB/USBPipe.h>
 #include <Kernel/Locking/SpinlockProtected.h>
@@ -58,6 +59,14 @@ public:
 
     Vector<USBConfiguration> const& configurations() const { return m_configurations; }
 
+    void set_driver(Driver& driver) { m_driver = driver; }
+    void detach()
+    {
+        if (m_driver)
+            m_driver->detach(*this);
+        m_driver = nullptr;
+    }
+
     SpinlockProtected<RefPtr<SysFSUSBDeviceInformation>, LockRank::None>& sysfs_device_info_node(Badge<USB::Hub>) { return m_sysfs_device_info_node; }
 
 protected:
@@ -76,6 +85,8 @@ protected:
     NonnullLockRefPtr<USBController> m_controller;
     NonnullOwnPtr<ControlPipe> m_default_pipe; // Default communication pipe (endpoint0) used during enumeration
 
+    LockRefPtr<Driver> m_driver;
+
 private:
     IntrusiveListNode<Device, NonnullLockRefPtr<Device>> m_hub_child_node;
 

Kernel/Bus/USB/USBHub.cpp

@@ -295,6 +295,9 @@ void Hub::check_for_port_updates()
                         auto* hub_child = static_cast<Hub*>(device_to_remove.ptr());
                         hub_child->remove_children_from_sysfs();
                     }
+
+                    device_to_remove->detach();
+
                     m_children.remove(*device_to_remove);
                 } else {
                     dbgln_if(USB_DEBUG, "USB Hub: No child set up on port {}, ignoring detachment.", port_number);