diff --git a/Makefile b/Makefile
index 766deab..d163a1c 100644
--- a/Makefile
+++ b/Makefile
@@ -7,7 +7,7 @@
 AS = nasm
 ASFlAGS = -felf32
 EMU = qemu-system-x86_64
-EMUFLAGS = -m 1G -drive format=raw,file=$(IMAGE_FILE) -no-reboot -no-shutdown -monitor stdio -d int -D crashlog.log -s -d int
+EMUFLAGS = -m 1G -drive format=raw,file=$(IMAGE_FILE) -no-reboot -no-shutdown -monitor stdio -d int -D crashlog.log -s -d int -device qemu-xhci
 
 BUILD_FOLDER = build
 

diff --git a/Makefile b/Makefile
index 766deab..d163a1c 100644
--- a/Makefile
+++ b/Makefile
@@ -7,7 +7,7 @@
 AS = nasm
 ASFlAGS = -felf32
 EMU = qemu-system-x86_64
-EMUFLAGS = -m 1G -drive format=raw,file=$(IMAGE_FILE) -no-reboot -no-shutdown -monitor stdio -d int -D crashlog.log -s -d int
+EMUFLAGS = -m 1G -drive format=raw,file=$(IMAGE_FILE) -no-reboot -no-shutdown -monitor stdio -d int -D crashlog.log -s -d int -device qemu-xhci
 
 BUILD_FOLDER = build
 
diff --git a/src/userland/lspci/main.c b/src/userland/lspci/main.c
index 29ec790..33ac1cd 100644
--- a/src/userland/lspci/main.c
+++ b/src/userland/lspci/main.c
@@ -31,8 +31,7 @@
 uint32_t deviceCount = 0;
 
 ListElement *pciDevices = NULL;
-
-ListElement **getPciDevices() { return &pciDevices; }
+bool initialized = false;
 
 uint8_t pciConfigReadByte(uint32_t bus, uint32_t device, uint32_t function,
                           uint8_t offset) {
@@ -132,18 +131,36 @@
     }
 }
 
-bool initialized = false;
+int32_t getDeviceClass(uint32_t deviceId);
+
+void initializePci() {
+    createFunction("getDeviceClass", (void *)getDeviceClass);
+    if (!(getHeaderType(0, 0, 0) & 0x80)) {
+        checkBus(0);
+    } else {
+        for (uint8_t bus = 0; bus < 8; bus++) {
+            checkBus(bus);
+        }
+    }
+    deviceCount = listCount(pciDevices);
+    initialized = true;
+}
+
+int32_t getDeviceClass(uint32_t deviceId) {
+    if (!initialized) {
+        initializePci();
+    }
+    if (deviceId >= deviceCount) {
+        return 0;
+    }
+    PciDevice *device = listGet(pciDevices, deviceId);
+    return device->class << 16 | device->subclass << 8 |
+           device->programmingInterface;
+}
 
 int32_t main() {
     if (!initialized) {
-        if (!(getHeaderType(0, 0, 0) & 0x80)) {
-            checkBus(0);
-        } else {
-            for (uint8_t bus = 0; bus < 8; bus++) {
-                checkBus(bus);
-            }
-        }
-        initialized = true;
+        initializePci();
         return 0;
     }
     foreach (pciDevices, PciDevice *, device, {

diff --git a/Makefile b/Makefile
index 766deab..d163a1c 100644
--- a/Makefile
+++ b/Makefile
@@ -7,7 +7,7 @@
 AS = nasm
 ASFlAGS = -felf32
 EMU = qemu-system-x86_64
-EMUFLAGS = -m 1G -drive format=raw,file=$(IMAGE_FILE) -no-reboot -no-shutdown -monitor stdio -d int -D crashlog.log -s -d int
+EMUFLAGS = -m 1G -drive format=raw,file=$(IMAGE_FILE) -no-reboot -no-shutdown -monitor stdio -d int -D crashlog.log -s -d int -device qemu-xhci
 
 BUILD_FOLDER = build
 
diff --git a/src/userland/lspci/main.c b/src/userland/lspci/main.c
index 29ec790..33ac1cd 100644
--- a/src/userland/lspci/main.c
+++ b/src/userland/lspci/main.c
@@ -31,8 +31,7 @@
 uint32_t deviceCount = 0;
 
 ListElement *pciDevices = NULL;
-
-ListElement **getPciDevices() { return &pciDevices; }
+bool initialized = false;
 
 uint8_t pciConfigReadByte(uint32_t bus, uint32_t device, uint32_t function,
                           uint8_t offset) {
@@ -132,18 +131,36 @@
     }
 }
 
-bool initialized = false;
+int32_t getDeviceClass(uint32_t deviceId);
+
+void initializePci() {
+    createFunction("getDeviceClass", (void *)getDeviceClass);
+    if (!(getHeaderType(0, 0, 0) & 0x80)) {
+        checkBus(0);
+    } else {
+        for (uint8_t bus = 0; bus < 8; bus++) {
+            checkBus(bus);
+        }
+    }
+    deviceCount = listCount(pciDevices);
+    initialized = true;
+}
+
+int32_t getDeviceClass(uint32_t deviceId) {
+    if (!initialized) {
+        initializePci();
+    }
+    if (deviceId >= deviceCount) {
+        return 0;
+    }
+    PciDevice *device = listGet(pciDevices, deviceId);
+    return device->class << 16 | device->subclass << 8 |
+           device->programmingInterface;
+}
 
 int32_t main() {
     if (!initialized) {
-        if (!(getHeaderType(0, 0, 0) & 0x80)) {
-            checkBus(0);
-        } else {
-            for (uint8_t bus = 0; bus < 8; bus++) {
-                checkBus(bus);
-            }
-        }
-        initialized = true;
+        initializePci();
         return 0;
     }
     foreach (pciDevices, PciDevice *, device, {
diff --git a/src/userland/usb/Makefile b/src/userland/usb/Makefile
new file mode 100644
index 0000000..f3ac86a
--- /dev/null
+++ b/src/userland/usb/Makefile
@@ -0,0 +1,31 @@
+CC = i686-elf-gcc
+CCFLAGS = -m32 -mtune=generic -ffreestanding -nostdlib -c -I ../../include -I include -Wno-discarded-qualifiers -fms-extensions -Wno-shift-count-overflow -O0
+LD = i686-elf-ld
+LD_FLAGS = -z max-page-size=0x1000 -T ../link.ld
+AS = nasm
+ASFlAGS = -felf32
+
+BUILD_FOLDER = build
+
+SOURCE_FILES := $(shell find . -name *.c -or -name *.asm -or -name *.s)
+OBJS := $(SOURCE_FILES:%=$(BUILD_FOLDER)/%.o)
+
+NAME = usb
+
+../../../initrd/$(NAME): $(OBJS) ../../../build/hlib.o
+	@echo "linking user program $(NAME)"
+	@$(LD) $(LD_FLAGS) -o ../../../initrd/$(NAME) $(OBJS)
+
+$(BUILD_FOLDER)/%.asm.o: %.asm
+	@echo "asembling $<"
+	@mkdir -p $(dir $@)
+	@$(AS) $(ASFlAGS) $< -o $@
+
+$(BUILD_FOLDER)/%.c.o: %.c
+	@echo "compiling $<"
+	@mkdir -p $(dir $@)
+	@$(CC) $(CCFLAGS) -r $< -o $@
+
+clean:
+	@echo "clearing build folder"
+	@rm -r $(BUILD_FOLDER)

diff --git a/Makefile b/Makefile
index 766deab..d163a1c 100644
--- a/Makefile
+++ b/Makefile
@@ -7,7 +7,7 @@
 AS = nasm
 ASFlAGS = -felf32
 EMU = qemu-system-x86_64
-EMUFLAGS = -m 1G -drive format=raw,file=$(IMAGE_FILE) -no-reboot -no-shutdown -monitor stdio -d int -D crashlog.log -s -d int
+EMUFLAGS = -m 1G -drive format=raw,file=$(IMAGE_FILE) -no-reboot -no-shutdown -monitor stdio -d int -D crashlog.log -s -d int -device qemu-xhci
 
 BUILD_FOLDER = build
 
diff --git a/src/userland/lspci/main.c b/src/userland/lspci/main.c
index 29ec790..33ac1cd 100644
--- a/src/userland/lspci/main.c
+++ b/src/userland/lspci/main.c
@@ -31,8 +31,7 @@
 uint32_t deviceCount = 0;
 
 ListElement *pciDevices = NULL;
-
-ListElement **getPciDevices() { return &pciDevices; }
+bool initialized = false;
 
 uint8_t pciConfigReadByte(uint32_t bus, uint32_t device, uint32_t function,
                           uint8_t offset) {
@@ -132,18 +131,36 @@
     }
 }
 
-bool initialized = false;
+int32_t getDeviceClass(uint32_t deviceId);
+
+void initializePci() {
+    createFunction("getDeviceClass", (void *)getDeviceClass);
+    if (!(getHeaderType(0, 0, 0) & 0x80)) {
+        checkBus(0);
+    } else {
+        for (uint8_t bus = 0; bus < 8; bus++) {
+            checkBus(bus);
+        }
+    }
+    deviceCount = listCount(pciDevices);
+    initialized = true;
+}
+
+int32_t getDeviceClass(uint32_t deviceId) {
+    if (!initialized) {
+        initializePci();
+    }
+    if (deviceId >= deviceCount) {
+        return 0;
+    }
+    PciDevice *device = listGet(pciDevices, deviceId);
+    return device->class << 16 | device->subclass << 8 |
+           device->programmingInterface;
+}
 
 int32_t main() {
     if (!initialized) {
-        if (!(getHeaderType(0, 0, 0) & 0x80)) {
-            checkBus(0);
-        } else {
-            for (uint8_t bus = 0; bus < 8; bus++) {
-                checkBus(bus);
-            }
-        }
-        initialized = true;
+        initializePci();
         return 0;
     }
     foreach (pciDevices, PciDevice *, device, {
diff --git a/src/userland/usb/Makefile b/src/userland/usb/Makefile
new file mode 100644
index 0000000..f3ac86a
--- /dev/null
+++ b/src/userland/usb/Makefile
@@ -0,0 +1,31 @@
+CC = i686-elf-gcc
+CCFLAGS = -m32 -mtune=generic -ffreestanding -nostdlib -c -I ../../include -I include -Wno-discarded-qualifiers -fms-extensions -Wno-shift-count-overflow -O0
+LD = i686-elf-ld
+LD_FLAGS = -z max-page-size=0x1000 -T ../link.ld
+AS = nasm
+ASFlAGS = -felf32
+
+BUILD_FOLDER = build
+
+SOURCE_FILES := $(shell find . -name *.c -or -name *.asm -or -name *.s)
+OBJS := $(SOURCE_FILES:%=$(BUILD_FOLDER)/%.o)
+
+NAME = usb
+
+../../../initrd/$(NAME): $(OBJS) ../../../build/hlib.o
+	@echo "linking user program $(NAME)"
+	@$(LD) $(LD_FLAGS) -o ../../../initrd/$(NAME) $(OBJS)
+
+$(BUILD_FOLDER)/%.asm.o: %.asm
+	@echo "asembling $<"
+	@mkdir -p $(dir $@)
+	@$(AS) $(ASFlAGS) $< -o $@
+
+$(BUILD_FOLDER)/%.c.o: %.c
+	@echo "compiling $<"
+	@mkdir -p $(dir $@)
+	@$(CC) $(CCFLAGS) -r $< -o $@
+
+clean:
+	@echo "clearing build folder"
+	@rm -r $(BUILD_FOLDER)
diff --git a/src/userland/usb/main.c b/src/userland/usb/main.c
new file mode 100644
index 0000000..a6457bd
--- /dev/null
+++ b/src/userland/usb/main.c
@@ -0,0 +1,14 @@
+#define ALLOC_MAIN
+#include <hlib.h>
+
+#include "usb.h"
+
+int32_t main() {
+    uint32_t pciService = getService("lspci");
+    uint32_t function = getFunction(pciService, "getDeviceClass");
+    uint32_t i = 0, class = 0;
+    while ((class = request(pciService, function, i, 0))) {
+        printf("device %i has class 0x%x\n", i, class);
+        i++;
+    }
+}

diff --git a/Makefile b/Makefile
index 766deab..d163a1c 100644
--- a/Makefile
+++ b/Makefile
@@ -7,7 +7,7 @@
 AS = nasm
 ASFlAGS = -felf32
 EMU = qemu-system-x86_64
-EMUFLAGS = -m 1G -drive format=raw,file=$(IMAGE_FILE) -no-reboot -no-shutdown -monitor stdio -d int -D crashlog.log -s -d int
+EMUFLAGS = -m 1G -drive format=raw,file=$(IMAGE_FILE) -no-reboot -no-shutdown -monitor stdio -d int -D crashlog.log -s -d int -device qemu-xhci
 
 BUILD_FOLDER = build
 
diff --git a/src/userland/lspci/main.c b/src/userland/lspci/main.c
index 29ec790..33ac1cd 100644
--- a/src/userland/lspci/main.c
+++ b/src/userland/lspci/main.c
@@ -31,8 +31,7 @@
 uint32_t deviceCount = 0;
 
 ListElement *pciDevices = NULL;
-
-ListElement **getPciDevices() { return &pciDevices; }
+bool initialized = false;
 
 uint8_t pciConfigReadByte(uint32_t bus, uint32_t device, uint32_t function,
                           uint8_t offset) {
@@ -132,18 +131,36 @@
     }
 }
 
-bool initialized = false;
+int32_t getDeviceClass(uint32_t deviceId);
+
+void initializePci() {
+    createFunction("getDeviceClass", (void *)getDeviceClass);
+    if (!(getHeaderType(0, 0, 0) & 0x80)) {
+        checkBus(0);
+    } else {
+        for (uint8_t bus = 0; bus < 8; bus++) {
+            checkBus(bus);
+        }
+    }
+    deviceCount = listCount(pciDevices);
+    initialized = true;
+}
+
+int32_t getDeviceClass(uint32_t deviceId) {
+    if (!initialized) {
+        initializePci();
+    }
+    if (deviceId >= deviceCount) {
+        return 0;
+    }
+    PciDevice *device = listGet(pciDevices, deviceId);
+    return device->class << 16 | device->subclass << 8 |
+           device->programmingInterface;
+}
 
 int32_t main() {
     if (!initialized) {
-        if (!(getHeaderType(0, 0, 0) & 0x80)) {
-            checkBus(0);
-        } else {
-            for (uint8_t bus = 0; bus < 8; bus++) {
-                checkBus(bus);
-            }
-        }
-        initialized = true;
+        initializePci();
         return 0;
     }
     foreach (pciDevices, PciDevice *, device, {
diff --git a/src/userland/usb/Makefile b/src/userland/usb/Makefile
new file mode 100644
index 0000000..f3ac86a
--- /dev/null
+++ b/src/userland/usb/Makefile
@@ -0,0 +1,31 @@
+CC = i686-elf-gcc
+CCFLAGS = -m32 -mtune=generic -ffreestanding -nostdlib -c -I ../../include -I include -Wno-discarded-qualifiers -fms-extensions -Wno-shift-count-overflow -O0
+LD = i686-elf-ld
+LD_FLAGS = -z max-page-size=0x1000 -T ../link.ld
+AS = nasm
+ASFlAGS = -felf32
+
+BUILD_FOLDER = build
+
+SOURCE_FILES := $(shell find . -name *.c -or -name *.asm -or -name *.s)
+OBJS := $(SOURCE_FILES:%=$(BUILD_FOLDER)/%.o)
+
+NAME = usb
+
+../../../initrd/$(NAME): $(OBJS) ../../../build/hlib.o
+	@echo "linking user program $(NAME)"
+	@$(LD) $(LD_FLAGS) -o ../../../initrd/$(NAME) $(OBJS)
+
+$(BUILD_FOLDER)/%.asm.o: %.asm
+	@echo "asembling $<"
+	@mkdir -p $(dir $@)
+	@$(AS) $(ASFlAGS) $< -o $@
+
+$(BUILD_FOLDER)/%.c.o: %.c
+	@echo "compiling $<"
+	@mkdir -p $(dir $@)
+	@$(CC) $(CCFLAGS) -r $< -o $@
+
+clean:
+	@echo "clearing build folder"
+	@rm -r $(BUILD_FOLDER)
diff --git a/src/userland/usb/main.c b/src/userland/usb/main.c
new file mode 100644
index 0000000..a6457bd
--- /dev/null
+++ b/src/userland/usb/main.c
@@ -0,0 +1,14 @@
+#define ALLOC_MAIN
+#include <hlib.h>
+
+#include "usb.h"
+
+int32_t main() {
+    uint32_t pciService = getService("lspci");
+    uint32_t function = getFunction(pciService, "getDeviceClass");
+    uint32_t i = 0, class = 0;
+    while ((class = request(pciService, function, i, 0))) {
+        printf("device %i has class 0x%x\n", i, class);
+        i++;
+    }
+}
diff --git a/src/userland/usb/usb.h b/src/userland/usb/usb.h
new file mode 100644
index 0000000..947aa51
--- /dev/null
+++ b/src/userland/usb/usb.h
@@ -0,0 +1,6 @@
+#ifndef USB_H
+#define USB_H
+
+#include <hlib.h>
+
+#endif