add mouse mode mouse compatability

separate 3 modes: media, WASD, mouse

g29-wheel/Makefile

@@ -0,0 +1,14 @@
+
+.PHONY: all clean install uninstall
+
+obj-m += g29_usb.o
+PWD := $(CURDIR)
+
+all:
+	$(MAKE) -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
+	mkdir -p build
+	-mv -f -- *.ko *.mod.c *.o .*.o *.mod modules.order .*.cmd *.symvers build/
+
+clean:
+	$(MAKE) -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean
+	rm -rf build

g29-wheel/g29_usb.c

@@ -0,0 +1,616 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Logitech G29 -> Media Keys (USB interface driver)
+ *
+ * Proof-of-concept Linux kernel module for low-level programming course.
+ *
+ * This driver:
+ *   - Binds to a Logitech G29 USB interface (VID/PID match)
+ *   - Receives 12-byte input reports via an interrupt-IN URB
+ *   - Parses the report into a normalized state (Stage A)
+ *   - Translates selected signals into media key events (Stage B)
+ *
+ * Stage A is designed to remain stable across different mapping policies.
+ * Stage B is designed to be replaced/extended by swapping mapping tables
+ * or adding per-signal handler functions.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+#include <linux/usb/input.h>
+#include <linux/input.h>
+#include <linux/timer.h>
+#include <linux/jiffies.h>
+#include <linux/hid.h>
+
+#include "g29_usb.h"
+
+MODULE_AUTHOR("LLP group 16");
+MODULE_DESCRIPTION("Logitech G29 USB driver");
+MODULE_LICENSE("GPL");
+
+enum g29_mode {
+	G29_MODE_MEDIA = 0,
+	G29_MODE_WASD = 1,
+	G29_MODE_MOUSE = 2,
+};
+
+static int mode = G29_MODE_MEDIA;
+module_param(mode, int, 0644);
+MODULE_PARM_DESC(mode, "Initial mode (0=MEDIA, 1=WASD, 2=MOUSE)");
+
+/* Steering curve exponent (100 = linear, 200 = squared, 150 = ^1.5)
+ * Higher values reduce sensitivity at low steering angles.
+ */
+static int steer_curve = 200;
+module_param(steer_curve, int, 0644);
+MODULE_PARM_DESC(steer_curve, "Steering sensitivity curve (100=linear, 200=squared, default=200)");
+
+static int steer_deadzone = 10;
+module_param(steer_deadzone, int, 0644);
+MODULE_PARM_DESC(steer_deadzone, "Steering deadzone radius from center (default=10)");
+
+static int gas_curve = 100;
+module_param(gas_curve, int, 0644);
+MODULE_PARM_DESC(gas_curve, "Gas pedal sensitivity curve (100=linear, 200=squared, default=200)");
+
+static int clutch_curve = 100;
+module_param(clutch_curve, int, 0644);
+MODULE_PARM_DESC(clutch_curve, "Clutch pedal sensitivity curve (100=linear, 200=squared, default=200)");
+
+#define NORMALIZATION_PRECISION 1000
+
+struct g29_keymap {
+	u32 mask;
+	unsigned short keycode;
+};
+
+static const struct g29_keymap media_mode_keymap[] = {
+	/* Red rotary = volume */
+	{ G29_BTN_RED_CW,  KEY_VOLUMEUP },
+	{ G29_BTN_RED_CCW, KEY_VOLUMEDOWN },
+
+	/* Return = play/pause */
+	{ G29_BTN_RETURN,  KEY_PLAYPAUSE },
+
+	/* Plus/Minus = next/prev */
+	{ G29_BTN_R1,    KEY_NEXTSONG },
+	{ G29_BTN_L1,   KEY_PREVIOUSSONG },
+};
+
+static const struct g29_keymap mouse_mode_keymap[] = {
+	{ G29_BTN_X,      BTN_LEFT },
+	{ G29_BTN_CIRCLE, BTN_RIGHT },
+	{ G29_BTN_TRIANGLE, BTN_MIDDLE },
+	{ G29_BTN_SQUARE, BTN_SIDE },
+};
+
+struct g29_dev {
+	char name[128];
+	char phys[64];
+
+	struct usb_device *udev;
+	struct input_dev *input;
+
+	struct urb *urb;
+	u8 *buf;
+	dma_addr_t buf_dma;
+	int maxp;
+	int interval;
+	int endpoint;
+
+	struct timer_list steer_timer;
+	struct timer_list mouse_timer;
+	u32 steer_phase_ms;
+
+	u32 phase_accumulator;
+	u32 gas_phase_accumulator;
+	u32 clutch_phase_accumulator;
+
+	enum g29_mode current_mode;
+	struct g29_state last;
+};
+
+
+
+static void g29_switch_mode(struct g29_dev *g29, enum g29_mode new_mode) {
+	if (g29->current_mode == new_mode)
+		return;
+
+	/* Stop timers when leaving modes */
+	if (g29->current_mode == G29_MODE_WASD) {
+		timer_delete_sync(&g29->steer_timer);
+	}
+	if (g29->current_mode == G29_MODE_MOUSE) {
+		timer_delete_sync(&g29->mouse_timer);
+	}
+
+	g29->current_mode = new_mode;
+	g29->phase_accumulator = 0;
+	g29->gas_phase_accumulator = 0;
+	g29->clutch_phase_accumulator = 0;
+
+	/* Start timers when entering modes */
+	if (new_mode == G29_MODE_WASD) {
+		mod_timer(&g29->steer_timer, jiffies + msecs_to_jiffies(2));
+	}
+	if (new_mode == G29_MODE_MOUSE) {
+		mod_timer(&g29->mouse_timer, jiffies + msecs_to_jiffies(10));
+	}
+
+	dev_info(&g29->udev->dev, "Switched to mode: %s\n",
+		 new_mode == G29_MODE_MEDIA ? "MEDIA" :
+		 new_mode == G29_MODE_WASD ? "WASD" : "MOUSE");
+}
+
+static int calc_adjusted_steering_distance(int distance) {
+	/* Apply non-linear steering curve:
+	 * adjusted = (distance / MAX)^(curve/100) * MAX
+	 *
+	 * For curve=200 (squared): 5% input -> 0.25% output, 50% -> 25%, 100% -> 100%
+	 * For curve=150 (^1.5):    5% input -> ~1.1% output, 50% -> ~35%, 100% -> 100%
+	 * For curve=100 (linear):  5% input -> 5% output (no change)
+	 *
+	 * Using integer math: adjusted = (distance^2 / MAX) for curve=200
+	 */
+	if (steer_curve == 100) {
+		return distance;
+	}
+	if (steer_curve == 200) {
+		return(distance * distance) / WHEEL_MAX_DIST;
+	}
+
+	/* Generic power curve using normalized values (0-1000 range for precision)
+	 * normalized = (distance * 1000) / WHEEL_MAX_DIST
+	 * Apply power approximation, then scale back
+	 */
+	int normalized = (distance * NORMALIZATION_PRECISION) / WHEEL_MAX_DIST;
+	int powered;
+
+	if (steer_curve == 150) {
+		/* Approximate ^1.5 with (x * sqrt(x)) */
+		int sqrt_norm = int_sqrt(normalized * NORMALIZATION_PRECISION);
+		powered = (normalized * sqrt_norm) / NORMALIZATION_PRECISION;
+	} else {
+		/* Fallback: squared for any other value > 100 */
+		powered = (normalized * normalized) / NORMALIZATION_PRECISION;
+	}
+
+	return (powered * WHEEL_MAX_DIST) / NORMALIZATION_PRECISION;
+}
+
+static int calc_adjusted_pedal_distance(int pedal_pressure, int curve) {
+	if (curve == 100) {
+		return pedal_pressure;
+	}
+	if (curve == 200) {
+		return (pedal_pressure * pedal_pressure) / G29_PEDAL_RELEASED;
+	}
+
+	int normalized = (pedal_pressure * NORMALIZATION_PRECISION) / G29_PEDAL_RELEASED;
+	int powered;
+
+	if (curve == 150) {
+		int sqrt_norm = int_sqrt(normalized * NORMALIZATION_PRECISION);
+		powered = (normalized * sqrt_norm) / NORMALIZATION_PRECISION;
+	} else {
+		powered = (normalized * normalized) / NORMALIZATION_PRECISION;
+	}
+
+	return (powered * G29_PEDAL_RELEASED) / NORMALIZATION_PRECISION;
+}
+
+static void mouse_mode_timer_fn(struct timer_list *t) {
+	struct g29_dev *g29 = timer_container_of(g29, t, mouse_timer);
+
+	const int rot = le16_to_cpu(g29->last.rot_le);
+	int gas_pressure = G29_PEDAL_RELEASED - g29->last.gas;
+	int clutch_pressure = G29_PEDAL_RELEASED - g29->last.clt;
+	
+	/* Calculate speed: positive for forward (gas), negative for backward (clutch) */
+	int speed = gas_pressure - clutch_pressure;
+	
+	/* Apply deadzone to steering */
+	int effective_rot = rot;
+	if (abs(rot - WHEEL_CENTER) <= steer_deadzone) {
+		effective_rot = WHEEL_CENTER;
+	}
+	
+	/* Calculate angle from wheel rotation
+	 * Map wheel rotation to angle: 
+	 * - Center (32768) = 0° (straight forward)
+	 * - Full left (0) = -180° (reverse)
+	 * - Full right (65535) = +180° (reverse)
+	 * We normalize to -1000 to +1000 representing -π to +π radians
+	 */
+	int angle_normalized = ((effective_rot - WHEEL_CENTER) * 1000) / WHEEL_CENTER;
+	
+	/* Clamp angle to prevent overflow */
+	if (angle_normalized > 1000) angle_normalized = 1000;
+	if (angle_normalized < -1000) angle_normalized = -1000;
+	
+	/* Calculate movement components using better trigonometric approximations:
+	 * dx = sin(angle) * speed
+	 * dy = cos(angle) * speed
+	 * 
+	 * sin(x) ≈ x - x³/6  (Taylor series)
+	 * cos(x) ≈ 1 - x²/2 + x⁴/24  (Taylor series)
+	 * 
+	 * For angle_normalized in [-1000, 1000] representing [-π, +π]:
+	 * This gives us full reverse when fully steered
+	 */
+	long angle_cubed = ((long)angle_normalized * angle_normalized * angle_normalized) / 1000000;
+	int sin_approx = (angle_normalized * 1000 - angle_cubed / 6) / 1000;
+	
+	long angle_squared = ((long)angle_normalized * angle_normalized) / 1000;
+	long angle_fourth = (angle_squared * angle_squared) / 1000;
+	int cos_approx = 1000 - angle_squared / 2 + angle_fourth / 24;
+	
+	int dx = (sin_approx * speed) / 1000;
+	int dy = -(cos_approx * speed) / 1000;  /* Negative because forward is -Y */
+	
+	/* Scale down the movement for reasonable mouse speed */
+	int scaled_dx = dx / 50;
+	int scaled_dy = dy / 50;
+	
+	/* Report mouse movement if there's any */
+	if (scaled_dx != 0 || scaled_dy != 0) {
+		input_report_rel(g29->input, REL_X, scaled_dx);
+		input_report_rel(g29->input, REL_Y, scaled_dy);
+		input_sync(g29->input);
+	}
+	
+	/* Reschedule timer if still in mouse mode */
+	if (g29->current_mode == G29_MODE_MOUSE)
+		mod_timer(&g29->mouse_timer, jiffies + msecs_to_jiffies(10));
+}
+static void wasd_mode_timer_fn(struct timer_list *t) {
+	struct g29_dev *g29 = timer_container_of(g29, t, steer_timer);
+
+	const int rot = le16_to_cpu(g29->last.rot_le);
+	
+	int effective_rot = rot;
+	int distance_from_center = abs(rot - WHEEL_CENTER);
+	if (distance_from_center <= steer_deadzone) {
+		effective_rot = WHEEL_CENTER;
+	}
+	
+	int distance_to_center = abs(effective_rot - WHEEL_CENTER);
+	int adjusted_distance = calc_adjusted_steering_distance(distance_to_center);
+
+	/* Phase accumulator approach:
+	 * Accumulate the adjusted distance on each tick.
+	 * When it exceeds the max distance, press the key and wrap.
+	 * This gives us a duty cycle of (adjusted_distance / WHEEL_MAX_DIST).
+	 *
+	 * Examples (with curve=200):
+	 *   5% steering  -> ~0.25% press rate
+	 *   50% steering -> 25% press rate
+	 *   100% steering -> 100% press rate (every tick)
+	 */
+	g29->phase_accumulator += adjusted_distance;
+
+	bool press_key;
+	if (g29->phase_accumulator >= WHEEL_MAX_DIST) {
+		g29->phase_accumulator -= WHEEL_MAX_DIST;
+		press_key = true;
+	} else {
+		press_key = false;
+	}
+
+	input_report_key(g29->input, KEY_A, press_key && (effective_rot < WHEEL_CENTER));
+	input_report_key(g29->input, KEY_D, press_key && (effective_rot >= WHEEL_CENTER));
+
+	/* Gas pedal (0xFF=up, 0x00=down) -> W key */
+	int gas_pressure = 0xFF - g29->last.gas;
+	int gas_adjusted = calc_adjusted_pedal_distance(gas_pressure, gas_curve);
+	g29->gas_phase_accumulator += gas_adjusted;
+
+	bool press_w = false;
+	if (g29->gas_phase_accumulator >= G29_PEDAL_RELEASED) {
+		g29->gas_phase_accumulator -= G29_PEDAL_RELEASED;
+		press_w = true;
+	}
+
+	/* Clutch pedal (0xFF=up, 0x00=down) -> S key */
+	int clutch_pressure = 0xFF - g29->last.clt;
+	int clutch_adjusted = calc_adjusted_pedal_distance(clutch_pressure, clutch_curve);
+	g29->clutch_phase_accumulator += clutch_adjusted;
+
+	bool press_s = false;
+	if (g29->clutch_phase_accumulator >= G29_PEDAL_RELEASED) {
+		g29->clutch_phase_accumulator -= G29_PEDAL_RELEASED;
+		press_s = true;
+	}
+
+	input_report_key(g29->input, KEY_W, press_w);
+	input_report_key(g29->input, KEY_S, press_s);
+
+	input_sync(g29->input);
+
+	if (g29->current_mode == G29_MODE_WASD)
+		mod_timer(&g29->steer_timer, jiffies + msecs_to_jiffies(2));
+}
+
+static void process_media_mode(struct g29_dev *g29, const struct g29_state *cur, const struct g29_state *prev) {
+	const u32 pressed = le32_to_cpu(cur->buttons_le & ~prev->buttons_le);
+	const u32 released = le32_to_cpu(~cur->buttons_le & prev->buttons_le);
+	for (int i = 0; i < ARRAY_SIZE(media_mode_keymap); i++) {
+		const struct g29_keymap *k = &media_mode_keymap[i];
+		if (pressed & k->mask) {
+			input_report_key(g29->input, k->keycode, 1);
+		}
+		if (released & k->mask) {
+			input_report_key(g29->input, k->keycode, 0);
+		}
+	}
+	input_sync(g29->input);
+}
+
+static void process_wasd_mode(struct g29_dev *g29, const struct g29_state *cur, const struct g29_state *prev) {
+	/* WASD mode is handled by the timer function (g29_steer_timer_fn) */
+	/* No additional processing needed here */
+}
+
+static void process_mouse_mode(struct g29_dev *g29, const struct g29_state *cur, const struct g29_state *prev) {
+	const u32 pressed = le32_to_cpu(cur->buttons_le & ~prev->buttons_le);
+	const u32 released = le32_to_cpu(~cur->buttons_le & prev->buttons_le);
+
+	for (int i = 0; i < ARRAY_SIZE(mouse_mode_keymap); i++) {
+		const struct g29_keymap *k = &mouse_mode_keymap[i];
+		if (pressed & k->mask) {
+			input_report_key(g29->input, k->keycode, 1);
+		}
+		if (released & k->mask) {
+			input_report_key(g29->input, k->keycode, 0);
+		}
+	}
+
+	if (pressed & G29_BTN_RED_CW) {
+		input_report_rel(g29->input, REL_WHEEL, 1);
+	}
+	if (pressed & G29_BTN_RED_CCW) {
+		input_report_rel(g29->input, REL_WHEEL, -1);
+	}
+	
+	input_sync(g29->input);
+}
+
+static void g29_check_mode_switch(struct g29_dev *g29, const struct g29_state *cur, const struct g29_state *prev) {
+	u32 pressed = le32_to_cpu(cur->buttons_le & ~prev->buttons_le);
+	
+	if (pressed & G29_BTN_SHARE) {
+		g29_switch_mode(g29, G29_MODE_MEDIA);
+	} else if (pressed & G29_BTN_OPTION) {
+		g29_switch_mode(g29, G29_MODE_WASD);
+	} else if (pressed & G29_BTN_PS3_LOGO) {
+		g29_switch_mode(g29, G29_MODE_MOUSE);
+	}
+}
+
+static void g29_process_report(struct g29_dev *g29, const u8 *data, unsigned int len) {
+	if (len < 12) return;
+
+	struct g29_state *cur = (void *) data;
+	
+	g29_check_mode_switch(g29, cur, &g29->last);
+	
+	switch (g29->current_mode) {
+		case G29_MODE_MEDIA:
+			process_media_mode(g29, cur, &g29->last);
+			break;
+		case G29_MODE_WASD:
+			process_wasd_mode(g29, cur, &g29->last);
+			break;
+		case G29_MODE_MOUSE:
+			process_mouse_mode(g29, cur, &g29->last);
+			break;
+	}
+
+	g29->last = *cur;
+}
+
+static void g29_urb_complete(struct urb *urb) {
+	struct g29_dev *g29 = urb->context;
+	int ret;
+
+	switch (urb->status) {
+	case 0:
+		break; /* success */
+	case -ECONNRESET:
+	case -ENOENT:
+	case -ESHUTDOWN:
+		return; /* cancelled/disconnected */
+	default:
+		goto resubmit; /* transient error */
+	}
+
+	g29_process_report(g29, g29->buf, urb->actual_length);
+
+resubmit:
+	ret = usb_submit_urb(urb, GFP_ATOMIC);
+	if (ret)
+		dev_err(&g29->udev->dev, "usb_submit_urb failed: %d\n", ret);
+}
+
+static int g29_input_open(struct input_dev *input) {
+	struct g29_dev *g29 = input_get_drvdata(input);
+
+	g29->urb->dev = g29->udev;
+	if (usb_submit_urb(g29->urb, GFP_KERNEL))
+		return -EIO;
+
+	g29_switch_mode(g29, mode);
+
+	return 0;
+}
+
+static void g29_input_close(struct input_dev *input) {
+	struct g29_dev *g29 = input_get_drvdata(input);
+	
+	if (g29->current_mode == G29_MODE_WASD)
+		timer_delete_sync(&g29->steer_timer);
+	if (g29->current_mode == G29_MODE_MOUSE)
+		timer_delete_sync(&g29->mouse_timer);
+	
+	usb_kill_urb(g29->urb);
+}
+
+static int g29_probe(struct usb_interface *intf, const struct usb_device_id *id) {
+	struct usb_device *udev = interface_to_usbdev(intf);
+	int ret;
+
+	/* Find an interrupt IN endpoint capable of carrying the 12-byte report. */
+	struct usb_endpoint_descriptor *ep = NULL;
+	const struct usb_host_interface *alts = intf->cur_altsetting;
+	for (int i = 0; i < alts->desc.bNumEndpoints; i++) {
+		struct usb_endpoint_descriptor *d = &alts->endpoint[i].desc;
+		if (!usb_endpoint_is_int_in(d))
+			continue;
+		if (usb_maxpacket(udev, usb_rcvintpipe(udev, d->bEndpointAddress)) >= 12) {
+			ep = d;
+			break;
+		}
+	}
+	if (!ep) return -ENODEV;
+
+	struct g29_dev *g29;
+	if ((g29 = kzalloc(sizeof(*g29), GFP_KERNEL)) == NULL) {
+		return -ENOMEM;
+	}
+
+	struct input_dev *input;
+	if ((input = input_allocate_device()) == NULL) {
+		ret = -ENOMEM;
+		goto err_free_g29;
+	}
+
+	g29->udev = udev;
+	g29->input = input;
+
+	g29->endpoint = usb_endpoint_num(ep);
+	g29->maxp = usb_endpoint_maxp(ep);
+	g29->interval = ep->bInterval;
+	memset(&g29->last, 0, sizeof(g29->last));
+	g29->current_mode = mode;  /* Initialize to module parameter */
+
+	timer_setup(&g29->steer_timer, wasd_mode_timer_fn, 0);
+	timer_setup(&g29->mouse_timer, mouse_mode_timer_fn, 0);
+
+	if ((g29->buf = usb_alloc_coherent(udev, g29->maxp, GFP_KERNEL, &g29->buf_dma)) == NULL) {
+		ret = -ENOMEM;
+		goto err_free_input;
+	}
+
+	if ((g29->urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL) {
+		ret = -ENOMEM;
+		goto err_free_buf;
+	}
+
+	if (udev->manufacturer)
+		strscpy(g29->name, udev->manufacturer, sizeof(g29->name));
+	if (udev->product) {
+		if (udev->manufacturer)
+			strlcat(g29->name, " ", sizeof(g29->name));
+		strlcat(g29->name, udev->product, sizeof(g29->name));
+	}
+	if (!strlen(g29->name))
+		snprintf(g29->name, sizeof(g29->name),
+			 "Logitech G29 USB %04x:%04x",
+			 le16_to_cpu(udev->descriptor.idVendor),
+			 le16_to_cpu(udev->descriptor.idProduct));
+
+	usb_make_path(udev, g29->phys, sizeof(g29->phys));
+	strlcat(g29->phys, "/input0", sizeof(g29->phys));
+
+	input->name = g29->name;
+	input->phys = g29->phys;
+	usb_to_input_id(udev, &input->id);
+	input->dev.parent = &intf->dev;
+
+	__set_bit(EV_KEY, input->evbit);
+	__set_bit(EV_REL, input->evbit);
+
+	/* Media mode keys */
+	input_set_capability(input, EV_KEY, KEY_VOLUMEUP);
+	input_set_capability(input, EV_KEY, KEY_VOLUMEDOWN);
+	input_set_capability(input, EV_KEY, KEY_PLAYPAUSE);
+	input_set_capability(input, EV_KEY, KEY_NEXTSONG);
+	input_set_capability(input, EV_KEY, KEY_PREVIOUSSONG);
+
+	/* WASD mode keys */
+	input_set_capability(input, EV_KEY, KEY_W);
+	input_set_capability(input, EV_KEY, KEY_A);
+	input_set_capability(input, EV_KEY, KEY_S);
+	input_set_capability(input, EV_KEY, KEY_D);
+
+	/* Mouse mode capabilities */
+	input_set_capability(input, EV_KEY, BTN_LEFT);
+	input_set_capability(input, EV_KEY, BTN_RIGHT);
+	input_set_capability(input, EV_KEY, BTN_MIDDLE);
+	input_set_capability(input, EV_REL, REL_X);
+	input_set_capability(input, EV_REL, REL_Y);
+	input_set_capability(input, EV_REL, REL_WHEEL);
+
+	input_set_drvdata(input, g29);
+	input->open = g29_input_open;
+	input->close = g29_input_close;
+
+	usb_fill_int_urb(g29->urb, udev, usb_rcvintpipe(udev, ep->bEndpointAddress),
+			 g29->buf, g29->maxp,
+			 g29_urb_complete, g29, ep->bInterval);
+	g29->urb->transfer_dma = g29->buf_dma;
+	g29->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+
+	if ((ret = input_register_device(input)) != 0) {
+		goto err_free_urb;
+	}
+
+	usb_set_intfdata(intf, g29);
+
+	dev_info(&intf->dev,
+		 "G29 media driver bound (ep=%02x interval=%u)\n",
+		 ep->bEndpointAddress, ep->bInterval);
+
+	return 0;
+
+err_free_urb:
+	usb_free_urb(g29->urb);
+err_free_buf:
+	usb_free_coherent(udev, g29->maxp, g29->buf, g29->buf_dma);
+err_free_input:
+	input_free_device(input);
+err_free_g29:
+	kfree(g29);
+	return ret;
+}
+
+static void g29_disconnect(struct usb_interface *intf) {
+	struct g29_dev *g29 = usb_get_intfdata(intf);
+	usb_set_intfdata(intf, NULL);
+	if (!g29) return;
+	usb_kill_urb(g29->urb);
+	input_unregister_device(g29->input);
+	usb_free_urb(g29->urb);
+	usb_free_coherent(interface_to_usbdev(intf), g29->maxp, g29->buf, g29->buf_dma);
+	kfree(g29);
+	dev_info(&intf->dev, "G29 driver disconnected\n");
+}
+
+static const struct usb_device_id g29_id_table[] = {
+	{ USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_G29) },
+	{ USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_G29_ALT) },
+	{ }
+};
+MODULE_DEVICE_TABLE(usb, g29_id_table);
+
+static struct usb_driver g29_driver = {
+	.name = "g29_usb",
+	.id_table = g29_id_table,
+	.probe = g29_probe,
+	.disconnect = g29_disconnect,
+};
+
+module_usb_driver(g29_driver);

g29-wheel/g29_usb.h

@@ -0,0 +1,76 @@
+/*
+ * Logitech G29 USB/HID Protocol Definitions
+ */
+
+#ifndef G29_USB_H
+#define G29_USB_H
+
+#include <linux/types.h>
+
+#define USB_VENDOR_ID_LOGITECH      0x046d
+#define USB_DEVICE_ID_LOGITECH_G29  0xc24f
+#define USB_DEVICE_ID_LOGITECH_G29_ALT 0xc260
+
+#define G29_BTN_X           0x00000010u
+#define G29_BTN_SQUARE      0x00000020u
+#define G29_BTN_CIRCLE      0x00000040u
+#define G29_BTN_TRIANGLE    0x00000080u
+#define G29_BTN_R1          0x00000100u
+#define G29_BTN_L1          0x00000200u
+#define G29_BTN_R2          0x00000400u
+#define G29_BTN_L2          0x00000800u
+#define G29_BTN_SHARE       0x00001000u
+#define G29_BTN_OPTION      0x00002000u
+#define G29_BTN_R3          0x00004000u
+#define G29_BTN_L3          0x00008000u
+#define G29_BTN_GEAR_1      0x00010000u
+#define G29_BTN_GEAR_2      0x00020000u
+#define G29_BTN_GEAR_3      0x00040000u
+#define G29_BTN_GEAR_4      0x00080000u
+#define G29_BTN_GEAR_5      0x00100000u
+#define G29_BTN_GEAR_6      0x00200000u
+#define G29_BTN_GEAR_REV    0x00400000u
+#define G29_BTN_PLUS        0x00800000u
+#define G29_BTN_MINUS       0x01000000u
+#define G29_BTN_RED_CW      0x02000000u
+#define G29_BTN_RED_CCW     0x04000000u
+#define G29_BTN_RETURN      0x08000000u
+#define G29_BTN_PS3_LOGO     0xF0000000u
+
+#define G29_DPAD_MASK       0x0000000Eu
+#define G29_DPAD_UP         0x00000000u
+#define G29_DPAD_RIGHT      0x00000002u
+#define G29_DPAD_DOWN       0x00000004u
+#define G29_DPAD_LEFT       0x00000006u
+#define G29_DPAD_NONE       0x00000008u
+
+#define G29_WHEEL_MIN_ROTATION           0x0000
+#define G29_WHEEL_MAX_ROTATION           0xFFFF
+
+#define G29_PEDAL_RELEASED      0xFF
+#define G29_PEDAL_PRESSED       0x00
+#define G29_PEDAL_THRESHOLD     0x80
+
+#define G29_GEARSHIFT_X_LEFT    0x30   /* Gears 1-2 */
+#define G29_GEARSHIFT_X_CENTER  0x80   /* Gears 3-4 */
+#define G29_GEARSHIFT_X_RIGHT   0xB0   /* Gears 5-6-R */
+#define G29_GEARSHIFT_Y_TOP     0xD0   /* Gears 1-3-5 */
+#define G29_GEARSHIFT_Y_BOTTOM  0x40   /* Gears 2-4-6-R */
+#define G29_GEARSHIFT_Z_NEUTRAL 0x9C   /* Neutral position */
+#define G29_GEARSHIFT_Z_PRESSED 0xDC   /* Pressed down */
+
+#define WHEEL_CENTER        32768
+#define WHEEL_MAX_DIST      32768
+
+struct g29_state {
+	u32 buttons_le;  /* Button bitmask (little-endian) */
+	u16 rot_le;      /* Wheel rotation (little-endian) */
+	u8 gas;          /* Gas pedal (0xFF=up, 0x00=down) */
+	u8 brk;          /* Brake pedal (0xFF=up, 0x00=down) */
+	u8 clt;          /* Clutch pedal (0xFF=up, 0x00=down) */
+	u8 gr_x;         /* Gearshift X-axis */
+	u8 gr_y;         /* Gearshift Y-axis */
+	u8 gr_z;         /* Gearshift Z-axis */
+} __packed;
+
+#endif

g29_media_usb/Makefile

@@ -1,28 +0,0 @@
-obj-m += g29_media_usb.o
-
-PWD := $(CURDIR)
-
-.PHONY: all clean install uninstall
-
-all:
-	$(MAKE) -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
-	mkdir -p build
-	mv -f *.ko build/ 2>/dev/null || true
-
-clean:
-	$(MAKE) -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean
-	rm -rf build
-
-install:
-	$(MAKE) -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules_install
-	depmod -a
-
-uninstall:
-	@modpath=$$(modinfo -n g29_media_usb 2>/dev/null); \
-	if [ -z "$$modpath" ]; then \
-		echo "Module g29_media_usb not found via modinfo (not installed?)"; \
-		exit 1; \
-	fi; \
-	echo "Removing $$modpath"; \
-	rm -f "$$modpath"; \
-	depmod -a

g29_media_usb/g29_media_usb.c

@@ -1,361 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Logitech G29 -> Media Keys (USB interface driver)
- *
- * Proof-of-concept Linux kernel module for low-level programming course.
- *
- * This driver:
- *   - Binds to a Logitech G29 USB interface (VID/PID match)
- *   - Receives 12-byte input reports via an interrupt-IN URB
- *   - Parses the report into a normalized state (Stage A)
- *   - Translates selected signals into media key events (Stage B)
- *
- * Stage A is designed to remain stable across different mapping policies.
- * Stage B is designed to be replaced/extended by swapping mapping tables
- * or adding per-signal handler functions.
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/slab.h>
-#include <linux/usb.h>
-#include <linux/usb/input.h>
-#include <linux/input.h>
-#include <asm/unaligned.h>
-
-MODULE_AUTHOR("LLP group 32");
-MODULE_DESCRIPTION("Logitech G29 -> Media keys (USB driver)");
-MODULE_LICENSE("GPL");
-
-#define USB_VENDOR_ID_LOGITECH      0x046d
-#define USB_DEVICE_ID_LOGITECH_G29  0xc24f
-#define USB_DEVICE_ID_LOGITECH_G29_ALT 0xc260
-
-#define G29_REPORT_LEN 12
-
-/*
- * Button masks
- */
-#define G29_BTN_PLUS        0x00800000u
-#define G29_BTN_MINUS       0x01000000u
-#define G29_BTN_RED_CW      0x02000000u
-#define G29_BTN_RED_CCW     0x04000000u
-#define G29_BTN_RETURN      0x08000000u
-#define G29_BTN_R1          0x00000100u
-#define G29_BTN_L1          0x00000200u
-
-enum g29_mode {
-	G29_MODE_MEDIA = 0,
-};
-
-static int mode = G29_MODE_MEDIA;
-module_param(mode, int, 0444);
-MODULE_PARM_DESC(mode, "Mapping mode (0=MEDIA)");
-
-struct g29_state {
-	u32 buttons;
-	u16 rot;
-	u8 gas;
-	u8 brk;
-	u8 clt;
-	u8 grx;
-	u8 gry;
-	u8 grz;
-};
-
-/*
- * Mapping table entry
- */
-struct g29_keymap_edge {
-	u32 mask;
-	unsigned short keycode;
-};
-
-static const struct g29_keymap_edge g29_media_edge_map[] = {
-	/* Red rotary = volume */
-	{ G29_BTN_RED_CW,  KEY_VOLUMEUP },
-	{ G29_BTN_RED_CCW, KEY_VOLUMEDOWN },
-
-	/* Return = play/pause */
-	{ G29_BTN_RETURN,  KEY_PLAYPAUSE },
-
-	/* Plus/Minus = next/prev */
-	{ G29_BTN_R1,    KEY_NEXTSONG },
-	{ G29_BTN_L1,   KEY_PREVIOUSSONG },
-};
-
-struct g29_dev {
-	char name[128];
-	char phys[64];
-
-	struct usb_device *udev;
-	struct input_dev *input;
-
-	struct urb *urb;
-	u8 *buf;
-	dma_addr_t buf_dma;
-
-	struct g29_state last;
-};
-
-/* Parsing */
-
-static bool g29_parse_report(struct g29_state *out, const u8 *data, int len)
-{
-	if (len < G29_REPORT_LEN)
-		return false;
-
-	/* bytes 0..3 buttons bitfield */
-	out->buttons = get_unaligned_le32(&data[0]);
-
-	/* bytes 4..5 rotation */
-	out->rot = get_unaligned_le16(&data[4]);
-
-	out->gas = data[6];
-	out->brk = data[7];
-	out->clt = data[8];
-	out->grx = data[9];
-	out->gry = data[10];
-	out->grz = data[11];
-
-	return true;
-}
-
-/* Mapping policy */
-
-static void g29_pulse_key(struct input_dev *input, unsigned short keycode)
-{
-	/* A pulse is a press+release within one report frame. */
-	input_report_key(input, keycode, 1);
-	input_report_key(input, keycode, 0);
-}
-
-static void g29_apply_media_mode(struct g29_dev *g29,
-				const struct g29_state *prev,
-				const struct g29_state *cur)
-{
-	u32 pressed = cur->buttons & ~prev->buttons;
-	size_t i;
-
-	for (i = 0; i < ARRAY_SIZE(g29_media_edge_map); i++) {
-		const struct g29_keymap_edge *e = &g29_media_edge_map[i];
-		if (pressed & e->mask)
-			g29_pulse_key(g29->input, e->keycode);
-	}
-
-	input_sync(g29->input);
-}
-
-static void g29_process_report(struct g29_dev *g29, const u8 *data, int len)
-{
-	struct g29_state cur;
-
-	if (!g29_parse_report(&cur, data, len))
-		return;
-
-	switch (mode) {
-	case G29_MODE_MEDIA:
-	default:
-		g29_apply_media_mode(g29, &g29->last, &cur);
-		break;
-	}
-
-	g29->last = cur;
-}
-
-/* URB plumbing */
-
-static void g29_urb_complete(struct urb *urb)
-{
-	struct g29_dev *g29 = urb->context;
-	int ret;
-
-	switch (urb->status) {
-	case 0:
-		break; /* success */
-	case -ECONNRESET:
-	case -ENOENT:
-	case -ESHUTDOWN:
-		return; /* cancelled/disconnected */
-	default:
-		goto resubmit; /* transient error */
-	}
-
-	g29_process_report(g29, g29->buf, urb->actual_length);
-
-resubmit:
-	ret = usb_submit_urb(urb, GFP_ATOMIC);
-	if (ret)
-		dev_err(&g29->udev->dev, "usb_submit_urb failed: %d\n", ret);
-}
-
-static int g29_input_open(struct input_dev *input)
-{
-	struct g29_dev *g29 = input_get_drvdata(input);
-
-	g29->urb->dev = g29->udev;
-	if (usb_submit_urb(g29->urb, GFP_KERNEL))
-		return -EIO;
-
-	return 0;
-}
-
-static void g29_input_close(struct input_dev *input)
-{
-	struct g29_dev *g29 = input_get_drvdata(input);
-
-	usb_kill_urb(g29->urb);
-}
-
-/* USB driver binding */
-
-static int g29_probe(struct usb_interface *intf, const struct usb_device_id *id)
-{
-	struct usb_device *udev = interface_to_usbdev(intf);
-	struct usb_host_interface *alts = intf->cur_altsetting;
-	struct usb_endpoint_descriptor *ep = NULL;
-	struct g29_dev *g29;
-	struct input_dev *input;
-	int i, pipe, maxp, error;
-
-	/* Find an interrupt IN endpoint capable of carrying the 12-byte report. */
-	for (i = 0; i < alts->desc.bNumEndpoints; i++) {
-		struct usb_endpoint_descriptor *cand = &alts->endpoint[i].desc;
-		if (!usb_endpoint_is_int_in(cand))
-			continue;
-		pipe = usb_rcvintpipe(udev, cand->bEndpointAddress);
-		maxp = usb_maxpacket(udev, pipe);
-		if (maxp >= G29_REPORT_LEN) {
-			ep = cand;
-			break;
-		}
-	}
-
-	if (!ep)
-		return -ENODEV;
-
-	g29 = kzalloc(sizeof(*g29), GFP_KERNEL);
-	if (!g29)
-		return -ENOMEM;
-
-	input = input_allocate_device();
-	if (!input) {
-		error = -ENOMEM;
-		goto err_free_g29;
-	}
-
-	g29->udev = udev;
-	g29->input = input;
-	memset(&g29->last, 0, sizeof(g29->last));
-
-	/* Allocate a fixed-size report buffer (12 bytes). */
-	g29->buf = usb_alloc_coherent(udev, G29_REPORT_LEN, GFP_KERNEL, &g29->buf_dma);
-	if (!g29->buf) {
-		error = -ENOMEM;
-		goto err_free_input;
-	}
-
-	g29->urb = usb_alloc_urb(0, GFP_KERNEL);
-	if (!g29->urb) {
-		error = -ENOMEM;
-		goto err_free_buf;
-	}
-
-	/* Build a friendly input device name. */
-	if (udev->manufacturer)
-		strscpy(g29->name, udev->manufacturer, sizeof(g29->name));
-	if (udev->product) {
-		if (udev->manufacturer)
-			strlcat(g29->name, " ", sizeof(g29->name));
-		strlcat(g29->name, udev->product, sizeof(g29->name));
-	}
-	if (!strlen(g29->name))
-		snprintf(g29->name, sizeof(g29->name),
-			 "Logitech G29 Media %04x:%04x",
-			 le16_to_cpu(udev->descriptor.idVendor),
-			 le16_to_cpu(udev->descriptor.idProduct));
-
-	usb_make_path(udev, g29->phys, sizeof(g29->phys));
-	strlcat(g29->phys, "/input0", sizeof(g29->phys));
-
-	input->name = g29->name;
-	input->phys = g29->phys;
-	usb_to_input_id(udev, &input->id);
-	input->dev.parent = &intf->dev;
-
-	__set_bit(EV_KEY, input->evbit);
-
-	/* Advertise only the keys we emit in media mode. */
-	input_set_capability(input, EV_KEY, KEY_VOLUMEUP);
-	input_set_capability(input, EV_KEY, KEY_VOLUMEDOWN);
-	input_set_capability(input, EV_KEY, KEY_PLAYPAUSE);
-	input_set_capability(input, EV_KEY, KEY_NEXTSONG);
-	input_set_capability(input, EV_KEY, KEY_PREVIOUSSONG);
-
-	input_set_drvdata(input, g29);
-	input->open = g29_input_open;
-	input->close = g29_input_close;
-
-	pipe = usb_rcvintpipe(udev, ep->bEndpointAddress);
-	usb_fill_int_urb(g29->urb, udev, pipe,
-			 g29->buf, G29_REPORT_LEN,
-			 g29_urb_complete, g29, ep->bInterval);
-	g29->urb->transfer_dma = g29->buf_dma;
-	g29->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
-
-	error = input_register_device(input);
-	if (error)
-		goto err_free_urb;
-
-	usb_set_intfdata(intf, g29);
-
-	dev_info(&intf->dev,
-		 "G29 media driver bound (ep=%02x interval=%u)\n",
-		 ep->bEndpointAddress, ep->bInterval);
-
-	return 0;
-
-err_free_urb:
-	usb_free_urb(g29->urb);
-err_free_buf:
-	usb_free_coherent(udev, G29_REPORT_LEN, g29->buf, g29->buf_dma);
-err_free_input:
-	input_free_device(input);
-err_free_g29:
-	kfree(g29);
-	return error;
-}
-
-static void g29_disconnect(struct usb_interface *intf)
-{
-	struct g29_dev *g29 = usb_get_intfdata(intf);
-
-	usb_set_intfdata(intf, NULL);
-	if (!g29)
-		return;
-
-	usb_kill_urb(g29->urb);
-	input_unregister_device(g29->input);
-	usb_free_urb(g29->urb);
-	usb_free_coherent(interface_to_usbdev(intf), G29_REPORT_LEN,
-			  g29->buf, g29->buf_dma);
-	kfree(g29);
-
-	dev_info(&intf->dev, "G29 media driver disconnected\n");
-}
-
-static const struct usb_device_id g29_id_table[] = {
-	{ USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_G29) },
-	{ USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_G29_ALT) },
-	{ }
-};
-MODULE_DEVICE_TABLE(usb, g29_id_table);
-
-static struct usb_driver g29_driver = {
-	.name = "g29_media_usb",
-	.probe = g29_probe,
-	.disconnect = g29_disconnect,
-	.id_table = g29_id_table,
-};
-
-module_usb_driver(g29_driver);

logitech-G29.md

@@ -45,7 +45,7 @@ Logitech G29 USB Protocol
     - `0x02000000` - Red rotation clockwise
     - `0x04000000` - Red rotation counterclockwise
     - `0x08000000` - Return
-    - `0xF0000000` - ?
+    - `0xF0000000` - Playstation 3 Logo Button (verify)
 - `Rot`: Wheel rotation (little-endian). `0x0000` (leftmost) - `0xFFFF` (rightmost).
 - `Gas`: Gas pedal. `0xFF` (up, default) - `0x00` (down).
 - `Brk`: Brake pedal. `0xFF` (up, default) - `0x00` (down).

wasd-emulator/Makefile

@@ -0,0 +1,25 @@
+
+.PHONY: all
+
+obj-m += wasd.o
+KVER := $(shell uname -r)
+KDIR ?= $(firstword $(wildcard /lib/modules/$(KVER)/build) $(wildcard /usr/lib/modules/$(KVER)/build))
+PWD := $(shell pwd)
+OUT := $(PWD)/out
+
+all:
+	@if [ -z "$(KDIR)" ]; then \
+		echo "ERROR: kernel build dir not found for $(KVER). Install kernel headers (e.g. linux-headers)"; \
+		exit 2; \
+	fi
+	mkdir -p $(OUT)
+	$(MAKE) -C $(KDIR) M=$(PWD) modules
+	-mv -f -- *.ko *.mod.c *.o .*.o *.mod modules.order .*.cmd *.symvers $(OUT)
+
+clean:
+	@if [ -z "$(KDIR)" ]; then \
+		echo "ERROR: kernel build dir not found for $(KVER)."; \
+		exit 2; \
+	fi
+	$(MAKE) -C $(KDIR) M=$(PWD) clean
+	rm -rf $(OUT) *.cmd *.order *.mod *.o

wasd-emulator/wasd.c

@@ -0,0 +1,223 @@
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/usb/ch9.h>
+#include <linux/usb/input.h>
+#include <linux/input.h>
+#include <linux/slab.h>
+
+#define DRV_NAME "usb_steeringwheel_wasd"
+
+struct wheel_evt {
+    uint32_t buttons_be;
+    uint16_t rot_be;
+    uint8_t gas;
+    uint8_t brk;
+    uint8_t clt;
+    uint8_t gr_x;
+    uint8_t gr_y;
+    uint8_t gr_z;
+};
+
+struct wheel {
+    struct usb_device *udev;
+    struct usb_interface *intf;
+    struct input_dev *input;
+
+    struct urb *irq_urb;
+    struct wheel_evt *irq_data;
+    dma_addr_t irq_dma;
+    int irq_len;
+    int irq_interval;
+    int irq_ep;
+
+    char phys[64];
+    atomic_t opened;
+};
+
+static int drv_open(struct input_dev *dev) {
+    struct wheel *w = input_get_drvdata(dev);
+    if (!w) return -ENODEV;
+    atomic_set(&w->opened, 1);
+    int ret;
+    if ((ret = usb_submit_urb(w->irq_urb, GFP_KERNEL))) {
+        atomic_set(&w->opened, 0);
+        return ret;
+    }
+    return 0;
+}
+
+static void drv_irq(struct urb *urb) {
+    // called every 2ms?
+    struct wheel *w = urb->context;
+    if (!w || !atomic_read(&w->opened))
+        return;
+
+    const int status = urb->status;
+    if (status) {
+        if (status == -ENOENT || status == -ECONNRESET || status == -ESHUTDOWN)
+            return;
+        dev_dbg(&w->intf->dev, "irq urb status %d\n", status);
+        goto resubmit;
+    }
+
+    const struct wheel_evt *data = w->irq_data;
+    const int rot = be16_to_cpu(data->buttons_be);
+    // TODO set keys according to ratio
+    input_report_key(w->input, KEY_W, data->gas <= 0x80);
+    input_report_key(w->input, KEY_S, data->brk <= 0x80);
+    input_report_key(w->input, KEY_A, rot <= 0x6000);
+    input_report_key(w->input, KEY_D, rot >= 0xA000);
+    input_sync(w->input);
+
+resubmit:
+    usb_submit_urb(w->irq_urb, GFP_ATOMIC);
+}
+
+static void drv_close(struct input_dev *dev) {
+    struct wheel *w = input_get_drvdata(dev);
+    if (!w) return;
+    atomic_set(&w->opened, 0);
+    usb_kill_urb(w->irq_urb);
+}
+
+static int drv_probe(struct usb_interface *intf, const struct usb_device_id *id) {
+    struct usb_device *udev = interface_to_usbdev(intf);
+    int ret;
+
+    // Logitech G29
+    //if (le16_to_cpu(udev->descriptor.idVendor) != 0x046d || le16_to_cpu(udev->descriptor.idProduct) != 0xc24f)
+    //    return -ENODEV;
+
+    struct usb_endpoint_descriptor *ep = NULL;
+    const struct usb_host_interface *alts = intf->cur_altsetting;
+    for (int i = 0; i < alts->desc.bNumEndpoints; i++) {
+        struct usb_endpoint_descriptor *d = &alts->endpoint[i].desc;
+        if (usb_endpoint_is_int_in(d)) {
+            ep = d;
+            break;
+        }
+    }
+    if (!ep) return -ENODEV;
+
+    struct wheel *w;
+    if ((w = kzalloc(sizeof(*w), GFP_KERNEL)) == NULL)
+        return -ENOMEM;
+
+    w->udev = usb_get_dev(udev);
+    w->intf = intf;
+    atomic_set(&w->opened, 0);
+
+    w->irq_ep = usb_endpoint_num(ep);
+    w->irq_len = usb_endpoint_maxp(ep);
+    w->irq_interval = ep->bInterval;
+
+    if ((w->irq_urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL) {
+        ret = -ENOMEM;
+        goto err_free;
+    }
+
+    if ((w->irq_data = usb_alloc_coherent(udev, w->irq_len, GFP_KERNEL, &w->irq_dma)) == NULL) {
+        ret = -ENOMEM;
+        goto err_free_urb;
+    }
+
+    if ((w->input = input_allocate_device()) == NULL) {
+        ret = -ENOMEM;
+        goto err_free_buf;
+    }
+
+    usb_make_path(udev, w->phys, sizeof(w->phys));
+    strlcat(w->phys, "/input0", sizeof(w->phys));
+
+    w->input->name = "USB Boot Mouse (example driver)";
+    w->input->phys = w->phys;
+    usb_to_input_id(udev, &w->input->id);
+    w->input->dev.parent = &intf->dev;
+
+    w->input->open = drv_open;
+    w->input->close = drv_close;
+
+    input_set_drvdata(w->input, w);
+
+    usb_fill_int_urb(
+        w->irq_urb,
+        udev,
+        usb_rcvintpipe(udev, ep->bEndpointAddress),
+        w->irq_data,
+        w->irq_len,
+        drv_irq,
+        w,
+        w->irq_interval);
+
+    w->irq_urb->transfer_dma = w->irq_dma;
+    w->irq_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+
+    usb_set_intfdata(intf, w);
+
+    if ((ret = input_register_device(w->input)) != 0)
+        goto err_clear_intfdata;
+
+    dev_info(&intf->dev,
+        "bound to %04x:%04x, int-in ep 0x%02x maxp %u interval %u\n",
+        le16_to_cpu(udev->descriptor.idVendor),
+        le16_to_cpu(udev->descriptor.idProduct),
+        ep->bEndpointAddress,
+        w->irq_len,
+        w->irq_interval);
+
+    return 0;
+
+err_clear_intfdata:
+    usb_set_intfdata(intf, NULL);
+    input_free_device(w->input);
+    w->input = NULL;
+err_free_buf:
+    usb_free_coherent(udev, w->irq_len, w->irq_data, w->irq_dma);
+err_free_urb:
+    usb_free_urb(w->irq_urb);
+err_free:
+    usb_put_dev(w->udev);
+    kfree(w);
+    return ret;
+}
+
+static void drv_disconnect(struct usb_interface *intf) {
+    struct wheel *w = usb_get_intfdata(intf);
+    usb_set_intfdata(intf, NULL);
+    if (!w) return;
+
+    if (w->input) {
+        input_unregister_device(w->input);
+        w->input = NULL;
+    }
+
+    usb_kill_urb(w->irq_urb);
+    usb_free_coherent(w->udev, w->irq_len, w->irq_data, w->irq_dma);
+    usb_free_urb(w->irq_urb);
+    usb_put_dev(w->udev);
+    kfree(w);
+
+    dev_info(&intf->dev, "disconnected\n");
+}
+
+static const struct usb_device_id drv_id_table[] = {
+    { USB_DEVICE_INTERFACE_NUMBER(0x046d, 0xc24f, 0) },
+    { USB_INTERFACE_INFO(3, 1, 1) },
+    {}
+};
+MODULE_DEVICE_TABLE(usb, drv_id_table);
+
+static struct usb_driver drv = {
+    .name = DRV_NAME,
+    .probe = drv_probe,
+    .disconnect = drv_disconnect,
+    .id_table = drv_id_table,
+};
+
+module_usb_driver(drv);
+
+MODULE_AUTHOR("Lorenz Stechauner");
+MODULE_DESCRIPTION("Steering wheel WASD emulator");
+MODULE_LICENSE("GPL");