hid-thrustmaster.c

  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * When connected to the machine, the Thrustmaster wheels appear as
  4 * a «generic» hid gamepad called "Thrustmaster FFB Wheel".
  5 *
  6 * When in this mode not every functionality of the wheel, like the force feedback,
  7 * are available. To enable all functionalities of a Thrustmaster wheel we have to send
  8 * to it a specific USB CONTROL request with a code different for each wheel.
  9 *
 10 * This driver tries to understand which model of Thrustmaster wheel the generic
 11 * "Thrustmaster FFB Wheel" really is and then sends the appropriate control code.
 12 *
 13 * Copyright (c) 2020-2021 Dario Pagani <dario.pagani.146+linuxk@gmail.com>
 14 * Copyright (c) 2020-2021 Kim Kuparinen <kimi.h.kuparinen@gmail.com>
 15 */
 16#include <linux/hid.h>
 17#include <linux/usb.h>
 18#include <linux/input.h>
 19#include <linux/slab.h>
 20#include <linux/module.h>
 21
 22/*
 23 * These interrupts are used to prevent a nasty crash when initializing the
 24 * T300RS. Used in thrustmaster_interrupts().
 25 */
 26static const u8 setup_0[] = { 0x42, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
 27static const u8 setup_1[] = { 0x0a, 0x04, 0x90, 0x03, 0x00, 0x00, 0x00, 0x00 };
 28static const u8 setup_2[] = { 0x0a, 0x04, 0x00, 0x0c, 0x00, 0x00, 0x00, 0x00 };
 29static const u8 setup_3[] = { 0x0a, 0x04, 0x12, 0x10, 0x00, 0x00, 0x00, 0x00 };
 30static const u8 setup_4[] = { 0x0a, 0x04, 0x00, 0x06, 0x00, 0x00, 0x00, 0x00 };
 31static const u8 *const setup_arr[] = { setup_0, setup_1, setup_2, setup_3, setup_4 };
 32static const unsigned int setup_arr_sizes[] = {
 33	ARRAY_SIZE(setup_0),
 34	ARRAY_SIZE(setup_1),
 35	ARRAY_SIZE(setup_2),
 36	ARRAY_SIZE(setup_3),
 37	ARRAY_SIZE(setup_4)
 38};
 39/*
 40 * This struct contains for each type of
 41 * Thrustmaster wheel
 42 *
 43 * Note: The values are stored in the CPU
 44 * endianness, the USB protocols always use
 45 * little endian; the macro cpu_to_le[BIT]()
 46 * must be used when preparing USB packets
 47 * and vice-versa
 48 */
 49struct tm_wheel_info {
 50	uint16_t wheel_type;
 51
 52	/*
 53	 * See when the USB control out packet is prepared...
 54	 * @TODO The TMX seems to require multiple control codes to switch.
 55	 */
 56	uint16_t switch_value;
 57
 58	char const *const wheel_name;
 59};
 60
 61/*
 62 * Known wheels.
 63 * Note: TMX does not work as it requires 2 control packets
 64 */
 65static const struct tm_wheel_info tm_wheels_infos[] = {
 66	{0x0306, 0x0006, "Thrustmaster T150RS"},
 67	{0x0200, 0x0005, "Thrustmaster T300RS (Missing Attachment)"},
 68	{0x0206, 0x0005, "Thrustmaster T300RS"},
 69	{0x0209, 0x0005, "Thrustmaster T300RS (Open Wheel Attachment)"},
 70	{0x020a, 0x0005, "Thrustmaster T300RS (Sparco R383 Mod)"},
 71	{0x0204, 0x0005, "Thrustmaster T300 Ferrari Alcantara Edition"},
 72	{0x0002, 0x0002, "Thrustmaster T500RS"}
 73	//{0x0407, 0x0001, "Thrustmaster TMX"}
 74};
 75
 76static const uint8_t tm_wheels_infos_length = 7;
 77
 78/*
 79 * This structs contains (in little endian) the response data
 80 * of the wheel to the request 73
 81 *
 82 * A sufficient research to understand what each field does is not
 83 * beign conducted yet. The position and meaning of fields are a
 84 * just a very optimistic guess based on instinct....
 85 */
 86struct __packed tm_wheel_response
 87{
 88	/*
 89	 * Seems to be the type of packet
 90	 * - 0x0049 if is data.a (15 bytes)
 91	 * - 0x0047 if is data.b (7 bytes)
 92	 */
 93	uint16_t type;
 94
 95	union {
 96		struct __packed {
 97			uint16_t field0;
 98			uint16_t field1;
 99			/*
100			 * Seems to be the model code of the wheel
101			 * Read table thrustmaster_wheels to values
102			 */
103			uint16_t model;
104
105			uint16_t field2;
106			uint16_t field3;
107			uint16_t field4;
108			uint16_t field5;
109		} a;
110		struct __packed {
111			uint16_t field0;
112			uint16_t field1;
113			uint16_t model;
114		} b;
115	} data;
116};
117
118struct tm_wheel {
119	struct usb_device *usb_dev;
120	struct urb *urb;
121
122	struct usb_ctrlrequest *model_request;
123	struct tm_wheel_response *response;
124
125	struct usb_ctrlrequest *change_request;
126};
127
128/* The control packet to send to wheel */
129static const struct usb_ctrlrequest model_request = {
130	.bRequestType = 0xc1,
131	.bRequest = 73,
132	.wValue = 0,
133	.wIndex = 0,
134	.wLength = cpu_to_le16(0x0010)
135};
136
137static const struct usb_ctrlrequest change_request = {
138	.bRequestType = 0x41,
139	.bRequest = 83,
140	.wValue = 0, // Will be filled by the driver
141	.wIndex = 0,
142	.wLength = 0
143};
144
145/*
146 * On some setups initializing the T300RS crashes the kernel,
147 * these interrupts fix that particular issue. So far they haven't caused any
148 * adverse effects in other wheels.
149 */
150static void thrustmaster_interrupts(struct hid_device *hdev)
151{
152	int ret, trans, i, b_ep;
153	u8 *send_buf = kmalloc(256, GFP_KERNEL);
154	struct usb_host_endpoint *ep;
155	struct device *dev = &hdev->dev;
156	struct usb_interface *usbif = to_usb_interface(dev->parent);
157	struct usb_device *usbdev = interface_to_usbdev(usbif);
158
159	if (!send_buf) {
160		hid_err(hdev, "failed allocating send buffer\n");
161		return;
162	}
163
164	if (usbif->cur_altsetting->desc.bNumEndpoints < 2) {
165		kfree(send_buf);
166		hid_err(hdev, "Wrong number of endpoints?\n");
167		return;
168	}
169
170	ep = &usbif->cur_altsetting->endpoint[1];
171	b_ep = ep->desc.bEndpointAddress;
172
173	/* Are the expected endpoints present? */
174	u8 ep_addr[2] = {b_ep, 0};
175
176	if (!usb_check_int_endpoints(usbif, ep_addr)) {
177		kfree(send_buf);
178		hid_err(hdev, "Unexpected non-int endpoint\n");
179		return;
180	}
181
182	for (i = 0; i < ARRAY_SIZE(setup_arr); ++i) {
183		memcpy(send_buf, setup_arr[i], setup_arr_sizes[i]);
184
185		ret = usb_interrupt_msg(usbdev,
186			usb_sndintpipe(usbdev, b_ep),
187			send_buf,
188			setup_arr_sizes[i],
189			&trans,
190			USB_CTRL_SET_TIMEOUT);
191
192		if (ret) {
193			hid_err(hdev, "setup data couldn't be sent\n");
194			kfree(send_buf);
195			return;
196		}
197	}
198
199	kfree(send_buf);
200}
201
202static void thrustmaster_change_handler(struct urb *urb)
203{
204	struct hid_device *hdev = urb->context;
205
206	// The wheel seems to kill himself before answering the host and therefore is violating the USB protocol...
207	if (urb->status == 0 || urb->status == -EPROTO || urb->status == -EPIPE)
208		hid_info(hdev, "Success?! The wheel should have been initialized!\n");
209	else
210		hid_warn(hdev, "URB to change wheel mode seems to have failed with error %d\n", urb->status);
211}
212
213/*
214 * Called by the USB subsystem when the wheel responses to our request
215 * to get [what it seems to be] the wheel's model.
216 *
217 * If the model id is recognized then we send an opportune USB CONTROL REQUEST
218 * to switch the wheel to its full capabilities
219 */
220static void thrustmaster_model_handler(struct urb *urb)
221{
222	struct hid_device *hdev = urb->context;
223	struct tm_wheel *tm_wheel = hid_get_drvdata(hdev);
224	uint16_t model = 0;
225	int i, ret;
226	const struct tm_wheel_info *twi = NULL;
227
228	if (urb->status) {
229		hid_err(hdev, "URB to get model id failed with error %d\n", urb->status);
230		return;
231	}
232
233	if (tm_wheel->response->type == cpu_to_le16(0x49))
234		model = le16_to_cpu(tm_wheel->response->data.a.model);
235	else if (tm_wheel->response->type == cpu_to_le16(0x47))
236		model = le16_to_cpu(tm_wheel->response->data.b.model);
237	else {
238		hid_err(hdev, "Unknown packet type 0x%x, unable to proceed further with wheel init\n", tm_wheel->response->type);
239		return;
240	}
241
242	for (i = 0; i < tm_wheels_infos_length && !twi; i++)
243		if (tm_wheels_infos[i].wheel_type == model)
244			twi = tm_wheels_infos + i;
245
246	if (twi)
247		hid_info(hdev, "Wheel with model id 0x%x is a %s\n", model, twi->wheel_name);
248	else {
249		hid_err(hdev, "Unknown wheel's model id 0x%x, unable to proceed further with wheel init\n", model);
250		return;
251	}
252
253	tm_wheel->change_request->wValue = cpu_to_le16(twi->switch_value);
254	usb_fill_control_urb(
255		tm_wheel->urb,
256		tm_wheel->usb_dev,
257		usb_sndctrlpipe(tm_wheel->usb_dev, 0),
258		(char *)tm_wheel->change_request,
259		NULL, 0, // We do not expect any response from the wheel
260		thrustmaster_change_handler,
261		hdev
262	);
263
264	ret = usb_submit_urb(tm_wheel->urb, GFP_ATOMIC);
265	if (ret)
266		hid_err(hdev, "Error %d while submitting the change URB. I am unable to initialize this wheel...\n", ret);
267}
268
269static void thrustmaster_remove(struct hid_device *hdev)
270{
271	struct tm_wheel *tm_wheel = hid_get_drvdata(hdev);
272
273	usb_kill_urb(tm_wheel->urb);
274
275	kfree(tm_wheel->change_request);
276	kfree(tm_wheel->response);
277	kfree(tm_wheel->model_request);
278	usb_free_urb(tm_wheel->urb);
279	kfree(tm_wheel);
280
281	hid_hw_stop(hdev);
282}
283
284/*
285 * Function called by HID when a hid Thrustmaster FFB wheel is connected to the host.
286 * This function starts the hid dev, tries to allocate the tm_wheel data structure and
287 * finally send an USB CONTROL REQUEST to the wheel to get [what it seems to be] its
288 * model type.
289 */
290static int thrustmaster_probe(struct hid_device *hdev, const struct hid_device_id *id)
291{
292	int ret = 0;
293	struct tm_wheel *tm_wheel = NULL;
294
295	if (!hid_is_usb(hdev))
296		return -EINVAL;
297
298	ret = hid_parse(hdev);
299	if (ret) {
300		hid_err(hdev, "parse failed with error %d\n", ret);
301		goto error0;
302	}
303
304	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF);
305	if (ret) {
306		hid_err(hdev, "hw start failed with error %d\n", ret);
307		goto error0;
308	}
309
310	// Now we allocate the tm_wheel
311	tm_wheel = kzalloc(sizeof(struct tm_wheel), GFP_KERNEL);
312	if (!tm_wheel) {
313		ret = -ENOMEM;
314		goto error1;
315	}
316
317	tm_wheel->urb = usb_alloc_urb(0, GFP_ATOMIC);
318	if (!tm_wheel->urb) {
319		ret = -ENOMEM;
320		goto error2;
321	}
322
323	tm_wheel->model_request = kmemdup(&model_request,
324					  sizeof(struct usb_ctrlrequest),
325					  GFP_KERNEL);
326	if (!tm_wheel->model_request) {
327		ret = -ENOMEM;
328		goto error3;
329	}
330
331	tm_wheel->response = kzalloc(sizeof(struct tm_wheel_response), GFP_KERNEL);
332	if (!tm_wheel->response) {
333		ret = -ENOMEM;
334		goto error4;
335	}
336
337	tm_wheel->change_request = kmemdup(&change_request,
338					   sizeof(struct usb_ctrlrequest),
339					   GFP_KERNEL);
340	if (!tm_wheel->change_request) {
341		ret = -ENOMEM;
342		goto error5;
343	}
344
345	tm_wheel->usb_dev = interface_to_usbdev(to_usb_interface(hdev->dev.parent));
346	hid_set_drvdata(hdev, tm_wheel);
347
348	thrustmaster_interrupts(hdev);
349
350	usb_fill_control_urb(
351		tm_wheel->urb,
352		tm_wheel->usb_dev,
353		usb_rcvctrlpipe(tm_wheel->usb_dev, 0),
354		(char *)tm_wheel->model_request,
355		tm_wheel->response,
356		sizeof(struct tm_wheel_response),
357		thrustmaster_model_handler,
358		hdev
359	);
360
361	ret = usb_submit_urb(tm_wheel->urb, GFP_ATOMIC);
362	if (ret) {
363		hid_err(hdev, "Error %d while submitting the URB. I am unable to initialize this wheel...\n", ret);
364		goto error6;
365	}
366
367	return ret;
368
369error6: kfree(tm_wheel->change_request);
370error5: kfree(tm_wheel->response);
371error4: kfree(tm_wheel->model_request);
372error3: usb_free_urb(tm_wheel->urb);
373error2: kfree(tm_wheel);
374error1: hid_hw_stop(hdev);
375error0:
376	return ret;
377}
378
379static const struct hid_device_id thrustmaster_devices[] = {
380	{ HID_USB_DEVICE(0x044f, 0xb65d)},
381	{}
382};
383
384MODULE_DEVICE_TABLE(hid, thrustmaster_devices);
385
386static struct hid_driver thrustmaster_driver = {
387	.name = "hid-thrustmaster",
388	.id_table = thrustmaster_devices,
389	.probe = thrustmaster_probe,
390	.remove = thrustmaster_remove,
391};
392
393module_hid_driver(thrustmaster_driver);
394
395MODULE_AUTHOR("Dario Pagani <dario.pagani.146+linuxk@gmail.com>");
396MODULE_LICENSE("GPL");
397MODULE_DESCRIPTION("Driver to initialize some steering wheel joysticks from Thrustmaster");
398