1/*
2 * Driver for IMS Passenger Control Unit Devices
3 *
4 * Copyright (C) 2013 The IMS Company
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2
8 * as published by the Free Software Foundation.
9 */
10
11#include <linux/completion.h>
12#include <linux/device.h>
13#include <linux/firmware.h>
14#include <linux/ihex.h>
15#include <linux/input.h>
16#include <linux/kernel.h>
17#include <linux/leds.h>
18#include <linux/module.h>
19#include <linux/slab.h>
20#include <linux/types.h>
21#include <linux/usb/input.h>
22#include <linux/usb/cdc.h>
23#include <asm/unaligned.h>
24
25#define IMS_PCU_KEYMAP_LEN		32
26
27struct ims_pcu_buttons {
28	struct input_dev *input;
29	char name[32];
30	char phys[32];
31	unsigned short keymap[IMS_PCU_KEYMAP_LEN];
32};
33
34struct ims_pcu_gamepad {
35	struct input_dev *input;
36	char name[32];
37	char phys[32];
38};
39
40struct ims_pcu_backlight {
41	struct led_classdev cdev;
42	struct work_struct work;
43	enum led_brightness desired_brightness;
44	char name[32];
45};
46
47#define IMS_PCU_PART_NUMBER_LEN		15
48#define IMS_PCU_SERIAL_NUMBER_LEN	8
49#define IMS_PCU_DOM_LEN			8
50#define IMS_PCU_FW_VERSION_LEN		(9 + 1)
51#define IMS_PCU_BL_VERSION_LEN		(9 + 1)
52#define IMS_PCU_BL_RESET_REASON_LEN	(2 + 1)
53
54#define IMS_PCU_PCU_B_DEVICE_ID		5
55
56#define IMS_PCU_BUF_SIZE		128
57
58struct ims_pcu {
59	struct usb_device *udev;
60	struct device *dev; /* control interface's device, used for logging */
61
62	unsigned int device_no;
63
64	bool bootloader_mode;
65
66	char part_number[IMS_PCU_PART_NUMBER_LEN];
67	char serial_number[IMS_PCU_SERIAL_NUMBER_LEN];
68	char date_of_manufacturing[IMS_PCU_DOM_LEN];
69	char fw_version[IMS_PCU_FW_VERSION_LEN];
70	char bl_version[IMS_PCU_BL_VERSION_LEN];
71	char reset_reason[IMS_PCU_BL_RESET_REASON_LEN];
72	int update_firmware_status;
73	u8 device_id;
74
75	u8 ofn_reg_addr;
76
77	struct usb_interface *ctrl_intf;
78
79	struct usb_endpoint_descriptor *ep_ctrl;
80	struct urb *urb_ctrl;
81	u8 *urb_ctrl_buf;
82	dma_addr_t ctrl_dma;
83	size_t max_ctrl_size;
84
85	struct usb_interface *data_intf;
86
87	struct usb_endpoint_descriptor *ep_in;
88	struct urb *urb_in;
89	u8 *urb_in_buf;
90	dma_addr_t read_dma;
91	size_t max_in_size;
92
93	struct usb_endpoint_descriptor *ep_out;
94	u8 *urb_out_buf;
95	size_t max_out_size;
96
97	u8 read_buf[IMS_PCU_BUF_SIZE];
98	u8 read_pos;
99	u8 check_sum;
100	bool have_stx;
101	bool have_dle;
102
103	u8 cmd_buf[IMS_PCU_BUF_SIZE];
104	u8 ack_id;
105	u8 expected_response;
106	u8 cmd_buf_len;
107	struct completion cmd_done;
108	struct mutex cmd_mutex;
109
110	u32 fw_start_addr;
111	u32 fw_end_addr;
112	struct completion async_firmware_done;
113
114	struct ims_pcu_buttons buttons;
115	struct ims_pcu_gamepad *gamepad;
116	struct ims_pcu_backlight backlight;
117
118	bool setup_complete; /* Input and LED devices have been created */
119};
120
121
122/*********************************************************************
123 *             Buttons Input device support                          *
124 *********************************************************************/
125
126static const unsigned short ims_pcu_keymap_1[] = {
127	[1] = KEY_ATTENDANT_OFF,
128	[2] = KEY_ATTENDANT_ON,
129	[3] = KEY_LIGHTS_TOGGLE,
130	[4] = KEY_VOLUMEUP,
131	[5] = KEY_VOLUMEDOWN,
132	[6] = KEY_INFO,
133};
134
135static const unsigned short ims_pcu_keymap_2[] = {
136	[4] = KEY_VOLUMEUP,
137	[5] = KEY_VOLUMEDOWN,
138	[6] = KEY_INFO,
139};
140
141static const unsigned short ims_pcu_keymap_3[] = {
142	[1] = KEY_HOMEPAGE,
143	[2] = KEY_ATTENDANT_TOGGLE,
144	[3] = KEY_LIGHTS_TOGGLE,
145	[4] = KEY_VOLUMEUP,
146	[5] = KEY_VOLUMEDOWN,
147	[6] = KEY_DISPLAYTOGGLE,
148	[18] = KEY_PLAYPAUSE,
149};
150
151static const unsigned short ims_pcu_keymap_4[] = {
152	[1] = KEY_ATTENDANT_OFF,
153	[2] = KEY_ATTENDANT_ON,
154	[3] = KEY_LIGHTS_TOGGLE,
155	[4] = KEY_VOLUMEUP,
156	[5] = KEY_VOLUMEDOWN,
157	[6] = KEY_INFO,
158	[18] = KEY_PLAYPAUSE,
159};
160
161static const unsigned short ims_pcu_keymap_5[] = {
162	[1] = KEY_ATTENDANT_OFF,
163	[2] = KEY_ATTENDANT_ON,
164	[3] = KEY_LIGHTS_TOGGLE,
165};
166
167struct ims_pcu_device_info {
168	const unsigned short *keymap;
169	size_t keymap_len;
170	bool has_gamepad;
171};
172
173#define IMS_PCU_DEVINFO(_n, _gamepad)				\
174	[_n] = {						\
175		.keymap = ims_pcu_keymap_##_n,			\
176		.keymap_len = ARRAY_SIZE(ims_pcu_keymap_##_n),	\
177		.has_gamepad = _gamepad,			\
178	}
179
180static const struct ims_pcu_device_info ims_pcu_device_info[] = {
181	IMS_PCU_DEVINFO(1, true),
182	IMS_PCU_DEVINFO(2, true),
183	IMS_PCU_DEVINFO(3, true),
184	IMS_PCU_DEVINFO(4, true),
185	IMS_PCU_DEVINFO(5, false),
186};
187
188static void ims_pcu_buttons_report(struct ims_pcu *pcu, u32 data)
189{
190	struct ims_pcu_buttons *buttons = &pcu->buttons;
191	struct input_dev *input = buttons->input;
192	int i;
193
194	for (i = 0; i < 32; i++) {
195		unsigned short keycode = buttons->keymap[i];
196
197		if (keycode != KEY_RESERVED)
198			input_report_key(input, keycode, data & (1UL << i));
199	}
200
201	input_sync(input);
202}
203
204static int ims_pcu_setup_buttons(struct ims_pcu *pcu,
205				 const unsigned short *keymap,
206				 size_t keymap_len)
207{
208	struct ims_pcu_buttons *buttons = &pcu->buttons;
209	struct input_dev *input;
210	int i;
211	int error;
212
213	input = input_allocate_device();
214	if (!input) {
215		dev_err(pcu->dev,
216			"Not enough memory for input input device\n");
217		return -ENOMEM;
218	}
219
220	snprintf(buttons->name, sizeof(buttons->name),
221		 "IMS PCU#%d Button Interface", pcu->device_no);
222
223	usb_make_path(pcu->udev, buttons->phys, sizeof(buttons->phys));
224	strlcat(buttons->phys, "/input0", sizeof(buttons->phys));
225
226	memcpy(buttons->keymap, keymap, sizeof(*keymap) * keymap_len);
227
228	input->name = buttons->name;
229	input->phys = buttons->phys;
230	usb_to_input_id(pcu->udev, &input->id);
231	input->dev.parent = &pcu->ctrl_intf->dev;
232
233	input->keycode = buttons->keymap;
234	input->keycodemax = ARRAY_SIZE(buttons->keymap);
235	input->keycodesize = sizeof(buttons->keymap[0]);
236
237	__set_bit(EV_KEY, input->evbit);
238	for (i = 0; i < IMS_PCU_KEYMAP_LEN; i++)
239		__set_bit(buttons->keymap[i], input->keybit);
240	__clear_bit(KEY_RESERVED, input->keybit);
241
242	error = input_register_device(input);
243	if (error) {
244		dev_err(pcu->dev,
245			"Failed to register buttons input device: %d\n",
246			error);
247		input_free_device(input);
248		return error;
249	}
250
251	buttons->input = input;
252	return 0;
253}
254
255static void ims_pcu_destroy_buttons(struct ims_pcu *pcu)
256{
257	struct ims_pcu_buttons *buttons = &pcu->buttons;
258
259	input_unregister_device(buttons->input);
260}
261
262
263/*********************************************************************
264 *             Gamepad Input device support                          *
265 *********************************************************************/
266
267static void ims_pcu_gamepad_report(struct ims_pcu *pcu, u32 data)
268{
269	struct ims_pcu_gamepad *gamepad = pcu->gamepad;
270	struct input_dev *input = gamepad->input;
271	int x, y;
272
273	x = !!(data & (1 << 14)) - !!(data & (1 << 13));
274	y = !!(data & (1 << 12)) - !!(data & (1 << 11));
275
276	input_report_abs(input, ABS_X, x);
277	input_report_abs(input, ABS_Y, y);
278
279	input_report_key(input, BTN_A, data & (1 << 7));
280	input_report_key(input, BTN_B, data & (1 << 8));
281	input_report_key(input, BTN_X, data & (1 << 9));
282	input_report_key(input, BTN_Y, data & (1 << 10));
283	input_report_key(input, BTN_START, data & (1 << 15));
284	input_report_key(input, BTN_SELECT, data & (1 << 16));
285
286	input_sync(input);
287}
288
289static int ims_pcu_setup_gamepad(struct ims_pcu *pcu)
290{
291	struct ims_pcu_gamepad *gamepad;
292	struct input_dev *input;
293	int error;
294
295	gamepad = kzalloc(sizeof(struct ims_pcu_gamepad), GFP_KERNEL);
296	input = input_allocate_device();
297	if (!gamepad || !input) {
298		dev_err(pcu->dev,
299			"Not enough memory for gamepad device\n");
300		error = -ENOMEM;
301		goto err_free_mem;
302	}
303
304	gamepad->input = input;
305
306	snprintf(gamepad->name, sizeof(gamepad->name),
307		 "IMS PCU#%d Gamepad Interface", pcu->device_no);
308
309	usb_make_path(pcu->udev, gamepad->phys, sizeof(gamepad->phys));
310	strlcat(gamepad->phys, "/input1", sizeof(gamepad->phys));
311
312	input->name = gamepad->name;
313	input->phys = gamepad->phys;
314	usb_to_input_id(pcu->udev, &input->id);
315	input->dev.parent = &pcu->ctrl_intf->dev;
316
317	__set_bit(EV_KEY, input->evbit);
318	__set_bit(BTN_A, input->keybit);
319	__set_bit(BTN_B, input->keybit);
320	__set_bit(BTN_X, input->keybit);
321	__set_bit(BTN_Y, input->keybit);
322	__set_bit(BTN_START, input->keybit);
323	__set_bit(BTN_SELECT, input->keybit);
324
325	__set_bit(EV_ABS, input->evbit);
326	input_set_abs_params(input, ABS_X, -1, 1, 0, 0);
327	input_set_abs_params(input, ABS_Y, -1, 1, 0, 0);
328
329	error = input_register_device(input);
330	if (error) {
331		dev_err(pcu->dev,
332			"Failed to register gamepad input device: %d\n",
333			error);
334		goto err_free_mem;
335	}
336
337	pcu->gamepad = gamepad;
338	return 0;
339
340err_free_mem:
341	input_free_device(input);
342	kfree(gamepad);
343	return -ENOMEM;
344}
345
346static void ims_pcu_destroy_gamepad(struct ims_pcu *pcu)
347{
348	struct ims_pcu_gamepad *gamepad = pcu->gamepad;
349
350	input_unregister_device(gamepad->input);
351	kfree(gamepad);
352}
353
354
355/*********************************************************************
356 *             PCU Communication protocol handling                   *
357 *********************************************************************/
358
359#define IMS_PCU_PROTOCOL_STX		0x02
360#define IMS_PCU_PROTOCOL_ETX		0x03
361#define IMS_PCU_PROTOCOL_DLE		0x10
362
363/* PCU commands */
364#define IMS_PCU_CMD_STATUS		0xa0
365#define IMS_PCU_CMD_PCU_RESET		0xa1
366#define IMS_PCU_CMD_RESET_REASON	0xa2
367#define IMS_PCU_CMD_SEND_BUTTONS	0xa3
368#define IMS_PCU_CMD_JUMP_TO_BTLDR	0xa4
369#define IMS_PCU_CMD_GET_INFO		0xa5
370#define IMS_PCU_CMD_SET_BRIGHTNESS	0xa6
371#define IMS_PCU_CMD_EEPROM		0xa7
372#define IMS_PCU_CMD_GET_FW_VERSION	0xa8
373#define IMS_PCU_CMD_GET_BL_VERSION	0xa9
374#define IMS_PCU_CMD_SET_INFO		0xab
375#define IMS_PCU_CMD_GET_BRIGHTNESS	0xac
376#define IMS_PCU_CMD_GET_DEVICE_ID	0xae
377#define IMS_PCU_CMD_SPECIAL_INFO	0xb0
378#define IMS_PCU_CMD_BOOTLOADER		0xb1	/* Pass data to bootloader */
379#define IMS_PCU_CMD_OFN_SET_CONFIG	0xb3
380#define IMS_PCU_CMD_OFN_GET_CONFIG	0xb4
381
382/* PCU responses */
383#define IMS_PCU_RSP_STATUS		0xc0
384#define IMS_PCU_RSP_PCU_RESET		0	/* Originally 0xc1 */
385#define IMS_PCU_RSP_RESET_REASON	0xc2
386#define IMS_PCU_RSP_SEND_BUTTONS	0xc3
387#define IMS_PCU_RSP_JUMP_TO_BTLDR	0	/* Originally 0xc4 */
388#define IMS_PCU_RSP_GET_INFO		0xc5
389#define IMS_PCU_RSP_SET_BRIGHTNESS	0xc6
390#define IMS_PCU_RSP_EEPROM		0xc7
391#define IMS_PCU_RSP_GET_FW_VERSION	0xc8
392#define IMS_PCU_RSP_GET_BL_VERSION	0xc9
393#define IMS_PCU_RSP_SET_INFO		0xcb
394#define IMS_PCU_RSP_GET_BRIGHTNESS	0xcc
395#define IMS_PCU_RSP_CMD_INVALID		0xcd
396#define IMS_PCU_RSP_GET_DEVICE_ID	0xce
397#define IMS_PCU_RSP_SPECIAL_INFO	0xd0
398#define IMS_PCU_RSP_BOOTLOADER		0xd1	/* Bootloader response */
399#define IMS_PCU_RSP_OFN_SET_CONFIG	0xd2
400#define IMS_PCU_RSP_OFN_GET_CONFIG	0xd3
401
402
403#define IMS_PCU_RSP_EVNT_BUTTONS	0xe0	/* Unsolicited, button state */
404#define IMS_PCU_GAMEPAD_MASK		0x0001ff80UL	/* Bits 7 through 16 */
405
406
407#define IMS_PCU_MIN_PACKET_LEN		3
408#define IMS_PCU_DATA_OFFSET		2
409
410#define IMS_PCU_CMD_WRITE_TIMEOUT	100 /* msec */
411#define IMS_PCU_CMD_RESPONSE_TIMEOUT	500 /* msec */
412
413static void ims_pcu_report_events(struct ims_pcu *pcu)
414{
415	u32 data = get_unaligned_be32(&pcu->read_buf[3]);
416
417	ims_pcu_buttons_report(pcu, data & ~IMS_PCU_GAMEPAD_MASK);
418	if (pcu->gamepad)
419		ims_pcu_gamepad_report(pcu, data);
420}
421
422static void ims_pcu_handle_response(struct ims_pcu *pcu)
423{
424	switch (pcu->read_buf[0]) {
425	case IMS_PCU_RSP_EVNT_BUTTONS:
426		if (likely(pcu->setup_complete))
427			ims_pcu_report_events(pcu);
428		break;
429
430	default:
431		/*
432		 * See if we got command completion.
433		 * If both the sequence and response code match save
434		 * the data and signal completion.
435		 */
436		if (pcu->read_buf[0] == pcu->expected_response &&
437		    pcu->read_buf[1] == pcu->ack_id - 1) {
438
439			memcpy(pcu->cmd_buf, pcu->read_buf, pcu->read_pos);
440			pcu->cmd_buf_len = pcu->read_pos;
441			complete(&pcu->cmd_done);
442		}
443		break;
444	}
445}
446
447static void ims_pcu_process_data(struct ims_pcu *pcu, struct urb *urb)
448{
449	int i;
450
451	for (i = 0; i < urb->actual_length; i++) {
452		u8 data = pcu->urb_in_buf[i];
453
454		/* Skip everything until we get Start Xmit */
455		if (!pcu->have_stx && data != IMS_PCU_PROTOCOL_STX)
456			continue;
457
458		if (pcu->have_dle) {
459			pcu->have_dle = false;
460			pcu->read_buf[pcu->read_pos++] = data;
461			pcu->check_sum += data;
462			continue;
463		}
464
465		switch (data) {
466		case IMS_PCU_PROTOCOL_STX:
467			if (pcu->have_stx)
468				dev_warn(pcu->dev,
469					 "Unexpected STX at byte %d, discarding old data\n",
470					 pcu->read_pos);
471			pcu->have_stx = true;
472			pcu->have_dle = false;
473			pcu->read_pos = 0;
474			pcu->check_sum = 0;
475			break;
476
477		case IMS_PCU_PROTOCOL_DLE:
478			pcu->have_dle = true;
479			break;
480
481		case IMS_PCU_PROTOCOL_ETX:
482			if (pcu->read_pos < IMS_PCU_MIN_PACKET_LEN) {
483				dev_warn(pcu->dev,
484					 "Short packet received (%d bytes), ignoring\n",
485					 pcu->read_pos);
486			} else if (pcu->check_sum != 0) {
487				dev_warn(pcu->dev,
488					 "Invalid checksum in packet (%d bytes), ignoring\n",
489					 pcu->read_pos);
490			} else {
491				ims_pcu_handle_response(pcu);
492			}
493
494			pcu->have_stx = false;
495			pcu->have_dle = false;
496			pcu->read_pos = 0;
497			break;
498
499		default:
500			pcu->read_buf[pcu->read_pos++] = data;
501			pcu->check_sum += data;
502			break;
503		}
504	}
505}
506
507static bool ims_pcu_byte_needs_escape(u8 byte)
508{
509	return byte == IMS_PCU_PROTOCOL_STX ||
510	       byte == IMS_PCU_PROTOCOL_ETX ||
511	       byte == IMS_PCU_PROTOCOL_DLE;
512}
513
514static int ims_pcu_send_cmd_chunk(struct ims_pcu *pcu,
515				  u8 command, int chunk, int len)
516{
517	int error;
518
519	error = usb_bulk_msg(pcu->udev,
520			     usb_sndbulkpipe(pcu->udev,
521					     pcu->ep_out->bEndpointAddress),
522			     pcu->urb_out_buf, len,
523			     NULL, IMS_PCU_CMD_WRITE_TIMEOUT);
524	if (error < 0) {
525		dev_dbg(pcu->dev,
526			"Sending 0x%02x command failed at chunk %d: %d\n",
527			command, chunk, error);
528		return error;
529	}
530
531	return 0;
532}
533
534static int ims_pcu_send_command(struct ims_pcu *pcu,
535				u8 command, const u8 *data, int len)
536{
537	int count = 0;
538	int chunk = 0;
539	int delta;
540	int i;
541	int error;
542	u8 csum = 0;
543	u8 ack_id;
544
545	pcu->urb_out_buf[count++] = IMS_PCU_PROTOCOL_STX;
546
547	/* We know the command need not be escaped */
548	pcu->urb_out_buf[count++] = command;
549	csum += command;
550
551	ack_id = pcu->ack_id++;
552	if (ack_id == 0xff)
553		ack_id = pcu->ack_id++;
554
555	if (ims_pcu_byte_needs_escape(ack_id))
556		pcu->urb_out_buf[count++] = IMS_PCU_PROTOCOL_DLE;
557
558	pcu->urb_out_buf[count++] = ack_id;
559	csum += ack_id;
560
561	for (i = 0; i < len; i++) {
562
563		delta = ims_pcu_byte_needs_escape(data[i]) ? 2 : 1;
564		if (count + delta >= pcu->max_out_size) {
565			error = ims_pcu_send_cmd_chunk(pcu, command,
566						       ++chunk, count);
567			if (error)
568				return error;
569
570			count = 0;
571		}
572
573		if (delta == 2)
574			pcu->urb_out_buf[count++] = IMS_PCU_PROTOCOL_DLE;
575
576		pcu->urb_out_buf[count++] = data[i];
577		csum += data[i];
578	}
579
580	csum = 1 + ~csum;
581
582	delta = ims_pcu_byte_needs_escape(csum) ? 3 : 2;
583	if (count + delta >= pcu->max_out_size) {
584		error = ims_pcu_send_cmd_chunk(pcu, command, ++chunk, count);
585		if (error)
586			return error;
587
588		count = 0;
589	}
590
591	if (delta == 3)
592		pcu->urb_out_buf[count++] = IMS_PCU_PROTOCOL_DLE;
593
594	pcu->urb_out_buf[count++] = csum;
595	pcu->urb_out_buf[count++] = IMS_PCU_PROTOCOL_ETX;
596
597	return ims_pcu_send_cmd_chunk(pcu, command, ++chunk, count);
598}
599
600static int __ims_pcu_execute_command(struct ims_pcu *pcu,
601				     u8 command, const void *data, size_t len,
602				     u8 expected_response, int response_time)
603{
604	int error;
605
606	pcu->expected_response = expected_response;
607	init_completion(&pcu->cmd_done);
608
609	error = ims_pcu_send_command(pcu, command, data, len);
610	if (error)
611		return error;
612
613	if (expected_response &&
614	    !wait_for_completion_timeout(&pcu->cmd_done,
615					 msecs_to_jiffies(response_time))) {
616		dev_dbg(pcu->dev, "Command 0x%02x timed out\n", command);
617		return -ETIMEDOUT;
618	}
619
620	return 0;
621}
622
623#define ims_pcu_execute_command(pcu, code, data, len)			\
624	__ims_pcu_execute_command(pcu,					\
625				  IMS_PCU_CMD_##code, data, len,	\
626				  IMS_PCU_RSP_##code,			\
627				  IMS_PCU_CMD_RESPONSE_TIMEOUT)
628
629#define ims_pcu_execute_query(pcu, code)				\
630	ims_pcu_execute_command(pcu, code, NULL, 0)
631
632/* Bootloader commands */
633#define IMS_PCU_BL_CMD_QUERY_DEVICE	0xa1
634#define IMS_PCU_BL_CMD_UNLOCK_CONFIG	0xa2
635#define IMS_PCU_BL_CMD_ERASE_APP	0xa3
636#define IMS_PCU_BL_CMD_PROGRAM_DEVICE	0xa4
637#define IMS_PCU_BL_CMD_PROGRAM_COMPLETE	0xa5
638#define IMS_PCU_BL_CMD_READ_APP		0xa6
639#define IMS_PCU_BL_CMD_RESET_DEVICE	0xa7
640#define IMS_PCU_BL_CMD_LAUNCH_APP	0xa8
641
642/* Bootloader commands */
643#define IMS_PCU_BL_RSP_QUERY_DEVICE	0xc1
644#define IMS_PCU_BL_RSP_UNLOCK_CONFIG	0xc2
645#define IMS_PCU_BL_RSP_ERASE_APP	0xc3
646#define IMS_PCU_BL_RSP_PROGRAM_DEVICE	0xc4
647#define IMS_PCU_BL_RSP_PROGRAM_COMPLETE	0xc5
648#define IMS_PCU_BL_RSP_READ_APP		0xc6
649#define IMS_PCU_BL_RSP_RESET_DEVICE	0	/* originally 0xa7 */
650#define IMS_PCU_BL_RSP_LAUNCH_APP	0	/* originally 0xa8 */
651
652#define IMS_PCU_BL_DATA_OFFSET		3
653
654static int __ims_pcu_execute_bl_command(struct ims_pcu *pcu,
655				        u8 command, const void *data, size_t len,
656				        u8 expected_response, int response_time)
657{
658	int error;
659
660	pcu->cmd_buf[0] = command;
661	if (data)
662		memcpy(&pcu->cmd_buf[1], data, len);
663
664	error = __ims_pcu_execute_command(pcu,
665				IMS_PCU_CMD_BOOTLOADER, pcu->cmd_buf, len + 1,
666				expected_response ? IMS_PCU_RSP_BOOTLOADER : 0,
667				response_time);
668	if (error) {
669		dev_err(pcu->dev,
670			"Failure when sending 0x%02x command to bootloader, error: %d\n",
671			pcu->cmd_buf[0], error);
672		return error;
673	}
674
675	if (expected_response && pcu->cmd_buf[2] != expected_response) {
676		dev_err(pcu->dev,
677			"Unexpected response from bootloader: 0x%02x, wanted 0x%02x\n",
678			pcu->cmd_buf[2], expected_response);
679		return -EINVAL;
680	}
681
682	return 0;
683}
684
685#define ims_pcu_execute_bl_command(pcu, code, data, len, timeout)	\
686	__ims_pcu_execute_bl_command(pcu,				\
687				     IMS_PCU_BL_CMD_##code, data, len,	\
688				     IMS_PCU_BL_RSP_##code, timeout)	\
689
690#define IMS_PCU_INFO_PART_OFFSET	2
691#define IMS_PCU_INFO_DOM_OFFSET		17
692#define IMS_PCU_INFO_SERIAL_OFFSET	25
693
694#define IMS_PCU_SET_INFO_SIZE		31
695
696static int ims_pcu_get_info(struct ims_pcu *pcu)
697{
698	int error;
699
700	error = ims_pcu_execute_query(pcu, GET_INFO);
701	if (error) {
702		dev_err(pcu->dev,
703			"GET_INFO command failed, error: %d\n", error);
704		return error;
705	}
706
707	memcpy(pcu->part_number,
708	       &pcu->cmd_buf[IMS_PCU_INFO_PART_OFFSET],
709	       sizeof(pcu->part_number));
710	memcpy(pcu->date_of_manufacturing,
711	       &pcu->cmd_buf[IMS_PCU_INFO_DOM_OFFSET],
712	       sizeof(pcu->date_of_manufacturing));
713	memcpy(pcu->serial_number,
714	       &pcu->cmd_buf[IMS_PCU_INFO_SERIAL_OFFSET],
715	       sizeof(pcu->serial_number));
716
717	return 0;
718}
719
720static int ims_pcu_set_info(struct ims_pcu *pcu)
721{
722	int error;
723
724	memcpy(&pcu->cmd_buf[IMS_PCU_INFO_PART_OFFSET],
725	       pcu->part_number, sizeof(pcu->part_number));
726	memcpy(&pcu->cmd_buf[IMS_PCU_INFO_DOM_OFFSET],
727	       pcu->date_of_manufacturing, sizeof(pcu->date_of_manufacturing));
728	memcpy(&pcu->cmd_buf[IMS_PCU_INFO_SERIAL_OFFSET],
729	       pcu->serial_number, sizeof(pcu->serial_number));
730
731	error = ims_pcu_execute_command(pcu, SET_INFO,
732					&pcu->cmd_buf[IMS_PCU_DATA_OFFSET],
733					IMS_PCU_SET_INFO_SIZE);
734	if (error) {
735		dev_err(pcu->dev,
736			"Failed to update device information, error: %d\n",
737			error);
738		return error;
739	}
740
741	return 0;
742}
743
744static int ims_pcu_switch_to_bootloader(struct ims_pcu *pcu)
745{
746	int error;
747
748	/* Execute jump to the bootoloader */
749	error = ims_pcu_execute_command(pcu, JUMP_TO_BTLDR, NULL, 0);
750	if (error) {
751		dev_err(pcu->dev,
752			"Failure when sending JUMP TO BOOLTLOADER command, error: %d\n",
753			error);
754		return error;
755	}
756
757	return 0;
758}
759
760/*********************************************************************
761 *             Firmware Update handling                              *
762 *********************************************************************/
763
764#define IMS_PCU_FIRMWARE_NAME	"imspcu.fw"
765
766struct ims_pcu_flash_fmt {
767	__le32 addr;
768	u8 len;
769	u8 data[];
770};
771
772static unsigned int ims_pcu_count_fw_records(const struct firmware *fw)
773{
774	const struct ihex_binrec *rec = (const struct ihex_binrec *)fw->data;
775	unsigned int count = 0;
776
777	while (rec) {
778		count++;
779		rec = ihex_next_binrec(rec);
780	}
781
782	return count;
783}
784
785static int ims_pcu_verify_block(struct ims_pcu *pcu,
786				u32 addr, u8 len, const u8 *data)
787{
788	struct ims_pcu_flash_fmt *fragment;
789	int error;
790
791	fragment = (void *)&pcu->cmd_buf[1];
792	put_unaligned_le32(addr, &fragment->addr);
793	fragment->len = len;
794
795	error = ims_pcu_execute_bl_command(pcu, READ_APP, NULL, 5,
796					IMS_PCU_CMD_RESPONSE_TIMEOUT);
797	if (error) {
798		dev_err(pcu->dev,
799			"Failed to retrieve block at 0x%08x, len %d, error: %d\n",
800			addr, len, error);
801		return error;
802	}
803
804	fragment = (void *)&pcu->cmd_buf[IMS_PCU_BL_DATA_OFFSET];
805	if (get_unaligned_le32(&fragment->addr) != addr ||
806	    fragment->len != len) {
807		dev_err(pcu->dev,
808			"Wrong block when retrieving 0x%08x (0x%08x), len %d (%d)\n",
809			addr, get_unaligned_le32(&fragment->addr),
810			len, fragment->len);
811		return -EINVAL;
812	}
813
814	if (memcmp(fragment->data, data, len)) {
815		dev_err(pcu->dev,
816			"Mismatch in block at 0x%08x, len %d\n",
817			addr, len);
818		return -EINVAL;
819	}
820
821	return 0;
822}
823
824static int ims_pcu_flash_firmware(struct ims_pcu *pcu,
825				  const struct firmware *fw,
826				  unsigned int n_fw_records)
827{
828	const struct ihex_binrec *rec = (const struct ihex_binrec *)fw->data;
829	struct ims_pcu_flash_fmt *fragment;
830	unsigned int count = 0;
831	u32 addr;
832	u8 len;
833	int error;
834
835	error = ims_pcu_execute_bl_command(pcu, ERASE_APP, NULL, 0, 2000);
836	if (error) {
837		dev_err(pcu->dev,
838			"Failed to erase application image, error: %d\n",
839			error);
840		return error;
841	}
842
843	while (rec) {
844		/*
845		 * The firmware format is messed up for some reason.
846		 * The address twice that of what is needed for some
847		 * reason and we end up overwriting half of the data
848		 * with the next record.
849		 */
850		addr = be32_to_cpu(rec->addr) / 2;
851		len = be16_to_cpu(rec->len);
852
853		fragment = (void *)&pcu->cmd_buf[1];
854		put_unaligned_le32(addr, &fragment->addr);
855		fragment->len = len;
856		memcpy(fragment->data, rec->data, len);
857
858		error = ims_pcu_execute_bl_command(pcu, PROGRAM_DEVICE,
859						NULL, len + 5,
860						IMS_PCU_CMD_RESPONSE_TIMEOUT);
861		if (error) {
862			dev_err(pcu->dev,
863				"Failed to write block at 0x%08x, len %d, error: %d\n",
864				addr, len, error);
865			return error;
866		}
867
868		if (addr >= pcu->fw_start_addr && addr < pcu->fw_end_addr) {
869			error = ims_pcu_verify_block(pcu, addr, len, rec->data);
870			if (error)
871				return error;
872		}
873
874		count++;
875		pcu->update_firmware_status = (count * 100) / n_fw_records;
876
877		rec = ihex_next_binrec(rec);
878	}
879
880	error = ims_pcu_execute_bl_command(pcu, PROGRAM_COMPLETE,
881					    NULL, 0, 2000);
882	if (error)
883		dev_err(pcu->dev,
884			"Failed to send PROGRAM_COMPLETE, error: %d\n",
885			error);
886
887	return 0;
888}
889
890static int ims_pcu_handle_firmware_update(struct ims_pcu *pcu,
891					  const struct firmware *fw)
892{
893	unsigned int n_fw_records;
894	int retval;
895
896	dev_info(pcu->dev, "Updating firmware %s, size: %zu\n",
897		 IMS_PCU_FIRMWARE_NAME, fw->size);
898
899	n_fw_records = ims_pcu_count_fw_records(fw);
900
901	retval = ims_pcu_flash_firmware(pcu, fw, n_fw_records);
902	if (retval)
903		goto out;
904
905	retval = ims_pcu_execute_bl_command(pcu, LAUNCH_APP, NULL, 0, 0);
906	if (retval)
907		dev_err(pcu->dev,
908			"Failed to start application image, error: %d\n",
909			retval);
910
911out:
912	pcu->update_firmware_status = retval;
913	sysfs_notify(&pcu->dev->kobj, NULL, "update_firmware_status");
914	return retval;
915}
916
917static void ims_pcu_process_async_firmware(const struct firmware *fw,
918					   void *context)
919{
920	struct ims_pcu *pcu = context;
921	int error;
922
923	if (!fw) {
924		dev_err(pcu->dev, "Failed to get firmware %s\n",
925			IMS_PCU_FIRMWARE_NAME);
926		goto out;
927	}
928
929	error = ihex_validate_fw(fw);
930	if (error) {
931		dev_err(pcu->dev, "Firmware %s is invalid\n",
932			IMS_PCU_FIRMWARE_NAME);
933		goto out;
934	}
935
936	mutex_lock(&pcu->cmd_mutex);
937	ims_pcu_handle_firmware_update(pcu, fw);
938	mutex_unlock(&pcu->cmd_mutex);
939
940	release_firmware(fw);
941
942out:
943	complete(&pcu->async_firmware_done);
944}
945
946/*********************************************************************
947 *             Backlight LED device support                          *
948 *********************************************************************/
949
950#define IMS_PCU_MAX_BRIGHTNESS		31998
951
952static void ims_pcu_backlight_work(struct work_struct *work)
953{
954	struct ims_pcu_backlight *backlight =
955			container_of(work, struct ims_pcu_backlight, work);
956	struct ims_pcu *pcu =
957			container_of(backlight, struct ims_pcu, backlight);
958	int desired_brightness = backlight->desired_brightness;
959	__le16 br_val = cpu_to_le16(desired_brightness);
960	int error;
961
962	mutex_lock(&pcu->cmd_mutex);
963
964	error = ims_pcu_execute_command(pcu, SET_BRIGHTNESS,
965					&br_val, sizeof(br_val));
966	if (error && error != -ENODEV)
967		dev_warn(pcu->dev,
968			 "Failed to set desired brightness %u, error: %d\n",
969			 desired_brightness, error);
970
971	mutex_unlock(&pcu->cmd_mutex);
972}
973
974static void ims_pcu_backlight_set_brightness(struct led_classdev *cdev,
975					     enum led_brightness value)
976{
977	struct ims_pcu_backlight *backlight =
978			container_of(cdev, struct ims_pcu_backlight, cdev);
979
980	backlight->desired_brightness = value;
981	schedule_work(&backlight->work);
982}
983
984static enum led_brightness
985ims_pcu_backlight_get_brightness(struct led_classdev *cdev)
986{
987	struct ims_pcu_backlight *backlight =
988			container_of(cdev, struct ims_pcu_backlight, cdev);
989	struct ims_pcu *pcu =
990			container_of(backlight, struct ims_pcu, backlight);
991	int brightness;
992	int error;
993
994	mutex_lock(&pcu->cmd_mutex);
995
996	error = ims_pcu_execute_query(pcu, GET_BRIGHTNESS);
997	if (error) {
998		dev_warn(pcu->dev,
999			 "Failed to get current brightness, error: %d\n",
1000			 error);
1001		/* Assume the LED is OFF */
1002		brightness = LED_OFF;
1003	} else {
1004		brightness =
1005			get_unaligned_le16(&pcu->cmd_buf[IMS_PCU_DATA_OFFSET]);
1006	}
1007
1008	mutex_unlock(&pcu->cmd_mutex);
1009
1010	return brightness;
1011}
1012
1013static int ims_pcu_setup_backlight(struct ims_pcu *pcu)
1014{
1015	struct ims_pcu_backlight *backlight = &pcu->backlight;
1016	int error;
1017
1018	INIT_WORK(&backlight->work, ims_pcu_backlight_work);
1019	snprintf(backlight->name, sizeof(backlight->name),
1020		 "pcu%d::kbd_backlight", pcu->device_no);
1021
1022	backlight->cdev.name = backlight->name;
1023	backlight->cdev.max_brightness = IMS_PCU_MAX_BRIGHTNESS;
1024	backlight->cdev.brightness_get = ims_pcu_backlight_get_brightness;
1025	backlight->cdev.brightness_set = ims_pcu_backlight_set_brightness;
1026
1027	error = led_classdev_register(pcu->dev, &backlight->cdev);
1028	if (error) {
1029		dev_err(pcu->dev,
1030			"Failed to register backlight LED device, error: %d\n",
1031			error);
1032		return error;
1033	}
1034
1035	return 0;
1036}
1037
1038static void ims_pcu_destroy_backlight(struct ims_pcu *pcu)
1039{
1040	struct ims_pcu_backlight *backlight = &pcu->backlight;
1041
1042	led_classdev_unregister(&backlight->cdev);
1043	cancel_work_sync(&backlight->work);
1044}
1045
1046
1047/*********************************************************************
1048 *             Sysfs attributes handling                             *
1049 *********************************************************************/
1050
1051struct ims_pcu_attribute {
1052	struct device_attribute dattr;
1053	size_t field_offset;
1054	int field_length;
1055};
1056
1057static ssize_t ims_pcu_attribute_show(struct device *dev,
1058				      struct device_attribute *dattr,
1059				      char *buf)
1060{
1061	struct usb_interface *intf = to_usb_interface(dev);
1062	struct ims_pcu *pcu = usb_get_intfdata(intf);
1063	struct ims_pcu_attribute *attr =
1064			container_of(dattr, struct ims_pcu_attribute, dattr);
1065	char *field = (char *)pcu + attr->field_offset;
1066
1067	return scnprintf(buf, PAGE_SIZE, "%.*s\n", attr->field_length, field);
1068}
1069
1070static ssize_t ims_pcu_attribute_store(struct device *dev,
1071				       struct device_attribute *dattr,
1072				       const char *buf, size_t count)
1073{
1074
1075	struct usb_interface *intf = to_usb_interface(dev);
1076	struct ims_pcu *pcu = usb_get_intfdata(intf);
1077	struct ims_pcu_attribute *attr =
1078			container_of(dattr, struct ims_pcu_attribute, dattr);
1079	char *field = (char *)pcu + attr->field_offset;
1080	size_t data_len;
1081	int error;
1082
1083	if (count > attr->field_length)
1084		return -EINVAL;
1085
1086	data_len = strnlen(buf, attr->field_length);
1087	if (data_len > attr->field_length)
1088		return -EINVAL;
1089
1090	error = mutex_lock_interruptible(&pcu->cmd_mutex);
1091	if (error)
1092		return error;
1093
1094	memset(field, 0, attr->field_length);
1095	memcpy(field, buf, data_len);
1096
1097	error = ims_pcu_set_info(pcu);
1098
1099	/*
1100	 * Even if update failed, let's fetch the info again as we just
1101	 * clobbered one of the fields.
1102	 */
1103	ims_pcu_get_info(pcu);
1104
1105	mutex_unlock(&pcu->cmd_mutex);
1106
1107	return error < 0 ? error : count;
1108}
1109
1110#define IMS_PCU_ATTR(_field, _mode)					\
1111struct ims_pcu_attribute ims_pcu_attr_##_field = {			\
1112	.dattr = __ATTR(_field, _mode,					\
1113			ims_pcu_attribute_show,				\
1114			ims_pcu_attribute_store),			\
1115	.field_offset = offsetof(struct ims_pcu, _field),		\
1116	.field_length = sizeof(((struct ims_pcu *)NULL)->_field),	\
1117}
1118
1119#define IMS_PCU_RO_ATTR(_field)						\
1120		IMS_PCU_ATTR(_field, S_IRUGO)
1121#define IMS_PCU_RW_ATTR(_field)						\
1122		IMS_PCU_ATTR(_field, S_IRUGO | S_IWUSR)
1123
1124static IMS_PCU_RW_ATTR(part_number);
1125static IMS_PCU_RW_ATTR(serial_number);
1126static IMS_PCU_RW_ATTR(date_of_manufacturing);
1127
1128static IMS_PCU_RO_ATTR(fw_version);
1129static IMS_PCU_RO_ATTR(bl_version);
1130static IMS_PCU_RO_ATTR(reset_reason);
1131
1132static ssize_t ims_pcu_reset_device(struct device *dev,
1133				    struct device_attribute *dattr,
1134				    const char *buf, size_t count)
1135{
1136	static const u8 reset_byte = 1;
1137	struct usb_interface *intf = to_usb_interface(dev);
1138	struct ims_pcu *pcu = usb_get_intfdata(intf);
1139	int value;
1140	int error;
1141
1142	error = kstrtoint(buf, 0, &value);
1143	if (error)
1144		return error;
1145
1146	if (value != 1)
1147		return -EINVAL;
1148
1149	dev_info(pcu->dev, "Attempting to reset device\n");
1150
1151	error = ims_pcu_execute_command(pcu, PCU_RESET, &reset_byte, 1);
1152	if (error) {
1153		dev_info(pcu->dev,
1154			 "Failed to reset device, error: %d\n",
1155			 error);
1156		return error;
1157	}
1158
1159	return count;
1160}
1161
1162static DEVICE_ATTR(reset_device, S_IWUSR, NULL, ims_pcu_reset_device);
1163
1164static ssize_t ims_pcu_update_firmware_store(struct device *dev,
1165					     struct device_attribute *dattr,
1166					     const char *buf, size_t count)
1167{
1168	struct usb_interface *intf = to_usb_interface(dev);
1169	struct ims_pcu *pcu = usb_get_intfdata(intf);
1170	const struct firmware *fw = NULL;
1171	int value;
1172	int error;
1173
1174	error = kstrtoint(buf, 0, &value);
1175	if (error)
1176		return error;
1177
1178	if (value != 1)
1179		return -EINVAL;
1180
1181	error = mutex_lock_interruptible(&pcu->cmd_mutex);
1182	if (error)
1183		return error;
1184
1185	error = request_ihex_firmware(&fw, IMS_PCU_FIRMWARE_NAME, pcu->dev);
1186	if (error) {
1187		dev_err(pcu->dev, "Failed to request firmware %s, error: %d\n",
1188			IMS_PCU_FIRMWARE_NAME, error);
1189		goto out;
1190	}
1191
1192	/*
1193	 * If we are already in bootloader mode we can proceed with
1194	 * flashing the firmware.
1195	 *
1196	 * If we are in application mode, then we need to switch into
1197	 * bootloader mode, which will cause the device to disconnect
1198	 * and reconnect as different device.
1199	 */
1200	if (pcu->bootloader_mode)
1201		error = ims_pcu_handle_firmware_update(pcu, fw);
1202	else
1203		error = ims_pcu_switch_to_bootloader(pcu);
1204
1205	release_firmware(fw);
1206
1207out:
1208	mutex_unlock(&pcu->cmd_mutex);
1209	return error ?: count;
1210}
1211
1212static DEVICE_ATTR(update_firmware, S_IWUSR,
1213		   NULL, ims_pcu_update_firmware_store);
1214
1215static ssize_t
1216ims_pcu_update_firmware_status_show(struct device *dev,
1217				    struct device_attribute *dattr,
1218				    char *buf)
1219{
1220	struct usb_interface *intf = to_usb_interface(dev);
1221	struct ims_pcu *pcu = usb_get_intfdata(intf);
1222
1223	return scnprintf(buf, PAGE_SIZE, "%d\n", pcu->update_firmware_status);
1224}
1225
1226static DEVICE_ATTR(update_firmware_status, S_IRUGO,
1227		   ims_pcu_update_firmware_status_show, NULL);
1228
1229static struct attribute *ims_pcu_attrs[] = {
1230	&ims_pcu_attr_part_number.dattr.attr,
1231	&ims_pcu_attr_serial_number.dattr.attr,
1232	&ims_pcu_attr_date_of_manufacturing.dattr.attr,
1233	&ims_pcu_attr_fw_version.dattr.attr,
1234	&ims_pcu_attr_bl_version.dattr.attr,
1235	&ims_pcu_attr_reset_reason.dattr.attr,
1236	&dev_attr_reset_device.attr,
1237	&dev_attr_update_firmware.attr,
1238	&dev_attr_update_firmware_status.attr,
1239	NULL
1240};
1241
1242static umode_t ims_pcu_is_attr_visible(struct kobject *kobj,
1243				       struct attribute *attr, int n)
1244{
1245	struct device *dev = container_of(kobj, struct device, kobj);
1246	struct usb_interface *intf = to_usb_interface(dev);
1247	struct ims_pcu *pcu = usb_get_intfdata(intf);
1248	umode_t mode = attr->mode;
1249
1250	if (pcu->bootloader_mode) {
1251		if (attr != &dev_attr_update_firmware_status.attr &&
1252		    attr != &dev_attr_update_firmware.attr &&
1253		    attr != &dev_attr_reset_device.attr) {
1254			mode = 0;
1255		}
1256	} else {
1257		if (attr == &dev_attr_update_firmware_status.attr)
1258			mode = 0;
1259	}
1260
1261	return mode;
1262}
1263
1264static struct attribute_group ims_pcu_attr_group = {
1265	.is_visible	= ims_pcu_is_attr_visible,
1266	.attrs		= ims_pcu_attrs,
1267};
1268
1269/* Support for a separate OFN attribute group */
1270
1271#define OFN_REG_RESULT_OFFSET	2
1272
1273static int ims_pcu_read_ofn_config(struct ims_pcu *pcu, u8 addr, u8 *data)
1274{
1275	int error;
1276	s16 result;
1277
1278	error = ims_pcu_execute_command(pcu, OFN_GET_CONFIG,
1279					&addr, sizeof(addr));
1280	if (error)
1281		return error;
1282
1283	result = (s16)get_unaligned_le16(pcu->cmd_buf + OFN_REG_RESULT_OFFSET);
1284	if (result < 0)
1285		return -EIO;
1286
1287	/* We only need LSB */
1288	*data = pcu->cmd_buf[OFN_REG_RESULT_OFFSET];
1289	return 0;
1290}
1291
1292static int ims_pcu_write_ofn_config(struct ims_pcu *pcu, u8 addr, u8 data)
1293{
1294	u8 buffer[] = { addr, data };
1295	int error;
1296	s16 result;
1297
1298	error = ims_pcu_execute_command(pcu, OFN_SET_CONFIG,
1299					&buffer, sizeof(buffer));
1300	if (error)
1301		return error;
1302
1303	result = (s16)get_unaligned_le16(pcu->cmd_buf + OFN_REG_RESULT_OFFSET);
1304	if (result < 0)
1305		return -EIO;
1306
1307	return 0;
1308}
1309
1310static ssize_t ims_pcu_ofn_reg_data_show(struct device *dev,
1311					 struct device_attribute *dattr,
1312					 char *buf)
1313{
1314	struct usb_interface *intf = to_usb_interface(dev);
1315	struct ims_pcu *pcu = usb_get_intfdata(intf);
1316	int error;
1317	u8 data;
1318
1319	mutex_lock(&pcu->cmd_mutex);
1320	error = ims_pcu_read_ofn_config(pcu, pcu->ofn_reg_addr, &data);
1321	mutex_unlock(&pcu->cmd_mutex);
1322
1323	if (error)
1324		return error;
1325
1326	return scnprintf(buf, PAGE_SIZE, "%x\n", data);
1327}
1328
1329static ssize_t ims_pcu_ofn_reg_data_store(struct device *dev,
1330					  struct device_attribute *dattr,
1331					  const char *buf, size_t count)
1332{
1333	struct usb_interface *intf = to_usb_interface(dev);
1334	struct ims_pcu *pcu = usb_get_intfdata(intf);
1335	int error;
1336	u8 value;
1337
1338	error = kstrtou8(buf, 0, &value);
1339	if (error)
1340		return error;
1341
1342	mutex_lock(&pcu->cmd_mutex);
1343	error = ims_pcu_write_ofn_config(pcu, pcu->ofn_reg_addr, value);
1344	mutex_unlock(&pcu->cmd_mutex);
1345
1346	return error ?: count;
1347}
1348
1349static DEVICE_ATTR(reg_data, S_IRUGO | S_IWUSR,
1350		   ims_pcu_ofn_reg_data_show, ims_pcu_ofn_reg_data_store);
1351
1352static ssize_t ims_pcu_ofn_reg_addr_show(struct device *dev,
1353					 struct device_attribute *dattr,
1354					 char *buf)
1355{
1356	struct usb_interface *intf = to_usb_interface(dev);
1357	struct ims_pcu *pcu = usb_get_intfdata(intf);
1358	int error;
1359
1360	mutex_lock(&pcu->cmd_mutex);
1361	error = scnprintf(buf, PAGE_SIZE, "%x\n", pcu->ofn_reg_addr);
1362	mutex_unlock(&pcu->cmd_mutex);
1363
1364	return error;
1365}
1366
1367static ssize_t ims_pcu_ofn_reg_addr_store(struct device *dev,
1368					  struct device_attribute *dattr,
1369					  const char *buf, size_t count)
1370{
1371	struct usb_interface *intf = to_usb_interface(dev);
1372	struct ims_pcu *pcu = usb_get_intfdata(intf);
1373	int error;
1374	u8 value;
1375
1376	error = kstrtou8(buf, 0, &value);
1377	if (error)
1378		return error;
1379
1380	mutex_lock(&pcu->cmd_mutex);
1381	pcu->ofn_reg_addr = value;
1382	mutex_unlock(&pcu->cmd_mutex);
1383
1384	return count;
1385}
1386
1387static DEVICE_ATTR(reg_addr, S_IRUGO | S_IWUSR,
1388		   ims_pcu_ofn_reg_addr_show, ims_pcu_ofn_reg_addr_store);
1389
1390struct ims_pcu_ofn_bit_attribute {
1391	struct device_attribute dattr;
1392	u8 addr;
1393	u8 nr;
1394};
1395
1396static ssize_t ims_pcu_ofn_bit_show(struct device *dev,
1397				    struct device_attribute *dattr,
1398				    char *buf)
1399{
1400	struct usb_interface *intf = to_usb_interface(dev);
1401	struct ims_pcu *pcu = usb_get_intfdata(intf);
1402	struct ims_pcu_ofn_bit_attribute *attr =
1403		container_of(dattr, struct ims_pcu_ofn_bit_attribute, dattr);
1404	int error;
1405	u8 data;
1406
1407	mutex_lock(&pcu->cmd_mutex);
1408	error = ims_pcu_read_ofn_config(pcu, attr->addr, &data);
1409	mutex_unlock(&pcu->cmd_mutex);
1410
1411	if (error)
1412		return error;
1413
1414	return scnprintf(buf, PAGE_SIZE, "%d\n", !!(data & (1 << attr->nr)));
1415}
1416
1417static ssize_t ims_pcu_ofn_bit_store(struct device *dev,
1418				     struct device_attribute *dattr,
1419				     const char *buf, size_t count)
1420{
1421	struct usb_interface *intf = to_usb_interface(dev);
1422	struct ims_pcu *pcu = usb_get_intfdata(intf);
1423	struct ims_pcu_ofn_bit_attribute *attr =
1424		container_of(dattr, struct ims_pcu_ofn_bit_attribute, dattr);
1425	int error;
1426	int value;
1427	u8 data;
1428
1429	error = kstrtoint(buf, 0, &value);
1430	if (error)
1431		return error;
1432
1433	if (value > 1)
1434		return -EINVAL;
1435
1436	mutex_lock(&pcu->cmd_mutex);
1437
1438	error = ims_pcu_read_ofn_config(pcu, attr->addr, &data);
1439	if (!error) {
1440		if (value)
1441			data |= 1U << attr->nr;
1442		else
1443			data &= ~(1U << attr->nr);
1444
1445		error = ims_pcu_write_ofn_config(pcu, attr->addr, data);
1446	}
1447
1448	mutex_unlock(&pcu->cmd_mutex);
1449
1450	return error ?: count;
1451}
1452
1453#define IMS_PCU_OFN_BIT_ATTR(_field, _addr, _nr)			\
1454struct ims_pcu_ofn_bit_attribute ims_pcu_ofn_attr_##_field = {		\
1455	.dattr = __ATTR(_field, S_IWUSR | S_IRUGO,			\
1456			ims_pcu_ofn_bit_show, ims_pcu_ofn_bit_store),	\
1457	.addr = _addr,							\
1458	.nr = _nr,							\
1459}
1460
1461static IMS_PCU_OFN_BIT_ATTR(engine_enable,   0x60, 7);
1462static IMS_PCU_OFN_BIT_ATTR(speed_enable,    0x60, 6);
1463static IMS_PCU_OFN_BIT_ATTR(assert_enable,   0x60, 5);
1464static IMS_PCU_OFN_BIT_ATTR(xyquant_enable,  0x60, 4);
1465static IMS_PCU_OFN_BIT_ATTR(xyscale_enable,  0x60, 1);
1466
1467static IMS_PCU_OFN_BIT_ATTR(scale_x2,        0x63, 6);
1468static IMS_PCU_OFN_BIT_ATTR(scale_y2,        0x63, 7);
1469
1470static struct attribute *ims_pcu_ofn_attrs[] = {
1471	&dev_attr_reg_data.attr,
1472	&dev_attr_reg_addr.attr,
1473	&ims_pcu_ofn_attr_engine_enable.dattr.attr,
1474	&ims_pcu_ofn_attr_speed_enable.dattr.attr,
1475	&ims_pcu_ofn_attr_assert_enable.dattr.attr,
1476	&ims_pcu_ofn_attr_xyquant_enable.dattr.attr,
1477	&ims_pcu_ofn_attr_xyscale_enable.dattr.attr,
1478	&ims_pcu_ofn_attr_scale_x2.dattr.attr,
1479	&ims_pcu_ofn_attr_scale_y2.dattr.attr,
1480	NULL
1481};
1482
1483static struct attribute_group ims_pcu_ofn_attr_group = {
1484	.name	= "ofn",
1485	.attrs	= ims_pcu_ofn_attrs,
1486};
1487
1488static void ims_pcu_irq(struct urb *urb)
1489{
1490	struct ims_pcu *pcu = urb->context;
1491	int retval, status;
1492
1493	status = urb->status;
1494
1495	switch (status) {
1496	case 0:
1497		/* success */
1498		break;
1499	case -ECONNRESET:
1500	case -ENOENT:
1501	case -ESHUTDOWN:
1502		/* this urb is terminated, clean up */
1503		dev_dbg(pcu->dev, "%s - urb shutting down with status: %d\n",
1504			__func__, status);
1505		return;
1506	default:
1507		dev_dbg(pcu->dev, "%s - nonzero urb status received: %d\n",
1508			__func__, status);
1509		goto exit;
1510	}
1511
1512	dev_dbg(pcu->dev, "%s: received %d: %*ph\n", __func__,
1513		urb->actual_length, urb->actual_length, pcu->urb_in_buf);
1514
1515	if (urb == pcu->urb_in)
1516		ims_pcu_process_data(pcu, urb);
1517
1518exit:
1519	retval = usb_submit_urb(urb, GFP_ATOMIC);
1520	if (retval && retval != -ENODEV)
1521		dev_err(pcu->dev, "%s - usb_submit_urb failed with result %d\n",
1522			__func__, retval);
1523}
1524
1525static int ims_pcu_buffers_alloc(struct ims_pcu *pcu)
1526{
1527	int error;
1528
1529	pcu->urb_in_buf = usb_alloc_coherent(pcu->udev, pcu->max_in_size,
1530					     GFP_KERNEL, &pcu->read_dma);
1531	if (!pcu->urb_in_buf) {
1532		dev_err(pcu->dev,
1533			"Failed to allocate memory for read buffer\n");
1534		return -ENOMEM;
1535	}
1536
1537	pcu->urb_in = usb_alloc_urb(0, GFP_KERNEL);
1538	if (!pcu->urb_in) {
1539		dev_err(pcu->dev, "Failed to allocate input URB\n");
1540		error = -ENOMEM;
1541		goto err_free_urb_in_buf;
1542	}
1543
1544	pcu->urb_in->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1545	pcu->urb_in->transfer_dma = pcu->read_dma;
1546
1547	usb_fill_bulk_urb(pcu->urb_in, pcu->udev,
1548			  usb_rcvbulkpipe(pcu->udev,
1549					  pcu->ep_in->bEndpointAddress),
1550			  pcu->urb_in_buf, pcu->max_in_size,
1551			  ims_pcu_irq, pcu);
1552
1553	/*
1554	 * We are using usb_bulk_msg() for sending so there is no point
1555	 * in allocating memory with usb_alloc_coherent().
1556	 */
1557	pcu->urb_out_buf = kmalloc(pcu->max_out_size, GFP_KERNEL);
1558	if (!pcu->urb_out_buf) {
1559		dev_err(pcu->dev, "Failed to allocate memory for write buffer\n");
1560		error = -ENOMEM;
1561		goto err_free_in_urb;
1562	}
1563
1564	pcu->urb_ctrl_buf = usb_alloc_coherent(pcu->udev, pcu->max_ctrl_size,
1565					       GFP_KERNEL, &pcu->ctrl_dma);
1566	if (!pcu->urb_ctrl_buf) {
1567		dev_err(pcu->dev,
1568			"Failed to allocate memory for read buffer\n");
1569		error = -ENOMEM;
1570		goto err_free_urb_out_buf;
1571	}
1572
1573	pcu->urb_ctrl = usb_alloc_urb(0, GFP_KERNEL);
1574	if (!pcu->urb_ctrl) {
1575		dev_err(pcu->dev, "Failed to allocate input URB\n");
1576		error = -ENOMEM;
1577		goto err_free_urb_ctrl_buf;
1578	}
1579
1580	pcu->urb_ctrl->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1581	pcu->urb_ctrl->transfer_dma = pcu->ctrl_dma;
1582
1583	usb_fill_int_urb(pcu->urb_ctrl, pcu->udev,
1584			  usb_rcvintpipe(pcu->udev,
1585					 pcu->ep_ctrl->bEndpointAddress),
1586			  pcu->urb_ctrl_buf, pcu->max_ctrl_size,
1587			  ims_pcu_irq, pcu, pcu->ep_ctrl->bInterval);
1588
1589	return 0;
1590
1591err_free_urb_ctrl_buf:
1592	usb_free_coherent(pcu->udev, pcu->max_ctrl_size,
1593			  pcu->urb_ctrl_buf, pcu->ctrl_dma);
1594err_free_urb_out_buf:
1595	kfree(pcu->urb_out_buf);
1596err_free_in_urb:
1597	usb_free_urb(pcu->urb_in);
1598err_free_urb_in_buf:
1599	usb_free_coherent(pcu->udev, pcu->max_in_size,
1600			  pcu->urb_in_buf, pcu->read_dma);
1601	return error;
1602}
1603
1604static void ims_pcu_buffers_free(struct ims_pcu *pcu)
1605{
1606	usb_kill_urb(pcu->urb_in);
1607	usb_free_urb(pcu->urb_in);
1608
1609	usb_free_coherent(pcu->udev, pcu->max_out_size,
1610			  pcu->urb_in_buf, pcu->read_dma);
1611
1612	kfree(pcu->urb_out_buf);
1613
1614	usb_kill_urb(pcu->urb_ctrl);
1615	usb_free_urb(pcu->urb_ctrl);
1616
1617	usb_free_coherent(pcu->udev, pcu->max_ctrl_size,
1618			  pcu->urb_ctrl_buf, pcu->ctrl_dma);
1619}
1620
1621static const struct usb_cdc_union_desc *
1622ims_pcu_get_cdc_union_desc(struct usb_interface *intf)
1623{
1624	const void *buf = intf->altsetting->extra;
1625	size_t buflen = intf->altsetting->extralen;
1626	struct usb_cdc_union_desc *union_desc;
1627
1628	if (!buf) {
1629		dev_err(&intf->dev, "Missing descriptor data\n");
1630		return NULL;
1631	}
1632
1633	if (!buflen) {
1634		dev_err(&intf->dev, "Zero length descriptor\n");
1635		return NULL;
1636	}
1637
1638	while (buflen > 0) {
1639		union_desc = (struct usb_cdc_union_desc *)buf;
1640
1641		if (union_desc->bDescriptorType == USB_DT_CS_INTERFACE &&
1642		    union_desc->bDescriptorSubType == USB_CDC_UNION_TYPE) {
1643			dev_dbg(&intf->dev, "Found union header\n");
1644			return union_desc;
1645		}
1646
1647		buflen -= union_desc->bLength;
1648		buf += union_desc->bLength;
1649	}
1650
1651	dev_err(&intf->dev, "Missing CDC union descriptor\n");
1652	return NULL;
1653}
1654
1655static int ims_pcu_parse_cdc_data(struct usb_interface *intf, struct ims_pcu *pcu)
1656{
1657	const struct usb_cdc_union_desc *union_desc;
1658	struct usb_host_interface *alt;
1659
1660	union_desc = ims_pcu_get_cdc_union_desc(intf);
1661	if (!union_desc)
1662		return -EINVAL;
1663
1664	pcu->ctrl_intf = usb_ifnum_to_if(pcu->udev,
1665					 union_desc->bMasterInterface0);
1666	if (!pcu->ctrl_intf)
1667		return -EINVAL;
1668
1669	alt = pcu->ctrl_intf->cur_altsetting;
1670	pcu->ep_ctrl = &alt->endpoint[0].desc;
1671	pcu->max_ctrl_size = usb_endpoint_maxp(pcu->ep_ctrl);
1672
1673	pcu->data_intf = usb_ifnum_to_if(pcu->udev,
1674					 union_desc->bSlaveInterface0);
1675	if (!pcu->data_intf)
1676		return -EINVAL;
1677
1678	alt = pcu->data_intf->cur_altsetting;
1679	if (alt->desc.bNumEndpoints != 2) {
1680		dev_err(pcu->dev,
1681			"Incorrect number of endpoints on data interface (%d)\n",
1682			alt->desc.bNumEndpoints);
1683		return -EINVAL;
1684	}
1685
1686	pcu->ep_out = &alt->endpoint[0].desc;
1687	if (!usb_endpoint_is_bulk_out(pcu->ep_out)) {
1688		dev_err(pcu->dev,
1689			"First endpoint on data interface is not BULK OUT\n");
1690		return -EINVAL;
1691	}
1692
1693	pcu->max_out_size = usb_endpoint_maxp(pcu->ep_out);
1694	if (pcu->max_out_size < 8) {
1695		dev_err(pcu->dev,
1696			"Max OUT packet size is too small (%zd)\n",
1697			pcu->max_out_size);
1698		return -EINVAL;
1699	}
1700
1701	pcu->ep_in = &alt->endpoint[1].desc;
1702	if (!usb_endpoint_is_bulk_in(pcu->ep_in)) {
1703		dev_err(pcu->dev,
1704			"Second endpoint on data interface is not BULK IN\n");
1705		return -EINVAL;
1706	}
1707
1708	pcu->max_in_size = usb_endpoint_maxp(pcu->ep_in);
1709	if (pcu->max_in_size < 8) {
1710		dev_err(pcu->dev,
1711			"Max IN packet size is too small (%zd)\n",
1712			pcu->max_in_size);
1713		return -EINVAL;
1714	}
1715
1716	return 0;
1717}
1718
1719static int ims_pcu_start_io(struct ims_pcu *pcu)
1720{
1721	int error;
1722
1723	error = usb_submit_urb(pcu->urb_ctrl, GFP_KERNEL);
1724	if (error) {
1725		dev_err(pcu->dev,
1726			"Failed to start control IO - usb_submit_urb failed with result: %d\n",
1727			error);
1728		return -EIO;
1729	}
1730
1731	error = usb_submit_urb(pcu->urb_in, GFP_KERNEL);
1732	if (error) {
1733		dev_err(pcu->dev,
1734			"Failed to start IO - usb_submit_urb failed with result: %d\n",
1735			error);
1736		usb_kill_urb(pcu->urb_ctrl);
1737		return -EIO;
1738	}
1739
1740	return 0;
1741}
1742
1743static void ims_pcu_stop_io(struct ims_pcu *pcu)
1744{
1745	usb_kill_urb(pcu->urb_in);
1746	usb_kill_urb(pcu->urb_ctrl);
1747}
1748
1749static int ims_pcu_line_setup(struct ims_pcu *pcu)
1750{
1751	struct usb_host_interface *interface = pcu->ctrl_intf->cur_altsetting;
1752	struct usb_cdc_line_coding *line = (void *)pcu->cmd_buf;
1753	int error;
1754
1755	memset(line, 0, sizeof(*line));
1756	line->dwDTERate = cpu_to_le32(57600);
1757	line->bDataBits = 8;
1758
1759	error = usb_control_msg(pcu->udev, usb_sndctrlpipe(pcu->udev, 0),
1760				USB_CDC_REQ_SET_LINE_CODING,
1761				USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1762				0, interface->desc.bInterfaceNumber,
1763				line, sizeof(struct usb_cdc_line_coding),
1764				5000);
1765	if (error < 0) {
1766		dev_err(pcu->dev, "Failed to set line coding, error: %d\n",
1767			error);
1768		return error;
1769	}
1770
1771	error = usb_control_msg(pcu->udev, usb_sndctrlpipe(pcu->udev, 0),
1772				USB_CDC_REQ_SET_CONTROL_LINE_STATE,
1773				USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1774				0x03, interface->desc.bInterfaceNumber,
1775				NULL, 0, 5000);
1776	if (error < 0) {
1777		dev_err(pcu->dev, "Failed to set line state, error: %d\n",
1778			error);
1779		return error;
1780	}
1781
1782	return 0;
1783}
1784
1785static int ims_pcu_get_device_info(struct ims_pcu *pcu)
1786{
1787	int error;
1788
1789	error = ims_pcu_get_info(pcu);
1790	if (error)
1791		return error;
1792
1793	error = ims_pcu_execute_query(pcu, GET_FW_VERSION);
1794	if (error) {
1795		dev_err(pcu->dev,
1796			"GET_FW_VERSION command failed, error: %d\n", error);
1797		return error;
1798	}
1799
1800	snprintf(pcu->fw_version, sizeof(pcu->fw_version),
1801		 "%02d%02d%02d%02d.%c%c",
1802		 pcu->cmd_buf[2], pcu->cmd_buf[3], pcu->cmd_buf[4], pcu->cmd_buf[5],
1803		 pcu->cmd_buf[6], pcu->cmd_buf[7]);
1804
1805	error = ims_pcu_execute_query(pcu, GET_BL_VERSION);
1806	if (error) {
1807		dev_err(pcu->dev,
1808			"GET_BL_VERSION command failed, error: %d\n", error);
1809		return error;
1810	}
1811
1812	snprintf(pcu->bl_version, sizeof(pcu->bl_version),
1813		 "%02d%02d%02d%02d.%c%c",
1814		 pcu->cmd_buf[2], pcu->cmd_buf[3], pcu->cmd_buf[4], pcu->cmd_buf[5],
1815		 pcu->cmd_buf[6], pcu->cmd_buf[7]);
1816
1817	error = ims_pcu_execute_query(pcu, RESET_REASON);
1818	if (error) {
1819		dev_err(pcu->dev,
1820			"RESET_REASON command failed, error: %d\n", error);
1821		return error;
1822	}
1823
1824	snprintf(pcu->reset_reason, sizeof(pcu->reset_reason),
1825		 "%02x", pcu->cmd_buf[IMS_PCU_DATA_OFFSET]);
1826
1827	dev_dbg(pcu->dev,
1828		"P/N: %s, MD: %s, S/N: %s, FW: %s, BL: %s, RR: %s\n",
1829		pcu->part_number,
1830		pcu->date_of_manufacturing,
1831		pcu->serial_number,
1832		pcu->fw_version,
1833		pcu->bl_version,
1834		pcu->reset_reason);
1835
1836	return 0;
1837}
1838
1839static int ims_pcu_identify_type(struct ims_pcu *pcu, u8 *device_id)
1840{
1841	int error;
1842
1843	error = ims_pcu_execute_query(pcu, GET_DEVICE_ID);
1844	if (error) {
1845		dev_err(pcu->dev,
1846			"GET_DEVICE_ID command failed, error: %d\n", error);
1847		return error;
1848	}
1849
1850	*device_id = pcu->cmd_buf[IMS_PCU_DATA_OFFSET];
1851	dev_dbg(pcu->dev, "Detected device ID: %d\n", *device_id);
1852
1853	return 0;
1854}
1855
1856static int ims_pcu_init_application_mode(struct ims_pcu *pcu)
1857{
1858	static atomic_t device_no = ATOMIC_INIT(-1);
1859
1860	const struct ims_pcu_device_info *info;
1861	int error;
1862
1863	error = ims_pcu_get_device_info(pcu);
1864	if (error) {
1865		/* Device does not respond to basic queries, hopeless */
1866		return error;
1867	}
1868
1869	error = ims_pcu_identify_type(pcu, &pcu->device_id);
1870	if (error) {
1871		dev_err(pcu->dev,
1872			"Failed to identify device, error: %d\n", error);
1873		/*
1874		 * Do not signal error, but do not create input nor
1875		 * backlight devices either, let userspace figure this
1876		 * out (flash a new firmware?).
1877		 */
1878		return 0;
1879	}
1880
1881	if (pcu->device_id >= ARRAY_SIZE(ims_pcu_device_info) ||
1882	    !ims_pcu_device_info[pcu->device_id].keymap) {
1883		dev_err(pcu->dev, "Device ID %d is not valid\n", pcu->device_id);
1884		/* Same as above, punt to userspace */
1885		return 0;
1886	}
1887
1888	/* Device appears to be operable, complete initialization */
1889	pcu->device_no = atomic_inc_return(&device_no);
1890
1891	/*
1892	 * PCU-B devices, both GEN_1 and GEN_2 do not have OFN sensor
1893	 */
1894	if (pcu->device_id != IMS_PCU_PCU_B_DEVICE_ID) {
1895		error = sysfs_create_group(&pcu->dev->kobj,
1896					   &ims_pcu_ofn_attr_group);
1897		if (error)
1898			return error;
1899	}
1900
1901	error = ims_pcu_setup_backlight(pcu);
1902	if (error)
1903		return error;
1904
1905	info = &ims_pcu_device_info[pcu->device_id];
1906	error = ims_pcu_setup_buttons(pcu, info->keymap, info->keymap_len);
1907	if (error)
1908		goto err_destroy_backlight;
1909
1910	if (info->has_gamepad) {
1911		error = ims_pcu_setup_gamepad(pcu);
1912		if (error)
1913			goto err_destroy_buttons;
1914	}
1915
1916	pcu->setup_complete = true;
1917
1918	return 0;
1919
1920err_destroy_buttons:
1921	ims_pcu_destroy_buttons(pcu);
1922err_destroy_backlight:
1923	ims_pcu_destroy_backlight(pcu);
1924	return error;
1925}
1926
1927static void ims_pcu_destroy_application_mode(struct ims_pcu *pcu)
1928{
1929	if (pcu->setup_complete) {
1930		pcu->setup_complete = false;
1931		mb(); /* make sure flag setting is not reordered */
1932
1933		if (pcu->gamepad)
1934			ims_pcu_destroy_gamepad(pcu);
1935		ims_pcu_destroy_buttons(pcu);
1936		ims_pcu_destroy_backlight(pcu);
1937
1938		if (pcu->device_id != IMS_PCU_PCU_B_DEVICE_ID)
1939			sysfs_remove_group(&pcu->dev->kobj,
1940					   &ims_pcu_ofn_attr_group);
1941	}
1942}
1943
1944static int ims_pcu_init_bootloader_mode(struct ims_pcu *pcu)
1945{
1946	int error;
1947
1948	error = ims_pcu_execute_bl_command(pcu, QUERY_DEVICE, NULL, 0,
1949					   IMS_PCU_CMD_RESPONSE_TIMEOUT);
1950	if (error) {
1951		dev_err(pcu->dev, "Bootloader does not respond, aborting\n");
1952		return error;
1953	}
1954
1955	pcu->fw_start_addr =
1956		get_unaligned_le32(&pcu->cmd_buf[IMS_PCU_DATA_OFFSET + 11]);
1957	pcu->fw_end_addr =
1958		get_unaligned_le32(&pcu->cmd_buf[IMS_PCU_DATA_OFFSET + 15]);
1959
1960	dev_info(pcu->dev,
1961		 "Device is in bootloader mode (addr 0x%08x-0x%08x), requesting firmware\n",
1962		 pcu->fw_start_addr, pcu->fw_end_addr);
1963
1964	error = request_firmware_nowait(THIS_MODULE, true,
1965					IMS_PCU_FIRMWARE_NAME,
1966					pcu->dev, GFP_KERNEL, pcu,
1967					ims_pcu_process_async_firmware);
1968	if (error) {
1969		/* This error is not fatal, let userspace have another chance */
1970		complete(&pcu->async_firmware_done);
1971	}
1972
1973	return 0;
1974}
1975
1976static void ims_pcu_destroy_bootloader_mode(struct ims_pcu *pcu)
1977{
1978	/* Make sure our initial firmware request has completed */
1979	wait_for_completion(&pcu->async_firmware_done);
1980}
1981
1982#define IMS_PCU_APPLICATION_MODE	0
1983#define IMS_PCU_BOOTLOADER_MODE		1
1984
1985static struct usb_driver ims_pcu_driver;
1986
1987static int ims_pcu_probe(struct usb_interface *intf,
1988			 const struct usb_device_id *id)
1989{
1990	struct usb_device *udev = interface_to_usbdev(intf);
1991	struct ims_pcu *pcu;
1992	int error;
1993
1994	pcu = kzalloc(sizeof(struct ims_pcu), GFP_KERNEL);
1995	if (!pcu)
1996		return -ENOMEM;
1997
1998	pcu->dev = &intf->dev;
1999	pcu->udev = udev;
2000	pcu->bootloader_mode = id->driver_info == IMS_PCU_BOOTLOADER_MODE;
2001	mutex_init(&pcu->cmd_mutex);
2002	init_completion(&pcu->cmd_done);
2003	init_completion(&pcu->async_firmware_done);
2004
2005	error = ims_pcu_parse_cdc_data(intf, pcu);
2006	if (error)
2007		goto err_free_mem;
2008
2009	error = usb_driver_claim_interface(&ims_pcu_driver,
2010					   pcu->data_intf, pcu);
2011	if (error) {
2012		dev_err(&intf->dev,
2013			"Unable to claim corresponding data interface: %d\n",
2014			error);
2015		goto err_free_mem;
2016	}
2017
2018	usb_set_intfdata(pcu->ctrl_intf, pcu);
2019	usb_set_intfdata(pcu->data_intf, pcu);
2020
2021	error = ims_pcu_buffers_alloc(pcu);
2022	if (error)
2023		goto err_unclaim_intf;
2024
2025	error = ims_pcu_start_io(pcu);
2026	if (error)
2027		goto err_free_buffers;
2028
2029	error = ims_pcu_line_setup(pcu);
2030	if (error)
2031		goto err_stop_io;
2032
2033	error = sysfs_create_group(&intf->dev.kobj, &ims_pcu_attr_group);
2034	if (error)
2035		goto err_stop_io;
2036
2037	error = pcu->bootloader_mode ?
2038			ims_pcu_init_bootloader_mode(pcu) :
2039			ims_pcu_init_application_mode(pcu);
2040	if (error)
2041		goto err_remove_sysfs;
2042
2043	return 0;
2044
2045err_remove_sysfs:
2046	sysfs_remove_group(&intf->dev.kobj, &ims_pcu_attr_group);
2047err_stop_io:
2048	ims_pcu_stop_io(pcu);
2049err_free_buffers:
2050	ims_pcu_buffers_free(pcu);
2051err_unclaim_intf:
2052	usb_driver_release_interface(&ims_pcu_driver, pcu->data_intf);
2053err_free_mem:
2054	kfree(pcu);
2055	return error;
2056}
2057
2058static void ims_pcu_disconnect(struct usb_interface *intf)
2059{
2060	struct ims_pcu *pcu = usb_get_intfdata(intf);
2061	struct usb_host_interface *alt = intf->cur_altsetting;
2062
2063	usb_set_intfdata(intf, NULL);
2064
2065	/*
2066	 * See if we are dealing with control or data interface. The cleanup
2067	 * happens when we unbind primary (control) interface.
2068	 */
2069	if (alt->desc.bInterfaceClass != USB_CLASS_COMM)
2070		return;
2071
2072	sysfs_remove_group(&intf->dev.kobj, &ims_pcu_attr_group);
2073
2074	ims_pcu_stop_io(pcu);
2075
2076	if (pcu->bootloader_mode)
2077		ims_pcu_destroy_bootloader_mode(pcu);
2078	else
2079		ims_pcu_destroy_application_mode(pcu);
2080
2081	ims_pcu_buffers_free(pcu);
2082	kfree(pcu);
2083}
2084
2085#ifdef CONFIG_PM
2086static int ims_pcu_suspend(struct usb_interface *intf,
2087			   pm_message_t message)
2088{
2089	struct ims_pcu *pcu = usb_get_intfdata(intf);
2090	struct usb_host_interface *alt = intf->cur_altsetting;
2091
2092	if (alt->desc.bInterfaceClass == USB_CLASS_COMM)
2093		ims_pcu_stop_io(pcu);
2094
2095	return 0;
2096}
2097
2098static int ims_pcu_resume(struct usb_interface *intf)
2099{
2100	struct ims_pcu *pcu = usb_get_intfdata(intf);
2101	struct usb_host_interface *alt = intf->cur_altsetting;
2102	int retval = 0;
2103
2104	if (alt->desc.bInterfaceClass == USB_CLASS_COMM) {
2105		retval = ims_pcu_start_io(pcu);
2106		if (retval == 0)
2107			retval = ims_pcu_line_setup(pcu);
2108	}
2109
2110	return retval;
2111}
2112#endif
2113
2114static const struct usb_device_id ims_pcu_id_table[] = {
2115	{
2116		USB_DEVICE_AND_INTERFACE_INFO(0x04d8, 0x0082,
2117					USB_CLASS_COMM,
2118					USB_CDC_SUBCLASS_ACM,
2119					USB_CDC_ACM_PROTO_AT_V25TER),
2120		.driver_info = IMS_PCU_APPLICATION_MODE,
2121	},
2122	{
2123		USB_DEVICE_AND_INTERFACE_INFO(0x04d8, 0x0083,
2124					USB_CLASS_COMM,
2125					USB_CDC_SUBCLASS_ACM,
2126					USB_CDC_ACM_PROTO_AT_V25TER),
2127		.driver_info = IMS_PCU_BOOTLOADER_MODE,
2128	},
2129	{ }
2130};
2131
2132static struct usb_driver ims_pcu_driver = {
2133	.name			= "ims_pcu",
2134	.id_table		= ims_pcu_id_table,
2135	.probe			= ims_pcu_probe,
2136	.disconnect		= ims_pcu_disconnect,
2137#ifdef CONFIG_PM
2138	.suspend		= ims_pcu_suspend,
2139	.resume			= ims_pcu_resume,
2140	.reset_resume		= ims_pcu_resume,
2141#endif
2142};
2143
2144module_usb_driver(ims_pcu_driver);
2145
2146MODULE_DESCRIPTION("IMS Passenger Control Unit driver");
2147MODULE_AUTHOR("Dmitry Torokhov <dmitry.torokhov@gmail.com>");
2148MODULE_LICENSE("GPL");
2149