xref: /openbmc/linux/drivers/input/misc/ims-pcu.c (revision af9b2ff010f593d81e2f5fb04155e9fc25b9dfd0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Driver for IMS Passenger Control Unit Devices
4  *
5  * Copyright (C) 2013 The IMS Company
6  */
7 
8 #include <linux/completion.h>
9 #include <linux/device.h>
10 #include <linux/firmware.h>
11 #include <linux/ihex.h>
12 #include <linux/input.h>
13 #include <linux/kernel.h>
14 #include <linux/leds.h>
15 #include <linux/module.h>
16 #include <linux/slab.h>
17 #include <linux/types.h>
18 #include <linux/usb/input.h>
19 #include <linux/usb/cdc.h>
20 #include <asm/unaligned.h>
21 
22 #define IMS_PCU_KEYMAP_LEN		32
23 
24 struct ims_pcu_buttons {
25 	struct input_dev *input;
26 	char name[32];
27 	char phys[32];
28 	unsigned short keymap[IMS_PCU_KEYMAP_LEN];
29 };
30 
31 struct ims_pcu_gamepad {
32 	struct input_dev *input;
33 	char name[32];
34 	char phys[32];
35 };
36 
37 struct ims_pcu_backlight {
38 	struct led_classdev cdev;
39 	char name[32];
40 };
41 
42 #define IMS_PCU_PART_NUMBER_LEN		15
43 #define IMS_PCU_SERIAL_NUMBER_LEN	8
44 #define IMS_PCU_DOM_LEN			8
45 #define IMS_PCU_FW_VERSION_LEN		16
46 #define IMS_PCU_BL_VERSION_LEN		16
47 #define IMS_PCU_BL_RESET_REASON_LEN	(2 + 1)
48 
49 #define IMS_PCU_PCU_B_DEVICE_ID		5
50 
51 #define IMS_PCU_BUF_SIZE		128
52 
53 struct ims_pcu {
54 	struct usb_device *udev;
55 	struct device *dev; /* control interface's device, used for logging */
56 
57 	unsigned int device_no;
58 
59 	bool bootloader_mode;
60 
61 	char part_number[IMS_PCU_PART_NUMBER_LEN];
62 	char serial_number[IMS_PCU_SERIAL_NUMBER_LEN];
63 	char date_of_manufacturing[IMS_PCU_DOM_LEN];
64 	char fw_version[IMS_PCU_FW_VERSION_LEN];
65 	char bl_version[IMS_PCU_BL_VERSION_LEN];
66 	char reset_reason[IMS_PCU_BL_RESET_REASON_LEN];
67 	int update_firmware_status;
68 	u8 device_id;
69 
70 	u8 ofn_reg_addr;
71 
72 	struct usb_interface *ctrl_intf;
73 
74 	struct usb_endpoint_descriptor *ep_ctrl;
75 	struct urb *urb_ctrl;
76 	u8 *urb_ctrl_buf;
77 	dma_addr_t ctrl_dma;
78 	size_t max_ctrl_size;
79 
80 	struct usb_interface *data_intf;
81 
82 	struct usb_endpoint_descriptor *ep_in;
83 	struct urb *urb_in;
84 	u8 *urb_in_buf;
85 	dma_addr_t read_dma;
86 	size_t max_in_size;
87 
88 	struct usb_endpoint_descriptor *ep_out;
89 	u8 *urb_out_buf;
90 	size_t max_out_size;
91 
92 	u8 read_buf[IMS_PCU_BUF_SIZE];
93 	u8 read_pos;
94 	u8 check_sum;
95 	bool have_stx;
96 	bool have_dle;
97 
98 	u8 cmd_buf[IMS_PCU_BUF_SIZE];
99 	u8 ack_id;
100 	u8 expected_response;
101 	u8 cmd_buf_len;
102 	struct completion cmd_done;
103 	struct mutex cmd_mutex;
104 
105 	u32 fw_start_addr;
106 	u32 fw_end_addr;
107 	struct completion async_firmware_done;
108 
109 	struct ims_pcu_buttons buttons;
110 	struct ims_pcu_gamepad *gamepad;
111 	struct ims_pcu_backlight backlight;
112 
113 	bool setup_complete; /* Input and LED devices have been created */
114 };
115 
116 
117 /*********************************************************************
118  *             Buttons Input device support                          *
119  *********************************************************************/
120 
121 static const unsigned short ims_pcu_keymap_1[] = {
122 	[1] = KEY_ATTENDANT_OFF,
123 	[2] = KEY_ATTENDANT_ON,
124 	[3] = KEY_LIGHTS_TOGGLE,
125 	[4] = KEY_VOLUMEUP,
126 	[5] = KEY_VOLUMEDOWN,
127 	[6] = KEY_INFO,
128 };
129 
130 static const unsigned short ims_pcu_keymap_2[] = {
131 	[4] = KEY_VOLUMEUP,
132 	[5] = KEY_VOLUMEDOWN,
133 	[6] = KEY_INFO,
134 };
135 
136 static const unsigned short ims_pcu_keymap_3[] = {
137 	[1] = KEY_HOMEPAGE,
138 	[2] = KEY_ATTENDANT_TOGGLE,
139 	[3] = KEY_LIGHTS_TOGGLE,
140 	[4] = KEY_VOLUMEUP,
141 	[5] = KEY_VOLUMEDOWN,
142 	[6] = KEY_DISPLAYTOGGLE,
143 	[18] = KEY_PLAYPAUSE,
144 };
145 
146 static const unsigned short ims_pcu_keymap_4[] = {
147 	[1] = KEY_ATTENDANT_OFF,
148 	[2] = KEY_ATTENDANT_ON,
149 	[3] = KEY_LIGHTS_TOGGLE,
150 	[4] = KEY_VOLUMEUP,
151 	[5] = KEY_VOLUMEDOWN,
152 	[6] = KEY_INFO,
153 	[18] = KEY_PLAYPAUSE,
154 };
155 
156 static const unsigned short ims_pcu_keymap_5[] = {
157 	[1] = KEY_ATTENDANT_OFF,
158 	[2] = KEY_ATTENDANT_ON,
159 	[3] = KEY_LIGHTS_TOGGLE,
160 };
161 
162 struct ims_pcu_device_info {
163 	const unsigned short *keymap;
164 	size_t keymap_len;
165 	bool has_gamepad;
166 };
167 
168 #define IMS_PCU_DEVINFO(_n, _gamepad)				\
169 	[_n] = {						\
170 		.keymap = ims_pcu_keymap_##_n,			\
171 		.keymap_len = ARRAY_SIZE(ims_pcu_keymap_##_n),	\
172 		.has_gamepad = _gamepad,			\
173 	}
174 
175 static const struct ims_pcu_device_info ims_pcu_device_info[] = {
176 	IMS_PCU_DEVINFO(1, true),
177 	IMS_PCU_DEVINFO(2, true),
178 	IMS_PCU_DEVINFO(3, true),
179 	IMS_PCU_DEVINFO(4, true),
180 	IMS_PCU_DEVINFO(5, false),
181 };
182 
ims_pcu_buttons_report(struct ims_pcu * pcu,u32 data)183 static void ims_pcu_buttons_report(struct ims_pcu *pcu, u32 data)
184 {
185 	struct ims_pcu_buttons *buttons = &pcu->buttons;
186 	struct input_dev *input = buttons->input;
187 	int i;
188 
189 	for (i = 0; i < 32; i++) {
190 		unsigned short keycode = buttons->keymap[i];
191 
192 		if (keycode != KEY_RESERVED)
193 			input_report_key(input, keycode, data & (1UL << i));
194 	}
195 
196 	input_sync(input);
197 }
198 
ims_pcu_setup_buttons(struct ims_pcu * pcu,const unsigned short * keymap,size_t keymap_len)199 static int ims_pcu_setup_buttons(struct ims_pcu *pcu,
200 				 const unsigned short *keymap,
201 				 size_t keymap_len)
202 {
203 	struct ims_pcu_buttons *buttons = &pcu->buttons;
204 	struct input_dev *input;
205 	int i;
206 	int error;
207 
208 	input = input_allocate_device();
209 	if (!input) {
210 		dev_err(pcu->dev,
211 			"Not enough memory for input input device\n");
212 		return -ENOMEM;
213 	}
214 
215 	snprintf(buttons->name, sizeof(buttons->name),
216 		 "IMS PCU#%d Button Interface", pcu->device_no);
217 
218 	usb_make_path(pcu->udev, buttons->phys, sizeof(buttons->phys));
219 	strlcat(buttons->phys, "/input0", sizeof(buttons->phys));
220 
221 	memcpy(buttons->keymap, keymap, sizeof(*keymap) * keymap_len);
222 
223 	input->name = buttons->name;
224 	input->phys = buttons->phys;
225 	usb_to_input_id(pcu->udev, &input->id);
226 	input->dev.parent = &pcu->ctrl_intf->dev;
227 
228 	input->keycode = buttons->keymap;
229 	input->keycodemax = ARRAY_SIZE(buttons->keymap);
230 	input->keycodesize = sizeof(buttons->keymap[0]);
231 
232 	__set_bit(EV_KEY, input->evbit);
233 	for (i = 0; i < IMS_PCU_KEYMAP_LEN; i++)
234 		__set_bit(buttons->keymap[i], input->keybit);
235 	__clear_bit(KEY_RESERVED, input->keybit);
236 
237 	error = input_register_device(input);
238 	if (error) {
239 		dev_err(pcu->dev,
240 			"Failed to register buttons input device: %d\n",
241 			error);
242 		input_free_device(input);
243 		return error;
244 	}
245 
246 	buttons->input = input;
247 	return 0;
248 }
249 
ims_pcu_destroy_buttons(struct ims_pcu * pcu)250 static void ims_pcu_destroy_buttons(struct ims_pcu *pcu)
251 {
252 	struct ims_pcu_buttons *buttons = &pcu->buttons;
253 
254 	input_unregister_device(buttons->input);
255 }
256 
257 
258 /*********************************************************************
259  *             Gamepad Input device support                          *
260  *********************************************************************/
261 
ims_pcu_gamepad_report(struct ims_pcu * pcu,u32 data)262 static void ims_pcu_gamepad_report(struct ims_pcu *pcu, u32 data)
263 {
264 	struct ims_pcu_gamepad *gamepad = pcu->gamepad;
265 	struct input_dev *input = gamepad->input;
266 	int x, y;
267 
268 	x = !!(data & (1 << 14)) - !!(data & (1 << 13));
269 	y = !!(data & (1 << 12)) - !!(data & (1 << 11));
270 
271 	input_report_abs(input, ABS_X, x);
272 	input_report_abs(input, ABS_Y, y);
273 
274 	input_report_key(input, BTN_A, data & (1 << 7));
275 	input_report_key(input, BTN_B, data & (1 << 8));
276 	input_report_key(input, BTN_X, data & (1 << 9));
277 	input_report_key(input, BTN_Y, data & (1 << 10));
278 	input_report_key(input, BTN_START, data & (1 << 15));
279 	input_report_key(input, BTN_SELECT, data & (1 << 16));
280 
281 	input_sync(input);
282 }
283 
ims_pcu_setup_gamepad(struct ims_pcu * pcu)284 static int ims_pcu_setup_gamepad(struct ims_pcu *pcu)
285 {
286 	struct ims_pcu_gamepad *gamepad;
287 	struct input_dev *input;
288 	int error;
289 
290 	gamepad = kzalloc(sizeof(struct ims_pcu_gamepad), GFP_KERNEL);
291 	input = input_allocate_device();
292 	if (!gamepad || !input) {
293 		dev_err(pcu->dev,
294 			"Not enough memory for gamepad device\n");
295 		error = -ENOMEM;
296 		goto err_free_mem;
297 	}
298 
299 	gamepad->input = input;
300 
301 	snprintf(gamepad->name, sizeof(gamepad->name),
302 		 "IMS PCU#%d Gamepad Interface", pcu->device_no);
303 
304 	usb_make_path(pcu->udev, gamepad->phys, sizeof(gamepad->phys));
305 	strlcat(gamepad->phys, "/input1", sizeof(gamepad->phys));
306 
307 	input->name = gamepad->name;
308 	input->phys = gamepad->phys;
309 	usb_to_input_id(pcu->udev, &input->id);
310 	input->dev.parent = &pcu->ctrl_intf->dev;
311 
312 	__set_bit(EV_KEY, input->evbit);
313 	__set_bit(BTN_A, input->keybit);
314 	__set_bit(BTN_B, input->keybit);
315 	__set_bit(BTN_X, input->keybit);
316 	__set_bit(BTN_Y, input->keybit);
317 	__set_bit(BTN_START, input->keybit);
318 	__set_bit(BTN_SELECT, input->keybit);
319 
320 	__set_bit(EV_ABS, input->evbit);
321 	input_set_abs_params(input, ABS_X, -1, 1, 0, 0);
322 	input_set_abs_params(input, ABS_Y, -1, 1, 0, 0);
323 
324 	error = input_register_device(input);
325 	if (error) {
326 		dev_err(pcu->dev,
327 			"Failed to register gamepad input device: %d\n",
328 			error);
329 		goto err_free_mem;
330 	}
331 
332 	pcu->gamepad = gamepad;
333 	return 0;
334 
335 err_free_mem:
336 	input_free_device(input);
337 	kfree(gamepad);
338 	return error;
339 }
340 
ims_pcu_destroy_gamepad(struct ims_pcu * pcu)341 static void ims_pcu_destroy_gamepad(struct ims_pcu *pcu)
342 {
343 	struct ims_pcu_gamepad *gamepad = pcu->gamepad;
344 
345 	input_unregister_device(gamepad->input);
346 	kfree(gamepad);
347 }
348 
349 
350 /*********************************************************************
351  *             PCU Communication protocol handling                   *
352  *********************************************************************/
353 
354 #define IMS_PCU_PROTOCOL_STX		0x02
355 #define IMS_PCU_PROTOCOL_ETX		0x03
356 #define IMS_PCU_PROTOCOL_DLE		0x10
357 
358 /* PCU commands */
359 #define IMS_PCU_CMD_STATUS		0xa0
360 #define IMS_PCU_CMD_PCU_RESET		0xa1
361 #define IMS_PCU_CMD_RESET_REASON	0xa2
362 #define IMS_PCU_CMD_SEND_BUTTONS	0xa3
363 #define IMS_PCU_CMD_JUMP_TO_BTLDR	0xa4
364 #define IMS_PCU_CMD_GET_INFO		0xa5
365 #define IMS_PCU_CMD_SET_BRIGHTNESS	0xa6
366 #define IMS_PCU_CMD_EEPROM		0xa7
367 #define IMS_PCU_CMD_GET_FW_VERSION	0xa8
368 #define IMS_PCU_CMD_GET_BL_VERSION	0xa9
369 #define IMS_PCU_CMD_SET_INFO		0xab
370 #define IMS_PCU_CMD_GET_BRIGHTNESS	0xac
371 #define IMS_PCU_CMD_GET_DEVICE_ID	0xae
372 #define IMS_PCU_CMD_SPECIAL_INFO	0xb0
373 #define IMS_PCU_CMD_BOOTLOADER		0xb1	/* Pass data to bootloader */
374 #define IMS_PCU_CMD_OFN_SET_CONFIG	0xb3
375 #define IMS_PCU_CMD_OFN_GET_CONFIG	0xb4
376 
377 /* PCU responses */
378 #define IMS_PCU_RSP_STATUS		0xc0
379 #define IMS_PCU_RSP_PCU_RESET		0	/* Originally 0xc1 */
380 #define IMS_PCU_RSP_RESET_REASON	0xc2
381 #define IMS_PCU_RSP_SEND_BUTTONS	0xc3
382 #define IMS_PCU_RSP_JUMP_TO_BTLDR	0	/* Originally 0xc4 */
383 #define IMS_PCU_RSP_GET_INFO		0xc5
384 #define IMS_PCU_RSP_SET_BRIGHTNESS	0xc6
385 #define IMS_PCU_RSP_EEPROM		0xc7
386 #define IMS_PCU_RSP_GET_FW_VERSION	0xc8
387 #define IMS_PCU_RSP_GET_BL_VERSION	0xc9
388 #define IMS_PCU_RSP_SET_INFO		0xcb
389 #define IMS_PCU_RSP_GET_BRIGHTNESS	0xcc
390 #define IMS_PCU_RSP_CMD_INVALID		0xcd
391 #define IMS_PCU_RSP_GET_DEVICE_ID	0xce
392 #define IMS_PCU_RSP_SPECIAL_INFO	0xd0
393 #define IMS_PCU_RSP_BOOTLOADER		0xd1	/* Bootloader response */
394 #define IMS_PCU_RSP_OFN_SET_CONFIG	0xd2
395 #define IMS_PCU_RSP_OFN_GET_CONFIG	0xd3
396 
397 
398 #define IMS_PCU_RSP_EVNT_BUTTONS	0xe0	/* Unsolicited, button state */
399 #define IMS_PCU_GAMEPAD_MASK		0x0001ff80UL	/* Bits 7 through 16 */
400 
401 
402 #define IMS_PCU_MIN_PACKET_LEN		3
403 #define IMS_PCU_DATA_OFFSET		2
404 
405 #define IMS_PCU_CMD_WRITE_TIMEOUT	100 /* msec */
406 #define IMS_PCU_CMD_RESPONSE_TIMEOUT	500 /* msec */
407 
ims_pcu_report_events(struct ims_pcu * pcu)408 static void ims_pcu_report_events(struct ims_pcu *pcu)
409 {
410 	u32 data = get_unaligned_be32(&pcu->read_buf[3]);
411 
412 	ims_pcu_buttons_report(pcu, data & ~IMS_PCU_GAMEPAD_MASK);
413 	if (pcu->gamepad)
414 		ims_pcu_gamepad_report(pcu, data);
415 }
416 
ims_pcu_handle_response(struct ims_pcu * pcu)417 static void ims_pcu_handle_response(struct ims_pcu *pcu)
418 {
419 	switch (pcu->read_buf[0]) {
420 	case IMS_PCU_RSP_EVNT_BUTTONS:
421 		if (likely(pcu->setup_complete))
422 			ims_pcu_report_events(pcu);
423 		break;
424 
425 	default:
426 		/*
427 		 * See if we got command completion.
428 		 * If both the sequence and response code match save
429 		 * the data and signal completion.
430 		 */
431 		if (pcu->read_buf[0] == pcu->expected_response &&
432 		    pcu->read_buf[1] == pcu->ack_id - 1) {
433 
434 			memcpy(pcu->cmd_buf, pcu->read_buf, pcu->read_pos);
435 			pcu->cmd_buf_len = pcu->read_pos;
436 			complete(&pcu->cmd_done);
437 		}
438 		break;
439 	}
440 }
441 
ims_pcu_process_data(struct ims_pcu * pcu,struct urb * urb)442 static void ims_pcu_process_data(struct ims_pcu *pcu, struct urb *urb)
443 {
444 	int i;
445 
446 	for (i = 0; i < urb->actual_length; i++) {
447 		u8 data = pcu->urb_in_buf[i];
448 
449 		/* Skip everything until we get Start Xmit */
450 		if (!pcu->have_stx && data != IMS_PCU_PROTOCOL_STX)
451 			continue;
452 
453 		if (pcu->have_dle) {
454 			pcu->have_dle = false;
455 			pcu->read_buf[pcu->read_pos++] = data;
456 			pcu->check_sum += data;
457 			continue;
458 		}
459 
460 		switch (data) {
461 		case IMS_PCU_PROTOCOL_STX:
462 			if (pcu->have_stx)
463 				dev_warn(pcu->dev,
464 					 "Unexpected STX at byte %d, discarding old data\n",
465 					 pcu->read_pos);
466 			pcu->have_stx = true;
467 			pcu->have_dle = false;
468 			pcu->read_pos = 0;
469 			pcu->check_sum = 0;
470 			break;
471 
472 		case IMS_PCU_PROTOCOL_DLE:
473 			pcu->have_dle = true;
474 			break;
475 
476 		case IMS_PCU_PROTOCOL_ETX:
477 			if (pcu->read_pos < IMS_PCU_MIN_PACKET_LEN) {
478 				dev_warn(pcu->dev,
479 					 "Short packet received (%d bytes), ignoring\n",
480 					 pcu->read_pos);
481 			} else if (pcu->check_sum != 0) {
482 				dev_warn(pcu->dev,
483 					 "Invalid checksum in packet (%d bytes), ignoring\n",
484 					 pcu->read_pos);
485 			} else {
486 				ims_pcu_handle_response(pcu);
487 			}
488 
489 			pcu->have_stx = false;
490 			pcu->have_dle = false;
491 			pcu->read_pos = 0;
492 			break;
493 
494 		default:
495 			pcu->read_buf[pcu->read_pos++] = data;
496 			pcu->check_sum += data;
497 			break;
498 		}
499 	}
500 }
501 
ims_pcu_byte_needs_escape(u8 byte)502 static bool ims_pcu_byte_needs_escape(u8 byte)
503 {
504 	return byte == IMS_PCU_PROTOCOL_STX ||
505 	       byte == IMS_PCU_PROTOCOL_ETX ||
506 	       byte == IMS_PCU_PROTOCOL_DLE;
507 }
508 
ims_pcu_send_cmd_chunk(struct ims_pcu * pcu,u8 command,int chunk,int len)509 static int ims_pcu_send_cmd_chunk(struct ims_pcu *pcu,
510 				  u8 command, int chunk, int len)
511 {
512 	int error;
513 
514 	error = usb_bulk_msg(pcu->udev,
515 			     usb_sndbulkpipe(pcu->udev,
516 					     pcu->ep_out->bEndpointAddress),
517 			     pcu->urb_out_buf, len,
518 			     NULL, IMS_PCU_CMD_WRITE_TIMEOUT);
519 	if (error < 0) {
520 		dev_dbg(pcu->dev,
521 			"Sending 0x%02x command failed at chunk %d: %d\n",
522 			command, chunk, error);
523 		return error;
524 	}
525 
526 	return 0;
527 }
528 
ims_pcu_send_command(struct ims_pcu * pcu,u8 command,const u8 * data,int len)529 static int ims_pcu_send_command(struct ims_pcu *pcu,
530 				u8 command, const u8 *data, int len)
531 {
532 	int count = 0;
533 	int chunk = 0;
534 	int delta;
535 	int i;
536 	int error;
537 	u8 csum = 0;
538 	u8 ack_id;
539 
540 	pcu->urb_out_buf[count++] = IMS_PCU_PROTOCOL_STX;
541 
542 	/* We know the command need not be escaped */
543 	pcu->urb_out_buf[count++] = command;
544 	csum += command;
545 
546 	ack_id = pcu->ack_id++;
547 	if (ack_id == 0xff)
548 		ack_id = pcu->ack_id++;
549 
550 	if (ims_pcu_byte_needs_escape(ack_id))
551 		pcu->urb_out_buf[count++] = IMS_PCU_PROTOCOL_DLE;
552 
553 	pcu->urb_out_buf[count++] = ack_id;
554 	csum += ack_id;
555 
556 	for (i = 0; i < len; i++) {
557 
558 		delta = ims_pcu_byte_needs_escape(data[i]) ? 2 : 1;
559 		if (count + delta >= pcu->max_out_size) {
560 			error = ims_pcu_send_cmd_chunk(pcu, command,
561 						       ++chunk, count);
562 			if (error)
563 				return error;
564 
565 			count = 0;
566 		}
567 
568 		if (delta == 2)
569 			pcu->urb_out_buf[count++] = IMS_PCU_PROTOCOL_DLE;
570 
571 		pcu->urb_out_buf[count++] = data[i];
572 		csum += data[i];
573 	}
574 
575 	csum = 1 + ~csum;
576 
577 	delta = ims_pcu_byte_needs_escape(csum) ? 3 : 2;
578 	if (count + delta >= pcu->max_out_size) {
579 		error = ims_pcu_send_cmd_chunk(pcu, command, ++chunk, count);
580 		if (error)
581 			return error;
582 
583 		count = 0;
584 	}
585 
586 	if (delta == 3)
587 		pcu->urb_out_buf[count++] = IMS_PCU_PROTOCOL_DLE;
588 
589 	pcu->urb_out_buf[count++] = csum;
590 	pcu->urb_out_buf[count++] = IMS_PCU_PROTOCOL_ETX;
591 
592 	return ims_pcu_send_cmd_chunk(pcu, command, ++chunk, count);
593 }
594 
__ims_pcu_execute_command(struct ims_pcu * pcu,u8 command,const void * data,size_t len,u8 expected_response,int response_time)595 static int __ims_pcu_execute_command(struct ims_pcu *pcu,
596 				     u8 command, const void *data, size_t len,
597 				     u8 expected_response, int response_time)
598 {
599 	int error;
600 
601 	pcu->expected_response = expected_response;
602 	init_completion(&pcu->cmd_done);
603 
604 	error = ims_pcu_send_command(pcu, command, data, len);
605 	if (error)
606 		return error;
607 
608 	if (expected_response &&
609 	    !wait_for_completion_timeout(&pcu->cmd_done,
610 					 msecs_to_jiffies(response_time))) {
611 		dev_dbg(pcu->dev, "Command 0x%02x timed out\n", command);
612 		return -ETIMEDOUT;
613 	}
614 
615 	return 0;
616 }
617 
618 #define ims_pcu_execute_command(pcu, code, data, len)			\
619 	__ims_pcu_execute_command(pcu,					\
620 				  IMS_PCU_CMD_##code, data, len,	\
621 				  IMS_PCU_RSP_##code,			\
622 				  IMS_PCU_CMD_RESPONSE_TIMEOUT)
623 
624 #define ims_pcu_execute_query(pcu, code)				\
625 	ims_pcu_execute_command(pcu, code, NULL, 0)
626 
627 /* Bootloader commands */
628 #define IMS_PCU_BL_CMD_QUERY_DEVICE	0xa1
629 #define IMS_PCU_BL_CMD_UNLOCK_CONFIG	0xa2
630 #define IMS_PCU_BL_CMD_ERASE_APP	0xa3
631 #define IMS_PCU_BL_CMD_PROGRAM_DEVICE	0xa4
632 #define IMS_PCU_BL_CMD_PROGRAM_COMPLETE	0xa5
633 #define IMS_PCU_BL_CMD_READ_APP		0xa6
634 #define IMS_PCU_BL_CMD_RESET_DEVICE	0xa7
635 #define IMS_PCU_BL_CMD_LAUNCH_APP	0xa8
636 
637 /* Bootloader commands */
638 #define IMS_PCU_BL_RSP_QUERY_DEVICE	0xc1
639 #define IMS_PCU_BL_RSP_UNLOCK_CONFIG	0xc2
640 #define IMS_PCU_BL_RSP_ERASE_APP	0xc3
641 #define IMS_PCU_BL_RSP_PROGRAM_DEVICE	0xc4
642 #define IMS_PCU_BL_RSP_PROGRAM_COMPLETE	0xc5
643 #define IMS_PCU_BL_RSP_READ_APP		0xc6
644 #define IMS_PCU_BL_RSP_RESET_DEVICE	0	/* originally 0xa7 */
645 #define IMS_PCU_BL_RSP_LAUNCH_APP	0	/* originally 0xa8 */
646 
647 #define IMS_PCU_BL_DATA_OFFSET		3
648 
__ims_pcu_execute_bl_command(struct ims_pcu * pcu,u8 command,const void * data,size_t len,u8 expected_response,int response_time)649 static int __ims_pcu_execute_bl_command(struct ims_pcu *pcu,
650 					u8 command, const void *data, size_t len,
651 					u8 expected_response, int response_time)
652 {
653 	int error;
654 
655 	pcu->cmd_buf[0] = command;
656 	if (data)
657 		memcpy(&pcu->cmd_buf[1], data, len);
658 
659 	error = __ims_pcu_execute_command(pcu,
660 				IMS_PCU_CMD_BOOTLOADER, pcu->cmd_buf, len + 1,
661 				expected_response ? IMS_PCU_RSP_BOOTLOADER : 0,
662 				response_time);
663 	if (error) {
664 		dev_err(pcu->dev,
665 			"Failure when sending 0x%02x command to bootloader, error: %d\n",
666 			pcu->cmd_buf[0], error);
667 		return error;
668 	}
669 
670 	if (expected_response && pcu->cmd_buf[2] != expected_response) {
671 		dev_err(pcu->dev,
672 			"Unexpected response from bootloader: 0x%02x, wanted 0x%02x\n",
673 			pcu->cmd_buf[2], expected_response);
674 		return -EINVAL;
675 	}
676 
677 	return 0;
678 }
679 
680 #define ims_pcu_execute_bl_command(pcu, code, data, len, timeout)	\
681 	__ims_pcu_execute_bl_command(pcu,				\
682 				     IMS_PCU_BL_CMD_##code, data, len,	\
683 				     IMS_PCU_BL_RSP_##code, timeout)	\
684 
685 #define IMS_PCU_INFO_PART_OFFSET	2
686 #define IMS_PCU_INFO_DOM_OFFSET		17
687 #define IMS_PCU_INFO_SERIAL_OFFSET	25
688 
689 #define IMS_PCU_SET_INFO_SIZE		31
690 
ims_pcu_get_info(struct ims_pcu * pcu)691 static int ims_pcu_get_info(struct ims_pcu *pcu)
692 {
693 	int error;
694 
695 	error = ims_pcu_execute_query(pcu, GET_INFO);
696 	if (error) {
697 		dev_err(pcu->dev,
698 			"GET_INFO command failed, error: %d\n", error);
699 		return error;
700 	}
701 
702 	memcpy(pcu->part_number,
703 	       &pcu->cmd_buf[IMS_PCU_INFO_PART_OFFSET],
704 	       sizeof(pcu->part_number));
705 	memcpy(pcu->date_of_manufacturing,
706 	       &pcu->cmd_buf[IMS_PCU_INFO_DOM_OFFSET],
707 	       sizeof(pcu->date_of_manufacturing));
708 	memcpy(pcu->serial_number,
709 	       &pcu->cmd_buf[IMS_PCU_INFO_SERIAL_OFFSET],
710 	       sizeof(pcu->serial_number));
711 
712 	return 0;
713 }
714 
ims_pcu_set_info(struct ims_pcu * pcu)715 static int ims_pcu_set_info(struct ims_pcu *pcu)
716 {
717 	int error;
718 
719 	memcpy(&pcu->cmd_buf[IMS_PCU_INFO_PART_OFFSET],
720 	       pcu->part_number, sizeof(pcu->part_number));
721 	memcpy(&pcu->cmd_buf[IMS_PCU_INFO_DOM_OFFSET],
722 	       pcu->date_of_manufacturing, sizeof(pcu->date_of_manufacturing));
723 	memcpy(&pcu->cmd_buf[IMS_PCU_INFO_SERIAL_OFFSET],
724 	       pcu->serial_number, sizeof(pcu->serial_number));
725 
726 	error = ims_pcu_execute_command(pcu, SET_INFO,
727 					&pcu->cmd_buf[IMS_PCU_DATA_OFFSET],
728 					IMS_PCU_SET_INFO_SIZE);
729 	if (error) {
730 		dev_err(pcu->dev,
731 			"Failed to update device information, error: %d\n",
732 			error);
733 		return error;
734 	}
735 
736 	return 0;
737 }
738 
ims_pcu_switch_to_bootloader(struct ims_pcu * pcu)739 static int ims_pcu_switch_to_bootloader(struct ims_pcu *pcu)
740 {
741 	int error;
742 
743 	/* Execute jump to the bootoloader */
744 	error = ims_pcu_execute_command(pcu, JUMP_TO_BTLDR, NULL, 0);
745 	if (error) {
746 		dev_err(pcu->dev,
747 			"Failure when sending JUMP TO BOOTLOADER command, error: %d\n",
748 			error);
749 		return error;
750 	}
751 
752 	return 0;
753 }
754 
755 /*********************************************************************
756  *             Firmware Update handling                              *
757  *********************************************************************/
758 
759 #define IMS_PCU_FIRMWARE_NAME	"imspcu.fw"
760 
761 struct ims_pcu_flash_fmt {
762 	__le32 addr;
763 	u8 len;
764 	u8 data[];
765 };
766 
ims_pcu_count_fw_records(const struct firmware * fw)767 static unsigned int ims_pcu_count_fw_records(const struct firmware *fw)
768 {
769 	const struct ihex_binrec *rec = (const struct ihex_binrec *)fw->data;
770 	unsigned int count = 0;
771 
772 	while (rec) {
773 		count++;
774 		rec = ihex_next_binrec(rec);
775 	}
776 
777 	return count;
778 }
779 
ims_pcu_verify_block(struct ims_pcu * pcu,u32 addr,u8 len,const u8 * data)780 static int ims_pcu_verify_block(struct ims_pcu *pcu,
781 				u32 addr, u8 len, const u8 *data)
782 {
783 	struct ims_pcu_flash_fmt *fragment;
784 	int error;
785 
786 	fragment = (void *)&pcu->cmd_buf[1];
787 	put_unaligned_le32(addr, &fragment->addr);
788 	fragment->len = len;
789 
790 	error = ims_pcu_execute_bl_command(pcu, READ_APP, NULL, 5,
791 					IMS_PCU_CMD_RESPONSE_TIMEOUT);
792 	if (error) {
793 		dev_err(pcu->dev,
794 			"Failed to retrieve block at 0x%08x, len %d, error: %d\n",
795 			addr, len, error);
796 		return error;
797 	}
798 
799 	fragment = (void *)&pcu->cmd_buf[IMS_PCU_BL_DATA_OFFSET];
800 	if (get_unaligned_le32(&fragment->addr) != addr ||
801 	    fragment->len != len) {
802 		dev_err(pcu->dev,
803 			"Wrong block when retrieving 0x%08x (0x%08x), len %d (%d)\n",
804 			addr, get_unaligned_le32(&fragment->addr),
805 			len, fragment->len);
806 		return -EINVAL;
807 	}
808 
809 	if (memcmp(fragment->data, data, len)) {
810 		dev_err(pcu->dev,
811 			"Mismatch in block at 0x%08x, len %d\n",
812 			addr, len);
813 		return -EINVAL;
814 	}
815 
816 	return 0;
817 }
818 
ims_pcu_flash_firmware(struct ims_pcu * pcu,const struct firmware * fw,unsigned int n_fw_records)819 static int ims_pcu_flash_firmware(struct ims_pcu *pcu,
820 				  const struct firmware *fw,
821 				  unsigned int n_fw_records)
822 {
823 	const struct ihex_binrec *rec = (const struct ihex_binrec *)fw->data;
824 	struct ims_pcu_flash_fmt *fragment;
825 	unsigned int count = 0;
826 	u32 addr;
827 	u8 len;
828 	int error;
829 
830 	error = ims_pcu_execute_bl_command(pcu, ERASE_APP, NULL, 0, 2000);
831 	if (error) {
832 		dev_err(pcu->dev,
833 			"Failed to erase application image, error: %d\n",
834 			error);
835 		return error;
836 	}
837 
838 	while (rec) {
839 		/*
840 		 * The firmware format is messed up for some reason.
841 		 * The address twice that of what is needed for some
842 		 * reason and we end up overwriting half of the data
843 		 * with the next record.
844 		 */
845 		addr = be32_to_cpu(rec->addr) / 2;
846 		len = be16_to_cpu(rec->len);
847 
848 		if (len > sizeof(pcu->cmd_buf) - 1 - sizeof(*fragment)) {
849 			dev_err(pcu->dev,
850 				"Invalid record length in firmware: %d\n", len);
851 			return -EINVAL;
852 		}
853 
854 		fragment = (void *)&pcu->cmd_buf[1];
855 		put_unaligned_le32(addr, &fragment->addr);
856 		fragment->len = len;
857 		memcpy(fragment->data, rec->data, len);
858 
859 		error = ims_pcu_execute_bl_command(pcu, PROGRAM_DEVICE,
860 						NULL, len + 5,
861 						IMS_PCU_CMD_RESPONSE_TIMEOUT);
862 		if (error) {
863 			dev_err(pcu->dev,
864 				"Failed to write block at 0x%08x, len %d, error: %d\n",
865 				addr, len, error);
866 			return error;
867 		}
868 
869 		if (addr >= pcu->fw_start_addr && addr < pcu->fw_end_addr) {
870 			error = ims_pcu_verify_block(pcu, addr, len, rec->data);
871 			if (error)
872 				return error;
873 		}
874 
875 		count++;
876 		pcu->update_firmware_status = (count * 100) / n_fw_records;
877 
878 		rec = ihex_next_binrec(rec);
879 	}
880 
881 	error = ims_pcu_execute_bl_command(pcu, PROGRAM_COMPLETE,
882 					    NULL, 0, 2000);
883 	if (error)
884 		dev_err(pcu->dev,
885 			"Failed to send PROGRAM_COMPLETE, error: %d\n",
886 			error);
887 
888 	return 0;
889 }
890 
ims_pcu_handle_firmware_update(struct ims_pcu * pcu,const struct firmware * fw)891 static int ims_pcu_handle_firmware_update(struct ims_pcu *pcu,
892 					  const struct firmware *fw)
893 {
894 	unsigned int n_fw_records;
895 	int retval;
896 
897 	dev_info(pcu->dev, "Updating firmware %s, size: %zu\n",
898 		 IMS_PCU_FIRMWARE_NAME, fw->size);
899 
900 	n_fw_records = ims_pcu_count_fw_records(fw);
901 
902 	retval = ims_pcu_flash_firmware(pcu, fw, n_fw_records);
903 	if (retval)
904 		goto out;
905 
906 	retval = ims_pcu_execute_bl_command(pcu, LAUNCH_APP, NULL, 0, 0);
907 	if (retval)
908 		dev_err(pcu->dev,
909 			"Failed to start application image, error: %d\n",
910 			retval);
911 
912 out:
913 	pcu->update_firmware_status = retval;
914 	sysfs_notify(&pcu->dev->kobj, NULL, "update_firmware_status");
915 	return retval;
916 }
917 
ims_pcu_process_async_firmware(const struct firmware * fw,void * context)918 static void ims_pcu_process_async_firmware(const struct firmware *fw,
919 					   void *context)
920 {
921 	struct ims_pcu *pcu = context;
922 	int error;
923 
924 	if (!fw) {
925 		dev_err(pcu->dev, "Failed to get firmware %s\n",
926 			IMS_PCU_FIRMWARE_NAME);
927 		goto out;
928 	}
929 
930 	error = ihex_validate_fw(fw);
931 	if (error) {
932 		dev_err(pcu->dev, "Firmware %s is invalid\n",
933 			IMS_PCU_FIRMWARE_NAME);
934 		goto out;
935 	}
936 
937 	mutex_lock(&pcu->cmd_mutex);
938 	ims_pcu_handle_firmware_update(pcu, fw);
939 	mutex_unlock(&pcu->cmd_mutex);
940 
941 	release_firmware(fw);
942 
943 out:
944 	complete(&pcu->async_firmware_done);
945 }
946 
947 /*********************************************************************
948  *             Backlight LED device support                          *
949  *********************************************************************/
950 
951 #define IMS_PCU_MAX_BRIGHTNESS		31998
952 
ims_pcu_backlight_set_brightness(struct led_classdev * cdev,enum led_brightness value)953 static int ims_pcu_backlight_set_brightness(struct led_classdev *cdev,
954 					    enum led_brightness value)
955 {
956 	struct ims_pcu_backlight *backlight =
957 			container_of(cdev, struct ims_pcu_backlight, cdev);
958 	struct ims_pcu *pcu =
959 			container_of(backlight, struct ims_pcu, backlight);
960 	__le16 br_val = cpu_to_le16(value);
961 	int error;
962 
963 	mutex_lock(&pcu->cmd_mutex);
964 
965 	error = ims_pcu_execute_command(pcu, SET_BRIGHTNESS,
966 					&br_val, sizeof(br_val));
967 	if (error && error != -ENODEV)
968 		dev_warn(pcu->dev,
969 			 "Failed to set desired brightness %u, error: %d\n",
970 			 value, error);
971 
972 	mutex_unlock(&pcu->cmd_mutex);
973 
974 	return error;
975 }
976 
977 static enum led_brightness
ims_pcu_backlight_get_brightness(struct led_classdev * cdev)978 ims_pcu_backlight_get_brightness(struct led_classdev *cdev)
979 {
980 	struct ims_pcu_backlight *backlight =
981 			container_of(cdev, struct ims_pcu_backlight, cdev);
982 	struct ims_pcu *pcu =
983 			container_of(backlight, struct ims_pcu, backlight);
984 	int brightness;
985 	int error;
986 
987 	mutex_lock(&pcu->cmd_mutex);
988 
989 	error = ims_pcu_execute_query(pcu, GET_BRIGHTNESS);
990 	if (error) {
991 		dev_warn(pcu->dev,
992 			 "Failed to get current brightness, error: %d\n",
993 			 error);
994 		/* Assume the LED is OFF */
995 		brightness = LED_OFF;
996 	} else {
997 		brightness =
998 			get_unaligned_le16(&pcu->cmd_buf[IMS_PCU_DATA_OFFSET]);
999 	}
1000 
1001 	mutex_unlock(&pcu->cmd_mutex);
1002 
1003 	return brightness;
1004 }
1005 
ims_pcu_setup_backlight(struct ims_pcu * pcu)1006 static int ims_pcu_setup_backlight(struct ims_pcu *pcu)
1007 {
1008 	struct ims_pcu_backlight *backlight = &pcu->backlight;
1009 	int error;
1010 
1011 	snprintf(backlight->name, sizeof(backlight->name),
1012 		 "pcu%d::kbd_backlight", pcu->device_no);
1013 
1014 	backlight->cdev.name = backlight->name;
1015 	backlight->cdev.max_brightness = IMS_PCU_MAX_BRIGHTNESS;
1016 	backlight->cdev.brightness_get = ims_pcu_backlight_get_brightness;
1017 	backlight->cdev.brightness_set_blocking =
1018 					 ims_pcu_backlight_set_brightness;
1019 
1020 	error = led_classdev_register(pcu->dev, &backlight->cdev);
1021 	if (error) {
1022 		dev_err(pcu->dev,
1023 			"Failed to register backlight LED device, error: %d\n",
1024 			error);
1025 		return error;
1026 	}
1027 
1028 	return 0;
1029 }
1030 
ims_pcu_destroy_backlight(struct ims_pcu * pcu)1031 static void ims_pcu_destroy_backlight(struct ims_pcu *pcu)
1032 {
1033 	struct ims_pcu_backlight *backlight = &pcu->backlight;
1034 
1035 	led_classdev_unregister(&backlight->cdev);
1036 }
1037 
1038 
1039 /*********************************************************************
1040  *             Sysfs attributes handling                             *
1041  *********************************************************************/
1042 
1043 struct ims_pcu_attribute {
1044 	struct device_attribute dattr;
1045 	size_t field_offset;
1046 	int field_length;
1047 };
1048 
ims_pcu_attribute_show(struct device * dev,struct device_attribute * dattr,char * buf)1049 static ssize_t ims_pcu_attribute_show(struct device *dev,
1050 				      struct device_attribute *dattr,
1051 				      char *buf)
1052 {
1053 	struct usb_interface *intf = to_usb_interface(dev);
1054 	struct ims_pcu *pcu = usb_get_intfdata(intf);
1055 	struct ims_pcu_attribute *attr =
1056 			container_of(dattr, struct ims_pcu_attribute, dattr);
1057 	char *field = (char *)pcu + attr->field_offset;
1058 
1059 	return scnprintf(buf, PAGE_SIZE, "%.*s\n", attr->field_length, field);
1060 }
1061 
ims_pcu_attribute_store(struct device * dev,struct device_attribute * dattr,const char * buf,size_t count)1062 static ssize_t ims_pcu_attribute_store(struct device *dev,
1063 				       struct device_attribute *dattr,
1064 				       const char *buf, size_t count)
1065 {
1066 
1067 	struct usb_interface *intf = to_usb_interface(dev);
1068 	struct ims_pcu *pcu = usb_get_intfdata(intf);
1069 	struct ims_pcu_attribute *attr =
1070 			container_of(dattr, struct ims_pcu_attribute, dattr);
1071 	char *field = (char *)pcu + attr->field_offset;
1072 	size_t data_len;
1073 	int error;
1074 
1075 	if (count > attr->field_length)
1076 		return -EINVAL;
1077 
1078 	data_len = strnlen(buf, attr->field_length);
1079 	if (data_len > attr->field_length)
1080 		return -EINVAL;
1081 
1082 	error = mutex_lock_interruptible(&pcu->cmd_mutex);
1083 	if (error)
1084 		return error;
1085 
1086 	memset(field, 0, attr->field_length);
1087 	memcpy(field, buf, data_len);
1088 
1089 	error = ims_pcu_set_info(pcu);
1090 
1091 	/*
1092 	 * Even if update failed, let's fetch the info again as we just
1093 	 * clobbered one of the fields.
1094 	 */
1095 	ims_pcu_get_info(pcu);
1096 
1097 	mutex_unlock(&pcu->cmd_mutex);
1098 
1099 	return error < 0 ? error : count;
1100 }
1101 
1102 #define IMS_PCU_ATTR(_field, _mode)					\
1103 struct ims_pcu_attribute ims_pcu_attr_##_field = {			\
1104 	.dattr = __ATTR(_field, _mode,					\
1105 			ims_pcu_attribute_show,				\
1106 			ims_pcu_attribute_store),			\
1107 	.field_offset = offsetof(struct ims_pcu, _field),		\
1108 	.field_length = sizeof(((struct ims_pcu *)NULL)->_field),	\
1109 }
1110 
1111 #define IMS_PCU_RO_ATTR(_field)						\
1112 		IMS_PCU_ATTR(_field, S_IRUGO)
1113 #define IMS_PCU_RW_ATTR(_field)						\
1114 		IMS_PCU_ATTR(_field, S_IRUGO | S_IWUSR)
1115 
1116 static IMS_PCU_RW_ATTR(part_number);
1117 static IMS_PCU_RW_ATTR(serial_number);
1118 static IMS_PCU_RW_ATTR(date_of_manufacturing);
1119 
1120 static IMS_PCU_RO_ATTR(fw_version);
1121 static IMS_PCU_RO_ATTR(bl_version);
1122 static IMS_PCU_RO_ATTR(reset_reason);
1123 
ims_pcu_reset_device(struct device * dev,struct device_attribute * dattr,const char * buf,size_t count)1124 static ssize_t ims_pcu_reset_device(struct device *dev,
1125 				    struct device_attribute *dattr,
1126 				    const char *buf, size_t count)
1127 {
1128 	static const u8 reset_byte = 1;
1129 	struct usb_interface *intf = to_usb_interface(dev);
1130 	struct ims_pcu *pcu = usb_get_intfdata(intf);
1131 	int value;
1132 	int error;
1133 
1134 	error = kstrtoint(buf, 0, &value);
1135 	if (error)
1136 		return error;
1137 
1138 	if (value != 1)
1139 		return -EINVAL;
1140 
1141 	dev_info(pcu->dev, "Attempting to reset device\n");
1142 
1143 	error = ims_pcu_execute_command(pcu, PCU_RESET, &reset_byte, 1);
1144 	if (error) {
1145 		dev_info(pcu->dev,
1146 			 "Failed to reset device, error: %d\n",
1147 			 error);
1148 		return error;
1149 	}
1150 
1151 	return count;
1152 }
1153 
1154 static DEVICE_ATTR(reset_device, S_IWUSR, NULL, ims_pcu_reset_device);
1155 
ims_pcu_update_firmware_store(struct device * dev,struct device_attribute * dattr,const char * buf,size_t count)1156 static ssize_t ims_pcu_update_firmware_store(struct device *dev,
1157 					     struct device_attribute *dattr,
1158 					     const char *buf, size_t count)
1159 {
1160 	struct usb_interface *intf = to_usb_interface(dev);
1161 	struct ims_pcu *pcu = usb_get_intfdata(intf);
1162 	const struct firmware *fw = NULL;
1163 	int value;
1164 	int error;
1165 
1166 	error = kstrtoint(buf, 0, &value);
1167 	if (error)
1168 		return error;
1169 
1170 	if (value != 1)
1171 		return -EINVAL;
1172 
1173 	error = mutex_lock_interruptible(&pcu->cmd_mutex);
1174 	if (error)
1175 		return error;
1176 
1177 	error = request_ihex_firmware(&fw, IMS_PCU_FIRMWARE_NAME, pcu->dev);
1178 	if (error) {
1179 		dev_err(pcu->dev, "Failed to request firmware %s, error: %d\n",
1180 			IMS_PCU_FIRMWARE_NAME, error);
1181 		goto out;
1182 	}
1183 
1184 	/*
1185 	 * If we are already in bootloader mode we can proceed with
1186 	 * flashing the firmware.
1187 	 *
1188 	 * If we are in application mode, then we need to switch into
1189 	 * bootloader mode, which will cause the device to disconnect
1190 	 * and reconnect as different device.
1191 	 */
1192 	if (pcu->bootloader_mode)
1193 		error = ims_pcu_handle_firmware_update(pcu, fw);
1194 	else
1195 		error = ims_pcu_switch_to_bootloader(pcu);
1196 
1197 	release_firmware(fw);
1198 
1199 out:
1200 	mutex_unlock(&pcu->cmd_mutex);
1201 	return error ?: count;
1202 }
1203 
1204 static DEVICE_ATTR(update_firmware, S_IWUSR,
1205 		   NULL, ims_pcu_update_firmware_store);
1206 
1207 static ssize_t
ims_pcu_update_firmware_status_show(struct device * dev,struct device_attribute * dattr,char * buf)1208 ims_pcu_update_firmware_status_show(struct device *dev,
1209 				    struct device_attribute *dattr,
1210 				    char *buf)
1211 {
1212 	struct usb_interface *intf = to_usb_interface(dev);
1213 	struct ims_pcu *pcu = usb_get_intfdata(intf);
1214 
1215 	return scnprintf(buf, PAGE_SIZE, "%d\n", pcu->update_firmware_status);
1216 }
1217 
1218 static DEVICE_ATTR(update_firmware_status, S_IRUGO,
1219 		   ims_pcu_update_firmware_status_show, NULL);
1220 
1221 static struct attribute *ims_pcu_attrs[] = {
1222 	&ims_pcu_attr_part_number.dattr.attr,
1223 	&ims_pcu_attr_serial_number.dattr.attr,
1224 	&ims_pcu_attr_date_of_manufacturing.dattr.attr,
1225 	&ims_pcu_attr_fw_version.dattr.attr,
1226 	&ims_pcu_attr_bl_version.dattr.attr,
1227 	&ims_pcu_attr_reset_reason.dattr.attr,
1228 	&dev_attr_reset_device.attr,
1229 	&dev_attr_update_firmware.attr,
1230 	&dev_attr_update_firmware_status.attr,
1231 	NULL
1232 };
1233 
ims_pcu_is_attr_visible(struct kobject * kobj,struct attribute * attr,int n)1234 static umode_t ims_pcu_is_attr_visible(struct kobject *kobj,
1235 				       struct attribute *attr, int n)
1236 {
1237 	struct device *dev = kobj_to_dev(kobj);
1238 	struct usb_interface *intf = to_usb_interface(dev);
1239 	struct ims_pcu *pcu = usb_get_intfdata(intf);
1240 	umode_t mode = attr->mode;
1241 
1242 	if (pcu->bootloader_mode) {
1243 		if (attr != &dev_attr_update_firmware_status.attr &&
1244 		    attr != &dev_attr_update_firmware.attr &&
1245 		    attr != &dev_attr_reset_device.attr) {
1246 			mode = 0;
1247 		}
1248 	} else {
1249 		if (attr == &dev_attr_update_firmware_status.attr)
1250 			mode = 0;
1251 	}
1252 
1253 	return mode;
1254 }
1255 
1256 static const struct attribute_group ims_pcu_attr_group = {
1257 	.is_visible	= ims_pcu_is_attr_visible,
1258 	.attrs		= ims_pcu_attrs,
1259 };
1260 
1261 /* Support for a separate OFN attribute group */
1262 
1263 #define OFN_REG_RESULT_OFFSET	2
1264 
ims_pcu_read_ofn_config(struct ims_pcu * pcu,u8 addr,u8 * data)1265 static int ims_pcu_read_ofn_config(struct ims_pcu *pcu, u8 addr, u8 *data)
1266 {
1267 	int error;
1268 	s16 result;
1269 
1270 	error = ims_pcu_execute_command(pcu, OFN_GET_CONFIG,
1271 					&addr, sizeof(addr));
1272 	if (error)
1273 		return error;
1274 
1275 	result = (s16)get_unaligned_le16(pcu->cmd_buf + OFN_REG_RESULT_OFFSET);
1276 	if (result < 0)
1277 		return -EIO;
1278 
1279 	/* We only need LSB */
1280 	*data = pcu->cmd_buf[OFN_REG_RESULT_OFFSET];
1281 	return 0;
1282 }
1283 
ims_pcu_write_ofn_config(struct ims_pcu * pcu,u8 addr,u8 data)1284 static int ims_pcu_write_ofn_config(struct ims_pcu *pcu, u8 addr, u8 data)
1285 {
1286 	u8 buffer[] = { addr, data };
1287 	int error;
1288 	s16 result;
1289 
1290 	error = ims_pcu_execute_command(pcu, OFN_SET_CONFIG,
1291 					&buffer, sizeof(buffer));
1292 	if (error)
1293 		return error;
1294 
1295 	result = (s16)get_unaligned_le16(pcu->cmd_buf + OFN_REG_RESULT_OFFSET);
1296 	if (result < 0)
1297 		return -EIO;
1298 
1299 	return 0;
1300 }
1301 
ims_pcu_ofn_reg_data_show(struct device * dev,struct device_attribute * dattr,char * buf)1302 static ssize_t ims_pcu_ofn_reg_data_show(struct device *dev,
1303 					 struct device_attribute *dattr,
1304 					 char *buf)
1305 {
1306 	struct usb_interface *intf = to_usb_interface(dev);
1307 	struct ims_pcu *pcu = usb_get_intfdata(intf);
1308 	int error;
1309 	u8 data;
1310 
1311 	mutex_lock(&pcu->cmd_mutex);
1312 	error = ims_pcu_read_ofn_config(pcu, pcu->ofn_reg_addr, &data);
1313 	mutex_unlock(&pcu->cmd_mutex);
1314 
1315 	if (error)
1316 		return error;
1317 
1318 	return scnprintf(buf, PAGE_SIZE, "%x\n", data);
1319 }
1320 
ims_pcu_ofn_reg_data_store(struct device * dev,struct device_attribute * dattr,const char * buf,size_t count)1321 static ssize_t ims_pcu_ofn_reg_data_store(struct device *dev,
1322 					  struct device_attribute *dattr,
1323 					  const char *buf, size_t count)
1324 {
1325 	struct usb_interface *intf = to_usb_interface(dev);
1326 	struct ims_pcu *pcu = usb_get_intfdata(intf);
1327 	int error;
1328 	u8 value;
1329 
1330 	error = kstrtou8(buf, 0, &value);
1331 	if (error)
1332 		return error;
1333 
1334 	mutex_lock(&pcu->cmd_mutex);
1335 	error = ims_pcu_write_ofn_config(pcu, pcu->ofn_reg_addr, value);
1336 	mutex_unlock(&pcu->cmd_mutex);
1337 
1338 	return error ?: count;
1339 }
1340 
1341 static DEVICE_ATTR(reg_data, S_IRUGO | S_IWUSR,
1342 		   ims_pcu_ofn_reg_data_show, ims_pcu_ofn_reg_data_store);
1343 
ims_pcu_ofn_reg_addr_show(struct device * dev,struct device_attribute * dattr,char * buf)1344 static ssize_t ims_pcu_ofn_reg_addr_show(struct device *dev,
1345 					 struct device_attribute *dattr,
1346 					 char *buf)
1347 {
1348 	struct usb_interface *intf = to_usb_interface(dev);
1349 	struct ims_pcu *pcu = usb_get_intfdata(intf);
1350 	int error;
1351 
1352 	mutex_lock(&pcu->cmd_mutex);
1353 	error = scnprintf(buf, PAGE_SIZE, "%x\n", pcu->ofn_reg_addr);
1354 	mutex_unlock(&pcu->cmd_mutex);
1355 
1356 	return error;
1357 }
1358 
ims_pcu_ofn_reg_addr_store(struct device * dev,struct device_attribute * dattr,const char * buf,size_t count)1359 static ssize_t ims_pcu_ofn_reg_addr_store(struct device *dev,
1360 					  struct device_attribute *dattr,
1361 					  const char *buf, size_t count)
1362 {
1363 	struct usb_interface *intf = to_usb_interface(dev);
1364 	struct ims_pcu *pcu = usb_get_intfdata(intf);
1365 	int error;
1366 	u8 value;
1367 
1368 	error = kstrtou8(buf, 0, &value);
1369 	if (error)
1370 		return error;
1371 
1372 	mutex_lock(&pcu->cmd_mutex);
1373 	pcu->ofn_reg_addr = value;
1374 	mutex_unlock(&pcu->cmd_mutex);
1375 
1376 	return count;
1377 }
1378 
1379 static DEVICE_ATTR(reg_addr, S_IRUGO | S_IWUSR,
1380 		   ims_pcu_ofn_reg_addr_show, ims_pcu_ofn_reg_addr_store);
1381 
1382 struct ims_pcu_ofn_bit_attribute {
1383 	struct device_attribute dattr;
1384 	u8 addr;
1385 	u8 nr;
1386 };
1387 
ims_pcu_ofn_bit_show(struct device * dev,struct device_attribute * dattr,char * buf)1388 static ssize_t ims_pcu_ofn_bit_show(struct device *dev,
1389 				    struct device_attribute *dattr,
1390 				    char *buf)
1391 {
1392 	struct usb_interface *intf = to_usb_interface(dev);
1393 	struct ims_pcu *pcu = usb_get_intfdata(intf);
1394 	struct ims_pcu_ofn_bit_attribute *attr =
1395 		container_of(dattr, struct ims_pcu_ofn_bit_attribute, dattr);
1396 	int error;
1397 	u8 data;
1398 
1399 	mutex_lock(&pcu->cmd_mutex);
1400 	error = ims_pcu_read_ofn_config(pcu, attr->addr, &data);
1401 	mutex_unlock(&pcu->cmd_mutex);
1402 
1403 	if (error)
1404 		return error;
1405 
1406 	return scnprintf(buf, PAGE_SIZE, "%d\n", !!(data & (1 << attr->nr)));
1407 }
1408 
ims_pcu_ofn_bit_store(struct device * dev,struct device_attribute * dattr,const char * buf,size_t count)1409 static ssize_t ims_pcu_ofn_bit_store(struct device *dev,
1410 				     struct device_attribute *dattr,
1411 				     const char *buf, size_t count)
1412 {
1413 	struct usb_interface *intf = to_usb_interface(dev);
1414 	struct ims_pcu *pcu = usb_get_intfdata(intf);
1415 	struct ims_pcu_ofn_bit_attribute *attr =
1416 		container_of(dattr, struct ims_pcu_ofn_bit_attribute, dattr);
1417 	int error;
1418 	int value;
1419 	u8 data;
1420 
1421 	error = kstrtoint(buf, 0, &value);
1422 	if (error)
1423 		return error;
1424 
1425 	if (value > 1)
1426 		return -EINVAL;
1427 
1428 	mutex_lock(&pcu->cmd_mutex);
1429 
1430 	error = ims_pcu_read_ofn_config(pcu, attr->addr, &data);
1431 	if (!error) {
1432 		if (value)
1433 			data |= 1U << attr->nr;
1434 		else
1435 			data &= ~(1U << attr->nr);
1436 
1437 		error = ims_pcu_write_ofn_config(pcu, attr->addr, data);
1438 	}
1439 
1440 	mutex_unlock(&pcu->cmd_mutex);
1441 
1442 	return error ?: count;
1443 }
1444 
1445 #define IMS_PCU_OFN_BIT_ATTR(_field, _addr, _nr)			\
1446 struct ims_pcu_ofn_bit_attribute ims_pcu_ofn_attr_##_field = {		\
1447 	.dattr = __ATTR(_field, S_IWUSR | S_IRUGO,			\
1448 			ims_pcu_ofn_bit_show, ims_pcu_ofn_bit_store),	\
1449 	.addr = _addr,							\
1450 	.nr = _nr,							\
1451 }
1452 
1453 static IMS_PCU_OFN_BIT_ATTR(engine_enable,   0x60, 7);
1454 static IMS_PCU_OFN_BIT_ATTR(speed_enable,    0x60, 6);
1455 static IMS_PCU_OFN_BIT_ATTR(assert_enable,   0x60, 5);
1456 static IMS_PCU_OFN_BIT_ATTR(xyquant_enable,  0x60, 4);
1457 static IMS_PCU_OFN_BIT_ATTR(xyscale_enable,  0x60, 1);
1458 
1459 static IMS_PCU_OFN_BIT_ATTR(scale_x2,        0x63, 6);
1460 static IMS_PCU_OFN_BIT_ATTR(scale_y2,        0x63, 7);
1461 
1462 static struct attribute *ims_pcu_ofn_attrs[] = {
1463 	&dev_attr_reg_data.attr,
1464 	&dev_attr_reg_addr.attr,
1465 	&ims_pcu_ofn_attr_engine_enable.dattr.attr,
1466 	&ims_pcu_ofn_attr_speed_enable.dattr.attr,
1467 	&ims_pcu_ofn_attr_assert_enable.dattr.attr,
1468 	&ims_pcu_ofn_attr_xyquant_enable.dattr.attr,
1469 	&ims_pcu_ofn_attr_xyscale_enable.dattr.attr,
1470 	&ims_pcu_ofn_attr_scale_x2.dattr.attr,
1471 	&ims_pcu_ofn_attr_scale_y2.dattr.attr,
1472 	NULL
1473 };
1474 
1475 static const struct attribute_group ims_pcu_ofn_attr_group = {
1476 	.name	= "ofn",
1477 	.attrs	= ims_pcu_ofn_attrs,
1478 };
1479 
ims_pcu_irq(struct urb * urb)1480 static void ims_pcu_irq(struct urb *urb)
1481 {
1482 	struct ims_pcu *pcu = urb->context;
1483 	int retval, status;
1484 
1485 	status = urb->status;
1486 
1487 	switch (status) {
1488 	case 0:
1489 		/* success */
1490 		break;
1491 	case -ECONNRESET:
1492 	case -ENOENT:
1493 	case -ESHUTDOWN:
1494 		/* this urb is terminated, clean up */
1495 		dev_dbg(pcu->dev, "%s - urb shutting down with status: %d\n",
1496 			__func__, status);
1497 		return;
1498 	default:
1499 		dev_dbg(pcu->dev, "%s - nonzero urb status received: %d\n",
1500 			__func__, status);
1501 		goto exit;
1502 	}
1503 
1504 	dev_dbg(pcu->dev, "%s: received %d: %*ph\n", __func__,
1505 		urb->actual_length, urb->actual_length, pcu->urb_in_buf);
1506 
1507 	if (urb == pcu->urb_in)
1508 		ims_pcu_process_data(pcu, urb);
1509 
1510 exit:
1511 	retval = usb_submit_urb(urb, GFP_ATOMIC);
1512 	if (retval && retval != -ENODEV)
1513 		dev_err(pcu->dev, "%s - usb_submit_urb failed with result %d\n",
1514 			__func__, retval);
1515 }
1516 
ims_pcu_buffers_alloc(struct ims_pcu * pcu)1517 static int ims_pcu_buffers_alloc(struct ims_pcu *pcu)
1518 {
1519 	int error;
1520 
1521 	pcu->urb_in_buf = usb_alloc_coherent(pcu->udev, pcu->max_in_size,
1522 					     GFP_KERNEL, &pcu->read_dma);
1523 	if (!pcu->urb_in_buf) {
1524 		dev_err(pcu->dev,
1525 			"Failed to allocate memory for read buffer\n");
1526 		return -ENOMEM;
1527 	}
1528 
1529 	pcu->urb_in = usb_alloc_urb(0, GFP_KERNEL);
1530 	if (!pcu->urb_in) {
1531 		dev_err(pcu->dev, "Failed to allocate input URB\n");
1532 		error = -ENOMEM;
1533 		goto err_free_urb_in_buf;
1534 	}
1535 
1536 	pcu->urb_in->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1537 	pcu->urb_in->transfer_dma = pcu->read_dma;
1538 
1539 	usb_fill_bulk_urb(pcu->urb_in, pcu->udev,
1540 			  usb_rcvbulkpipe(pcu->udev,
1541 					  pcu->ep_in->bEndpointAddress),
1542 			  pcu->urb_in_buf, pcu->max_in_size,
1543 			  ims_pcu_irq, pcu);
1544 
1545 	/*
1546 	 * We are using usb_bulk_msg() for sending so there is no point
1547 	 * in allocating memory with usb_alloc_coherent().
1548 	 */
1549 	pcu->urb_out_buf = kmalloc(pcu->max_out_size, GFP_KERNEL);
1550 	if (!pcu->urb_out_buf) {
1551 		dev_err(pcu->dev, "Failed to allocate memory for write buffer\n");
1552 		error = -ENOMEM;
1553 		goto err_free_in_urb;
1554 	}
1555 
1556 	pcu->urb_ctrl_buf = usb_alloc_coherent(pcu->udev, pcu->max_ctrl_size,
1557 					       GFP_KERNEL, &pcu->ctrl_dma);
1558 	if (!pcu->urb_ctrl_buf) {
1559 		dev_err(pcu->dev,
1560 			"Failed to allocate memory for read buffer\n");
1561 		error = -ENOMEM;
1562 		goto err_free_urb_out_buf;
1563 	}
1564 
1565 	pcu->urb_ctrl = usb_alloc_urb(0, GFP_KERNEL);
1566 	if (!pcu->urb_ctrl) {
1567 		dev_err(pcu->dev, "Failed to allocate input URB\n");
1568 		error = -ENOMEM;
1569 		goto err_free_urb_ctrl_buf;
1570 	}
1571 
1572 	pcu->urb_ctrl->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1573 	pcu->urb_ctrl->transfer_dma = pcu->ctrl_dma;
1574 
1575 	usb_fill_int_urb(pcu->urb_ctrl, pcu->udev,
1576 			  usb_rcvintpipe(pcu->udev,
1577 					 pcu->ep_ctrl->bEndpointAddress),
1578 			  pcu->urb_ctrl_buf, pcu->max_ctrl_size,
1579 			  ims_pcu_irq, pcu, pcu->ep_ctrl->bInterval);
1580 
1581 	return 0;
1582 
1583 err_free_urb_ctrl_buf:
1584 	usb_free_coherent(pcu->udev, pcu->max_ctrl_size,
1585 			  pcu->urb_ctrl_buf, pcu->ctrl_dma);
1586 err_free_urb_out_buf:
1587 	kfree(pcu->urb_out_buf);
1588 err_free_in_urb:
1589 	usb_free_urb(pcu->urb_in);
1590 err_free_urb_in_buf:
1591 	usb_free_coherent(pcu->udev, pcu->max_in_size,
1592 			  pcu->urb_in_buf, pcu->read_dma);
1593 	return error;
1594 }
1595 
ims_pcu_buffers_free(struct ims_pcu * pcu)1596 static void ims_pcu_buffers_free(struct ims_pcu *pcu)
1597 {
1598 	usb_kill_urb(pcu->urb_in);
1599 	usb_free_urb(pcu->urb_in);
1600 
1601 	usb_free_coherent(pcu->udev, pcu->max_out_size,
1602 			  pcu->urb_in_buf, pcu->read_dma);
1603 
1604 	kfree(pcu->urb_out_buf);
1605 
1606 	usb_kill_urb(pcu->urb_ctrl);
1607 	usb_free_urb(pcu->urb_ctrl);
1608 
1609 	usb_free_coherent(pcu->udev, pcu->max_ctrl_size,
1610 			  pcu->urb_ctrl_buf, pcu->ctrl_dma);
1611 }
1612 
1613 static const struct usb_cdc_union_desc *
ims_pcu_get_cdc_union_desc(struct usb_interface * intf)1614 ims_pcu_get_cdc_union_desc(struct usb_interface *intf)
1615 {
1616 	const void *buf = intf->altsetting->extra;
1617 	size_t buflen = intf->altsetting->extralen;
1618 	struct usb_cdc_union_desc *union_desc;
1619 
1620 	if (!buf) {
1621 		dev_err(&intf->dev, "Missing descriptor data\n");
1622 		return NULL;
1623 	}
1624 
1625 	if (!buflen) {
1626 		dev_err(&intf->dev, "Zero length descriptor\n");
1627 		return NULL;
1628 	}
1629 
1630 	while (buflen >= sizeof(*union_desc)) {
1631 		union_desc = (struct usb_cdc_union_desc *)buf;
1632 
1633 		if (union_desc->bLength > buflen) {
1634 			dev_err(&intf->dev, "Too large descriptor\n");
1635 			return NULL;
1636 		}
1637 
1638 		if (union_desc->bDescriptorType == USB_DT_CS_INTERFACE &&
1639 		    union_desc->bDescriptorSubType == USB_CDC_UNION_TYPE) {
1640 			dev_dbg(&intf->dev, "Found union header\n");
1641 
1642 			if (union_desc->bLength >= sizeof(*union_desc))
1643 				return union_desc;
1644 
1645 			dev_err(&intf->dev,
1646 				"Union descriptor too short (%d vs %zd)\n",
1647 				union_desc->bLength, sizeof(*union_desc));
1648 			return NULL;
1649 		}
1650 
1651 		buflen -= union_desc->bLength;
1652 		buf += union_desc->bLength;
1653 	}
1654 
1655 	dev_err(&intf->dev, "Missing CDC union descriptor\n");
1656 	return NULL;
1657 }
1658 
ims_pcu_parse_cdc_data(struct usb_interface * intf,struct ims_pcu * pcu)1659 static int ims_pcu_parse_cdc_data(struct usb_interface *intf, struct ims_pcu *pcu)
1660 {
1661 	const struct usb_cdc_union_desc *union_desc;
1662 	struct usb_host_interface *alt;
1663 
1664 	union_desc = ims_pcu_get_cdc_union_desc(intf);
1665 	if (!union_desc)
1666 		return -EINVAL;
1667 
1668 	pcu->ctrl_intf = usb_ifnum_to_if(pcu->udev,
1669 					 union_desc->bMasterInterface0);
1670 	if (!pcu->ctrl_intf)
1671 		return -EINVAL;
1672 
1673 	alt = pcu->ctrl_intf->cur_altsetting;
1674 
1675 	if (alt->desc.bNumEndpoints < 1)
1676 		return -ENODEV;
1677 
1678 	pcu->ep_ctrl = &alt->endpoint[0].desc;
1679 	pcu->max_ctrl_size = usb_endpoint_maxp(pcu->ep_ctrl);
1680 
1681 	pcu->data_intf = usb_ifnum_to_if(pcu->udev,
1682 					 union_desc->bSlaveInterface0);
1683 	if (!pcu->data_intf)
1684 		return -EINVAL;
1685 
1686 	alt = pcu->data_intf->cur_altsetting;
1687 	if (alt->desc.bNumEndpoints != 2) {
1688 		dev_err(pcu->dev,
1689 			"Incorrect number of endpoints on data interface (%d)\n",
1690 			alt->desc.bNumEndpoints);
1691 		return -EINVAL;
1692 	}
1693 
1694 	pcu->ep_out = &alt->endpoint[0].desc;
1695 	if (!usb_endpoint_is_bulk_out(pcu->ep_out)) {
1696 		dev_err(pcu->dev,
1697 			"First endpoint on data interface is not BULK OUT\n");
1698 		return -EINVAL;
1699 	}
1700 
1701 	pcu->max_out_size = usb_endpoint_maxp(pcu->ep_out);
1702 	if (pcu->max_out_size < 8) {
1703 		dev_err(pcu->dev,
1704 			"Max OUT packet size is too small (%zd)\n",
1705 			pcu->max_out_size);
1706 		return -EINVAL;
1707 	}
1708 
1709 	pcu->ep_in = &alt->endpoint[1].desc;
1710 	if (!usb_endpoint_is_bulk_in(pcu->ep_in)) {
1711 		dev_err(pcu->dev,
1712 			"Second endpoint on data interface is not BULK IN\n");
1713 		return -EINVAL;
1714 	}
1715 
1716 	pcu->max_in_size = usb_endpoint_maxp(pcu->ep_in);
1717 	if (pcu->max_in_size < 8) {
1718 		dev_err(pcu->dev,
1719 			"Max IN packet size is too small (%zd)\n",
1720 			pcu->max_in_size);
1721 		return -EINVAL;
1722 	}
1723 
1724 	return 0;
1725 }
1726 
ims_pcu_start_io(struct ims_pcu * pcu)1727 static int ims_pcu_start_io(struct ims_pcu *pcu)
1728 {
1729 	int error;
1730 
1731 	error = usb_submit_urb(pcu->urb_ctrl, GFP_KERNEL);
1732 	if (error) {
1733 		dev_err(pcu->dev,
1734 			"Failed to start control IO - usb_submit_urb failed with result: %d\n",
1735 			error);
1736 		return -EIO;
1737 	}
1738 
1739 	error = usb_submit_urb(pcu->urb_in, GFP_KERNEL);
1740 	if (error) {
1741 		dev_err(pcu->dev,
1742 			"Failed to start IO - usb_submit_urb failed with result: %d\n",
1743 			error);
1744 		usb_kill_urb(pcu->urb_ctrl);
1745 		return -EIO;
1746 	}
1747 
1748 	return 0;
1749 }
1750 
ims_pcu_stop_io(struct ims_pcu * pcu)1751 static void ims_pcu_stop_io(struct ims_pcu *pcu)
1752 {
1753 	usb_kill_urb(pcu->urb_in);
1754 	usb_kill_urb(pcu->urb_ctrl);
1755 }
1756 
ims_pcu_line_setup(struct ims_pcu * pcu)1757 static int ims_pcu_line_setup(struct ims_pcu *pcu)
1758 {
1759 	struct usb_host_interface *interface = pcu->ctrl_intf->cur_altsetting;
1760 	struct usb_cdc_line_coding *line = (void *)pcu->cmd_buf;
1761 	int error;
1762 
1763 	memset(line, 0, sizeof(*line));
1764 	line->dwDTERate = cpu_to_le32(57600);
1765 	line->bDataBits = 8;
1766 
1767 	error = usb_control_msg(pcu->udev, usb_sndctrlpipe(pcu->udev, 0),
1768 				USB_CDC_REQ_SET_LINE_CODING,
1769 				USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1770 				0, interface->desc.bInterfaceNumber,
1771 				line, sizeof(struct usb_cdc_line_coding),
1772 				5000);
1773 	if (error < 0) {
1774 		dev_err(pcu->dev, "Failed to set line coding, error: %d\n",
1775 			error);
1776 		return error;
1777 	}
1778 
1779 	error = usb_control_msg(pcu->udev, usb_sndctrlpipe(pcu->udev, 0),
1780 				USB_CDC_REQ_SET_CONTROL_LINE_STATE,
1781 				USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1782 				0x03, interface->desc.bInterfaceNumber,
1783 				NULL, 0, 5000);
1784 	if (error < 0) {
1785 		dev_err(pcu->dev, "Failed to set line state, error: %d\n",
1786 			error);
1787 		return error;
1788 	}
1789 
1790 	return 0;
1791 }
1792 
ims_pcu_get_device_info(struct ims_pcu * pcu)1793 static int ims_pcu_get_device_info(struct ims_pcu *pcu)
1794 {
1795 	int error;
1796 
1797 	error = ims_pcu_get_info(pcu);
1798 	if (error)
1799 		return error;
1800 
1801 	error = ims_pcu_execute_query(pcu, GET_FW_VERSION);
1802 	if (error) {
1803 		dev_err(pcu->dev,
1804 			"GET_FW_VERSION command failed, error: %d\n", error);
1805 		return error;
1806 	}
1807 
1808 	snprintf(pcu->fw_version, sizeof(pcu->fw_version),
1809 		 "%02d%02d%02d%02d.%c%c",
1810 		 pcu->cmd_buf[2], pcu->cmd_buf[3], pcu->cmd_buf[4], pcu->cmd_buf[5],
1811 		 pcu->cmd_buf[6], pcu->cmd_buf[7]);
1812 
1813 	error = ims_pcu_execute_query(pcu, GET_BL_VERSION);
1814 	if (error) {
1815 		dev_err(pcu->dev,
1816 			"GET_BL_VERSION command failed, error: %d\n", error);
1817 		return error;
1818 	}
1819 
1820 	snprintf(pcu->bl_version, sizeof(pcu->bl_version),
1821 		 "%02d%02d%02d%02d.%c%c",
1822 		 pcu->cmd_buf[2], pcu->cmd_buf[3], pcu->cmd_buf[4], pcu->cmd_buf[5],
1823 		 pcu->cmd_buf[6], pcu->cmd_buf[7]);
1824 
1825 	error = ims_pcu_execute_query(pcu, RESET_REASON);
1826 	if (error) {
1827 		dev_err(pcu->dev,
1828 			"RESET_REASON command failed, error: %d\n", error);
1829 		return error;
1830 	}
1831 
1832 	snprintf(pcu->reset_reason, sizeof(pcu->reset_reason),
1833 		 "%02x", pcu->cmd_buf[IMS_PCU_DATA_OFFSET]);
1834 
1835 	dev_dbg(pcu->dev,
1836 		"P/N: %s, MD: %s, S/N: %s, FW: %s, BL: %s, RR: %s\n",
1837 		pcu->part_number,
1838 		pcu->date_of_manufacturing,
1839 		pcu->serial_number,
1840 		pcu->fw_version,
1841 		pcu->bl_version,
1842 		pcu->reset_reason);
1843 
1844 	return 0;
1845 }
1846 
ims_pcu_identify_type(struct ims_pcu * pcu,u8 * device_id)1847 static int ims_pcu_identify_type(struct ims_pcu *pcu, u8 *device_id)
1848 {
1849 	int error;
1850 
1851 	error = ims_pcu_execute_query(pcu, GET_DEVICE_ID);
1852 	if (error) {
1853 		dev_err(pcu->dev,
1854 			"GET_DEVICE_ID command failed, error: %d\n", error);
1855 		return error;
1856 	}
1857 
1858 	*device_id = pcu->cmd_buf[IMS_PCU_DATA_OFFSET];
1859 	dev_dbg(pcu->dev, "Detected device ID: %d\n", *device_id);
1860 
1861 	return 0;
1862 }
1863 
ims_pcu_init_application_mode(struct ims_pcu * pcu)1864 static int ims_pcu_init_application_mode(struct ims_pcu *pcu)
1865 {
1866 	static atomic_t device_no = ATOMIC_INIT(-1);
1867 
1868 	const struct ims_pcu_device_info *info;
1869 	int error;
1870 
1871 	error = ims_pcu_get_device_info(pcu);
1872 	if (error) {
1873 		/* Device does not respond to basic queries, hopeless */
1874 		return error;
1875 	}
1876 
1877 	error = ims_pcu_identify_type(pcu, &pcu->device_id);
1878 	if (error) {
1879 		dev_err(pcu->dev,
1880 			"Failed to identify device, error: %d\n", error);
1881 		/*
1882 		 * Do not signal error, but do not create input nor
1883 		 * backlight devices either, let userspace figure this
1884 		 * out (flash a new firmware?).
1885 		 */
1886 		return 0;
1887 	}
1888 
1889 	if (pcu->device_id >= ARRAY_SIZE(ims_pcu_device_info) ||
1890 	    !ims_pcu_device_info[pcu->device_id].keymap) {
1891 		dev_err(pcu->dev, "Device ID %d is not valid\n", pcu->device_id);
1892 		/* Same as above, punt to userspace */
1893 		return 0;
1894 	}
1895 
1896 	/* Device appears to be operable, complete initialization */
1897 	pcu->device_no = atomic_inc_return(&device_no);
1898 
1899 	/*
1900 	 * PCU-B devices, both GEN_1 and GEN_2 do not have OFN sensor
1901 	 */
1902 	if (pcu->device_id != IMS_PCU_PCU_B_DEVICE_ID) {
1903 		error = sysfs_create_group(&pcu->dev->kobj,
1904 					   &ims_pcu_ofn_attr_group);
1905 		if (error)
1906 			return error;
1907 	}
1908 
1909 	error = ims_pcu_setup_backlight(pcu);
1910 	if (error)
1911 		return error;
1912 
1913 	info = &ims_pcu_device_info[pcu->device_id];
1914 	error = ims_pcu_setup_buttons(pcu, info->keymap, info->keymap_len);
1915 	if (error)
1916 		goto err_destroy_backlight;
1917 
1918 	if (info->has_gamepad) {
1919 		error = ims_pcu_setup_gamepad(pcu);
1920 		if (error)
1921 			goto err_destroy_buttons;
1922 	}
1923 
1924 	pcu->setup_complete = true;
1925 
1926 	return 0;
1927 
1928 err_destroy_buttons:
1929 	ims_pcu_destroy_buttons(pcu);
1930 err_destroy_backlight:
1931 	ims_pcu_destroy_backlight(pcu);
1932 	return error;
1933 }
1934 
ims_pcu_destroy_application_mode(struct ims_pcu * pcu)1935 static void ims_pcu_destroy_application_mode(struct ims_pcu *pcu)
1936 {
1937 	if (pcu->setup_complete) {
1938 		pcu->setup_complete = false;
1939 		mb(); /* make sure flag setting is not reordered */
1940 
1941 		if (pcu->gamepad)
1942 			ims_pcu_destroy_gamepad(pcu);
1943 		ims_pcu_destroy_buttons(pcu);
1944 		ims_pcu_destroy_backlight(pcu);
1945 
1946 		if (pcu->device_id != IMS_PCU_PCU_B_DEVICE_ID)
1947 			sysfs_remove_group(&pcu->dev->kobj,
1948 					   &ims_pcu_ofn_attr_group);
1949 	}
1950 }
1951 
ims_pcu_init_bootloader_mode(struct ims_pcu * pcu)1952 static int ims_pcu_init_bootloader_mode(struct ims_pcu *pcu)
1953 {
1954 	int error;
1955 
1956 	error = ims_pcu_execute_bl_command(pcu, QUERY_DEVICE, NULL, 0,
1957 					   IMS_PCU_CMD_RESPONSE_TIMEOUT);
1958 	if (error) {
1959 		dev_err(pcu->dev, "Bootloader does not respond, aborting\n");
1960 		return error;
1961 	}
1962 
1963 	pcu->fw_start_addr =
1964 		get_unaligned_le32(&pcu->cmd_buf[IMS_PCU_DATA_OFFSET + 11]);
1965 	pcu->fw_end_addr =
1966 		get_unaligned_le32(&pcu->cmd_buf[IMS_PCU_DATA_OFFSET + 15]);
1967 
1968 	dev_info(pcu->dev,
1969 		 "Device is in bootloader mode (addr 0x%08x-0x%08x), requesting firmware\n",
1970 		 pcu->fw_start_addr, pcu->fw_end_addr);
1971 
1972 	error = request_firmware_nowait(THIS_MODULE, true,
1973 					IMS_PCU_FIRMWARE_NAME,
1974 					pcu->dev, GFP_KERNEL, pcu,
1975 					ims_pcu_process_async_firmware);
1976 	if (error) {
1977 		/* This error is not fatal, let userspace have another chance */
1978 		complete(&pcu->async_firmware_done);
1979 	}
1980 
1981 	return 0;
1982 }
1983 
ims_pcu_destroy_bootloader_mode(struct ims_pcu * pcu)1984 static void ims_pcu_destroy_bootloader_mode(struct ims_pcu *pcu)
1985 {
1986 	/* Make sure our initial firmware request has completed */
1987 	wait_for_completion(&pcu->async_firmware_done);
1988 }
1989 
1990 #define IMS_PCU_APPLICATION_MODE	0
1991 #define IMS_PCU_BOOTLOADER_MODE		1
1992 
1993 static struct usb_driver ims_pcu_driver;
1994 
ims_pcu_probe(struct usb_interface * intf,const struct usb_device_id * id)1995 static int ims_pcu_probe(struct usb_interface *intf,
1996 			 const struct usb_device_id *id)
1997 {
1998 	struct usb_device *udev = interface_to_usbdev(intf);
1999 	struct ims_pcu *pcu;
2000 	int error;
2001 
2002 	pcu = kzalloc(sizeof(struct ims_pcu), GFP_KERNEL);
2003 	if (!pcu)
2004 		return -ENOMEM;
2005 
2006 	pcu->dev = &intf->dev;
2007 	pcu->udev = udev;
2008 	pcu->bootloader_mode = id->driver_info == IMS_PCU_BOOTLOADER_MODE;
2009 	mutex_init(&pcu->cmd_mutex);
2010 	init_completion(&pcu->cmd_done);
2011 	init_completion(&pcu->async_firmware_done);
2012 
2013 	error = ims_pcu_parse_cdc_data(intf, pcu);
2014 	if (error)
2015 		goto err_free_mem;
2016 
2017 	error = usb_driver_claim_interface(&ims_pcu_driver,
2018 					   pcu->data_intf, pcu);
2019 	if (error) {
2020 		dev_err(&intf->dev,
2021 			"Unable to claim corresponding data interface: %d\n",
2022 			error);
2023 		goto err_free_mem;
2024 	}
2025 
2026 	usb_set_intfdata(pcu->ctrl_intf, pcu);
2027 
2028 	error = ims_pcu_buffers_alloc(pcu);
2029 	if (error)
2030 		goto err_unclaim_intf;
2031 
2032 	error = ims_pcu_start_io(pcu);
2033 	if (error)
2034 		goto err_free_buffers;
2035 
2036 	error = ims_pcu_line_setup(pcu);
2037 	if (error)
2038 		goto err_stop_io;
2039 
2040 	error = sysfs_create_group(&intf->dev.kobj, &ims_pcu_attr_group);
2041 	if (error)
2042 		goto err_stop_io;
2043 
2044 	error = pcu->bootloader_mode ?
2045 			ims_pcu_init_bootloader_mode(pcu) :
2046 			ims_pcu_init_application_mode(pcu);
2047 	if (error)
2048 		goto err_remove_sysfs;
2049 
2050 	return 0;
2051 
2052 err_remove_sysfs:
2053 	sysfs_remove_group(&intf->dev.kobj, &ims_pcu_attr_group);
2054 err_stop_io:
2055 	ims_pcu_stop_io(pcu);
2056 err_free_buffers:
2057 	ims_pcu_buffers_free(pcu);
2058 err_unclaim_intf:
2059 	usb_driver_release_interface(&ims_pcu_driver, pcu->data_intf);
2060 err_free_mem:
2061 	kfree(pcu);
2062 	return error;
2063 }
2064 
ims_pcu_disconnect(struct usb_interface * intf)2065 static void ims_pcu_disconnect(struct usb_interface *intf)
2066 {
2067 	struct ims_pcu *pcu = usb_get_intfdata(intf);
2068 	struct usb_host_interface *alt = intf->cur_altsetting;
2069 
2070 	usb_set_intfdata(intf, NULL);
2071 
2072 	/*
2073 	 * See if we are dealing with control or data interface. The cleanup
2074 	 * happens when we unbind primary (control) interface.
2075 	 */
2076 	if (alt->desc.bInterfaceClass != USB_CLASS_COMM)
2077 		return;
2078 
2079 	sysfs_remove_group(&intf->dev.kobj, &ims_pcu_attr_group);
2080 
2081 	ims_pcu_stop_io(pcu);
2082 
2083 	if (pcu->bootloader_mode)
2084 		ims_pcu_destroy_bootloader_mode(pcu);
2085 	else
2086 		ims_pcu_destroy_application_mode(pcu);
2087 
2088 	ims_pcu_buffers_free(pcu);
2089 	kfree(pcu);
2090 }
2091 
2092 #ifdef CONFIG_PM
ims_pcu_suspend(struct usb_interface * intf,pm_message_t message)2093 static int ims_pcu_suspend(struct usb_interface *intf,
2094 			   pm_message_t message)
2095 {
2096 	struct ims_pcu *pcu = usb_get_intfdata(intf);
2097 	struct usb_host_interface *alt = intf->cur_altsetting;
2098 
2099 	if (alt->desc.bInterfaceClass == USB_CLASS_COMM)
2100 		ims_pcu_stop_io(pcu);
2101 
2102 	return 0;
2103 }
2104 
ims_pcu_resume(struct usb_interface * intf)2105 static int ims_pcu_resume(struct usb_interface *intf)
2106 {
2107 	struct ims_pcu *pcu = usb_get_intfdata(intf);
2108 	struct usb_host_interface *alt = intf->cur_altsetting;
2109 	int retval = 0;
2110 
2111 	if (alt->desc.bInterfaceClass == USB_CLASS_COMM) {
2112 		retval = ims_pcu_start_io(pcu);
2113 		if (retval == 0)
2114 			retval = ims_pcu_line_setup(pcu);
2115 	}
2116 
2117 	return retval;
2118 }
2119 #endif
2120 
2121 static const struct usb_device_id ims_pcu_id_table[] = {
2122 	{
2123 		USB_DEVICE_AND_INTERFACE_INFO(0x04d8, 0x0082,
2124 					USB_CLASS_COMM,
2125 					USB_CDC_SUBCLASS_ACM,
2126 					USB_CDC_ACM_PROTO_AT_V25TER),
2127 		.driver_info = IMS_PCU_APPLICATION_MODE,
2128 	},
2129 	{
2130 		USB_DEVICE_AND_INTERFACE_INFO(0x04d8, 0x0083,
2131 					USB_CLASS_COMM,
2132 					USB_CDC_SUBCLASS_ACM,
2133 					USB_CDC_ACM_PROTO_AT_V25TER),
2134 		.driver_info = IMS_PCU_BOOTLOADER_MODE,
2135 	},
2136 	{ }
2137 };
2138 
2139 static struct usb_driver ims_pcu_driver = {
2140 	.name			= "ims_pcu",
2141 	.id_table		= ims_pcu_id_table,
2142 	.probe			= ims_pcu_probe,
2143 	.disconnect		= ims_pcu_disconnect,
2144 #ifdef CONFIG_PM
2145 	.suspend		= ims_pcu_suspend,
2146 	.resume			= ims_pcu_resume,
2147 	.reset_resume		= ims_pcu_resume,
2148 #endif
2149 };
2150 
2151 module_usb_driver(ims_pcu_driver);
2152 
2153 MODULE_DESCRIPTION("IMS Passenger Control Unit driver");
2154 MODULE_AUTHOR("Dmitry Torokhov <dmitry.torokhov@gmail.com>");
2155 MODULE_LICENSE("GPL");
2156