1// SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
2/*
3 * UCSI driver for STMicroelectronics STM32G0 Type-C PD controller
4 *
5 * Copyright (C) 2022, STMicroelectronics - All Rights Reserved
6 * Author: Fabrice Gasnier <fabrice.gasnier@foss.st.com>.
7 */
8
9#include <linux/delay.h>
10#include <linux/firmware.h>
11#include <linux/i2c.h>
12#include <linux/interrupt.h>
13#include <linux/module.h>
14#include <linux/platform_device.h>
15#include <asm/unaligned.h>
16
17#include "ucsi.h"
18
19/* STM32G0 I2C bootloader addr: 0b1010001x (See AN2606) */
20#define STM32G0_I2C_BL_ADDR (0xa2 >> 1)
21
22/* STM32G0 I2C bootloader max data size */
23#define STM32G0_I2C_BL_SZ 256
24
25/* STM32 I2C bootloader commands (See AN4221) */
26#define STM32_CMD_GVR 0x01 /* Gets the bootloader version */
27#define STM32_CMD_GVR_LEN 1
28#define STM32_CMD_RM 0x11 /* Reag memory */
29#define STM32_CMD_WM 0x31 /* Write memory */
30#define STM32_CMD_ADDR_LEN 5 /* Address len for go, mem write... */
31#define STM32_CMD_ERASE 0x44 /* Erase page, bank or all */
32#define STM32_CMD_ERASE_SPECIAL_LEN 3
33#define STM32_CMD_GLOBAL_MASS_ERASE 0xffff /* All-bank erase */
34
35/* STM32 I2C bootloader answer status */
36#define STM32G0_I2C_BL_ACK 0x79
37#define STM32G0_I2C_BL_NACK 0x1f
38#define STM32G0_I2C_BL_BUSY 0x76
39
40/* STM32G0 flash definitions */
41#define STM32G0_USER_OPTION_BYTES 0x1fff7800
42#define STM32G0_USER_OB_NBOOT0 BIT(26)
43#define STM32G0_USER_OB_NBOOT_SEL BIT(24)
44#define STM32G0_USER_OB_BOOT_MAIN (STM32G0_USER_OB_NBOOT0 | STM32G0_USER_OB_NBOOT_SEL)
45#define STM32G0_MAIN_MEM_ADDR 0x08000000
46
47/* STM32 Firmware definitions: additional commands */
48#define STM32G0_FW_GETVER 0x00 /* Gets the firmware version */
49#define STM32G0_FW_GETVER_LEN 4
50#define STM32G0_FW_RSTGOBL 0x21 /* Reset and go to bootloader */
51#define STM32G0_FW_KEYWORD 0xa56959a6
52
53/* ucsi_stm32g0_fw_info located at the end of the firmware */
54struct ucsi_stm32g0_fw_info {
55 u32 version;
56 u32 keyword;
57};
58
59struct ucsi_stm32g0 {
60 struct i2c_client *client;
61 struct i2c_client *i2c_bl;
62 bool in_bootloader;
63 u8 bl_version;
64 struct completion complete;
65 struct device *dev;
66 unsigned long flags;
67 const char *fw_name;
68 struct ucsi *ucsi;
69 bool suspended;
70 bool wakeup_event;
71};
72
73/*
74 * Bootloader commands helpers:
75 * - send command (2 bytes)
76 * - check ack
77 * Then either:
78 * - receive data
79 * - receive data + check ack
80 * - send data + check ack
81 * These operations depends on the command and have various length.
82 */
83static int ucsi_stm32g0_bl_check_ack(struct ucsi *ucsi)
84{
85 struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
86 struct i2c_client *client = g0->i2c_bl;
87 unsigned char ack;
88 struct i2c_msg msg[] = {
89 {
90 .addr = client->addr,
91 .flags = I2C_M_RD,
92 .len = 1,
93 .buf = &ack,
94 },
95 };
96 int ret;
97
98 ret = i2c_transfer(adap: client->adapter, msgs: msg, ARRAY_SIZE(msg));
99 if (ret != ARRAY_SIZE(msg)) {
100 dev_err(g0->dev, "i2c bl ack (%02x), error: %d\n", client->addr, ret);
101
102 return ret < 0 ? ret : -EIO;
103 }
104
105 /* The 'ack' byte should contain bootloader answer: ack/nack/busy */
106 switch (ack) {
107 case STM32G0_I2C_BL_ACK:
108 return 0;
109 case STM32G0_I2C_BL_NACK:
110 return -ENOENT;
111 case STM32G0_I2C_BL_BUSY:
112 return -EBUSY;
113 default:
114 dev_err(g0->dev, "i2c bl ack (%02x), invalid byte: %02x\n",
115 client->addr, ack);
116 return -EINVAL;
117 }
118}
119
120static int ucsi_stm32g0_bl_cmd_check_ack(struct ucsi *ucsi, unsigned int cmd, bool check_ack)
121{
122 struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
123 struct i2c_client *client = g0->i2c_bl;
124 unsigned char buf[2];
125 struct i2c_msg msg[] = {
126 {
127 .addr = client->addr,
128 .flags = 0,
129 .len = sizeof(buf),
130 .buf = buf,
131 },
132 };
133 int ret;
134
135 /*
136 * Send STM32 bootloader command format is two bytes:
137 * - command code
138 * - XOR'ed command code
139 */
140 buf[0] = cmd;
141 buf[1] = cmd ^ 0xff;
142
143 ret = i2c_transfer(adap: client->adapter, msgs: msg, ARRAY_SIZE(msg));
144 if (ret != ARRAY_SIZE(msg)) {
145 dev_dbg(g0->dev, "i2c bl cmd %d (%02x), error: %d\n", cmd, client->addr, ret);
146
147 return ret < 0 ? ret : -EIO;
148 }
149
150 if (check_ack)
151 return ucsi_stm32g0_bl_check_ack(ucsi);
152
153 return 0;
154}
155
156static int ucsi_stm32g0_bl_cmd(struct ucsi *ucsi, unsigned int cmd)
157{
158 return ucsi_stm32g0_bl_cmd_check_ack(ucsi, cmd, check_ack: true);
159}
160
161static int ucsi_stm32g0_bl_rcv_check_ack(struct ucsi *ucsi, void *data, size_t len, bool check_ack)
162{
163 struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
164 struct i2c_client *client = g0->i2c_bl;
165 struct i2c_msg msg[] = {
166 {
167 .addr = client->addr,
168 .flags = I2C_M_RD,
169 .len = len,
170 .buf = data,
171 },
172 };
173 int ret;
174
175 ret = i2c_transfer(adap: client->adapter, msgs: msg, ARRAY_SIZE(msg));
176 if (ret != ARRAY_SIZE(msg)) {
177 dev_err(g0->dev, "i2c bl rcv %02x, error: %d\n", client->addr, ret);
178
179 return ret < 0 ? ret : -EIO;
180 }
181
182 if (check_ack)
183 return ucsi_stm32g0_bl_check_ack(ucsi);
184
185 return 0;
186}
187
188static int ucsi_stm32g0_bl_rcv(struct ucsi *ucsi, void *data, size_t len)
189{
190 return ucsi_stm32g0_bl_rcv_check_ack(ucsi, data, len, check_ack: true);
191}
192
193static int ucsi_stm32g0_bl_rcv_woack(struct ucsi *ucsi, void *data, size_t len)
194{
195 return ucsi_stm32g0_bl_rcv_check_ack(ucsi, data, len, check_ack: false);
196}
197
198static int ucsi_stm32g0_bl_send(struct ucsi *ucsi, void *data, size_t len)
199{
200 struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
201 struct i2c_client *client = g0->i2c_bl;
202 struct i2c_msg msg[] = {
203 {
204 .addr = client->addr,
205 .flags = 0,
206 .len = len,
207 .buf = data,
208 },
209 };
210 int ret;
211
212 ret = i2c_transfer(adap: client->adapter, msgs: msg, ARRAY_SIZE(msg));
213 if (ret != ARRAY_SIZE(msg)) {
214 dev_err(g0->dev, "i2c bl send %02x, error: %d\n", client->addr, ret);
215
216 return ret < 0 ? ret : -EIO;
217 }
218
219 return ucsi_stm32g0_bl_check_ack(ucsi);
220}
221
222/* Bootloader commands */
223static int ucsi_stm32g0_bl_get_version(struct ucsi *ucsi, u8 *bl_version)
224{
225 int ret;
226
227 ret = ucsi_stm32g0_bl_cmd(ucsi, STM32_CMD_GVR);
228 if (ret)
229 return ret;
230
231 return ucsi_stm32g0_bl_rcv(ucsi, data: bl_version, STM32_CMD_GVR_LEN);
232}
233
234static int ucsi_stm32g0_bl_send_addr(struct ucsi *ucsi, u32 addr)
235{
236 u8 data8[STM32_CMD_ADDR_LEN];
237
238 /* Address format: 4 bytes addr (MSB first) + XOR'ed addr bytes */
239 put_unaligned_be32(val: addr, p: data8);
240 data8[4] = data8[0] ^ data8[1] ^ data8[2] ^ data8[3];
241
242 return ucsi_stm32g0_bl_send(ucsi, data: data8, STM32_CMD_ADDR_LEN);
243}
244
245static int ucsi_stm32g0_bl_global_mass_erase(struct ucsi *ucsi)
246{
247 u8 data8[4];
248 u16 *data16 = (u16 *)&data8[0];
249 int ret;
250
251 data16[0] = STM32_CMD_GLOBAL_MASS_ERASE;
252 data8[2] = data8[0] ^ data8[1];
253
254 ret = ucsi_stm32g0_bl_cmd(ucsi, STM32_CMD_ERASE);
255 if (ret)
256 return ret;
257
258 return ucsi_stm32g0_bl_send(ucsi, data: data8, STM32_CMD_ERASE_SPECIAL_LEN);
259}
260
261static int ucsi_stm32g0_bl_write(struct ucsi *ucsi, u32 addr, const void *data, size_t len)
262{
263 u8 *data8;
264 int i, ret;
265
266 if (!len || len > STM32G0_I2C_BL_SZ)
267 return -EINVAL;
268
269 /* Write memory: len bytes -1, data up to 256 bytes + XOR'ed bytes */
270 data8 = kmalloc(STM32G0_I2C_BL_SZ + 2, GFP_KERNEL);
271 if (!data8)
272 return -ENOMEM;
273
274 ret = ucsi_stm32g0_bl_cmd(ucsi, STM32_CMD_WM);
275 if (ret)
276 goto free;
277
278 ret = ucsi_stm32g0_bl_send_addr(ucsi, addr);
279 if (ret)
280 goto free;
281
282 data8[0] = len - 1;
283 memcpy(data8 + 1, data, len);
284 data8[len + 1] = data8[0];
285 for (i = 1; i <= len; i++)
286 data8[len + 1] ^= data8[i];
287
288 ret = ucsi_stm32g0_bl_send(ucsi, data: data8, len: len + 2);
289free:
290 kfree(objp: data8);
291
292 return ret;
293}
294
295static int ucsi_stm32g0_bl_read(struct ucsi *ucsi, u32 addr, void *data, size_t len)
296{
297 int ret;
298
299 if (!len || len > STM32G0_I2C_BL_SZ)
300 return -EINVAL;
301
302 ret = ucsi_stm32g0_bl_cmd(ucsi, STM32_CMD_RM);
303 if (ret)
304 return ret;
305
306 ret = ucsi_stm32g0_bl_send_addr(ucsi, addr);
307 if (ret)
308 return ret;
309
310 ret = ucsi_stm32g0_bl_cmd(ucsi, cmd: len - 1);
311 if (ret)
312 return ret;
313
314 return ucsi_stm32g0_bl_rcv_woack(ucsi, data, len);
315}
316
317/* Firmware commands (the same address as the bootloader) */
318static int ucsi_stm32g0_fw_cmd(struct ucsi *ucsi, unsigned int cmd)
319{
320 return ucsi_stm32g0_bl_cmd_check_ack(ucsi, cmd, check_ack: false);
321}
322
323static int ucsi_stm32g0_fw_rcv(struct ucsi *ucsi, void *data, size_t len)
324{
325 return ucsi_stm32g0_bl_rcv_woack(ucsi, data, len);
326}
327
328/* UCSI ops */
329static int ucsi_stm32g0_read(struct ucsi *ucsi, unsigned int offset, void *val, size_t len)
330{
331 struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
332 struct i2c_client *client = g0->client;
333 u8 reg = offset;
334 struct i2c_msg msg[] = {
335 {
336 .addr = client->addr,
337 .flags = 0,
338 .len = 1,
339 .buf = &reg,
340 },
341 {
342 .addr = client->addr,
343 .flags = I2C_M_RD,
344 .len = len,
345 .buf = val,
346 },
347 };
348 int ret;
349
350 ret = i2c_transfer(adap: client->adapter, msgs: msg, ARRAY_SIZE(msg));
351 if (ret != ARRAY_SIZE(msg)) {
352 dev_err(g0->dev, "i2c read %02x, %02x error: %d\n", client->addr, reg, ret);
353
354 return ret < 0 ? ret : -EIO;
355 }
356
357 return 0;
358}
359
360static int ucsi_stm32g0_async_write(struct ucsi *ucsi, unsigned int offset, const void *val,
361 size_t len)
362{
363 struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
364 struct i2c_client *client = g0->client;
365 struct i2c_msg msg[] = {
366 {
367 .addr = client->addr,
368 .flags = 0,
369 }
370 };
371 unsigned char *buf;
372 int ret;
373
374 buf = kmalloc(size: len + 1, GFP_KERNEL);
375 if (!buf)
376 return -ENOMEM;
377
378 buf[0] = offset;
379 memcpy(&buf[1], val, len);
380 msg[0].len = len + 1;
381 msg[0].buf = buf;
382
383 ret = i2c_transfer(adap: client->adapter, msgs: msg, ARRAY_SIZE(msg));
384 kfree(objp: buf);
385 if (ret != ARRAY_SIZE(msg)) {
386 dev_err(g0->dev, "i2c write %02x, %02x error: %d\n", client->addr, offset, ret);
387
388 return ret < 0 ? ret : -EIO;
389 }
390
391 return 0;
392}
393
394static int ucsi_stm32g0_sync_write(struct ucsi *ucsi, unsigned int offset, const void *val,
395 size_t len)
396{
397 struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
398 int ret;
399
400 set_bit(COMMAND_PENDING, addr: &g0->flags);
401
402 ret = ucsi_stm32g0_async_write(ucsi, offset, val, len);
403 if (ret)
404 goto out_clear_bit;
405
406 if (!wait_for_completion_timeout(x: &g0->complete, timeout: msecs_to_jiffies(m: 5000)))
407 ret = -ETIMEDOUT;
408
409out_clear_bit:
410 clear_bit(COMMAND_PENDING, addr: &g0->flags);
411
412 return ret;
413}
414
415static irqreturn_t ucsi_stm32g0_irq_handler(int irq, void *data)
416{
417 struct ucsi_stm32g0 *g0 = data;
418 u32 cci;
419 int ret;
420
421 if (g0->suspended)
422 g0->wakeup_event = true;
423
424 ret = ucsi_stm32g0_read(ucsi: g0->ucsi, UCSI_CCI, val: &cci, len: sizeof(cci));
425 if (ret)
426 return IRQ_NONE;
427
428 if (UCSI_CCI_CONNECTOR(cci))
429 ucsi_connector_change(ucsi: g0->ucsi, UCSI_CCI_CONNECTOR(cci));
430
431 if (test_bit(COMMAND_PENDING, &g0->flags) &&
432 cci & (UCSI_CCI_ACK_COMPLETE | UCSI_CCI_COMMAND_COMPLETE))
433 complete(&g0->complete);
434
435 return IRQ_HANDLED;
436}
437
438static const struct ucsi_operations ucsi_stm32g0_ops = {
439 .read = ucsi_stm32g0_read,
440 .sync_write = ucsi_stm32g0_sync_write,
441 .async_write = ucsi_stm32g0_async_write,
442};
443
444static int ucsi_stm32g0_register(struct ucsi *ucsi)
445{
446 struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
447 struct i2c_client *client = g0->client;
448 int ret;
449
450 /* Request alert interrupt */
451 ret = request_threaded_irq(irq: client->irq, NULL, thread_fn: ucsi_stm32g0_irq_handler, IRQF_ONESHOT,
452 name: dev_name(dev: g0->dev), dev: g0);
453 if (ret) {
454 dev_err(g0->dev, "request IRQ failed: %d\n", ret);
455 return ret;
456 }
457
458 ret = ucsi_register(ucsi);
459 if (ret) {
460 dev_err_probe(dev: g0->dev, err: ret, fmt: "ucsi_register failed\n");
461 free_irq(client->irq, g0);
462 return ret;
463 }
464
465 return 0;
466}
467
468static void ucsi_stm32g0_unregister(struct ucsi *ucsi)
469{
470 struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
471 struct i2c_client *client = g0->client;
472
473 ucsi_unregister(ucsi);
474 free_irq(client->irq, g0);
475}
476
477static void ucsi_stm32g0_fw_cb(const struct firmware *fw, void *context)
478{
479 struct ucsi_stm32g0 *g0;
480 const u8 *data, *end;
481 const struct ucsi_stm32g0_fw_info *fw_info;
482 u32 addr = STM32G0_MAIN_MEM_ADDR, ob, fw_version;
483 int ret, size;
484
485 if (!context)
486 return;
487
488 g0 = ucsi_get_drvdata(ucsi: context);
489
490 if (!fw)
491 goto fw_release;
492
493 fw_info = (struct ucsi_stm32g0_fw_info *)(fw->data + fw->size - sizeof(*fw_info));
494
495 if (!g0->in_bootloader) {
496 /* Read running firmware version */
497 ret = ucsi_stm32g0_fw_cmd(ucsi: g0->ucsi, STM32G0_FW_GETVER);
498 if (ret) {
499 dev_err(g0->dev, "Get version cmd failed %d\n", ret);
500 goto fw_release;
501 }
502 ret = ucsi_stm32g0_fw_rcv(ucsi: g0->ucsi, data: &fw_version,
503 STM32G0_FW_GETVER_LEN);
504 if (ret) {
505 dev_err(g0->dev, "Get version failed %d\n", ret);
506 goto fw_release;
507 }
508
509 /* Sanity check on keyword and firmware version */
510 if (fw_info->keyword != STM32G0_FW_KEYWORD || fw_info->version == fw_version)
511 goto fw_release;
512
513 dev_info(g0->dev, "Flashing FW: %08x (%08x cur)\n", fw_info->version, fw_version);
514
515 /* Switch to bootloader mode */
516 ucsi_stm32g0_unregister(ucsi: g0->ucsi);
517 ret = ucsi_stm32g0_fw_cmd(ucsi: g0->ucsi, STM32G0_FW_RSTGOBL);
518 if (ret) {
519 dev_err(g0->dev, "bootloader cmd failed %d\n", ret);
520 goto fw_release;
521 }
522 g0->in_bootloader = true;
523
524 /* STM32G0 reboot delay */
525 msleep(msecs: 100);
526 }
527
528 ret = ucsi_stm32g0_bl_global_mass_erase(ucsi: g0->ucsi);
529 if (ret) {
530 dev_err(g0->dev, "Erase failed %d\n", ret);
531 goto fw_release;
532 }
533
534 data = fw->data;
535 end = fw->data + fw->size;
536 while (data < end) {
537 if ((end - data) < STM32G0_I2C_BL_SZ)
538 size = end - data;
539 else
540 size = STM32G0_I2C_BL_SZ;
541
542 ret = ucsi_stm32g0_bl_write(ucsi: g0->ucsi, addr, data, len: size);
543 if (ret) {
544 dev_err(g0->dev, "Write failed %d\n", ret);
545 goto fw_release;
546 }
547 addr += size;
548 data += size;
549 }
550
551 dev_dbg(g0->dev, "Configure to boot from main flash\n");
552
553 ret = ucsi_stm32g0_bl_read(ucsi: g0->ucsi, STM32G0_USER_OPTION_BYTES, data: &ob, len: sizeof(ob));
554 if (ret) {
555 dev_err(g0->dev, "read user option bytes failed %d\n", ret);
556 goto fw_release;
557 }
558
559 dev_dbg(g0->dev, "STM32G0_USER_OPTION_BYTES 0x%08x\n", ob);
560
561 /* Configure user option bytes to boot from main flash next time */
562 ob |= STM32G0_USER_OB_BOOT_MAIN;
563
564 /* Writing option bytes will also reset G0 for updates to be loaded */
565 ret = ucsi_stm32g0_bl_write(ucsi: g0->ucsi, STM32G0_USER_OPTION_BYTES, data: &ob, len: sizeof(ob));
566 if (ret) {
567 dev_err(g0->dev, "write user option bytes failed %d\n", ret);
568 goto fw_release;
569 }
570
571 dev_info(g0->dev, "Starting, option bytes:0x%08x\n", ob);
572
573 /* STM32G0 FW boot delay */
574 msleep(msecs: 500);
575
576 /* Register UCSI interface */
577 if (!ucsi_stm32g0_register(ucsi: g0->ucsi))
578 g0->in_bootloader = false;
579
580fw_release:
581 release_firmware(fw);
582}
583
584static int ucsi_stm32g0_probe_bootloader(struct ucsi *ucsi)
585{
586 struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
587 int ret;
588 u16 ucsi_version;
589
590 /* firmware-name is optional */
591 if (device_property_present(dev: g0->dev, propname: "firmware-name")) {
592 ret = device_property_read_string(dev: g0->dev, propname: "firmware-name", val: &g0->fw_name);
593 if (ret < 0)
594 return dev_err_probe(dev: g0->dev, err: ret, fmt: "Error reading firmware-name\n");
595 }
596
597 if (g0->fw_name) {
598 /* STM32G0 in bootloader mode communicates at reserved address 0x51 */
599 g0->i2c_bl = i2c_new_dummy_device(adapter: g0->client->adapter, STM32G0_I2C_BL_ADDR);
600 if (IS_ERR(ptr: g0->i2c_bl)) {
601 ret = dev_err_probe(dev: g0->dev, err: PTR_ERR(ptr: g0->i2c_bl),
602 fmt: "Failed to register bootloader I2C address\n");
603 return ret;
604 }
605 }
606
607 /*
608 * Try to guess if the STM32G0 is running a UCSI firmware. First probe the UCSI FW at its
609 * i2c address. Fallback to bootloader i2c address only if firmware-name is specified.
610 */
611 ret = ucsi_stm32g0_read(ucsi, UCSI_VERSION, val: &ucsi_version, len: sizeof(ucsi_version));
612 if (!ret || !g0->fw_name)
613 return ret;
614
615 /* Speculatively read the bootloader version that has a known length. */
616 ret = ucsi_stm32g0_bl_get_version(ucsi, bl_version: &g0->bl_version);
617 if (ret < 0) {
618 i2c_unregister_device(client: g0->i2c_bl);
619 return ret;
620 }
621
622 /* Device in bootloader mode */
623 g0->in_bootloader = true;
624 dev_info(g0->dev, "Bootloader Version 0x%02x\n", g0->bl_version);
625
626 return 0;
627}
628
629static int ucsi_stm32g0_probe(struct i2c_client *client)
630{
631 struct device *dev = &client->dev;
632 struct ucsi_stm32g0 *g0;
633 int ret;
634
635 g0 = devm_kzalloc(dev, size: sizeof(*g0), GFP_KERNEL);
636 if (!g0)
637 return -ENOMEM;
638
639 g0->dev = dev;
640 g0->client = client;
641 init_completion(x: &g0->complete);
642 i2c_set_clientdata(client, data: g0);
643
644 g0->ucsi = ucsi_create(dev, ops: &ucsi_stm32g0_ops);
645 if (IS_ERR(ptr: g0->ucsi))
646 return PTR_ERR(ptr: g0->ucsi);
647
648 ucsi_set_drvdata(ucsi: g0->ucsi, data: g0);
649
650 ret = ucsi_stm32g0_probe_bootloader(ucsi: g0->ucsi);
651 if (ret < 0)
652 goto destroy;
653
654 /*
655 * Don't register in bootloader mode: wait for the firmware to be loaded and started before
656 * registering UCSI device.
657 */
658 if (!g0->in_bootloader) {
659 ret = ucsi_stm32g0_register(ucsi: g0->ucsi);
660 if (ret < 0)
661 goto freei2c;
662 }
663
664 if (g0->fw_name) {
665 /*
666 * Asynchronously flash (e.g. bootloader mode) or update the running firmware,
667 * not to hang the boot process
668 */
669 ret = request_firmware_nowait(THIS_MODULE, FW_ACTION_UEVENT, name: g0->fw_name, device: g0->dev,
670 GFP_KERNEL, context: g0->ucsi, cont: ucsi_stm32g0_fw_cb);
671 if (ret < 0) {
672 dev_err_probe(dev, err: ret, fmt: "firmware request failed\n");
673 goto unregister;
674 }
675 }
676
677 return 0;
678
679unregister:
680 if (!g0->in_bootloader)
681 ucsi_stm32g0_unregister(ucsi: g0->ucsi);
682freei2c:
683 if (g0->fw_name)
684 i2c_unregister_device(client: g0->i2c_bl);
685destroy:
686 ucsi_destroy(ucsi: g0->ucsi);
687
688 return ret;
689}
690
691static void ucsi_stm32g0_remove(struct i2c_client *client)
692{
693 struct ucsi_stm32g0 *g0 = i2c_get_clientdata(client);
694
695 if (!g0->in_bootloader)
696 ucsi_stm32g0_unregister(ucsi: g0->ucsi);
697 if (g0->fw_name)
698 i2c_unregister_device(client: g0->i2c_bl);
699 ucsi_destroy(ucsi: g0->ucsi);
700}
701
702static int ucsi_stm32g0_suspend(struct device *dev)
703{
704 struct ucsi_stm32g0 *g0 = dev_get_drvdata(dev);
705 struct i2c_client *client = g0->client;
706
707 if (g0->in_bootloader)
708 return 0;
709
710 /* Keep the interrupt disabled until the i2c bus has been resumed */
711 disable_irq(irq: client->irq);
712
713 g0->suspended = true;
714 g0->wakeup_event = false;
715
716 if (device_may_wakeup(dev) || device_wakeup_path(dev))
717 enable_irq_wake(irq: client->irq);
718
719 return 0;
720}
721
722static int ucsi_stm32g0_resume(struct device *dev)
723{
724 struct ucsi_stm32g0 *g0 = dev_get_drvdata(dev);
725 struct i2c_client *client = g0->client;
726
727 if (g0->in_bootloader)
728 return 0;
729
730 if (device_may_wakeup(dev) || device_wakeup_path(dev))
731 disable_irq_wake(irq: client->irq);
732
733 enable_irq(irq: client->irq);
734
735 /* Enforce any pending handler gets called to signal a wakeup_event */
736 synchronize_irq(irq: client->irq);
737
738 if (g0->wakeup_event)
739 pm_wakeup_event(dev: g0->dev, msec: 0);
740
741 g0->suspended = false;
742
743 return 0;
744}
745
746static DEFINE_SIMPLE_DEV_PM_OPS(ucsi_stm32g0_pm_ops, ucsi_stm32g0_suspend, ucsi_stm32g0_resume);
747
748static const struct of_device_id __maybe_unused ucsi_stm32g0_typec_of_match[] = {
749 { .compatible = "st,stm32g0-typec" },
750 {},
751};
752MODULE_DEVICE_TABLE(of, ucsi_stm32g0_typec_of_match);
753
754static const struct i2c_device_id ucsi_stm32g0_typec_i2c_devid[] = {
755 {"stm32g0-typec", 0},
756 {},
757};
758MODULE_DEVICE_TABLE(i2c, ucsi_stm32g0_typec_i2c_devid);
759
760static struct i2c_driver ucsi_stm32g0_i2c_driver = {
761 .driver = {
762 .name = "ucsi-stm32g0-i2c",
763 .of_match_table = of_match_ptr(ucsi_stm32g0_typec_of_match),
764 .pm = pm_sleep_ptr(&ucsi_stm32g0_pm_ops),
765 },
766 .probe = ucsi_stm32g0_probe,
767 .remove = ucsi_stm32g0_remove,
768 .id_table = ucsi_stm32g0_typec_i2c_devid
769};
770module_i2c_driver(ucsi_stm32g0_i2c_driver);
771
772MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@foss.st.com>");
773MODULE_DESCRIPTION("STMicroelectronics STM32G0 Type-C controller");
774MODULE_LICENSE("Dual BSD/GPL");
775MODULE_ALIAS("platform:ucsi-stm32g0");
776

source code of linux/drivers/usb/typec/ucsi/ucsi_stm32g0.c