netfilter: nft_compat: narrow down revision to unsigned 8-bits
[platform/kernel/linux-rpi.git] / drivers / extcon / extcon-usbc-tusb320.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * drivers/extcon/extcon-tusb320.c - TUSB320 extcon driver
4  *
5  * Copyright (C) 2020 National Instruments Corporation
6  * Author: Michael Auchter <michael.auchter@ni.com>
7  */
8
9 #include <linux/bitfield.h>
10 #include <linux/extcon-provider.h>
11 #include <linux/i2c.h>
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/regmap.h>
17 #include <linux/usb/typec.h>
18 #include <linux/usb/typec_altmode.h>
19 #include <linux/usb/role.h>
20
21 #define TUSB320_REG8                            0x8
22 #define TUSB320_REG8_CURRENT_MODE_ADVERTISE     GENMASK(7, 6)
23 #define TUSB320_REG8_CURRENT_MODE_ADVERTISE_USB 0x0
24 #define TUSB320_REG8_CURRENT_MODE_ADVERTISE_15A 0x1
25 #define TUSB320_REG8_CURRENT_MODE_ADVERTISE_30A 0x2
26 #define TUSB320_REG8_CURRENT_MODE_DETECT        GENMASK(5, 4)
27 #define TUSB320_REG8_CURRENT_MODE_DETECT_DEF    0x0
28 #define TUSB320_REG8_CURRENT_MODE_DETECT_MED    0x1
29 #define TUSB320_REG8_CURRENT_MODE_DETECT_ACC    0x2
30 #define TUSB320_REG8_CURRENT_MODE_DETECT_HI     0x3
31 #define TUSB320_REG8_ACCESSORY_CONNECTED        GENMASK(3, 1)
32 #define TUSB320_REG8_ACCESSORY_CONNECTED_NONE   0x0
33 #define TUSB320_REG8_ACCESSORY_CONNECTED_AUDIO  0x4
34 #define TUSB320_REG8_ACCESSORY_CONNECTED_ACHRG  0x5
35 #define TUSB320_REG8_ACCESSORY_CONNECTED_DBGDFP 0x6
36 #define TUSB320_REG8_ACCESSORY_CONNECTED_DBGUFP 0x7
37 #define TUSB320_REG8_ACTIVE_CABLE_DETECTION     BIT(0)
38
39 #define TUSB320_REG9                            0x9
40 #define TUSB320_REG9_ATTACHED_STATE             GENMASK(7, 6)
41 #define TUSB320_REG9_CABLE_DIRECTION            BIT(5)
42 #define TUSB320_REG9_INTERRUPT_STATUS           BIT(4)
43
44 #define TUSB320_REGA                            0xa
45 #define TUSB320L_REGA_DISABLE_TERM              BIT(0)
46 #define TUSB320_REGA_I2C_SOFT_RESET             BIT(3)
47 #define TUSB320_REGA_MODE_SELECT_SHIFT          4
48 #define TUSB320_REGA_MODE_SELECT_MASK           0x3
49
50 #define TUSB320L_REGA0_REVISION                 0xa0
51
52 enum tusb320_attached_state {
53         TUSB320_ATTACHED_STATE_NONE,
54         TUSB320_ATTACHED_STATE_DFP,
55         TUSB320_ATTACHED_STATE_UFP,
56         TUSB320_ATTACHED_STATE_ACC,
57 };
58
59 enum tusb320_mode {
60         TUSB320_MODE_PORT,
61         TUSB320_MODE_UFP,
62         TUSB320_MODE_DFP,
63         TUSB320_MODE_DRP,
64 };
65
66 struct tusb320_priv;
67
68 struct tusb320_ops {
69         int (*set_mode)(struct tusb320_priv *priv, enum tusb320_mode mode);
70         int (*get_revision)(struct tusb320_priv *priv, unsigned int *revision);
71 };
72
73 struct tusb320_priv {
74         struct device *dev;
75         struct regmap *regmap;
76         struct extcon_dev *edev;
77         struct tusb320_ops *ops;
78         enum tusb320_attached_state state;
79         struct typec_port *port;
80         struct typec_capability cap;
81         enum typec_port_type port_type;
82         enum typec_pwr_opmode pwr_opmode;
83         struct fwnode_handle *connector_fwnode;
84         struct usb_role_switch *role_sw;
85 };
86
87 static const char * const tusb_attached_states[] = {
88         [TUSB320_ATTACHED_STATE_NONE] = "not attached",
89         [TUSB320_ATTACHED_STATE_DFP]  = "downstream facing port",
90         [TUSB320_ATTACHED_STATE_UFP]  = "upstream facing port",
91         [TUSB320_ATTACHED_STATE_ACC]  = "accessory",
92 };
93
94 static const unsigned int tusb320_extcon_cable[] = {
95         EXTCON_USB,
96         EXTCON_USB_HOST,
97         EXTCON_NONE,
98 };
99
100 static int tusb320_check_signature(struct tusb320_priv *priv)
101 {
102         static const char sig[] = { '\0', 'T', 'U', 'S', 'B', '3', '2', '0' };
103         unsigned val;
104         int i, ret;
105
106         for (i = 0; i < sizeof(sig); i++) {
107                 ret = regmap_read(priv->regmap, sizeof(sig) - 1 - i, &val);
108                 if (ret < 0)
109                         return ret;
110                 if (val != sig[i]) {
111                         dev_err(priv->dev, "signature mismatch!\n");
112                         return -ENODEV;
113                 }
114         }
115
116         return 0;
117 }
118
119 static int tusb320_set_mode(struct tusb320_priv *priv, enum tusb320_mode mode)
120 {
121         int ret;
122
123         /* Mode cannot be changed while cable is attached */
124         if (priv->state != TUSB320_ATTACHED_STATE_NONE)
125                 return -EBUSY;
126
127         /* Write mode */
128         ret = regmap_write_bits(priv->regmap, TUSB320_REGA,
129                 TUSB320_REGA_MODE_SELECT_MASK << TUSB320_REGA_MODE_SELECT_SHIFT,
130                 mode << TUSB320_REGA_MODE_SELECT_SHIFT);
131         if (ret) {
132                 dev_err(priv->dev, "failed to write mode: %d\n", ret);
133                 return ret;
134         }
135
136         return 0;
137 }
138
139 static int tusb320l_set_mode(struct tusb320_priv *priv, enum tusb320_mode mode)
140 {
141         int ret;
142
143         /* Disable CC state machine */
144         ret = regmap_write_bits(priv->regmap, TUSB320_REGA,
145                 TUSB320L_REGA_DISABLE_TERM, 1);
146         if (ret) {
147                 dev_err(priv->dev,
148                         "failed to disable CC state machine: %d\n", ret);
149                 return ret;
150         }
151
152         /* Write mode */
153         ret = regmap_write_bits(priv->regmap, TUSB320_REGA,
154                 TUSB320_REGA_MODE_SELECT_MASK << TUSB320_REGA_MODE_SELECT_SHIFT,
155                 mode << TUSB320_REGA_MODE_SELECT_SHIFT);
156         if (ret) {
157                 dev_err(priv->dev, "failed to write mode: %d\n", ret);
158                 goto err;
159         }
160
161         msleep(5);
162 err:
163         /* Re-enable CC state machine */
164         ret = regmap_write_bits(priv->regmap, TUSB320_REGA,
165                 TUSB320L_REGA_DISABLE_TERM, 0);
166         if (ret)
167                 dev_err(priv->dev,
168                         "failed to re-enable CC state machine: %d\n", ret);
169
170         return ret;
171 }
172
173 static int tusb320_reset(struct tusb320_priv *priv)
174 {
175         int ret;
176
177         /* Set mode to default (follow PORT pin) */
178         ret = priv->ops->set_mode(priv, TUSB320_MODE_PORT);
179         if (ret && ret != -EBUSY) {
180                 dev_err(priv->dev,
181                         "failed to set mode to PORT: %d\n", ret);
182                 return ret;
183         }
184
185         /* Perform soft reset */
186         ret = regmap_write_bits(priv->regmap, TUSB320_REGA,
187                         TUSB320_REGA_I2C_SOFT_RESET, 1);
188         if (ret) {
189                 dev_err(priv->dev,
190                         "failed to write soft reset bit: %d\n", ret);
191                 return ret;
192         }
193
194         /* Wait for chip to go through reset */
195         msleep(95);
196
197         return 0;
198 }
199
200 static int tusb320l_get_revision(struct tusb320_priv *priv, unsigned int *revision)
201 {
202         return regmap_read(priv->regmap, TUSB320L_REGA0_REVISION, revision);
203 }
204
205 static struct tusb320_ops tusb320_ops = {
206         .set_mode = tusb320_set_mode,
207 };
208
209 static struct tusb320_ops tusb320l_ops = {
210         .set_mode = tusb320l_set_mode,
211         .get_revision = tusb320l_get_revision,
212 };
213
214 static int tusb320_set_adv_pwr_mode(struct tusb320_priv *priv)
215 {
216         u8 mode;
217
218         if (priv->pwr_opmode == TYPEC_PWR_MODE_USB)
219                 mode = TUSB320_REG8_CURRENT_MODE_ADVERTISE_USB;
220         else if (priv->pwr_opmode == TYPEC_PWR_MODE_1_5A)
221                 mode = TUSB320_REG8_CURRENT_MODE_ADVERTISE_15A;
222         else if (priv->pwr_opmode == TYPEC_PWR_MODE_3_0A)
223                 mode = TUSB320_REG8_CURRENT_MODE_ADVERTISE_30A;
224         else    /* No other mode is supported. */
225                 return -EINVAL;
226
227         return regmap_write_bits(priv->regmap, TUSB320_REG8,
228                                  TUSB320_REG8_CURRENT_MODE_ADVERTISE,
229                                  FIELD_PREP(TUSB320_REG8_CURRENT_MODE_ADVERTISE,
230                                             mode));
231 }
232
233 static int tusb320_port_type_set(struct typec_port *port,
234                                  enum typec_port_type type)
235 {
236         struct tusb320_priv *priv = typec_get_drvdata(port);
237
238         if (type == TYPEC_PORT_SRC)
239                 return priv->ops->set_mode(priv, TUSB320_MODE_DFP);
240         else if (type == TYPEC_PORT_SNK)
241                 return priv->ops->set_mode(priv, TUSB320_MODE_UFP);
242         else if (type == TYPEC_PORT_DRP)
243                 return priv->ops->set_mode(priv, TUSB320_MODE_DRP);
244         else
245                 return priv->ops->set_mode(priv, TUSB320_MODE_PORT);
246 }
247
248 static const struct typec_operations tusb320_typec_ops = {
249         .port_type_set  = tusb320_port_type_set,
250 };
251
252 static void tusb320_extcon_irq_handler(struct tusb320_priv *priv, u8 reg)
253 {
254         int state, polarity;
255
256         state = FIELD_GET(TUSB320_REG9_ATTACHED_STATE, reg);
257         polarity = !!(reg & TUSB320_REG9_CABLE_DIRECTION);
258
259         dev_dbg(priv->dev, "attached state: %s, polarity: %d\n",
260                 tusb_attached_states[state], polarity);
261
262         extcon_set_state(priv->edev, EXTCON_USB,
263                          state == TUSB320_ATTACHED_STATE_UFP);
264         extcon_set_state(priv->edev, EXTCON_USB_HOST,
265                          state == TUSB320_ATTACHED_STATE_DFP);
266         extcon_set_property(priv->edev, EXTCON_USB,
267                             EXTCON_PROP_USB_TYPEC_POLARITY,
268                             (union extcon_property_value)polarity);
269         extcon_set_property(priv->edev, EXTCON_USB_HOST,
270                             EXTCON_PROP_USB_TYPEC_POLARITY,
271                             (union extcon_property_value)polarity);
272         extcon_sync(priv->edev, EXTCON_USB);
273         extcon_sync(priv->edev, EXTCON_USB_HOST);
274
275         priv->state = state;
276 }
277
278 static void tusb320_typec_irq_handler(struct tusb320_priv *priv, u8 reg9)
279 {
280         struct typec_port *port = priv->port;
281         struct device *dev = priv->dev;
282         int typec_mode;
283         enum usb_role usb_role;
284         enum typec_role pwr_role;
285         enum typec_data_role data_role;
286         u8 state, mode, accessory;
287         int ret, reg8;
288         bool ori;
289
290         ret = regmap_read(priv->regmap, TUSB320_REG8, &reg8);
291         if (ret) {
292                 dev_err(dev, "error during reg8 i2c read, ret=%d!\n", ret);
293                 return;
294         }
295
296         ori = reg9 & TUSB320_REG9_CABLE_DIRECTION;
297         typec_set_orientation(port, ori ? TYPEC_ORIENTATION_REVERSE :
298                                           TYPEC_ORIENTATION_NORMAL);
299
300         state = FIELD_GET(TUSB320_REG9_ATTACHED_STATE, reg9);
301         accessory = FIELD_GET(TUSB320_REG8_ACCESSORY_CONNECTED, reg8);
302
303         switch (state) {
304         case TUSB320_ATTACHED_STATE_DFP:
305                 typec_mode = TYPEC_MODE_USB2;
306                 usb_role = USB_ROLE_HOST;
307                 pwr_role = TYPEC_SOURCE;
308                 data_role = TYPEC_HOST;
309                 break;
310         case TUSB320_ATTACHED_STATE_UFP:
311                 typec_mode = TYPEC_MODE_USB2;
312                 usb_role = USB_ROLE_DEVICE;
313                 pwr_role = TYPEC_SINK;
314                 data_role = TYPEC_DEVICE;
315                 break;
316         case TUSB320_ATTACHED_STATE_ACC:
317                 /*
318                  * Accessory detected. For debug accessories, just make some
319                  * qualified guesses as to the role for lack of a better option.
320                  */
321                 if (accessory == TUSB320_REG8_ACCESSORY_CONNECTED_AUDIO ||
322                     accessory == TUSB320_REG8_ACCESSORY_CONNECTED_ACHRG) {
323                         typec_mode = TYPEC_MODE_AUDIO;
324                         usb_role = USB_ROLE_NONE;
325                         pwr_role = TYPEC_SINK;
326                         data_role = TYPEC_DEVICE;
327                         break;
328                 } else if (accessory ==
329                            TUSB320_REG8_ACCESSORY_CONNECTED_DBGDFP) {
330                         typec_mode = TYPEC_MODE_DEBUG;
331                         pwr_role = TYPEC_SOURCE;
332                         usb_role = USB_ROLE_HOST;
333                         data_role = TYPEC_HOST;
334                         break;
335                 } else if (accessory ==
336                            TUSB320_REG8_ACCESSORY_CONNECTED_DBGUFP) {
337                         typec_mode = TYPEC_MODE_DEBUG;
338                         pwr_role = TYPEC_SINK;
339                         usb_role = USB_ROLE_DEVICE;
340                         data_role = TYPEC_DEVICE;
341                         break;
342                 }
343
344                 dev_warn(priv->dev, "unexpected ACCESSORY_CONNECTED state %d\n",
345                          accessory);
346
347                 fallthrough;
348         default:
349                 typec_mode = TYPEC_MODE_USB2;
350                 usb_role = USB_ROLE_NONE;
351                 pwr_role = TYPEC_SINK;
352                 data_role = TYPEC_DEVICE;
353                 break;
354         }
355
356         typec_set_vconn_role(port, pwr_role);
357         typec_set_pwr_role(port, pwr_role);
358         typec_set_data_role(port, data_role);
359         typec_set_mode(port, typec_mode);
360         usb_role_switch_set_role(priv->role_sw, usb_role);
361
362         mode = FIELD_GET(TUSB320_REG8_CURRENT_MODE_DETECT, reg8);
363         if (mode == TUSB320_REG8_CURRENT_MODE_DETECT_DEF)
364                 typec_set_pwr_opmode(port, TYPEC_PWR_MODE_USB);
365         else if (mode == TUSB320_REG8_CURRENT_MODE_DETECT_MED)
366                 typec_set_pwr_opmode(port, TYPEC_PWR_MODE_1_5A);
367         else if (mode == TUSB320_REG8_CURRENT_MODE_DETECT_HI)
368                 typec_set_pwr_opmode(port, TYPEC_PWR_MODE_3_0A);
369         else    /* Charge through accessory */
370                 typec_set_pwr_opmode(port, TYPEC_PWR_MODE_USB);
371 }
372
373 static irqreturn_t tusb320_state_update_handler(struct tusb320_priv *priv,
374                                                 bool force_update)
375 {
376         unsigned int reg;
377
378         if (regmap_read(priv->regmap, TUSB320_REG9, &reg)) {
379                 dev_err(priv->dev, "error during i2c read!\n");
380                 return IRQ_NONE;
381         }
382
383         if (!force_update && !(reg & TUSB320_REG9_INTERRUPT_STATUS))
384                 return IRQ_NONE;
385
386         tusb320_extcon_irq_handler(priv, reg);
387
388         /*
389          * Type-C support is optional. Only call the Type-C handler if a
390          * port had been registered previously.
391          */
392         if (priv->port)
393                 tusb320_typec_irq_handler(priv, reg);
394
395         regmap_write(priv->regmap, TUSB320_REG9, reg);
396
397         return IRQ_HANDLED;
398 }
399
400 static irqreturn_t tusb320_irq_handler(int irq, void *dev_id)
401 {
402         struct tusb320_priv *priv = dev_id;
403
404         return tusb320_state_update_handler(priv, false);
405 }
406
407 static const struct regmap_config tusb320_regmap_config = {
408         .reg_bits = 8,
409         .val_bits = 8,
410 };
411
412 static int tusb320_extcon_probe(struct tusb320_priv *priv)
413 {
414         int ret;
415
416         priv->edev = devm_extcon_dev_allocate(priv->dev, tusb320_extcon_cable);
417         if (IS_ERR(priv->edev)) {
418                 dev_err(priv->dev, "failed to allocate extcon device\n");
419                 return PTR_ERR(priv->edev);
420         }
421
422         ret = devm_extcon_dev_register(priv->dev, priv->edev);
423         if (ret < 0) {
424                 dev_err(priv->dev, "failed to register extcon device\n");
425                 return ret;
426         }
427
428         extcon_set_property_capability(priv->edev, EXTCON_USB,
429                                        EXTCON_PROP_USB_TYPEC_POLARITY);
430         extcon_set_property_capability(priv->edev, EXTCON_USB_HOST,
431                                        EXTCON_PROP_USB_TYPEC_POLARITY);
432
433         return 0;
434 }
435
436 static int tusb320_typec_probe(struct i2c_client *client,
437                                struct tusb320_priv *priv)
438 {
439         struct fwnode_handle *connector;
440         const char *cap_str;
441         int ret;
442
443         /* The Type-C connector is optional, for backward compatibility. */
444         connector = device_get_named_child_node(&client->dev, "connector");
445         if (!connector)
446                 return 0;
447
448         /* Type-C connector found. */
449         ret = typec_get_fw_cap(&priv->cap, connector);
450         if (ret)
451                 goto err_put;
452
453         priv->port_type = priv->cap.type;
454
455         /* This goes into register 0x8 field CURRENT_MODE_ADVERTISE */
456         ret = fwnode_property_read_string(connector, "typec-power-opmode", &cap_str);
457         if (ret)
458                 goto err_put;
459
460         ret = typec_find_pwr_opmode(cap_str);
461         if (ret < 0)
462                 goto err_put;
463
464         priv->pwr_opmode = ret;
465
466         /* Initialize the hardware with the devicetree settings. */
467         ret = tusb320_set_adv_pwr_mode(priv);
468         if (ret)
469                 goto err_put;
470
471         priv->cap.revision              = USB_TYPEC_REV_1_1;
472         priv->cap.accessory[0]          = TYPEC_ACCESSORY_AUDIO;
473         priv->cap.accessory[1]          = TYPEC_ACCESSORY_DEBUG;
474         priv->cap.orientation_aware     = true;
475         priv->cap.driver_data           = priv;
476         priv->cap.ops                   = &tusb320_typec_ops;
477         priv->cap.fwnode                = connector;
478
479         priv->port = typec_register_port(&client->dev, &priv->cap);
480         if (IS_ERR(priv->port)) {
481                 ret = PTR_ERR(priv->port);
482                 goto err_put;
483         }
484
485         /* Find any optional USB role switch that needs reporting to */
486         priv->role_sw = fwnode_usb_role_switch_get(connector);
487         if (IS_ERR(priv->role_sw)) {
488                 ret = PTR_ERR(priv->role_sw);
489                 goto err_unreg;
490         }
491
492         priv->connector_fwnode = connector;
493
494         return 0;
495
496 err_unreg:
497         typec_unregister_port(priv->port);
498
499 err_put:
500         fwnode_handle_put(connector);
501
502         return ret;
503 }
504
505 static void tusb320_typec_remove(struct tusb320_priv *priv)
506 {
507         usb_role_switch_put(priv->role_sw);
508         typec_unregister_port(priv->port);
509         fwnode_handle_put(priv->connector_fwnode);
510 }
511
512 static int tusb320_probe(struct i2c_client *client)
513 {
514         struct tusb320_priv *priv;
515         const void *match_data;
516         unsigned int revision;
517         int ret;
518
519         priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);
520         if (!priv)
521                 return -ENOMEM;
522
523         priv->dev = &client->dev;
524         i2c_set_clientdata(client, priv);
525
526         priv->regmap = devm_regmap_init_i2c(client, &tusb320_regmap_config);
527         if (IS_ERR(priv->regmap))
528                 return PTR_ERR(priv->regmap);
529
530         ret = tusb320_check_signature(priv);
531         if (ret)
532                 return ret;
533
534         match_data = device_get_match_data(&client->dev);
535         if (!match_data)
536                 return -EINVAL;
537
538         priv->ops = (struct tusb320_ops*)match_data;
539
540         if (priv->ops->get_revision) {
541                 ret = priv->ops->get_revision(priv, &revision);
542                 if (ret)
543                         dev_warn(priv->dev,
544                                 "failed to read revision register: %d\n", ret);
545                 else
546                         dev_info(priv->dev, "chip revision %d\n", revision);
547         }
548
549         ret = tusb320_extcon_probe(priv);
550         if (ret)
551                 return ret;
552
553         ret = tusb320_typec_probe(client, priv);
554         if (ret)
555                 return ret;
556
557         /* update initial state */
558         tusb320_state_update_handler(priv, true);
559
560         /* Reset chip to its default state */
561         ret = tusb320_reset(priv);
562         if (ret)
563                 dev_warn(priv->dev, "failed to reset chip: %d\n", ret);
564         else
565                 /*
566                  * State and polarity might change after a reset, so update
567                  * them again and make sure the interrupt status bit is cleared.
568                  */
569                 tusb320_state_update_handler(priv, true);
570
571         ret = devm_request_threaded_irq(priv->dev, client->irq, NULL,
572                                         tusb320_irq_handler,
573                                         IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
574                                         client->name, priv);
575         if (ret)
576                 tusb320_typec_remove(priv);
577
578         return ret;
579 }
580
581 static void tusb320_remove(struct i2c_client *client)
582 {
583         struct tusb320_priv *priv = i2c_get_clientdata(client);
584
585         tusb320_typec_remove(priv);
586 }
587
588 static const struct of_device_id tusb320_extcon_dt_match[] = {
589         { .compatible = "ti,tusb320", .data = &tusb320_ops, },
590         { .compatible = "ti,tusb320l", .data = &tusb320l_ops, },
591         { }
592 };
593 MODULE_DEVICE_TABLE(of, tusb320_extcon_dt_match);
594
595 static struct i2c_driver tusb320_extcon_driver = {
596         .probe          = tusb320_probe,
597         .remove         = tusb320_remove,
598         .driver         = {
599                 .name   = "extcon-tusb320",
600                 .of_match_table = tusb320_extcon_dt_match,
601         },
602 };
603
604 static int __init tusb320_init(void)
605 {
606         return i2c_add_driver(&tusb320_extcon_driver);
607 }
608 subsys_initcall(tusb320_init);
609
610 static void __exit tusb320_exit(void)
611 {
612         i2c_del_driver(&tusb320_extcon_driver);
613 }
614 module_exit(tusb320_exit);
615
616 MODULE_AUTHOR("Michael Auchter <michael.auchter@ni.com>");
617 MODULE_DESCRIPTION("TI TUSB320 extcon driver");
618 MODULE_LICENSE("GPL v2");