drivers/usb/typec/mux/ptn36502.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * NXP PTN36502 Type-C driver
   4  *
   5  * Copyright (C) 2023 Luca Weiss <[email protected]>
   6  *
   7  * Based on NB7VPQ904M driver:
   8  * Copyright (C) 2023 Dmitry Baryshkov <[email protected]>
   9  */
  10
  11 #include <drm/bridge/aux-bridge.h>
  12 #include <linux/bitfield.h>
  13 #include <linux/i2c.h>
  14 #include <linux/kernel.h>
  15 #include <linux/module.h>
  16 #include <linux/mutex.h>
  17 #include <linux/of_graph.h>
  18 #include <linux/regmap.h>
  19 #include <linux/regulator/consumer.h>
  20 #include <linux/usb/typec_dp.h>
  21 #include <linux/usb/typec_mux.h>
  22 #include <linux/usb/typec_retimer.h>
  23
  24 #define PTN36502_CHIP_ID_REG                            0x00
  25 #define PTN36502_CHIP_ID                                0x02
  26
  27 #define PTN36502_CHIP_REVISION_REG                      0x01
  28 #define PTN36502_CHIP_REVISION_BASE_MASK                GENMASK(7, 4)
  29 #define PTN36502_CHIP_REVISION_METAL_MASK               GENMASK(3, 0)
  30
  31 #define PTN36502_DP_LINK_CTRL_REG                       0x06
  32 #define PTN36502_DP_LINK_CTRL_LANES_MASK                GENMASK(3, 2)
  33 #define PTN36502_DP_LINK_CTRL_LANES_2                   (2)
  34 #define PTN36502_DP_LINK_CTRL_LANES_4                   (3)
  35 #define PTN36502_DP_LINK_CTRL_LINK_RATE_MASK            GENMASK(1, 0)
  36 #define PTN36502_DP_LINK_CTRL_LINK_RATE_5_4GBPS         (2)
  37
  38 /* Registers for lane 0 (0x07) to lane 3 (0x0a) have the same layout */
  39 #define PTN36502_DP_LANE_CTRL_REG(n)                    (0x07 + (n))
  40 #define PTN36502_DP_LANE_CTRL_RX_GAIN_MASK              GENMASK(6, 4)
  41 #define PTN36502_DP_LANE_CTRL_RX_GAIN_3DB               (2)
  42 #define PTN36502_DP_LANE_CTRL_TX_SWING_MASK             GENMASK(3, 2)
  43 #define PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD         (2)
  44 #define PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_MASK         GENMASK(1, 0)
  45 #define PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_3_5DB        (1)
  46
  47 #define PTN36502_MODE_CTRL1_REG                         0x0b
  48 #define PTN36502_MODE_CTRL1_PLUG_ORIENT_MASK            GENMASK(5, 5)
  49 #define PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE         (1)
  50 #define PTN36502_MODE_CTRL1_AUX_CROSSBAR_MASK           GENMASK(3, 3)
  51 #define PTN36502_MODE_CTRL1_AUX_CROSSBAR_SW_ON          (1)
  52 #define PTN36502_MODE_CTRL1_MODE_MASK                   GENMASK(2, 0)
  53 #define PTN36502_MODE_CTRL1_MODE_OFF                    (0)
  54 #define PTN36502_MODE_CTRL1_MODE_USB_ONLY               (1)
  55 #define PTN36502_MODE_CTRL1_MODE_USB_DP                 (2)
  56 #define PTN36502_MODE_CTRL1_MODE_DP                     (3)
  57
  58 #define PTN36502_DEVICE_CTRL_REG                        0x0d
  59 #define PTN36502_DEVICE_CTRL_AUX_MONITORING_MASK        GENMASK(7, 7)
  60 #define PTN36502_DEVICE_CTRL_AUX_MONITORING_EN          (1)
  61
  62 struct ptn36502 {
  63         struct i2c_client *client;
  64         struct regulator *vdd18_supply;
  65         struct regmap *regmap;
  66         struct typec_switch_dev *sw;
  67         struct typec_retimer *retimer;
  68
  69         struct typec_switch *typec_switch;
  70         struct typec_mux *typec_mux;
  71
  72         struct mutex lock; /* protect non-concurrent retimer & switch */
  73
  74         enum typec_orientation orientation;
  75         unsigned long mode;
  76         unsigned int svid;
  77 };
  78
  79 static int ptn36502_set(struct ptn36502 *ptn)
  80 {
  81         bool reverse = (ptn->orientation == TYPEC_ORIENTATION_REVERSE);
  82         unsigned int ctrl1_val = 0;
  83         unsigned int lane_ctrl_val = 0;
  84         unsigned int link_ctrl_val = 0;
  85
  86         switch (ptn->mode) {
  87         case TYPEC_STATE_SAFE:
  88                 /* Deep power saving state */
  89                 regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG,
  90                              FIELD_PREP(PTN36502_MODE_CTRL1_MODE_MASK,
  91                                         PTN36502_MODE_CTRL1_MODE_OFF));
  92                 return 0;
  93
  94         case TYPEC_STATE_USB:
  95                 /*
  96                  * Normal Orientation (CC1)
  97                  * A -> USB RX
  98                  * B -> USB TX
  99                  * C -> X
 100                  * D -> X
 101                  * Flipped Orientation (CC2)
 102                  * A -> X
 103                  * B -> X
 104                  * C -> USB TX
 105                  * D -> USB RX
 106                  */
 107
 108                 /* USB 3.1 Gen 1 only */
 109                 ctrl1_val = FIELD_PREP(PTN36502_MODE_CTRL1_MODE_MASK,
 110                                        PTN36502_MODE_CTRL1_MODE_USB_ONLY);
 111                 if (reverse)
 112                         ctrl1_val |= FIELD_PREP(PTN36502_MODE_CTRL1_PLUG_ORIENT_MASK,
 113                                                 PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE);
 114
 115                 regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG, ctrl1_val);
 116                 return 0;
 117
 118         default:
 119                 if (ptn->svid != USB_TYPEC_DP_SID)
 120                         return -EINVAL;
 121
 122                 break;
 123         }
 124
 125         /* DP Altmode Setup */
 126
 127         switch (ptn->mode) {
 128         case TYPEC_DP_STATE_C:
 129         case TYPEC_DP_STATE_E:
 130                 /*
 131                  * Normal Orientation (CC1)
 132                  * A -> DP3
 133                  * B -> DP2
 134                  * C -> DP1
 135                  * D -> DP0
 136                  * Flipped Orientation (CC2)
 137                  * A -> DP0
 138                  * B -> DP1
 139                  * C -> DP2
 140                  * D -> DP3
 141                  */
 142
 143                 /* 4-lane DP */
 144                 ctrl1_val |= FIELD_PREP(PTN36502_MODE_CTRL1_MODE_MASK,
 145                                         PTN36502_MODE_CTRL1_MODE_DP);
 146                 link_ctrl_val |= FIELD_PREP(PTN36502_DP_LINK_CTRL_LANES_MASK,
 147                                             PTN36502_DP_LINK_CTRL_LANES_4);
 148                 break;
 149
 150         case TYPEC_DP_STATE_D:
 151         case TYPEC_DP_STATE_F: /* State F is deprecated */
 152                 /*
 153                  * Normal Orientation (CC1)
 154                  * A -> USB RX
 155                  * B -> USB TX
 156                  * C -> DP1
 157                  * D -> DP0
 158                  * Flipped Orientation (CC2)
 159                  * A -> DP0
 160                  * B -> DP1
 161                  * C -> USB TX
 162                  * D -> USB RX
 163                  */
 164
 165                 /* USB 3.1 Gen 1 and 2-lane DP */
 166                 ctrl1_val |= FIELD_PREP(PTN36502_MODE_CTRL1_MODE_MASK,
 167                                         PTN36502_MODE_CTRL1_MODE_USB_DP);
 168                 link_ctrl_val |= FIELD_PREP(PTN36502_DP_LINK_CTRL_LANES_MASK,
 169                                             PTN36502_DP_LINK_CTRL_LANES_2);
 170                 break;
 171
 172         default:
 173                 return -EOPNOTSUPP;
 174         }
 175
 176         /* Enable AUX monitoring */
 177         regmap_write(ptn->regmap, PTN36502_DEVICE_CTRL_REG,
 178                      FIELD_PREP(PTN36502_DEVICE_CTRL_AUX_MONITORING_MASK,
 179                                 PTN36502_DEVICE_CTRL_AUX_MONITORING_EN));
 180
 181         /* Enable AUX switch path */
 182         ctrl1_val |= FIELD_PREP(PTN36502_MODE_CTRL1_AUX_CROSSBAR_MASK,
 183                                 PTN36502_MODE_CTRL1_AUX_CROSSBAR_SW_ON);
 184         if (reverse)
 185                 ctrl1_val |= FIELD_PREP(PTN36502_MODE_CTRL1_PLUG_ORIENT_MASK,
 186                                         PTN36502_MODE_CTRL1_PLUG_ORIENT_REVERSE);
 187         regmap_write(ptn->regmap, PTN36502_MODE_CTRL1_REG, ctrl1_val);
 188
 189         /* DP Link rate: 5.4 Gbps (HBR2) */
 190         link_ctrl_val |= FIELD_PREP(PTN36502_DP_LINK_CTRL_LINK_RATE_MASK,
 191                                     PTN36502_DP_LINK_CTRL_LINK_RATE_5_4GBPS);
 192         regmap_write(ptn->regmap, PTN36502_DP_LINK_CTRL_REG, link_ctrl_val);
 193
 194         /*
 195          * For all lanes:
 196          * - Rx equivalization gain: 3 dB
 197          * - TX output swing control: 800 mVppd
 198          * - Pre-emphasis control: 3.5 dB
 199          */
 200         lane_ctrl_val = FIELD_PREP(PTN36502_DP_LANE_CTRL_RX_GAIN_MASK,
 201                                    PTN36502_DP_LANE_CTRL_RX_GAIN_3DB) |
 202                         FIELD_PREP(PTN36502_DP_LANE_CTRL_TX_SWING_MASK,
 203                                    PTN36502_DP_LANE_CTRL_TX_SWING_800MVPPD) |
 204                         FIELD_PREP(PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_MASK,
 205                                    PTN36502_DP_LANE_CTRL_PRE_EMPHASIS_3_5DB);
 206         regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(0), lane_ctrl_val);
 207         regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(1), lane_ctrl_val);
 208         regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(2), lane_ctrl_val);
 209         regmap_write(ptn->regmap, PTN36502_DP_LANE_CTRL_REG(3), lane_ctrl_val);
 210
 211         return 0;
 212 }
 213
 214 static int ptn36502_sw_set(struct typec_switch_dev *sw, enum typec_orientation orientation)
 215 {
 216         struct ptn36502 *ptn = typec_switch_get_drvdata(sw);
 217         int ret;
 218
 219         ret = typec_switch_set(ptn->typec_switch, orientation);
 220         if (ret)
 221                 return ret;
 222
 223         mutex_lock(&ptn->lock);
 224
 225         if (ptn->orientation != orientation) {
 226                 ptn->orientation = orientation;
 227
 228                 ret = ptn36502_set(ptn);
 229         }
 230
 231         mutex_unlock(&ptn->lock);
 232
 233         return ret;
 234 }
 235
 236 static int ptn36502_retimer_set(struct typec_retimer *retimer, struct typec_retimer_state *state)
 237 {
 238         struct ptn36502 *ptn = typec_retimer_get_drvdata(retimer);
 239         struct typec_mux_state mux_state;
 240         int ret = 0;
 241
 242         mutex_lock(&ptn->lock);
 243
 244         if (ptn->mode != state->mode) {
 245                 ptn->mode = state->mode;
 246
 247                 if (state->alt)
 248                         ptn->svid = state->alt->svid;
 249                 else
 250                         ptn->svid = 0; // No SVID
 251
 252                 ret = ptn36502_set(ptn);
 253         }
 254
 255         mutex_unlock(&ptn->lock);
 256
 257         if (ret)
 258                 return ret;
 259
 260         mux_state.alt = state->alt;
 261         mux_state.data = state->data;
 262         mux_state.mode = state->mode;
 263
 264         return typec_mux_set(ptn->typec_mux, &mux_state);
 265 }
 266
 267 static int ptn36502_detect(struct ptn36502 *ptn)
 268 {
 269         struct device *dev = &ptn->client->dev;
 270         unsigned int reg_val;
 271         int ret;
 272
 273         ret = regmap_read(ptn->regmap, PTN36502_CHIP_ID_REG,
 274                           &reg_val);
 275         if (ret < 0)
 276                 return dev_err_probe(dev, ret, "Failed to read chip ID\n");
 277
 278         if (reg_val != PTN36502_CHIP_ID)
 279                 return dev_err_probe(dev, -ENODEV, "Unexpected chip ID: %x\n", reg_val);
 280
 281         ret = regmap_read(ptn->regmap, PTN36502_CHIP_REVISION_REG,
 282                           &reg_val);
 283         if (ret < 0)
 284                 return dev_err_probe(dev, ret, "Failed to read chip revision\n");
 285
 286         dev_dbg(dev, "Chip revision: base layer version %lx, metal layer version %lx\n",
 287                 FIELD_GET(PTN36502_CHIP_REVISION_BASE_MASK, reg_val),
 288                 FIELD_GET(PTN36502_CHIP_REVISION_METAL_MASK, reg_val));
 289
 290         return 0;
 291 }
 292
 293 static const struct regmap_config ptn36502_regmap = {
 294         .max_register = 0x0d,
 295         .reg_bits = 8,
 296         .val_bits = 8,
 297 };
 298
 299 static int ptn36502_probe(struct i2c_client *client)
 300 {
 301         struct device *dev = &client->dev;
 302         struct typec_switch_desc sw_desc = { };
 303         struct typec_retimer_desc retimer_desc = { };
 304         struct ptn36502 *ptn;
 305         int ret;
 306
 307         ptn = devm_kzalloc(dev, sizeof(*ptn), GFP_KERNEL);
 308         if (!ptn)
 309                 return -ENOMEM;
 310
 311         ptn->client = client;
 312
 313         ptn->regmap = devm_regmap_init_i2c(client, &ptn36502_regmap);
 314         if (IS_ERR(ptn->regmap)) {
 315                 dev_err(&client->dev, "Failed to allocate register map\n");
 316                 return PTR_ERR(ptn->regmap);
 317         }
 318
 319         ptn->mode = TYPEC_STATE_SAFE;
 320         ptn->orientation = TYPEC_ORIENTATION_NONE;
 321
 322         mutex_init(&ptn->lock);
 323
 324         ptn->vdd18_supply = devm_regulator_get_optional(dev, "vdd18");
 325         if (IS_ERR(ptn->vdd18_supply))
 326                 return PTR_ERR(ptn->vdd18_supply);
 327
 328         ptn->typec_switch = fwnode_typec_switch_get(dev->fwnode);
 329         if (IS_ERR(ptn->typec_switch))
 330                 return dev_err_probe(dev, PTR_ERR(ptn->typec_switch),
 331                                      "Failed to acquire orientation-switch\n");
 332
 333         ptn->typec_mux = fwnode_typec_mux_get(dev->fwnode);
 334         if (IS_ERR(ptn->typec_mux)) {
 335                 ret = dev_err_probe(dev, PTR_ERR(ptn->typec_mux),
 336                                     "Failed to acquire mode-switch\n");
 337                 goto err_switch_put;
 338         }
 339
 340         ret = regulator_enable(ptn->vdd18_supply);
 341         if (ret) {
 342                 ret = dev_err_probe(dev, ret, "Failed to enable vdd18\n");
 343                 goto err_mux_put;
 344         }
 345
 346         ret = ptn36502_detect(ptn);
 347         if (ret)
 348                 goto err_disable_regulator;
 349
 350         ret = drm_aux_bridge_register(dev);
 351         if (ret)
 352                 goto err_disable_regulator;
 353
 354         sw_desc.drvdata = ptn;
 355         sw_desc.fwnode = dev->fwnode;
 356         sw_desc.set = ptn36502_sw_set;
 357
 358         ptn->sw = typec_switch_register(dev, &sw_desc);
 359         if (IS_ERR(ptn->sw)) {
 360                 ret = dev_err_probe(dev, PTR_ERR(ptn->sw),
 361                                     "Failed to register typec switch\n");
 362                 goto err_disable_regulator;
 363         }
 364
 365         retimer_desc.drvdata = ptn;
 366         retimer_desc.fwnode = dev->fwnode;
 367         retimer_desc.set = ptn36502_retimer_set;
 368
 369         ptn->retimer = typec_retimer_register(dev, &retimer_desc);
 370         if (IS_ERR(ptn->retimer)) {
 371                 ret = dev_err_probe(dev, PTR_ERR(ptn->retimer),
 372                                     "Failed to register typec retimer\n");
 373                 goto err_switch_unregister;
 374         }
 375
 376         return 0;
 377
 378 err_switch_unregister:
 379         typec_switch_unregister(ptn->sw);
 380
 381 err_disable_regulator:
 382         regulator_disable(ptn->vdd18_supply);
 383
 384 err_mux_put:
 385         typec_mux_put(ptn->typec_mux);
 386
 387 err_switch_put:
 388         typec_switch_put(ptn->typec_switch);
 389
 390         return ret;
 391 }
 392
 393 static void ptn36502_remove(struct i2c_client *client)
 394 {
 395         struct ptn36502 *ptn = i2c_get_clientdata(client);
 396
 397         typec_retimer_unregister(ptn->retimer);
 398         typec_switch_unregister(ptn->sw);
 399
 400         regulator_disable(ptn->vdd18_supply);
 401
 402         typec_mux_put(ptn->typec_mux);
 403         typec_switch_put(ptn->typec_switch);
 404 }
 405
 406 static const struct i2c_device_id ptn36502_table[] = {
 407         { "ptn36502" },
 408         { }
 409 };
 410 MODULE_DEVICE_TABLE(i2c, ptn36502_table);
 411
 412 static const struct of_device_id ptn36502_of_table[] = {
 413         { .compatible = "nxp,ptn36502" },
 414         { }
 415 };
 416 MODULE_DEVICE_TABLE(of, ptn36502_of_table);
 417
 418 static struct i2c_driver ptn36502_driver = {
 419         .driver = {
 420                 .name = "ptn36502",
 421                 .of_match_table = ptn36502_of_table,
 422         },
 423         .probe          = ptn36502_probe,
 424         .remove         = ptn36502_remove,
 425         .id_table       = ptn36502_table,
 426 };
 427 module_i2c_driver(ptn36502_driver);
 428
 429 MODULE_AUTHOR("Luca Weiss <[email protected]>");
 430 MODULE_DESCRIPTION("NXP PTN36502 Type-C driver");
 431 MODULE_LICENSE("GPL");