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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * ON Semiconductor LC824206XA Micro USB Switch driver4 *5 * Copyright (c) 2024 Hans de Goede <hansg@kernel.org>6 *7 * ON Semiconductor has an "Advance Information" datasheet available8 * (ENA2222-D.PDF), but no full datasheet. So there is no documentation9 * available for the registers.10 *11 * This driver is based on the register info from the extcon-fsa9285.c driver,12 * from the Lollipop Android sources for the Lenovo Yoga Tablet 2 (Pro)13 * 830 / 1050 / 1380 models. Note despite the name this is actually a driver14 * for the LC824206XA not the FSA9285. The Android sources can be downloaded15 * from Lenovo's support page for these tablets, filename:16 * yoga_tab_2_osc_android_to_lollipop_201505.rar.17 */18 19#include <linux/bits.h>20#include <linux/delay.h>21#include <linux/device.h>22#include <linux/extcon-provider.h>23#include <linux/i2c.h>24#include <linux/interrupt.h>25#include <linux/module.h>26#include <linux/power_supply.h>27#include <linux/property.h>28#include <linux/regulator/consumer.h>29#include <linux/workqueue.h>30 31/*32 * Register defines as mentioned above there is no datasheet with register33 * info, so this may not be 100% accurate.34 */35#define REG00 0x0036#define REG00_INIT_VALUE 0x0137 38#define REG_STATUS 0x0139#define STATUS_OVP BIT(0)40#define STATUS_DATA_SHORT BIT(1)41#define STATUS_VBUS_PRESENT BIT(2)42#define STATUS_USB_ID GENMASK(7, 3)43#define STATUS_USB_ID_GND 0x8044#define STATUS_USB_ID_ACA 0xf045#define STATUS_USB_ID_FLOAT 0xf846 47/*48 * This controls the DP/DM muxes + other switches,49 * meaning of individual bits is unknown.50 */51#define REG_SWITCH_CONTROL 0x0252#define SWITCH_STEREO_MIC 0xc853#define SWITCH_USB_HOST 0xec54#define SWITCH_DISCONNECTED 0xf855#define SWITCH_USB_DEVICE 0xfc56 57/* 5 bits? ADC 0x10 GND, 0x1a-0x1f ACA, 0x1f float */58#define REG_ID_PIN_ADC_VALUE 0x0359 60/* Masks for all 3 interrupt registers */61#define INTR_ID_PIN_CHANGE BIT(0)62#define INTR_VBUS_CHANGE BIT(1)63/* Both of these get set after a continuous mode ADC conversion */64#define INTR_ID_PIN_ADC_INT1 BIT(2)65#define INTR_ID_PIN_ADC_INT2 BIT(3)66/* Charger type available in reg 0x09 */67#define INTR_CHARGER_DET_DONE BIT(4)68#define INTR_OVP BIT(5)69 70/* There are 7 interrupt sources, bit 6 use is unknown (OCP?) */71#define INTR_ALL GENMASK(6, 0)72 73/* Unmask interrupts this driver cares about */74#define INTR_MASK \75 (INTR_ALL & ~(INTR_ID_PIN_CHANGE | INTR_VBUS_CHANGE | INTR_CHARGER_DET_DONE))76 77/* Active (event happened and not cleared yet) interrupts */78#define REG_INTR_STATUS 0x0479 80/*81 * Writing a 1 to a bit here clears it in INTR_STATUS. These bits do NOT82 * auto-reset to 0, so these must be set to 0 manually after clearing.83 */84#define REG_INTR_CLEAR 0x0585 86/* Interrupts which bit is set to 1 here will not raise the HW IRQ */87#define REG_INTR_MASK 0x0688 89/* ID pin ADC control, meaning of individual bits is unknown */90#define REG_ID_PIN_ADC_CTRL 0x0791#define ID_PIN_ADC_AUTO 0x4092#define ID_PIN_ADC_CONTINUOUS 0x4493 94#define REG_CHARGER_DET 0x0895#define CHARGER_DET_ON BIT(0)96#define CHARGER_DET_CDP_ON BIT(1)97#define CHARGER_DET_CDP_VAL BIT(2)98 99#define REG_CHARGER_TYPE 0x09100#define CHARGER_TYPE_UNKNOWN 0x00101#define CHARGER_TYPE_DCP 0x01102#define CHARGER_TYPE_SDP_OR_CDP 0x04103#define CHARGER_TYPE_QC 0x06104 105#define REG10 0x10106#define REG10_INIT_VALUE 0x00107 108struct lc824206xa_data {109 struct work_struct work;110 struct i2c_client *client;111 struct extcon_dev *edev;112 struct power_supply *psy;113 struct regulator *vbus_boost;114 unsigned int usb_type;115 unsigned int cable;116 unsigned int previous_cable;117 u8 switch_control;118 u8 previous_switch_control;119 bool vbus_ok;120 bool vbus_boost_enabled;121 bool fastcharge_over_miclr;122};123 124static const unsigned int lc824206xa_cables[] = {125 EXTCON_USB_HOST,126 EXTCON_CHG_USB_SDP,127 EXTCON_CHG_USB_CDP,128 EXTCON_CHG_USB_DCP,129 EXTCON_CHG_USB_ACA,130 EXTCON_CHG_USB_FAST,131 EXTCON_NONE,132};133 134/* read/write reg helpers to add error logging to smbus byte functions */135static int lc824206xa_read_reg(struct lc824206xa_data *data, u8 reg)136{137 int ret;138 139 ret = i2c_smbus_read_byte_data(data->client, reg);140 if (ret < 0)141 dev_err(&data->client->dev, "Error %d reading reg 0x%02x\n", ret, reg);142 143 return ret;144}145 146static int lc824206xa_write_reg(struct lc824206xa_data *data, u8 reg, u8 val)147{148 int ret;149 150 ret = i2c_smbus_write_byte_data(data->client, reg, val);151 if (ret < 0)152 dev_err(&data->client->dev, "Error %d writing reg 0x%02x\n", ret, reg);153 154 return ret;155}156 157static int lc824206xa_get_id(struct lc824206xa_data *data)158{159 int ret;160 161 ret = lc824206xa_write_reg(data, REG_ID_PIN_ADC_CTRL, ID_PIN_ADC_CONTINUOUS);162 if (ret)163 return ret;164 165 ret = lc824206xa_read_reg(data, REG_ID_PIN_ADC_VALUE);166 167 lc824206xa_write_reg(data, REG_ID_PIN_ADC_CTRL, ID_PIN_ADC_AUTO);168 169 return ret;170}171 172static void lc824206xa_set_vbus_boost(struct lc824206xa_data *data, bool enable)173{174 int ret;175 176 if (data->vbus_boost_enabled == enable)177 return;178 179 if (enable)180 ret = regulator_enable(data->vbus_boost);181 else182 ret = regulator_disable(data->vbus_boost);183 184 if (ret == 0)185 data->vbus_boost_enabled = enable;186 else187 dev_err(&data->client->dev, "Error updating Vbus boost regulator: %d\n", ret);188}189 190static void lc824206xa_charger_detect(struct lc824206xa_data *data)191{192 int charger_type, ret;193 194 charger_type = lc824206xa_read_reg(data, REG_CHARGER_TYPE);195 if (charger_type < 0)196 return;197 198 dev_dbg(&data->client->dev, "charger type 0x%02x\n", charger_type);199 200 switch (charger_type) {201 case CHARGER_TYPE_UNKNOWN:202 data->usb_type = POWER_SUPPLY_USB_TYPE_UNKNOWN;203 /* Treat as SDP */204 data->cable = EXTCON_CHG_USB_SDP;205 data->switch_control = SWITCH_USB_DEVICE;206 break;207 case CHARGER_TYPE_SDP_OR_CDP:208 data->usb_type = POWER_SUPPLY_USB_TYPE_SDP;209 data->cable = EXTCON_CHG_USB_SDP;210 data->switch_control = SWITCH_USB_DEVICE;211 212 ret = lc824206xa_write_reg(data, REG_CHARGER_DET,213 CHARGER_DET_CDP_ON | CHARGER_DET_ON);214 if (ret < 0)215 break;216 217 msleep(100);218 ret = lc824206xa_read_reg(data, REG_CHARGER_DET);219 if (ret >= 0 && (ret & CHARGER_DET_CDP_VAL)) {220 data->usb_type = POWER_SUPPLY_USB_TYPE_CDP;221 data->cable = EXTCON_CHG_USB_CDP;222 }223 224 lc824206xa_write_reg(data, REG_CHARGER_DET, CHARGER_DET_ON);225 break;226 case CHARGER_TYPE_DCP:227 data->usb_type = POWER_SUPPLY_USB_TYPE_DCP;228 data->cable = EXTCON_CHG_USB_DCP;229 if (data->fastcharge_over_miclr)230 data->switch_control = SWITCH_STEREO_MIC;231 else232 data->switch_control = SWITCH_DISCONNECTED;233 break;234 case CHARGER_TYPE_QC:235 data->usb_type = POWER_SUPPLY_USB_TYPE_DCP;236 data->cable = EXTCON_CHG_USB_DCP;237 data->switch_control = SWITCH_DISCONNECTED;238 break;239 default:240 dev_warn(&data->client->dev, "Unknown charger type: 0x%02x\n", charger_type);241 break;242 }243}244 245static void lc824206xa_work(struct work_struct *work)246{247 struct lc824206xa_data *data = container_of(work, struct lc824206xa_data, work);248 bool vbus_boost_enable = false;249 int status, id;250 251 status = lc824206xa_read_reg(data, REG_STATUS);252 if (status < 0)253 return;254 255 dev_dbg(&data->client->dev, "status 0x%02x\n", status);256 257 data->vbus_ok = (status & (STATUS_VBUS_PRESENT | STATUS_OVP)) == STATUS_VBUS_PRESENT;258 259 /* Read id pin ADC if necessary */260 switch (status & STATUS_USB_ID) {261 case STATUS_USB_ID_GND:262 case STATUS_USB_ID_FLOAT:263 break;264 default:265 /* Happens when the connector is inserted slowly, log at dbg level */266 dev_dbg(&data->client->dev, "Unknown status 0x%02x\n", status);267 fallthrough;268 case STATUS_USB_ID_ACA:269 id = lc824206xa_get_id(data);270 dev_dbg(&data->client->dev, "RID 0x%02x\n", id);271 switch (id) {272 case 0x10:273 status = STATUS_USB_ID_GND;274 break;275 case 0x18 ... 0x1e:276 status = STATUS_USB_ID_ACA;277 break;278 case 0x1f:279 status = STATUS_USB_ID_FLOAT;280 break;281 default:282 dev_warn(&data->client->dev, "Unknown RID 0x%02x\n", id);283 return;284 }285 }286 287 /* Check for out of spec OTG charging hubs, treat as ACA */288 if ((status & STATUS_USB_ID) == STATUS_USB_ID_GND &&289 data->vbus_ok && !data->vbus_boost_enabled) {290 dev_info(&data->client->dev, "Out of spec USB host adapter with Vbus present, not enabling 5V output\n");291 status = STATUS_USB_ID_ACA;292 }293 294 switch (status & STATUS_USB_ID) {295 case STATUS_USB_ID_ACA:296 data->usb_type = POWER_SUPPLY_USB_TYPE_ACA;297 data->cable = EXTCON_CHG_USB_ACA;298 data->switch_control = SWITCH_USB_HOST;299 break;300 case STATUS_USB_ID_GND:301 data->usb_type = POWER_SUPPLY_USB_TYPE_UNKNOWN;302 data->cable = EXTCON_USB_HOST;303 data->switch_control = SWITCH_USB_HOST;304 vbus_boost_enable = true;305 break;306 case STATUS_USB_ID_FLOAT:307 /* When fast charging with Vbus > 5V, OVP will be set */308 if (data->fastcharge_over_miclr &&309 data->switch_control == SWITCH_STEREO_MIC &&310 (status & STATUS_OVP)) {311 data->cable = EXTCON_CHG_USB_FAST;312 break;313 }314 315 if (data->vbus_ok) {316 lc824206xa_charger_detect(data);317 } else {318 data->usb_type = POWER_SUPPLY_USB_TYPE_UNKNOWN;319 data->cable = EXTCON_NONE;320 data->switch_control = SWITCH_DISCONNECTED;321 }322 break;323 }324 325 lc824206xa_set_vbus_boost(data, vbus_boost_enable);326 327 if (data->switch_control != data->previous_switch_control) {328 lc824206xa_write_reg(data, REG_SWITCH_CONTROL, data->switch_control);329 data->previous_switch_control = data->switch_control;330 }331 332 if (data->cable != data->previous_cable) {333 extcon_set_state_sync(data->edev, data->previous_cable, false);334 extcon_set_state_sync(data->edev, data->cable, true);335 data->previous_cable = data->cable;336 }337 338 power_supply_changed(data->psy);339}340 341static irqreturn_t lc824206xa_irq(int irq, void *_data)342{343 struct lc824206xa_data *data = _data;344 int intr_status;345 346 intr_status = lc824206xa_read_reg(data, REG_INTR_STATUS);347 if (intr_status < 0)348 intr_status = INTR_ALL; /* Should never happen, clear all */349 350 dev_dbg(&data->client->dev, "interrupt 0x%02x\n", intr_status);351 352 lc824206xa_write_reg(data, REG_INTR_CLEAR, intr_status);353 lc824206xa_write_reg(data, REG_INTR_CLEAR, 0);354 355 schedule_work(&data->work);356 return IRQ_HANDLED;357}358 359/*360 * Newer charger (power_supply) drivers expect the max input current to be361 * provided by a parent power_supply device for the charger chip.362 */363static int lc824206xa_psy_get_prop(struct power_supply *psy,364 enum power_supply_property psp,365 union power_supply_propval *val)366{367 struct lc824206xa_data *data = power_supply_get_drvdata(psy);368 369 switch (psp) {370 case POWER_SUPPLY_PROP_ONLINE:371 val->intval = data->vbus_ok && !data->vbus_boost_enabled;372 break;373 case POWER_SUPPLY_PROP_USB_TYPE:374 val->intval = data->usb_type;375 break;376 case POWER_SUPPLY_PROP_CURRENT_MAX:377 switch (data->usb_type) {378 case POWER_SUPPLY_USB_TYPE_DCP:379 case POWER_SUPPLY_USB_TYPE_ACA:380 val->intval = 2000000;381 break;382 case POWER_SUPPLY_USB_TYPE_CDP:383 val->intval = 1500000;384 break;385 default:386 val->intval = 500000;387 }388 break;389 default:390 return -EINVAL;391 }392 393 return 0;394}395 396static const enum power_supply_property lc824206xa_psy_props[] = {397 POWER_SUPPLY_PROP_ONLINE,398 POWER_SUPPLY_PROP_USB_TYPE,399 POWER_SUPPLY_PROP_CURRENT_MAX,400};401 402static const struct power_supply_desc lc824206xa_psy_desc = {403 .name = "lc824206xa-charger-detect",404 .type = POWER_SUPPLY_TYPE_USB,405 .usb_types = BIT(POWER_SUPPLY_USB_TYPE_SDP) |406 BIT(POWER_SUPPLY_USB_TYPE_CDP) |407 BIT(POWER_SUPPLY_USB_TYPE_DCP) |408 BIT(POWER_SUPPLY_USB_TYPE_ACA) |409 BIT(POWER_SUPPLY_USB_TYPE_UNKNOWN),410 .properties = lc824206xa_psy_props,411 .num_properties = ARRAY_SIZE(lc824206xa_psy_props),412 .get_property = lc824206xa_psy_get_prop,413};414 415static int lc824206xa_probe(struct i2c_client *client)416{417 struct power_supply_config psy_cfg = { };418 struct device *dev = &client->dev;419 struct lc824206xa_data *data;420 int ret;421 422 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);423 if (!data)424 return -ENOMEM;425 426 data->client = client;427 INIT_WORK(&data->work, lc824206xa_work);428 data->cable = EXTCON_NONE;429 data->previous_cable = EXTCON_NONE;430 data->usb_type = POWER_SUPPLY_USB_TYPE_UNKNOWN;431 /* Some designs use a custom fast-charge protocol over the mic L/R inputs */432 data->fastcharge_over_miclr =433 device_property_read_bool(dev, "onnn,enable-miclr-for-dcp");434 435 data->vbus_boost = devm_regulator_get(dev, "vbus");436 if (IS_ERR(data->vbus_boost))437 return dev_err_probe(dev, PTR_ERR(data->vbus_boost),438 "getting regulator\n");439 440 /* Init */441 ret = lc824206xa_write_reg(data, REG00, REG00_INIT_VALUE);442 ret |= lc824206xa_write_reg(data, REG10, REG10_INIT_VALUE);443 msleep(100);444 ret |= lc824206xa_write_reg(data, REG_INTR_CLEAR, INTR_ALL);445 ret |= lc824206xa_write_reg(data, REG_INTR_CLEAR, 0);446 ret |= lc824206xa_write_reg(data, REG_INTR_MASK, INTR_MASK);447 ret |= lc824206xa_write_reg(data, REG_ID_PIN_ADC_CTRL, ID_PIN_ADC_AUTO);448 ret |= lc824206xa_write_reg(data, REG_CHARGER_DET, CHARGER_DET_ON);449 if (ret)450 return -EIO;451 452 /* Initialize extcon device */453 data->edev = devm_extcon_dev_allocate(dev, lc824206xa_cables);454 if (IS_ERR(data->edev))455 return PTR_ERR(data->edev);456 457 ret = devm_extcon_dev_register(dev, data->edev);458 if (ret)459 return dev_err_probe(dev, ret, "registering extcon device\n");460 461 psy_cfg.drv_data = data;462 data->psy = devm_power_supply_register(dev, &lc824206xa_psy_desc, &psy_cfg);463 if (IS_ERR(data->psy))464 return dev_err_probe(dev, PTR_ERR(data->psy), "registering power supply\n");465 466 ret = devm_request_threaded_irq(dev, client->irq, NULL, lc824206xa_irq,467 IRQF_TRIGGER_LOW | IRQF_ONESHOT,468 KBUILD_MODNAME, data);469 if (ret)470 return dev_err_probe(dev, ret, "requesting IRQ\n");471 472 /* Sync initial state */473 schedule_work(&data->work);474 return 0;475}476 477static const struct i2c_device_id lc824206xa_i2c_ids[] = {478 { "lc824206xa" },479 { }480};481MODULE_DEVICE_TABLE(i2c, lc824206xa_i2c_ids);482 483static struct i2c_driver lc824206xa_driver = {484 .driver = {485 .name = KBUILD_MODNAME,486 },487 .probe = lc824206xa_probe,488 .id_table = lc824206xa_i2c_ids,489};490 491module_i2c_driver(lc824206xa_driver);492 493MODULE_AUTHOR("Hans de Goede <hansg@kernel.org>");494MODULE_DESCRIPTION("LC824206XA Micro USB Switch driver");495MODULE_LICENSE("GPL");496