drivers/extcon/extcon-axp288.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * extcon-axp288.c - X-Power AXP288 PMIC extcon cable detection driver
   4  *
   5  * Copyright (c) 2017-2018 Hans de Goede <hdegoede@redhat.com>
   6  * Copyright (C) 2015 Intel Corporation
   7  * Author: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
   8  */
   9
  10 #include <linux/acpi.h>
  11 #include <linux/module.h>
  12 #include <linux/kernel.h>
  13 #include <linux/io.h>
  14 #include <linux/slab.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/property.h>
  18 #include <linux/notifier.h>
  19 #include <linux/extcon-provider.h>
  20 #include <linux/regmap.h>
  21 #include <linux/mfd/axp20x.h>
  22 #include <linux/usb/role.h>
  23 #include <linux/workqueue.h>
  24
  25 #include <asm/cpu_device_id.h>
  26 #include <asm/intel-family.h>
  27
  28 /* Power source status register */
  29 #define PS_STAT_VBUS_TRIGGER            BIT(0)
  30 #define PS_STAT_BAT_CHRG_DIR            BIT(2)
  31 #define PS_STAT_VBUS_ABOVE_VHOLD        BIT(3)
  32 #define PS_STAT_VBUS_VALID              BIT(4)
  33 #define PS_STAT_VBUS_PRESENT            BIT(5)
  34
  35 /* BC module global register */
  36 #define BC_GLOBAL_RUN                   BIT(0)
  37 #define BC_GLOBAL_DET_STAT              BIT(2)
  38 #define BC_GLOBAL_DBP_TOUT              BIT(3)
  39 #define BC_GLOBAL_VLGC_COM_SEL          BIT(4)
  40 #define BC_GLOBAL_DCD_TOUT_MASK         (BIT(6)|BIT(5))
  41 #define BC_GLOBAL_DCD_TOUT_300MS        0
  42 #define BC_GLOBAL_DCD_TOUT_100MS        1
  43 #define BC_GLOBAL_DCD_TOUT_500MS        2
  44 #define BC_GLOBAL_DCD_TOUT_900MS        3
  45 #define BC_GLOBAL_DCD_DET_SEL           BIT(7)
  46
  47 /* BC module vbus control and status register */
  48 #define VBUS_CNTL_DPDM_PD_EN            BIT(4)
  49 #define VBUS_CNTL_DPDM_FD_EN            BIT(5)
  50 #define VBUS_CNTL_FIRST_PO_STAT         BIT(6)
  51
  52 /* BC USB status register */
  53 #define USB_STAT_BUS_STAT_MASK          (BIT(3)|BIT(2)|BIT(1)|BIT(0))
  54 #define USB_STAT_BUS_STAT_SHIFT         0
  55 #define USB_STAT_BUS_STAT_ATHD          0
  56 #define USB_STAT_BUS_STAT_CONN          1
  57 #define USB_STAT_BUS_STAT_SUSP          2
  58 #define USB_STAT_BUS_STAT_CONF          3
  59 #define USB_STAT_USB_SS_MODE            BIT(4)
  60 #define USB_STAT_DEAD_BAT_DET           BIT(6)
  61 #define USB_STAT_DBP_UNCFG              BIT(7)
  62
  63 /* BC detect status register */
  64 #define DET_STAT_MASK                   (BIT(7)|BIT(6)|BIT(5))
  65 #define DET_STAT_SHIFT                  5
  66 #define DET_STAT_SDP                    1
  67 #define DET_STAT_CDP                    2
  68 #define DET_STAT_DCP                    3
  69
  70 enum axp288_extcon_reg {
  71         AXP288_PS_STAT_REG              = 0x00,
  72         AXP288_PS_BOOT_REASON_REG       = 0x02,
  73         AXP288_BC_GLOBAL_REG            = 0x2c,
  74         AXP288_BC_VBUS_CNTL_REG         = 0x2d,
  75         AXP288_BC_USB_STAT_REG          = 0x2e,
  76         AXP288_BC_DET_STAT_REG          = 0x2f,
  77 };
  78
  79 enum axp288_extcon_irq {
  80         VBUS_FALLING_IRQ = 0,
  81         VBUS_RISING_IRQ,
  82         MV_CHNG_IRQ,
  83         BC_USB_CHNG_IRQ,
  84         EXTCON_IRQ_END,
  85 };
  86
  87 static const unsigned int axp288_extcon_cables[] = {
  88         EXTCON_CHG_USB_SDP,
  89         EXTCON_CHG_USB_CDP,
  90         EXTCON_CHG_USB_DCP,
  91         EXTCON_USB,
  92         EXTCON_NONE,
  93 };
  94
  95 struct axp288_extcon_info {
  96         struct device *dev;
  97         struct regmap *regmap;
  98         struct regmap_irq_chip_data *regmap_irqc;
  99         struct usb_role_switch *role_sw;
 100         struct work_struct role_work;
 101         int irq[EXTCON_IRQ_END];
 102         struct extcon_dev *edev;
 103         struct extcon_dev *id_extcon;
 104         struct notifier_block id_nb;
 105         unsigned int previous_cable;
 106         bool vbus_attach;
 107 };
 108
 109 static const struct x86_cpu_id cherry_trail_cpu_ids[] = {
 110         X86_MATCH_INTEL_FAM6_MODEL(ATOM_AIRMONT,        NULL),
 111         {}
 112 };
 113
 114 /* Power up/down reason string array */
 115 static const char * const axp288_pwr_up_down_info[] = {
 116         "Last wake caused by user pressing the power button",
 117         "Last wake caused by a charger insertion",
 118         "Last wake caused by a battery insertion",
 119         "Last wake caused by SOC initiated global reset",
 120         "Last wake caused by cold reset",
 121         "Last shutdown caused by PMIC UVLO threshold",
 122         "Last shutdown caused by SOC initiated cold off",
 123         "Last shutdown caused by user pressing the power button",
 124 };
 125
 126 /*
 127  * Decode and log the given "reset source indicator" (rsi)
 128  * register and then clear it.
 129  */
 130 static void axp288_extcon_log_rsi(struct axp288_extcon_info *info)
 131 {
 132         unsigned int val, i, clear_mask = 0;
 133         unsigned long bits;
 134         int ret;
 135
 136         ret = regmap_read(info->regmap, AXP288_PS_BOOT_REASON_REG, &val);
 137         if (ret < 0) {
 138                 dev_err(info->dev, "failed to read reset source indicator\n");
 139                 return;
 140         }
 141
 142         bits = val & GENMASK(ARRAY_SIZE(axp288_pwr_up_down_info) - 1, 0);
 143         for_each_set_bit(i, &bits, ARRAY_SIZE(axp288_pwr_up_down_info))
 144                 dev_dbg(info->dev, "%s\n", axp288_pwr_up_down_info[i]);
 145         clear_mask = bits;
 146
 147         /* Clear the register value for next reboot (write 1 to clear bit) */
 148         regmap_write(info->regmap, AXP288_PS_BOOT_REASON_REG, clear_mask);
 149 }
 150
 151 /*
 152  * The below code to control the USB role-switch on devices with an AXP288
 153  * may seem out of place, but there are 2 reasons why this is the best place
 154  * to control the USB role-switch on such devices:
 155  * 1) On many devices the USB role is controlled by AML code, but the AML code
 156  *    only switches between the host and none roles, because of Windows not
 157  *    really using device mode. To make device mode work we need to toggle
 158  *    between the none/device roles based on Vbus presence, and this driver
 159  *    gets interrupts on Vbus insertion / removal.
 160  * 2) In order for our BC1.2 charger detection to work properly the role
 161  *    mux must be properly set to device mode before we do the detection.
 162  */
 163
 164 /* Returns the id-pin value, note pulled low / false == host-mode */
 165 static bool axp288_get_id_pin(struct axp288_extcon_info *info)
 166 {
 167         enum usb_role role;
 168
 169         if (info->id_extcon)
 170                 return extcon_get_state(info->id_extcon, EXTCON_USB_HOST) <= 0;
 171
 172         /* We cannot access the id-pin, see what mode the AML code has set */
 173         role = usb_role_switch_get_role(info->role_sw);
 174         return role != USB_ROLE_HOST;
 175 }
 176
 177 static void axp288_usb_role_work(struct work_struct *work)
 178 {
 179         struct axp288_extcon_info *info =
 180                 container_of(work, struct axp288_extcon_info, role_work);
 181         enum usb_role role;
 182         bool id_pin;
 183         int ret;
 184
 185         id_pin = axp288_get_id_pin(info);
 186         if (!id_pin)
 187                 role = USB_ROLE_HOST;
 188         else if (info->vbus_attach)
 189                 role = USB_ROLE_DEVICE;
 190         else
 191                 role = USB_ROLE_NONE;
 192
 193         ret = usb_role_switch_set_role(info->role_sw, role);
 194         if (ret)
 195                 dev_err(info->dev, "failed to set role: %d\n", ret);
 196 }
 197
 198 static bool axp288_get_vbus_attach(struct axp288_extcon_info *info)
 199 {
 200         int ret, pwr_stat;
 201
 202         ret = regmap_read(info->regmap, AXP288_PS_STAT_REG, &pwr_stat);
 203         if (ret < 0) {
 204                 dev_err(info->dev, "failed to read vbus status\n");
 205                 return false;
 206         }
 207
 208         return !!(pwr_stat & PS_STAT_VBUS_VALID);
 209 }
 210
 211 static int axp288_handle_chrg_det_event(struct axp288_extcon_info *info)
 212 {
 213         int ret, stat, cfg;
 214         u8 chrg_type;
 215         unsigned int cable = info->previous_cable;
 216         bool vbus_attach = false;
 217
 218         vbus_attach = axp288_get_vbus_attach(info);
 219         if (!vbus_attach)
 220                 goto no_vbus;
 221
 222         /* Check charger detection completion status */
 223         ret = regmap_read(info->regmap, AXP288_BC_GLOBAL_REG, &cfg);
 224         if (ret < 0)
 225                 goto dev_det_ret;
 226         if (cfg & BC_GLOBAL_DET_STAT) {
 227                 dev_dbg(info->dev, "can't complete the charger detection\n");
 228                 goto dev_det_ret;
 229         }
 230
 231         ret = regmap_read(info->regmap, AXP288_BC_DET_STAT_REG, &stat);
 232         if (ret < 0)
 233                 goto dev_det_ret;
 234
 235         chrg_type = (stat & DET_STAT_MASK) >> DET_STAT_SHIFT;
 236
 237         switch (chrg_type) {
 238         case DET_STAT_SDP:
 239                 dev_dbg(info->dev, "sdp cable is connected\n");
 240                 cable = EXTCON_CHG_USB_SDP;
 241                 break;
 242         case DET_STAT_CDP:
 243                 dev_dbg(info->dev, "cdp cable is connected\n");
 244                 cable = EXTCON_CHG_USB_CDP;
 245                 break;
 246         case DET_STAT_DCP:
 247                 dev_dbg(info->dev, "dcp cable is connected\n");
 248                 cable = EXTCON_CHG_USB_DCP;
 249                 break;
 250         default:
 251                 dev_warn(info->dev, "unknown (reserved) bc detect result\n");
 252                 cable = EXTCON_CHG_USB_SDP;
 253         }
 254
 255 no_vbus:
 256         extcon_set_state_sync(info->edev, info->previous_cable, false);
 257         if (info->previous_cable == EXTCON_CHG_USB_SDP)
 258                 extcon_set_state_sync(info->edev, EXTCON_USB, false);
 259
 260         if (vbus_attach) {
 261                 extcon_set_state_sync(info->edev, cable, vbus_attach);
 262                 if (cable == EXTCON_CHG_USB_SDP)
 263                         extcon_set_state_sync(info->edev, EXTCON_USB,
 264                                                 vbus_attach);
 265
 266                 info->previous_cable = cable;
 267         }
 268
 269         if (info->role_sw && info->vbus_attach != vbus_attach) {
 270                 info->vbus_attach = vbus_attach;
 271                 /* Setting the role can take a while */
 272                 queue_work(system_long_wq, &info->role_work);
 273         }
 274
 275         return 0;
 276
 277 dev_det_ret:
 278         if (ret < 0)
 279                 dev_err(info->dev, "failed to detect BC Mod\n");
 280
 281         return ret;
 282 }
 283
 284 static int axp288_extcon_id_evt(struct notifier_block *nb,
 285                                 unsigned long event, void *param)
 286 {
 287         struct axp288_extcon_info *info =
 288                 container_of(nb, struct axp288_extcon_info, id_nb);
 289
 290         /* We may not sleep and setting the role can take a while */
 291         queue_work(system_long_wq, &info->role_work);
 292
 293         return NOTIFY_OK;
 294 }
 295
 296 static irqreturn_t axp288_extcon_isr(int irq, void *data)
 297 {
 298         struct axp288_extcon_info *info = data;
 299         int ret;
 300
 301         ret = axp288_handle_chrg_det_event(info);
 302         if (ret < 0)
 303                 dev_err(info->dev, "failed to handle the interrupt\n");
 304
 305         return IRQ_HANDLED;
 306 }
 307
 308 static void axp288_extcon_enable(struct axp288_extcon_info *info)
 309 {
 310         regmap_update_bits(info->regmap, AXP288_BC_GLOBAL_REG,
 311                                                 BC_GLOBAL_RUN, 0);
 312         /* Enable the charger detection logic */
 313         regmap_update_bits(info->regmap, AXP288_BC_GLOBAL_REG,
 314                                         BC_GLOBAL_RUN, BC_GLOBAL_RUN);
 315 }
 316
 317 static void axp288_put_role_sw(void *data)
 318 {
 319         struct axp288_extcon_info *info = data;
 320
 321         cancel_work_sync(&info->role_work);
 322         usb_role_switch_put(info->role_sw);
 323 }
 324
 325 static int axp288_extcon_find_role_sw(struct axp288_extcon_info *info)
 326 {
 327         const struct software_node *swnode;
 328         struct fwnode_handle *fwnode;
 329
 330         if (!x86_match_cpu(cherry_trail_cpu_ids))
 331                 return 0;
 332
 333         swnode = software_node_find_by_name(NULL, "intel-xhci-usb-sw");
 334         if (!swnode)
 335                 return -EPROBE_DEFER;
 336
 337         fwnode = software_node_fwnode(swnode);
 338         info->role_sw = usb_role_switch_find_by_fwnode(fwnode);
 339         fwnode_handle_put(fwnode);
 340
 341         return info->role_sw ? 0 : -EPROBE_DEFER;
 342 }
 343
 344 static int axp288_extcon_probe(struct platform_device *pdev)
 345 {
 346         struct axp288_extcon_info *info;
 347         struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
 348         struct device *dev = &pdev->dev;
 349         struct acpi_device *adev;
 350         int ret, i, pirq;
 351
 352         info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
 353         if (!info)
 354                 return -ENOMEM;
 355
 356         info->dev = &pdev->dev;
 357         info->regmap = axp20x->regmap;
 358         info->regmap_irqc = axp20x->regmap_irqc;
 359         info->previous_cable = EXTCON_NONE;
 360         INIT_WORK(&info->role_work, axp288_usb_role_work);
 361         info->id_nb.notifier_call = axp288_extcon_id_evt;
 362
 363         platform_set_drvdata(pdev, info);
 364
 365         ret = axp288_extcon_find_role_sw(info);
 366         if (ret)
 367                 return ret;
 368
 369         if (info->role_sw) {
 370                 ret = devm_add_action_or_reset(dev, axp288_put_role_sw, info);
 371                 if (ret)
 372                         return ret;
 373
 374                 adev = acpi_dev_get_first_match_dev("INT3496", NULL, -1);
 375                 if (adev) {
 376                         info->id_extcon = extcon_get_extcon_dev(acpi_dev_name(adev));
 377                         put_device(&adev->dev);
 378                         if (!info->id_extcon)
 379                                 return -EPROBE_DEFER;
 380
 381                         dev_info(dev, "controlling USB role\n");
 382                 } else {
 383                         dev_info(dev, "controlling USB role based on Vbus presence\n");
 384                 }
 385         }
 386
 387         info->vbus_attach = axp288_get_vbus_attach(info);
 388
 389         axp288_extcon_log_rsi(info);
 390
 391         /* Initialize extcon device */
 392         info->edev = devm_extcon_dev_allocate(&pdev->dev,
 393                                               axp288_extcon_cables);
 394         if (IS_ERR(info->edev)) {
 395                 dev_err(&pdev->dev, "failed to allocate memory for extcon\n");
 396                 return PTR_ERR(info->edev);
 397         }
 398
 399         /* Register extcon device */
 400         ret = devm_extcon_dev_register(&pdev->dev, info->edev);
 401         if (ret) {
 402                 dev_err(&pdev->dev, "failed to register extcon device\n");
 403                 return ret;
 404         }
 405
 406         for (i = 0; i < EXTCON_IRQ_END; i++) {
 407                 pirq = platform_get_irq(pdev, i);
 408                 if (pirq < 0)
 409                         return pirq;
 410
 411                 info->irq[i] = regmap_irq_get_virq(info->regmap_irqc, pirq);
 412                 if (info->irq[i] < 0) {
 413                         dev_err(&pdev->dev,
 414                                 "failed to get virtual interrupt=%d\n", pirq);
 415                         ret = info->irq[i];
 416                         return ret;
 417                 }
 418
 419                 ret = devm_request_threaded_irq(&pdev->dev, info->irq[i],
 420                                 NULL, axp288_extcon_isr,
 421                                 IRQF_ONESHOT | IRQF_NO_SUSPEND,
 422                                 pdev->name, info);
 423                 if (ret) {
 424                         dev_err(&pdev->dev, "failed to request interrupt=%d\n",
 425                                                         info->irq[i]);
 426                         return ret;
 427                 }
 428         }
 429
 430         if (info->id_extcon) {
 431                 ret = devm_extcon_register_notifier_all(dev, info->id_extcon,
 432                                                         &info->id_nb);
 433                 if (ret)
 434                         return ret;
 435         }
 436
 437         /* Make sure the role-sw is set correctly before doing BC detection */
 438         if (info->role_sw) {
 439                 queue_work(system_long_wq, &info->role_work);
 440                 flush_work(&info->role_work);
 441         }
 442
 443         /* Start charger cable type detection */
 444         axp288_extcon_enable(info);
 445
 446         device_init_wakeup(dev, true);
 447         platform_set_drvdata(pdev, info);
 448
 449         return 0;
 450 }
 451
 452 static int __maybe_unused axp288_extcon_suspend(struct device *dev)
 453 {
 454         struct axp288_extcon_info *info = dev_get_drvdata(dev);
 455
 456         if (device_may_wakeup(dev))
 457                 enable_irq_wake(info->irq[VBUS_RISING_IRQ]);
 458
 459         return 0;
 460 }
 461
 462 static int __maybe_unused axp288_extcon_resume(struct device *dev)
 463 {
 464         struct axp288_extcon_info *info = dev_get_drvdata(dev);
 465
 466         /*
 467          * Wakeup when a charger is connected to do charger-type
 468          * connection and generate an extcon event which makes the
 469          * axp288 charger driver set the input current limit.
 470          */
 471         if (device_may_wakeup(dev))
 472                 disable_irq_wake(info->irq[VBUS_RISING_IRQ]);
 473
 474         return 0;
 475 }
 476
 477 static SIMPLE_DEV_PM_OPS(axp288_extcon_pm_ops, axp288_extcon_suspend,
 478                          axp288_extcon_resume);
 479
 480 static const struct platform_device_id axp288_extcon_table[] = {
 481         { .name = "axp288_extcon" },
 482         {},
 483 };
 484 MODULE_DEVICE_TABLE(platform, axp288_extcon_table);
 485
 486 static struct platform_driver axp288_extcon_driver = {
 487         .probe = axp288_extcon_probe,
 488         .id_table = axp288_extcon_table,
 489         .driver = {
 490                 .name = "axp288_extcon",
 491                 .pm = &axp288_extcon_pm_ops,
 492         },
 493 };
 494 module_platform_driver(axp288_extcon_driver);
 495
 496 MODULE_AUTHOR("Ramakrishna Pallala <ramakrishna.pallala@intel.com>");
 497 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
 498 MODULE_DESCRIPTION("X-Powers AXP288 extcon driver");
 499 MODULE_LICENSE("GPL v2");