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_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_AIRMONT, X86_FEATURE_ANY },
 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_probe(struct platform_device *pdev)
 326 {
 327         struct axp288_extcon_info *info;
 328         struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
 329         struct device *dev = &pdev->dev;
 330         struct acpi_device *adev;
 331         int ret, i, pirq;
 332
 333         info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
 334         if (!info)
 335                 return -ENOMEM;
 336
 337         info->dev = &pdev->dev;
 338         info->regmap = axp20x->regmap;
 339         info->regmap_irqc = axp20x->regmap_irqc;
 340         info->previous_cable = EXTCON_NONE;
 341         INIT_WORK(&info->role_work, axp288_usb_role_work);
 342         info->id_nb.notifier_call = axp288_extcon_id_evt;
 343
 344         platform_set_drvdata(pdev, info);
 345
 346         info->role_sw = usb_role_switch_get(dev);
 347         if (IS_ERR(info->role_sw))
 348                 return PTR_ERR(info->role_sw);
 349         if (info->role_sw) {
 350                 ret = devm_add_action_or_reset(dev, axp288_put_role_sw, info);
 351                 if (ret)
 352                         return ret;
 353
 354                 adev = acpi_dev_get_first_match_dev("INT3496", NULL, -1);
 355                 if (adev) {
 356                         info->id_extcon = extcon_get_extcon_dev(acpi_dev_name(adev));
 357                         put_device(&adev->dev);
 358                         if (!info->id_extcon)
 359                                 return -EPROBE_DEFER;
 360
 361                         dev_info(dev, "controlling USB role\n");
 362                 } else {
 363                         dev_info(dev, "controlling USB role based on Vbus presence\n");
 364                 }
 365         }
 366
 367         info->vbus_attach = axp288_get_vbus_attach(info);
 368
 369         axp288_extcon_log_rsi(info);
 370
 371         /* Initialize extcon device */
 372         info->edev = devm_extcon_dev_allocate(&pdev->dev,
 373                                               axp288_extcon_cables);
 374         if (IS_ERR(info->edev)) {
 375                 dev_err(&pdev->dev, "failed to allocate memory for extcon\n");
 376                 return PTR_ERR(info->edev);
 377         }
 378
 379         /* Register extcon device */
 380         ret = devm_extcon_dev_register(&pdev->dev, info->edev);
 381         if (ret) {
 382                 dev_err(&pdev->dev, "failed to register extcon device\n");
 383                 return ret;
 384         }
 385
 386         for (i = 0; i < EXTCON_IRQ_END; i++) {
 387                 pirq = platform_get_irq(pdev, i);
 388                 if (pirq < 0)
 389                         return pirq;
 390
 391                 info->irq[i] = regmap_irq_get_virq(info->regmap_irqc, pirq);
 392                 if (info->irq[i] < 0) {
 393                         dev_err(&pdev->dev,
 394                                 "failed to get virtual interrupt=%d\n", pirq);
 395                         ret = info->irq[i];
 396                         return ret;
 397                 }
 398
 399                 ret = devm_request_threaded_irq(&pdev->dev, info->irq[i],
 400                                 NULL, axp288_extcon_isr,
 401                                 IRQF_ONESHOT | IRQF_NO_SUSPEND,
 402                                 pdev->name, info);
 403                 if (ret) {
 404                         dev_err(&pdev->dev, "failed to request interrupt=%d\n",
 405                                                         info->irq[i]);
 406                         return ret;
 407                 }
 408         }
 409
 410         if (info->id_extcon) {
 411                 ret = devm_extcon_register_notifier_all(dev, info->id_extcon,
 412                                                         &info->id_nb);
 413                 if (ret)
 414                         return ret;
 415         }
 416
 417         /* Make sure the role-sw is set correctly before doing BC detection */
 418         if (info->role_sw) {
 419                 queue_work(system_long_wq, &info->role_work);
 420                 flush_work(&info->role_work);
 421         }
 422
 423         /* Start charger cable type detection */
 424         axp288_extcon_enable(info);
 425
 426         return 0;
 427 }
 428
 429 static const struct platform_device_id axp288_extcon_table[] = {
 430         { .name = "axp288_extcon" },
 431         {},
 432 };
 433 MODULE_DEVICE_TABLE(platform, axp288_extcon_table);
 434
 435 static struct platform_driver axp288_extcon_driver = {
 436         .probe = axp288_extcon_probe,
 437         .id_table = axp288_extcon_table,
 438         .driver = {
 439                 .name = "axp288_extcon",
 440         },
 441 };
 442
 443 static struct device_connection axp288_extcon_role_sw_conn = {
 444         .endpoint[0] = "axp288_extcon",
 445         .endpoint[1] = "intel_xhci_usb_sw-role-switch",
 446         .id = "usb-role-switch",
 447 };
 448
 449 static int __init axp288_extcon_init(void)
 450 {
 451         if (x86_match_cpu(cherry_trail_cpu_ids))
 452                 device_connection_add(&axp288_extcon_role_sw_conn);
 453
 454         return platform_driver_register(&axp288_extcon_driver);
 455 }
 456 module_init(axp288_extcon_init);
 457
 458 static void __exit axp288_extcon_exit(void)
 459 {
 460         if (x86_match_cpu(cherry_trail_cpu_ids))
 461                 device_connection_remove(&axp288_extcon_role_sw_conn);
 462
 463         platform_driver_unregister(&axp288_extcon_driver);
 464 }
 465 module_exit(axp288_extcon_exit);
 466
 467 MODULE_AUTHOR("Ramakrishna Pallala <ramakrishna.pallala@intel.com>");
 468 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
 469 MODULE_DESCRIPTION("X-Powers AXP288 extcon driver");
 470 MODULE_LICENSE("GPL v2");