drivers/input/misc/pm8941-pwrkey.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2010-2011, 2020-2021, The Linux Foundation. All rights reserved.
   4  * Copyright (c) 2014, Sony Mobile Communications Inc.
   5  */
   6
   7 #include <linux/delay.h>
   8 #include <linux/errno.h>
   9 #include <linux/input.h>
  10 #include <linux/interrupt.h>
  11 #include <linux/kernel.h>
  12 #include <linux/ktime.h>
  13 #include <linux/log2.h>
  14 #include <linux/module.h>
  15 #include <linux/of.h>
  16 #include <linux/of_address.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/reboot.h>
  19 #include <linux/regmap.h>
  20
  21 #define PON_REV2                        0x01
  22
  23 #define PON_SUBTYPE                     0x05
  24
  25 #define PON_SUBTYPE_PRIMARY             0x01
  26 #define PON_SUBTYPE_SECONDARY           0x02
  27 #define PON_SUBTYPE_1REG                0x03
  28 #define PON_SUBTYPE_GEN2_PRIMARY        0x04
  29 #define PON_SUBTYPE_GEN2_SECONDARY      0x05
  30 #define PON_SUBTYPE_GEN3_PBS            0x08
  31 #define PON_SUBTYPE_GEN3_HLOS           0x09
  32
  33 #define PON_RT_STS                      0x10
  34 #define  PON_KPDPWR_N_SET               BIT(0)
  35 #define  PON_RESIN_N_SET                BIT(1)
  36 #define  PON_GEN3_RESIN_N_SET           BIT(6)
  37 #define  PON_GEN3_KPDPWR_N_SET          BIT(7)
  38
  39 #define PON_PS_HOLD_RST_CTL             0x5a
  40 #define PON_PS_HOLD_RST_CTL2            0x5b
  41 #define  PON_PS_HOLD_ENABLE             BIT(7)
  42 #define  PON_PS_HOLD_TYPE_MASK          0x0f
  43 #define  PON_PS_HOLD_TYPE_WARM_RESET    1
  44 #define  PON_PS_HOLD_TYPE_SHUTDOWN      4
  45 #define  PON_PS_HOLD_TYPE_HARD_RESET    7
  46
  47 #define PON_PULL_CTL                    0x70
  48 #define  PON_KPDPWR_PULL_UP             BIT(1)
  49 #define  PON_RESIN_PULL_UP              BIT(0)
  50
  51 #define PON_DBC_CTL                     0x71
  52 #define  PON_DBC_DELAY_MASK_GEN1        0x7
  53 #define  PON_DBC_DELAY_MASK_GEN2        0xf
  54 #define  PON_DBC_SHIFT_GEN1             6
  55 #define  PON_DBC_SHIFT_GEN2             14
  56
  57 struct pm8941_data {
  58         unsigned int    pull_up_bit;
  59         unsigned int    status_bit;
  60         bool            supports_ps_hold_poff_config;
  61         bool            supports_debounce_config;
  62         bool            has_pon_pbs;
  63         const char      *name;
  64         const char      *phys;
  65 };
  66
  67 struct pm8941_pwrkey {
  68         struct device *dev;
  69         int irq;
  70         u32 baseaddr;
  71         u32 pon_pbs_baseaddr;
  72         struct regmap *regmap;
  73         struct input_dev *input;
  74
  75         unsigned int revision;
  76         unsigned int subtype;
  77         struct notifier_block reboot_notifier;
  78
  79         u32 code;
  80         u32 sw_debounce_time_us;
  81         ktime_t sw_debounce_end_time;
  82         bool last_status;
  83         const struct pm8941_data *data;
  84 };
  85
  86 static int pm8941_reboot_notify(struct notifier_block *nb,
  87                                 unsigned long code, void *unused)
  88 {
  89         struct pm8941_pwrkey *pwrkey = container_of(nb, struct pm8941_pwrkey,
  90                                                     reboot_notifier);
  91         unsigned int enable_reg;
  92         unsigned int reset_type;
  93         int error;
  94
  95         /* PMICs with revision 0 have the enable bit in same register as ctrl */
  96         if (pwrkey->revision == 0)
  97                 enable_reg = PON_PS_HOLD_RST_CTL;
  98         else
  99                 enable_reg = PON_PS_HOLD_RST_CTL2;
 100
 101         error = regmap_update_bits(pwrkey->regmap,
 102                                    pwrkey->baseaddr + enable_reg,
 103                                    PON_PS_HOLD_ENABLE,
 104                                    0);
 105         if (error)
 106                 dev_err(pwrkey->dev,
 107                         "unable to clear ps hold reset enable: %d\n",
 108                         error);
 109
 110         /*
 111          * Updates of PON_PS_HOLD_ENABLE requires 3 sleep cycles between
 112          * writes.
 113          */
 114         usleep_range(100, 1000);
 115
 116         switch (code) {
 117         case SYS_HALT:
 118         case SYS_POWER_OFF:
 119                 reset_type = PON_PS_HOLD_TYPE_SHUTDOWN;
 120                 break;
 121         case SYS_RESTART:
 122         default:
 123                 if (reboot_mode == REBOOT_WARM)
 124                         reset_type = PON_PS_HOLD_TYPE_WARM_RESET;
 125                 else
 126                         reset_type = PON_PS_HOLD_TYPE_HARD_RESET;
 127                 break;
 128         }
 129
 130         error = regmap_update_bits(pwrkey->regmap,
 131                                    pwrkey->baseaddr + PON_PS_HOLD_RST_CTL,
 132                                    PON_PS_HOLD_TYPE_MASK,
 133                                    reset_type);
 134         if (error)
 135                 dev_err(pwrkey->dev, "unable to set ps hold reset type: %d\n",
 136                         error);
 137
 138         error = regmap_update_bits(pwrkey->regmap,
 139                                    pwrkey->baseaddr + enable_reg,
 140                                    PON_PS_HOLD_ENABLE,
 141                                    PON_PS_HOLD_ENABLE);
 142         if (error)
 143                 dev_err(pwrkey->dev, "unable to re-set enable: %d\n", error);
 144
 145         return NOTIFY_DONE;
 146 }
 147
 148 static irqreturn_t pm8941_pwrkey_irq(int irq, void *_data)
 149 {
 150         struct pm8941_pwrkey *pwrkey = _data;
 151         unsigned int sts;
 152         int err;
 153
 154         if (pwrkey->sw_debounce_time_us) {
 155                 if (ktime_before(ktime_get(), pwrkey->sw_debounce_end_time)) {
 156                         dev_dbg(pwrkey->dev,
 157                                 "ignoring key event received before debounce end %llu us\n",
 158                                 pwrkey->sw_debounce_end_time);
 159                         return IRQ_HANDLED;
 160                 }
 161         }
 162
 163         err = regmap_read(pwrkey->regmap, pwrkey->baseaddr + PON_RT_STS, &sts);
 164         if (err)
 165                 return IRQ_HANDLED;
 166
 167         sts &= pwrkey->data->status_bit;
 168
 169         if (pwrkey->sw_debounce_time_us && !sts)
 170                 pwrkey->sw_debounce_end_time = ktime_add_us(ktime_get(),
 171                                                 pwrkey->sw_debounce_time_us);
 172
 173         /*
 174          * Simulate a press event in case a release event occurred without a
 175          * corresponding press event.
 176          */
 177         if (!pwrkey->last_status && !sts) {
 178                 input_report_key(pwrkey->input, pwrkey->code, 1);
 179                 input_sync(pwrkey->input);
 180         }
 181         pwrkey->last_status = sts;
 182
 183         input_report_key(pwrkey->input, pwrkey->code, sts);
 184         input_sync(pwrkey->input);
 185
 186         return IRQ_HANDLED;
 187 }
 188
 189 static int pm8941_pwrkey_sw_debounce_init(struct pm8941_pwrkey *pwrkey)
 190 {
 191         unsigned int val, addr, mask;
 192         int error;
 193
 194         if (pwrkey->data->has_pon_pbs && !pwrkey->pon_pbs_baseaddr) {
 195                 dev_err(pwrkey->dev,
 196                         "PON_PBS address missing, can't read HW debounce time\n");
 197                 return 0;
 198         }
 199
 200         if (pwrkey->pon_pbs_baseaddr)
 201                 addr = pwrkey->pon_pbs_baseaddr + PON_DBC_CTL;
 202         else
 203                 addr = pwrkey->baseaddr + PON_DBC_CTL;
 204         error = regmap_read(pwrkey->regmap, addr, &val);
 205         if (error)
 206                 return error;
 207
 208         if (pwrkey->subtype >= PON_SUBTYPE_GEN2_PRIMARY)
 209                 mask = 0xf;
 210         else
 211                 mask = 0x7;
 212
 213         pwrkey->sw_debounce_time_us =
 214                 2 * USEC_PER_SEC / (1 << (mask - (val & mask)));
 215
 216         dev_dbg(pwrkey->dev, "SW debounce time = %u us\n",
 217                 pwrkey->sw_debounce_time_us);
 218
 219         return 0;
 220 }
 221
 222 static int pm8941_pwrkey_suspend(struct device *dev)
 223 {
 224         struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);
 225
 226         if (device_may_wakeup(dev))
 227                 enable_irq_wake(pwrkey->irq);
 228
 229         return 0;
 230 }
 231
 232 static int pm8941_pwrkey_resume(struct device *dev)
 233 {
 234         struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);
 235
 236         if (device_may_wakeup(dev))
 237                 disable_irq_wake(pwrkey->irq);
 238
 239         return 0;
 240 }
 241
 242 static DEFINE_SIMPLE_DEV_PM_OPS(pm8941_pwr_key_pm_ops,
 243                                 pm8941_pwrkey_suspend, pm8941_pwrkey_resume);
 244
 245 static int pm8941_pwrkey_probe(struct platform_device *pdev)
 246 {
 247         struct pm8941_pwrkey *pwrkey;
 248         bool pull_up;
 249         struct device *parent;
 250         struct device_node *regmap_node;
 251         const __be32 *addr;
 252         u32 req_delay, mask, delay_shift;
 253         int error;
 254
 255         if (of_property_read_u32(pdev->dev.of_node, "debounce", &req_delay))
 256                 req_delay = 15625;
 257
 258         if (req_delay > 2000000 || req_delay == 0) {
 259                 dev_err(&pdev->dev, "invalid debounce time: %u\n", req_delay);
 260                 return -EINVAL;
 261         }
 262
 263         pull_up = of_property_read_bool(pdev->dev.of_node, "bias-pull-up");
 264
 265         pwrkey = devm_kzalloc(&pdev->dev, sizeof(*pwrkey), GFP_KERNEL);
 266         if (!pwrkey)
 267                 return -ENOMEM;
 268
 269         pwrkey->dev = &pdev->dev;
 270         pwrkey->data = of_device_get_match_data(&pdev->dev);
 271
 272         parent = pdev->dev.parent;
 273         regmap_node = pdev->dev.of_node;
 274         pwrkey->regmap = dev_get_regmap(parent, NULL);
 275         if (!pwrkey->regmap) {
 276                 regmap_node = parent->of_node;
 277                 /*
 278                  * We failed to get regmap for parent. Let's see if we are
 279                  * a child of pon node and read regmap and reg from its
 280                  * parent.
 281                  */
 282                 pwrkey->regmap = dev_get_regmap(parent->parent, NULL);
 283                 if (!pwrkey->regmap) {
 284                         dev_err(&pdev->dev, "failed to locate regmap\n");
 285                         return -ENODEV;
 286                 }
 287         }
 288
 289         addr = of_get_address(regmap_node, 0, NULL, NULL);
 290         if (!addr) {
 291                 dev_err(&pdev->dev, "reg property missing\n");
 292                 return -EINVAL;
 293         }
 294         pwrkey->baseaddr = be32_to_cpup(addr);
 295
 296         if (pwrkey->data->has_pon_pbs) {
 297                 /* PON_PBS base address is optional */
 298                 addr = of_get_address(regmap_node, 1, NULL, NULL);
 299                 if (addr)
 300                         pwrkey->pon_pbs_baseaddr = be32_to_cpup(addr);
 301         }
 302
 303         pwrkey->irq = platform_get_irq(pdev, 0);
 304         if (pwrkey->irq < 0)
 305                 return pwrkey->irq;
 306
 307         error = regmap_read(pwrkey->regmap, pwrkey->baseaddr + PON_REV2,
 308                             &pwrkey->revision);
 309         if (error) {
 310                 dev_err(&pdev->dev, "failed to read revision: %d\n", error);
 311                 return error;
 312         }
 313
 314         error = regmap_read(pwrkey->regmap, pwrkey->baseaddr + PON_SUBTYPE,
 315                             &pwrkey->subtype);
 316         if (error) {
 317                 dev_err(&pdev->dev, "failed to read subtype: %d\n", error);
 318                 return error;
 319         }
 320
 321         error = of_property_read_u32(pdev->dev.of_node, "linux,code",
 322                                      &pwrkey->code);
 323         if (error) {
 324                 dev_dbg(&pdev->dev,
 325                         "no linux,code assuming power (%d)\n", error);
 326                 pwrkey->code = KEY_POWER;
 327         }
 328
 329         pwrkey->input = devm_input_allocate_device(&pdev->dev);
 330         if (!pwrkey->input) {
 331                 dev_dbg(&pdev->dev, "unable to allocate input device\n");
 332                 return -ENOMEM;
 333         }
 334
 335         input_set_capability(pwrkey->input, EV_KEY, pwrkey->code);
 336
 337         pwrkey->input->name = pwrkey->data->name;
 338         pwrkey->input->phys = pwrkey->data->phys;
 339
 340         if (pwrkey->data->supports_debounce_config) {
 341                 if (pwrkey->subtype >= PON_SUBTYPE_GEN2_PRIMARY) {
 342                         mask = PON_DBC_DELAY_MASK_GEN2;
 343                         delay_shift = PON_DBC_SHIFT_GEN2;
 344                 } else {
 345                         mask = PON_DBC_DELAY_MASK_GEN1;
 346                         delay_shift = PON_DBC_SHIFT_GEN1;
 347                 }
 348
 349                 req_delay = (req_delay << delay_shift) / USEC_PER_SEC;
 350                 req_delay = ilog2(req_delay);
 351
 352                 error = regmap_update_bits(pwrkey->regmap,
 353                                            pwrkey->baseaddr + PON_DBC_CTL,
 354                                            mask,
 355                                            req_delay);
 356                 if (error) {
 357                         dev_err(&pdev->dev, "failed to set debounce: %d\n",
 358                                 error);
 359                         return error;
 360                 }
 361         }
 362
 363         error = pm8941_pwrkey_sw_debounce_init(pwrkey);
 364         if (error)
 365                 return error;
 366
 367         if (pwrkey->data->pull_up_bit) {
 368                 error = regmap_update_bits(pwrkey->regmap,
 369                                            pwrkey->baseaddr + PON_PULL_CTL,
 370                                            pwrkey->data->pull_up_bit,
 371                                            pull_up ? pwrkey->data->pull_up_bit :
 372                                                      0);
 373                 if (error) {
 374                         dev_err(&pdev->dev, "failed to set pull: %d\n", error);
 375                         return error;
 376                 }
 377         }
 378
 379         error = devm_request_threaded_irq(&pdev->dev, pwrkey->irq,
 380                                           NULL, pm8941_pwrkey_irq,
 381                                           IRQF_ONESHOT,
 382                                           pwrkey->data->name, pwrkey);
 383         if (error) {
 384                 dev_err(&pdev->dev, "failed requesting IRQ: %d\n", error);
 385                 return error;
 386         }
 387
 388         error = input_register_device(pwrkey->input);
 389         if (error) {
 390                 dev_err(&pdev->dev, "failed to register input device: %d\n",
 391                         error);
 392                 return error;
 393         }
 394
 395         if (pwrkey->data->supports_ps_hold_poff_config) {
 396                 pwrkey->reboot_notifier.notifier_call = pm8941_reboot_notify;
 397                 error = register_reboot_notifier(&pwrkey->reboot_notifier);
 398                 if (error) {
 399                         dev_err(&pdev->dev, "failed to register reboot notifier: %d\n",
 400                                 error);
 401                         return error;
 402                 }
 403         }
 404
 405         platform_set_drvdata(pdev, pwrkey);
 406         device_init_wakeup(&pdev->dev, 1);
 407
 408         return 0;
 409 }
 410
 411 static void pm8941_pwrkey_remove(struct platform_device *pdev)
 412 {
 413         struct pm8941_pwrkey *pwrkey = platform_get_drvdata(pdev);
 414
 415         if (pwrkey->data->supports_ps_hold_poff_config)
 416                 unregister_reboot_notifier(&pwrkey->reboot_notifier);
 417 }
 418
 419 static const struct pm8941_data pwrkey_data = {
 420         .pull_up_bit = PON_KPDPWR_PULL_UP,
 421         .status_bit = PON_KPDPWR_N_SET,
 422         .name = "pm8941_pwrkey",
 423         .phys = "pm8941_pwrkey/input0",
 424         .supports_ps_hold_poff_config = true,
 425         .supports_debounce_config = true,
 426         .has_pon_pbs = false,
 427 };
 428
 429 static const struct pm8941_data resin_data = {
 430         .pull_up_bit = PON_RESIN_PULL_UP,
 431         .status_bit = PON_RESIN_N_SET,
 432         .name = "pm8941_resin",
 433         .phys = "pm8941_resin/input0",
 434         .supports_ps_hold_poff_config = true,
 435         .supports_debounce_config = true,
 436         .has_pon_pbs = false,
 437 };
 438
 439 static const struct pm8941_data pon_gen3_pwrkey_data = {
 440         .status_bit = PON_GEN3_KPDPWR_N_SET,
 441         .name = "pmic_pwrkey",
 442         .phys = "pmic_pwrkey/input0",
 443         .supports_ps_hold_poff_config = false,
 444         .supports_debounce_config = false,
 445         .has_pon_pbs = true,
 446 };
 447
 448 static const struct pm8941_data pon_gen3_resin_data = {
 449         .status_bit = PON_GEN3_RESIN_N_SET,
 450         .name = "pmic_resin",
 451         .phys = "pmic_resin/input0",
 452         .supports_ps_hold_poff_config = false,
 453         .supports_debounce_config = false,
 454         .has_pon_pbs = true,
 455 };
 456
 457 static const struct of_device_id pm8941_pwr_key_id_table[] = {
 458         { .compatible = "qcom,pm8941-pwrkey", .data = &pwrkey_data },
 459         { .compatible = "qcom,pm8941-resin", .data = &resin_data },
 460         { .compatible = "qcom,pmk8350-pwrkey", .data = &pon_gen3_pwrkey_data },
 461         { .compatible = "qcom,pmk8350-resin", .data = &pon_gen3_resin_data },
 462         { }
 463 };
 464 MODULE_DEVICE_TABLE(of, pm8941_pwr_key_id_table);
 465
 466 static struct platform_driver pm8941_pwrkey_driver = {
 467         .probe = pm8941_pwrkey_probe,
 468         .remove_new = pm8941_pwrkey_remove,
 469         .driver = {
 470                 .name = "pm8941-pwrkey",
 471                 .pm = pm_sleep_ptr(&pm8941_pwr_key_pm_ops),
 472                 .of_match_table = of_match_ptr(pm8941_pwr_key_id_table),
 473         },
 474 };
 475 module_platform_driver(pm8941_pwrkey_driver);
 476
 477 MODULE_DESCRIPTION("PM8941 Power Key driver");
 478 MODULE_LICENSE("GPL v2");