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