drivers/input/misc/pm8941-pwrkey.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2010-2011, Code Aurora Forum. 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/log2.h>
  13 #include <linux/module.h>
  14 #include <linux/of.h>
  15 #include <linux/of_device.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/reboot.h>
  18 #include <linux/regmap.h>
  19
  20 #define PON_REV2                        0x01
  21
  22 #define PON_RT_STS                      0x10
  23 #define  PON_KPDPWR_N_SET               BIT(0)
  24 #define  PON_RESIN_N_SET                BIT(1)
  25
  26 #define PON_PS_HOLD_RST_CTL             0x5a
  27 #define PON_PS_HOLD_RST_CTL2            0x5b
  28 #define  PON_PS_HOLD_ENABLE             BIT(7)
  29 #define  PON_PS_HOLD_TYPE_MASK          0x0f
  30 #define  PON_PS_HOLD_TYPE_SHUTDOWN      4
  31 #define  PON_PS_HOLD_TYPE_HARD_RESET    7
  32
  33 #define PON_PULL_CTL                    0x70
  34 #define  PON_KPDPWR_PULL_UP             BIT(1)
  35 #define  PON_RESIN_PULL_UP              BIT(0)
  36
  37 #define PON_DBC_CTL                     0x71
  38 #define  PON_DBC_DELAY_MASK             0x7
  39
  40 struct pm8941_data {
  41         unsigned int pull_up_bit;
  42         unsigned int status_bit;
  43 };
  44
  45 struct pm8941_pwrkey {
  46         struct device *dev;
  47         int irq;
  48         u32 baseaddr;
  49         struct regmap *regmap;
  50         struct input_dev *input;
  51
  52         unsigned int revision;
  53         struct notifier_block reboot_notifier;
  54
  55         u32 code;
  56         const struct pm8941_data *data;
  57 };
  58
  59 static int pm8941_reboot_notify(struct notifier_block *nb,
  60                                 unsigned long code, void *unused)
  61 {
  62         struct pm8941_pwrkey *pwrkey = container_of(nb, struct pm8941_pwrkey,
  63                                                     reboot_notifier);
  64         unsigned int enable_reg;
  65         unsigned int reset_type;
  66         int error;
  67
  68         /* PMICs with revision 0 have the enable bit in same register as ctrl */
  69         if (pwrkey->revision == 0)
  70                 enable_reg = PON_PS_HOLD_RST_CTL;
  71         else
  72                 enable_reg = PON_PS_HOLD_RST_CTL2;
  73
  74         error = regmap_update_bits(pwrkey->regmap,
  75                                    pwrkey->baseaddr + enable_reg,
  76                                    PON_PS_HOLD_ENABLE,
  77                                    0);
  78         if (error)
  79                 dev_err(pwrkey->dev,
  80                         "unable to clear ps hold reset enable: %d\n",
  81                         error);
  82
  83         /*
  84          * Updates of PON_PS_HOLD_ENABLE requires 3 sleep cycles between
  85          * writes.
  86          */
  87         usleep_range(100, 1000);
  88
  89         switch (code) {
  90         case SYS_HALT:
  91         case SYS_POWER_OFF:
  92                 reset_type = PON_PS_HOLD_TYPE_SHUTDOWN;
  93                 break;
  94         case SYS_RESTART:
  95         default:
  96                 reset_type = PON_PS_HOLD_TYPE_HARD_RESET;
  97                 break;
  98         }
  99
 100         error = regmap_update_bits(pwrkey->regmap,
 101                                    pwrkey->baseaddr + PON_PS_HOLD_RST_CTL,
 102                                    PON_PS_HOLD_TYPE_MASK,
 103                                    reset_type);
 104         if (error)
 105                 dev_err(pwrkey->dev, "unable to set ps hold reset type: %d\n",
 106                         error);
 107
 108         error = regmap_update_bits(pwrkey->regmap,
 109                                    pwrkey->baseaddr + enable_reg,
 110                                    PON_PS_HOLD_ENABLE,
 111                                    PON_PS_HOLD_ENABLE);
 112         if (error)
 113                 dev_err(pwrkey->dev, "unable to re-set enable: %d\n", error);
 114
 115         return NOTIFY_DONE;
 116 }
 117
 118 static irqreturn_t pm8941_pwrkey_irq(int irq, void *_data)
 119 {
 120         struct pm8941_pwrkey *pwrkey = _data;
 121         unsigned int sts;
 122         int error;
 123
 124         error = regmap_read(pwrkey->regmap,
 125                             pwrkey->baseaddr + PON_RT_STS, &sts);
 126         if (error)
 127                 return IRQ_HANDLED;
 128
 129         input_report_key(pwrkey->input, pwrkey->code,
 130                          sts & pwrkey->data->status_bit);
 131         input_sync(pwrkey->input);
 132
 133         return IRQ_HANDLED;
 134 }
 135
 136 static int __maybe_unused pm8941_pwrkey_suspend(struct device *dev)
 137 {
 138         struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);
 139
 140         if (device_may_wakeup(dev))
 141                 enable_irq_wake(pwrkey->irq);
 142
 143         return 0;
 144 }
 145
 146 static int __maybe_unused pm8941_pwrkey_resume(struct device *dev)
 147 {
 148         struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);
 149
 150         if (device_may_wakeup(dev))
 151                 disable_irq_wake(pwrkey->irq);
 152
 153         return 0;
 154 }
 155
 156 static SIMPLE_DEV_PM_OPS(pm8941_pwr_key_pm_ops,
 157                          pm8941_pwrkey_suspend, pm8941_pwrkey_resume);
 158
 159 static int pm8941_pwrkey_probe(struct platform_device *pdev)
 160 {
 161         struct pm8941_pwrkey *pwrkey;
 162         bool pull_up;
 163         struct device *parent;
 164         u32 req_delay;
 165         int error;
 166
 167         if (of_property_read_u32(pdev->dev.of_node, "debounce", &req_delay))
 168                 req_delay = 15625;
 169
 170         if (req_delay > 2000000 || req_delay == 0) {
 171                 dev_err(&pdev->dev, "invalid debounce time: %u\n", req_delay);
 172                 return -EINVAL;
 173         }
 174
 175         pull_up = of_property_read_bool(pdev->dev.of_node, "bias-pull-up");
 176
 177         pwrkey = devm_kzalloc(&pdev->dev, sizeof(*pwrkey), GFP_KERNEL);
 178         if (!pwrkey)
 179                 return -ENOMEM;
 180
 181         pwrkey->dev = &pdev->dev;
 182         pwrkey->data = of_device_get_match_data(&pdev->dev);
 183
 184         parent = pdev->dev.parent;
 185         pwrkey->regmap = dev_get_regmap(parent, NULL);
 186         if (!pwrkey->regmap) {
 187                 /*
 188                  * We failed to get regmap for parent. Let's see if we are
 189                  * a child of pon node and read regmap and reg from its
 190                  * parent.
 191                  */
 192                 pwrkey->regmap = dev_get_regmap(parent->parent, NULL);
 193                 if (!pwrkey->regmap) {
 194                         dev_err(&pdev->dev, "failed to locate regmap\n");
 195                         return -ENODEV;
 196                 }
 197
 198                 error = of_property_read_u32(parent->of_node,
 199                                              "reg", &pwrkey->baseaddr);
 200         } else {
 201                 error = of_property_read_u32(pdev->dev.of_node, "reg",
 202                                              &pwrkey->baseaddr);
 203         }
 204         if (error)
 205                 return error;
 206
 207         pwrkey->irq = platform_get_irq(pdev, 0);
 208         if (pwrkey->irq < 0)
 209                 return pwrkey->irq;
 210
 211         error = regmap_read(pwrkey->regmap, pwrkey->baseaddr + PON_REV2,
 212                             &pwrkey->revision);
 213         if (error) {
 214                 dev_err(&pdev->dev, "failed to set debounce: %d\n", error);
 215                 return error;
 216         }
 217
 218         error = of_property_read_u32(pdev->dev.of_node, "linux,code",
 219                                      &pwrkey->code);
 220         if (error) {
 221                 dev_dbg(&pdev->dev,
 222                         "no linux,code assuming power (%d)\n", error);
 223                 pwrkey->code = KEY_POWER;
 224         }
 225
 226         pwrkey->input = devm_input_allocate_device(&pdev->dev);
 227         if (!pwrkey->input) {
 228                 dev_dbg(&pdev->dev, "unable to allocate input device\n");
 229                 return -ENOMEM;
 230         }
 231
 232         input_set_capability(pwrkey->input, EV_KEY, pwrkey->code);
 233
 234         pwrkey->input->name = "pm8941_pwrkey";
 235         pwrkey->input->phys = "pm8941_pwrkey/input0";
 236
 237         req_delay = (req_delay << 6) / USEC_PER_SEC;
 238         req_delay = ilog2(req_delay);
 239
 240         error = regmap_update_bits(pwrkey->regmap,
 241                                    pwrkey->baseaddr + PON_DBC_CTL,
 242                                    PON_DBC_DELAY_MASK,
 243                                    req_delay);
 244         if (error) {
 245                 dev_err(&pdev->dev, "failed to set debounce: %d\n", error);
 246                 return error;
 247         }
 248
 249         error = regmap_update_bits(pwrkey->regmap,
 250                                    pwrkey->baseaddr + PON_PULL_CTL,
 251                                    pwrkey->data->pull_up_bit,
 252                                    pull_up ? pwrkey->data->pull_up_bit : 0);
 253         if (error) {
 254                 dev_err(&pdev->dev, "failed to set pull: %d\n", error);
 255                 return error;
 256         }
 257
 258         error = devm_request_threaded_irq(&pdev->dev, pwrkey->irq,
 259                                           NULL, pm8941_pwrkey_irq,
 260                                           IRQF_ONESHOT,
 261                                           "pm8941_pwrkey", pwrkey);
 262         if (error) {
 263                 dev_err(&pdev->dev, "failed requesting IRQ: %d\n", error);
 264                 return error;
 265         }
 266
 267         error = input_register_device(pwrkey->input);
 268         if (error) {
 269                 dev_err(&pdev->dev, "failed to register input device: %d\n",
 270                         error);
 271                 return error;
 272         }
 273
 274         pwrkey->reboot_notifier.notifier_call = pm8941_reboot_notify,
 275         error = register_reboot_notifier(&pwrkey->reboot_notifier);
 276         if (error) {
 277                 dev_err(&pdev->dev, "failed to register reboot notifier: %d\n",
 278                         error);
 279                 return error;
 280         }
 281
 282         platform_set_drvdata(pdev, pwrkey);
 283         device_init_wakeup(&pdev->dev, 1);
 284
 285         return 0;
 286 }
 287
 288 static int pm8941_pwrkey_remove(struct platform_device *pdev)
 289 {
 290         struct pm8941_pwrkey *pwrkey = platform_get_drvdata(pdev);
 291
 292         unregister_reboot_notifier(&pwrkey->reboot_notifier);
 293
 294         return 0;
 295 }
 296
 297 static const struct pm8941_data pwrkey_data = {
 298         .pull_up_bit = PON_KPDPWR_PULL_UP,
 299         .status_bit = PON_KPDPWR_N_SET,
 300 };
 301
 302 static const struct pm8941_data resin_data = {
 303         .pull_up_bit = PON_RESIN_PULL_UP,
 304         .status_bit = PON_RESIN_N_SET,
 305 };
 306
 307 static const struct of_device_id pm8941_pwr_key_id_table[] = {
 308         { .compatible = "qcom,pm8941-pwrkey", .data = &pwrkey_data },
 309         { .compatible = "qcom,pm8941-resin", .data = &resin_data },
 310         { }
 311 };
 312 MODULE_DEVICE_TABLE(of, pm8941_pwr_key_id_table);
 313
 314 static struct platform_driver pm8941_pwrkey_driver = {
 315         .probe = pm8941_pwrkey_probe,
 316         .remove = pm8941_pwrkey_remove,
 317         .driver = {
 318                 .name = "pm8941-pwrkey",
 319                 .pm = &pm8941_pwr_key_pm_ops,
 320                 .of_match_table = of_match_ptr(pm8941_pwr_key_id_table),
 321         },
 322 };
 323 module_platform_driver(pm8941_pwrkey_driver);
 324
 325 MODULE_DESCRIPTION("PM8941 Power Key driver");
 326 MODULE_LICENSE("GPL v2");