drivers/input/misc/pm8941-pwrkey.c

   1 /*
   2  * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
   3  * Copyright (c) 2014, Sony Mobile Communications Inc.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 and
   7  * only version 2 as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <linux/delay.h>
  16 #include <linux/errno.h>
  17 #include <linux/input.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/kernel.h>
  20 #include <linux/log2.h>
  21 #include <linux/module.h>
  22 #include <linux/of.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/reboot.h>
  25 #include <linux/regmap.h>
  26
  27 #define PON_REV2                        0x01
  28
  29 #define PON_RT_STS                      0x10
  30 #define  PON_KPDPWR_N_SET               BIT(0)
  31
  32 #define PON_PS_HOLD_RST_CTL             0x5a
  33 #define PON_PS_HOLD_RST_CTL2            0x5b
  34 #define  PON_PS_HOLD_ENABLE             BIT(7)
  35 #define  PON_PS_HOLD_TYPE_MASK          0x0f
  36 #define  PON_PS_HOLD_TYPE_SHUTDOWN      4
  37 #define  PON_PS_HOLD_TYPE_HARD_RESET    7
  38
  39 #define PON_PULL_CTL                    0x70
  40 #define  PON_KPDPWR_PULL_UP             BIT(1)
  41
  42 #define PON_DBC_CTL                     0x71
  43 #define  PON_DBC_DELAY_MASK             0x7
  44
  45
  46 struct pm8941_pwrkey {
  47         struct device *dev;
  48         int irq;
  49         u32 baseaddr;
  50         struct regmap *regmap;
  51         struct input_dev *input;
  52
  53         unsigned int revision;
  54         struct notifier_block reboot_notifier;
  55 };
  56
  57 static int pm8941_reboot_notify(struct notifier_block *nb,
  58                                 unsigned long code, void *unused)
  59 {
  60         struct pm8941_pwrkey *pwrkey = container_of(nb, struct pm8941_pwrkey,
  61                                                     reboot_notifier);
  62         unsigned int enable_reg;
  63         unsigned int reset_type;
  64         int error;
  65
  66         /* PMICs with revision 0 have the enable bit in same register as ctrl */
  67         if (pwrkey->revision == 0)
  68                 enable_reg = PON_PS_HOLD_RST_CTL;
  69         else
  70                 enable_reg = PON_PS_HOLD_RST_CTL2;
  71
  72         error = regmap_update_bits(pwrkey->regmap,
  73                                    pwrkey->baseaddr + enable_reg,
  74                                    PON_PS_HOLD_ENABLE,
  75                                    0);
  76         if (error)
  77                 dev_err(pwrkey->dev,
  78                         "unable to clear ps hold reset enable: %d\n",
  79                         error);
  80
  81         /*
  82          * Updates of PON_PS_HOLD_ENABLE requires 3 sleep cycles between
  83          * writes.
  84          */
  85         usleep_range(100, 1000);
  86
  87         switch (code) {
  88         case SYS_HALT:
  89         case SYS_POWER_OFF:
  90                 reset_type = PON_PS_HOLD_TYPE_SHUTDOWN;
  91                 break;
  92         case SYS_RESTART:
  93         default:
  94                 reset_type = PON_PS_HOLD_TYPE_HARD_RESET;
  95                 break;
  96         }
  97
  98         error = regmap_update_bits(pwrkey->regmap,
  99                                    pwrkey->baseaddr + PON_PS_HOLD_RST_CTL,
 100                                    PON_PS_HOLD_TYPE_MASK,
 101                                    reset_type);
 102         if (error)
 103                 dev_err(pwrkey->dev, "unable to set ps hold reset type: %d\n",
 104                         error);
 105
 106         error = regmap_update_bits(pwrkey->regmap,
 107                                    pwrkey->baseaddr + enable_reg,
 108                                    PON_PS_HOLD_ENABLE,
 109                                    PON_PS_HOLD_ENABLE);
 110         if (error)
 111                 dev_err(pwrkey->dev, "unable to re-set enable: %d\n", error);
 112
 113         return NOTIFY_DONE;
 114 }
 115
 116 static irqreturn_t pm8941_pwrkey_irq(int irq, void *_data)
 117 {
 118         struct pm8941_pwrkey *pwrkey = _data;
 119         unsigned int sts;
 120         int error;
 121
 122         error = regmap_read(pwrkey->regmap,
 123                             pwrkey->baseaddr + PON_RT_STS, &sts);
 124         if (error)
 125                 return IRQ_HANDLED;
 126
 127         input_report_key(pwrkey->input, KEY_POWER, !!(sts & PON_KPDPWR_N_SET));
 128         input_sync(pwrkey->input);
 129
 130         return IRQ_HANDLED;
 131 }
 132
 133 static int __maybe_unused pm8941_pwrkey_suspend(struct device *dev)
 134 {
 135         struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);
 136
 137         if (device_may_wakeup(dev))
 138                 enable_irq_wake(pwrkey->irq);
 139
 140         return 0;
 141 }
 142
 143 static int __maybe_unused pm8941_pwrkey_resume(struct device *dev)
 144 {
 145         struct pm8941_pwrkey *pwrkey = dev_get_drvdata(dev);
 146
 147         if (device_may_wakeup(dev))
 148                 disable_irq_wake(pwrkey->irq);
 149
 150         return 0;
 151 }
 152
 153 static SIMPLE_DEV_PM_OPS(pm8941_pwr_key_pm_ops,
 154                          pm8941_pwrkey_suspend, pm8941_pwrkey_resume);
 155
 156 static int pm8941_pwrkey_probe(struct platform_device *pdev)
 157 {
 158         struct pm8941_pwrkey *pwrkey;
 159         bool pull_up;
 160         u32 req_delay;
 161         int error;
 162
 163         if (of_property_read_u32(pdev->dev.of_node, "debounce", &req_delay))
 164                 req_delay = 15625;
 165
 166         if (req_delay > 2000000 || req_delay == 0) {
 167                 dev_err(&pdev->dev, "invalid debounce time: %u\n", req_delay);
 168                 return -EINVAL;
 169         }
 170
 171         pull_up = of_property_read_bool(pdev->dev.of_node, "bias-pull-up");
 172
 173         pwrkey = devm_kzalloc(&pdev->dev, sizeof(*pwrkey), GFP_KERNEL);
 174         if (!pwrkey)
 175                 return -ENOMEM;
 176
 177         pwrkey->dev = &pdev->dev;
 178
 179         pwrkey->regmap = dev_get_regmap(pdev->dev.parent, NULL);
 180         if (!pwrkey->regmap) {
 181                 dev_err(&pdev->dev, "failed to locate regmap\n");
 182                 return -ENODEV;
 183         }
 184
 185         pwrkey->irq = platform_get_irq(pdev, 0);
 186         if (pwrkey->irq < 0) {
 187                 dev_err(&pdev->dev, "failed to get irq\n");
 188                 return pwrkey->irq;
 189         }
 190
 191         error = of_property_read_u32(pdev->dev.of_node, "reg",
 192                                      &pwrkey->baseaddr);
 193         if (error)
 194                 return error;
 195
 196         error = regmap_read(pwrkey->regmap, pwrkey->baseaddr + PON_REV2,
 197                             &pwrkey->revision);
 198         if (error) {
 199                 dev_err(&pdev->dev, "failed to set debounce: %d\n", error);
 200                 return error;
 201         }
 202
 203         pwrkey->input = devm_input_allocate_device(&pdev->dev);
 204         if (!pwrkey->input) {
 205                 dev_dbg(&pdev->dev, "unable to allocate input device\n");
 206                 return -ENOMEM;
 207         }
 208
 209         input_set_capability(pwrkey->input, EV_KEY, KEY_POWER);
 210
 211         pwrkey->input->name = "pm8941_pwrkey";
 212         pwrkey->input->phys = "pm8941_pwrkey/input0";
 213
 214         req_delay = (req_delay << 6) / USEC_PER_SEC;
 215         req_delay = ilog2(req_delay);
 216
 217         error = regmap_update_bits(pwrkey->regmap,
 218                                    pwrkey->baseaddr + PON_DBC_CTL,
 219                                    PON_DBC_DELAY_MASK,
 220                                    req_delay);
 221         if (error) {
 222                 dev_err(&pdev->dev, "failed to set debounce: %d\n", error);
 223                 return error;
 224         }
 225
 226         error = regmap_update_bits(pwrkey->regmap,
 227                                    pwrkey->baseaddr + PON_PULL_CTL,
 228                                    PON_KPDPWR_PULL_UP,
 229                                    pull_up ? PON_KPDPWR_PULL_UP : 0);
 230         if (error) {
 231                 dev_err(&pdev->dev, "failed to set pull: %d\n", error);
 232                 return error;
 233         }
 234
 235         error = devm_request_threaded_irq(&pdev->dev, pwrkey->irq,
 236                                           NULL, pm8941_pwrkey_irq,
 237                                           IRQF_ONESHOT,
 238                                           "pm8941_pwrkey", pwrkey);
 239         if (error) {
 240                 dev_err(&pdev->dev, "failed requesting IRQ: %d\n", error);
 241                 return error;
 242         }
 243
 244         error = input_register_device(pwrkey->input);
 245         if (error) {
 246                 dev_err(&pdev->dev, "failed to register input device: %d\n",
 247                         error);
 248                 return error;
 249         }
 250
 251         pwrkey->reboot_notifier.notifier_call = pm8941_reboot_notify,
 252         error = register_reboot_notifier(&pwrkey->reboot_notifier);
 253         if (error) {
 254                 dev_err(&pdev->dev, "failed to register reboot notifier: %d\n",
 255                         error);
 256                 return error;
 257         }
 258
 259         platform_set_drvdata(pdev, pwrkey);
 260         device_init_wakeup(&pdev->dev, 1);
 261
 262         return 0;
 263 }
 264
 265 static int pm8941_pwrkey_remove(struct platform_device *pdev)
 266 {
 267         struct pm8941_pwrkey *pwrkey = platform_get_drvdata(pdev);
 268
 269         unregister_reboot_notifier(&pwrkey->reboot_notifier);
 270
 271         return 0;
 272 }
 273
 274 static const struct of_device_id pm8941_pwr_key_id_table[] = {
 275         { .compatible = "qcom,pm8941-pwrkey" },
 276         { }
 277 };
 278 MODULE_DEVICE_TABLE(of, pm8941_pwr_key_id_table);
 279
 280 static struct platform_driver pm8941_pwrkey_driver = {
 281         .probe = pm8941_pwrkey_probe,
 282         .remove = pm8941_pwrkey_remove,
 283         .driver = {
 284                 .name = "pm8941-pwrkey",
 285                 .pm = &pm8941_pwr_key_pm_ops,
 286                 .of_match_table = of_match_ptr(pm8941_pwr_key_id_table),
 287         },
 288 };
 289 module_platform_driver(pm8941_pwrkey_driver);
 290
 291 MODULE_DESCRIPTION("PM8941 Power Key driver");
 292 MODULE_LICENSE("GPL v2");