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 device_init_wakeup(&pdev->dev, 0); 270 unregister_reboot_notifier(&pwrkey->reboot_notifier); 271 272 return 0; 273 } 274 275 static const struct of_device_id pm8941_pwr_key_id_table[] = { 276 { .compatible = "qcom,pm8941-pwrkey" }, 277 { } 278 }; 279 MODULE_DEVICE_TABLE(of, pm8941_pwr_key_id_table); 280 281 static struct platform_driver pm8941_pwrkey_driver = { 282 .probe = pm8941_pwrkey_probe, 283 .remove = pm8941_pwrkey_remove, 284 .driver = { 285 .name = "pm8941-pwrkey", 286 .pm = &pm8941_pwr_key_pm_ops, 287 .of_match_table = of_match_ptr(pm8941_pwr_key_id_table), 288 }, 289 }; 290 module_platform_driver(pm8941_pwrkey_driver); 291 292 MODULE_DESCRIPTION("PM8941 Power Key driver"); 293 MODULE_LICENSE("GPL v2"); 294