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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * AB8500 system control driver4 *5 * Copyright (C) ST-Ericsson SA 20106 * Author: Mattias Nilsson <mattias.i.nilsson@stericsson.com> for ST Ericsson.7 */8 9#include <linux/err.h>10#include <linux/init.h>11#include <linux/export.h>12#include <linux/platform_device.h>13#include <linux/pm.h>14#include <linux/reboot.h>15#include <linux/signal.h>16#include <linux/power_supply.h>17#include <linux/mfd/abx500.h>18#include <linux/mfd/abx500/ab8500.h>19#include <linux/mfd/abx500/ab8500-sysctrl.h>20 21/* RtcCtrl bits */22#define AB8500_ALARM_MIN_LOW 0x0823#define AB8500_ALARM_MIN_MID 0x0924#define RTC_CTRL 0x0B25#define RTC_ALARM_ENABLE 0x426 27static struct device *sysctrl_dev;28 29static void ab8500_power_off(void)30{31 sigset_t old;32 sigset_t all;33 static const char * const pss[] = {"ab8500_ac", "ab8500_usb"};34 int i;35 bool charger_present = false;36 union power_supply_propval val;37 struct power_supply *psy;38 int ret;39 40 if (sysctrl_dev == NULL) {41 pr_err("%s: sysctrl not initialized\n", __func__);42 return;43 }44 45 /*46 * If we have a charger connected and we're powering off,47 * reboot into charge-only mode.48 */49 50 for (i = 0; i < ARRAY_SIZE(pss); i++) {51 psy = power_supply_get_by_name(pss[i]);52 if (!psy)53 continue;54 55 ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_ONLINE,56 &val);57 power_supply_put(psy);58 59 if (!ret && val.intval) {60 charger_present = true;61 break;62 }63 }64 65 if (!charger_present)66 goto shutdown;67 68 /* Check if battery is known */69 psy = power_supply_get_by_name("ab8500_btemp");70 if (psy) {71 ret = power_supply_get_property(psy,72 POWER_SUPPLY_PROP_TECHNOLOGY, &val);73 if (!ret && val.intval != POWER_SUPPLY_TECHNOLOGY_UNKNOWN) {74 pr_info("Charger '%s' is connected with known battery",75 pss[i]);76 pr_info(" - Rebooting.\n");77 machine_restart("charging");78 }79 power_supply_put(psy);80 }81 82shutdown:83 sigfillset(&all);84 85 if (!sigprocmask(SIG_BLOCK, &all, &old)) {86 (void)ab8500_sysctrl_set(AB8500_STW4500CTRL1,87 AB8500_STW4500CTRL1_SWOFF |88 AB8500_STW4500CTRL1_SWRESET4500N);89 (void)sigprocmask(SIG_SETMASK, &old, NULL);90 }91}92 93static inline bool valid_bank(u8 bank)94{95 return ((bank == AB8500_SYS_CTRL1_BLOCK) ||96 (bank == AB8500_SYS_CTRL2_BLOCK));97}98 99int ab8500_sysctrl_read(u16 reg, u8 *value)100{101 u8 bank;102 103 if (sysctrl_dev == NULL)104 return -EPROBE_DEFER;105 106 bank = (reg >> 8);107 if (!valid_bank(bank))108 return -EINVAL;109 110 return abx500_get_register_interruptible(sysctrl_dev, bank,111 (u8)(reg & 0xFF), value);112}113EXPORT_SYMBOL(ab8500_sysctrl_read);114 115int ab8500_sysctrl_write(u16 reg, u8 mask, u8 value)116{117 u8 bank;118 119 if (sysctrl_dev == NULL)120 return -EPROBE_DEFER;121 122 bank = (reg >> 8);123 if (!valid_bank(bank)) {124 pr_err("invalid bank\n");125 return -EINVAL;126 }127 128 return abx500_mask_and_set_register_interruptible(sysctrl_dev, bank,129 (u8)(reg & 0xFF), mask, value);130}131EXPORT_SYMBOL(ab8500_sysctrl_write);132 133static int ab8500_sysctrl_probe(struct platform_device *pdev)134{135 sysctrl_dev = &pdev->dev;136 137 if (!pm_power_off)138 pm_power_off = ab8500_power_off;139 140 return 0;141}142 143static void ab8500_sysctrl_remove(struct platform_device *pdev)144{145 sysctrl_dev = NULL;146 147 if (pm_power_off == ab8500_power_off)148 pm_power_off = NULL;149}150 151static const struct of_device_id ab8500_sysctrl_match[] = {152 { .compatible = "stericsson,ab8500-sysctrl", },153 {}154};155 156static struct platform_driver ab8500_sysctrl_driver = {157 .driver = {158 .name = "ab8500-sysctrl",159 .of_match_table = ab8500_sysctrl_match,160 },161 .probe = ab8500_sysctrl_probe,162 .remove_new = ab8500_sysctrl_remove,163};164 165static int __init ab8500_sysctrl_init(void)166{167 return platform_driver_register(&ab8500_sysctrl_driver);168}169arch_initcall(ab8500_sysctrl_init);170