1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * AB8500 system control driver 4 * 5 * Copyright (C) ST-Ericsson SA 2010 6 * 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 0x08 23 #define AB8500_ALARM_MIN_MID 0x09 24 #define RTC_CTRL 0x0B 25 #define RTC_ALARM_ENABLE 0x4 26 27 static struct device *sysctrl_dev; 28 29 static 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 82 shutdown: 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 93 static inline bool valid_bank(u8 bank) 94 { 95 return ((bank == AB8500_SYS_CTRL1_BLOCK) || 96 (bank == AB8500_SYS_CTRL2_BLOCK)); 97 } 98 99 int 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 } 113 EXPORT_SYMBOL(ab8500_sysctrl_read); 114 115 int 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 } 131 EXPORT_SYMBOL(ab8500_sysctrl_write); 132 133 static 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 } 142 143 static 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 } 150 151 static const struct of_device_id ab8500_sysctrl_match[] = { 152 { .compatible = "stericsson,ab8500-sysctrl", }, 153 {} 154 }; 155 156 static 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 = ab8500_sysctrl_remove, 163 }; 164 165 static int __init ab8500_sysctrl_init(void) 166 { 167 return platform_driver_register(&ab8500_sysctrl_driver); 168 } 169 arch_initcall(ab8500_sysctrl_init); 170