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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 <[email protected]> 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
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 = 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);