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
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