xref: /openbmc/linux/drivers/mfd/ab8500-sysctrl.c (revision d0bd7f2a)
1 /*
2  * Copyright (C) ST-Ericsson SA 2010
3  * Author: Mattias Nilsson <mattias.i.nilsson@stericsson.com> for ST Ericsson.
4  * License terms: GNU General Public License (GPL) version 2
5  */
6 
7 #include <linux/err.h>
8 #include <linux/module.h>
9 #include <linux/platform_device.h>
10 #include <linux/pm.h>
11 #include <linux/reboot.h>
12 #include <linux/signal.h>
13 #include <linux/power_supply.h>
14 #include <linux/mfd/abx500.h>
15 #include <linux/mfd/abx500/ab8500.h>
16 #include <linux/mfd/abx500/ab8500-sysctrl.h>
17 
18 /* RtcCtrl bits */
19 #define AB8500_ALARM_MIN_LOW  0x08
20 #define AB8500_ALARM_MIN_MID 0x09
21 #define RTC_CTRL 0x0B
22 #define RTC_ALARM_ENABLE 0x4
23 
24 static struct device *sysctrl_dev;
25 
26 static void ab8500_power_off(void)
27 {
28 	sigset_t old;
29 	sigset_t all;
30 	static char *pss[] = {"ab8500_ac", "pm2301", "ab8500_usb"};
31 	int i;
32 	bool charger_present = false;
33 	union power_supply_propval val;
34 	struct power_supply *psy;
35 	int ret;
36 
37 	if (sysctrl_dev == NULL) {
38 		pr_err("%s: sysctrl not initialized\n", __func__);
39 		return;
40 	}
41 
42 	/*
43 	 * If we have a charger connected and we're powering off,
44 	 * reboot into charge-only mode.
45 	 */
46 
47 	for (i = 0; i < ARRAY_SIZE(pss); i++) {
48 		psy = power_supply_get_by_name(pss[i]);
49 		if (!psy)
50 			continue;
51 
52 		ret = power_supply_get_property(psy, POWER_SUPPLY_PROP_ONLINE,
53 				&val);
54 		power_supply_put(psy);
55 
56 		if (!ret && val.intval) {
57 			charger_present = true;
58 			break;
59 		}
60 	}
61 
62 	if (!charger_present)
63 		goto shutdown;
64 
65 	/* Check if battery is known */
66 	psy = power_supply_get_by_name("ab8500_btemp");
67 	if (psy) {
68 		ret = power_supply_get_property(psy,
69 				POWER_SUPPLY_PROP_TECHNOLOGY, &val);
70 		if (!ret && val.intval != POWER_SUPPLY_TECHNOLOGY_UNKNOWN) {
71 			printk(KERN_INFO
72 			       "Charger \"%s\" is connected with known battery."
73 			       " Rebooting.\n",
74 			       pss[i]);
75 			machine_restart("charging");
76 		}
77 		power_supply_put(psy);
78 	}
79 
80 shutdown:
81 	sigfillset(&all);
82 
83 	if (!sigprocmask(SIG_BLOCK, &all, &old)) {
84 		(void)ab8500_sysctrl_set(AB8500_STW4500CTRL1,
85 					 AB8500_STW4500CTRL1_SWOFF |
86 					 AB8500_STW4500CTRL1_SWRESET4500N);
87 		(void)sigprocmask(SIG_SETMASK, &old, NULL);
88 	}
89 }
90 
91 static inline bool valid_bank(u8 bank)
92 {
93 	return ((bank == AB8500_SYS_CTRL1_BLOCK) ||
94 		(bank == AB8500_SYS_CTRL2_BLOCK));
95 }
96 
97 int ab8500_sysctrl_read(u16 reg, u8 *value)
98 {
99 	u8 bank;
100 
101 	if (sysctrl_dev == NULL)
102 		return -EINVAL;
103 
104 	bank = (reg >> 8);
105 	if (!valid_bank(bank))
106 		return -EINVAL;
107 
108 	return abx500_get_register_interruptible(sysctrl_dev, bank,
109 		(u8)(reg & 0xFF), value);
110 }
111 EXPORT_SYMBOL(ab8500_sysctrl_read);
112 
113 int ab8500_sysctrl_write(u16 reg, u8 mask, u8 value)
114 {
115 	u8 bank;
116 
117 	if (sysctrl_dev == NULL)
118 		return -EINVAL;
119 
120 	bank = (reg >> 8);
121 	if (!valid_bank(bank))
122 		return -EINVAL;
123 
124 	return abx500_mask_and_set_register_interruptible(sysctrl_dev, bank,
125 		(u8)(reg & 0xFF), mask, value);
126 }
127 EXPORT_SYMBOL(ab8500_sysctrl_write);
128 
129 static int ab8500_sysctrl_probe(struct platform_device *pdev)
130 {
131 	struct ab8500 *ab8500 = dev_get_drvdata(pdev->dev.parent);
132 	struct ab8500_platform_data *plat;
133 	struct ab8500_sysctrl_platform_data *pdata;
134 
135 	plat = dev_get_platdata(pdev->dev.parent);
136 
137 	if (!plat)
138 		return -EINVAL;
139 
140 	sysctrl_dev = &pdev->dev;
141 
142 	if (!pm_power_off)
143 		pm_power_off = ab8500_power_off;
144 
145 	pdata = plat->sysctrl;
146 	if (pdata) {
147 		int last, ret, i, j;
148 
149 		if (is_ab8505(ab8500))
150 			last = AB8500_SYSCLKREQ4RFCLKBUF;
151 		else
152 			last = AB8500_SYSCLKREQ8RFCLKBUF;
153 
154 		for (i = AB8500_SYSCLKREQ1RFCLKBUF; i <= last; i++) {
155 			j = i - AB8500_SYSCLKREQ1RFCLKBUF;
156 			ret = ab8500_sysctrl_write(i, 0xff,
157 					pdata->initial_req_buf_config[j]);
158 			dev_dbg(&pdev->dev,
159 					"Setting SysClkReq%dRfClkBuf 0x%X\n",
160 					j + 1,
161 					pdata->initial_req_buf_config[j]);
162 			if (ret < 0) {
163 				dev_err(&pdev->dev,
164 					"unable to set sysClkReq%dRfClkBuf: "
165 					"%d\n", j + 1, ret);
166 			}
167 		}
168 	}
169 
170 	return 0;
171 }
172 
173 static int ab8500_sysctrl_remove(struct platform_device *pdev)
174 {
175 	sysctrl_dev = NULL;
176 
177 	if (pm_power_off == ab8500_power_off)
178 		pm_power_off = NULL;
179 
180 	return 0;
181 }
182 
183 static struct platform_driver ab8500_sysctrl_driver = {
184 	.driver = {
185 		.name = "ab8500-sysctrl",
186 	},
187 	.probe = ab8500_sysctrl_probe,
188 	.remove = ab8500_sysctrl_remove,
189 };
190 
191 static int __init ab8500_sysctrl_init(void)
192 {
193 	return platform_driver_register(&ab8500_sysctrl_driver);
194 }
195 arch_initcall(ab8500_sysctrl_init);
196 
197 MODULE_AUTHOR("Mattias Nilsson <mattias.i.nilsson@stericsson.com");
198 MODULE_DESCRIPTION("AB8500 system control driver");
199 MODULE_LICENSE("GPL v2");
200