xref: /openbmc/linux/drivers/mfd/ab8500-sysctrl.c (revision 4949009e)
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 = psy->get_property(psy, POWER_SUPPLY_PROP_ONLINE, &val);
53 
54 		if (!ret && val.intval) {
55 			charger_present = true;
56 			break;
57 		}
58 	}
59 
60 	if (!charger_present)
61 		goto shutdown;
62 
63 	/* Check if battery is known */
64 	psy = power_supply_get_by_name("ab8500_btemp");
65 	if (psy) {
66 		ret = psy->get_property(psy, POWER_SUPPLY_PROP_TECHNOLOGY,
67 					&val);
68 		if (!ret && val.intval != POWER_SUPPLY_TECHNOLOGY_UNKNOWN) {
69 			printk(KERN_INFO
70 			       "Charger \"%s\" is connected with known battery."
71 			       " Rebooting.\n",
72 			       pss[i]);
73 			machine_restart("charging");
74 		}
75 	}
76 
77 shutdown:
78 	sigfillset(&all);
79 
80 	if (!sigprocmask(SIG_BLOCK, &all, &old)) {
81 		(void)ab8500_sysctrl_set(AB8500_STW4500CTRL1,
82 					 AB8500_STW4500CTRL1_SWOFF |
83 					 AB8500_STW4500CTRL1_SWRESET4500N);
84 		(void)sigprocmask(SIG_SETMASK, &old, NULL);
85 	}
86 }
87 
88 static inline bool valid_bank(u8 bank)
89 {
90 	return ((bank == AB8500_SYS_CTRL1_BLOCK) ||
91 		(bank == AB8500_SYS_CTRL2_BLOCK));
92 }
93 
94 int ab8500_sysctrl_read(u16 reg, u8 *value)
95 {
96 	u8 bank;
97 
98 	if (sysctrl_dev == NULL)
99 		return -EINVAL;
100 
101 	bank = (reg >> 8);
102 	if (!valid_bank(bank))
103 		return -EINVAL;
104 
105 	return abx500_get_register_interruptible(sysctrl_dev, bank,
106 		(u8)(reg & 0xFF), value);
107 }
108 EXPORT_SYMBOL(ab8500_sysctrl_read);
109 
110 int ab8500_sysctrl_write(u16 reg, u8 mask, u8 value)
111 {
112 	u8 bank;
113 
114 	if (sysctrl_dev == NULL)
115 		return -EINVAL;
116 
117 	bank = (reg >> 8);
118 	if (!valid_bank(bank))
119 		return -EINVAL;
120 
121 	return abx500_mask_and_set_register_interruptible(sysctrl_dev, bank,
122 		(u8)(reg & 0xFF), mask, value);
123 }
124 EXPORT_SYMBOL(ab8500_sysctrl_write);
125 
126 static int ab8500_sysctrl_probe(struct platform_device *pdev)
127 {
128 	struct ab8500 *ab8500 = dev_get_drvdata(pdev->dev.parent);
129 	struct ab8500_platform_data *plat;
130 	struct ab8500_sysctrl_platform_data *pdata;
131 
132 	plat = dev_get_platdata(pdev->dev.parent);
133 
134 	if (!plat)
135 		return -EINVAL;
136 
137 	sysctrl_dev = &pdev->dev;
138 
139 	if (!pm_power_off)
140 		pm_power_off = ab8500_power_off;
141 
142 	pdata = plat->sysctrl;
143 	if (pdata) {
144 		int last, ret, i, j;
145 
146 		if (is_ab8505(ab8500))
147 			last = AB8500_SYSCLKREQ4RFCLKBUF;
148 		else
149 			last = AB8500_SYSCLKREQ8RFCLKBUF;
150 
151 		for (i = AB8500_SYSCLKREQ1RFCLKBUF; i <= last; i++) {
152 			j = i - AB8500_SYSCLKREQ1RFCLKBUF;
153 			ret = ab8500_sysctrl_write(i, 0xff,
154 					pdata->initial_req_buf_config[j]);
155 			dev_dbg(&pdev->dev,
156 					"Setting SysClkReq%dRfClkBuf 0x%X\n",
157 					j + 1,
158 					pdata->initial_req_buf_config[j]);
159 			if (ret < 0) {
160 				dev_err(&pdev->dev,
161 					"unable to set sysClkReq%dRfClkBuf: "
162 					"%d\n", j + 1, ret);
163 			}
164 		}
165 	}
166 
167 	return 0;
168 }
169 
170 static int ab8500_sysctrl_remove(struct platform_device *pdev)
171 {
172 	sysctrl_dev = NULL;
173 
174 	if (pm_power_off == ab8500_power_off)
175 		pm_power_off = NULL;
176 
177 	return 0;
178 }
179 
180 static struct platform_driver ab8500_sysctrl_driver = {
181 	.driver = {
182 		.name = "ab8500-sysctrl",
183 	},
184 	.probe = ab8500_sysctrl_probe,
185 	.remove = ab8500_sysctrl_remove,
186 };
187 
188 static int __init ab8500_sysctrl_init(void)
189 {
190 	return platform_driver_register(&ab8500_sysctrl_driver);
191 }
192 arch_initcall(ab8500_sysctrl_init);
193 
194 MODULE_AUTHOR("Mattias Nilsson <mattias.i.nilsson@stericsson.com");
195 MODULE_DESCRIPTION("AB8500 system control driver");
196 MODULE_LICENSE("GPL v2");
197