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
24static struct device *sysctrl_dev;
25
26static 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
77shutdown:
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/*
89 * Use the AB WD to reset the platform. It will perform a hard
90 * reset instead of a soft reset. Write the reset reason to
91 * the AB before reset, which can be read upon restart.
92 */
93void ab8500_restart(char mode, const char *cmd)
94{
95	struct ab8500_platform_data *plat;
96	struct ab8500_sysctrl_platform_data *pdata;
97	u16 reason = 0;
98	u8 val;
99
100	if (sysctrl_dev == NULL) {
101		pr_err("%s: sysctrl not initialized\n", __func__);
102		return;
103	}
104
105	plat = dev_get_platdata(sysctrl_dev->parent);
106	pdata = plat->sysctrl;
107	if (pdata && pdata->reboot_reason_code)
108		reason = pdata->reboot_reason_code(cmd);
109	else
110		pr_warn("[%s] No reboot reason set. Default reason %d\n",
111			__func__, reason);
112
113	/*
114	 * Disable RTC alarm, just a precaution so that no alarm
115	 * is running when WD reset is executed.
116	 */
117	abx500_get_register_interruptible(sysctrl_dev, AB8500_RTC,
118		RTC_CTRL , &val);
119	abx500_set_register_interruptible(sysctrl_dev, AB8500_RTC,
120		RTC_CTRL , (val & ~RTC_ALARM_ENABLE));
121
122	/*
123	 * Android is not using the RTC alarm registers during reboot
124	 * so we borrow them for writing the reason of reset
125	 */
126
127	/* reason[8 LSB] */
128	val = reason & 0xFF;
129	abx500_set_register_interruptible(sysctrl_dev, AB8500_RTC,
130		AB8500_ALARM_MIN_LOW , val);
131
132	/* reason[8 MSB] */
133	val = (reason>>8) & 0xFF;
134	abx500_set_register_interruptible(sysctrl_dev, AB8500_RTC,
135		AB8500_ALARM_MIN_MID , val);
136
137	/* Setting WD timeout to 0 */
138	ab8500_sysctrl_write(AB8500_MAINWDOGTIMER, 0xFF, 0x0);
139
140	/* Setting the parameters to AB8500 WD*/
141	ab8500_sysctrl_write(AB8500_MAINWDOGCTRL, 0xFF, (AB8500_ENABLE_WD |
142		AB8500_WD_RESTART_ON_EXPIRE | AB8500_KICK_WD));
143}
144
145static inline bool valid_bank(u8 bank)
146{
147	return ((bank == AB8500_SYS_CTRL1_BLOCK) ||
148		(bank == AB8500_SYS_CTRL2_BLOCK));
149}
150
151int ab8500_sysctrl_read(u16 reg, u8 *value)
152{
153	u8 bank;
154
155	if (sysctrl_dev == NULL)
156		return -EINVAL;
157
158	bank = (reg >> 8);
159	if (!valid_bank(bank))
160		return -EINVAL;
161
162	return abx500_get_register_interruptible(sysctrl_dev, bank,
163		(u8)(reg & 0xFF), value);
164}
165EXPORT_SYMBOL(ab8500_sysctrl_read);
166
167int ab8500_sysctrl_write(u16 reg, u8 mask, u8 value)
168{
169	u8 bank;
170
171	if (sysctrl_dev == NULL)
172		return -EINVAL;
173
174	bank = (reg >> 8);
175	if (!valid_bank(bank))
176		return -EINVAL;
177
178	return abx500_mask_and_set_register_interruptible(sysctrl_dev, bank,
179		(u8)(reg & 0xFF), mask, value);
180}
181EXPORT_SYMBOL(ab8500_sysctrl_write);
182
183static int ab8500_sysctrl_probe(struct platform_device *pdev)
184{
185	struct ab8500 *ab8500 = dev_get_drvdata(pdev->dev.parent);
186	struct ab8500_platform_data *plat;
187	struct ab8500_sysctrl_platform_data *pdata;
188
189	plat = dev_get_platdata(pdev->dev.parent);
190
191	if (!plat)
192		return -EINVAL;
193
194	sysctrl_dev = &pdev->dev;
195
196	if (!pm_power_off)
197		pm_power_off = ab8500_power_off;
198
199	pdata = plat->sysctrl;
200	if (pdata) {
201		int last, ret, i, j;
202
203		if (is_ab8505(ab8500))
204			last = AB8500_SYSCLKREQ4RFCLKBUF;
205		else
206			last = AB8500_SYSCLKREQ8RFCLKBUF;
207
208		for (i = AB8500_SYSCLKREQ1RFCLKBUF; i <= last; i++) {
209			j = i - AB8500_SYSCLKREQ1RFCLKBUF;
210			ret = ab8500_sysctrl_write(i, 0xff,
211					pdata->initial_req_buf_config[j]);
212			dev_dbg(&pdev->dev,
213					"Setting SysClkReq%dRfClkBuf 0x%X\n",
214					j + 1,
215					pdata->initial_req_buf_config[j]);
216			if (ret < 0) {
217				dev_err(&pdev->dev,
218					"unable to set sysClkReq%dRfClkBuf: "
219					"%d\n", j + 1, ret);
220			}
221		}
222	}
223
224	return 0;
225}
226
227static int ab8500_sysctrl_remove(struct platform_device *pdev)
228{
229	sysctrl_dev = NULL;
230
231	if (pm_power_off == ab8500_power_off)
232		pm_power_off = NULL;
233
234	return 0;
235}
236
237static struct platform_driver ab8500_sysctrl_driver = {
238	.driver = {
239		.name = "ab8500-sysctrl",
240		.owner = THIS_MODULE,
241	},
242	.probe = ab8500_sysctrl_probe,
243	.remove = ab8500_sysctrl_remove,
244};
245
246static int __init ab8500_sysctrl_init(void)
247{
248	return platform_driver_register(&ab8500_sysctrl_driver);
249}
250arch_initcall(ab8500_sysctrl_init);
251
252MODULE_AUTHOR("Mattias Nilsson <mattias.i.nilsson@stericsson.com");
253MODULE_DESCRIPTION("AB8500 system control driver");
254MODULE_LICENSE("GPL v2");
255