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Venu Byravarasu90829c02012-10-04 17:14:04 -07001/*
2 * rtc-rc5t583.c -- RICOH RC5T583 Real Time Clock
3 *
4 * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
5 * Author: Venu Byravarasu <vbyravarasu@nvidia.com>
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms and conditions of the GNU General Public License,
9 * version 2, as published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 * more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>. */
18
19#include <linux/kernel.h>
20#include <linux/errno.h>
21#include <linux/init.h>
22#include <linux/module.h>
23#include <linux/types.h>
24#include <linux/rtc.h>
25#include <linux/bcd.h>
26#include <linux/platform_device.h>
27#include <linux/interrupt.h>
28#include <linux/mfd/rc5t583.h>
29
30struct rc5t583_rtc {
31 struct rtc_device *rtc;
32 /* To store the list of enabled interrupts, during system suspend */
33 u32 irqen;
34};
35
36/* Total number of RTC registers needed to set time*/
37#define NUM_TIME_REGS (RC5T583_RTC_YEAR - RC5T583_RTC_SEC + 1)
38
39/* Total number of RTC registers needed to set Y-Alarm*/
40#define NUM_YAL_REGS (RC5T583_RTC_AY_YEAR - RC5T583_RTC_AY_MIN + 1)
41
42/* Set Y-Alarm interrupt */
43#define SET_YAL BIT(5)
44
45/* Get Y-Alarm interrupt status*/
46#define GET_YAL_STATUS BIT(3)
47
48static int rc5t583_rtc_alarm_irq_enable(struct device *dev, unsigned enabled)
49{
50 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
51 u8 val;
52
53 /* Set Y-Alarm, based on 'enabled' */
54 val = enabled ? SET_YAL : 0;
55
56 return regmap_update_bits(rc5t583->regmap, RC5T583_RTC_CTL1, SET_YAL,
57 val);
58}
59
60/*
61 * Gets current rc5t583 RTC time and date parameters.
62 *
63 * The RTC's time/alarm representation is not what gmtime(3) requires
64 * Linux to use:
65 *
66 * - Months are 1..12 vs Linux 0-11
67 * - Years are 0..99 vs Linux 1900..N (we assume 21st century)
68 */
69static int rc5t583_rtc_read_time(struct device *dev, struct rtc_time *tm)
70{
71 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
72 u8 rtc_data[NUM_TIME_REGS];
73 int ret;
74
75 ret = regmap_bulk_read(rc5t583->regmap, RC5T583_RTC_SEC, rtc_data,
76 NUM_TIME_REGS);
77 if (ret < 0) {
78 dev_err(dev, "RTC read time failed with err:%d\n", ret);
79 return ret;
80 }
81
82 tm->tm_sec = bcd2bin(rtc_data[0]);
83 tm->tm_min = bcd2bin(rtc_data[1]);
84 tm->tm_hour = bcd2bin(rtc_data[2]);
85 tm->tm_wday = bcd2bin(rtc_data[3]);
86 tm->tm_mday = bcd2bin(rtc_data[4]);
87 tm->tm_mon = bcd2bin(rtc_data[5]) - 1;
88 tm->tm_year = bcd2bin(rtc_data[6]) + 100;
89
90 return ret;
91}
92
93static int rc5t583_rtc_set_time(struct device *dev, struct rtc_time *tm)
94{
95 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
96 unsigned char rtc_data[NUM_TIME_REGS];
97 int ret;
98
99 rtc_data[0] = bin2bcd(tm->tm_sec);
100 rtc_data[1] = bin2bcd(tm->tm_min);
101 rtc_data[2] = bin2bcd(tm->tm_hour);
102 rtc_data[3] = bin2bcd(tm->tm_wday);
103 rtc_data[4] = bin2bcd(tm->tm_mday);
104 rtc_data[5] = bin2bcd(tm->tm_mon + 1);
105 rtc_data[6] = bin2bcd(tm->tm_year - 100);
106
107 ret = regmap_bulk_write(rc5t583->regmap, RC5T583_RTC_SEC, rtc_data,
108 NUM_TIME_REGS);
109 if (ret < 0) {
110 dev_err(dev, "RTC set time failed with error %d\n", ret);
111 return ret;
112 }
113
114 return ret;
115}
116
117static int rc5t583_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
118{
119 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
120 unsigned char alarm_data[NUM_YAL_REGS];
121 u32 interrupt_enable;
122 int ret;
123
124 ret = regmap_bulk_read(rc5t583->regmap, RC5T583_RTC_AY_MIN, alarm_data,
125 NUM_YAL_REGS);
126 if (ret < 0) {
127 dev_err(dev, "rtc_read_alarm error %d\n", ret);
128 return ret;
129 }
130
131 alm->time.tm_min = bcd2bin(alarm_data[0]);
132 alm->time.tm_hour = bcd2bin(alarm_data[1]);
133 alm->time.tm_mday = bcd2bin(alarm_data[2]);
134 alm->time.tm_mon = bcd2bin(alarm_data[3]) - 1;
135 alm->time.tm_year = bcd2bin(alarm_data[4]) + 100;
136
137 ret = regmap_read(rc5t583->regmap, RC5T583_RTC_CTL1, &interrupt_enable);
138 if (ret < 0)
139 return ret;
140
141 /* check if YALE is set */
142 if (interrupt_enable & SET_YAL)
143 alm->enabled = 1;
144
145 return ret;
146}
147
148static int rc5t583_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
149{
150 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
151 unsigned char alarm_data[NUM_YAL_REGS];
152 int ret;
153
154 ret = rc5t583_rtc_alarm_irq_enable(dev, 0);
155 if (ret)
156 return ret;
157
158 alarm_data[0] = bin2bcd(alm->time.tm_min);
159 alarm_data[1] = bin2bcd(alm->time.tm_hour);
160 alarm_data[2] = bin2bcd(alm->time.tm_mday);
161 alarm_data[3] = bin2bcd(alm->time.tm_mon + 1);
162 alarm_data[4] = bin2bcd(alm->time.tm_year - 100);
163
164 ret = regmap_bulk_write(rc5t583->regmap, RC5T583_RTC_AY_MIN, alarm_data,
165 NUM_YAL_REGS);
166 if (ret) {
167 dev_err(dev, "rtc_set_alarm error %d\n", ret);
168 return ret;
169 }
170
171 if (alm->enabled)
172 ret = rc5t583_rtc_alarm_irq_enable(dev, 1);
173
174 return ret;
175}
176
177static irqreturn_t rc5t583_rtc_interrupt(int irq, void *rtc)
178{
179 struct device *dev = rtc;
180 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
181 struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(dev);
182 unsigned long events = 0;
183 int ret;
184 u32 rtc_reg;
185
186 ret = regmap_read(rc5t583->regmap, RC5T583_RTC_CTL2, &rtc_reg);
187 if (ret < 0)
188 return IRQ_NONE;
189
190 if (rtc_reg & GET_YAL_STATUS) {
191 events = RTC_IRQF | RTC_AF;
192 /* clear pending Y-alarm interrupt bit */
193 rtc_reg &= ~GET_YAL_STATUS;
194 }
195
196 ret = regmap_write(rc5t583->regmap, RC5T583_RTC_CTL2, rtc_reg);
197 if (ret)
198 return IRQ_NONE;
199
200 /* Notify RTC core on event */
201 rtc_update_irq(rc5t583_rtc->rtc, 1, events);
202
203 return IRQ_HANDLED;
204}
205
206static const struct rtc_class_ops rc5t583_rtc_ops = {
207 .read_time = rc5t583_rtc_read_time,
208 .set_time = rc5t583_rtc_set_time,
209 .read_alarm = rc5t583_rtc_read_alarm,
210 .set_alarm = rc5t583_rtc_set_alarm,
211 .alarm_irq_enable = rc5t583_rtc_alarm_irq_enable,
212};
213
214static int __devinit rc5t583_rtc_probe(struct platform_device *pdev)
215{
216 struct rc5t583 *rc5t583 = dev_get_drvdata(pdev->dev.parent);
217 struct rc5t583_rtc *ricoh_rtc;
218 struct rc5t583_platform_data *pmic_plat_data;
219 int ret;
220 int irq;
221
222 ricoh_rtc = devm_kzalloc(&pdev->dev, sizeof(struct rc5t583_rtc),
223 GFP_KERNEL);
224 if (!ricoh_rtc)
225 return -ENOMEM;
226
227 platform_set_drvdata(pdev, ricoh_rtc);
228
229 /* Clear pending interrupts */
230 ret = regmap_write(rc5t583->regmap, RC5T583_RTC_CTL2, 0);
231 if (ret < 0)
232 return ret;
233
234 /* clear RTC Adjust register */
235 ret = regmap_write(rc5t583->regmap, RC5T583_RTC_ADJ, 0);
236 if (ret < 0) {
237 dev_err(&pdev->dev, "unable to program rtc_adjust reg\n");
238 return -EBUSY;
239 }
240
241 pmic_plat_data = dev_get_platdata(rc5t583->dev);
242 irq = pmic_plat_data->irq_base;
243 if (irq <= 0) {
244 dev_warn(&pdev->dev, "Wake up is not possible as irq = %d\n",
245 irq);
246 return ret;
247 }
248
249 irq += RC5T583_IRQ_YALE;
250 ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
251 rc5t583_rtc_interrupt, IRQF_TRIGGER_LOW,
252 "rtc-rc5t583", &pdev->dev);
253 if (ret < 0) {
254 dev_err(&pdev->dev, "IRQ is not free.\n");
255 return ret;
256 }
257 device_init_wakeup(&pdev->dev, 1);
258
259 ricoh_rtc->rtc = rtc_device_register(pdev->name, &pdev->dev,
260 &rc5t583_rtc_ops, THIS_MODULE);
261 if (IS_ERR(ricoh_rtc->rtc)) {
262 ret = PTR_ERR(ricoh_rtc->rtc);
263 dev_err(&pdev->dev, "RTC device register: err %d\n", ret);
264 return ret;
265 }
266
267 return 0;
268}
269
270/*
271 * Disable rc5t583 RTC interrupts.
272 * Sets status flag to free.
273 */
274static int __devexit rc5t583_rtc_remove(struct platform_device *pdev)
275{
276 struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(&pdev->dev);
277
278 rc5t583_rtc_alarm_irq_enable(&rc5t583_rtc->rtc->dev, 0);
279
280 rtc_device_unregister(rc5t583_rtc->rtc);
281 return 0;
282}
283
284#ifdef CONFIG_PM_SLEEP
285
286static int rc5t583_rtc_suspend(struct device *dev)
287{
288 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
289 struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(dev);
290 int ret;
291
292 /* Store current list of enabled interrupts*/
293 ret = regmap_read(rc5t583->regmap, RC5T583_RTC_CTL1,
294 &rc5t583_rtc->irqen);
295 return ret;
296}
297
298static int rc5t583_rtc_resume(struct device *dev)
299{
300 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);
301 struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(dev);
302
303 /* Restore list of enabled interrupts before suspend */
304 return regmap_write(rc5t583->regmap, RC5T583_RTC_CTL1,
305 rc5t583_rtc->irqen);
306}
307
308static const struct dev_pm_ops rc5t583_rtc_pm_ops = {
309 .suspend = rc5t583_rtc_suspend,
310 .resume = rc5t583_rtc_resume,
311};
312
313#define DEV_PM_OPS (&rc5t583_rtc_pm_ops)
314#else
315#define DEV_PM_OPS NULL
316#endif
317
318static struct platform_driver rc5t583_rtc_driver = {
319 .probe = rc5t583_rtc_probe,
320 .remove = __devexit_p(rc5t583_rtc_remove),
321 .driver = {
322 .owner = THIS_MODULE,
323 .name = "rtc-rc5t583",
324 .pm = DEV_PM_OPS,
325 },
326};
327
328module_platform_driver(rc5t583_rtc_driver);
329MODULE_ALIAS("platform:rtc-rc5t583");
330MODULE_AUTHOR("Venu Byravarasu <vbyravarasu@nvidia.com>");
331MODULE_LICENSE("GPL v2");