2 * rtc-tps80031.c -- TI TPS80031/TPS80032 RTC driver
4 * RTC driver for TI TPS80031/TPS80032 Fully Integrated
5 * Power Management with Power Path and Battery Charger
7 * Copyright (c) 2012, NVIDIA Corporation.
9 * Author: Laxman Dewangan <ldewangan@nvidia.com>
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License as
13 * published by the Free Software Foundation version 2.
15 * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
16 * whether express or implied; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
26 #include <linux/bcd.h>
27 #include <linux/device.h>
28 #include <linux/err.h>
29 #include <linux/init.h>
30 #include <linux/kernel.h>
31 #include <linux/module.h>
32 #include <linux/mfd/tps80031.h>
33 #include <linux/platform_device.h>
35 #include <linux/rtc.h>
36 #include <linux/slab.h>
38 #define ENABLE_ALARM_INT 0x08
39 #define ALARM_INT_STATUS 0x40
42 * Setting bit to 1 in STOP_RTC will run the RTC and
43 * setting this bit to 0 will freeze RTC.
47 /* Power on reset Values of RTC registers */
48 #define TPS80031_RTC_POR_YEAR 0
49 #define TPS80031_RTC_POR_MONTH 1
50 #define TPS80031_RTC_POR_DAY 1
52 /* Numbers of registers for time and alarms */
53 #define TPS80031_RTC_TIME_NUM_REGS 7
54 #define TPS80031_RTC_ALARM_NUM_REGS 6
57 * PMU RTC have only 2 nibbles to store year information, so using an
58 * offset of 100 to set the base year as 2000 for our driver.
60 #define RTC_YEAR_OFFSET 100
63 struct rtc_device
*rtc
;
67 static int tps80031_rtc_read_time(struct device
*dev
, struct rtc_time
*tm
)
69 u8 buff
[TPS80031_RTC_TIME_NUM_REGS
];
72 ret
= tps80031_reads(dev
->parent
, TPS80031_SLAVE_ID1
,
73 TPS80031_SECONDS_REG
, TPS80031_RTC_TIME_NUM_REGS
, buff
);
75 dev_err(dev
, "reading RTC_SECONDS_REG failed, err = %d\n", ret
);
79 tm
->tm_sec
= bcd2bin(buff
[0]);
80 tm
->tm_min
= bcd2bin(buff
[1]);
81 tm
->tm_hour
= bcd2bin(buff
[2]);
82 tm
->tm_mday
= bcd2bin(buff
[3]);
83 tm
->tm_mon
= bcd2bin(buff
[4]) - 1;
84 tm
->tm_year
= bcd2bin(buff
[5]) + RTC_YEAR_OFFSET
;
85 tm
->tm_wday
= bcd2bin(buff
[6]);
89 static int tps80031_rtc_set_time(struct device
*dev
, struct rtc_time
*tm
)
94 buff
[0] = bin2bcd(tm
->tm_sec
);
95 buff
[1] = bin2bcd(tm
->tm_min
);
96 buff
[2] = bin2bcd(tm
->tm_hour
);
97 buff
[3] = bin2bcd(tm
->tm_mday
);
98 buff
[4] = bin2bcd(tm
->tm_mon
+ 1);
99 buff
[5] = bin2bcd(tm
->tm_year
% RTC_YEAR_OFFSET
);
100 buff
[6] = bin2bcd(tm
->tm_wday
);
102 /* Stop RTC while updating the RTC time registers */
103 ret
= tps80031_clr_bits(dev
->parent
, TPS80031_SLAVE_ID1
,
104 TPS80031_RTC_CTRL_REG
, STOP_RTC
);
106 dev_err(dev
->parent
, "Stop RTC failed, err = %d\n", ret
);
110 ret
= tps80031_writes(dev
->parent
, TPS80031_SLAVE_ID1
,
111 TPS80031_SECONDS_REG
,
112 TPS80031_RTC_TIME_NUM_REGS
, buff
);
114 dev_err(dev
, "writing RTC_SECONDS_REG failed, err %d\n", ret
);
118 ret
= tps80031_set_bits(dev
->parent
, TPS80031_SLAVE_ID1
,
119 TPS80031_RTC_CTRL_REG
, STOP_RTC
);
121 dev_err(dev
->parent
, "Start RTC failed, err = %d\n", ret
);
125 static int tps80031_rtc_alarm_irq_enable(struct device
*dev
,
131 ret
= tps80031_set_bits(dev
->parent
, TPS80031_SLAVE_ID1
,
132 TPS80031_RTC_INTERRUPTS_REG
, ENABLE_ALARM_INT
);
134 ret
= tps80031_clr_bits(dev
->parent
, TPS80031_SLAVE_ID1
,
135 TPS80031_RTC_INTERRUPTS_REG
, ENABLE_ALARM_INT
);
137 dev_err(dev
, "Update on RTC_INT failed, err = %d\n", ret
);
143 static int tps80031_rtc_set_alarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
145 u8 buff
[TPS80031_RTC_ALARM_NUM_REGS
];
148 buff
[0] = bin2bcd(alrm
->time
.tm_sec
);
149 buff
[1] = bin2bcd(alrm
->time
.tm_min
);
150 buff
[2] = bin2bcd(alrm
->time
.tm_hour
);
151 buff
[3] = bin2bcd(alrm
->time
.tm_mday
);
152 buff
[4] = bin2bcd(alrm
->time
.tm_mon
+ 1);
153 buff
[5] = bin2bcd(alrm
->time
.tm_year
% RTC_YEAR_OFFSET
);
154 ret
= tps80031_writes(dev
->parent
, TPS80031_SLAVE_ID1
,
155 TPS80031_ALARM_SECONDS_REG
,
156 TPS80031_RTC_ALARM_NUM_REGS
, buff
);
158 dev_err(dev
, "Writing RTC_ALARM failed, err %d\n", ret
);
161 return tps80031_rtc_alarm_irq_enable(dev
, alrm
->enabled
);
164 static int tps80031_rtc_read_alarm(struct device
*dev
, struct rtc_wkalrm
*alrm
)
169 ret
= tps80031_reads(dev
->parent
, TPS80031_SLAVE_ID1
,
170 TPS80031_ALARM_SECONDS_REG
,
171 TPS80031_RTC_ALARM_NUM_REGS
, buff
);
174 "reading RTC_ALARM failed, err = %d\n", ret
);
178 alrm
->time
.tm_sec
= bcd2bin(buff
[0]);
179 alrm
->time
.tm_min
= bcd2bin(buff
[1]);
180 alrm
->time
.tm_hour
= bcd2bin(buff
[2]);
181 alrm
->time
.tm_mday
= bcd2bin(buff
[3]);
182 alrm
->time
.tm_mon
= bcd2bin(buff
[4]) - 1;
183 alrm
->time
.tm_year
= bcd2bin(buff
[5]) + RTC_YEAR_OFFSET
;
187 static int clear_alarm_int_status(struct device
*dev
, struct tps80031_rtc
*rtc
)
193 * As per datasheet, A dummy read of this RTC_STATUS_REG register
194 * is necessary before each I2C read in order to update the status
197 ret
= tps80031_read(dev
->parent
, TPS80031_SLAVE_ID1
,
198 TPS80031_RTC_STATUS_REG
, &buf
);
200 dev_err(dev
, "reading RTC_STATUS failed. err = %d\n", ret
);
204 /* clear Alarm status bits.*/
205 ret
= tps80031_set_bits(dev
->parent
, TPS80031_SLAVE_ID1
,
206 TPS80031_RTC_STATUS_REG
, ALARM_INT_STATUS
);
208 dev_err(dev
, "clear Alarm INT failed, err = %d\n", ret
);
214 static irqreturn_t
tps80031_rtc_irq(int irq
, void *data
)
216 struct device
*dev
= data
;
217 struct tps80031_rtc
*rtc
= dev_get_drvdata(dev
);
220 ret
= clear_alarm_int_status(dev
, rtc
);
224 rtc_update_irq(rtc
->rtc
, 1, RTC_IRQF
| RTC_AF
);
228 static const struct rtc_class_ops tps80031_rtc_ops
= {
229 .read_time
= tps80031_rtc_read_time
,
230 .set_time
= tps80031_rtc_set_time
,
231 .set_alarm
= tps80031_rtc_set_alarm
,
232 .read_alarm
= tps80031_rtc_read_alarm
,
233 .alarm_irq_enable
= tps80031_rtc_alarm_irq_enable
,
236 static int tps80031_rtc_probe(struct platform_device
*pdev
)
238 struct tps80031_rtc
*rtc
;
242 rtc
= devm_kzalloc(&pdev
->dev
, sizeof(*rtc
), GFP_KERNEL
);
246 rtc
->irq
= platform_get_irq(pdev
, 0);
247 platform_set_drvdata(pdev
, rtc
);
250 ret
= tps80031_set_bits(pdev
->dev
.parent
, TPS80031_SLAVE_ID1
,
251 TPS80031_RTC_CTRL_REG
, STOP_RTC
);
253 dev_err(&pdev
->dev
, "failed to start RTC. err = %d\n", ret
);
257 /* If RTC have POR values, set time 01:01:2000 */
258 tps80031_rtc_read_time(&pdev
->dev
, &tm
);
259 if ((tm
.tm_year
== RTC_YEAR_OFFSET
+ TPS80031_RTC_POR_YEAR
) &&
260 (tm
.tm_mon
== (TPS80031_RTC_POR_MONTH
- 1)) &&
261 (tm
.tm_mday
== TPS80031_RTC_POR_DAY
)) {
265 ret
= tps80031_rtc_set_time(&pdev
->dev
, &tm
);
268 "RTC set time failed, err = %d\n", ret
);
273 /* Clear alarm intretupt status if it is there */
274 ret
= clear_alarm_int_status(&pdev
->dev
, rtc
);
276 dev_err(&pdev
->dev
, "Clear alarm int failed, err = %d\n", ret
);
280 rtc
->rtc
= devm_rtc_device_register(&pdev
->dev
, pdev
->name
,
281 &tps80031_rtc_ops
, THIS_MODULE
);
282 if (IS_ERR(rtc
->rtc
)) {
283 ret
= PTR_ERR(rtc
->rtc
);
284 dev_err(&pdev
->dev
, "RTC registration failed, err %d\n", ret
);
288 ret
= devm_request_threaded_irq(&pdev
->dev
, rtc
->irq
, NULL
,
291 dev_name(&pdev
->dev
), rtc
);
293 dev_err(&pdev
->dev
, "request IRQ:%d failed, err = %d\n",
297 device_set_wakeup_capable(&pdev
->dev
, 1);
301 #ifdef CONFIG_PM_SLEEP
302 static int tps80031_rtc_suspend(struct device
*dev
)
304 struct tps80031_rtc
*rtc
= dev_get_drvdata(dev
);
306 if (device_may_wakeup(dev
))
307 enable_irq_wake(rtc
->irq
);
311 static int tps80031_rtc_resume(struct device
*dev
)
313 struct tps80031_rtc
*rtc
= dev_get_drvdata(dev
);
315 if (device_may_wakeup(dev
))
316 disable_irq_wake(rtc
->irq
);
321 static SIMPLE_DEV_PM_OPS(tps80031_pm_ops
, tps80031_rtc_suspend
,
322 tps80031_rtc_resume
);
324 static struct platform_driver tps80031_rtc_driver
= {
326 .name
= "tps80031-rtc",
327 .pm
= &tps80031_pm_ops
,
329 .probe
= tps80031_rtc_probe
,
332 module_platform_driver(tps80031_rtc_driver
);
334 MODULE_ALIAS("platform:tps80031-rtc");
335 MODULE_DESCRIPTION("TI TPS80031/TPS80032 RTC driver");
336 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
337 MODULE_LICENSE("GPL v2");