2 * rtc-twl4030.c -- TWL4030 Real Time Clock interface
4 * Copyright (C) 2007 MontaVista Software, Inc
5 * Author: Alexandre Rusev <source@mvista.com>
7 * Based on original TI driver twl4030-rtc.c
8 * Copyright (C) 2006 Texas Instruments, Inc.
11 * Copyright (C) 2003 MontaVista Software, Inc.
12 * Author: George G. Davis <gdavis@mvista.com> or <source@mvista.com>
13 * Copyright (C) 2006 David Brownell
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License
17 * as published by the Free Software Foundation; either version
18 * 2 of the License, or (at your option) any later version.
21 #include <linux/kernel.h>
22 #include <linux/init.h>
23 #include <linux/module.h>
24 #include <linux/types.h>
25 #include <linux/rtc.h>
26 #include <linux/bcd.h>
27 #include <linux/platform_device.h>
28 #include <linux/interrupt.h>
30 #include <linux/i2c/twl4030.h>
31 #include <linux/i2c/twl4030-rtc.h>
34 #define ALL_TIME_REGS 6
37 * Supports 1 byte read from TWL4030 RTC register.
39 static int twl4030_rtc_read_u8(u8 *data, u8 reg)
43 ret = twl4030_i2c_read_u8(TWL4030_MODULE_RTC, data, reg);
45 pr_err("twl4030_rtc: Could not read TWL4030"
46 "register %X - error %d\n", reg, ret);
51 * Supports 1 byte write to TWL4030 RTC registers.
53 static int twl4030_rtc_write_u8(u8 data, u8 reg)
57 ret = twl4030_i2c_write_u8(TWL4030_MODULE_RTC, data, reg);
59 pr_err("twl4030_rtc: Could not write TWL4030"
60 "register %X - error %d\n", reg, ret);
65 * Cache the value for timer/alarm interrupts register; this is
66 * only changed by callers holding rtc ops lock (or resume).
68 static unsigned char rtc_irq_bits;
71 * Enable timer and/or alarm interrupts.
73 static int set_rtc_irq_bit(unsigned char bit)
78 val = rtc_irq_bits | bit;
79 ret = twl4030_rtc_write_u8(val, REG_RTC_INTERRUPTS_REG);
87 * Disable timer and/or alarm interrupts.
89 static int mask_rtc_irq_bit(unsigned char bit)
94 val = rtc_irq_bits & ~bit;
95 ret = twl4030_rtc_write_u8(val, REG_RTC_INTERRUPTS_REG);
102 static inline int twl4030_rtc_alarm_irq_set_state(int enabled)
107 ret = set_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_ALARM_M);
109 ret = mask_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_ALARM_M);
114 static inline int twl4030_rtc_irq_set_state(int enabled)
119 ret = set_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_TIMER_M);
121 ret = mask_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_TIMER_M);
127 * Gets current TWL4030 RTC time and date parameters.
129 * The RTC's time/alarm representation is not what gmtime(3) requires
132 * - Months are 1..12 vs Linux 0-11
133 * - Years are 0..99 vs Linux 1900..N (we assume 21st century)
135 static int twl4030_rtc_read_time(struct device *dev, struct rtc_time *tm)
137 unsigned char rtc_data[ALL_TIME_REGS + 1];
141 ret = twl4030_rtc_read_u8(&save_control, REG_RTC_CTRL_REG);
145 save_control |= BIT_RTC_CTRL_REG_GET_TIME_M;
147 ret = twl4030_rtc_write_u8(save_control, REG_RTC_CTRL_REG);
151 ret = twl4030_i2c_read(TWL4030_MODULE_RTC, rtc_data,
152 REG_SECONDS_REG, ALL_TIME_REGS);
155 dev_err(dev, "rtc_read_time error %d\n", ret);
159 tm->tm_sec = bcd2bin(rtc_data[0]);
160 tm->tm_min = bcd2bin(rtc_data[1]);
161 tm->tm_hour = bcd2bin(rtc_data[2]);
162 tm->tm_mday = bcd2bin(rtc_data[3]);
163 tm->tm_mon = bcd2bin(rtc_data[4]) - 1;
164 tm->tm_year = bcd2bin(rtc_data[5]) + 100;
169 static int twl4030_rtc_set_time(struct device *dev, struct rtc_time *tm)
171 unsigned char save_control;
172 unsigned char rtc_data[ALL_TIME_REGS + 1];
175 rtc_data[1] = bin2bcd(tm->tm_sec);
176 rtc_data[2] = bin2bcd(tm->tm_min);
177 rtc_data[3] = bin2bcd(tm->tm_hour);
178 rtc_data[4] = bin2bcd(tm->tm_mday);
179 rtc_data[5] = bin2bcd(tm->tm_mon + 1);
180 rtc_data[6] = bin2bcd(tm->tm_year - 100);
182 /* Stop RTC while updating the TC registers */
183 ret = twl4030_rtc_read_u8(&save_control, REG_RTC_CTRL_REG);
187 save_control &= ~BIT_RTC_CTRL_REG_STOP_RTC_M;
188 twl4030_rtc_write_u8(save_control, REG_RTC_CTRL_REG);
192 /* update all the time registers in one shot */
193 ret = twl4030_i2c_write(TWL4030_MODULE_RTC, rtc_data,
194 REG_SECONDS_REG, ALL_TIME_REGS);
196 dev_err(dev, "rtc_set_time error %d\n", ret);
201 save_control |= BIT_RTC_CTRL_REG_STOP_RTC_M;
202 ret = twl4030_rtc_write_u8(save_control, REG_RTC_CTRL_REG);
209 * Gets current TWL4030 RTC alarm time.
211 static int twl4030_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
213 unsigned char rtc_data[ALL_TIME_REGS + 1];
216 ret = twl4030_i2c_read(TWL4030_MODULE_RTC, rtc_data,
217 REG_ALARM_SECONDS_REG, ALL_TIME_REGS);
219 dev_err(dev, "rtc_read_alarm error %d\n", ret);
223 /* some of these fields may be wildcard/"match all" */
224 alm->time.tm_sec = bcd2bin(rtc_data[0]);
225 alm->time.tm_min = bcd2bin(rtc_data[1]);
226 alm->time.tm_hour = bcd2bin(rtc_data[2]);
227 alm->time.tm_mday = bcd2bin(rtc_data[3]);
228 alm->time.tm_mon = bcd2bin(rtc_data[4]) - 1;
229 alm->time.tm_year = bcd2bin(rtc_data[5]) + 100;
231 /* report cached alarm enable state */
232 if (rtc_irq_bits & BIT_RTC_INTERRUPTS_REG_IT_ALARM_M)
238 static int twl4030_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
240 unsigned char alarm_data[ALL_TIME_REGS + 1];
243 ret = twl4030_rtc_alarm_irq_set_state(0);
247 alarm_data[1] = bin2bcd(alm->time.tm_sec);
248 alarm_data[2] = bin2bcd(alm->time.tm_min);
249 alarm_data[3] = bin2bcd(alm->time.tm_hour);
250 alarm_data[4] = bin2bcd(alm->time.tm_mday);
251 alarm_data[5] = bin2bcd(alm->time.tm_mon + 1);
252 alarm_data[6] = bin2bcd(alm->time.tm_year - 100);
254 /* update all the alarm registers in one shot */
255 ret = twl4030_i2c_write(TWL4030_MODULE_RTC, alarm_data,
256 REG_ALARM_SECONDS_REG, ALL_TIME_REGS);
258 dev_err(dev, "rtc_set_alarm error %d\n", ret);
263 ret = twl4030_rtc_alarm_irq_set_state(1);
268 #ifdef CONFIG_RTC_INTF_DEV
270 static int twl4030_rtc_ioctl(struct device *dev, unsigned int cmd,
275 return twl4030_rtc_alarm_irq_set_state(0);
277 return twl4030_rtc_alarm_irq_set_state(1);
279 return twl4030_rtc_irq_set_state(0);
281 return twl4030_rtc_irq_set_state(1);
289 #define omap_rtc_ioctl NULL
292 static irqreturn_t twl4030_rtc_interrupt(int irq, void *rtc)
294 unsigned long events = 0;
299 res = twl4030_rtc_read_u8(&rd_reg, REG_RTC_STATUS_REG);
303 * Figure out source of interrupt: ALARM or TIMER in RTC_STATUS_REG.
304 * only one (ALARM or RTC) interrupt source may be enabled
305 * at time, we also could check our results
306 * by reading RTS_INTERRUPTS_REGISTER[IT_TIMER,IT_ALARM]
308 if (rd_reg & BIT_RTC_STATUS_REG_ALARM_M)
309 events |= RTC_IRQF | RTC_AF;
311 events |= RTC_IRQF | RTC_UF;
313 res = twl4030_rtc_write_u8(rd_reg | BIT_RTC_STATUS_REG_ALARM_M,
318 /* Clear on Read enabled. RTC_IT bit of REG_PWR_ISR1 needs
319 * 2 reads to clear the interrupt. One read is done in
320 * do_twl4030_pwrirq(). Doing the second read, to clear
323 res = twl4030_i2c_read_u8(TWL4030_MODULE_INT, &rd_reg, REG_PWR_ISR1);
327 /* Notify RTC core on event */
328 rtc_update_irq(rtc, 1, events);
335 static struct rtc_class_ops twl4030_rtc_ops = {
336 .ioctl = twl4030_rtc_ioctl,
337 .read_time = twl4030_rtc_read_time,
338 .set_time = twl4030_rtc_set_time,
339 .read_alarm = twl4030_rtc_read_alarm,
340 .set_alarm = twl4030_rtc_set_alarm,
343 static int __devinit twl4030_rtc_probe(struct platform_device *pdev)
345 struct twl4030rtc_platform_data *pdata = pdev->dev.platform_data;
346 struct rtc_device *rtc;
348 int irq = platform_get_irq(pdev, 0);
354 if (pdata != NULL && pdata->init != NULL) {
360 rtc = rtc_device_register(pdev->name,
361 &pdev->dev, &twl4030_rtc_ops, THIS_MODULE);
364 dev_err(&pdev->dev, "can't register RTC device, err %ld\n",
370 platform_set_drvdata(pdev, rtc);
372 ret = twl4030_rtc_read_u8(&rd_reg, REG_RTC_STATUS_REG);
377 if (rd_reg & BIT_RTC_STATUS_REG_POWER_UP_M)
378 dev_warn(&pdev->dev, "Power up reset detected.\n");
380 if (rd_reg & BIT_RTC_STATUS_REG_ALARM_M)
381 dev_warn(&pdev->dev, "Pending Alarm interrupt detected.\n");
383 /* Clear RTC Power up reset and pending alarm interrupts */
384 ret = twl4030_rtc_write_u8(rd_reg, REG_RTC_STATUS_REG);
388 ret = request_irq(irq, twl4030_rtc_interrupt,
389 0, rtc->dev.bus_id, rtc);
391 dev_err(&pdev->dev, "IRQ is not free.\n");
395 /* Check RTC module status, Enable if it is off */
396 ret = twl4030_rtc_read_u8(&rd_reg, REG_RTC_CTRL_REG);
400 if (!(rd_reg & BIT_RTC_CTRL_REG_STOP_RTC_M)) {
401 dev_info(&pdev->dev, "Enabling TWL4030-RTC.\n");
402 rd_reg = BIT_RTC_CTRL_REG_STOP_RTC_M;
403 ret = twl4030_rtc_write_u8(rd_reg, REG_RTC_CTRL_REG);
408 ret = twl4030_i2c_read_u8(TWL4030_MODULE_INT, &rd_reg, REG_PWR_IMR1);
412 rd_reg &= PWR_RTC_IT_UNMASK;
413 /* MASK PWR - we will need this */
414 ret = twl4030_i2c_write_u8(TWL4030_MODULE_INT, rd_reg, REG_PWR_IMR1);
418 ret = twl4030_i2c_read_u8(TWL4030_MODULE_INT, &rd_reg, REG_PWR_EDR1);
422 /* Rising edge detection enabled, needed for RTC alarm */
424 ret = twl4030_i2c_write_u8(TWL4030_MODULE_INT, rd_reg, REG_PWR_EDR1);
428 /* init cached IRQ enable bits */
429 ret = twl4030_rtc_read_u8(&rtc_irq_bits, REG_RTC_INTERRUPTS_REG);
439 rtc_device_unregister(rtc);
441 if (pdata != NULL && pdata->exit != NULL)
448 * Disable all TWL4030 RTC module interrupts.
449 * Sets status flag to free.
451 static int __devexit twl4030_rtc_remove(struct platform_device *pdev)
453 /* leave rtc running, but disable irqs */
454 struct twl4030rtc_platform_data *pdata = pdev->dev.platform_data;
455 struct rtc_device *rtc = platform_get_drvdata(pdev);
456 int irq = platform_get_irq(pdev, 0);
458 mask_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_ALARM_M);
459 mask_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_TIMER_M);
463 if (pdata != NULL && pdata->exit != NULL)
466 rtc_device_unregister(rtc);
467 platform_set_drvdata(pdev, NULL);
471 static void twl4030_rtc_shutdown(struct platform_device *pdev)
473 mask_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_TIMER_M |
474 BIT_RTC_INTERRUPTS_REG_IT_ALARM_M);
479 static unsigned char irqstat;
481 static int twl4030_rtc_suspend(struct platform_device *pdev, pm_message_t state)
483 irqstat = rtc_irq_bits;
485 /* REVISIT alarm may need to wake us from sleep */
486 mask_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_TIMER_M |
487 BIT_RTC_INTERRUPTS_REG_IT_ALARM_M);
491 static int twl4030_rtc_resume(struct platform_device *pdev)
493 set_rtc_irq_bit(irqstat);
498 #define twl4030_rtc_suspend NULL
499 #define twl4030_rtc_resume NULL
502 MODULE_ALIAS("platform:twl4030_rtc");
504 static struct platform_driver twl4030rtc_driver = {
505 .probe = twl4030_rtc_probe,
506 .remove = __devexit_p(twl4030_rtc_remove),
507 .shutdown = twl4030_rtc_shutdown,
508 .suspend = twl4030_rtc_suspend,
509 .resume = twl4030_rtc_resume,
511 .owner = THIS_MODULE,
512 .name = "twl4030_rtc",
516 static int __init twl4030_rtc_init(void)
518 return platform_driver_register(&twl4030rtc_driver);
520 module_init(twl4030_rtc_init);
522 static void __exit twl4030_rtc_exit(void)
524 platform_driver_unregister(&twl4030rtc_driver);
526 module_exit(twl4030_rtc_exit);
528 MODULE_AUTHOR("Texas Instruments, MontaVista Software");
529 MODULE_LICENSE("GPL");