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Release 4.14 drivers/rtc/rtc-ab8500.c

Directory: drivers/rtc
/*
 * Copyright (C) ST-Ericsson SA 2010
 *
 * License terms: GNU General Public License (GPL) version 2
 * Author: Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>
 *
 * RTC clock driver for the RTC part of the AB8500 Power management chip.
 * Based on RTC clock driver for the AB3100 Analog Baseband Chip by
 * Linus Walleij <linus.walleij@stericsson.com>
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
#include <linux/mfd/abx500.h>
#include <linux/mfd/abx500/ab8500.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/pm_wakeirq.h>


#define AB8500_RTC_SOFF_STAT_REG	0x00

#define AB8500_RTC_CC_CONF_REG		0x01

#define AB8500_RTC_READ_REQ_REG		0x02

#define AB8500_RTC_WATCH_TSECMID_REG	0x03

#define AB8500_RTC_WATCH_TSECHI_REG	0x04

#define AB8500_RTC_WATCH_TMIN_LOW_REG	0x05

#define AB8500_RTC_WATCH_TMIN_MID_REG	0x06

#define AB8500_RTC_WATCH_TMIN_HI_REG	0x07

#define AB8500_RTC_ALRM_MIN_LOW_REG	0x08

#define AB8500_RTC_ALRM_MIN_MID_REG	0x09

#define AB8500_RTC_ALRM_MIN_HI_REG	0x0A

#define AB8500_RTC_STAT_REG		0x0B

#define AB8500_RTC_BKUP_CHG_REG		0x0C

#define AB8500_RTC_FORCE_BKUP_REG	0x0D

#define AB8500_RTC_CALIB_REG		0x0E

#define AB8500_RTC_SWITCH_STAT_REG	0x0F

#define AB8540_RTC_ALRM_SEC		0x22

#define AB8540_RTC_ALRM_MIN_LOW_REG	0x23

#define AB8540_RTC_ALRM_MIN_MID_REG	0x24

#define AB8540_RTC_ALRM_MIN_HI_REG	0x25

/* RtcReadRequest bits */

#define RTC_READ_REQUEST		0x01

#define RTC_WRITE_REQUEST		0x02

/* RtcCtrl bits */

#define RTC_ALARM_ENA			0x04

#define RTC_STATUS_DATA			0x01


#define COUNTS_PER_SEC			(0xF000 / 60)

#define AB8500_RTC_EPOCH		2000


static const u8 ab8500_rtc_time_regs[] = {
	AB8500_RTC_WATCH_TMIN_HI_REG, AB8500_RTC_WATCH_TMIN_MID_REG,
	AB8500_RTC_WATCH_TMIN_LOW_REG, AB8500_RTC_WATCH_TSECHI_REG,
	AB8500_RTC_WATCH_TSECMID_REG
};


static const u8 ab8500_rtc_alarm_regs[] = {
	AB8500_RTC_ALRM_MIN_HI_REG, AB8500_RTC_ALRM_MIN_MID_REG,
	AB8500_RTC_ALRM_MIN_LOW_REG
};


static const u8 ab8540_rtc_alarm_regs[] = {
	AB8540_RTC_ALRM_MIN_HI_REG, AB8540_RTC_ALRM_MIN_MID_REG,
	AB8540_RTC_ALRM_MIN_LOW_REG, AB8540_RTC_ALRM_SEC
};

/* Calculate the seconds from 1970 to 01-01-2000 00:00:00 */

static unsigned long get_elapsed_seconds(int year) { unsigned long secs; struct rtc_time tm = { .tm_year = year - 1900, .tm_mday = 1, }; /* * This function calculates secs from 1970 and not from * 1900, even if we supply the offset from year 1900. */ rtc_tm_to_time(&tm, &secs); return secs; }

Contributors

PersonTokensPropCommitsCommitProp
Virupax Sadashivpetimath45100.00%1100.00%
Total45100.00%1100.00%


static int ab8500_rtc_read_time(struct device *dev, struct rtc_time *tm) { unsigned long timeout = jiffies + HZ; int retval, i; unsigned long mins, secs; unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)]; u8 value; /* Request a data read */ retval = abx500_set_register_interruptible(dev, AB8500_RTC, AB8500_RTC_READ_REQ_REG, RTC_READ_REQUEST); if (retval < 0) return retval; /* Wait for some cycles after enabling the rtc read in ab8500 */ while (time_before(jiffies, timeout)) { retval = abx500_get_register_interruptible(dev, AB8500_RTC, AB8500_RTC_READ_REQ_REG, &value); if (retval < 0) return retval; if (!(value & RTC_READ_REQUEST)) break; usleep_range(1000, 5000); } /* Read the Watchtime registers */ for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) { retval = abx500_get_register_interruptible(dev, AB8500_RTC, ab8500_rtc_time_regs[i], &value); if (retval < 0) return retval; buf[i] = value; } mins = (buf[0] << 16) | (buf[1] << 8) | buf[2]; secs = (buf[3] << 8) | buf[4]; secs = secs / COUNTS_PER_SEC; secs = secs + (mins * 60); /* Add back the initially subtracted number of seconds */ secs += get_elapsed_seconds(AB8500_RTC_EPOCH); rtc_time_to_tm(secs, tm); return rtc_valid_tm(tm); }

Contributors

PersonTokensPropCommitsCommitProp
Virupax Sadashivpetimath22689.33%133.33%
Mattias Wallin239.09%133.33%
Linus Walleij41.58%133.33%
Total253100.00%3100.00%


static int ab8500_rtc_set_time(struct device *dev, struct rtc_time *tm) { int retval, i; unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)]; unsigned long no_secs, no_mins, secs = 0; if (tm->tm_year < (AB8500_RTC_EPOCH - 1900)) { dev_dbg(dev, "year should be equal to or greater than %d\n", AB8500_RTC_EPOCH); return -EINVAL; } /* Get the number of seconds since 1970 */ rtc_tm_to_time(tm, &secs); /* * Convert it to the number of seconds since 01-01-2000 00:00:00, since * we only have a small counter in the RTC. */ secs -= get_elapsed_seconds(AB8500_RTC_EPOCH); no_mins = secs / 60; no_secs = secs % 60; /* Make the seconds count as per the RTC resolution */ no_secs = no_secs * COUNTS_PER_SEC; buf[4] = no_secs & 0xFF; buf[3] = (no_secs >> 8) & 0xFF; buf[2] = no_mins & 0xFF; buf[1] = (no_mins >> 8) & 0xFF; buf[0] = (no_mins >> 16) & 0xFF; for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) { retval = abx500_set_register_interruptible(dev, AB8500_RTC, ab8500_rtc_time_regs[i], buf[i]); if (retval < 0) return retval; } /* Request a data write */ return abx500_set_register_interruptible(dev, AB8500_RTC, AB8500_RTC_READ_REQ_REG, RTC_WRITE_REQUEST); }

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PersonTokensPropCommitsCommitProp
Virupax Sadashivpetimath21296.36%150.00%
Mattias Wallin83.64%150.00%
Total220100.00%2100.00%


static int ab8500_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) { int retval, i; u8 rtc_ctrl, value; unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)]; unsigned long secs, mins; /* Check if the alarm is enabled or not */ retval = abx500_get_register_interruptible(dev, AB8500_RTC, AB8500_RTC_STAT_REG, &rtc_ctrl); if (retval < 0) return retval; if (rtc_ctrl & RTC_ALARM_ENA) alarm->enabled = 1; else alarm->enabled = 0; alarm->pending = 0; for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) { retval = abx500_get_register_interruptible(dev, AB8500_RTC, ab8500_rtc_alarm_regs[i], &value); if (retval < 0) return retval; buf[i] = value; } mins = (buf[0] << 16) | (buf[1] << 8) | (buf[2]); secs = mins * 60; /* Add back the initially subtracted number of seconds */ secs += get_elapsed_seconds(AB8500_RTC_EPOCH); rtc_time_to_tm(secs, &alarm->time); return rtc_valid_tm(&alarm->time); }

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PersonTokensPropCommitsCommitProp
Virupax Sadashivpetimath18189.60%150.00%
Mattias Wallin2110.40%150.00%
Total202100.00%2100.00%


static int ab8500_rtc_irq_enable(struct device *dev, unsigned int enabled) { return abx500_mask_and_set_register_interruptible(dev, AB8500_RTC, AB8500_RTC_STAT_REG, RTC_ALARM_ENA, enabled ? RTC_ALARM_ENA : 0); }

Contributors

PersonTokensPropCommitsCommitProp
Virupax Sadashivpetimath2987.88%150.00%
Mattias Wallin412.12%150.00%
Total33100.00%2100.00%


static int ab8500_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) { int retval, i; unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)]; unsigned long mins, secs = 0, cursec = 0; struct rtc_time curtm; if (alarm->time.tm_year < (AB8500_RTC_EPOCH - 1900)) { dev_dbg(dev, "year should be equal to or greater than %d\n", AB8500_RTC_EPOCH); return -EINVAL; } /* Get the number of seconds since 1970 */ rtc_tm_to_time(&alarm->time, &secs); /* * Check whether alarm is set less than 1min. * Since our RTC doesn't support alarm resolution less than 1min, * return -EINVAL, so UIE EMUL can take it up, incase of UIE_ON */ ab8500_rtc_read_time(dev, &curtm); /* Read current time */ rtc_tm_to_time(&curtm, &cursec); if ((secs - cursec) < 59) { dev_dbg(dev, "Alarm less than 1 minute not supported\r\n"); return -EINVAL; } /* * Convert it to the number of seconds since 01-01-2000 00:00:00, since * we only have a small counter in the RTC. */ secs -= get_elapsed_seconds(AB8500_RTC_EPOCH); mins = secs / 60; buf[2] = mins & 0xFF; buf[1] = (mins >> 8) & 0xFF; buf[0] = (mins >> 16) & 0xFF; /* Set the alarm time */ for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) { retval = abx500_set_register_interruptible(dev, AB8500_RTC, ab8500_rtc_alarm_regs[i], buf[i]); if (retval < 0) return retval; } return ab8500_rtc_irq_enable(dev, alarm->enabled); }

Contributors

PersonTokensPropCommitsCommitProp
Virupax Sadashivpetimath18277.12%133.33%
Ramesh Chandrasekaran5021.19%133.33%
Mattias Wallin41.69%133.33%
Total236100.00%3100.00%


static int ab8540_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) { int retval, i; unsigned char buf[ARRAY_SIZE(ab8540_rtc_alarm_regs)]; unsigned long mins, secs = 0; if (alarm->time.tm_year < (AB8500_RTC_EPOCH - 1900)) { dev_dbg(dev, "year should be equal to or greater than %d\n", AB8500_RTC_EPOCH); return -EINVAL; } /* Get the number of seconds since 1970 */ rtc_tm_to_time(&alarm->time, &secs); /* * Convert it to the number of seconds since 01-01-2000 00:00:00 */ secs -= get_elapsed_seconds(AB8500_RTC_EPOCH); mins = secs / 60; buf[3] = secs % 60; buf[2] = mins & 0xFF; buf[1] = (mins >> 8) & 0xFF; buf[0] = (mins >> 16) & 0xFF; /* Set the alarm time */ for (i = 0; i < ARRAY_SIZE(ab8540_rtc_alarm_regs); i++) { retval = abx500_set_register_interruptible(dev, AB8500_RTC, ab8540_rtc_alarm_regs[i], buf[i]); if (retval < 0) return retval; } return ab8500_rtc_irq_enable(dev, alarm->enabled); }

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PersonTokensPropCommitsCommitProp
Alexandre Torgue195100.00%1100.00%
Total195100.00%1100.00%


static int ab8500_rtc_set_calibration(struct device *dev, int calibration) { int retval; u8 rtccal = 0; /* * Check that the calibration value (which is in units of 0.5 * parts-per-million) is in the AB8500's range for RtcCalibration * register. -128 (0x80) is not permitted because the AB8500 uses * a sign-bit rather than two's complement, so 0x80 is just another * representation of zero. */ if ((calibration < -127) || (calibration > 127)) { dev_err(dev, "RtcCalibration value outside permitted range\n"); return -EINVAL; } /* * The AB8500 uses sign (in bit7) and magnitude (in bits0-7) * so need to convert to this sort of representation before writing * into RtcCalibration register... */ if (calibration >= 0) rtccal = 0x7F & calibration; else rtccal = ~(calibration - 1) | 0x80; retval = abx500_set_register_interruptible(dev, AB8500_RTC, AB8500_RTC_CALIB_REG, rtccal); return retval; }

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PersonTokensPropCommitsCommitProp
Mark Godfrey92100.00%1100.00%
Total92100.00%1100.00%


static int ab8500_rtc_get_calibration(struct device *dev, int *calibration) { int retval; u8 rtccal = 0; retval = abx500_get_register_interruptible(dev, AB8500_RTC, AB8500_RTC_CALIB_REG, &rtccal); if (retval >= 0) { /* * The AB8500 uses sign (in bit7) and magnitude (in bits0-7) * so need to convert value from RtcCalibration register into * a two's complement signed value... */ if (rtccal & 0x80) *calibration = 0 - (rtccal & 0x7F); else *calibration = 0x7F & rtccal; } return retval; }

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PersonTokensPropCommitsCommitProp
Mark Godfrey74100.00%1100.00%
Total74100.00%1100.00%


static ssize_t ab8500_sysfs_store_rtc_calibration(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { int retval; int calibration = 0; if (sscanf(buf, " %i ", &calibration) != 1) { dev_err(dev, "Failed to store RTC calibration attribute\n"); return -EINVAL; } retval = ab8500_rtc_set_calibration(dev, calibration); return retval ? retval : count; }

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PersonTokensPropCommitsCommitProp
Mark Godfrey75100.00%1100.00%
Total75100.00%1100.00%


static ssize_t ab8500_sysfs_show_rtc_calibration(struct device *dev, struct device_attribute *attr, char *buf) { int retval = 0; int calibration = 0; retval = ab8500_rtc_get_calibration(dev, &calibration); if (retval < 0) { dev_err(dev, "Failed to read RTC calibration attribute\n"); sprintf(buf, "0\n"); return retval; } return sprintf(buf, "%d\n", calibration); }

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PersonTokensPropCommitsCommitProp
Mark Godfrey75100.00%1100.00%
Total75100.00%1100.00%

static DEVICE_ATTR(rtc_calibration, S_IRUGO | S_IWUSR, ab8500_sysfs_show_rtc_calibration, ab8500_sysfs_store_rtc_calibration);
static int ab8500_sysfs_rtc_register(struct device *dev) { return device_create_file(dev, &dev_attr_rtc_calibration); }

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PersonTokensPropCommitsCommitProp
Mark Godfrey20100.00%1100.00%
Total20100.00%1100.00%


static void ab8500_sysfs_rtc_unregister(struct device *dev) { device_remove_file(dev, &dev_attr_rtc_calibration); }

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PersonTokensPropCommitsCommitProp
Mark Godfrey19100.00%1100.00%
Total19100.00%1100.00%


static irqreturn_t rtc_alarm_handler(int irq, void *data) { struct rtc_device *rtc = data; unsigned long events = RTC_IRQF | RTC_AF; dev_dbg(&rtc->dev, "%s\n", __func__); rtc_update_irq(rtc, 1, events); return IRQ_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
Virupax Sadashivpetimath52100.00%1100.00%
Total52100.00%1100.00%

static const struct rtc_class_ops ab8500_rtc_ops = { .read_time = ab8500_rtc_read_time, .set_time = ab8500_rtc_set_time, .read_alarm = ab8500_rtc_read_alarm, .set_alarm = ab8500_rtc_set_alarm, .alarm_irq_enable = ab8500_rtc_irq_enable, }; static const struct rtc_class_ops ab8540_rtc_ops = { .read_time = ab8500_rtc_read_time, .set_time = ab8500_rtc_set_time, .read_alarm = ab8500_rtc_read_alarm, .set_alarm = ab8540_rtc_set_alarm, .alarm_irq_enable = ab8500_rtc_irq_enable, }; static const struct platform_device_id ab85xx_rtc_ids[] = { { "ab8500-rtc", (kernel_ulong_t)&ab8500_rtc_ops, }, { "ab8540-rtc", (kernel_ulong_t)&ab8540_rtc_ops, }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(platform, ab85xx_rtc_ids);
static int ab8500_rtc_probe(struct platform_device *pdev) { const struct platform_device_id *platid = platform_get_device_id(pdev); int err; struct rtc_device *rtc; u8 rtc_ctrl; int irq; irq = platform_get_irq_byname(pdev, "ALARM"); if (irq < 0) return irq; /* For RTC supply test */ err = abx500_mask_and_set_register_interruptible(&pdev->dev, AB8500_RTC, AB8500_RTC_STAT_REG, RTC_STATUS_DATA, RTC_STATUS_DATA); if (err < 0) return err; /* Wait for reset by the PorRtc */ usleep_range(1000, 5000); err = abx500_get_register_interruptible(&pdev->dev, AB8500_RTC, AB8500_RTC_STAT_REG, &rtc_ctrl); if (err < 0) return err; /* Check if the RTC Supply fails */ if (!(rtc_ctrl & RTC_STATUS_DATA)) { dev_err(&pdev->dev, "RTC supply failure\n"); return -ENODEV; } device_init_wakeup(&pdev->dev, true); rtc = devm_rtc_device_register(&pdev->dev, "ab8500-rtc", (struct rtc_class_ops *)platid->driver_data, THIS_MODULE); if (IS_ERR(rtc)) { dev_err(&pdev->dev, "Registration failed\n"); err = PTR_ERR(rtc); return err; } err = devm_request_threaded_irq(&pdev->dev, irq, NULL, rtc_alarm_handler, IRQF_ONESHOT, "ab8500-rtc", rtc); if (err < 0) return err; dev_pm_set_wake_irq(&pdev->dev, irq); platform_set_drvdata(pdev, rtc); err = ab8500_sysfs_rtc_register(&pdev->dev); if (err) { dev_err(&pdev->dev, "sysfs RTC failed to register\n"); return err; } rtc->uie_unsupported = 1; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Virupax Sadashivpetimath18162.41%110.00%
Mark Godfrey2910.00%110.00%
Mattias Wallin217.24%110.00%
Alexandre Torgue196.55%110.00%
Sudeep Holla103.45%110.00%
Andrew Lynn103.45%110.00%
Jingoo Han93.10%110.00%
Xunlei Pang62.07%110.00%
Linus Walleij41.38%110.00%
Lee Jones10.34%110.00%
Total290100.00%10100.00%


static int ab8500_rtc_remove(struct platform_device *pdev) { dev_pm_clear_wake_irq(&pdev->dev); device_init_wakeup(&pdev->dev, false); ab8500_sysfs_rtc_unregister(&pdev->dev); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Sudeep Holla1845.00%133.33%
Virupax Sadashivpetimath1435.00%133.33%
Mark Godfrey820.00%133.33%
Total40100.00%3100.00%

static struct platform_driver ab8500_rtc_driver = { .driver = { .name = "ab8500-rtc", }, .probe = ab8500_rtc_probe, .remove = ab8500_rtc_remove, .id_table = ab85xx_rtc_ids, }; module_platform_driver(ab8500_rtc_driver); MODULE_AUTHOR("Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>"); MODULE_DESCRIPTION("AB8500 RTC Driver"); MODULE_LICENSE("GPL v2");

Overall Contributors

PersonTokensPropCommitsCommitProp
Virupax Sadashivpetimath132658.18%15.88%
Mark Godfrey40617.81%15.88%
Alexandre Torgue31113.65%15.88%
Mattias Wallin1024.48%15.88%
Ramesh Chandrasekaran502.19%15.88%
Sudeep Holla311.36%15.88%
Andrew Lynn100.44%15.88%
Jingoo Han90.39%15.88%
Linus Walleij90.39%211.76%
Javier Martinez Canillas70.31%15.88%
Xunlei Pang60.26%15.88%
Fabio Estevam50.22%15.88%
Lee Jones40.18%211.76%
Axel Lin20.09%15.88%
Krzysztof Kozlowski10.04%15.88%
Total2279100.00%17100.00%
Directory: drivers/rtc
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