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Release 4.14 drivers/rtc/rtc-at91rm9200.c

Directory: drivers/rtc
/*
 *      Real Time Clock interface for Linux on Atmel AT91RM9200
 *
 *      Copyright (C) 2002 Rick Bronson
 *
 *      Converted to RTC class model by Andrew Victor
 *
 *      Ported to Linux 2.6 by Steven Scholz
 *      Based on s3c2410-rtc.c Simtec Electronics
 *
 *      Based on sa1100-rtc.c by Nils Faerber
 *      Based on rtc.c by Paul Gortmaker
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 *
 */

#include <linux/bcd.h>
#include <linux/clk.h>
#include <linux/completion.h>
#include <linux/interrupt.h>
#include <linux/ioctl.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
#include <linux/spinlock.h>
#include <linux/suspend.h>
#include <linux/time.h>
#include <linux/uaccess.h>

#include "rtc-at91rm9200.h"


#define at91_rtc_read(field) \
	readl_relaxed(at91_rtc_regs + field)

#define at91_rtc_write(field, val) \
	writel_relaxed((val), at91_rtc_regs + field)


#define AT91_RTC_EPOCH		1900UL	
/* just like arch/arm/common/rtctime.c */


struct at91_rtc_config {
	
bool use_shadow_imr;
};


static const struct at91_rtc_config *at91_rtc_config;
static DECLARE_COMPLETION(at91_rtc_updated);
static DECLARE_COMPLETION(at91_rtc_upd_rdy);

static unsigned int at91_alarm_year = AT91_RTC_EPOCH;

static void __iomem *at91_rtc_regs;

static int irq;
static DEFINE_SPINLOCK(at91_rtc_lock);

static u32 at91_rtc_shadow_imr;

static bool suspended;
static DEFINE_SPINLOCK(suspended_lock);

static unsigned long cached_events;

static u32 at91_rtc_imr;

static struct clk *sclk;


static void at91_rtc_write_ier(u32 mask) { unsigned long flags; spin_lock_irqsave(&at91_rtc_lock, flags); at91_rtc_shadow_imr |= mask; at91_rtc_write(AT91_RTC_IER, mask); spin_unlock_irqrestore(&at91_rtc_lock, flags); }

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Johan Hovold40100.00%2100.00%
Total40100.00%2100.00%


static void at91_rtc_write_idr(u32 mask) { unsigned long flags; spin_lock_irqsave(&at91_rtc_lock, flags); at91_rtc_write(AT91_RTC_IDR, mask); /* * Register read back (of any RTC-register) needed to make sure * IDR-register write has reached the peripheral before updating * shadow mask. * * Note that there is still a possibility that the mask is updated * before interrupts have actually been disabled in hardware. The only * way to be certain would be to poll the IMR-register, which is is * the very register we are trying to emulate. The register read back * is a reasonable heuristic. */ at91_rtc_read(AT91_RTC_SR); at91_rtc_shadow_imr &= ~mask; spin_unlock_irqrestore(&at91_rtc_lock, flags); }

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Johan Hovold47100.00%2100.00%
Total47100.00%2100.00%


static u32 at91_rtc_read_imr(void) { unsigned long flags; u32 mask; if (at91_rtc_config->use_shadow_imr) { spin_lock_irqsave(&at91_rtc_lock, flags); mask = at91_rtc_shadow_imr; spin_unlock_irqrestore(&at91_rtc_lock, flags); } else { mask = at91_rtc_read(AT91_RTC_IMR); } return mask; }

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Johan Hovold56100.00%2100.00%
Total56100.00%2100.00%

/* * Decode time/date into rtc_time structure */
static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg, struct rtc_time *tm) { unsigned int time, date; /* must read twice in case it changes */ do { time = at91_rtc_read(timereg); date = at91_rtc_read(calreg); } while ((time != at91_rtc_read(timereg)) || (date != at91_rtc_read(calreg))); tm->tm_sec = bcd2bin((time & AT91_RTC_SEC) >> 0); tm->tm_min = bcd2bin((time & AT91_RTC_MIN) >> 8); tm->tm_hour = bcd2bin((time & AT91_RTC_HOUR) >> 16); /* * The Calendar Alarm register does not have a field for * the year - so these will return an invalid value. When an * alarm is set, at91_alarm_year will store the current year. */ tm->tm_year = bcd2bin(date & AT91_RTC_CENT) * 100; /* century */ tm->tm_year += bcd2bin((date & AT91_RTC_YEAR) >> 8); /* year */ tm->tm_wday = bcd2bin((date & AT91_RTC_DAY) >> 21) - 1; /* day of the week [0-6], Sunday=0 */ tm->tm_mon = bcd2bin((date & AT91_RTC_MONTH) >> 16) - 1; tm->tm_mday = bcd2bin((date & AT91_RTC_DATE) >> 24); }

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Andrew Victor17793.16%125.00%
Adrian Bunk84.21%125.00%
Jean-Christophe Plagniol-Villard42.11%125.00%
Lucas De Marchi10.53%125.00%
Total190100.00%4100.00%

/* * Read current time and date in RTC */
static int at91_rtc_readtime(struct device *dev, struct rtc_time *tm) { at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, tm); tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); tm->tm_year = tm->tm_year - 1900; dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__, 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec); return 0; }

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PersonTokensPropCommitsCommitProp
Andrew Victor8895.65%133.33%
Jingoo Han33.26%133.33%
Harvey Harrison11.09%133.33%
Total92100.00%3100.00%

/* * Set current time and date in RTC */
static int at91_rtc_settime(struct device *dev, struct rtc_time *tm) { unsigned long cr; dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__, 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec); wait_for_completion(&at91_rtc_upd_rdy); /* Stop Time/Calendar from counting */ cr = at91_rtc_read(AT91_RTC_CR); at91_rtc_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM); at91_rtc_write_ier(AT91_RTC_ACKUPD); wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */ at91_rtc_write_idr(AT91_RTC_ACKUPD); at91_rtc_write(AT91_RTC_TIMR, bin2bcd(tm->tm_sec) << 0 | bin2bcd(tm->tm_min) << 8 | bin2bcd(tm->tm_hour) << 16); at91_rtc_write(AT91_RTC_CALR, bin2bcd((tm->tm_year + 1900) / 100) /* century */ | bin2bcd(tm->tm_year % 100) << 8 /* year */ | bin2bcd(tm->tm_mon + 1) << 16 /* tm_mon starts at zero */ | bin2bcd(tm->tm_wday + 1) << 21 /* day of the week [0-6], Sunday=0 */ | bin2bcd(tm->tm_mday) << 24); /* Restart Time/Calendar */ cr = at91_rtc_read(AT91_RTC_CR); at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_SECEV); at91_rtc_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL | AT91_RTC_UPDTIM)); at91_rtc_write_ier(AT91_RTC_SECEV); return 0; }

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PersonTokensPropCommitsCommitProp
Andrew Victor19283.48%114.29%
Boris Brezillon187.83%114.29%
Adrian Bunk83.48%114.29%
Jean-Christophe Plagniol-Villard62.61%114.29%
Jingoo Han31.30%114.29%
Johan Hovold20.87%114.29%
Harvey Harrison10.43%114.29%
Total230100.00%7100.00%

/* * Read alarm time and date in RTC */
static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm) { struct rtc_time *tm = &alrm->time; at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm); tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); tm->tm_year = at91_alarm_year - 1900; alrm->enabled = (at91_rtc_read_imr() & AT91_RTC_ALARM) ? 1 : 0; dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__, 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec); return 0; }

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PersonTokensPropCommitsCommitProp
Andrew Victor9683.48%120.00%
David Brownell1311.30%120.00%
Jingoo Han32.61%120.00%
Johan Hovold21.74%120.00%
Harvey Harrison10.87%120.00%
Total115100.00%5100.00%

/* * Set alarm time and date in RTC */
static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm) { struct rtc_time tm; at91_rtc_decodetime(AT91_RTC_TIMR, AT91_RTC_CALR, &tm); at91_alarm_year = tm.tm_year; tm.tm_mon = alrm->time.tm_mon; tm.tm_mday = alrm->time.tm_mday; tm.tm_hour = alrm->time.tm_hour; tm.tm_min = alrm->time.tm_min; tm.tm_sec = alrm->time.tm_sec; at91_rtc_write_idr(AT91_RTC_ALARM); at91_rtc_write(AT91_RTC_TIMALR, bin2bcd(tm.tm_sec) << 0 | bin2bcd(tm.tm_min) << 8 | bin2bcd(tm.tm_hour) << 16 | AT91_RTC_HOUREN | AT91_RTC_MINEN | AT91_RTC_SECEN); at91_rtc_write(AT91_RTC_CALALR, bin2bcd(tm.tm_mon + 1) << 16 /* tm_mon starts at zero */ | bin2bcd(tm.tm_mday) << 24 | AT91_RTC_DATEEN | AT91_RTC_MTHEN); if (alrm->enabled) { at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM); at91_rtc_write_ier(AT91_RTC_ALARM); } dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__, at91_alarm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec); return 0; }

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PersonTokensPropCommitsCommitProp
Andrew Victor15773.71%111.11%
David Brownell2210.33%222.22%
Linus Pizunski209.39%111.11%
Adrian Bunk52.35%111.11%
Jingoo Han31.41%111.11%
Jean-Christophe Plagniol-Villard31.41%111.11%
Johan Hovold20.94%111.11%
Harvey Harrison10.47%111.11%
Total213100.00%9100.00%


static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) { dev_dbg(dev, "%s(): cmd=%08x\n", __func__, enabled); if (enabled) { at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM); at91_rtc_write_ier(AT91_RTC_ALARM); } else at91_rtc_write_idr(AT91_RTC_ALARM); return 0; }

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PersonTokensPropCommitsCommitProp
John Stultz3158.49%116.67%
Andrew Victor1528.30%116.67%
Jingoo Han35.66%116.67%
Johan Hovold23.77%116.67%
David Brownell11.89%116.67%
Jean-Christophe Plagniol-Villard11.89%116.67%
Total53100.00%6100.00%

/* * Provide additional RTC information in /proc/driver/rtc */
static int at91_rtc_proc(struct device *dev, struct seq_file *seq) { unsigned long imr = at91_rtc_read_imr(); seq_printf(seq, "update_IRQ\t: %s\n", (imr & AT91_RTC_ACKUPD) ? "yes" : "no"); seq_printf(seq, "periodic_IRQ\t: %s\n", (imr & AT91_RTC_SECEV) ? "yes" : "no"); return 0; }

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Andrew Victor5185.00%133.33%
Johan Hovold915.00%266.67%
Total60100.00%3100.00%

/* * IRQ handler for the RTC */
static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id) { struct platform_device *pdev = dev_id; struct rtc_device *rtc = platform_get_drvdata(pdev); unsigned int rtsr; unsigned long events = 0; int ret = IRQ_NONE; spin_lock(&suspended_lock); rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read_imr(); if (rtsr) { /* this interrupt is shared! Is it ours? */ if (rtsr & AT91_RTC_ALARM) events |= (RTC_AF | RTC_IRQF); if (rtsr & AT91_RTC_SECEV) { complete(&at91_rtc_upd_rdy); at91_rtc_write_idr(AT91_RTC_SECEV); } if (rtsr & AT91_RTC_ACKUPD) complete(&at91_rtc_updated); at91_rtc_write(AT91_RTC_SCCR, rtsr); /* clear status reg */ if (!suspended) { rtc_update_irq(rtc, 1, events); dev_dbg(&pdev->dev, "%s(): num=%ld, events=0x%02lx\n", __func__, events >> 8, events & 0x000000FF); } else { cached_events |= events; at91_rtc_write_idr(at91_rtc_imr); pm_system_wakeup(); } ret = IRQ_HANDLED; } spin_unlock(&suspended_lock); return ret; }

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Andrew Victor11964.32%112.50%
Boris Brezillon5429.19%225.00%
Jingoo Han63.24%112.50%
Jean-Christophe Plagniol-Villard21.08%112.50%
Johan Hovold21.08%112.50%
Harvey Harrison10.54%112.50%
Dan Carpenter10.54%112.50%
Total185100.00%8100.00%

static const struct at91_rtc_config at91rm9200_config = { }; static const struct at91_rtc_config at91sam9x5_config = { .use_shadow_imr = true, }; #ifdef CONFIG_OF static const struct of_device_id at91_rtc_dt_ids[] = { { .compatible = "atmel,at91rm9200-rtc", .data = &at91rm9200_config, }, { .compatible = "atmel,at91sam9x5-rtc", .data = &at91sam9x5_config, }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids); #endif
static const struct at91_rtc_config * at91_rtc_get_config(struct platform_device *pdev) { const struct of_device_id *match; if (pdev->dev.of_node) { match = of_match_node(at91_rtc_dt_ids, pdev->dev.of_node); if (!match) return NULL; return (const struct at91_rtc_config *)match->data; } return &at91rm9200_config; }

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Johan Hovold66100.00%1100.00%
Total66100.00%1100.00%

static const struct rtc_class_ops at91_rtc_ops = { .read_time = at91_rtc_readtime, .set_time = at91_rtc_settime, .read_alarm = at91_rtc_readalarm, .set_alarm = at91_rtc_setalarm, .proc = at91_rtc_proc, .alarm_irq_enable = at91_rtc_alarm_irq_enable, }; /* * Initialize and install RTC driver */
static int __init at91_rtc_probe(struct platform_device *pdev) { struct rtc_device *rtc; struct resource *regs; int ret = 0; at91_rtc_config = at91_rtc_get_config(pdev); if (!at91_rtc_config) return -ENODEV; regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!regs) { dev_err(&pdev->dev, "no mmio resource defined\n"); return -ENXIO; } irq = platform_get_irq(pdev, 0); if (irq < 0) { dev_err(&pdev->dev, "no irq resource defined\n"); return -ENXIO; } at91_rtc_regs = devm_ioremap(&pdev->dev, regs->start, resource_size(regs)); if (!at91_rtc_regs) { dev_err(&pdev->dev, "failed to map registers, aborting.\n"); return -ENOMEM; } rtc = devm_rtc_allocate_device(&pdev->dev); if (IS_ERR(rtc)) return PTR_ERR(rtc); platform_set_drvdata(pdev, rtc); sclk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(sclk)) return PTR_ERR(sclk); ret = clk_prepare_enable(sclk); if (ret) { dev_err(&pdev->dev, "Could not enable slow clock\n"); return ret; } at91_rtc_write(AT91_RTC_CR, 0); at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */ /* Disable all interrupts */ at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM | AT91_RTC_SECEV | AT91_RTC_TIMEV | AT91_RTC_CALEV); ret = devm_request_irq(&pdev->dev, irq, at91_rtc_interrupt, IRQF_SHARED | IRQF_COND_SUSPEND, "at91_rtc", pdev); if (ret) { dev_err(&pdev->dev, "IRQ %d already in use.\n", irq); goto err_clk; } /* cpu init code should really have flagged this device as * being wake-capable; if it didn't, do that here. */ if (!device_can_wakeup(&pdev->dev)) device_init_wakeup(&pdev->dev, 1); rtc->ops = &at91_rtc_ops; ret = rtc_register_device(rtc); if (ret) goto err_clk; /* enable SECEV interrupt in order to initialize at91_rtc_upd_rdy * completion. */ at91_rtc_write_ier(AT91_RTC_SECEV); dev_info(&pdev->dev, "AT91 Real Time Clock driver.\n"); return 0; err_clk: clk_disable_unprepare(sclk); return ret; }

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Jean-Christophe Plagniol-Villard10829.11%18.33%
Alexandre Belloni10728.84%216.67%
Andrew Victor8322.37%18.33%
David Brownell225.93%18.33%
Johan Hovold174.58%216.67%
Jingoo Han133.50%18.33%
Sachin Kamat123.23%18.33%
Boris Brezillon82.16%216.67%
Thomas Gleixner10.27%18.33%
Total371100.00%12100.00%

/* * Disable and remove the RTC driver */
static int __exit at91_rtc_remove(struct platform_device *pdev) { /* Disable all interrupts */ at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM | AT91_RTC_SECEV | AT91_RTC_TIMEV | AT91_RTC_CALEV); clk_disable_unprepare(sclk); return 0; }

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PersonTokensPropCommitsCommitProp
Andrew Victor2779.41%125.00%
Alexandre Belloni514.71%125.00%
Johan Hovold12.94%125.00%
David Brownell12.94%125.00%
Total34100.00%4100.00%


static void at91_rtc_shutdown(struct platform_device *pdev) { /* Disable all interrupts */ at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM | AT91_RTC_SECEV | AT91_RTC_TIMEV | AT91_RTC_CALEV); }

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Johan Hovold27100.00%1100.00%
Total27100.00%1100.00%

#ifdef CONFIG_PM_SLEEP /* AT91RM9200 RTC Power management control */
static int at91_rtc_suspend(struct device *dev) { /* this IRQ is shared with DBGU and other hardware which isn't * necessarily doing PM like we are... */ at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM); at91_rtc_imr = at91_rtc_read_imr() & (AT91_RTC_ALARM|AT91_RTC_SECEV); if (at91_rtc_imr) { if (device_may_wakeup(dev)) { unsigned long flags; enable_irq_wake(irq); spin_lock_irqsave(&suspended_lock, flags); suspended = true; spin_unlock_irqrestore(&suspended_lock, flags); } else { at91_rtc_write_idr(at91_rtc_imr); } } return 0; }

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PersonTokensPropCommitsCommitProp
Boris Brezillon2832.94%111.11%
David Brownell2731.76%222.22%
Andrew Victor1214.12%111.11%
Wenyou Yang78.24%111.11%
Johan Hovold67.06%222.22%
Nicolas Ferre44.71%111.11%
Jean-Christophe Plagniol-Villard11.18%111.11%
Total85100.00%9100.00%


static int at91_rtc_resume(struct device *dev) { struct rtc_device *rtc = dev_get_drvdata(dev); if (at91_rtc_imr) { if (device_may_wakeup(dev)) { unsigned long flags; spin_lock_irqsave(&suspended_lock, flags); if (cached_events) { rtc_update_irq(rtc, 1, cached_events); cached_events = 0; } suspended = false; spin_unlock_irqrestore(&suspended_lock, flags); disable_irq_wake(irq); } at91_rtc_write_ier(at91_rtc_imr); } return 0; }

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PersonTokensPropCommitsCommitProp
Boris Brezillon5559.78%114.29%
David Brownell2122.83%228.57%
Andrew Victor1213.04%114.29%
Johan Hovold33.26%228.57%
Jean-Christophe Plagniol-Villard11.09%114.29%
Total92100.00%7100.00%

#endif static SIMPLE_DEV_PM_OPS(at91_rtc_pm_ops, at91_rtc_suspend, at91_rtc_resume); static struct platform_driver at91_rtc_driver = { .remove = __exit_p(at91_rtc_remove), .shutdown = at91_rtc_shutdown, .driver = { .name = "at91_rtc", .pm = &at91_rtc_pm_ops, .of_match_table = of_match_ptr(at91_rtc_dt_ids), }, }; module_platform_driver_probe(at91_rtc_driver, at91_rtc_probe); MODULE_AUTHOR("Rick Bronson"); MODULE_DESCRIPTION("RTC driver for Atmel AT91RM9200"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:at91_rtc");

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Andrew Victor115950.04%12.63%
Johan Hovold38616.67%615.79%
Boris Brezillon1908.20%25.26%
Jean-Christophe Plagniol-Villard1536.61%25.26%
Alexandre Belloni1355.83%37.89%
David Brownell1154.97%615.79%
Jingoo Han482.07%37.89%
John Stultz361.55%12.63%
Adrian Bunk210.91%12.63%
Linus Pizunski200.86%12.63%
Sachin Kamat130.56%25.26%
Joachim Eastwood120.52%12.63%
Wenyou Yang70.30%12.63%
Kay Sievers50.22%12.63%
Harvey Harrison50.22%12.63%
Nicolas Ferre40.17%12.63%
Ben Dooks20.09%12.63%
Arnd Bergmann20.09%12.63%
Thomas Gleixner10.04%12.63%
Dan Carpenter10.04%12.63%
Lucas De Marchi10.04%12.63%
Total2316100.00%38100.00%
Directory: drivers/rtc
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