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Release 4.14 drivers/rtc/rtc-x1205.c

Directory: drivers/rtc
/*
 * An i2c driver for the Xicor/Intersil X1205 RTC
 * Copyright 2004 Karen Spearel
 * Copyright 2005 Alessandro Zummo
 *
 * please send all reports to:
 *      Karen Spearel <kas111 at gmail dot com>
 *      Alessandro Zummo <a.zummo@towertech.it>
 *
 * based on a lot of other RTC drivers.
 *
 * Information and datasheet:
 * http://www.intersil.com/cda/deviceinfo/0,1477,X1205,00.html
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/i2c.h>
#include <linux/bcd.h>
#include <linux/rtc.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/bitops.h>

/* offsets into CCR area */


#define CCR_SEC			0

#define CCR_MIN			1

#define CCR_HOUR		2

#define CCR_MDAY		3

#define CCR_MONTH		4

#define CCR_YEAR		5

#define CCR_WDAY		6

#define CCR_Y2K			7


#define X1205_REG_SR		0x3F	
/* status register */

#define X1205_REG_Y2K		0x37

#define X1205_REG_DW		0x36

#define X1205_REG_YR		0x35

#define X1205_REG_MO		0x34

#define X1205_REG_DT		0x33

#define X1205_REG_HR		0x32

#define X1205_REG_MN		0x31

#define X1205_REG_SC		0x30

#define X1205_REG_DTR		0x13

#define X1205_REG_ATR		0x12

#define X1205_REG_INT		0x11

#define X1205_REG_0		0x10

#define X1205_REG_Y2K1		0x0F

#define X1205_REG_DWA1		0x0E

#define X1205_REG_YRA1		0x0D

#define X1205_REG_MOA1		0x0C

#define X1205_REG_DTA1		0x0B

#define X1205_REG_HRA1		0x0A

#define X1205_REG_MNA1		0x09

#define X1205_REG_SCA1		0x08

#define X1205_REG_Y2K0		0x07

#define X1205_REG_DWA0		0x06

#define X1205_REG_YRA0		0x05

#define X1205_REG_MOA0		0x04

#define X1205_REG_DTA0		0x03

#define X1205_REG_HRA0		0x02

#define X1205_REG_MNA0		0x01

#define X1205_REG_SCA0		0x00


#define X1205_CCR_BASE		0x30	
/* Base address of CCR */

#define X1205_ALM0_BASE		0x00	
/* Base address of ALARM0 */


#define X1205_SR_RTCF		0x01	
/* Clock failure */

#define X1205_SR_WEL		0x02	
/* Write Enable Latch */

#define X1205_SR_RWEL		0x04	
/* Register Write Enable */

#define X1205_SR_AL0		0x20	
/* Alarm 0 match */


#define X1205_DTR_DTR0		0x01

#define X1205_DTR_DTR1		0x02

#define X1205_DTR_DTR2		0x04


#define X1205_HR_MIL		0x80	
/* Set in ccr.hour for 24 hr mode */


#define X1205_INT_AL0E		0x20	
/* Alarm 0 enable */


static struct i2c_driver x1205_driver;

/*
 * In the routines that deal directly with the x1205 hardware, we use
 * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch
 * Epoch is initialized as 2000. Time is set to UTC.
 */

static int x1205_get_datetime(struct i2c_client *client, struct rtc_time *tm, unsigned char reg_base) { unsigned char dt_addr[2] = { 0, reg_base }; unsigned char buf[8]; int i; struct i2c_msg msgs[] = { {/* setup read ptr */ .addr = client->addr, .len = 2, .buf = dt_addr }, {/* read date */ .addr = client->addr, .flags = I2C_M_RD, .len = 8, .buf = buf }, }; /* read date registers */ if (i2c_transfer(client->adapter, &msgs[0], 2) != 2) { dev_err(&client->dev, "%s: read error\n", __func__); return -EIO; } dev_dbg(&client->dev, "%s: raw read data - sec=%02x, min=%02x, hr=%02x, " "mday=%02x, mon=%02x, year=%02x, wday=%02x, y2k=%02x\n", __func__, buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6], buf[7]); /* Mask out the enable bits if these are alarm registers */ if (reg_base < X1205_CCR_BASE) for (i = 0; i <= 4; i++) buf[i] &= 0x7F; tm->tm_sec = bcd2bin(buf[CCR_SEC]); tm->tm_min = bcd2bin(buf[CCR_MIN]); tm->tm_hour = bcd2bin(buf[CCR_HOUR] & 0x3F); /* hr is 0-23 */ tm->tm_mday = bcd2bin(buf[CCR_MDAY]); tm->tm_mon = bcd2bin(buf[CCR_MONTH]) - 1; /* mon is 0-11 */ tm->tm_year = bcd2bin(buf[CCR_YEAR]) + (bcd2bin(buf[CCR_Y2K]) * 100) - 1900; tm->tm_wday = buf[CCR_WDAY]; dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, " "mday=%d, mon=%d, year=%d, wday=%d\n", __func__, tm->tm_sec, tm->tm_min, tm->tm_hour, tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); return 0; }

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Alessandro Zummo29482.12%120.00%
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Adrian Bunk71.96%120.00%
Harvey Harrison30.84%120.00%
Total358100.00%5100.00%


static int x1205_get_status(struct i2c_client *client, unsigned char *sr) { static unsigned char sr_addr[2] = { 0, X1205_REG_SR }; struct i2c_msg msgs[] = { { /* setup read ptr */ .addr = client->addr, .len = 2, .buf = sr_addr }, { /* read status */ .addr = client->addr, .flags = I2C_M_RD, .len = 1, .buf = sr }, }; /* read status register */ if (i2c_transfer(client->adapter, &msgs[0], 2) != 2) { dev_err(&client->dev, "%s: read error\n", __func__); return -EIO; } return 0; }

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Alessandro Zummo9879.67%133.33%
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Harvey Harrison10.81%133.33%
Total123100.00%3100.00%


static int x1205_set_datetime(struct i2c_client *client, struct rtc_time *tm, u8 reg_base, unsigned char alm_enable) { int i, xfer; unsigned char rdata[10] = { 0, reg_base }; unsigned char *buf = rdata + 2; static const unsigned char wel[3] = { 0, X1205_REG_SR, X1205_SR_WEL }; static const unsigned char rwel[3] = { 0, X1205_REG_SR, X1205_SR_WEL | X1205_SR_RWEL }; static const unsigned char diswe[3] = { 0, X1205_REG_SR, 0 }; dev_dbg(&client->dev, "%s: sec=%d min=%d hour=%d mday=%d mon=%d year=%d wday=%d\n", __func__, tm->tm_sec, tm->tm_min, tm->tm_hour, tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); buf[CCR_SEC] = bin2bcd(tm->tm_sec); buf[CCR_MIN] = bin2bcd(tm->tm_min); /* set hour and 24hr bit */ buf[CCR_HOUR] = bin2bcd(tm->tm_hour) | X1205_HR_MIL; buf[CCR_MDAY] = bin2bcd(tm->tm_mday); /* month, 1 - 12 */ buf[CCR_MONTH] = bin2bcd(tm->tm_mon + 1); /* year, since the rtc epoch*/ buf[CCR_YEAR] = bin2bcd(tm->tm_year % 100); buf[CCR_WDAY] = tm->tm_wday & 0x07; buf[CCR_Y2K] = bin2bcd((tm->tm_year + 1900) / 100); /* If writing alarm registers, set compare bits on registers 0-4 */ if (reg_base < X1205_CCR_BASE) for (i = 0; i <= 4; i++) buf[i] |= 0x80; /* this sequence is required to unlock the chip */ xfer = i2c_master_send(client, wel, 3); if (xfer != 3) { dev_err(&client->dev, "%s: wel - %d\n", __func__, xfer); return -EIO; } xfer = i2c_master_send(client, rwel, 3); if (xfer != 3) { dev_err(&client->dev, "%s: rwel - %d\n", __func__, xfer); return -EIO; } xfer = i2c_master_send(client, rdata, sizeof(rdata)); if (xfer != sizeof(rdata)) { dev_err(&client->dev, "%s: result=%d addr=%02x, data=%02x\n", __func__, xfer, rdata[1], rdata[2]); return -EIO; } /* If we wrote to the nonvolatile region, wait 10msec for write cycle*/ if (reg_base < X1205_CCR_BASE) { unsigned char al0e[3] = { 0, X1205_REG_INT, 0 }; msleep(10); /* ...and set or clear the AL0E bit in the INT register */ /* Need to set RWEL again as the write has cleared it */ xfer = i2c_master_send(client, rwel, 3); if (xfer != 3) { dev_err(&client->dev, "%s: aloe rwel - %d\n", __func__, xfer); return -EIO; } if (alm_enable) al0e[2] = X1205_INT_AL0E; xfer = i2c_master_send(client, al0e, 3); if (xfer != 3) { dev_err(&client->dev, "%s: al0e - %d\n", __func__, xfer); return -EIO; } /* and wait 10msec again for this write to complete */ msleep(10); } /* disable further writes */ xfer = i2c_master_send(client, diswe, 3); if (xfer != 3) { dev_err(&client->dev, "%s: diswe - %d\n", __func__, xfer); return -EIO; } return 0; }

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Michael Hamel16629.07%114.29%
Johannes Weiner386.65%228.57%
Sachin Kamat122.10%114.29%
Adrian Bunk71.23%114.29%
Harvey Harrison50.88%114.29%
Total571100.00%7100.00%


static int x1205_fix_osc(struct i2c_client *client) { int err; struct rtc_time tm; memset(&tm, 0, sizeof(tm)); err = x1205_set_datetime(client, &tm, X1205_CCR_BASE, 0); if (err < 0) dev_err(&client->dev, "unable to restart the oscillator\n"); return err; }

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Alessandro Zummo4875.00%133.33%
Johannes Weiner1015.62%133.33%
Michael Hamel69.38%133.33%
Total64100.00%3100.00%


static int x1205_get_dtrim(struct i2c_client *client, int *trim) { unsigned char dtr; static unsigned char dtr_addr[2] = { 0, X1205_REG_DTR }; struct i2c_msg msgs[] = { { /* setup read ptr */ .addr = client->addr, .len = 2, .buf = dtr_addr }, { /* read dtr */ .addr = client->addr, .flags = I2C_M_RD, .len = 1, .buf = &dtr }, }; /* read dtr register */ if (i2c_transfer(client->adapter, &msgs[0], 2) != 2) { dev_err(&client->dev, "%s: read error\n", __func__); return -EIO; } dev_dbg(&client->dev, "%s: raw dtr=%x\n", __func__, dtr); *trim = 0; if (dtr & X1205_DTR_DTR0) *trim += 20; if (dtr & X1205_DTR_DTR1) *trim += 10; if (dtr & X1205_DTR_DTR2) *trim = -*trim; return 0; }

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Harvey Harrison21.10%133.33%
Total181100.00%3100.00%


static int x1205_get_atrim(struct i2c_client *client, int *trim) { s8 atr; static unsigned char atr_addr[2] = { 0, X1205_REG_ATR }; struct i2c_msg msgs[] = { {/* setup read ptr */ .addr = client->addr, .len = 2, .buf = atr_addr }, {/* read atr */ .addr = client->addr, .flags = I2C_M_RD, .len = 1, .buf = &atr }, }; /* read atr register */ if (i2c_transfer(client->adapter, &msgs[0], 2) != 2) { dev_err(&client->dev, "%s: read error\n", __func__); return -EIO; } dev_dbg(&client->dev, "%s: raw atr=%x\n", __func__, atr); /* atr is a two's complement value on 6 bits, * perform sign extension. The formula is * Catr = (atr * 0.25pF) + 11.00pF. */ atr = sign_extend32(atr, 5); dev_dbg(&client->dev, "%s: raw atr=%x (%d)\n", __func__, atr, atr); *trim = (atr * 250) + 11000; dev_dbg(&client->dev, "%s: real=%d\n", __func__, *trim); return 0; }

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Alessandro Zummo15882.29%125.00%
Shubhrajyoti Datta2412.50%125.00%
Martin Kepplinger63.12%125.00%
Harvey Harrison42.08%125.00%
Total192100.00%4100.00%

struct x1205_limit { unsigned char reg, mask, min, max; };
static int x1205_validate_client(struct i2c_client *client) { int i, xfer; /* Probe array. We will read the register at the specified * address and check if the given bits are zero. */ static const unsigned char probe_zero_pattern[] = { /* register, mask */ X1205_REG_SR, 0x18, X1205_REG_DTR, 0xF8, X1205_REG_ATR, 0xC0, X1205_REG_INT, 0x18, X1205_REG_0, 0xFF, }; static const struct x1205_limit probe_limits_pattern[] = { /* register, mask, min, max */ { X1205_REG_Y2K, 0xFF, 19, 20 }, { X1205_REG_DW, 0xFF, 0, 6 }, { X1205_REG_YR, 0xFF, 0, 99 }, { X1205_REG_MO, 0xFF, 0, 12 }, { X1205_REG_DT, 0xFF, 0, 31 }, { X1205_REG_HR, 0x7F, 0, 23 }, { X1205_REG_MN, 0xFF, 0, 59 }, { X1205_REG_SC, 0xFF, 0, 59 }, { X1205_REG_Y2K1, 0xFF, 19, 20 }, { X1205_REG_Y2K0, 0xFF, 19, 20 }, }; /* check that registers have bits a 0 where expected */ for (i = 0; i < ARRAY_SIZE(probe_zero_pattern); i += 2) { unsigned char buf; unsigned char addr[2] = { 0, probe_zero_pattern[i] }; struct i2c_msg msgs[2] = { { .addr = client->addr, .len = 2, .buf = addr }, { .addr = client->addr, .flags = I2C_M_RD, .len = 1, .buf = &buf }, }; xfer = i2c_transfer(client->adapter, msgs, 2); if (xfer != 2) { dev_err(&client->dev, "%s: could not read register %x\n", __func__, probe_zero_pattern[i]); return -EIO; } if ((buf & probe_zero_pattern[i+1]) != 0) { dev_err(&client->dev, "%s: register=%02x, zero pattern=%d, value=%x\n", __func__, probe_zero_pattern[i], i, buf); return -ENODEV; } } /* check limits (only registers with bcd values) */ for (i = 0; i < ARRAY_SIZE(probe_limits_pattern); i++) { unsigned char reg, value; unsigned char addr[2] = { 0, probe_limits_pattern[i].reg }; struct i2c_msg msgs[2] = { { .addr = client->addr, .len = 2, .buf = addr }, { .addr = client->addr, .flags = I2C_M_RD, .len = 1, .buf = &reg }, }; xfer = i2c_transfer(client->adapter, msgs, 2); if (xfer != 2) { dev_err(&client->dev, "%s: could not read register %x\n", __func__, probe_limits_pattern[i].reg); return -EIO; } value = bcd2bin(reg & probe_limits_pattern[i].mask); if (value > probe_limits_pattern[i].max || value < probe_limits_pattern[i].min) { dev_dbg(&client->dev, "%s: register=%x, lim pattern=%d, value=%d\n", __func__, probe_limits_pattern[i].reg, i, value); return -ENODEV; } } return 0; }

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Alessandro Zummo48589.81%120.00%
Shubhrajyoti Datta427.78%120.00%
Sachin Kamat81.48%120.00%
Harvey Harrison40.74%120.00%
Adrian Bunk10.19%120.00%
Total540100.00%5100.00%


static int x1205_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) { int err; unsigned char intreg, status; static unsigned char int_addr[2] = { 0, X1205_REG_INT }; struct i2c_client *client = to_i2c_client(dev); struct i2c_msg msgs[] = { { /* setup read ptr */ .addr = client->addr, .len = 2, .buf = int_addr }, {/* read INT register */ .addr = client->addr, .flags = I2C_M_RD, .len = 1, .buf = &intreg }, }; /* read interrupt register and status register */ if (i2c_transfer(client->adapter, &msgs[0], 2) != 2) { dev_err(&client->dev, "%s: read error\n", __func__); return -EIO; } err = x1205_get_status(client, &status); if (err == 0) { alrm->pending = (status & X1205_SR_AL0) ? 1 : 0; alrm->enabled = (intreg & X1205_INT_AL0E) ? 1 : 0; err = x1205_get_datetime(client, &alrm->time, X1205_ALM0_BASE); } return err; }

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Michael Hamel15073.89%133.33%
Alessandro Zummo2914.29%133.33%
Shubhrajyoti Datta2411.82%133.33%
Total203100.00%3100.00%


static int x1205_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) { return x1205_set_datetime(to_i2c_client(dev), &alrm->time, X1205_ALM0_BASE, alrm->enabled); }

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Alessandro Zummo3288.89%150.00%
Michael Hamel411.11%150.00%
Total36100.00%2100.00%


static int x1205_rtc_read_time(struct device *dev, struct rtc_time *tm) { return x1205_get_datetime(to_i2c_client(dev), tm, X1205_CCR_BASE); }

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static int x1205_rtc_set_time(struct device *dev, struct rtc_time *tm) { return x1205_set_datetime(to_i2c_client(dev), tm, X1205_CCR_BASE, 0); }

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Michael Hamel26.45%150.00%
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static int x1205_rtc_proc(struct device *dev, struct seq_file *seq) { int err, dtrim, atrim; err = x1205_get_dtrim(to_i2c_client(dev), &dtrim); if (!err) seq_printf(seq, "digital_trim\t: %d ppm\n", dtrim); err = x1205_get_atrim(to_i2c_client(dev), &atrim); if (!err) seq_printf(seq, "analog_trim\t: %d.%02d pF\n", atrim / 1000, atrim % 1000); return 0; }

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Sachin Kamat1011.63%150.00%
Total86100.00%2100.00%

static const struct rtc_class_ops x1205_rtc_ops = { .proc = x1205_rtc_proc, .read_time = x1205_rtc_read_time, .set_time = x1205_rtc_set_time, .read_alarm = x1205_rtc_read_alarm, .set_alarm = x1205_rtc_set_alarm, };
static ssize_t x1205_sysfs_show_atrim(struct device *dev, struct device_attribute *attr, char *buf) { int err, atrim; err = x1205_get_atrim(to_i2c_client(dev), &atrim); if (err) return err; return sprintf(buf, "%d.%02d pF\n", atrim / 1000, atrim % 1000); }

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static DEVICE_ATTR(atrim, S_IRUGO, x1205_sysfs_show_atrim, NULL);
static ssize_t x1205_sysfs_show_dtrim(struct device *dev, struct device_attribute *attr, char *buf) { int err, dtrim; err = x1205_get_dtrim(to_i2c_client(dev), &dtrim); if (err) return err; return sprintf(buf, "%d ppm\n", dtrim); }

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static DEVICE_ATTR(dtrim, S_IRUGO, x1205_sysfs_show_dtrim, NULL);
static int x1205_sysfs_register(struct device *dev) { int err; err = device_create_file(dev, &dev_attr_atrim); if (err) return err; err = device_create_file(dev, &dev_attr_dtrim); if (err) device_remove_file(dev, &dev_attr_atrim); return err; }

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static void x1205_sysfs_unregister(struct device *dev) { device_remove_file(dev, &dev_attr_atrim); device_remove_file(dev, &dev_attr_dtrim); }

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Alessandro Zummo27100.00%1100.00%
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static int x1205_probe(struct i2c_client *client, const struct i2c_device_id *id) { int err = 0; unsigned char sr; struct rtc_device *rtc; dev_dbg(&client->dev, "%s\n", __func__); if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) return -ENODEV; if (x1205_validate_client(client) < 0) return -ENODEV; rtc = devm_rtc_device_register(&client->dev, x1205_driver.driver.name, &x1205_rtc_ops, THIS_MODULE); if (IS_ERR(rtc)) return PTR_ERR(rtc); i2c_set_clientdata(client, rtc); /* Check for power failures and eventually enable the osc */ err = x1205_get_status(client, &sr); if (!err) { if (sr & X1205_SR_RTCF) { dev_err(&client->dev, "power failure detected, " "please set the clock\n"); udelay(50); x1205_fix_osc(client); } } else { dev_err(&client->dev, "couldn't read status\n"); } err = x1205_sysfs_register(&client->dev); if (err) dev_err(&client->dev, "Unable to create sysfs entries\n"); return 0; }

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Alessandro Zummo17286.00%333.33%
Jean Delvare73.50%222.22%
Sachin Kamat73.50%111.11%
Jingoo Han73.50%111.11%
Jeff Garzik63.00%111.11%
Lucas De Marchi10.50%111.11%
Total200100.00%9100.00%


static int x1205_remove(struct i2c_client *client) { x1205_sysfs_unregister(&client->dev); return 0; }

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static const struct i2c_device_id x1205_id[] = { { "x1205", 0 }, { } }; MODULE_DEVICE_TABLE(i2c, x1205_id); static struct i2c_driver x1205_driver = { .driver = { .name = "rtc-x1205", }, .probe = x1205_probe, .remove = x1205_remove, .id_table = x1205_id, }; module_i2c_driver(x1205_driver); MODULE_AUTHOR( "Karen Spearel <kas111 at gmail dot com>, " "Alessandro Zummo <a.zummo@towertech.it>"); MODULE_DESCRIPTION("Xicor/Intersil X1205 RTC driver"); MODULE_LICENSE("GPL");

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Alessandro Zummo249777.76%418.18%
Michael Hamel36811.46%14.55%
Shubhrajyoti Datta1625.05%14.55%
Johannes Weiner481.49%313.64%
Sachin Kamat381.18%14.55%
Jean Delvare361.12%313.64%
Harvey Harrison190.59%14.55%
Adrian Bunk150.47%14.55%
Martin Kepplinger90.28%14.55%
Jingoo Han70.22%14.55%
Jeff Garzik60.19%14.55%
Paul Gortmaker30.09%14.55%
David Brownell10.03%14.55%
Lucas De Marchi10.03%14.55%
Axel Lin10.03%14.55%
Total3211100.00%22100.00%
Directory: drivers/rtc
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