+++ /dev/null
-/*
- * PCF8563 RTC
- *
- * From Phillips' datasheet:
- *
- * The PCF8563 is a CMOS real-time clock/calendar optimized for low power
- * consumption. A programmable clock output, interrupt output and voltage
- * low detector are also provided. All address and data are transferred
- * serially via two-line bidirectional I2C-bus. Maximum bus speed is
- * 400 kbits/s. The built-in word address register is incremented
- * automatically after each written or read byte.
- *
- * Copyright (c) 2002-2007, Axis Communications AB
- * All rights reserved.
- *
- * Author: Tobias Anderberg <tobiasa@axis.com>.
- *
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/types.h>
-#include <linux/sched.h>
-#include <linux/init.h>
-#include <linux/fs.h>
-#include <linux/ioctl.h>
-#include <linux/delay.h>
-#include <linux/bcd.h>
-#include <linux/mutex.h>
-
-#include <asm/uaccess.h>
-#include <asm/system.h>
-#include <asm/io.h>
-#include <asm/rtc.h>
-
-#include "i2c.h"
-
-#define PCF8563_MAJOR 121 /* Local major number. */
-#define DEVICE_NAME "rtc" /* Name which is registered in /proc/devices. */
-#define PCF8563_NAME "PCF8563"
-#define DRIVER_VERSION "$Revision: 1.17 $"
-
-/* Two simple wrapper macros, saves a few keystrokes. */
-#define rtc_read(x) i2c_readreg(RTC_I2C_READ, x)
-#define rtc_write(x,y) i2c_writereg(RTC_I2C_WRITE, x, y)
-
-static DEFINE_MUTEX(pcf8563_mutex);
-static DEFINE_MUTEX(rtc_lock); /* Protect state etc */
-
-static const unsigned char days_in_month[] =
- { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
-
-static long pcf8563_unlocked_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
-
-/* Cache VL bit value read at driver init since writing the RTC_SECOND
- * register clears the VL status.
- */
-static int voltage_low;
-
-static const struct file_operations pcf8563_fops = {
- .owner = THIS_MODULE,
- .unlocked_ioctl = pcf8563_unlocked_ioctl,
- .llseek = noop_llseek,
-};
-
-unsigned char
-pcf8563_readreg(int reg)
-{
- unsigned char res = rtc_read(reg);
-
- /* The PCF8563 does not return 0 for unimplemented bits. */
- switch (reg) {
- case RTC_SECONDS:
- case RTC_MINUTES:
- res &= 0x7F;
- break;
- case RTC_HOURS:
- case RTC_DAY_OF_MONTH:
- res &= 0x3F;
- break;
- case RTC_WEEKDAY:
- res &= 0x07;
- break;
- case RTC_MONTH:
- res &= 0x1F;
- break;
- case RTC_CONTROL1:
- res &= 0xA8;
- break;
- case RTC_CONTROL2:
- res &= 0x1F;
- break;
- case RTC_CLOCKOUT_FREQ:
- case RTC_TIMER_CONTROL:
- res &= 0x83;
- break;
- }
- return res;
-}
-
-void
-pcf8563_writereg(int reg, unsigned char val)
-{
- rtc_write(reg, val);
-}
-
-void
-get_rtc_time(struct rtc_time *tm)
-{
- tm->tm_sec = rtc_read(RTC_SECONDS);
- tm->tm_min = rtc_read(RTC_MINUTES);
- tm->tm_hour = rtc_read(RTC_HOURS);
- tm->tm_mday = rtc_read(RTC_DAY_OF_MONTH);
- tm->tm_wday = rtc_read(RTC_WEEKDAY);
- tm->tm_mon = rtc_read(RTC_MONTH);
- tm->tm_year = rtc_read(RTC_YEAR);
-
- if (tm->tm_sec & 0x80) {
- printk(KERN_ERR "%s: RTC Voltage Low - reliable date/time "
- "information is no longer guaranteed!\n", PCF8563_NAME);
- }
-
- tm->tm_year = bcd2bin(tm->tm_year) +
- ((tm->tm_mon & 0x80) ? 100 : 0);
- tm->tm_sec &= 0x7F;
- tm->tm_min &= 0x7F;
- tm->tm_hour &= 0x3F;
- tm->tm_mday &= 0x3F;
- tm->tm_wday &= 0x07; /* Not coded in BCD. */
- tm->tm_mon &= 0x1F;
-
- tm->tm_sec = bcd2bin(tm->tm_sec);
- tm->tm_min = bcd2bin(tm->tm_min);
- tm->tm_hour = bcd2bin(tm->tm_hour);
- tm->tm_mday = bcd2bin(tm->tm_mday);
- tm->tm_mon = bcd2bin(tm->tm_mon);
- tm->tm_mon--; /* Month is 1..12 in RTC but 0..11 in linux */
-}
-
-int __init
-pcf8563_init(void)
-{
- static int res;
- static int first = 1;
-
- if (!first)
- return res;
- first = 0;
-
- /* Initiate the i2c protocol. */
- res = i2c_init();
- if (res < 0) {
- printk(KERN_CRIT "pcf8563_init: Failed to init i2c.\n");
- return res;
- }
-
- /*
- * First of all we need to reset the chip. This is done by
- * clearing control1, control2 and clk freq and resetting
- * all alarms.
- */
- if (rtc_write(RTC_CONTROL1, 0x00) < 0)
- goto err;
-
- if (rtc_write(RTC_CONTROL2, 0x00) < 0)
- goto err;
-
- if (rtc_write(RTC_CLOCKOUT_FREQ, 0x00) < 0)
- goto err;
-
- if (rtc_write(RTC_TIMER_CONTROL, 0x03) < 0)
- goto err;
-
- /* Reset the alarms. */
- if (rtc_write(RTC_MINUTE_ALARM, 0x80) < 0)
- goto err;
-
- if (rtc_write(RTC_HOUR_ALARM, 0x80) < 0)
- goto err;
-
- if (rtc_write(RTC_DAY_ALARM, 0x80) < 0)
- goto err;
-
- if (rtc_write(RTC_WEEKDAY_ALARM, 0x80) < 0)
- goto err;
-
- /* Check for low voltage, and warn about it. */
- if (rtc_read(RTC_SECONDS) & 0x80) {
- voltage_low = 1;
- printk(KERN_WARNING "%s: RTC Voltage Low - reliable "
- "date/time information is no longer guaranteed!\n",
- PCF8563_NAME);
- }
-
- return res;
-
-err:
- printk(KERN_INFO "%s: Error initializing chip.\n", PCF8563_NAME);
- res = -1;
- return res;
-}
-
-void __exit
-pcf8563_exit(void)
-{
- unregister_chrdev(PCF8563_MAJOR, DEVICE_NAME);
-}
-
-/*
- * ioctl calls for this driver. Why return -ENOTTY upon error? Because
- * POSIX says so!
- */
-static int pcf8563_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
-{
- /* Some sanity checks. */
- if (_IOC_TYPE(cmd) != RTC_MAGIC)
- return -ENOTTY;
-
- if (_IOC_NR(cmd) > RTC_MAX_IOCTL)
- return -ENOTTY;
-
- switch (cmd) {
- case RTC_RD_TIME:
- {
- struct rtc_time tm;
-
- mutex_lock(&rtc_lock);
- memset(&tm, 0, sizeof tm);
- get_rtc_time(&tm);
-
- if (copy_to_user((struct rtc_time *) arg, &tm,
- sizeof tm)) {
- mutex_unlock(&rtc_lock);
- return -EFAULT;
- }
-
- mutex_unlock(&rtc_lock);
-
- return 0;
- }
- case RTC_SET_TIME:
- {
- int leap;
- int year;
- int century;
- struct rtc_time tm;
-
- memset(&tm, 0, sizeof tm);
- if (!capable(CAP_SYS_TIME))
- return -EPERM;
-
- if (copy_from_user(&tm, (struct rtc_time *) arg,
- sizeof tm))
- return -EFAULT;
-
- /* Convert from struct tm to struct rtc_time. */
- tm.tm_year += 1900;
- tm.tm_mon += 1;
-
- /*
- * Check if tm.tm_year is a leap year. A year is a leap
- * year if it is divisible by 4 but not 100, except
- * that years divisible by 400 _are_ leap years.
- */
- year = tm.tm_year;
- leap = (tm.tm_mon == 2) &&
- ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0);
-
- /* Perform some sanity checks. */
- if ((tm.tm_year < 1970) ||
- (tm.tm_mon > 12) ||
- (tm.tm_mday == 0) ||
- (tm.tm_mday > days_in_month[tm.tm_mon] + leap) ||
- (tm.tm_wday >= 7) ||
- (tm.tm_hour >= 24) ||
- (tm.tm_min >= 60) ||
- (tm.tm_sec >= 60))
- return -EINVAL;
-
- century = (tm.tm_year >= 2000) ? 0x80 : 0;
- tm.tm_year = tm.tm_year % 100;
-
- tm.tm_year = bin2bcd(tm.tm_year);
- tm.tm_mon = bin2bcd(tm.tm_mon);
- tm.tm_mday = bin2bcd(tm.tm_mday);
- tm.tm_hour = bin2bcd(tm.tm_hour);
- tm.tm_min = bin2bcd(tm.tm_min);
- tm.tm_sec = bin2bcd(tm.tm_sec);
- tm.tm_mon |= century;
-
- mutex_lock(&rtc_lock);
-
- rtc_write(RTC_YEAR, tm.tm_year);
- rtc_write(RTC_MONTH, tm.tm_mon);
- rtc_write(RTC_WEEKDAY, tm.tm_wday); /* Not coded in BCD. */
- rtc_write(RTC_DAY_OF_MONTH, tm.tm_mday);
- rtc_write(RTC_HOURS, tm.tm_hour);
- rtc_write(RTC_MINUTES, tm.tm_min);
- rtc_write(RTC_SECONDS, tm.tm_sec);
-
- mutex_unlock(&rtc_lock);
-
- return 0;
- }
- case RTC_VL_READ:
- if (voltage_low)
- printk(KERN_ERR "%s: RTC Voltage Low - "
- "reliable date/time information is no "
- "longer guaranteed!\n", PCF8563_NAME);
-
- if (copy_to_user((int *) arg, &voltage_low, sizeof(int)))
- return -EFAULT;
- return 0;
-
- case RTC_VL_CLR:
- {
- /* Clear the VL bit in the seconds register in case
- * the time has not been set already (which would
- * have cleared it). This does not really matter
- * because of the cached voltage_low value but do it
- * anyway for consistency. */
-
- int ret = rtc_read(RTC_SECONDS);
-
- rtc_write(RTC_SECONDS, (ret & 0x7F));
-
- /* Clear the cached value. */
- voltage_low = 0;
-
- return 0;
- }
- default:
- return -ENOTTY;
- }
-
- return 0;
-}
-
-static long pcf8563_unlocked_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
-{
- int ret;
-
- mutex_lock(&pcf8563_mutex);
- return pcf8563_ioctl(filp, cmd, arg);
- mutex_unlock(&pcf8563_mutex);
-
- return ret;
-}
-
-static int __init pcf8563_register(void)
-{
- if (pcf8563_init() < 0) {
- printk(KERN_INFO "%s: Unable to initialize Real-Time Clock "
- "Driver, %s\n", PCF8563_NAME, DRIVER_VERSION);
- return -1;
- }
-
- if (register_chrdev(PCF8563_MAJOR, DEVICE_NAME, &pcf8563_fops) < 0) {
- printk(KERN_INFO "%s: Unable to get major numer %d for RTC "
- "device.\n", PCF8563_NAME, PCF8563_MAJOR);
- return -1;
- }
-
- printk(KERN_INFO "%s Real-Time Clock Driver, %s\n", PCF8563_NAME,
- DRIVER_VERSION);
-
- /* Check for low voltage, and warn about it. */
- if (voltage_low) {
- printk(KERN_WARNING "%s: RTC Voltage Low - reliable date/time "
- "information is no longer guaranteed!\n", PCF8563_NAME);
- }
-
- return 0;
-}
-
-module_init(pcf8563_register);
-module_exit(pcf8563_exit);
git.openpandora.org / pandora-kernel.git / commitdiff