diff options
| -rw-r--r-- | arch/cris/arch-v10/drivers/pcf8563.c | 393 |
1 files changed, 220 insertions, 173 deletions
diff --git a/arch/cris/arch-v10/drivers/pcf8563.c b/arch/cris/arch-v10/drivers/pcf8563.c index c263b8232db..52103d16dc6 100644 --- a/arch/cris/arch-v10/drivers/pcf8563.c +++ b/arch/cris/arch-v10/drivers/pcf8563.c @@ -8,14 +8,13 @@ * 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 bute. + * automatically after each written or read byte. * - * Copyright (c) 2002, Axis Communications AB + * Copyright (c) 2002-2007, Axis Communications AB * All rights reserved. * * Author: Tobias Anderberg <tobiasa@axis.com>. * - * $Id: pcf8563.c,v 1.11 2005/03/07 13:13:07 starvik Exp $ */ #include <linux/module.h> @@ -27,19 +26,19 @@ #include <linux/ioctl.h> #include <linux/delay.h> #include <linux/bcd.h> -#include <linux/capability.h> +#include <linux/mutex.h> #include <asm/uaccess.h> #include <asm/system.h> #include <asm/io.h> -#include <asm/arch/svinto.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_MAJOR 121 /* Local major number. */ +#define DEVICE_NAME "rtc" /* Name which is registered in /proc/devices. */ #define PCF8563_NAME "PCF8563" -#define DRIVER_VERSION "$Revision: 1.11 $" +#define DRIVER_VERSION "$Revision: 1.24 $" /* I2C bus slave registers. */ #define RTC_I2C_READ 0xa3 @@ -49,71 +48,88 @@ #define rtc_read(x) i2c_readreg(RTC_I2C_READ, x) #define rtc_write(x,y) i2c_writereg(RTC_I2C_WRITE, x, y) -static DEFINE_SPINLOCK(rtc_lock); /* Protect state etc */ - +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 }; int pcf8563_ioctl(struct inode *, struct file *, unsigned int, unsigned long); +/* 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, .ioctl = pcf8563_ioctl, }; unsigned char -pcf8563_readreg(int reg) +pcf8563_readreg(int reg) { - unsigned char res = i2c_readreg(RTC_I2C_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_MONTH: - res = (res & 0x1f) - 1; /* PCF8563 returns month in range 1-12 */ - break; + 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) +pcf8563_writereg(int reg, unsigned char val) { -#ifdef CONFIG_ETRAX_RTC_READONLY - if (reg == RTC_CONTROL1 || (reg >= RTC_SECONDS && reg <= RTC_YEAR)) - return; -#endif - 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_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_mon = rtc_read(RTC_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_WARNING "%s: RTC Low Voltage - date/time is not reliable!\n", PCF8563_NAME); + 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 = BCD_TO_BIN(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_mon &= 0x1f; + tm->tm_year = BCD_TO_BIN(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; BCD_TO_BIN(tm->tm_sec); BCD_TO_BIN(tm->tm_min); @@ -126,17 +142,24 @@ get_rtc_time(struct rtc_time *tm) int __init pcf8563_init(void) { - int ret; - - if ((ret = i2c_init())) { - printk(KERN_CRIT "pcf8563_init: failed to init i2c\n"); - return ret; + 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, clear the - * Voltage Low bit, and resetting all alarms. + * clearing control1, control2 and clk freq and resetting + * all alarms. */ if (rtc_write(RTC_CONTROL1, 0x00) < 0) goto err; @@ -147,34 +170,36 @@ pcf8563_init(void) if (rtc_write(RTC_CLOCKOUT_FREQ, 0x00) < 0) goto err; - /* Clear the VL bit in the seconds register. */ - ret = rtc_read(RTC_SECONDS); - - if (rtc_write(RTC_SECONDS, (ret & 0x7f)) < 0) + if (rtc_write(RTC_TIMER_CONTROL, 0x03) < 0) goto err; - + /* Reset the alarms. */ - if (rtc_write(RTC_MINUTE_ALARM, 0x00) < 0) + if (rtc_write(RTC_MINUTE_ALARM, 0x80) < 0) goto err; - - if (rtc_write(RTC_HOUR_ALARM, 0x00) < 0) + + if (rtc_write(RTC_HOUR_ALARM, 0x80) < 0) goto err; - - if (rtc_write(RTC_DAY_ALARM, 0x00) < 0) + + if (rtc_write(RTC_DAY_ALARM, 0x80) < 0) goto err; - - if (rtc_write(RTC_WEEKDAY_ALARM, 0x00) < 0) + + if (rtc_write(RTC_WEEKDAY_ALARM, 0x80) < 0) goto err; - - /* Check for low voltage, and warn about it.. */ - if (rtc_read(RTC_SECONDS) & 0x80) - printk(KERN_WARNING "%s: RTC Low Voltage - date/time is not reliable!\n", PCF8563_NAME); - - return 0; + + /* 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); - return -1; + res = -1; + return res; } void __exit @@ -187,8 +212,8 @@ pcf8563_exit(void) * ioctl calls for this driver. Why return -ENOTTY upon error? Because * POSIX says so! */ -int -pcf8563_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg) +int pcf8563_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, + unsigned long arg) { /* Some sanity checks. */ if (_IOC_TYPE(cmd) != RTC_MAGIC) @@ -198,124 +223,146 @@ pcf8563_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned return -ENOTTY; switch (cmd) { - case RTC_RD_TIME: - { - struct rtc_time tm; - - spin_lock(&rtc_lock); - get_rtc_time(&tm); - - if (copy_to_user((struct rtc_time *) arg, &tm, sizeof(struct rtc_time))) { - spin_unlock(&rtc_lock); - return -EFAULT; - } - - spin_unlock(&rtc_lock); - return 0; - } - break; - case RTC_SET_TIME: - { -#ifdef CONFIG_ETRAX_RTC_READONLY - return -EPERM; -#else - int leap; - int century; - struct rtc_time tm; - - memset(&tm, 0, sizeof (struct rtc_time)); - if (!capable(CAP_SYS_TIME)) - return -EPERM; - - if (copy_from_user(&tm, (struct rtc_time *) arg, sizeof(struct rtc_time))) - return -EFAULT; - - /* Convert from struct tm to struct rtc_time. */ - tm.tm_year += 1900; - tm.tm_mon += 1; - - leap = ((tm.tm_mon == 2) && ((tm.tm_year % 4) == 0)) ? 1 : 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_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; - - BIN_TO_BCD(tm.tm_year); - BIN_TO_BCD(tm.tm_mday); - BIN_TO_BCD(tm.tm_hour); - BIN_TO_BCD(tm.tm_min); - BIN_TO_BCD(tm.tm_sec); - tm.tm_mon |= century; - - spin_lock(&rtc_lock); - - rtc_write(RTC_YEAR, tm.tm_year); - rtc_write(RTC_MONTH, tm.tm_mon); - 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); - - spin_unlock(&rtc_lock); - - return 0; -#endif /* !CONFIG_ETRAX_RTC_READONLY */ - } - - case RTC_VLOW_RD: - { - int vl_bit = 0; - - if (rtc_read(RTC_SECONDS) & 0x80) { - vl_bit = 1; - printk(KERN_WARNING "%s: RTC Voltage Low - reliable " - "date/time information is no longer guaranteed!\n", - PCF8563_NAME); - } - if (copy_to_user((int *) arg, &vl_bit, sizeof(int))) - return -EFAULT; - - return 0; - } + case RTC_RD_TIME: + { + struct rtc_time tm; - case RTC_VLOW_SET: - { - /* Clear the VL bit in the seconds register */ - int ret = rtc_read(RTC_SECONDS); + mutex_lock(&rtc_lock); + memset(&tm, 0, sizeof tm); + get_rtc_time(&tm); - rtc_write(RTC_SECONDS, (ret & 0x7F)); + if (copy_to_user((struct rtc_time *) arg, &tm, + sizeof tm)) { + spin_unlock(&rtc_lock); + return -EFAULT; + } + + mutex_unlock(&rtc_lock); - return 0; + 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; + + BIN_TO_BCD(tm.tm_year); + BIN_TO_BCD(tm.tm_mon); + BIN_TO_BCD(tm.tm_mday); + BIN_TO_BCD(tm.tm_hour); + BIN_TO_BCD(tm.tm_min); + BIN_TO_BCD(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); } - default: - return -ENOTTY; + 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 int __init -pcf8563_register(void) +static int __init pcf8563_register(void) { - pcf8563_init(); + 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 number %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); - return 0; + 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); |