diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/cris/arch-v10/drivers/pcf8563.c |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/cris/arch-v10/drivers/pcf8563.c')
-rw-r--r-- | arch/cris/arch-v10/drivers/pcf8563.c | 313 |
1 files changed, 313 insertions, 0 deletions
diff --git a/arch/cris/arch-v10/drivers/pcf8563.c b/arch/cris/arch-v10/drivers/pcf8563.c new file mode 100644 index 00000000000..b3dfdf7b8fc --- /dev/null +++ b/arch/cris/arch-v10/drivers/pcf8563.c @@ -0,0 +1,313 @@ +/* + * PCF8563 RTC + * + * From Phillips' datasheet: + * + * The PCF8563 is a CMOS real-time clock/calendar optimized for low power + * consumption. A programmable clock output, interupt 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 bute. + * + * Copyright (c) 2002, Axis Communications AB + * All rights reserved. + * + * Author: Tobias Anderberg <tobiasa@axis.com>. + * + * $Id: pcf8563.c,v 1.8 2004/08/24 06:42:51 starvik Exp $ + */ + +#include <linux/config.h> +#include <linux/version.h> +#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 <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_NAME "PCF8563" +#define DRIVER_VERSION "$Revision: 1.8 $" + +/* I2C bus slave registers. */ +#define RTC_I2C_READ 0xa3 +#define RTC_I2C_WRITE 0xa2 + +/* 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 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); + +static struct file_operations pcf8563_fops = { + .owner = THIS_MODULE, + .ioctl = pcf8563_ioctl, +}; + +unsigned char +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; + } + return res; +} + +void +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_hour = rtc_read(RTC_HOURS); + tm->tm_mday = rtc_read(RTC_DAY_OF_MONTH); + 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); + + 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; + + BCD_TO_BIN(tm->tm_sec); + BCD_TO_BIN(tm->tm_min); + BCD_TO_BIN(tm->tm_hour); + BCD_TO_BIN(tm->tm_mday); + BCD_TO_BIN(tm->tm_mon); + tm->tm_mon--; /* Month is 1..12 in RTC but 0..11 in linux */ +} + +int __init +pcf8563_init(void) +{ + unsigned char ret; + + i2c_init(); + + /* + * 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. + */ + 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; + + /* Clear the VL bit in the seconds register. */ + ret = rtc_read(RTC_SECONDS); + + if (rtc_write(RTC_SECONDS, (ret & 0x7f)) < 0) + goto err; + + /* Reset the alarms. */ + if (rtc_write(RTC_MINUTE_ALARM, 0x00) < 0) + goto err; + + if (rtc_write(RTC_HOUR_ALARM, 0x00) < 0) + goto err; + + if (rtc_write(RTC_DAY_ALARM, 0x00) < 0) + goto err; + + if (rtc_write(RTC_WEEKDAY_ALARM, 0x00) < 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; + +err: + printk(KERN_INFO "%s: Error initializing chip.\n", PCF8563_NAME); + return -1; +} + +void __exit +pcf8563_exit(void) +{ + if (unregister_chrdev(PCF8563_MAJOR, DEVICE_NAME) < 0) { + printk(KERN_INFO "%s: Unable to unregister device.\n", PCF8563_NAME); + } +} + +/* + * 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) +{ + /* 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; + + get_rtc_time(&tm); + + if (copy_to_user((struct rtc_time *) arg, &tm, sizeof(struct rtc_time))) { + return -EFAULT; + } + + 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; + + 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); + + 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_VLOW_SET: + { + /* Clear the VL bit in the seconds register */ + int ret = rtc_read(RTC_SECONDS); + + rtc_write(RTC_SECONDS, (ret & 0x7F)); + + return 0; + } + + default: + return -ENOTTY; + } + + return 0; +} + +static int __init +pcf8563_register(void) +{ + pcf8563_init(); + 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); + return 0; +} + +module_init(pcf8563_register); +module_exit(pcf8563_exit); |