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authorSrikant Patnaik2015-01-11 12:28:04 +0530
committerSrikant Patnaik2015-01-11 12:28:04 +0530
commit871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch)
tree8718f573808810c2a1e8cb8fb6ac469093ca2784 /arch/cris/arch-v10/drivers/pcf8563.c
parent9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff)
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Moved, renamed, and deleted files
The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure.
Diffstat (limited to 'arch/cris/arch-v10/drivers/pcf8563.c')
-rw-r--r--arch/cris/arch-v10/drivers/pcf8563.c380
1 files changed, 380 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 00000000..9da05686
--- /dev/null
+++ b/arch/cris/arch-v10/drivers/pcf8563.c
@@ -0,0 +1,380 @@
+/*
+ * 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/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: 1.24 $"
+
+/* 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 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 *, 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,
+ .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);
+ ret = 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 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);
+
+ /* 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);