Added missing tegra files.HEADmaster

2 files changed, 897 insertions, 0 deletions

diff --git a/arch/cris/arch-v10/drivers/ds1302.c b/arch/cris/arch-v10/drivers/ds1302.c
new file mode 100644
index 00000000000..3d655dcc65d
--- /dev/null
+++ b/arch/cris/arch-v10/drivers/ds1302.c
@@ -0,0 +1,516 @@
+/*!***************************************************************************
+*!
+*! FILE NAME  : ds1302.c
+*!
+*! DESCRIPTION: Implements an interface for the DS1302 RTC through Etrax I/O
+*!
+*! Functions exported: ds1302_readreg, ds1302_writereg, ds1302_init
+*!
+*! ---------------------------------------------------------------------------
+*!
+*! (C) Copyright 1999-2007 Axis Communications AB, LUND, SWEDEN
+*!
+*!***************************************************************************/
+
+
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/miscdevice.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/bcd.h>
+#include <linux/capability.h>
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <arch/svinto.h>
+#include <asm/io.h>
+#include <asm/rtc.h>
+#include <arch/io_interface_mux.h>
+
+#include "i2c.h"
+
+#define RTC_MAJOR_NR 121 /* local major, change later */
+
+static DEFINE_MUTEX(ds1302_mutex);
+static const char ds1302_name[] = "ds1302";
+
+/* The DS1302 might be connected to different bits on different products. 
+ * It has three signals - SDA, SCL and RST. RST and SCL are always outputs,
+ * but SDA can have a selected direction.
+ * For now, only PORT_PB is hardcoded.
+ */
+
+/* The RST bit may be on either the Generic Port or Port PB. */
+#ifdef CONFIG_ETRAX_DS1302_RST_ON_GENERIC_PORT
+#define TK_RST_OUT(x) REG_SHADOW_SET(R_PORT_G_DATA,  port_g_data_shadow,  CONFIG_ETRAX_DS1302_RSTBIT, x)
+#define TK_RST_DIR(x)
+#else
+#define TK_RST_OUT(x) REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, CONFIG_ETRAX_DS1302_RSTBIT, x)
+#define TK_RST_DIR(x) REG_SHADOW_SET(R_PORT_PB_DIR,  port_pb_dir_shadow,  CONFIG_ETRAX_DS1302_RSTBIT, x)
+#endif
+
+
+#define TK_SDA_OUT(x) REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, CONFIG_ETRAX_DS1302_SDABIT, x)
+#define TK_SCL_OUT(x) REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, CONFIG_ETRAX_DS1302_SCLBIT, x)
+
+#define TK_SDA_IN()   ((*R_PORT_PB_READ >> CONFIG_ETRAX_DS1302_SDABIT) & 1)
+/* 1 is out, 0 is in */
+#define TK_SDA_DIR(x) REG_SHADOW_SET(R_PORT_PB_DIR,  port_pb_dir_shadow,  CONFIG_ETRAX_DS1302_SDABIT, x)
+#define TK_SCL_DIR(x) REG_SHADOW_SET(R_PORT_PB_DIR,  port_pb_dir_shadow,  CONFIG_ETRAX_DS1302_SCLBIT, x)
+
+
+/*
+ * The reason for tempudelay and not udelay is that loops_per_usec
+ * (used in udelay) is not set when functions here are called from time.c 
+ */
+
+static void tempudelay(int usecs) 
+{
+        volatile int loops;
+
+        for(loops = usecs * 12; loops > 0; loops--)
+                /* nothing */;  
+}
+
+
+/* Send 8 bits. */
+static void
+out_byte(unsigned char x) 
+{
+        int i;
+        TK_SDA_DIR(1);
+        for (i = 8; i--;) {
+                /* The chip latches incoming bits on the rising edge of SCL. */
+                TK_SCL_OUT(0);
+                TK_SDA_OUT(x & 1);
+                tempudelay(1);
+                TK_SCL_OUT(1);
+                tempudelay(1);
+                x >>= 1;
+        }
+        TK_SDA_DIR(0);
+}
+
+static unsigned char
+in_byte(void) 
+{
+        unsigned char x = 0;
+        int i;
+
+        /* Read byte. Bits come LSB first, on the falling edge of SCL.
+         * Assume SDA is in input direction already.
+         */
+        TK_SDA_DIR(0);
+
+        for (i = 8; i--;) {
+                TK_SCL_OUT(0);
+                tempudelay(1);
+                x >>= 1;
+                x |= (TK_SDA_IN() << 7);
+                TK_SCL_OUT(1);
+                tempudelay(1);
+        }
+
+        return x;
+}
+
+/* Prepares for a transaction by de-activating RST (active-low). */
+
+static void
+start(void) 
+{
+        TK_SCL_OUT(0);
+        tempudelay(1);
+        TK_RST_OUT(0);
+        tempudelay(5);
+        TK_RST_OUT(1);  
+}
+
+/* Ends a transaction by taking RST active again. */
+
+static void
+stop(void) 
+{
+        tempudelay(2);
+        TK_RST_OUT(0);
+}
+
+/* Enable writing. */
+
+static void
+ds1302_wenable(void) 
+{
+        start();        
+        out_byte(0x8e); /* Write control register  */
+        out_byte(0x00); /* Disable write protect bit 7 = 0 */
+        stop();
+}
+
+/* Disable writing. */
+
+static void
+ds1302_wdisable(void) 
+{
+        start();
+        out_byte(0x8e); /* Write control register  */
+        out_byte(0x80); /* Disable write protect bit 7 = 0 */
+        stop();
+}
+
+
+
+/* Read a byte from the selected register in the DS1302. */
+
+unsigned char
+ds1302_readreg(int reg) 
+{
+        unsigned char x;
+
+        start();
+        out_byte(0x81 | (reg << 1)); /* read register */
+        x = in_byte();
+        stop();
+
+        return x;
+}
+
+/* Write a byte to the selected register. */
+
+void
+ds1302_writereg(int reg, unsigned char val) 
+{
+#ifndef CONFIG_ETRAX_RTC_READONLY
+        int do_writereg = 1;
+#else
+        int do_writereg = 0;
+
+        if (reg == RTC_TRICKLECHARGER)
+                do_writereg = 1;
+#endif
+
+        if (do_writereg) {
+                ds1302_wenable();
+                start();
+                out_byte(0x80 | (reg << 1)); /* write register */
+                out_byte(val);
+                stop();
+                ds1302_wdisable();
+        }
+}
+
+void
+get_rtc_time(struct rtc_time *rtc_tm) 
+{
+        unsigned long flags;
+
+        local_irq_save(flags);
+
+        rtc_tm->tm_sec = CMOS_READ(RTC_SECONDS);
+        rtc_tm->tm_min = CMOS_READ(RTC_MINUTES);
+        rtc_tm->tm_hour = CMOS_READ(RTC_HOURS);
+        rtc_tm->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH);
+        rtc_tm->tm_mon = CMOS_READ(RTC_MONTH);
+        rtc_tm->tm_year = CMOS_READ(RTC_YEAR);
+
+        local_irq_restore(flags);
+        
+        rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
+        rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
+        rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
+        rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
+        rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
+        rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
+
+        /*
+         * Account for differences between how the RTC uses the values
+         * and how they are defined in a struct rtc_time;
+         */
+
+        if (rtc_tm->tm_year <= 69)
+                rtc_tm->tm_year += 100;
+
+        rtc_tm->tm_mon--;
+}
+
+static unsigned char days_in_mo[] = 
+    {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
+
+/* ioctl that supports RTC_RD_TIME and RTC_SET_TIME (read and set time/date). */
+
+static int rtc_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+        unsigned long flags;
+
+        switch(cmd) {
+                case RTC_RD_TIME:       /* read the time/date from RTC  */
+                {
+                        struct rtc_time rtc_tm;
+                                                
+                        memset(&rtc_tm, 0, sizeof (struct rtc_time));
+                        get_rtc_time(&rtc_tm);                                          
+                        if (copy_to_user((struct rtc_time*)arg, &rtc_tm, sizeof(struct rtc_time)))
+                                return -EFAULT; 
+                        return 0;
+                }
+
+                case RTC_SET_TIME:      /* set the RTC */
+                {
+                        struct rtc_time rtc_tm;
+                        unsigned char mon, day, hrs, min, sec, leap_yr;
+                        unsigned int yrs;
+
+                        if (!capable(CAP_SYS_TIME))
+                                return -EPERM;
+
+                        if (copy_from_user(&rtc_tm, (struct rtc_time*)arg, sizeof(struct rtc_time)))
+                                return -EFAULT;
+
+                        yrs = rtc_tm.tm_year + 1900;
+                        mon = rtc_tm.tm_mon + 1;   /* tm_mon starts at zero */
+                        day = rtc_tm.tm_mday;
+                        hrs = rtc_tm.tm_hour;
+                        min = rtc_tm.tm_min;
+                        sec = rtc_tm.tm_sec;
+                        
+                        
+                        if ((yrs < 1970) || (yrs > 2069))
+                                return -EINVAL;
+
+                        leap_yr = ((!(yrs % 4) && (yrs % 100)) || !(yrs % 400));
+
+                        if ((mon > 12) || (day == 0))
+                                return -EINVAL;
+
+                        if (day > (days_in_mo[mon] + ((mon == 2) && leap_yr)))
+                                return -EINVAL;
+                        
+                        if ((hrs >= 24) || (min >= 60) || (sec >= 60))
+                                return -EINVAL;
+
+                        if (yrs >= 2000)
+                                yrs -= 2000;    /* RTC (0, 1, ... 69) */
+                        else
+                                yrs -= 1900;    /* RTC (70, 71, ... 99) */
+
+                        sec = bin2bcd(sec);
+                        min = bin2bcd(min);
+                        hrs = bin2bcd(hrs);
+                        day = bin2bcd(day);
+                        mon = bin2bcd(mon);
+                        yrs = bin2bcd(yrs);
+
+                        local_irq_save(flags);
+                        CMOS_WRITE(yrs, RTC_YEAR);
+                        CMOS_WRITE(mon, RTC_MONTH);
+                        CMOS_WRITE(day, RTC_DAY_OF_MONTH);
+                        CMOS_WRITE(hrs, RTC_HOURS);
+                        CMOS_WRITE(min, RTC_MINUTES);
+                        CMOS_WRITE(sec, RTC_SECONDS);
+                        local_irq_restore(flags);
+
+                        /* Notice that at this point, the RTC is updated but
+                         * the kernel is still running with the old time.
+                         * You need to set that separately with settimeofday
+                         * or adjtimex.
+                         */
+                        return 0;
+                }
+
+                case RTC_SET_CHARGE: /* set the RTC TRICKLE CHARGE register */
+                {
+                        int tcs_val;
+
+                        if (!capable(CAP_SYS_TIME))
+                                return -EPERM;
+                        
+                        if(copy_from_user(&tcs_val, (int*)arg, sizeof(int)))
+                                return -EFAULT;
+
+                        tcs_val = RTC_TCR_PATTERN | (tcs_val & 0x0F);
+                        ds1302_writereg(RTC_TRICKLECHARGER, tcs_val);
+                        return 0;
+                }
+                case RTC_VL_READ:
+                {
+                        /* TODO:
+                         * Implement voltage low detection support
+                         */
+                        printk(KERN_WARNING "DS1302: RTC Voltage Low detection"
+                               " is not supported\n");
+                        return 0;
+                }
+                case RTC_VL_CLR:
+                {
+                        /* TODO:
+                         * Nothing to do since Voltage Low detection is not supported
+                         */
+                        return 0;
+                }
+                default:
+                        return -ENOIOCTLCMD;
+        }
+}
+
+static long rtc_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+        int ret;
+
+        mutex_lock(&ds1302_mutex);
+        ret = rtc_ioctl(file, cmd, arg);
+        mutex_unlock(&ds1302_mutex);
+
+        return ret;
+}
+
+static void
+print_rtc_status(void)
+{
+        struct rtc_time tm;
+
+        get_rtc_time(&tm);
+
+        /*
+         * There is no way to tell if the luser has the RTC set for local
+         * time or for Universal Standard Time (GMT). Probably local though.
+         */
+
+        printk(KERN_INFO "rtc_time\t: %02d:%02d:%02d\n",
+               tm.tm_hour, tm.tm_min, tm.tm_sec);
+        printk(KERN_INFO "rtc_date\t: %04d-%02d-%02d\n",
+               tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);
+}
+
+/* The various file operations we support. */
+
+static const struct file_operations rtc_fops = {
+        .owner          = THIS_MODULE,
+        .unlocked_ioctl = rtc_unlocked_ioctl,
+        .llseek         = noop_llseek,
+}; 
+
+/* Probe for the chip by writing something to its RAM and try reading it back. */
+
+#define MAGIC_PATTERN 0x42
+
+static int __init
+ds1302_probe(void) 
+{
+        int retval, res; 
+
+        TK_RST_DIR(1);
+        TK_SCL_DIR(1);
+        TK_SDA_DIR(0);
+        
+        /* Try to talk to timekeeper. */
+
+        ds1302_wenable();  
+        start();
+        out_byte(0xc0); /* write RAM byte 0 */  
+        out_byte(MAGIC_PATTERN); /* write something magic */
+        start();
+        out_byte(0xc1); /* read RAM byte 0 */
+
+        if((res = in_byte()) == MAGIC_PATTERN) {
+                stop();
+                ds1302_wdisable();
+                printk(KERN_INFO "%s: RTC found.\n", ds1302_name);
+                printk(KERN_INFO "%s: SDA, SCL, RST on PB%i, PB%i, %s%i\n",
+                       ds1302_name,
+                       CONFIG_ETRAX_DS1302_SDABIT,
+                       CONFIG_ETRAX_DS1302_SCLBIT,
+#ifdef CONFIG_ETRAX_DS1302_RST_ON_GENERIC_PORT
+                       "GENIO",
+#else
+                       "PB",
+#endif
+                       CONFIG_ETRAX_DS1302_RSTBIT);
+                       print_rtc_status();
+                retval = 1;
+        } else {
+                stop();
+                retval = 0;
+        }
+
+        return retval;
+}
+
+
+/* Just probe for the RTC and register the device to handle the ioctl needed. */
+
+int __init
+ds1302_init(void) 
+{
+#ifdef CONFIG_ETRAX_I2C
+        i2c_init();
+#endif
+
+        if (!ds1302_probe()) {
+#ifdef CONFIG_ETRAX_DS1302_RST_ON_GENERIC_PORT
+#if CONFIG_ETRAX_DS1302_RSTBIT == 27
+                /*
+                 * The only way to set g27 to output is to enable ATA.
+                 *
+                 * Make sure that R_GEN_CONFIG is setup correct.
+                 */
+                /* Allocating the ATA interface will grab almost all
+                 * pins in I/O groups a, b, c and d.  A consequence of
+                 * allocating the ATA interface is that the fixed
+                 * interfaces shared RAM, parallel port 0, parallel
+                 * port 1, parallel port W, SCSI-8 port 0, SCSI-8 port
+                 * 1, SCSI-W, serial port 2, serial port 3,
+                 * synchronous serial port 3 and USB port 2 and almost
+                 * all GPIO pins on port g cannot be used.
+                 */
+                if (cris_request_io_interface(if_ata, "ds1302/ATA")) {
+                        printk(KERN_WARNING "ds1302: Failed to get IO interface\n");
+                        return -1;
+                }
+
+#elif CONFIG_ETRAX_DS1302_RSTBIT == 0
+                if (cris_io_interface_allocate_pins(if_gpio_grp_a,
+                                                    'g',
+                                                    CONFIG_ETRAX_DS1302_RSTBIT,
+                                                    CONFIG_ETRAX_DS1302_RSTBIT)) {
+                        printk(KERN_WARNING "ds1302: Failed to get IO interface\n");
+                        return -1;
+                }
+
+                /* Set the direction of this bit to out. */
+                genconfig_shadow = ((genconfig_shadow &
+                                     ~IO_MASK(R_GEN_CONFIG, g0dir)) |
+                                   (IO_STATE(R_GEN_CONFIG, g0dir, out)));
+                *R_GEN_CONFIG = genconfig_shadow;
+#endif
+                if (!ds1302_probe()) {
+                        printk(KERN_WARNING "%s: RTC not found.\n", ds1302_name);
+                        return -1;
+                }
+#else
+                printk(KERN_WARNING "%s: RTC not found.\n", ds1302_name);
+                return -1;
+#endif
+        }
+        /* Initialise trickle charger */
+        ds1302_writereg(RTC_TRICKLECHARGER,
+                        RTC_TCR_PATTERN |(CONFIG_ETRAX_DS1302_TRICKLE_CHARGE & 0x0F));
+        /* Start clock by resetting CLOCK_HALT */
+        ds1302_writereg(RTC_SECONDS, (ds1302_readreg(RTC_SECONDS) & 0x7F));
+        return 0;
+}
+
+static int __init ds1302_register(void)
+{
+        ds1302_init();
+        if (register_chrdev(RTC_MAJOR_NR, ds1302_name, &rtc_fops)) {
+                printk(KERN_INFO "%s: unable to get major %d for rtc\n", 
+                       ds1302_name, RTC_MAJOR_NR);
+                return -1;
+        }
+        return 0;
+
+}
+
+module_init(ds1302_register);
diff --git a/arch/cris/arch-v10/drivers/pcf8563.c b/arch/cris/arch-v10/drivers/pcf8563.c
new file mode 100644
index 00000000000..1391b731ad1
--- /dev/null
+++ b/arch/cris/arch-v10/drivers/pcf8563.c
@@ -0,0 +1,381 @@
+/*
+ * 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: 1.24 $"
+
+/* 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);