/* x1205 - an 12c driver for the Xicor X1205 RTC Copyright 2004 Karen Spearel please send all reports to: kas11 at tampabay dot rr dot com based on linux/drivers/acron/char/pcf8583.h Copyright (C) 2000 Russell King This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* * i2c_adapter is the structure used to identify a physical i2c bus along * with the access algorithms necessary to access it. struct i2c_adapter { struct module *owner; unsigned int id; == is algo->id | hwdep.struct->id, for registered values see below unsigned int class; struct i2c_algorithm *algo; the algorithm to access the bus void *algo_data; --- administration stuff. int (*client_register)(struct i2c_client *); int (*client_unregister)(struct i2c_client *); data fields that are valid for all devices struct semaphore bus_lock; struct semaphore clist_lock; int timeout; int retries; struct device dev; the adapter device struct class_device class_dev; the class device #ifdef CONFIG_PROC_FS No need to set this when you initialize the adapter int inode; #endif def CONFIG_PROC_FS int nr; struct list_head clients; struct list_head list; char name[I2C_NAME_SIZE]; struct completion dev_released; struct completion class_dev_released; }; */ /*========== Driver for the X1205 on the Linksys NSLU2 ==================*/ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define RTC_GETDATETIME 0 #define RTC_SETTIME 1 #define RTC_SETDATETIME 2 #define I2C_M_WR 0 // just for consistancy // offsets into read buf - add 2 for write buf #define CCR_SEC 0 #define CCR_MIN 1 #define CCR_HOUR 2 #define CCR_MDAY 3 #define CCR_MONTH 4 #define CCR_YEAR 5 #define CCR_WDAY 6 #define CCR_Y2K 7 #define X1205_I2C_BUS_ADDR 0x6f // hardwired into x1205 #define X1205_ALM0_BASE 0x00 // Base address of the ALM0 #define X1205_CCR_BASE 0x30 // Base address of the CCR #define X1205_SR_ADDR 0x3f // Status Register #define X1205_SR_WEL 0x02 // Write Enable Latch bit #define X1205_SR_RWEL 0x04 // Register Write Enable Bit #define X1205_MILBIT 0x80 // this bit set in ccr.hour for 24 hr mode #define NOERR 0 #define RTC_NODATE 0 #define RTC_DATETOO 1 // comment out next line is your x1205 can't do page writes //#define X1205PAGEWRITE 1 #ifdef X1205PAGEWRITE #define DRIVERNAME "Xicor x1205 RTC Driver v0.9.3.3" #else #define DRIVERNAME "Xicor x1205 RTC Dvr v0.9.3.3NPW" #endif #define DEBUG KERN_DEBUG static int x1205_get_datetime(struct i2c_client *client, struct rtc_time *tm, u8 reg_base); static int x1205_set_datetime(struct i2c_client *client, struct rtc_time *tm, int datetoo, u8 reg_base); static int x1205_attach(struct i2c_adapter *adapter); static int x1205_detach(struct i2c_client *client); static int x1205_validate_tm(struct rtc_time *tm); static int x1205_command(struct i2c_client *client, unsigned int cmd, void *arg); static int x1205_sync_rtc(void); static int x1205_read(struct file *file, char *buf, size_t count, loff_t *ptr); static int x1205_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg); static int x1205_read_proc(char *buf, char **start, off_t off, int len, int *eof, void *data); static struct i2c_driver x1205_driver = { .owner = THIS_MODULE, .name = DRIVERNAME, .id = I2C_DRIVERID_X1205, .flags = I2C_DF_NOTIFY, .attach_adapter = &x1205_attach, //we don't need to probe...x1205 is hardwired @ 0x6f .detach_client = &x1205_detach, .command = &x1205_command, //this prolly never gets called...used internally tho }; static struct i2c_client x1205_i2c_client = { .id = I2C_DRIVERID_X1205, .flags = 0, .addr = X1205_I2C_BUS_ADDR, // chip address - NOTE: 7bit .adapter = NULL, // the adapter we sit on assigned in attach .driver = &x1205_driver, // and our access routines .usage_count = 0, // How many accesses currently to this client .dev = {}, // the device structure .list = {}, .name = DRIVERNAME, .released = {}, }; static struct file_operations rtc_fops = { owner: THIS_MODULE, ioctl: x1205_ioctl, read: x1205_read, }; static struct miscdevice x1205_miscdev = { .minor = RTC_MINOR, .name = "rtc", .fops = &rtc_fops, }; extern int (*set_rtc)(void); static unsigned epoch = 1900; //coresponds to year 0 static unsigned rtc_epoch = 2000; static const unsigned char days_in_mo[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; //===================================CODE====================================== // in the routines that deal directly with the x1205 hardware, we use // rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch // Epoch is inited as 2000. Time is set to UT //============================================================================= static int x1205_get_datetime(struct i2c_client *client, struct rtc_time *tm, u8 reg_base) { static unsigned char addr[2] = { 0,} ; unsigned char buf[8]; struct i2c_msg msgs[2] = { { client->addr, I2C_M_WR, 2, addr }, //msg 1 = send base address { client->addr, I2C_M_RD, 8, buf }, //msg 2 = read sequential data }; addr[1] = reg_base; if ((i2c_transfer(client->adapter, msgs, 2)) == 2) { //did we read 2 messages? printk(KERN_DEBUG "raw x1205 read data - sec-%02x min-%02x hr-%02x mday-%02x mon-%02x year-%02x wday-%02x y2k-%02x\n", buf[0],buf[1],buf[2],buf[3],buf[4],buf[5],buf[6], buf[7]); tm->tm_sec = BCD2BIN(buf[CCR_SEC]); tm->tm_min = BCD2BIN(buf[CCR_MIN]); buf[CCR_HOUR] &= ~X1205_MILBIT; tm->tm_hour = BCD2BIN(buf[CCR_HOUR]); //hr is 0-23 tm->tm_mday = BCD2BIN(buf[CCR_MDAY]); tm->tm_mon = BCD2BIN(buf[CCR_MONTH]); rtc_epoch = BCD2BIN(buf[CCR_Y2K]) * 100; tm->tm_year = BCD2BIN(buf[CCR_YEAR]) + rtc_epoch - epoch; tm->tm_wday = buf[CCR_WDAY]; printk(KERN_DEBUG "rtc_time output data - sec-%02d min-%02d hr-%02d mday-%02d mon-%02d year-%02d wday-%02d epoch-%d rtc_epoch-%d\n", tm->tm_sec,tm->tm_min,tm->tm_hour,tm->tm_mday,tm->tm_mon,tm->tm_year,tm->tm_wday,epoch, rtc_epoch); } else { printk(KERN_DEBUG "i2c_transfer Read Error\n"); return -EIO; } return NOERR; } // x1205pagewrite allows writing a block of registers in msg3 even though the x1205 says // nothing about this in its spec. // it needs more testing as it is possible some x1205s are actually not-completely- // functional x1226s and there is a reason for the multiple write to not be in the spec. // anyhow, it is enabled for the time being...and we even push out luck by sending 10 bytes static int x1205_set_datetime(struct i2c_client *client, struct rtc_time *tm, int datetoo, u8 reg_base) { static unsigned char wel[3] = { 0, X1205_SR_ADDR, X1205_SR_WEL }; static unsigned char rwel[3] = { 0, X1205_SR_ADDR, X1205_SR_WEL | X1205_SR_RWEL }; static unsigned char diswe[3] = { 0, X1205_SR_ADDR, 0 }; #ifdef X1205PAGEWRITE static unsigned char buf[10] = { 0, X1205_CCR_BASE, }; struct i2c_msg msgs[4] = { { client->addr, I2C_M_WR, 3, wel }, //msg 1 = write WEL to to ccr sr { client->addr, I2C_M_WR, 3, rwel }, //msg 2 = write RWEL to ccr sr { client->addr, I2C_M_WR, 10, buf }, //msg 3 = write ccr base addr +seq data { client->addr, I2C_M_WR, 3, diswe }, //msg 4 = 0 to ccr sr to disable writes }; msgs[2].len = 5; // 5 bytes + addr to set time only buf [1] = reg_base; buf[CCR_SEC+2] = BIN2BCD(tm->tm_sec); buf[CCR_MIN+2] = BIN2BCD(tm->tm_min); buf[CCR_HOUR+2] = BIN2BCD(tm->tm_hour) | X1205_MILBIT; // set 24 hour format if (datetoo == 1) { buf[CCR_MDAY+2] = BIN2BCD(tm->tm_mday); buf[CCR_MONTH+2] = BIN2BCD(tm->tm_mon); // input is 0-11 buf[CCR_YEAR+2] = BIN2BCD((tm->tm_year + epoch - rtc_epoch)); // input is yrs since 1900 buf[CCR_WDAY+2] = tm->tm_wday & 7; buf[CCR_Y2K+2] = BIN2BCD((rtc_epoch/100)); msgs[2].len += 5; //5 more bytes to set date } printk(KERN_DEBUG "rtc_time input - sec-%02d min-%02d hour-%02d mday-%02d mon-%02d year-%02d wday-%02d epoch-%d rtc_epoch-%d\n", tm->tm_sec,tm->tm_min,tm->tm_hour,tm->tm_mday,tm->tm_mon,tm->tm_year,tm->tm_wday, epoch, rtc_epoch); printk(KERN_DEBUG "BCD write data - sec-%02x min-%02x hour-%02x mday-%02x mon-%02x year-%02x wday-%02x y2k-%02x\n", buf[2],buf[3],buf[4],buf[5],buf[6], buf[7], buf[8], buf[9]); if ((i2c_transfer(client->adapter, msgs, 4)) != 4) return -EIO; return NOERR; #else //do this if page writes aren't working int i,xfer; static unsigned char data[3] = { 0,}; static unsigned char buf[8]; buf[CCR_SEC] = BIN2BCD(tm->tm_sec); buf[CCR_MIN] = BIN2BCD(tm->tm_min); buf[CCR_HOUR] = BIN2BCD(tm->tm_hour) | X1205_MILBIT; // set 24 hour format if (datetoo == 1) { buf[CCR_MDAY] = BIN2BCD(tm->tm_mday); buf[CCR_MONTH] = BIN2BCD(tm->tm_mon); // input is 0-11 buf[CCR_YEAR] = BIN2BCD((tm->tm_year + epoch - rtc_epoch)); // input is yrs since 1900 buf[CCR_WDAY] = tm->tm_wday & 7; buf[CCR_Y2K] = BIN2BCD((rtc_epoch/100)); } printk(KERN_DEBUG "rtc_time input - sec-%02d min-%02d hour-%02d mday-%02d mon-%02d year-%02d wday-%02d epoch-%d rtc_epoch-%d\n", tm->tm_sec,tm->tm_min,tm->tm_hour,tm->tm_mday,tm->tm_mon,tm->tm_year,tm->tm_wday, epoch, rtc_epoch); xfer = i2c_master_send(client, wel, 3); printk(KERN_DEBUG "wen - %x\n", xfer); if (xfer != 3) return -EIO; xfer = i2c_master_send(client, rwel, 3); printk(KERN_DEBUG "wenb - %x\n", xfer); if (xfer != 3) return -EIO; for (i = 0; i < 8; i++) { data[1] = i + reg_base; data[2] = buf[i]; xfer = i2c_master_send(client, data, 3); printk(KERN_DEBUG "xfer - %d addr - %02x data - %02x\n", xfer, data[1], data[2]); if (xfer != 3) return -EIO; }; xfer = i2c_master_send(client, diswe, 3); printk(KERN_DEBUG "wdis - %x\n", xfer); if (xfer != 3) return -EIO; return NOERR; #endif } //============================================================================= static int x1205_attach(struct i2c_adapter *adapter) { struct rtc_time tm; struct timespec tv; int errno; x1205_i2c_client.adapter = adapter; x1205_i2c_client.id++; if ((x1205_get_datetime(&x1205_i2c_client, &tm, X1205_CCR_BASE)) != NOERR) //test for functional driver return -EIO; if ((errno = i2c_attach_client(&x1205_i2c_client)) != NOERR) return errno; tv.tv_nsec = tm.tm_sec * 10000000; tv.tv_sec = mktime(tm.tm_year+epoch, tm.tm_mon+1, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec); do_settimeofday(&tv); set_rtc = x1205_sync_rtc; printk(KERN_DEBUG "%s attached on adapter %s\n",x1205_i2c_client.name, x1205_i2c_client.adapter->name); //why is this name a null string? return NOERR; } static int x1205_detach(struct i2c_client *client) { int errno; if ((errno = i2c_detach_client(client)) != 0) { printk(KERN_DEBUG "i2c_detach failed - errno = %d\n", errno); return errno; } return NOERR; } // make sure the rtc_time values are in bounds static int x1205_validate_tm(struct rtc_time *tm) { tm->tm_year += 1900; if (tm->tm_year < 1970) return -EINVAL; if ((tm->tm_mon > 11) || (tm->tm_mday == 0)) return -EINVAL; if (tm->tm_mday > (days_in_mo[tm->tm_mon] + ( (tm->tm_mon == 1) && ((!(tm->tm_year % 4) && (tm->tm_year % 100) ) || !(tm->tm_year % 400))))) return -EINVAL; if ((tm->tm_year -= epoch) > 255) return -EINVAL; if ((tm->tm_hour >= 24) || (tm->tm_min >= 60) || (tm->tm_sec >= 60)) return -EINVAL; return NOERR; } static int x1205_command(struct i2c_client *client, unsigned int cmd, void *tm) { int errno, dodate = RTC_DATETOO; if (client == NULL || tm == NULL) return -EINVAL; if (!capable(CAP_SYS_TIME)) return -EACCES; printk(KERN_DEBUG "x1205_command %d\n", cmd); switch (cmd) { case RTC_GETDATETIME: return x1205_get_datetime(client, tm, X1205_CCR_BASE); case RTC_SETTIME: // note fall thru dodate = RTC_NODATE; case RTC_SETDATETIME: if ((errno = x1205_validate_tm(tm)) < NOERR) return errno; return x1205_set_datetime(client, tm, dodate, X1205_CCR_BASE); default: return -EINVAL; } } static int x1205_sync_rtc(void) { struct rtc_time new_tm, old_tm; unsigned long cur_secs = xtime.tv_sec; printk(KERN_DEBUG "x1205_sync_rtc entry\n"); if (x1205_command(&x1205_i2c_client, RTC_GETDATETIME, &old_tm)) return 0; // xtime.tv_nsec = old_tm.tm_sec * 10000000; //FIXME: new_tm.tm_sec = cur_secs % 60; cur_secs /= 60; new_tm.tm_min = cur_secs % 60; cur_secs /= 60; new_tm.tm_hour = cur_secs % 24; /* * avoid writing when we're going to change the day * of the month. We will retry in the next minute. * This basically means that if the RTC must not drift * by more than 1 minute in 11 minutes. */ if ((old_tm.tm_hour == 23 && old_tm.tm_min == 59) || (new_tm.tm_hour == 23 && new_tm.tm_min == 59)) return 1; printk(KERN_DEBUG "x1205_sync_rtc exit\n"); return x1205_command(&x1205_i2c_client, RTC_SETTIME, &new_tm); } static int x1205_read(struct file *file, char *buf, size_t count, loff_t *ptr) { struct rtc_time tm; if ((x1205_get_datetime(&x1205_i2c_client, &tm, X1205_CCR_BASE)) < NOERR) return -EIO; return copy_to_user(buf, &tm, sizeof(tm)) ? -EFAULT : NOERR; } //============================================================================== static int x1205_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) { struct rtc_time tm; int errno; printk(KERN_DEBUG "ioctl = %x\n", cmd); switch (cmd) { case RTC_RD_TIME: if ((x1205_get_datetime(&x1205_i2c_client, &tm, X1205_CCR_BASE)) < NOERR) return -EIO; break; case RTC_SET_TIME: if (!capable(CAP_SYS_TIME)) return -EACCES; if (copy_from_user(&tm, (struct rtc_time *) arg, sizeof(struct rtc_time))) return -EFAULT; if ((errno = x1205_validate_tm(&tm)) < NOERR) return errno; return x1205_set_datetime(&x1205_i2c_client, &tm, RTC_DATETOO, X1205_CCR_BASE); case RTC_ALM_SET: //FIXME: set Control Regs if (copy_from_user(&tm, (struct rtc_time *) arg, sizeof(struct rtc_time))) return -EFAULT; return x1205_set_datetime(&x1205_i2c_client, &tm, RTC_DATETOO, X1205_ALM0_BASE); case RTC_ALM_READ: if ((x1205_get_datetime(&x1205_i2c_client, &tm, X1205_ALM0_BASE)) < NOERR) return -EIO; break; case RTC_EPOCH_READ: return put_user (epoch, (unsigned long __user *)arg); case RTC_EPOCH_SET: if (arg < 1900) return -EINVAL; if (!capable(CAP_SYS_TIME)) return -EACCES; epoch = arg; return 0; default: return -ENOTTY; } return copy_to_user((void __user *)arg, &tm, sizeof tm) ? -EFAULT : 0; } static int x1205_read_proc(char *buf, char **start, off_t off, int len, int *eof, void *data) { struct rtc_time tm; int slen, errno; if ((errno = x1205_get_datetime(&x1205_i2c_client, &tm, X1205_CCR_BASE)) < NOERR) return errno; // here we return the real year and the month as 1-12 since it is human-readable slen = sprintf(buf, "rtc_time\t: %02d:%02d:%02d\nrtc_date\t: %04d-%02d-%02d\n", tm.tm_hour, tm.tm_min, tm.tm_sec, tm.tm_year + 1900, tm.tm_mon+1, tm.tm_mday); printk(KERN_DEBUG "raw rtc_time\t: %02d:%02d:%02d\nraw rtc_date\t: %04d-%02d-%02d\n", tm.tm_hour, tm.tm_min, tm.tm_sec, tm.tm_year, tm.tm_mon, tm.tm_mday); if (slen <= off + len) *eof = 1; *start = buf + off; slen -= off; if (slen > len) slen = len; if ( slen < 0 ) slen = 0; return slen; } static int __init x1205_init(void) { struct rtc_time tm; int errno; printk(KERN_INFO "LOADED %s\n", DRIVERNAME); if ((errno = i2c_add_driver(&x1205_driver)) != NOERR) { dev_dbg(x1205_i2c_client.dev, "x1205_init failed - errno = %d\n", errno); return (errno); } if ((errno = misc_register(&x1205_miscdev)) != NOERR) { dev_dbg(x1205_i2c_client.dev, "Register Misc Driver failed - errno = %d\n", errno); i2c_del_driver(&x1205_driver); return errno; } if (create_proc_read_entry("driver/rtc", 0, NULL, x1205_read_proc, NULL) < NOERR) return -ENOMEM; if ((x1205_get_datetime(&x1205_i2c_client, &tm, X1205_CCR_BASE)) != NOERR) //test for functionality return -EIO; return NOERR; } static void __exit x1205_exit(void) { remove_proc_entry("driver/rtc", NULL); misc_deregister(&x1205_miscdev); i2c_del_driver(&x1205_driver); set_rtc = NULL; } MODULE_AUTHOR("Karen Spearel "); MODULE_DESCRIPTION("Xicor X1205-RTC Driver"); MODULE_LICENSE("GPL"); static int debug = 7; module_param(debug, bool, 0644); MODULE_PARM_DESC(debug, "Debugging enabled = 1"); module_init(x1205_init); module_exit(x1205_exit);