/* * Driver for Epson's RTC module RX-8025 SA/NB * * Copyright (C) 2009 Wolfgang Grandegger <wg@grandegger.com> * * Copyright (C) 2005 by Digi International Inc. * All rights reserved. * * Modified by fengjh at rising.com.cn * <http://lists.lm-sensors.org/mailman/listinfo/lm-sensors> * 2006.11 * * Code cleanup by Sergei Poselenov, <sposelenov@emcraft.com> * Converted to new style by Wolfgang Grandegger <wg@grandegger.com> * Alarm and periodic interrupt added by Dmitry Rakhchev <rda@emcraft.com> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * version 2 as published by the Free Software Foundation. */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/slab.h> #include <linux/init.h> #include <linux/bcd.h> #include <linux/i2c.h> #include <linux/list.h> #include <linux/rtc.h> /* Register definitions */ #define RX8025_REG_SEC 0x00 #define RX8025_REG_MIN 0x01 #define RX8025_REG_HOUR 0x02 #define RX8025_REG_WDAY 0x03 #define RX8025_REG_MDAY 0x04 #define RX8025_REG_MONTH 0x05 #define RX8025_REG_YEAR 0x06 #define RX8025_REG_DIGOFF 0x07 #define RX8025_REG_ALWMIN 0x08 #define RX8025_REG_ALWHOUR 0x09 #define RX8025_REG_ALWWDAY 0x0a #define RX8025_REG_ALDMIN 0x0b #define RX8025_REG_ALDHOUR 0x0c /* 0x0d is reserved */ #define RX8025_REG_CTRL1 0x0e #define RX8025_REG_CTRL2 0x0f #define RX8025_BIT_CTRL1_CT (7 << 0) /* 1 Hz periodic level irq */ #define RX8025_BIT_CTRL1_CT_1HZ 4 #define RX8025_BIT_CTRL1_TEST (1 << 3) #define RX8025_BIT_CTRL1_1224 (1 << 5) #define RX8025_BIT_CTRL1_DALE (1 << 6) #define RX8025_BIT_CTRL1_WALE (1 << 7) #define RX8025_BIT_CTRL2_DAFG (1 << 0) #define RX8025_BIT_CTRL2_WAFG (1 << 1) #define RX8025_BIT_CTRL2_CTFG (1 << 2) #define RX8025_BIT_CTRL2_PON (1 << 4) #define RX8025_BIT_CTRL2_XST (1 << 5) #define RX8025_BIT_CTRL2_VDET (1 << 6) /* Clock precision adjustment */ #define RX8025_ADJ_RESOLUTION 3050 /* in ppb */ #define RX8025_ADJ_DATA_MAX 62 #define RX8025_ADJ_DATA_MIN -62 static const struct i2c_device_id rx8025_id[] = { { "rx8025", 0 }, { } }; MODULE_DEVICE_TABLE(i2c, rx8025_id); struct rx8025_data { struct i2c_client *client; struct rtc_device *rtc; struct work_struct work; u8 ctrl1; unsigned exiting:1; }; static int rx8025_read_reg(struct i2c_client *client, int number, u8 *value) { int ret = i2c_smbus_read_byte_data(client, (number << 4) | 0x08); if (ret < 0) { dev_err(&client->dev, "Unable to read register #%d\n", number); return ret; } *value = ret; return 0; } static int rx8025_read_regs(struct i2c_client *client, int number, u8 length, u8 *values) { int ret = i2c_smbus_read_i2c_block_data(client, (number << 4) | 0x08, length, values); if (ret != length) { dev_err(&client->dev, "Unable to read registers #%d..#%d\n", number, number + length - 1); return ret < 0 ? ret : -EIO; } return 0; } static int rx8025_write_reg(struct i2c_client *client, int number, u8 value) { int ret = i2c_smbus_write_byte_data(client, number << 4, value); if (ret) dev_err(&client->dev, "Unable to write register #%d\n", number); return ret; } static int rx8025_write_regs(struct i2c_client *client, int number, u8 length, u8 *values) { int ret = i2c_smbus_write_i2c_block_data(client, (number << 4) | 0x08, length, values); if (ret) dev_err(&client->dev, "Unable to write registers #%d..#%d\n", number, number + length - 1); return ret; } static irqreturn_t rx8025_irq(int irq, void *dev_id) { struct i2c_client *client = dev_id; struct rx8025_data *rx8025 = i2c_get_clientdata(client); disable_irq_nosync(irq); schedule_work(&rx8025->work); return IRQ_HANDLED; } static void rx8025_work(struct work_struct *work) { struct rx8025_data *rx8025 = container_of(work, struct rx8025_data, work); struct i2c_client *client = rx8025->client; struct mutex *lock = &rx8025->rtc->ops_lock; u8 status; mutex_lock(lock); if (rx8025_read_reg(client, RX8025_REG_CTRL2, &status)) goto out; if (!(status & RX8025_BIT_CTRL2_XST)) dev_warn(&client->dev, "Oscillation stop was detected," "you may have to readjust the clock\n"); if (status & RX8025_BIT_CTRL2_CTFG) { /* periodic */ status &= ~RX8025_BIT_CTRL2_CTFG; local_irq_disable(); rtc_update_irq(rx8025->rtc, 1, RTC_PF | RTC_IRQF); local_irq_enable(); } if (status & RX8025_BIT_CTRL2_DAFG) { /* alarm */ status &= RX8025_BIT_CTRL2_DAFG; if (rx8025_write_reg(client, RX8025_REG_CTRL1, rx8025->ctrl1 & ~RX8025_BIT_CTRL1_DALE)) goto out; local_irq_disable(); rtc_update_irq(rx8025->rtc, 1, RTC_AF | RTC_IRQF); local_irq_enable(); } /* acknowledge IRQ */ rx8025_write_reg(client, RX8025_REG_CTRL2, status | RX8025_BIT_CTRL2_XST); out: if (!rx8025->exiting) enable_irq(client->irq); mutex_unlock(lock); } static int rx8025_get_time(struct device *dev, struct rtc_time *dt) { struct rx8025_data *rx8025 = dev_get_drvdata(dev); u8 date[7]; int err; err = rx8025_read_regs(rx8025->client, RX8025_REG_SEC, 7, date); if (err) return err; dev_dbg(dev, "%s: read 0x%02x 0x%02x " "0x%02x 0x%02x 0x%02x 0x%02x 0x%02x\n", __func__, date[0], date[1], date[2], date[3], date[4], date[5], date[6]); dt->tm_sec = bcd2bin(date[RX8025_REG_SEC] & 0x7f); dt->tm_min = bcd2bin(date[RX8025_REG_MIN] & 0x7f); if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224) dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x3f); else dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x1f) % 12 + (date[RX8025_REG_HOUR] & 0x20 ? 12 : 0); dt->tm_mday = bcd2bin(date[RX8025_REG_MDAY] & 0x3f); dt->tm_mon = bcd2bin(date[RX8025_REG_MONTH] & 0x1f) - 1; dt->tm_year = bcd2bin(date[RX8025_REG_YEAR]); if (dt->tm_year < 70) dt->tm_year += 100; dev_dbg(dev, "%s: date %ds %dm %dh %dmd %dm %dy\n", __func__, dt->tm_sec, dt->tm_min, dt->tm_hour, dt->tm_mday, dt->tm_mon, dt->tm_year); return rtc_valid_tm(dt); } static int rx8025_set_time(struct device *dev, struct rtc_time *dt) { struct rx8025_data *rx8025 = dev_get_drvdata(dev); u8 date[7]; /* * BUG: The HW assumes every year that is a multiple of 4 to be a leap * year. Next time this is wrong is 2100, which will not be a leap * year. */ /* * Here the read-only bits are written as "0". I'm not sure if that * is sound. */ date[RX8025_REG_SEC] = bin2bcd(dt->tm_sec); date[RX8025_REG_MIN] = bin2bcd(dt->tm_min); if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224) date[RX8025_REG_HOUR] = bin2bcd(dt->tm_hour); else date[RX8025_REG_HOUR] = (dt->tm_hour >= 12 ? 0x20 : 0) | bin2bcd((dt->tm_hour + 11) % 12 + 1); date[RX8025_REG_WDAY] = bin2bcd(dt->tm_wday); date[RX8025_REG_MDAY] = bin2bcd(dt->tm_mday); date[RX8025_REG_MONTH] = bin2bcd(dt->tm_mon + 1); date[RX8025_REG_YEAR] = bin2bcd(dt->tm_year % 100); dev_dbg(dev, "%s: write 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x\n", __func__, date[0], date[1], date[2], date[3], date[4], date[5], date[6]); return rx8025_write_regs(rx8025->client, RX8025_REG_SEC, 7, date); } static int rx8025_init_client(struct i2c_client *client, int *need_reset) { struct rx8025_data *rx8025 = i2c_get_clientdata(client); u8 ctrl[2], ctrl2; int need_clear = 0; int err; err = rx8025_read_regs(rx8025->client, RX8025_REG_CTRL1, 2, ctrl); if (err) goto out; /* Keep test bit zero ! */ rx8025->ctrl1 = ctrl[0] & ~RX8025_BIT_CTRL1_TEST; if (ctrl[1] & RX8025_BIT_CTRL2_PON) { dev_warn(&client->dev, "power-on reset was detected, " "you may have to readjust the clock\n"); *need_reset = 1; } if (ctrl[1] & RX8025_BIT_CTRL2_VDET) { dev_warn(&client->dev, "a power voltage drop was detected, " "you may have to readjust the clock\n"); *need_reset = 1; } if (!(ctrl[1] & RX8025_BIT_CTRL2_XST)) { dev_warn(&client->dev, "Oscillation stop was detected," "you may have to readjust the clock\n"); *need_reset = 1; } if (ctrl[1] & (RX8025_BIT_CTRL2_DAFG | RX8025_BIT_CTRL2_WAFG)) { dev_warn(&client->dev, "Alarm was detected\n"); need_clear = 1; } if (!(ctrl[1] & RX8025_BIT_CTRL2_CTFG)) need_clear = 1; if (*need_reset || need_clear) { ctrl2 = ctrl[0]; ctrl2 &= ~(RX8025_BIT_CTRL2_PON | RX8025_BIT_CTRL2_VDET | RX8025_BIT_CTRL2_CTFG | RX8025_BIT_CTRL2_WAFG | RX8025_BIT_CTRL2_DAFG); ctrl2 |= RX8025_BIT_CTRL2_XST; err = rx8025_write_reg(client, RX8025_REG_CTRL2, ctrl2); } out: return err; } /* Alarm support */ static int rx8025_read_alarm(struct device *dev, struct rtc_wkalrm *t) { struct rx8025_data *rx8025 = dev_get_drvdata(dev); struct i2c_client *client = rx8025->client; u8 ctrl2, ald[2]; int err; if (client->irq <= 0) return -EINVAL; err = rx8025_read_regs(client, RX8025_REG_ALDMIN, 2, ald); if (err) return err; err = rx8025_read_reg(client, RX8025_REG_CTRL2, &ctrl2); if (err) return err; dev_dbg(dev, "%s: read alarm 0x%02x 0x%02x ctrl2 %02x\n", __func__, ald[0], ald[1], ctrl2); /* Hardware alarms precision is 1 minute! */ t->time.tm_sec = 0; t->time.tm_min = bcd2bin(ald[0] & 0x7f); if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224) t->time.tm_hour = bcd2bin(ald[1] & 0x3f); else t->time.tm_hour = bcd2bin(ald[1] & 0x1f) % 12 + (ald[1] & 0x20 ? 12 : 0); t->time.tm_wday = -1; t->time.tm_mday = -1; t->time.tm_mon = -1; t->time.tm_year = -1; dev_dbg(dev, "%s: date: %ds %dm %dh %dmd %dm %dy\n", __func__, t->time.tm_sec, t->time.tm_min, t->time.tm_hour, t->time.tm_mday, t->time.tm_mon, t->time.tm_year); t->enabled = !!(rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE); t->pending = (ctrl2 & RX8025_BIT_CTRL2_DAFG) && t->enabled; return err; } static int rx8025_set_alarm(struct device *dev, struct rtc_wkalrm *t) { struct i2c_client *client = to_i2c_client(dev); struct rx8025_data *rx8025 = dev_get_drvdata(dev); u8 ald[2]; int err; if (client->irq <= 0) return -EINVAL; /* Hardware alarm precision is 1 minute! */ ald[0] = bin2bcd(t->time.tm_min); if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224) ald[1] = bin2bcd(t->time.tm_hour); else ald[1] = (t->time.tm_hour >= 12 ? 0x20 : 0) | bin2bcd((t->time.tm_hour + 11) % 12 + 1); dev_dbg(dev, "%s: write 0x%02x 0x%02x\n", __func__, ald[0], ald[1]); if (rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE) { rx8025->ctrl1 &= ~RX8025_BIT_CTRL1_DALE; err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1, rx8025->ctrl1); if (err) return err; } err = rx8025_write_regs(rx8025->client, RX8025_REG_ALDMIN, 2, ald); if (err) return err; if (t->enabled) { rx8025->ctrl1 |= RX8025_BIT_CTRL1_DALE; err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1, rx8025->ctrl1); if (err) return err; } return 0; } static int rx8025_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct rx8025_data *rx8025 = dev_get_drvdata(dev); u8 ctrl1; int err; ctrl1 = rx8025->ctrl1; if (enabled) ctrl1 |= RX8025_BIT_CTRL1_DALE; else ctrl1 &= ~RX8025_BIT_CTRL1_DALE; if (ctrl1 != rx8025->ctrl1) { rx8025->ctrl1 = ctrl1; err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1, rx8025->ctrl1); if (err) return err; } return 0; } static struct rtc_class_ops rx8025_rtc_ops = { .read_time = rx8025_get_time, .set_time = rx8025_set_time, .read_alarm = rx8025_read_alarm, .set_alarm = rx8025_set_alarm, .alarm_irq_enable = rx8025_alarm_irq_enable, }; /* * Clock precision adjustment support * * According to the RX8025 SA/NB application manual the frequency and * temperature characteristics can be approximated using the following * equation: * * df = a * (ut - t)**2 * * df: Frequency deviation in any temperature * a : Coefficient = (-35 +-5) * 10**-9 * ut: Ultimate temperature in degree = +25 +-5 degree * t : Any temperature in degree * * Note that the clock adjustment in ppb must be entered (which is * the negative value of the deviation). */ static int rx8025_get_clock_adjust(struct device *dev, int *adj) { struct i2c_client *client = to_i2c_client(dev); u8 digoff; int err; err = rx8025_read_reg(client, RX8025_REG_DIGOFF, &digoff); if (err) return err; *adj = digoff >= 64 ? digoff - 128 : digoff; if (*adj > 0) (*adj)--; *adj *= -RX8025_ADJ_RESOLUTION; return 0; } static int rx8025_set_clock_adjust(struct device *dev, int adj) { struct i2c_client *client = to_i2c_client(dev); u8 digoff; int err; adj /= -RX8025_ADJ_RESOLUTION; if (adj > RX8025_ADJ_DATA_MAX) adj = RX8025_ADJ_DATA_MAX; else if (adj < RX8025_ADJ_DATA_MIN) adj = RX8025_ADJ_DATA_MIN; else if (adj > 0) adj++; else if (adj < 0) adj += 128; digoff = adj; err = rx8025_write_reg(client, RX8025_REG_DIGOFF, digoff); if (err) return err; dev_dbg(dev, "%s: write 0x%02x\n", __func__, digoff); return 0; } static ssize_t rx8025_sysfs_show_clock_adjust(struct device *dev, struct device_attribute *attr, char *buf) { int err, adj; err = rx8025_get_clock_adjust(dev, &adj); if (err) return err; return sprintf(buf, "%d\n", adj); } static ssize_t rx8025_sysfs_store_clock_adjust(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { int adj, err; if (sscanf(buf, "%i", &adj) != 1) return -EINVAL; err = rx8025_set_clock_adjust(dev, adj); return err ? err : count; } static DEVICE_ATTR(clock_adjust_ppb, S_IRUGO | S_IWUSR, rx8025_sysfs_show_clock_adjust, rx8025_sysfs_store_clock_adjust); static int rx8025_sysfs_register(struct device *dev) { return device_create_file(dev, &dev_attr_clock_adjust_ppb); } static void rx8025_sysfs_unregister(struct device *dev) { device_remove_file(dev, &dev_attr_clock_adjust_ppb); } static int rx8025_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); struct rx8025_data *rx8025; int err, need_reset = 0; if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK)) { dev_err(&adapter->dev, "doesn't support required functionality\n"); err = -EIO; goto errout; } rx8025 = devm_kzalloc(&client->dev, sizeof(*rx8025), GFP_KERNEL); if (!rx8025) { err = -ENOMEM; goto errout; } rx8025->client = client; i2c_set_clientdata(client, rx8025); INIT_WORK(&rx8025->work, rx8025_work); err = rx8025_init_client(client, &need_reset); if (err) goto errout; if (need_reset) { struct rtc_time tm; dev_info(&client->dev, "bad conditions detected, resetting date\n"); rtc_time_to_tm(0, &tm); /* 1970/1/1 */ rx8025_set_time(&client->dev, &tm); } rx8025->rtc = devm_rtc_device_register(&client->dev, client->name, &rx8025_rtc_ops, THIS_MODULE); if (IS_ERR(rx8025->rtc)) { err = PTR_ERR(rx8025->rtc); dev_err(&client->dev, "unable to register the class device\n"); goto errout; } if (client->irq > 0) { dev_info(&client->dev, "IRQ %d supplied\n", client->irq); err = request_irq(client->irq, rx8025_irq, 0, "rx8025", client); if (err) { dev_err(&client->dev, "unable to request IRQ\n"); goto errout; } } rx8025->rtc->irq_freq = 1; rx8025->rtc->max_user_freq = 1; err = rx8025_sysfs_register(&client->dev); if (err) goto errout_irq; return 0; errout_irq: if (client->irq > 0) free_irq(client->irq, client); errout: dev_err(&adapter->dev, "probing for rx8025 failed\n"); return err; } static int rx8025_remove(struct i2c_client *client) { struct rx8025_data *rx8025 = i2c_get_clientdata(client); struct mutex *lock = &rx8025->rtc->ops_lock; if (client->irq > 0) { mutex_lock(lock); rx8025->exiting = 1; mutex_unlock(lock); free_irq(client->irq, client); cancel_work_sync(&rx8025->work); } rx8025_sysfs_unregister(&client->dev); return 0; } static struct i2c_driver rx8025_driver = { .driver = { .name = "rtc-rx8025", .owner = THIS_MODULE, }, .probe = rx8025_probe, .remove = rx8025_remove, .id_table = rx8025_id, }; module_i2c_driver(rx8025_driver); MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); MODULE_DESCRIPTION("RX-8025 SA/NB RTC driver"); MODULE_LICENSE("GPL");