/* rtc-ds1343.c * * Driver for Dallas Semiconductor DS1343 Low Current, SPI Compatible * Real Time Clock * * Author : Raghavendra Chandra Ganiga <ravi23ganiga@gmail.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/init.h> #include <linux/module.h> #include <linux/interrupt.h> #include <linux/device.h> #include <linux/spi/spi.h> #include <linux/regmap.h> #include <linux/rtc.h> #include <linux/bcd.h> #include <linux/pm.h> #include <linux/slab.h> #define DS1343_DRV_VERSION "01.00" #define DALLAS_MAXIM_DS1343 0 #define DALLAS_MAXIM_DS1344 1 /* RTC DS1343 Registers */ #define DS1343_SECONDS_REG 0x00 #define DS1343_MINUTES_REG 0x01 #define DS1343_HOURS_REG 0x02 #define DS1343_DAY_REG 0x03 #define DS1343_DATE_REG 0x04 #define DS1343_MONTH_REG 0x05 #define DS1343_YEAR_REG 0x06 #define DS1343_ALM0_SEC_REG 0x07 #define DS1343_ALM0_MIN_REG 0x08 #define DS1343_ALM0_HOUR_REG 0x09 #define DS1343_ALM0_DAY_REG 0x0A #define DS1343_ALM1_SEC_REG 0x0B #define DS1343_ALM1_MIN_REG 0x0C #define DS1343_ALM1_HOUR_REG 0x0D #define DS1343_ALM1_DAY_REG 0x0E #define DS1343_CONTROL_REG 0x0F #define DS1343_STATUS_REG 0x10 #define DS1343_TRICKLE_REG 0x11 /* DS1343 Control Registers bits */ #define DS1343_EOSC 0x80 #define DS1343_DOSF 0x20 #define DS1343_EGFIL 0x10 #define DS1343_SQW 0x08 #define DS1343_INTCN 0x04 #define DS1343_A1IE 0x02 #define DS1343_A0IE 0x01 /* DS1343 Status Registers bits */ #define DS1343_OSF 0x80 #define DS1343_IRQF1 0x02 #define DS1343_IRQF0 0x01 /* DS1343 Trickle Charger Registers bits */ #define DS1343_TRICKLE_MAGIC 0xa0 #define DS1343_TRICKLE_DS1 0x08 #define DS1343_TRICKLE_1K 0x01 #define DS1343_TRICKLE_2K 0x02 #define DS1343_TRICKLE_4K 0x03 static const struct spi_device_id ds1343_id[] = { { "ds1343", DALLAS_MAXIM_DS1343 }, { "ds1344", DALLAS_MAXIM_DS1344 }, { } }; MODULE_DEVICE_TABLE(spi, ds1343_id); struct ds1343_priv { struct spi_device *spi; struct rtc_device *rtc; struct regmap *map; struct mutex mutex; unsigned int irqen; int irq; int alarm_sec; int alarm_min; int alarm_hour; int alarm_mday; }; static int ds1343_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) { switch (cmd) { #ifdef RTC_SET_CHARGE case RTC_SET_CHARGE: { int val; if (copy_from_user(&val, (int __user *)arg, sizeof(int))) return -EFAULT; return regmap_write(priv->map, DS1343_TRICKLE_REG, val); } break; #endif } return -ENOIOCTLCMD; } static ssize_t ds1343_show_glitchfilter(struct device *dev, struct device_attribute *attr, char *buf) { struct ds1343_priv *priv = dev_get_drvdata(dev); int glitch_filt_status, data; regmap_read(priv->map, DS1343_CONTROL_REG, &data); glitch_filt_status = !!(data & DS1343_EGFIL); if (glitch_filt_status) return sprintf(buf, "enabled\n"); else return sprintf(buf, "disabled\n"); } static ssize_t ds1343_store_glitchfilter(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct ds1343_priv *priv = dev_get_drvdata(dev); int data; regmap_read(priv->map, DS1343_CONTROL_REG, &data); if (strncmp(buf, "enabled", 7) == 0) data |= DS1343_EGFIL; else if (strncmp(buf, "disabled", 8) == 0) data &= ~(DS1343_EGFIL); else return -EINVAL; regmap_write(priv->map, DS1343_CONTROL_REG, data); return count; } static DEVICE_ATTR(glitch_filter, S_IRUGO | S_IWUSR, ds1343_show_glitchfilter, ds1343_store_glitchfilter); static ssize_t ds1343_show_alarmstatus(struct device *dev, struct device_attribute *attr, char *buf) { struct ds1343_priv *priv = dev_get_drvdata(dev); int alarmstatus, data; regmap_read(priv->map, DS1343_CONTROL_REG, &data); alarmstatus = !!(data & DS1343_A0IE); if (alarmstatus) return sprintf(buf, "enabled\n"); else return sprintf(buf, "disabled\n"); } static DEVICE_ATTR(alarm_status, S_IRUGO, ds1343_show_alarmstatus, NULL); static ssize_t ds1343_show_alarmmode(struct device *dev, struct device_attribute *attr, char *buf) { struct ds1343_priv *priv = dev_get_drvdata(dev); int alarm_mode, data; char *alarm_str; regmap_read(priv->map, DS1343_ALM0_SEC_REG, &data); alarm_mode = (data & 0x80) >> 4; regmap_read(priv->map, DS1343_ALM0_MIN_REG, &data); alarm_mode |= (data & 0x80) >> 5; regmap_read(priv->map, DS1343_ALM0_HOUR_REG, &data); alarm_mode |= (data & 0x80) >> 6; regmap_read(priv->map, DS1343_ALM0_DAY_REG, &data); alarm_mode |= (data & 0x80) >> 7; switch (alarm_mode) { case 15: alarm_str = "each second"; break; case 7: alarm_str = "seconds match"; break; case 3: alarm_str = "minutes and seconds match"; break; case 1: alarm_str = "hours, minutes and seconds match"; break; case 0: alarm_str = "day, hours, minutes and seconds match"; break; default: alarm_str = "invalid"; break; } return sprintf(buf, "%s\n", alarm_str); } static DEVICE_ATTR(alarm_mode, S_IRUGO, ds1343_show_alarmmode, NULL); static ssize_t ds1343_show_tricklecharger(struct device *dev, struct device_attribute *attr, char *buf) { struct ds1343_priv *priv = dev_get_drvdata(dev); int data; char *diodes = "disabled", *resistors = " "; regmap_read(priv->map, DS1343_TRICKLE_REG, &data); if ((data & 0xf0) == DS1343_TRICKLE_MAGIC) { switch (data & 0x0c) { case DS1343_TRICKLE_DS1: diodes = "one diode,"; break; default: diodes = "no diode,"; break; } switch (data & 0x03) { case DS1343_TRICKLE_1K: resistors = "1k Ohm"; break; case DS1343_TRICKLE_2K: resistors = "2k Ohm"; break; case DS1343_TRICKLE_4K: resistors = "4k Ohm"; break; default: diodes = "disabled"; break; } } return sprintf(buf, "%s %s\n", diodes, resistors); } static DEVICE_ATTR(trickle_charger, S_IRUGO, ds1343_show_tricklecharger, NULL); static int ds1343_sysfs_register(struct device *dev) { struct ds1343_priv *priv = dev_get_drvdata(dev); int err; err = device_create_file(dev, &dev_attr_glitch_filter); if (err) return err; err = device_create_file(dev, &dev_attr_trickle_charger); if (err) goto error1; if (priv->irq <= 0) return err; err = device_create_file(dev, &dev_attr_alarm_mode); if (err) goto error2; err = device_create_file(dev, &dev_attr_alarm_status); if (!err) return err; device_remove_file(dev, &dev_attr_alarm_mode); error2: device_remove_file(dev, &dev_attr_trickle_charger); error1: device_remove_file(dev, &dev_attr_glitch_filter); return err; } static void ds1343_sysfs_unregister(struct device *dev) { struct ds1343_priv *priv = dev_get_drvdata(dev); device_remove_file(dev, &dev_attr_glitch_filter); device_remove_file(dev, &dev_attr_trickle_charger); if (priv->irq <= 0) return; device_remove_file(dev, &dev_attr_alarm_status); device_remove_file(dev, &dev_attr_alarm_mode); } static int ds1343_read_time(struct device *dev, struct rtc_time *dt) { struct ds1343_priv *priv = dev_get_drvdata(dev); unsigned char buf[7]; int res; res = regmap_bulk_read(priv->map, DS1343_SECONDS_REG, buf, 7); if (res) return res; dt->tm_sec = bcd2bin(buf[0]); dt->tm_min = bcd2bin(buf[1]); dt->tm_hour = bcd2bin(buf[2] & 0x3F); dt->tm_wday = bcd2bin(buf[3]) - 1; dt->tm_mday = bcd2bin(buf[4]); dt->tm_mon = bcd2bin(buf[5] & 0x1F) - 1; dt->tm_year = bcd2bin(buf[6]) + 100; /* year offset from 1900 */ return rtc_valid_tm(dt); } static int ds1343_set_time(struct device *dev, struct rtc_time *dt) { struct ds1343_priv *priv = dev_get_drvdata(dev); int res; res = regmap_write(priv->map, DS1343_SECONDS_REG, bin2bcd(dt->tm_sec)); if (res) return res; res = regmap_write(priv->map, DS1343_MINUTES_REG, bin2bcd(dt->tm_min)); if (res) return res; res = regmap_write(priv->map, DS1343_HOURS_REG, bin2bcd(dt->tm_hour) & 0x3F); if (res) return res; res = regmap_write(priv->map, DS1343_DAY_REG, bin2bcd(dt->tm_wday + 1)); if (res) return res; res = regmap_write(priv->map, DS1343_DATE_REG, bin2bcd(dt->tm_mday)); if (res) return res; res = regmap_write(priv->map, DS1343_MONTH_REG, bin2bcd(dt->tm_mon + 1)); if (res) return res; dt->tm_year %= 100; res = regmap_write(priv->map, DS1343_YEAR_REG, bin2bcd(dt->tm_year)); if (res) return res; return 0; } static int ds1343_update_alarm(struct device *dev) { struct ds1343_priv *priv = dev_get_drvdata(dev); unsigned int control, stat; unsigned char buf[4]; int res = 0; res = regmap_read(priv->map, DS1343_CONTROL_REG, &control); if (res) return res; res = regmap_read(priv->map, DS1343_STATUS_REG, &stat); if (res) return res; control &= ~(DS1343_A0IE); stat &= ~(DS1343_IRQF0); res = regmap_write(priv->map, DS1343_CONTROL_REG, control); if (res) return res; res = regmap_write(priv->map, DS1343_STATUS_REG, stat); if (res) return res; buf[0] = priv->alarm_sec < 0 || (priv->irqen & RTC_UF) ? 0x80 : bin2bcd(priv->alarm_sec) & 0x7F; buf[1] = priv->alarm_min < 0 || (priv->irqen & RTC_UF) ? 0x80 : bin2bcd(priv->alarm_min) & 0x7F; buf[2] = priv->alarm_hour < 0 || (priv->irqen & RTC_UF) ? 0x80 : bin2bcd(priv->alarm_hour) & 0x3F; buf[3] = priv->alarm_mday < 0 || (priv->irqen & RTC_UF) ? 0x80 : bin2bcd(priv->alarm_mday) & 0x7F; res = regmap_bulk_write(priv->map, DS1343_ALM0_SEC_REG, buf, 4); if (res) return res; if (priv->irqen) { control |= DS1343_A0IE; res = regmap_write(priv->map, DS1343_CONTROL_REG, control); } return res; } static int ds1343_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) { struct ds1343_priv *priv = dev_get_drvdata(dev); int res = 0; unsigned int stat; if (priv->irq <= 0) return -EINVAL; mutex_lock(&priv->mutex); res = regmap_read(priv->map, DS1343_STATUS_REG, &stat); if (res) goto out; alarm->enabled = !!(priv->irqen & RTC_AF); alarm->pending = !!(stat & DS1343_IRQF0); alarm->time.tm_sec = priv->alarm_sec < 0 ? 0 : priv->alarm_sec; alarm->time.tm_min = priv->alarm_min < 0 ? 0 : priv->alarm_min; alarm->time.tm_hour = priv->alarm_hour < 0 ? 0 : priv->alarm_hour; alarm->time.tm_mday = priv->alarm_mday < 0 ? 0 : priv->alarm_mday; alarm->time.tm_mon = -1; alarm->time.tm_year = -1; alarm->time.tm_wday = -1; alarm->time.tm_yday = -1; alarm->time.tm_isdst = -1; out: mutex_unlock(&priv->mutex); return res; } static int ds1343_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) { struct ds1343_priv *priv = dev_get_drvdata(dev); int res = 0; if (priv->irq <= 0) return -EINVAL; mutex_lock(&priv->mutex); priv->alarm_sec = alarm->time.tm_sec; priv->alarm_min = alarm->time.tm_min; priv->alarm_hour = alarm->time.tm_hour; priv->alarm_mday = alarm->time.tm_mday; if (alarm->enabled) priv->irqen |= RTC_AF; res = ds1343_update_alarm(dev); mutex_unlock(&priv->mutex); return res; } static int ds1343_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct ds1343_priv *priv = dev_get_drvdata(dev); int res = 0; if (priv->irq <= 0) return -EINVAL; mutex_lock(&priv->mutex); if (enabled) priv->irqen |= RTC_AF; else priv->irqen &= ~RTC_AF; res = ds1343_update_alarm(dev); mutex_unlock(&priv->mutex); return res; } static irqreturn_t ds1343_thread(int irq, void *dev_id) { struct ds1343_priv *priv = dev_id; unsigned int stat, control; int res = 0; mutex_lock(&priv->mutex); res = regmap_read(priv->map, DS1343_STATUS_REG, &stat); if (res) goto out; if (stat & DS1343_IRQF0) { stat &= ~DS1343_IRQF0; regmap_write(priv->map, DS1343_STATUS_REG, stat); res = regmap_read(priv->map, DS1343_CONTROL_REG, &control); if (res) goto out; control &= ~DS1343_A0IE; regmap_write(priv->map, DS1343_CONTROL_REG, control); rtc_update_irq(priv->rtc, 1, RTC_AF | RTC_IRQF); } out: mutex_unlock(&priv->mutex); return IRQ_HANDLED; } static const struct rtc_class_ops ds1343_rtc_ops = { .ioctl = ds1343_ioctl, .read_time = ds1343_read_time, .set_time = ds1343_set_time, .read_alarm = ds1343_read_alarm, .set_alarm = ds1343_set_alarm, .alarm_irq_enable = ds1343_alarm_irq_enable, }; static int ds1343_probe(struct spi_device *spi) { struct ds1343_priv *priv; struct regmap_config config; unsigned int data; int res; memset(&config, 0, sizeof(config)); config.reg_bits = 8; config.val_bits = 8; config.write_flag_mask = 0x80; priv = devm_kzalloc(&spi->dev, sizeof(struct ds1343_priv), GFP_KERNEL); if (!priv) return -ENOMEM; priv->spi = spi; mutex_init(&priv->mutex); /* RTC DS1347 works in spi mode 3 and * its chip select is active high */ spi->mode = SPI_MODE_3 | SPI_CS_HIGH; spi->bits_per_word = 8; res = spi_setup(spi); if (res) return res; spi_set_drvdata(spi, priv); priv->map = devm_regmap_init_spi(spi, &config); if (IS_ERR(priv->map)) { dev_err(&spi->dev, "spi regmap init failed for rtc ds1343\n"); return PTR_ERR(priv->map); } res = regmap_read(priv->map, DS1343_SECONDS_REG, &data); if (res) return res; regmap_read(priv->map, DS1343_CONTROL_REG, &data); data |= DS1343_INTCN; data &= ~(DS1343_EOSC | DS1343_A1IE | DS1343_A0IE); regmap_write(priv->map, DS1343_CONTROL_REG, data); regmap_read(priv->map, DS1343_STATUS_REG, &data); data &= ~(DS1343_OSF | DS1343_IRQF1 | DS1343_IRQF0); regmap_write(priv->map, DS1343_STATUS_REG, data); priv->rtc = devm_rtc_device_register(&spi->dev, "ds1343", &ds1343_rtc_ops, THIS_MODULE); if (IS_ERR(priv->rtc)) { dev_err(&spi->dev, "unable to register rtc ds1343\n"); return PTR_ERR(priv->rtc); } priv->irq = spi->irq; if (priv->irq >= 0) { res = devm_request_threaded_irq(&spi->dev, spi->irq, NULL, ds1343_thread, IRQF_NO_SUSPEND | IRQF_ONESHOT, "ds1343", priv); if (res) { priv->irq = -1; dev_err(&spi->dev, "unable to request irq for rtc ds1343\n"); } else { device_set_wakeup_capable(&spi->dev, 1); } } res = ds1343_sysfs_register(&spi->dev); if (res) dev_err(&spi->dev, "unable to create sysfs entries for rtc ds1343\n"); return 0; } static int ds1343_remove(struct spi_device *spi) { struct ds1343_priv *priv = spi_get_drvdata(spi); if (spi->irq) { mutex_lock(&priv->mutex); priv->irqen &= ~RTC_AF; mutex_unlock(&priv->mutex); devm_free_irq(&spi->dev, spi->irq, priv); } spi_set_drvdata(spi, NULL); ds1343_sysfs_unregister(&spi->dev); return 0; } #ifdef CONFIG_PM_SLEEP static int ds1343_suspend(struct device *dev) { struct spi_device *spi = to_spi_device(dev); if (spi->irq >= 0 && device_may_wakeup(dev)) enable_irq_wake(spi->irq); return 0; } static int ds1343_resume(struct device *dev) { struct spi_device *spi = to_spi_device(dev); if (spi->irq >= 0 && device_may_wakeup(dev)) disable_irq_wake(spi->irq); return 0; } #endif static SIMPLE_DEV_PM_OPS(ds1343_pm, ds1343_suspend, ds1343_resume); static struct spi_driver ds1343_driver = { .driver = { .name = "ds1343", .owner = THIS_MODULE, .pm = &ds1343_pm, }, .probe = ds1343_probe, .remove = ds1343_remove, .id_table = ds1343_id, }; module_spi_driver(ds1343_driver); MODULE_DESCRIPTION("DS1343 RTC SPI Driver"); MODULE_AUTHOR("Raghavendra Chandra Ganiga <ravi23ganiga@gmail.com>"); MODULE_LICENSE("GPL v2"); MODULE_VERSION(DS1343_DRV_VERSION);