--- /dev/null
+/* 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 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)
+{
+ int err;
+
+ err = device_create_file(dev, &dev_attr_glitch_filter);
+ if (err)
+ return err;
+
+ err = device_create_file(dev, &dev_attr_alarm_status);
+ if (err)
+ goto error1;
+
+ err = device_create_file(dev, &dev_attr_alarm_mode);
+ if (err)
+ goto error2;
+
+ err = device_create_file(dev, &dev_attr_trickle_charger);
+ if (!err)
+ return err;
+
+ device_remove_file(dev, &dev_attr_alarm_mode);
+
+error2:
+ device_remove_file(dev, &dev_attr_alarm_status);
+
+error1:
+ device_remove_file(dev, &dev_attr_glitch_filter);
+
+ return err;
+}
+
+static void ds1343_sysfs_unregister(struct device *dev)
+{
+ device_remove_file(dev, &dev_attr_glitch_filter);
+ device_remove_file(dev, &dev_attr_alarm_status);
+ device_remove_file(dev, &dev_attr_alarm_mode);
+ device_remove_file(dev, &dev_attr_trickle_charger);
+}
+
+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);
+ struct spi_device *spi = priv->spi;
+ int res = 0;
+ unsigned int stat;
+
+ if (spi->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);
+ struct spi_device *spi = priv->spi;
+ int res = 0;
+
+ if (spi->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);
+ struct spi_device *spi = priv->spi;
+ int res = 0;
+
+ if (spi->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);
+ }
+
+ if (spi->irq >= 0) {
+ res = devm_request_threaded_irq(&spi->dev, spi->irq, NULL,
+ ds1343_thread,
+ IRQF_NO_SUSPEND | IRQF_ONESHOT,
+ "ds1343", priv);
+ if (res) {
+ dev_err(&spi->dev,
+ "unable to request irq for rtc ds1343\n");
+ return res;
+ }
+
+ 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);
projects / cascardo / linux.git / commitdiff