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path: root/drivers/rtc/rtc-max8925.c
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Diffstat (limited to 'drivers/rtc/rtc-max8925.c')
-rw-r--r--drivers/rtc/rtc-max8925.c322
1 files changed, 322 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-max8925.c b/drivers/rtc/rtc-max8925.c
new file mode 100644
index 000000000..64bb8ac6e
--- /dev/null
+++ b/drivers/rtc/rtc-max8925.c
@@ -0,0 +1,322 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * RTC driver for Maxim MAX8925
+ *
+ * Copyright (C) 2009-2010 Marvell International Ltd.
+ * Haojian Zhuang <haojian.zhuang@marvell.com>
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+#include <linux/rtc.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/max8925.h>
+
+enum {
+ RTC_SEC = 0,
+ RTC_MIN,
+ RTC_HOUR,
+ RTC_WEEKDAY,
+ RTC_DATE,
+ RTC_MONTH,
+ RTC_YEAR1,
+ RTC_YEAR2,
+};
+
+#define MAX8925_RTC_SEC 0x00
+#define MAX8925_RTC_MIN 0x01
+#define MAX8925_RTC_HOUR 0x02
+#define MAX8925_RTC_WEEKDAY 0x03
+#define MAX8925_RTC_DATE 0x04
+#define MAX8925_RTC_MONTH 0x05
+#define MAX8925_RTC_YEAR1 0x06
+#define MAX8925_RTC_YEAR2 0x07
+#define MAX8925_ALARM0_SEC 0x08
+#define MAX8925_ALARM0_MIN 0x09
+#define MAX8925_ALARM0_HOUR 0x0a
+#define MAX8925_ALARM0_WEEKDAY 0x0b
+#define MAX8925_ALARM0_DATE 0x0c
+#define MAX8925_ALARM0_MON 0x0d
+#define MAX8925_ALARM0_YEAR1 0x0e
+#define MAX8925_ALARM0_YEAR2 0x0f
+#define MAX8925_ALARM1_SEC 0x10
+#define MAX8925_ALARM1_MIN 0x11
+#define MAX8925_ALARM1_HOUR 0x12
+#define MAX8925_ALARM1_WEEKDAY 0x13
+#define MAX8925_ALARM1_DATE 0x14
+#define MAX8925_ALARM1_MON 0x15
+#define MAX8925_ALARM1_YEAR1 0x16
+#define MAX8925_ALARM1_YEAR2 0x17
+#define MAX8925_RTC_CNTL 0x1b
+#define MAX8925_RTC_STATUS 0x20
+
+#define TIME_NUM 8
+#define ALARM_1SEC (1 << 7)
+#define HOUR_12 (1 << 7)
+#define HOUR_AM_PM (1 << 5)
+#define ALARM0_IRQ (1 << 3)
+#define ALARM1_IRQ (1 << 2)
+#define ALARM0_STATUS (1 << 2)
+#define ALARM1_STATUS (1 << 1)
+
+
+struct max8925_rtc_info {
+ struct rtc_device *rtc_dev;
+ struct max8925_chip *chip;
+ struct i2c_client *rtc;
+ struct device *dev;
+ int irq;
+};
+
+static irqreturn_t rtc_update_handler(int irq, void *data)
+{
+ struct max8925_rtc_info *info = (struct max8925_rtc_info *)data;
+
+ /* disable ALARM0 except for 1SEC alarm */
+ max8925_set_bits(info->rtc, MAX8925_ALARM0_CNTL, 0x7f, 0);
+ rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);
+ return IRQ_HANDLED;
+}
+
+static int tm_calc(struct rtc_time *tm, unsigned char *buf, int len)
+{
+ if (len < TIME_NUM)
+ return -EINVAL;
+ tm->tm_year = (buf[RTC_YEAR2] >> 4) * 1000
+ + (buf[RTC_YEAR2] & 0xf) * 100
+ + (buf[RTC_YEAR1] >> 4) * 10
+ + (buf[RTC_YEAR1] & 0xf);
+ tm->tm_year -= 1900;
+ tm->tm_mon = ((buf[RTC_MONTH] >> 4) & 0x01) * 10
+ + (buf[RTC_MONTH] & 0x0f);
+ tm->tm_mday = ((buf[RTC_DATE] >> 4) & 0x03) * 10
+ + (buf[RTC_DATE] & 0x0f);
+ tm->tm_wday = buf[RTC_WEEKDAY] & 0x07;
+ if (buf[RTC_HOUR] & HOUR_12) {
+ tm->tm_hour = ((buf[RTC_HOUR] >> 4) & 0x1) * 10
+ + (buf[RTC_HOUR] & 0x0f);
+ if (buf[RTC_HOUR] & HOUR_AM_PM)
+ tm->tm_hour += 12;
+ } else
+ tm->tm_hour = ((buf[RTC_HOUR] >> 4) & 0x03) * 10
+ + (buf[RTC_HOUR] & 0x0f);
+ tm->tm_min = ((buf[RTC_MIN] >> 4) & 0x7) * 10
+ + (buf[RTC_MIN] & 0x0f);
+ tm->tm_sec = ((buf[RTC_SEC] >> 4) & 0x7) * 10
+ + (buf[RTC_SEC] & 0x0f);
+ return 0;
+}
+
+static int data_calc(unsigned char *buf, struct rtc_time *tm, int len)
+{
+ unsigned char high, low;
+
+ if (len < TIME_NUM)
+ return -EINVAL;
+
+ high = (tm->tm_year + 1900) / 1000;
+ low = (tm->tm_year + 1900) / 100;
+ low = low - high * 10;
+ buf[RTC_YEAR2] = (high << 4) + low;
+ high = (tm->tm_year + 1900) / 10;
+ low = tm->tm_year + 1900;
+ low = low - high * 10;
+ high = high - (high / 10) * 10;
+ buf[RTC_YEAR1] = (high << 4) + low;
+ high = tm->tm_mon / 10;
+ low = tm->tm_mon;
+ low = low - high * 10;
+ buf[RTC_MONTH] = (high << 4) + low;
+ high = tm->tm_mday / 10;
+ low = tm->tm_mday;
+ low = low - high * 10;
+ buf[RTC_DATE] = (high << 4) + low;
+ buf[RTC_WEEKDAY] = tm->tm_wday;
+ high = tm->tm_hour / 10;
+ low = tm->tm_hour;
+ low = low - high * 10;
+ buf[RTC_HOUR] = (high << 4) + low;
+ high = tm->tm_min / 10;
+ low = tm->tm_min;
+ low = low - high * 10;
+ buf[RTC_MIN] = (high << 4) + low;
+ high = tm->tm_sec / 10;
+ low = tm->tm_sec;
+ low = low - high * 10;
+ buf[RTC_SEC] = (high << 4) + low;
+ return 0;
+}
+
+static int max8925_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct max8925_rtc_info *info = dev_get_drvdata(dev);
+ unsigned char buf[TIME_NUM];
+ int ret;
+
+ ret = max8925_bulk_read(info->rtc, MAX8925_RTC_SEC, TIME_NUM, buf);
+ if (ret < 0)
+ goto out;
+ ret = tm_calc(tm, buf, TIME_NUM);
+out:
+ return ret;
+}
+
+static int max8925_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct max8925_rtc_info *info = dev_get_drvdata(dev);
+ unsigned char buf[TIME_NUM];
+ int ret;
+
+ ret = data_calc(buf, tm, TIME_NUM);
+ if (ret < 0)
+ goto out;
+ ret = max8925_bulk_write(info->rtc, MAX8925_RTC_SEC, TIME_NUM, buf);
+out:
+ return ret;
+}
+
+static int max8925_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct max8925_rtc_info *info = dev_get_drvdata(dev);
+ unsigned char buf[TIME_NUM];
+ int ret;
+
+ ret = max8925_bulk_read(info->rtc, MAX8925_ALARM0_SEC, TIME_NUM, buf);
+ if (ret < 0)
+ goto out;
+ ret = tm_calc(&alrm->time, buf, TIME_NUM);
+ if (ret < 0)
+ goto out;
+ ret = max8925_reg_read(info->rtc, MAX8925_RTC_IRQ_MASK);
+ if (ret < 0)
+ goto out;
+ if (ret & ALARM0_IRQ) {
+ alrm->enabled = 0;
+ } else {
+ ret = max8925_reg_read(info->rtc, MAX8925_ALARM0_CNTL);
+ if (ret < 0)
+ goto out;
+ if (!ret)
+ alrm->enabled = 0;
+ else
+ alrm->enabled = 1;
+ }
+ ret = max8925_reg_read(info->rtc, MAX8925_RTC_STATUS);
+ if (ret < 0)
+ goto out;
+ if (ret & ALARM0_STATUS)
+ alrm->pending = 1;
+ else
+ alrm->pending = 0;
+ return 0;
+out:
+ return ret;
+}
+
+static int max8925_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct max8925_rtc_info *info = dev_get_drvdata(dev);
+ unsigned char buf[TIME_NUM];
+ int ret;
+
+ ret = data_calc(buf, &alrm->time, TIME_NUM);
+ if (ret < 0)
+ goto out;
+ ret = max8925_bulk_write(info->rtc, MAX8925_ALARM0_SEC, TIME_NUM, buf);
+ if (ret < 0)
+ goto out;
+ if (alrm->enabled)
+ /* only enable alarm on year/month/day/hour/min/sec */
+ ret = max8925_reg_write(info->rtc, MAX8925_ALARM0_CNTL, 0x77);
+ else
+ ret = max8925_reg_write(info->rtc, MAX8925_ALARM0_CNTL, 0x0);
+out:
+ return ret;
+}
+
+static const struct rtc_class_ops max8925_rtc_ops = {
+ .read_time = max8925_rtc_read_time,
+ .set_time = max8925_rtc_set_time,
+ .read_alarm = max8925_rtc_read_alarm,
+ .set_alarm = max8925_rtc_set_alarm,
+};
+
+static int max8925_rtc_probe(struct platform_device *pdev)
+{
+ struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
+ struct max8925_rtc_info *info;
+ int ret;
+
+ info = devm_kzalloc(&pdev->dev, sizeof(struct max8925_rtc_info),
+ GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+ info->chip = chip;
+ info->rtc = chip->rtc;
+ info->dev = &pdev->dev;
+ info->irq = platform_get_irq(pdev, 0);
+
+ ret = devm_request_threaded_irq(&pdev->dev, info->irq, NULL,
+ rtc_update_handler, IRQF_ONESHOT,
+ "rtc-alarm0", info);
+ if (ret < 0) {
+ dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
+ info->irq, ret);
+ return ret;
+ }
+
+ dev_set_drvdata(&pdev->dev, info);
+ /* XXX - isn't this redundant? */
+ platform_set_drvdata(pdev, info);
+
+ device_init_wakeup(&pdev->dev, 1);
+
+ info->rtc_dev = devm_rtc_device_register(&pdev->dev, "max8925-rtc",
+ &max8925_rtc_ops, THIS_MODULE);
+ ret = PTR_ERR(info->rtc_dev);
+ if (IS_ERR(info->rtc_dev)) {
+ dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int max8925_rtc_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
+
+ if (device_may_wakeup(dev))
+ chip->wakeup_flag |= 1 << MAX8925_IRQ_RTC_ALARM0;
+ return 0;
+}
+static int max8925_rtc_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);
+
+ if (device_may_wakeup(dev))
+ chip->wakeup_flag &= ~(1 << MAX8925_IRQ_RTC_ALARM0);
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(max8925_rtc_pm_ops, max8925_rtc_suspend, max8925_rtc_resume);
+
+static struct platform_driver max8925_rtc_driver = {
+ .driver = {
+ .name = "max8925-rtc",
+ .pm = &max8925_rtc_pm_ops,
+ },
+ .probe = max8925_rtc_probe,
+};
+
+module_platform_driver(max8925_rtc_driver);
+
+MODULE_DESCRIPTION("Maxim MAX8925 RTC driver");
+MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
+MODULE_LICENSE("GPL");
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 09:54:23 +0000