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path: root/drivers/rtc/rtc-mv.c
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Diffstat (limited to 'drivers/rtc/rtc-mv.c')
-rw-r--r--drivers/rtc/rtc-mv.c163
1 files changed, 163 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-mv.c b/drivers/rtc/rtc-mv.c
new file mode 100644
index 000000000000..45f12dcd3716
--- /dev/null
+++ b/drivers/rtc/rtc-mv.c
@@ -0,0 +1,163 @@
+/*
+ * Driver for the RTC in Marvell SoCs.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/rtc.h>
+#include <linux/bcd.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+
+
+#define RTC_TIME_REG_OFFS 0
+#define RTC_SECONDS_OFFS 0
+#define RTC_MINUTES_OFFS 8
+#define RTC_HOURS_OFFS 16
+#define RTC_WDAY_OFFS 24
+#define RTC_HOURS_12H_MODE (1 << 22) /* 12 hours mode */
+
+#define RTC_DATE_REG_OFFS 4
+#define RTC_MDAY_OFFS 0
+#define RTC_MONTH_OFFS 8
+#define RTC_YEAR_OFFS 16
+
+
+struct rtc_plat_data {
+ struct rtc_device *rtc;
+ void __iomem *ioaddr;
+};
+
+static int mv_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+ void __iomem *ioaddr = pdata->ioaddr;
+ u32 rtc_reg;
+
+ rtc_reg = (bin2bcd(tm->tm_sec) << RTC_SECONDS_OFFS) |
+ (bin2bcd(tm->tm_min) << RTC_MINUTES_OFFS) |
+ (bin2bcd(tm->tm_hour) << RTC_HOURS_OFFS) |
+ (bin2bcd(tm->tm_wday) << RTC_WDAY_OFFS);
+ writel(rtc_reg, ioaddr + RTC_TIME_REG_OFFS);
+
+ rtc_reg = (bin2bcd(tm->tm_mday) << RTC_MDAY_OFFS) |
+ (bin2bcd(tm->tm_mon + 1) << RTC_MONTH_OFFS) |
+ (bin2bcd(tm->tm_year % 100) << RTC_YEAR_OFFS);
+ writel(rtc_reg, ioaddr + RTC_DATE_REG_OFFS);
+
+ return 0;
+}
+
+static int mv_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct rtc_plat_data *pdata = dev_get_drvdata(dev);
+ void __iomem *ioaddr = pdata->ioaddr;
+ u32 rtc_time, rtc_date;
+ unsigned int year, month, day, hour, minute, second, wday;
+
+ rtc_time = readl(ioaddr + RTC_TIME_REG_OFFS);
+ rtc_date = readl(ioaddr + RTC_DATE_REG_OFFS);
+
+ second = rtc_time & 0x7f;
+ minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f;
+ hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hours mode */
+ wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7;
+
+ day = rtc_date & 0x3f;
+ month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f;
+ year = (rtc_date >> RTC_YEAR_OFFS) & 0xff;
+
+ tm->tm_sec = bcd2bin(second);
+ tm->tm_min = bcd2bin(minute);
+ tm->tm_hour = bcd2bin(hour);
+ tm->tm_mday = bcd2bin(day);
+ tm->tm_wday = bcd2bin(wday);
+ tm->tm_mon = bcd2bin(month) - 1;
+ /* hw counts from year 2000, but tm_year is relative to 1900 */
+ tm->tm_year = bcd2bin(year) + 100;
+
+ return rtc_valid_tm(tm);
+}
+
+static const struct rtc_class_ops mv_rtc_ops = {
+ .read_time = mv_rtc_read_time,
+ .set_time = mv_rtc_set_time,
+};
+
+static int __init mv_rtc_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct rtc_plat_data *pdata;
+ resource_size_t size;
+ u32 rtc_time;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return -ENOMEM;
+
+ size = resource_size(res);
+ if (!devm_request_mem_region(&pdev->dev, res->start, size,
+ pdev->name))
+ return -EBUSY;
+
+ pdata->ioaddr = devm_ioremap(&pdev->dev, res->start, size);
+ if (!pdata->ioaddr)
+ return -ENOMEM;
+
+ /* make sure the 24 hours mode is enabled */
+ rtc_time = readl(pdata->ioaddr + RTC_TIME_REG_OFFS);
+ if (rtc_time & RTC_HOURS_12H_MODE) {
+ dev_err(&pdev->dev, "24 Hours mode not supported.\n");
+ return -EINVAL;
+ }
+
+ platform_set_drvdata(pdev, pdata);
+ pdata->rtc = rtc_device_register(pdev->name, &pdev->dev,
+ &mv_rtc_ops, THIS_MODULE);
+ if (IS_ERR(pdata->rtc))
+ return PTR_ERR(pdata->rtc);
+
+ return 0;
+}
+
+static int __exit mv_rtc_remove(struct platform_device *pdev)
+{
+ struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
+
+ rtc_device_unregister(pdata->rtc);
+ return 0;
+}
+
+static struct platform_driver mv_rtc_driver = {
+ .remove = __exit_p(mv_rtc_remove),
+ .driver = {
+ .name = "rtc-mv",
+ .owner = THIS_MODULE,
+ },
+};
+
+static __init int mv_init(void)
+{
+ return platform_driver_probe(&mv_rtc_driver, mv_rtc_probe);
+}
+
+static __exit void mv_exit(void)
+{
+ platform_driver_unregister(&mv_rtc_driver);
+}
+
+module_init(mv_init);
+module_exit(mv_exit);
+
+MODULE_AUTHOR("Saeed Bishara <saeed@marvell.com>");
+MODULE_DESCRIPTION("Marvell RTC driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:rtc-mv");