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path: root/drivers/rtc/rtc-ftrtc010.c
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Diffstat (limited to 'drivers/rtc/rtc-ftrtc010.c')
-rw-r--r--drivers/rtc/rtc-ftrtc010.c222
1 files changed, 222 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-ftrtc010.c b/drivers/rtc/rtc-ftrtc010.c
new file mode 100644
index 000000000..25c6e7d95
--- /dev/null
+++ b/drivers/rtc/rtc-ftrtc010.c
@@ -0,0 +1,222 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Faraday Technology FTRTC010 driver
+ *
+ * Copyright (C) 2009 Janos Laube <janos.dev@gmail.com>
+ *
+ * Original code for older kernel 2.6.15 are from Stormlinksemi
+ * first update from Janos Laube for > 2.6.29 kernels
+ *
+ * checkpatch fixes and usage of rtc-lib code
+ * Hans Ulli Kroll <ulli.kroll@googlemail.com>
+ */
+
+#include <linux/rtc.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/clk.h>
+
+#define DRV_NAME "rtc-ftrtc010"
+
+MODULE_AUTHOR("Hans Ulli Kroll <ulli.kroll@googlemail.com>");
+MODULE_DESCRIPTION("RTC driver for Gemini SoC");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRV_NAME);
+
+struct ftrtc010_rtc {
+ struct rtc_device *rtc_dev;
+ void __iomem *rtc_base;
+ int rtc_irq;
+ struct clk *pclk;
+ struct clk *extclk;
+};
+
+enum ftrtc010_rtc_offsets {
+ FTRTC010_RTC_SECOND = 0x00,
+ FTRTC010_RTC_MINUTE = 0x04,
+ FTRTC010_RTC_HOUR = 0x08,
+ FTRTC010_RTC_DAYS = 0x0C,
+ FTRTC010_RTC_ALARM_SECOND = 0x10,
+ FTRTC010_RTC_ALARM_MINUTE = 0x14,
+ FTRTC010_RTC_ALARM_HOUR = 0x18,
+ FTRTC010_RTC_RECORD = 0x1C,
+ FTRTC010_RTC_CR = 0x20,
+};
+
+static irqreturn_t ftrtc010_rtc_interrupt(int irq, void *dev)
+{
+ return IRQ_HANDLED;
+}
+
+/*
+ * Looks like the RTC in the Gemini SoC is (totaly) broken
+ * We can't read/write directly the time from RTC registers.
+ * We must do some "offset" calculation to get the real time
+ *
+ * This FIX works pretty fine and Stormlinksemi aka Cortina-Networks does
+ * the same thing, without the rtc-lib.c calls.
+ */
+
+static int ftrtc010_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct ftrtc010_rtc *rtc = dev_get_drvdata(dev);
+
+ u32 days, hour, min, sec, offset;
+ timeu64_t time;
+
+ sec = readl(rtc->rtc_base + FTRTC010_RTC_SECOND);
+ min = readl(rtc->rtc_base + FTRTC010_RTC_MINUTE);
+ hour = readl(rtc->rtc_base + FTRTC010_RTC_HOUR);
+ days = readl(rtc->rtc_base + FTRTC010_RTC_DAYS);
+ offset = readl(rtc->rtc_base + FTRTC010_RTC_RECORD);
+
+ time = offset + days * 86400 + hour * 3600 + min * 60 + sec;
+
+ rtc_time64_to_tm(time, tm);
+
+ return 0;
+}
+
+static int ftrtc010_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct ftrtc010_rtc *rtc = dev_get_drvdata(dev);
+ u32 sec, min, hour, day, offset;
+ timeu64_t time;
+
+ time = rtc_tm_to_time64(tm);
+
+ sec = readl(rtc->rtc_base + FTRTC010_RTC_SECOND);
+ min = readl(rtc->rtc_base + FTRTC010_RTC_MINUTE);
+ hour = readl(rtc->rtc_base + FTRTC010_RTC_HOUR);
+ day = readl(rtc->rtc_base + FTRTC010_RTC_DAYS);
+
+ offset = time - (day * 86400 + hour * 3600 + min * 60 + sec);
+
+ writel(offset, rtc->rtc_base + FTRTC010_RTC_RECORD);
+ writel(0x01, rtc->rtc_base + FTRTC010_RTC_CR);
+
+ return 0;
+}
+
+static const struct rtc_class_ops ftrtc010_rtc_ops = {
+ .read_time = ftrtc010_rtc_read_time,
+ .set_time = ftrtc010_rtc_set_time,
+};
+
+static int ftrtc010_rtc_probe(struct platform_device *pdev)
+{
+ u32 days, hour, min, sec;
+ struct ftrtc010_rtc *rtc;
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ int ret;
+
+ rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
+ if (unlikely(!rtc))
+ return -ENOMEM;
+ platform_set_drvdata(pdev, rtc);
+
+ rtc->pclk = devm_clk_get(dev, "PCLK");
+ if (IS_ERR(rtc->pclk)) {
+ dev_err(dev, "could not get PCLK\n");
+ } else {
+ ret = clk_prepare_enable(rtc->pclk);
+ if (ret) {
+ dev_err(dev, "failed to enable PCLK\n");
+ return ret;
+ }
+ }
+ rtc->extclk = devm_clk_get(dev, "EXTCLK");
+ if (IS_ERR(rtc->extclk)) {
+ dev_err(dev, "could not get EXTCLK\n");
+ } else {
+ ret = clk_prepare_enable(rtc->extclk);
+ if (ret) {
+ dev_err(dev, "failed to enable EXTCLK\n");
+ goto err_disable_pclk;
+ }
+ }
+
+ rtc->rtc_irq = platform_get_irq(pdev, 0);
+ if (rtc->rtc_irq < 0) {
+ ret = rtc->rtc_irq;
+ goto err_disable_extclk;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ ret = -ENODEV;
+ goto err_disable_extclk;
+ }
+
+ rtc->rtc_base = devm_ioremap(dev, res->start,
+ resource_size(res));
+ if (!rtc->rtc_base) {
+ ret = -ENOMEM;
+ goto err_disable_extclk;
+ }
+
+ rtc->rtc_dev = devm_rtc_allocate_device(dev);
+ if (IS_ERR(rtc->rtc_dev)) {
+ ret = PTR_ERR(rtc->rtc_dev);
+ goto err_disable_extclk;
+ }
+
+ rtc->rtc_dev->ops = &ftrtc010_rtc_ops;
+
+ sec = readl(rtc->rtc_base + FTRTC010_RTC_SECOND);
+ min = readl(rtc->rtc_base + FTRTC010_RTC_MINUTE);
+ hour = readl(rtc->rtc_base + FTRTC010_RTC_HOUR);
+ days = readl(rtc->rtc_base + FTRTC010_RTC_DAYS);
+
+ rtc->rtc_dev->range_min = (u64)days * 86400 + hour * 3600 +
+ min * 60 + sec;
+ rtc->rtc_dev->range_max = U32_MAX + rtc->rtc_dev->range_min;
+
+ ret = devm_request_irq(dev, rtc->rtc_irq, ftrtc010_rtc_interrupt,
+ IRQF_SHARED, pdev->name, dev);
+ if (unlikely(ret))
+ goto err_disable_extclk;
+
+ return devm_rtc_register_device(rtc->rtc_dev);
+
+err_disable_extclk:
+ clk_disable_unprepare(rtc->extclk);
+err_disable_pclk:
+ clk_disable_unprepare(rtc->pclk);
+ return ret;
+}
+
+static int ftrtc010_rtc_remove(struct platform_device *pdev)
+{
+ struct ftrtc010_rtc *rtc = platform_get_drvdata(pdev);
+
+ if (!IS_ERR(rtc->extclk))
+ clk_disable_unprepare(rtc->extclk);
+ if (!IS_ERR(rtc->pclk))
+ clk_disable_unprepare(rtc->pclk);
+
+ return 0;
+}
+
+static const struct of_device_id ftrtc010_rtc_dt_match[] = {
+ { .compatible = "cortina,gemini-rtc" },
+ { .compatible = "faraday,ftrtc010" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ftrtc010_rtc_dt_match);
+
+static struct platform_driver ftrtc010_rtc_driver = {
+ .driver = {
+ .name = DRV_NAME,
+ .of_match_table = ftrtc010_rtc_dt_match,
+ },
+ .probe = ftrtc010_rtc_probe,
+ .remove = ftrtc010_rtc_remove,
+};
+
+module_platform_driver_probe(ftrtc010_rtc_driver, ftrtc010_rtc_probe);