[RFC 2/3] rtc: Add Realtek RTD1295

From: Andreas FÃrber
Date: Sat Aug 19 2017 - 21:37:46 EST


Based on QNAP's mach-rtk119x/driver/rtk_rtc_drv.c code.

Signed-off-by: Andreas FÃrber <afaerber@xxxxxxx>
---
drivers/rtc/Kconfig | 8 +++
drivers/rtc/Makefile | 1 +
drivers/rtc/rtc-rtd119x.c | 175 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 184 insertions(+)
create mode 100644 drivers/rtc/rtc-rtd119x.c

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 72419ac2c52a..882828b1b351 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -1765,6 +1765,14 @@ config RTC_DRV_CPCAP
Say y here for CPCAP rtc found on some Motorola phones
and tablets such as Droid 4.

+config RTC_DRV_RTD119X
+ bool "Realtek RTD129x RTC"
+ depends on ARCH_REALTEK || COMPILE_TEST
+ default ARCH_REALTEK
+ help
+ If you say yes here, you get support for the RTD1295 SoC
+ Real Time Clock.
+
comment "HID Sensor RTC drivers"

config RTC_DRV_HID_SENSOR_TIME
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index acd366b41c85..55a0a5ca45b0 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -131,6 +131,7 @@ obj-$(CONFIG_RTC_DRV_RP5C01) += rtc-rp5c01.o
obj-$(CONFIG_RTC_DRV_RS5C313) += rtc-rs5c313.o
obj-$(CONFIG_RTC_DRV_RS5C348) += rtc-rs5c348.o
obj-$(CONFIG_RTC_DRV_RS5C372) += rtc-rs5c372.o
+obj-$(CONFIG_RTC_DRV_RTD119X) += rtc-rtd119x.o
obj-$(CONFIG_RTC_DRV_RV3029C2) += rtc-rv3029c2.o
obj-$(CONFIG_RTC_DRV_RV8803) += rtc-rv8803.o
obj-$(CONFIG_RTC_DRV_RX4581) += rtc-rx4581.o
diff --git a/drivers/rtc/rtc-rtd119x.c b/drivers/rtc/rtc-rtd119x.c
new file mode 100644
index 000000000000..b532e127b56e
--- /dev/null
+++ b/drivers/rtc/rtc-rtd119x.c
@@ -0,0 +1,175 @@
+/*
+ * Realtek RTD129x RTC
+ *
+ * Copyright (c) 2017 Andreas FÃrber
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+
+#define RTD_RTCSEC 0x00
+#define RTD_RTCMIN 0x04
+#define RTD_RTCHR 0x08
+#define RTD_RTCDATE_LOW 0x0c
+#define RTD_RTCDATE_HIGH 0x10
+#define RTD_RTCACR 0x28
+#define RTD_RTCEN 0x2c
+
+struct rtd119x_rtc {
+ void __iomem *base;
+ struct clk *clk;
+ struct rtc_device *rtcdev;
+ unsigned base_year;
+};
+
+static void rtd119x_rtc_set_enabled(struct device *dev, bool enable)
+{
+ struct rtd119x_rtc *data = dev_get_drvdata(dev);
+ u32 val;
+
+ val = readl_relaxed(data->base + RTD_RTCEN);
+ dev_info(dev, "%s: rtcen = 0x%08x\n", __func__, val);
+ if (enable) {
+ if ((val & 0xff) == 0x5a)
+ return;
+ writel_relaxed(0x5a, data->base + RTD_RTCEN);
+ } else {
+ writel_relaxed(0, data->base + RTD_RTCEN);
+ }
+}
+
+static int rtd119x_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct rtd119x_rtc *data = dev_get_drvdata(dev);
+ time64_t t;
+ u32 day;
+
+ day = readl_relaxed(data->base + RTD_RTCDATE_LOW);
+ day |= readl_relaxed(data->base + RTD_RTCDATE_HIGH) << 8;
+ t = mktime64(data->base_year, 1, 1, 0, 0, 0);
+ t += day * 24 * 60 * 60;
+ rtc_time64_to_tm(t, tm);
+ tm->tm_sec = readl_relaxed(data->base + RTD_RTCSEC) >> 1;
+ tm->tm_min = readl_relaxed(data->base + RTD_RTCMIN);
+ tm->tm_hour = readl_relaxed(data->base + RTD_RTCHR);
+
+ return rtc_valid_tm(tm);
+}
+
+static int rtd119x_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct rtd119x_rtc *data = dev_get_drvdata(dev);
+ time64_t time_base, new_time, time_delta;
+ unsigned long day;
+
+ if (tm->tm_year < data->base_year)
+ return -EINVAL;
+
+ time_base = mktime64(data->base_year, 1, 1, 0, 0, 0);
+ new_time = rtc_tm_to_time64(tm);
+ time_delta = new_time - time_base;
+ day = time_delta / (24 * 60 * 60);
+ if (day > 0x7fff)
+ return -EINVAL;
+
+ rtd119x_rtc_set_enabled(dev, false);
+
+ writel_relaxed(tm->tm_sec, data->base + RTD_RTCSEC);
+ writel_relaxed(tm->tm_min, data->base + RTD_RTCMIN);
+ writel_relaxed(tm->tm_hour, data->base + RTD_RTCHR);
+ writel_relaxed(day & 0xff, data->base + RTD_RTCDATE_LOW);
+ writel_relaxed((day >> 8) & 0x7f, data->base + RTD_RTCDATE_HIGH);
+
+ rtd119x_rtc_set_enabled(dev, true);
+
+ return 0;
+}
+
+static int rtd119x_rtc_open(struct device *dev)
+{
+ struct rtd119x_rtc *data = dev_get_drvdata(dev);
+ u32 val;
+ int ret;
+
+ ret = clk_prepare_enable(data->clk);
+ if (ret)
+ return ret;
+
+ val = readl_relaxed(data->base + RTD_RTCACR);
+ dev_info(dev, "rtcacr = 0x%08x\n", val);
+ if (!(val & BIT(7))) {
+ }
+
+ rtd119x_rtc_set_enabled(dev, true);
+
+ return 0;
+}
+
+static void rtd119x_rtc_release(struct device *dev)
+{
+ struct rtd119x_rtc *data = dev_get_drvdata(dev);
+
+ rtd119x_rtc_set_enabled(dev, false);
+
+ clk_disable_unprepare(data->clk);
+}
+
+static const struct rtc_class_ops rtd119x_rtc_ops = {
+ .open = rtd119x_rtc_open,
+ .release = rtd119x_rtc_release,
+ .read_time = rtd119x_rtc_read_time,
+ .set_time = rtd119x_rtc_set_time,
+};
+
+static const struct of_device_id rtd119x_rtc_dt_ids[] = {
+ { .compatible = "realtek,rtd1295-rtc" },
+ { }
+};
+
+static int rtd119x_rtc_probe(struct platform_device *pdev)
+{
+ struct rtd119x_rtc *data;
+ struct resource *res;
+
+ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, data);
+ data->base_year = 2014;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ data->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(data->base))
+ return PTR_ERR(data->base);
+
+ data->clk = of_clk_get(pdev->dev.of_node, 0);
+ if (IS_ERR(data->clk))
+ return PTR_ERR(data->clk);
+
+ data->rtcdev = devm_rtc_device_register(&pdev->dev, "rtc",
+ &rtd119x_rtc_ops, THIS_MODULE);
+ if (IS_ERR(data->rtcdev)) {
+ dev_err(&pdev->dev, "failed to register rtc device");
+ clk_put(data->clk);
+ return PTR_ERR(data->rtcdev);
+ }
+
+ return 0;
+}
+
+static struct platform_driver rtd119x_rtc_driver = {
+ .probe = rtd119x_rtc_probe,
+ .driver = {
+ .name = "rtd1295-rtc",
+ .of_match_table = rtd119x_rtc_dt_ids,
+ },
+};
+builtin_platform_driver(rtd119x_rtc_driver);
--
2.12.3