MLK-14695-3 rtc: add imx sc rtc driver

Add i.MX system controller RTC driver. The RTC
is controlled by system controller, and kernel RTC
driver needs to communicate with system controller
via SC firmware API.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>

3 files changed, 227 insertions, 0 deletions

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 0723c97ebea3..e209dc80a07a 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -1647,6 +1647,13 @@ config RTC_DRV_SNVS
 	   This driver can also be built as a module, if so, the module
 	   will be called "rtc-snvs".
 
+config RTC_DRV_IMX_SC
+	tristate "NXP SC RTC support"
+	depends on OF
+	help
+	   If you say yes here you get support for the NXP SC
+	   RTC module.
+
 config RTC_DRV_SIRFSOC
 	tristate "SiRFSOC RTC"
 	depends on ARCH_SIRF
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index 1ac694a330c8..e68cc1c791fa 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -141,6 +141,7 @@ obj-$(CONFIG_RTC_DRV_SA1100)	+= rtc-sa1100.o
 obj-$(CONFIG_RTC_DRV_SH)	+= rtc-sh.o
 obj-$(CONFIG_RTC_DRV_SIRFSOC)	+= rtc-sirfsoc.o
 obj-$(CONFIG_RTC_DRV_SNVS)	+= rtc-snvs.o
+obj-$(CONFIG_RTC_DRV_IMX_SC)	+= rtc-imx-sc.o
 obj-$(CONFIG_RTC_DRV_SPEAR)	+= rtc-spear.o
 obj-$(CONFIG_RTC_DRV_STARFIRE)	+= rtc-starfire.o
 obj-$(CONFIG_RTC_DRV_STK17TA8)	+= rtc-stk17ta8.o
diff --git a/drivers/rtc/rtc-imx-sc.c b/drivers/rtc/rtc-imx-sc.c
new file mode 100644
index 000000000000..ce3add9dbddd
--- /dev/null
+++ b/drivers/rtc/rtc-imx-sc.c
@@ -0,0 +1,219 @@
+/*
+ * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ * Copyright 2017 NXP
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <soc/imx8/sc/sci.h>
+
+sc_ipc_t timer_ipcHandle;
+
+struct imx_sc_rtc_data {
+	struct rtc_device *rtc;
+	spinlock_t lock;
+};
+
+struct imx_sc_rtc_data *data;
+
+static int imx_sc_rtc_alarm_sc_notify(struct notifier_block *nb, unsigned long event, void *dummy)
+{
+	u32 events = 0;
+
+	rtc_update_irq(data->rtc, 1, events);
+
+	return 0;
+}
+
+static struct notifier_block imx_sc_rtc_alarm_sc_notifier = {
+	.notifier_call = imx_sc_rtc_alarm_sc_notify,
+};
+
+static int imx_sc_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+	u32 time = 0;
+	sc_err_t sciErr = SC_ERR_NONE;
+
+	if (!timer_ipcHandle)
+		return -ENODEV;
+
+	sciErr = sc_timer_get_rtc_sec1970(timer_ipcHandle, &time);
+	if (sciErr) {
+		dev_err(dev, "failed to read time: %d\n", sciErr);
+		return -EINVAL;
+	}
+
+	rtc_time_to_tm(time, tm);
+
+	return 0;
+}
+
+static int imx_sc_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+	sc_err_t sciErr = SC_ERR_NONE;
+
+	if (!timer_ipcHandle)
+		return -ENODEV;
+
+	sciErr = sc_timer_set_rtc_time(timer_ipcHandle,
+		tm->tm_year + 1900,
+		tm->tm_mon + 1,
+		tm->tm_mday,
+		tm->tm_hour,
+		tm->tm_min,
+		tm->tm_sec);
+
+	if (sciErr) {
+		dev_err(dev, "failed to set time: %d\n", sciErr);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int imx_sc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	return 0;
+}
+
+static int imx_sc_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
+{
+	return 0;
+}
+
+static int imx_sc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	sc_err_t sciErr = SC_ERR_NONE;
+	struct rtc_time *alrm_tm = &alrm->time;
+
+	if (!timer_ipcHandle)
+		return -ENODEV;
+
+	sciErr = sc_timer_set_rtc_alarm(timer_ipcHandle,
+		alrm_tm->tm_year + 1900,
+		alrm_tm->tm_mon + 1,
+		alrm_tm->tm_mday,
+		alrm_tm->tm_hour,
+		alrm_tm->tm_min,
+		alrm_tm->tm_sec);
+
+	return 0;
+}
+
+static const struct rtc_class_ops imx_sc_rtc_ops = {
+	.read_time = imx_sc_rtc_read_time,
+	.set_time = imx_sc_rtc_set_time,
+	.read_alarm = imx_sc_rtc_read_alarm,
+	.set_alarm = imx_sc_rtc_set_alarm,
+	.alarm_irq_enable = imx_sc_rtc_alarm_irq_enable,
+};
+
+static int imx_sc_rtc_probe(struct platform_device *pdev)
+{
+	int ret = 0;
+	uint32_t mu_id;
+	sc_err_t sciErr;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, data);
+
+	device_init_wakeup(&pdev->dev, true);
+	data->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
+					&imx_sc_rtc_ops, THIS_MODULE);
+	if (IS_ERR(data->rtc)) {
+		ret = PTR_ERR(data->rtc);
+		dev_err(&pdev->dev, "failed to register rtc: %d\n", ret);
+		goto error_rtc_device_register;
+	}
+
+	sciErr = sc_ipc_getMuID(&mu_id);
+	if (sciErr != SC_ERR_NONE) {
+		dev_err(&pdev->dev, "can not obtain mu id: %d\n", sciErr);
+		return sciErr;
+	}
+
+	sciErr = sc_ipc_open(&timer_ipcHandle, mu_id);
+
+	if (sciErr != SC_ERR_NONE) {
+		dev_err(&pdev->dev, "can not open mu channel to scu: %d\n", sciErr);
+		return sciErr;
+	};
+
+	register_scu_notifier(&imx_sc_rtc_alarm_sc_notifier);
+
+error_rtc_device_register:
+
+	return ret;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int imx_sc_rtc_suspend(struct device *dev)
+{
+	return 0;
+}
+
+static int imx_sc_rtc_suspend_noirq(struct device *dev)
+{
+	return 0;
+}
+
+static int imx_sc_rtc_resume(struct device *dev)
+{
+	return 0;
+}
+
+static int imx_sc_rtc_resume_noirq(struct device *dev)
+{
+	return 0;
+}
+
+static const struct dev_pm_ops imx_sc_rtc_pm_ops = {
+	.suspend = imx_sc_rtc_suspend,
+	.suspend_noirq = imx_sc_rtc_suspend_noirq,
+	.resume = imx_sc_rtc_resume,
+	.resume_noirq = imx_sc_rtc_resume_noirq,
+};
+
+#define IMX_SC_RTC_PM_OPS	(&imx_sc_rtc_pm_ops)
+
+#else
+
+#define IMX8_SC_RTC_PM_OPS	NULL
+
+#endif
+
+static const struct of_device_id imx_sc_dt_ids[] = {
+	{ .compatible = "fsl,imx-sc-rtc", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx_sc_dt_ids);
+
+static struct platform_driver imx_sc_rtc_driver = {
+	.driver = {
+		.name	= "imx_sc_rtc",
+		.pm	= IMX_SC_RTC_PM_OPS,
+		.of_match_table = imx_sc_dt_ids,
+	},
+	.probe		= imx_sc_rtc_probe,
+};
+module_platform_driver(imx_sc_rtc_driver);
+
+MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
+MODULE_DESCRIPTION("NXP i.MX SC RTC Driver");
+MODULE_LICENSE("GPL");