Commit 6ef35398 authored by Neil Armstrong's avatar Neil Armstrong Committed by Alexandre Belloni

rtc: Add Amlogic Virtual Wake RTC

The Amlogic Meson GX SoCs uses a special register to store the
time in seconds to wakeup after a system suspend.

In order to be able to reuse the RTC wakealarm feature, this
driver implements a fake RTC device which uses the system time
to deduce a suspend delay.
Signed-off-by: default avatarNeil Armstrong <narmstrong@baylibre.com>
[khilman: rebase to v5.3-rc, rework and modernization]
Signed-off-by: default avatarKevin Hilman <khilman@baylibre.com>
Link: https://lore.kernel.org/r/20190812232850.8016-3-khilman@kernel.orgSigned-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
parent ed162396
...@@ -1443,6 +1443,7 @@ F: arch/arm64/boot/dts/amlogic/ ...@@ -1443,6 +1443,7 @@ F: arch/arm64/boot/dts/amlogic/
F: drivers/pinctrl/meson/ F: drivers/pinctrl/meson/
F: drivers/mmc/host/meson* F: drivers/mmc/host/meson*
F: drivers/soc/amlogic/ F: drivers/soc/amlogic/
F: drivers/rtc/rtc-meson*
N: meson N: meson
ARM/Amlogic Meson SoC Sound Drivers ARM/Amlogic Meson SoC Sound Drivers
......
...@@ -373,6 +373,17 @@ config RTC_DRV_MAX77686 ...@@ -373,6 +373,17 @@ config RTC_DRV_MAX77686
This driver can also be built as a module. If so, the module This driver can also be built as a module. If so, the module
will be called rtc-max77686. will be called rtc-max77686.
config RTC_DRV_MESON_VRTC
tristate "Amlogic Meson Virtual RTC"
depends on ARCH_MESON || COMPILE_TEST
default m if ARCH_MESON
help
If you say yes here you will get support for the
Virtual RTC of Amlogic SoCs.
This driver can also be built as a module. If so, the module
will be called rtc-meson-vrtc.
config RTC_DRV_RK808 config RTC_DRV_RK808
tristate "Rockchip RK805/RK808/RK809/RK817/RK818 RTC" tristate "Rockchip RK805/RK808/RK809/RK817/RK818 RTC"
depends on MFD_RK808 depends on MFD_RK808
......
...@@ -102,6 +102,7 @@ obj-$(CONFIG_RTC_DRV_MAX8907) += rtc-max8907.o ...@@ -102,6 +102,7 @@ obj-$(CONFIG_RTC_DRV_MAX8907) += rtc-max8907.o
obj-$(CONFIG_RTC_DRV_MAX8925) += rtc-max8925.o obj-$(CONFIG_RTC_DRV_MAX8925) += rtc-max8925.o
obj-$(CONFIG_RTC_DRV_MAX8997) += rtc-max8997.o obj-$(CONFIG_RTC_DRV_MAX8997) += rtc-max8997.o
obj-$(CONFIG_RTC_DRV_MAX8998) += rtc-max8998.o obj-$(CONFIG_RTC_DRV_MAX8998) += rtc-max8998.o
obj-$(CONFIG_RTC_DRV_MESON_VRTC)+= rtc-meson-vrtc.o
obj-$(CONFIG_RTC_DRV_MC13XXX) += rtc-mc13xxx.o obj-$(CONFIG_RTC_DRV_MC13XXX) += rtc-mc13xxx.o
obj-$(CONFIG_RTC_DRV_MCP795) += rtc-mcp795.o obj-$(CONFIG_RTC_DRV_MCP795) += rtc-mcp795.o
obj-$(CONFIG_RTC_DRV_MESON) += rtc-meson.o obj-$(CONFIG_RTC_DRV_MESON) += rtc-meson.o
......
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2019 BayLibre, SAS
* Author: Neil Armstrong <narmstrong@baylibre.com>
* Copyright (C) 2015 Amlogic, Inc. All rights reserved.
*/
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/time64.h>
struct meson_vrtc_data {
void __iomem *io_alarm;
struct rtc_device *rtc;
unsigned long alarm_time;
bool enabled;
};
static int meson_vrtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct timespec64 time;
dev_dbg(dev, "%s\n", __func__);
ktime_get_raw_ts64(&time);
rtc_time64_to_tm(time.tv_sec, tm);
return 0;
}
static void meson_vrtc_set_wakeup_time(struct meson_vrtc_data *vrtc,
unsigned long time)
{
writel_relaxed(time, vrtc->io_alarm);
}
static int meson_vrtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);
dev_dbg(dev, "%s: alarm->enabled=%d\n", __func__, alarm->enabled);
if (alarm->enabled)
vrtc->alarm_time = rtc_tm_to_time64(&alarm->time);
else
vrtc->alarm_time = 0;
return 0;
}
static int meson_vrtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);
vrtc->enabled = enabled;
return 0;
}
static const struct rtc_class_ops meson_vrtc_ops = {
.read_time = meson_vrtc_read_time,
.set_alarm = meson_vrtc_set_alarm,
.alarm_irq_enable = meson_vrtc_alarm_irq_enable,
};
static int meson_vrtc_probe(struct platform_device *pdev)
{
struct meson_vrtc_data *vrtc;
int ret;
vrtc = devm_kzalloc(&pdev->dev, sizeof(*vrtc), GFP_KERNEL);
if (!vrtc)
return -ENOMEM;
vrtc->io_alarm = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(vrtc->io_alarm))
return PTR_ERR(vrtc->io_alarm);
device_init_wakeup(&pdev->dev, 1);
platform_set_drvdata(pdev, vrtc);
vrtc->rtc = devm_rtc_allocate_device(&pdev->dev);
if (IS_ERR(vrtc->rtc))
return PTR_ERR(vrtc->rtc);
vrtc->rtc->ops = &meson_vrtc_ops;
ret = rtc_register_device(vrtc->rtc);
if (ret)
return ret;
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int meson_vrtc_suspend(struct device *dev)
{
struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);
dev_dbg(dev, "%s\n", __func__);
if (vrtc->alarm_time) {
unsigned long local_time;
long alarm_secs;
struct timespec64 time;
ktime_get_raw_ts64(&time);
local_time = time.tv_sec;
dev_dbg(dev, "alarm_time = %lus, local_time=%lus\n",
vrtc->alarm_time, local_time);
alarm_secs = vrtc->alarm_time - local_time;
if (alarm_secs > 0) {
meson_vrtc_set_wakeup_time(vrtc, alarm_secs);
dev_dbg(dev, "system will wakeup in %lds.\n",
alarm_secs);
} else {
dev_err(dev, "alarm time already passed: %lds.\n",
alarm_secs);
}
}
return 0;
}
static int meson_vrtc_resume(struct device *dev)
{
struct meson_vrtc_data *vrtc = dev_get_drvdata(dev);
dev_dbg(dev, "%s\n", __func__);
vrtc->alarm_time = 0;
meson_vrtc_set_wakeup_time(vrtc, 0);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(meson_vrtc_pm_ops,
meson_vrtc_suspend, meson_vrtc_resume);
static const struct of_device_id meson_vrtc_dt_match[] = {
{ .compatible = "amlogic,meson-vrtc"},
{},
};
MODULE_DEVICE_TABLE(of, meson_vrtc_dt_match);
static struct platform_driver meson_vrtc_driver = {
.probe = meson_vrtc_probe,
.driver = {
.name = "meson-vrtc",
.of_match_table = meson_vrtc_dt_match,
.pm = &meson_vrtc_pm_ops,
},
};
module_platform_driver(meson_vrtc_driver);
MODULE_DESCRIPTION("Amlogic Virtual Wakeup RTC Timer driver");
MODULE_LICENSE("GPL");
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