forked from Minki/linux
0e8431379e
Let the rtc core check the date/time against the RTC range. Reviewed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com> Link: https://lore.kernel.org/r/20191016201414.30934-2-alexandre.belloni@bootlin.com Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
402 lines
9.8 KiB
C
402 lines
9.8 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
// RTC driver for ChromeOS Embedded Controller.
|
|
//
|
|
// Copyright (C) 2017 Google, Inc.
|
|
// Author: Stephen Barber <smbarber@chromium.org>
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/mfd/cros_ec.h>
|
|
#include <linux/module.h>
|
|
#include <linux/platform_data/cros_ec_commands.h>
|
|
#include <linux/platform_data/cros_ec_proto.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/rtc.h>
|
|
#include <linux/slab.h>
|
|
|
|
#define DRV_NAME "cros-ec-rtc"
|
|
|
|
/**
|
|
* struct cros_ec_rtc - Driver data for EC RTC
|
|
*
|
|
* @cros_ec: Pointer to EC device
|
|
* @rtc: Pointer to RTC device
|
|
* @notifier: Notifier info for responding to EC events
|
|
* @saved_alarm: Alarm to restore when interrupts are reenabled
|
|
*/
|
|
struct cros_ec_rtc {
|
|
struct cros_ec_device *cros_ec;
|
|
struct rtc_device *rtc;
|
|
struct notifier_block notifier;
|
|
u32 saved_alarm;
|
|
};
|
|
|
|
static int cros_ec_rtc_get(struct cros_ec_device *cros_ec, u32 command,
|
|
u32 *response)
|
|
{
|
|
int ret;
|
|
struct {
|
|
struct cros_ec_command msg;
|
|
struct ec_response_rtc data;
|
|
} __packed msg;
|
|
|
|
memset(&msg, 0, sizeof(msg));
|
|
msg.msg.command = command;
|
|
msg.msg.insize = sizeof(msg.data);
|
|
|
|
ret = cros_ec_cmd_xfer_status(cros_ec, &msg.msg);
|
|
if (ret < 0) {
|
|
dev_err(cros_ec->dev,
|
|
"error getting %s from EC: %d\n",
|
|
command == EC_CMD_RTC_GET_VALUE ? "time" : "alarm",
|
|
ret);
|
|
return ret;
|
|
}
|
|
|
|
*response = msg.data.time;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int cros_ec_rtc_set(struct cros_ec_device *cros_ec, u32 command,
|
|
u32 param)
|
|
{
|
|
int ret = 0;
|
|
struct {
|
|
struct cros_ec_command msg;
|
|
struct ec_response_rtc data;
|
|
} __packed msg;
|
|
|
|
memset(&msg, 0, sizeof(msg));
|
|
msg.msg.command = command;
|
|
msg.msg.outsize = sizeof(msg.data);
|
|
msg.data.time = param;
|
|
|
|
ret = cros_ec_cmd_xfer_status(cros_ec, &msg.msg);
|
|
if (ret < 0) {
|
|
dev_err(cros_ec->dev, "error setting %s on EC: %d\n",
|
|
command == EC_CMD_RTC_SET_VALUE ? "time" : "alarm",
|
|
ret);
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Read the current time from the EC. */
|
|
static int cros_ec_rtc_read_time(struct device *dev, struct rtc_time *tm)
|
|
{
|
|
struct cros_ec_rtc *cros_ec_rtc = dev_get_drvdata(dev);
|
|
struct cros_ec_device *cros_ec = cros_ec_rtc->cros_ec;
|
|
int ret;
|
|
u32 time;
|
|
|
|
ret = cros_ec_rtc_get(cros_ec, EC_CMD_RTC_GET_VALUE, &time);
|
|
if (ret) {
|
|
dev_err(dev, "error getting time: %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
rtc_time64_to_tm(time, tm);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Set the current EC time. */
|
|
static int cros_ec_rtc_set_time(struct device *dev, struct rtc_time *tm)
|
|
{
|
|
struct cros_ec_rtc *cros_ec_rtc = dev_get_drvdata(dev);
|
|
struct cros_ec_device *cros_ec = cros_ec_rtc->cros_ec;
|
|
int ret;
|
|
time64_t time = rtc_tm_to_time64(tm);
|
|
|
|
ret = cros_ec_rtc_set(cros_ec, EC_CMD_RTC_SET_VALUE, (u32)time);
|
|
if (ret < 0) {
|
|
dev_err(dev, "error setting time: %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Read alarm time from RTC. */
|
|
static int cros_ec_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
|
|
{
|
|
struct cros_ec_rtc *cros_ec_rtc = dev_get_drvdata(dev);
|
|
struct cros_ec_device *cros_ec = cros_ec_rtc->cros_ec;
|
|
int ret;
|
|
u32 current_time, alarm_offset;
|
|
|
|
/*
|
|
* The EC host command for getting the alarm is relative (i.e. 5
|
|
* seconds from now) whereas rtc_wkalrm is absolute. Get the current
|
|
* RTC time first so we can calculate the relative time.
|
|
*/
|
|
ret = cros_ec_rtc_get(cros_ec, EC_CMD_RTC_GET_VALUE, ¤t_time);
|
|
if (ret < 0) {
|
|
dev_err(dev, "error getting time: %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
ret = cros_ec_rtc_get(cros_ec, EC_CMD_RTC_GET_ALARM, &alarm_offset);
|
|
if (ret < 0) {
|
|
dev_err(dev, "error getting alarm: %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
rtc_time64_to_tm(current_time + alarm_offset, &alrm->time);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Set the EC's RTC alarm. */
|
|
static int cros_ec_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
|
|
{
|
|
struct cros_ec_rtc *cros_ec_rtc = dev_get_drvdata(dev);
|
|
struct cros_ec_device *cros_ec = cros_ec_rtc->cros_ec;
|
|
int ret;
|
|
time64_t alarm_time;
|
|
u32 current_time, alarm_offset;
|
|
|
|
/*
|
|
* The EC host command for setting the alarm is relative
|
|
* (i.e. 5 seconds from now) whereas rtc_wkalrm is absolute.
|
|
* Get the current RTC time first so we can calculate the
|
|
* relative time.
|
|
*/
|
|
ret = cros_ec_rtc_get(cros_ec, EC_CMD_RTC_GET_VALUE, ¤t_time);
|
|
if (ret < 0) {
|
|
dev_err(dev, "error getting time: %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
alarm_time = rtc_tm_to_time64(&alrm->time);
|
|
|
|
if (alarm_time < 0 || alarm_time > U32_MAX)
|
|
return -EINVAL;
|
|
|
|
if (!alrm->enabled) {
|
|
/*
|
|
* If the alarm is being disabled, send an alarm
|
|
* clear command.
|
|
*/
|
|
alarm_offset = EC_RTC_ALARM_CLEAR;
|
|
cros_ec_rtc->saved_alarm = (u32)alarm_time;
|
|
} else {
|
|
/* Don't set an alarm in the past. */
|
|
if ((u32)alarm_time <= current_time)
|
|
return -ETIME;
|
|
|
|
alarm_offset = (u32)alarm_time - current_time;
|
|
}
|
|
|
|
ret = cros_ec_rtc_set(cros_ec, EC_CMD_RTC_SET_ALARM, alarm_offset);
|
|
if (ret < 0) {
|
|
dev_err(dev, "error setting alarm: %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int cros_ec_rtc_alarm_irq_enable(struct device *dev,
|
|
unsigned int enabled)
|
|
{
|
|
struct cros_ec_rtc *cros_ec_rtc = dev_get_drvdata(dev);
|
|
struct cros_ec_device *cros_ec = cros_ec_rtc->cros_ec;
|
|
int ret;
|
|
u32 current_time, alarm_offset, alarm_value;
|
|
|
|
ret = cros_ec_rtc_get(cros_ec, EC_CMD_RTC_GET_VALUE, ¤t_time);
|
|
if (ret < 0) {
|
|
dev_err(dev, "error getting time: %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
if (enabled) {
|
|
/* Restore saved alarm if it's still in the future. */
|
|
if (cros_ec_rtc->saved_alarm < current_time)
|
|
alarm_offset = EC_RTC_ALARM_CLEAR;
|
|
else
|
|
alarm_offset = cros_ec_rtc->saved_alarm - current_time;
|
|
|
|
ret = cros_ec_rtc_set(cros_ec, EC_CMD_RTC_SET_ALARM,
|
|
alarm_offset);
|
|
if (ret < 0) {
|
|
dev_err(dev, "error restoring alarm: %d\n", ret);
|
|
return ret;
|
|
}
|
|
} else {
|
|
/* Disable alarm, saving the old alarm value. */
|
|
ret = cros_ec_rtc_get(cros_ec, EC_CMD_RTC_GET_ALARM,
|
|
&alarm_offset);
|
|
if (ret < 0) {
|
|
dev_err(dev, "error saving alarm: %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
alarm_value = current_time + alarm_offset;
|
|
|
|
/*
|
|
* If the current EC alarm is already past, we don't want
|
|
* to set an alarm when we go through the alarm irq enable
|
|
* path.
|
|
*/
|
|
if (alarm_value < current_time)
|
|
cros_ec_rtc->saved_alarm = EC_RTC_ALARM_CLEAR;
|
|
else
|
|
cros_ec_rtc->saved_alarm = alarm_value;
|
|
|
|
alarm_offset = EC_RTC_ALARM_CLEAR;
|
|
ret = cros_ec_rtc_set(cros_ec, EC_CMD_RTC_SET_ALARM,
|
|
alarm_offset);
|
|
if (ret < 0) {
|
|
dev_err(dev, "error disabling alarm: %d\n", ret);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int cros_ec_rtc_event(struct notifier_block *nb,
|
|
unsigned long queued_during_suspend,
|
|
void *_notify)
|
|
{
|
|
struct cros_ec_rtc *cros_ec_rtc;
|
|
struct rtc_device *rtc;
|
|
struct cros_ec_device *cros_ec;
|
|
u32 host_event;
|
|
|
|
cros_ec_rtc = container_of(nb, struct cros_ec_rtc, notifier);
|
|
rtc = cros_ec_rtc->rtc;
|
|
cros_ec = cros_ec_rtc->cros_ec;
|
|
|
|
host_event = cros_ec_get_host_event(cros_ec);
|
|
if (host_event & EC_HOST_EVENT_MASK(EC_HOST_EVENT_RTC)) {
|
|
rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF);
|
|
return NOTIFY_OK;
|
|
} else {
|
|
return NOTIFY_DONE;
|
|
}
|
|
}
|
|
|
|
static const struct rtc_class_ops cros_ec_rtc_ops = {
|
|
.read_time = cros_ec_rtc_read_time,
|
|
.set_time = cros_ec_rtc_set_time,
|
|
.read_alarm = cros_ec_rtc_read_alarm,
|
|
.set_alarm = cros_ec_rtc_set_alarm,
|
|
.alarm_irq_enable = cros_ec_rtc_alarm_irq_enable,
|
|
};
|
|
|
|
#ifdef CONFIG_PM_SLEEP
|
|
static int cros_ec_rtc_suspend(struct device *dev)
|
|
{
|
|
struct platform_device *pdev = to_platform_device(dev);
|
|
struct cros_ec_rtc *cros_ec_rtc = dev_get_drvdata(&pdev->dev);
|
|
|
|
if (device_may_wakeup(dev))
|
|
return enable_irq_wake(cros_ec_rtc->cros_ec->irq);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int cros_ec_rtc_resume(struct device *dev)
|
|
{
|
|
struct platform_device *pdev = to_platform_device(dev);
|
|
struct cros_ec_rtc *cros_ec_rtc = dev_get_drvdata(&pdev->dev);
|
|
|
|
if (device_may_wakeup(dev))
|
|
return disable_irq_wake(cros_ec_rtc->cros_ec->irq);
|
|
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static SIMPLE_DEV_PM_OPS(cros_ec_rtc_pm_ops, cros_ec_rtc_suspend,
|
|
cros_ec_rtc_resume);
|
|
|
|
static int cros_ec_rtc_probe(struct platform_device *pdev)
|
|
{
|
|
struct cros_ec_dev *ec_dev = dev_get_drvdata(pdev->dev.parent);
|
|
struct cros_ec_device *cros_ec = ec_dev->ec_dev;
|
|
struct cros_ec_rtc *cros_ec_rtc;
|
|
struct rtc_time tm;
|
|
int ret;
|
|
|
|
cros_ec_rtc = devm_kzalloc(&pdev->dev, sizeof(*cros_ec_rtc),
|
|
GFP_KERNEL);
|
|
if (!cros_ec_rtc)
|
|
return -ENOMEM;
|
|
|
|
platform_set_drvdata(pdev, cros_ec_rtc);
|
|
cros_ec_rtc->cros_ec = cros_ec;
|
|
|
|
/* Get initial time */
|
|
ret = cros_ec_rtc_read_time(&pdev->dev, &tm);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "failed to read RTC time\n");
|
|
return ret;
|
|
}
|
|
|
|
ret = device_init_wakeup(&pdev->dev, 1);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "failed to initialize wakeup\n");
|
|
return ret;
|
|
}
|
|
|
|
cros_ec_rtc->rtc = devm_rtc_allocate_device(&pdev->dev);
|
|
if (IS_ERR(cros_ec_rtc->rtc))
|
|
return PTR_ERR(cros_ec_rtc->rtc);
|
|
|
|
cros_ec_rtc->rtc->ops = &cros_ec_rtc_ops;
|
|
cros_ec_rtc->rtc->range_max = U32_MAX;
|
|
|
|
ret = rtc_register_device(cros_ec_rtc->rtc);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/* Get RTC events from the EC. */
|
|
cros_ec_rtc->notifier.notifier_call = cros_ec_rtc_event;
|
|
ret = blocking_notifier_chain_register(&cros_ec->event_notifier,
|
|
&cros_ec_rtc->notifier);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "failed to register notifier\n");
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int cros_ec_rtc_remove(struct platform_device *pdev)
|
|
{
|
|
struct cros_ec_rtc *cros_ec_rtc = platform_get_drvdata(pdev);
|
|
struct device *dev = &pdev->dev;
|
|
int ret;
|
|
|
|
ret = blocking_notifier_chain_unregister(
|
|
&cros_ec_rtc->cros_ec->event_notifier,
|
|
&cros_ec_rtc->notifier);
|
|
if (ret) {
|
|
dev_err(dev, "failed to unregister notifier\n");
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver cros_ec_rtc_driver = {
|
|
.probe = cros_ec_rtc_probe,
|
|
.remove = cros_ec_rtc_remove,
|
|
.driver = {
|
|
.name = DRV_NAME,
|
|
.pm = &cros_ec_rtc_pm_ops,
|
|
},
|
|
};
|
|
|
|
module_platform_driver(cros_ec_rtc_driver);
|
|
|
|
MODULE_DESCRIPTION("RTC driver for Chrome OS ECs");
|
|
MODULE_AUTHOR("Stephen Barber <smbarber@chromium.org>");
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_ALIAS("platform:" DRV_NAME);
|