linux-stable/drivers/rtc/rtc-mpc5121.c
Uwe Kleine-König 22edbc10a5 rtc: mpc5121: Convert to platform remove callback returning void
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230304133028.2135435-18-u.kleine-koenig@pengutronix.de
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2023-03-17 23:03:17 +01:00

409 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Real-time clock driver for MPC5121
*
* Copyright 2007, Domen Puncer <domen.puncer@telargo.com>
* Copyright 2008, Freescale Semiconductor, Inc. All rights reserved.
* Copyright 2011, Dmitry Eremin-Solenikov
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/rtc.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/io.h>
#include <linux/slab.h>
struct mpc5121_rtc_regs {
u8 set_time; /* RTC + 0x00 */
u8 hour_set; /* RTC + 0x01 */
u8 minute_set; /* RTC + 0x02 */
u8 second_set; /* RTC + 0x03 */
u8 set_date; /* RTC + 0x04 */
u8 month_set; /* RTC + 0x05 */
u8 weekday_set; /* RTC + 0x06 */
u8 date_set; /* RTC + 0x07 */
u8 write_sw; /* RTC + 0x08 */
u8 sw_set; /* RTC + 0x09 */
u16 year_set; /* RTC + 0x0a */
u8 alm_enable; /* RTC + 0x0c */
u8 alm_hour_set; /* RTC + 0x0d */
u8 alm_min_set; /* RTC + 0x0e */
u8 int_enable; /* RTC + 0x0f */
u8 reserved1;
u8 hour; /* RTC + 0x11 */
u8 minute; /* RTC + 0x12 */
u8 second; /* RTC + 0x13 */
u8 month; /* RTC + 0x14 */
u8 wday_mday; /* RTC + 0x15 */
u16 year; /* RTC + 0x16 */
u8 int_alm; /* RTC + 0x18 */
u8 int_sw; /* RTC + 0x19 */
u8 alm_status; /* RTC + 0x1a */
u8 sw_minute; /* RTC + 0x1b */
u8 bus_error_1; /* RTC + 0x1c */
u8 int_day; /* RTC + 0x1d */
u8 int_min; /* RTC + 0x1e */
u8 int_sec; /* RTC + 0x1f */
/*
* target_time:
* intended to be used for hibernation but hibernation
* does not work on silicon rev 1.5 so use it for non-volatile
* storage of offset between the actual_time register and linux
* time
*/
u32 target_time; /* RTC + 0x20 */
/*
* actual_time:
* readonly time since VBAT_RTC was last connected
*/
u32 actual_time; /* RTC + 0x24 */
u32 keep_alive; /* RTC + 0x28 */
};
struct mpc5121_rtc_data {
unsigned irq;
unsigned irq_periodic;
struct mpc5121_rtc_regs __iomem *regs;
struct rtc_device *rtc;
struct rtc_wkalrm wkalarm;
};
/*
* Update second/minute/hour registers.
*
* This is just so alarm will work.
*/
static void mpc5121_rtc_update_smh(struct mpc5121_rtc_regs __iomem *regs,
struct rtc_time *tm)
{
out_8(&regs->second_set, tm->tm_sec);
out_8(&regs->minute_set, tm->tm_min);
out_8(&regs->hour_set, tm->tm_hour);
/* set time sequence */
out_8(&regs->set_time, 0x1);
out_8(&regs->set_time, 0x3);
out_8(&regs->set_time, 0x1);
out_8(&regs->set_time, 0x0);
}
static int mpc5121_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);
struct mpc5121_rtc_regs __iomem *regs = rtc->regs;
unsigned long now;
/*
* linux time is actual_time plus the offset saved in target_time
*/
now = in_be32(&regs->actual_time) + in_be32(&regs->target_time);
rtc_time64_to_tm(now, tm);
/*
* update second minute hour registers
* so alarms will work
*/
mpc5121_rtc_update_smh(regs, tm);
return 0;
}
static int mpc5121_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);
struct mpc5121_rtc_regs __iomem *regs = rtc->regs;
unsigned long now;
/*
* The actual_time register is read only so we write the offset
* between it and linux time to the target_time register.
*/
now = rtc_tm_to_time64(tm);
out_be32(&regs->target_time, now - in_be32(&regs->actual_time));
/*
* update second minute hour registers
* so alarms will work
*/
mpc5121_rtc_update_smh(regs, tm);
return 0;
}
static int mpc5200_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);
struct mpc5121_rtc_regs __iomem *regs = rtc->regs;
int tmp;
tm->tm_sec = in_8(&regs->second);
tm->tm_min = in_8(&regs->minute);
/* 12 hour format? */
if (in_8(&regs->hour) & 0x20)
tm->tm_hour = (in_8(&regs->hour) >> 1) +
(in_8(&regs->hour) & 1 ? 12 : 0);
else
tm->tm_hour = in_8(&regs->hour);
tmp = in_8(&regs->wday_mday);
tm->tm_mday = tmp & 0x1f;
tm->tm_mon = in_8(&regs->month) - 1;
tm->tm_year = in_be16(&regs->year) - 1900;
tm->tm_wday = (tmp >> 5) % 7;
tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
tm->tm_isdst = 0;
return 0;
}
static int mpc5200_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);
struct mpc5121_rtc_regs __iomem *regs = rtc->regs;
mpc5121_rtc_update_smh(regs, tm);
/* date */
out_8(&regs->month_set, tm->tm_mon + 1);
out_8(&regs->weekday_set, tm->tm_wday ? tm->tm_wday : 7);
out_8(&regs->date_set, tm->tm_mday);
out_be16(&regs->year_set, tm->tm_year + 1900);
/* set date sequence */
out_8(&regs->set_date, 0x1);
out_8(&regs->set_date, 0x3);
out_8(&regs->set_date, 0x1);
out_8(&regs->set_date, 0x0);
return 0;
}
static int mpc5121_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);
struct mpc5121_rtc_regs __iomem *regs = rtc->regs;
*alarm = rtc->wkalarm;
alarm->pending = in_8(&regs->alm_status);
return 0;
}
static int mpc5121_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);
struct mpc5121_rtc_regs __iomem *regs = rtc->regs;
alarm->time.tm_mday = -1;
alarm->time.tm_mon = -1;
alarm->time.tm_year = -1;
out_8(&regs->alm_min_set, alarm->time.tm_min);
out_8(&regs->alm_hour_set, alarm->time.tm_hour);
out_8(&regs->alm_enable, alarm->enabled);
rtc->wkalarm = *alarm;
return 0;
}
static irqreturn_t mpc5121_rtc_handler(int irq, void *dev)
{
struct mpc5121_rtc_data *rtc = dev_get_drvdata((struct device *)dev);
struct mpc5121_rtc_regs __iomem *regs = rtc->regs;
if (in_8(&regs->int_alm)) {
/* acknowledge and clear status */
out_8(&regs->int_alm, 1);
out_8(&regs->alm_status, 1);
rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);
return IRQ_HANDLED;
}
return IRQ_NONE;
}
static irqreturn_t mpc5121_rtc_handler_upd(int irq, void *dev)
{
struct mpc5121_rtc_data *rtc = dev_get_drvdata((struct device *)dev);
struct mpc5121_rtc_regs __iomem *regs = rtc->regs;
if (in_8(&regs->int_sec) && (in_8(&regs->int_enable) & 0x1)) {
/* acknowledge */
out_8(&regs->int_sec, 1);
rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_UF);
return IRQ_HANDLED;
}
return IRQ_NONE;
}
static int mpc5121_rtc_alarm_irq_enable(struct device *dev,
unsigned int enabled)
{
struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);
struct mpc5121_rtc_regs __iomem *regs = rtc->regs;
int val;
if (enabled)
val = 1;
else
val = 0;
out_8(&regs->alm_enable, val);
rtc->wkalarm.enabled = val;
return 0;
}
static const struct rtc_class_ops mpc5121_rtc_ops = {
.read_time = mpc5121_rtc_read_time,
.set_time = mpc5121_rtc_set_time,
.read_alarm = mpc5121_rtc_read_alarm,
.set_alarm = mpc5121_rtc_set_alarm,
.alarm_irq_enable = mpc5121_rtc_alarm_irq_enable,
};
static const struct rtc_class_ops mpc5200_rtc_ops = {
.read_time = mpc5200_rtc_read_time,
.set_time = mpc5200_rtc_set_time,
.read_alarm = mpc5121_rtc_read_alarm,
.set_alarm = mpc5121_rtc_set_alarm,
.alarm_irq_enable = mpc5121_rtc_alarm_irq_enable,
};
static int mpc5121_rtc_probe(struct platform_device *op)
{
struct mpc5121_rtc_data *rtc;
int err = 0;
rtc = devm_kzalloc(&op->dev, sizeof(*rtc), GFP_KERNEL);
if (!rtc)
return -ENOMEM;
rtc->regs = devm_platform_ioremap_resource(op, 0);
if (IS_ERR(rtc->regs)) {
dev_err(&op->dev, "%s: couldn't map io space\n", __func__);
return PTR_ERR(rtc->regs);
}
device_init_wakeup(&op->dev, 1);
platform_set_drvdata(op, rtc);
rtc->irq = irq_of_parse_and_map(op->dev.of_node, 1);
err = devm_request_irq(&op->dev, rtc->irq, mpc5121_rtc_handler, 0,
"mpc5121-rtc", &op->dev);
if (err) {
dev_err(&op->dev, "%s: could not request irq: %i\n",
__func__, rtc->irq);
goto out_dispose;
}
rtc->irq_periodic = irq_of_parse_and_map(op->dev.of_node, 0);
err = devm_request_irq(&op->dev, rtc->irq_periodic,
mpc5121_rtc_handler_upd, 0, "mpc5121-rtc_upd",
&op->dev);
if (err) {
dev_err(&op->dev, "%s: could not request irq: %i\n",
__func__, rtc->irq_periodic);
goto out_dispose2;
}
rtc->rtc = devm_rtc_allocate_device(&op->dev);
if (IS_ERR(rtc->rtc)) {
err = PTR_ERR(rtc->rtc);
goto out_dispose2;
}
rtc->rtc->ops = &mpc5200_rtc_ops;
set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->rtc->features);
clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->rtc->features);
rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_0000;
rtc->rtc->range_max = 65733206399ULL; /* 4052-12-31 23:59:59 */
if (of_device_is_compatible(op->dev.of_node, "fsl,mpc5121-rtc")) {
u32 ka;
ka = in_be32(&rtc->regs->keep_alive);
if (ka & 0x02) {
dev_warn(&op->dev,
"mpc5121-rtc: Battery or oscillator failure!\n");
out_be32(&rtc->regs->keep_alive, ka);
}
rtc->rtc->ops = &mpc5121_rtc_ops;
/*
* This is a limitation of the driver that abuses the target
* time register, the actual maximum year for the mpc5121 is
* also 4052.
*/
rtc->rtc->range_min = 0;
rtc->rtc->range_max = U32_MAX;
}
err = devm_rtc_register_device(rtc->rtc);
if (err)
goto out_dispose2;
return 0;
out_dispose2:
irq_dispose_mapping(rtc->irq_periodic);
out_dispose:
irq_dispose_mapping(rtc->irq);
return err;
}
static void mpc5121_rtc_remove(struct platform_device *op)
{
struct mpc5121_rtc_data *rtc = platform_get_drvdata(op);
struct mpc5121_rtc_regs __iomem *regs = rtc->regs;
/* disable interrupt, so there are no nasty surprises */
out_8(&regs->alm_enable, 0);
out_8(&regs->int_enable, in_8(&regs->int_enable) & ~0x1);
irq_dispose_mapping(rtc->irq);
irq_dispose_mapping(rtc->irq_periodic);
}
#ifdef CONFIG_OF
static const struct of_device_id mpc5121_rtc_match[] = {
{ .compatible = "fsl,mpc5121-rtc", },
{ .compatible = "fsl,mpc5200-rtc", },
{},
};
MODULE_DEVICE_TABLE(of, mpc5121_rtc_match);
#endif
static struct platform_driver mpc5121_rtc_driver = {
.driver = {
.name = "mpc5121-rtc",
.of_match_table = of_match_ptr(mpc5121_rtc_match),
},
.probe = mpc5121_rtc_probe,
.remove_new = mpc5121_rtc_remove,
};
module_platform_driver(mpc5121_rtc_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("John Rigby <jcrigby@gmail.com>");