linux-stable/drivers/rtc/rtc-asm9260.c
Uwe Kleine-König ad01bf83bf rtc: asm9260: 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/20230304133028.2135435-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2023-03-17 23:03:17 +01:00

339 lines
8.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2016 Oleksij Rempel <linux@rempel-privat.de>
*/
#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
/* Miscellaneous registers */
/* Interrupt Location Register */
#define HW_ILR 0x00
#define BM_RTCALF BIT(1)
#define BM_RTCCIF BIT(0)
/* Clock Control Register */
#define HW_CCR 0x08
/* Calibration counter disable */
#define BM_CCALOFF BIT(4)
/* Reset internal oscillator divider */
#define BM_CTCRST BIT(1)
/* Clock Enable */
#define BM_CLKEN BIT(0)
/* Counter Increment Interrupt Register */
#define HW_CIIR 0x0C
#define BM_CIIR_IMYEAR BIT(7)
#define BM_CIIR_IMMON BIT(6)
#define BM_CIIR_IMDOY BIT(5)
#define BM_CIIR_IMDOW BIT(4)
#define BM_CIIR_IMDOM BIT(3)
#define BM_CIIR_IMHOUR BIT(2)
#define BM_CIIR_IMMIN BIT(1)
#define BM_CIIR_IMSEC BIT(0)
/* Alarm Mask Register */
#define HW_AMR 0x10
#define BM_AMR_IMYEAR BIT(7)
#define BM_AMR_IMMON BIT(6)
#define BM_AMR_IMDOY BIT(5)
#define BM_AMR_IMDOW BIT(4)
#define BM_AMR_IMDOM BIT(3)
#define BM_AMR_IMHOUR BIT(2)
#define BM_AMR_IMMIN BIT(1)
#define BM_AMR_IMSEC BIT(0)
#define BM_AMR_OFF 0xff
/* Consolidated time registers */
#define HW_CTIME0 0x14
#define BM_CTIME0_DOW_S 24
#define BM_CTIME0_DOW_M 0x7
#define BM_CTIME0_HOUR_S 16
#define BM_CTIME0_HOUR_M 0x1f
#define BM_CTIME0_MIN_S 8
#define BM_CTIME0_MIN_M 0x3f
#define BM_CTIME0_SEC_S 0
#define BM_CTIME0_SEC_M 0x3f
#define HW_CTIME1 0x18
#define BM_CTIME1_YEAR_S 16
#define BM_CTIME1_YEAR_M 0xfff
#define BM_CTIME1_MON_S 8
#define BM_CTIME1_MON_M 0xf
#define BM_CTIME1_DOM_S 0
#define BM_CTIME1_DOM_M 0x1f
#define HW_CTIME2 0x1C
#define BM_CTIME2_DOY_S 0
#define BM_CTIME2_DOY_M 0xfff
/* Time counter registers */
#define HW_SEC 0x20
#define HW_MIN 0x24
#define HW_HOUR 0x28
#define HW_DOM 0x2C
#define HW_DOW 0x30
#define HW_DOY 0x34
#define HW_MONTH 0x38
#define HW_YEAR 0x3C
#define HW_CALIBRATION 0x40
#define BM_CALDIR_BACK BIT(17)
#define BM_CALVAL_M 0x1ffff
/* General purpose registers */
#define HW_GPREG0 0x44
#define HW_GPREG1 0x48
#define HW_GPREG2 0x4C
#define HW_GPREG3 0x50
#define HW_GPREG4 0x54
/* Alarm register group */
#define HW_ALSEC 0x60
#define HW_ALMIN 0x64
#define HW_ALHOUR 0x68
#define HW_ALDOM 0x6C
#define HW_ALDOW 0x70
#define HW_ALDOY 0x74
#define HW_ALMON 0x78
#define HW_ALYEAR 0x7C
struct asm9260_rtc_priv {
struct device *dev;
void __iomem *iobase;
struct rtc_device *rtc;
struct clk *clk;
};
static irqreturn_t asm9260_rtc_irq(int irq, void *dev_id)
{
struct asm9260_rtc_priv *priv = dev_id;
u32 isr;
unsigned long events = 0;
rtc_lock(priv->rtc);
isr = ioread32(priv->iobase + HW_CIIR);
if (!isr) {
rtc_unlock(priv->rtc);
return IRQ_NONE;
}
iowrite32(0, priv->iobase + HW_CIIR);
rtc_unlock(priv->rtc);
events |= RTC_AF | RTC_IRQF;
rtc_update_irq(priv->rtc, 1, events);
return IRQ_HANDLED;
}
static int asm9260_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
u32 ctime0, ctime1, ctime2;
ctime0 = ioread32(priv->iobase + HW_CTIME0);
ctime1 = ioread32(priv->iobase + HW_CTIME1);
ctime2 = ioread32(priv->iobase + HW_CTIME2);
if (ctime1 != ioread32(priv->iobase + HW_CTIME1)) {
/*
* woops, counter flipped right now. Now we are safe
* to reread.
*/
ctime0 = ioread32(priv->iobase + HW_CTIME0);
ctime1 = ioread32(priv->iobase + HW_CTIME1);
ctime2 = ioread32(priv->iobase + HW_CTIME2);
}
tm->tm_sec = (ctime0 >> BM_CTIME0_SEC_S) & BM_CTIME0_SEC_M;
tm->tm_min = (ctime0 >> BM_CTIME0_MIN_S) & BM_CTIME0_MIN_M;
tm->tm_hour = (ctime0 >> BM_CTIME0_HOUR_S) & BM_CTIME0_HOUR_M;
tm->tm_wday = (ctime0 >> BM_CTIME0_DOW_S) & BM_CTIME0_DOW_M;
tm->tm_mday = (ctime1 >> BM_CTIME1_DOM_S) & BM_CTIME1_DOM_M;
tm->tm_mon = (ctime1 >> BM_CTIME1_MON_S) & BM_CTIME1_MON_M;
tm->tm_year = (ctime1 >> BM_CTIME1_YEAR_S) & BM_CTIME1_YEAR_M;
tm->tm_yday = (ctime2 >> BM_CTIME2_DOY_S) & BM_CTIME2_DOY_M;
return 0;
}
static int asm9260_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
/*
* make sure SEC counter will not flip other counter on write time,
* real value will be written at the enf of sequence.
*/
iowrite32(0, priv->iobase + HW_SEC);
iowrite32(tm->tm_year, priv->iobase + HW_YEAR);
iowrite32(tm->tm_mon, priv->iobase + HW_MONTH);
iowrite32(tm->tm_mday, priv->iobase + HW_DOM);
iowrite32(tm->tm_wday, priv->iobase + HW_DOW);
iowrite32(tm->tm_yday, priv->iobase + HW_DOY);
iowrite32(tm->tm_hour, priv->iobase + HW_HOUR);
iowrite32(tm->tm_min, priv->iobase + HW_MIN);
iowrite32(tm->tm_sec, priv->iobase + HW_SEC);
return 0;
}
static int asm9260_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
alrm->time.tm_year = ioread32(priv->iobase + HW_ALYEAR);
alrm->time.tm_mon = ioread32(priv->iobase + HW_ALMON);
alrm->time.tm_mday = ioread32(priv->iobase + HW_ALDOM);
alrm->time.tm_wday = ioread32(priv->iobase + HW_ALDOW);
alrm->time.tm_yday = ioread32(priv->iobase + HW_ALDOY);
alrm->time.tm_hour = ioread32(priv->iobase + HW_ALHOUR);
alrm->time.tm_min = ioread32(priv->iobase + HW_ALMIN);
alrm->time.tm_sec = ioread32(priv->iobase + HW_ALSEC);
alrm->enabled = ioread32(priv->iobase + HW_AMR) ? 1 : 0;
alrm->pending = ioread32(priv->iobase + HW_CIIR) ? 1 : 0;
return rtc_valid_tm(&alrm->time);
}
static int asm9260_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
iowrite32(alrm->time.tm_year, priv->iobase + HW_ALYEAR);
iowrite32(alrm->time.tm_mon, priv->iobase + HW_ALMON);
iowrite32(alrm->time.tm_mday, priv->iobase + HW_ALDOM);
iowrite32(alrm->time.tm_wday, priv->iobase + HW_ALDOW);
iowrite32(alrm->time.tm_yday, priv->iobase + HW_ALDOY);
iowrite32(alrm->time.tm_hour, priv->iobase + HW_ALHOUR);
iowrite32(alrm->time.tm_min, priv->iobase + HW_ALMIN);
iowrite32(alrm->time.tm_sec, priv->iobase + HW_ALSEC);
iowrite32(alrm->enabled ? 0 : BM_AMR_OFF, priv->iobase + HW_AMR);
return 0;
}
static int asm9260_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
struct asm9260_rtc_priv *priv = dev_get_drvdata(dev);
iowrite32(enabled ? 0 : BM_AMR_OFF, priv->iobase + HW_AMR);
return 0;
}
static const struct rtc_class_ops asm9260_rtc_ops = {
.read_time = asm9260_rtc_read_time,
.set_time = asm9260_rtc_set_time,
.read_alarm = asm9260_rtc_read_alarm,
.set_alarm = asm9260_rtc_set_alarm,
.alarm_irq_enable = asm9260_alarm_irq_enable,
};
static int asm9260_rtc_probe(struct platform_device *pdev)
{
struct asm9260_rtc_priv *priv;
struct device *dev = &pdev->dev;
int irq_alarm, ret;
u32 ccr;
priv = devm_kzalloc(dev, sizeof(struct asm9260_rtc_priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->dev = &pdev->dev;
platform_set_drvdata(pdev, priv);
irq_alarm = platform_get_irq(pdev, 0);
if (irq_alarm < 0)
return irq_alarm;
priv->iobase = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(priv->iobase))
return PTR_ERR(priv->iobase);
priv->clk = devm_clk_get(dev, "ahb");
if (IS_ERR(priv->clk))
return PTR_ERR(priv->clk);
ret = clk_prepare_enable(priv->clk);
if (ret) {
dev_err(dev, "Failed to enable clk!\n");
return ret;
}
ccr = ioread32(priv->iobase + HW_CCR);
/* if dev is not enabled, reset it */
if ((ccr & (BM_CLKEN | BM_CTCRST)) != BM_CLKEN) {
iowrite32(BM_CTCRST, priv->iobase + HW_CCR);
ccr = 0;
}
iowrite32(BM_CLKEN | ccr, priv->iobase + HW_CCR);
iowrite32(0, priv->iobase + HW_CIIR);
iowrite32(BM_AMR_OFF, priv->iobase + HW_AMR);
priv->rtc = devm_rtc_device_register(dev, dev_name(dev),
&asm9260_rtc_ops, THIS_MODULE);
if (IS_ERR(priv->rtc)) {
ret = PTR_ERR(priv->rtc);
dev_err(dev, "Failed to register RTC device: %d\n", ret);
goto err_return;
}
ret = devm_request_threaded_irq(dev, irq_alarm, NULL,
asm9260_rtc_irq, IRQF_ONESHOT,
dev_name(dev), priv);
if (ret < 0) {
dev_err(dev, "can't get irq %i, err %d\n",
irq_alarm, ret);
goto err_return;
}
return 0;
err_return:
clk_disable_unprepare(priv->clk);
return ret;
}
static void asm9260_rtc_remove(struct platform_device *pdev)
{
struct asm9260_rtc_priv *priv = platform_get_drvdata(pdev);
/* Disable alarm matching */
iowrite32(BM_AMR_OFF, priv->iobase + HW_AMR);
clk_disable_unprepare(priv->clk);
}
static const struct of_device_id asm9260_dt_ids[] = {
{ .compatible = "alphascale,asm9260-rtc", },
{}
};
MODULE_DEVICE_TABLE(of, asm9260_dt_ids);
static struct platform_driver asm9260_rtc_driver = {
.probe = asm9260_rtc_probe,
.remove_new = asm9260_rtc_remove,
.driver = {
.name = "asm9260-rtc",
.of_match_table = asm9260_dt_ids,
},
};
module_platform_driver(asm9260_rtc_driver);
MODULE_AUTHOR("Oleksij Rempel <linux@rempel-privat.de>");
MODULE_DESCRIPTION("Alphascale asm9260 SoC Realtime Clock Driver (RTC)");
MODULE_LICENSE("GPL");