linux/drivers/rtc/rtc-bd70528.c
Matti Vaittinen e5e3352580 rtc: bd70528: Drop BD70528 support
The only known BD70528 use-cases are such that the PMIC is controlled
from separate MCU which is not running Linux. I am not aware of
any Linux driver users. Furthermore, it seems there is no demand for
this IC. Let's ease the maintenance burden and drop the driver. We can
always add it back if there is sudden need for it.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210527105819.GA3111334@localhost.localdomain
2021-06-20 22:24:52 +02:00

361 lines
8.8 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
//
// Copyright (C) 2018 ROHM Semiconductors
//
// RTC driver for ROHM BD71828 and BD71815 PMIC
#include <linux/bcd.h>
#include <linux/mfd/rohm-bd71815.h>
#include <linux/mfd/rohm-bd71828.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/rtc.h>
/*
* On BD71828 and BD71815 the ALM0 MASK is 14 bytes after the ALM0
* block start
*/
#define BD718XX_ALM_EN_OFFSET 14
/*
* We read regs RTC_SEC => RTC_YEAR
* this struct is ordered according to chip registers.
* Keep it u8 only (or packed) to avoid padding issues.
*/
struct bd70528_rtc_day {
u8 sec;
u8 min;
u8 hour;
} __packed;
struct bd70528_rtc_data {
struct bd70528_rtc_day time;
u8 week;
u8 day;
u8 month;
u8 year;
} __packed;
struct bd71828_rtc_alm {
struct bd70528_rtc_data alm0;
struct bd70528_rtc_data alm1;
u8 alm_mask;
u8 alm1_mask;
} __packed;
struct bd70528_rtc {
struct rohm_regmap_dev *parent;
struct regmap *regmap;
struct device *dev;
u8 reg_time_start;
u8 bd718xx_alm_block_start;
};
static inline void tmday2rtc(struct rtc_time *t, struct bd70528_rtc_day *d)
{
d->sec &= ~BD70528_MASK_RTC_SEC;
d->min &= ~BD70528_MASK_RTC_MINUTE;
d->hour &= ~BD70528_MASK_RTC_HOUR;
d->sec |= bin2bcd(t->tm_sec);
d->min |= bin2bcd(t->tm_min);
d->hour |= bin2bcd(t->tm_hour);
}
static inline void tm2rtc(struct rtc_time *t, struct bd70528_rtc_data *r)
{
r->day &= ~BD70528_MASK_RTC_DAY;
r->week &= ~BD70528_MASK_RTC_WEEK;
r->month &= ~BD70528_MASK_RTC_MONTH;
/*
* PM and 24H bits are not used by Wake - thus we clear them
* here and not in tmday2rtc() which is also used by wake.
*/
r->time.hour &= ~(BD70528_MASK_RTC_HOUR_PM | BD70528_MASK_RTC_HOUR_24H);
tmday2rtc(t, &r->time);
/*
* We do always set time in 24H mode.
*/
r->time.hour |= BD70528_MASK_RTC_HOUR_24H;
r->day |= bin2bcd(t->tm_mday);
r->week |= bin2bcd(t->tm_wday);
r->month |= bin2bcd(t->tm_mon + 1);
r->year = bin2bcd(t->tm_year - 100);
}
static inline void rtc2tm(struct bd70528_rtc_data *r, struct rtc_time *t)
{
t->tm_sec = bcd2bin(r->time.sec & BD70528_MASK_RTC_SEC);
t->tm_min = bcd2bin(r->time.min & BD70528_MASK_RTC_MINUTE);
t->tm_hour = bcd2bin(r->time.hour & BD70528_MASK_RTC_HOUR);
/*
* If RTC is in 12H mode, then bit BD70528_MASK_RTC_HOUR_PM
* is not BCD value but tells whether it is AM or PM
*/
if (!(r->time.hour & BD70528_MASK_RTC_HOUR_24H)) {
t->tm_hour %= 12;
if (r->time.hour & BD70528_MASK_RTC_HOUR_PM)
t->tm_hour += 12;
}
t->tm_mday = bcd2bin(r->day & BD70528_MASK_RTC_DAY);
t->tm_mon = bcd2bin(r->month & BD70528_MASK_RTC_MONTH) - 1;
t->tm_year = 100 + bcd2bin(r->year & BD70528_MASK_RTC_YEAR);
t->tm_wday = bcd2bin(r->week & BD70528_MASK_RTC_WEEK);
}
static int bd71828_set_alarm(struct device *dev, struct rtc_wkalrm *a)
{
int ret;
struct bd71828_rtc_alm alm;
struct bd70528_rtc *r = dev_get_drvdata(dev);
ret = regmap_bulk_read(r->regmap, r->bd718xx_alm_block_start, &alm,
sizeof(alm));
if (ret) {
dev_err(dev, "Failed to read alarm regs\n");
return ret;
}
tm2rtc(&a->time, &alm.alm0);
if (!a->enabled)
alm.alm_mask &= ~BD70528_MASK_ALM_EN;
else
alm.alm_mask |= BD70528_MASK_ALM_EN;
ret = regmap_bulk_write(r->regmap, r->bd718xx_alm_block_start, &alm,
sizeof(alm));
if (ret)
dev_err(dev, "Failed to set alarm time\n");
return ret;
}
static int bd71828_read_alarm(struct device *dev, struct rtc_wkalrm *a)
{
int ret;
struct bd71828_rtc_alm alm;
struct bd70528_rtc *r = dev_get_drvdata(dev);
ret = regmap_bulk_read(r->regmap, r->bd718xx_alm_block_start, &alm,
sizeof(alm));
if (ret) {
dev_err(dev, "Failed to read alarm regs\n");
return ret;
}
rtc2tm(&alm.alm0, &a->time);
a->time.tm_mday = -1;
a->time.tm_mon = -1;
a->time.tm_year = -1;
a->enabled = !!(alm.alm_mask & BD70528_MASK_ALM_EN);
a->pending = 0;
return 0;
}
static int bd71828_set_time(struct device *dev, struct rtc_time *t)
{
int ret;
struct bd70528_rtc_data rtc_data;
struct bd70528_rtc *r = dev_get_drvdata(dev);
ret = regmap_bulk_read(r->regmap, r->reg_time_start, &rtc_data,
sizeof(rtc_data));
if (ret) {
dev_err(dev, "Failed to read RTC time registers\n");
return ret;
}
tm2rtc(t, &rtc_data);
ret = regmap_bulk_write(r->regmap, r->reg_time_start, &rtc_data,
sizeof(rtc_data));
if (ret)
dev_err(dev, "Failed to set RTC time\n");
return ret;
}
static int bd70528_get_time(struct device *dev, struct rtc_time *t)
{
struct bd70528_rtc *r = dev_get_drvdata(dev);
struct bd70528_rtc_data rtc_data;
int ret;
/* read the RTC date and time registers all at once */
ret = regmap_bulk_read(r->regmap, r->reg_time_start, &rtc_data,
sizeof(rtc_data));
if (ret) {
dev_err(dev, "Failed to read RTC time (err %d)\n", ret);
return ret;
}
rtc2tm(&rtc_data, t);
return 0;
}
static int bd71828_alm_enable(struct device *dev, unsigned int enabled)
{
int ret;
struct bd70528_rtc *r = dev_get_drvdata(dev);
unsigned int enableval = BD70528_MASK_ALM_EN;
if (!enabled)
enableval = 0;
ret = regmap_update_bits(r->regmap, r->bd718xx_alm_block_start +
BD718XX_ALM_EN_OFFSET, BD70528_MASK_ALM_EN,
enableval);
if (ret)
dev_err(dev, "Failed to change alarm state\n");
return ret;
}
static const struct rtc_class_ops bd71828_rtc_ops = {
.read_time = bd70528_get_time,
.set_time = bd71828_set_time,
.read_alarm = bd71828_read_alarm,
.set_alarm = bd71828_set_alarm,
.alarm_irq_enable = bd71828_alm_enable,
};
static irqreturn_t alm_hndlr(int irq, void *data)
{
struct rtc_device *rtc = data;
rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF | RTC_PF);
return IRQ_HANDLED;
}
static int bd70528_probe(struct platform_device *pdev)
{
struct bd70528_rtc *bd_rtc;
const struct rtc_class_ops *rtc_ops;
const char *irq_name;
int ret;
struct rtc_device *rtc;
int irq;
unsigned int hr;
u8 hour_reg;
enum rohm_chip_type chip = platform_get_device_id(pdev)->driver_data;
bd_rtc = devm_kzalloc(&pdev->dev, sizeof(*bd_rtc), GFP_KERNEL);
if (!bd_rtc)
return -ENOMEM;
bd_rtc->regmap = dev_get_regmap(pdev->dev.parent, NULL);
if (!bd_rtc->regmap) {
dev_err(&pdev->dev, "No regmap\n");
return -EINVAL;
}
bd_rtc->dev = &pdev->dev;
rtc_ops = &bd71828_rtc_ops;
switch (chip) {
case ROHM_CHIP_TYPE_BD71815:
irq_name = "bd71815-rtc-alm-0";
bd_rtc->reg_time_start = BD71815_REG_RTC_START;
/*
* See also BD718XX_ALM_EN_OFFSET:
* This works for BD71828 and BD71815 as they have same offset
* between ALM0 start and ALM0_MASK. If new ICs are to be
* added this requires proper check as ALM0_MASK is not located
* at the end of ALM0 block - but after all ALM blocks so if
* amount of ALMs differ the offset to enable/disable is likely
* to be incorrect and enable/disable must be given as own
* reg address here.
*/
bd_rtc->bd718xx_alm_block_start = BD71815_REG_RTC_ALM_START;
hour_reg = BD71815_REG_HOUR;
break;
case ROHM_CHIP_TYPE_BD71828:
irq_name = "bd71828-rtc-alm-0";
bd_rtc->reg_time_start = BD71828_REG_RTC_START;
bd_rtc->bd718xx_alm_block_start = BD71828_REG_RTC_ALM_START;
hour_reg = BD71828_REG_RTC_HOUR;
break;
default:
dev_err(&pdev->dev, "Unknown chip\n");
return -ENOENT;
}
irq = platform_get_irq_byname(pdev, irq_name);
if (irq < 0)
return irq;
platform_set_drvdata(pdev, bd_rtc);
ret = regmap_read(bd_rtc->regmap, hour_reg, &hr);
if (ret) {
dev_err(&pdev->dev, "Failed to reag RTC clock\n");
return ret;
}
if (!(hr & BD70528_MASK_RTC_HOUR_24H)) {
struct rtc_time t;
ret = rtc_ops->read_time(&pdev->dev, &t);
if (!ret)
ret = rtc_ops->set_time(&pdev->dev, &t);
if (ret) {
dev_err(&pdev->dev,
"Setting 24H clock for RTC failed\n");
return ret;
}
}
device_set_wakeup_capable(&pdev->dev, true);
device_wakeup_enable(&pdev->dev);
rtc = devm_rtc_allocate_device(&pdev->dev);
if (IS_ERR(rtc)) {
dev_err(&pdev->dev, "RTC device creation failed\n");
return PTR_ERR(rtc);
}
rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
rtc->range_max = RTC_TIMESTAMP_END_2099;
rtc->ops = rtc_ops;
/* Request alarm IRQ prior to registerig the RTC */
ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, &alm_hndlr,
IRQF_ONESHOT, "bd70528-rtc", rtc);
if (ret)
return ret;
return devm_rtc_register_device(rtc);
}
static const struct platform_device_id bd718x7_rtc_id[] = {
{ "bd71828-rtc", ROHM_CHIP_TYPE_BD71828 },
{ "bd71815-rtc", ROHM_CHIP_TYPE_BD71815 },
{ },
};
MODULE_DEVICE_TABLE(platform, bd718x7_rtc_id);
static struct platform_driver bd70528_rtc = {
.driver = {
.name = "bd70528-rtc"
},
.probe = bd70528_probe,
.id_table = bd718x7_rtc_id,
};
module_platform_driver(bd70528_rtc);
MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
MODULE_DESCRIPTION("ROHM BD71828 and BD71815 PMIC RTC driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:bd70528-rtc");