linux/drivers/rtc/rtc-88pm860x.c
Uwe Kleine-König 8fbff75e2b rtc: 88pm860x: 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/20230304133028.2135435-3-u.kleine-koenig@pengutronix.de
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2023-03-17 23:03:16 +01:00

382 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Real Time Clock driver for Marvell 88PM860x PMIC
*
* Copyright (c) 2010 Marvell International Ltd.
* Author: Haojian Zhuang <haojian.zhuang@marvell.com>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/rtc.h>
#include <linux/delay.h>
#include <linux/mfd/core.h>
#include <linux/mfd/88pm860x.h>
#define VRTC_CALIBRATION
struct pm860x_rtc_info {
struct pm860x_chip *chip;
struct i2c_client *i2c;
struct rtc_device *rtc_dev;
struct device *dev;
struct delayed_work calib_work;
int irq;
int vrtc;
};
#define REG_VRTC_MEAS1 0x7D
#define REG0_ADDR 0xB0
#define REG1_ADDR 0xB2
#define REG2_ADDR 0xB4
#define REG3_ADDR 0xB6
#define REG0_DATA 0xB1
#define REG1_DATA 0xB3
#define REG2_DATA 0xB5
#define REG3_DATA 0xB7
/* bit definitions of Measurement Enable Register 2 (0x51) */
#define MEAS2_VRTC (1 << 0)
/* bit definitions of RTC Register 1 (0xA0) */
#define ALARM_EN (1 << 3)
#define ALARM_WAKEUP (1 << 4)
#define ALARM (1 << 5)
#define RTC1_USE_XO (1 << 7)
#define VRTC_CALIB_INTERVAL (HZ * 60 * 10) /* 10 minutes */
static irqreturn_t rtc_update_handler(int irq, void *data)
{
struct pm860x_rtc_info *info = (struct pm860x_rtc_info *)data;
int mask;
mask = ALARM | ALARM_WAKEUP;
pm860x_set_bits(info->i2c, PM8607_RTC1, mask | ALARM_EN, mask);
rtc_update_irq(info->rtc_dev, 1, RTC_AF);
return IRQ_HANDLED;
}
static int pm860x_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
struct pm860x_rtc_info *info = dev_get_drvdata(dev);
if (enabled)
pm860x_set_bits(info->i2c, PM8607_RTC1, ALARM_EN, ALARM_EN);
else
pm860x_set_bits(info->i2c, PM8607_RTC1, ALARM_EN, 0);
return 0;
}
static int pm860x_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct pm860x_rtc_info *info = dev_get_drvdata(dev);
unsigned char buf[8];
unsigned long ticks, base, data;
pm860x_page_bulk_read(info->i2c, REG0_ADDR, 8, buf);
dev_dbg(info->dev, "%x-%x-%x-%x-%x-%x-%x-%x\n", buf[0], buf[1],
buf[2], buf[3], buf[4], buf[5], buf[6], buf[7]);
base = ((unsigned long)buf[1] << 24) | (buf[3] << 16) |
(buf[5] << 8) | buf[7];
/* load 32-bit read-only counter */
pm860x_bulk_read(info->i2c, PM8607_RTC_COUNTER1, 4, buf);
data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
(buf[1] << 8) | buf[0];
ticks = base + data;
dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
base, data, ticks);
rtc_time64_to_tm(ticks, tm);
return 0;
}
static int pm860x_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct pm860x_rtc_info *info = dev_get_drvdata(dev);
unsigned char buf[4];
unsigned long ticks, base, data;
ticks = rtc_tm_to_time64(tm);
/* load 32-bit read-only counter */
pm860x_bulk_read(info->i2c, PM8607_RTC_COUNTER1, 4, buf);
data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
(buf[1] << 8) | buf[0];
base = ticks - data;
dev_dbg(info->dev, "set base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
base, data, ticks);
pm860x_page_reg_write(info->i2c, REG0_DATA, (base >> 24) & 0xFF);
pm860x_page_reg_write(info->i2c, REG1_DATA, (base >> 16) & 0xFF);
pm860x_page_reg_write(info->i2c, REG2_DATA, (base >> 8) & 0xFF);
pm860x_page_reg_write(info->i2c, REG3_DATA, base & 0xFF);
return 0;
}
static int pm860x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct pm860x_rtc_info *info = dev_get_drvdata(dev);
unsigned char buf[8];
unsigned long ticks, base, data;
int ret;
pm860x_page_bulk_read(info->i2c, REG0_ADDR, 8, buf);
dev_dbg(info->dev, "%x-%x-%x-%x-%x-%x-%x-%x\n", buf[0], buf[1],
buf[2], buf[3], buf[4], buf[5], buf[6], buf[7]);
base = ((unsigned long)buf[1] << 24) | (buf[3] << 16) |
(buf[5] << 8) | buf[7];
pm860x_bulk_read(info->i2c, PM8607_RTC_EXPIRE1, 4, buf);
data = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
(buf[1] << 8) | buf[0];
ticks = base + data;
dev_dbg(info->dev, "get base:0x%lx, RO count:0x%lx, ticks:0x%lx\n",
base, data, ticks);
rtc_time64_to_tm(ticks, &alrm->time);
ret = pm860x_reg_read(info->i2c, PM8607_RTC1);
alrm->enabled = (ret & ALARM_EN) ? 1 : 0;
alrm->pending = (ret & (ALARM | ALARM_WAKEUP)) ? 1 : 0;
return 0;
}
static int pm860x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct pm860x_rtc_info *info = dev_get_drvdata(dev);
unsigned long ticks, base, data;
unsigned char buf[8];
int mask;
pm860x_set_bits(info->i2c, PM8607_RTC1, ALARM_EN, 0);
pm860x_page_bulk_read(info->i2c, REG0_ADDR, 8, buf);
dev_dbg(info->dev, "%x-%x-%x-%x-%x-%x-%x-%x\n", buf[0], buf[1],
buf[2], buf[3], buf[4], buf[5], buf[6], buf[7]);
base = ((unsigned long)buf[1] << 24) | (buf[3] << 16) |
(buf[5] << 8) | buf[7];
ticks = rtc_tm_to_time64(&alrm->time);
data = ticks - base;
buf[0] = data & 0xff;
buf[1] = (data >> 8) & 0xff;
buf[2] = (data >> 16) & 0xff;
buf[3] = (data >> 24) & 0xff;
pm860x_bulk_write(info->i2c, PM8607_RTC_EXPIRE1, 4, buf);
if (alrm->enabled) {
mask = ALARM | ALARM_WAKEUP | ALARM_EN;
pm860x_set_bits(info->i2c, PM8607_RTC1, mask, mask);
} else {
mask = ALARM | ALARM_WAKEUP | ALARM_EN;
pm860x_set_bits(info->i2c, PM8607_RTC1, mask,
ALARM | ALARM_WAKEUP);
}
return 0;
}
static const struct rtc_class_ops pm860x_rtc_ops = {
.read_time = pm860x_rtc_read_time,
.set_time = pm860x_rtc_set_time,
.read_alarm = pm860x_rtc_read_alarm,
.set_alarm = pm860x_rtc_set_alarm,
.alarm_irq_enable = pm860x_rtc_alarm_irq_enable,
};
#ifdef VRTC_CALIBRATION
static void calibrate_vrtc_work(struct work_struct *work)
{
struct pm860x_rtc_info *info = container_of(work,
struct pm860x_rtc_info, calib_work.work);
unsigned char buf[2];
unsigned int sum, data, mean, vrtc_set;
int i;
for (i = 0, sum = 0; i < 16; i++) {
msleep(100);
pm860x_bulk_read(info->i2c, REG_VRTC_MEAS1, 2, buf);
data = (buf[0] << 4) | buf[1];
data = (data * 5400) >> 12; /* convert to mv */
sum += data;
}
mean = sum >> 4;
vrtc_set = 2700 + (info->vrtc & 0x3) * 200;
dev_dbg(info->dev, "mean:%d, vrtc_set:%d\n", mean, vrtc_set);
sum = pm860x_reg_read(info->i2c, PM8607_RTC_MISC1);
data = sum & 0x3;
if ((mean + 200) < vrtc_set) {
/* try higher voltage */
if (++data == 4)
goto out;
data = (sum & 0xf8) | (data & 0x3);
pm860x_reg_write(info->i2c, PM8607_RTC_MISC1, data);
} else if ((mean - 200) > vrtc_set) {
/* try lower voltage */
if (data-- == 0)
goto out;
data = (sum & 0xf8) | (data & 0x3);
pm860x_reg_write(info->i2c, PM8607_RTC_MISC1, data);
} else
goto out;
dev_dbg(info->dev, "set 0x%x to RTC_MISC1\n", data);
/* trigger next calibration since VRTC is updated */
schedule_delayed_work(&info->calib_work, VRTC_CALIB_INTERVAL);
return;
out:
/* disable measurement */
pm860x_set_bits(info->i2c, PM8607_MEAS_EN2, MEAS2_VRTC, 0);
dev_dbg(info->dev, "finish VRTC calibration\n");
return;
}
#endif
#ifdef CONFIG_OF
static int pm860x_rtc_dt_init(struct platform_device *pdev,
struct pm860x_rtc_info *info)
{
struct device_node *np = pdev->dev.parent->of_node;
int ret;
if (!np)
return -ENODEV;
np = of_get_child_by_name(np, "rtc");
if (!np) {
dev_err(&pdev->dev, "failed to find rtc node\n");
return -ENODEV;
}
ret = of_property_read_u32(np, "marvell,88pm860x-vrtc", &info->vrtc);
if (ret)
info->vrtc = 0;
of_node_put(np);
return 0;
}
#else
#define pm860x_rtc_dt_init(x, y) do { } while (0)
#endif
static int pm860x_rtc_probe(struct platform_device *pdev)
{
struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
struct pm860x_rtc_info *info;
int ret;
info = devm_kzalloc(&pdev->dev, sizeof(struct pm860x_rtc_info),
GFP_KERNEL);
if (!info)
return -ENOMEM;
info->irq = platform_get_irq(pdev, 0);
if (info->irq < 0)
return info->irq;
info->chip = chip;
info->i2c = (chip->id == CHIP_PM8607) ? chip->client : chip->companion;
info->dev = &pdev->dev;
dev_set_drvdata(&pdev->dev, info);
info->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
if (IS_ERR(info->rtc_dev))
return PTR_ERR(info->rtc_dev);
ret = devm_request_threaded_irq(&pdev->dev, info->irq, NULL,
rtc_update_handler, IRQF_ONESHOT, "rtc",
info);
if (ret < 0) {
dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
info->irq, ret);
return ret;
}
/* set addresses of 32-bit base value for RTC time */
pm860x_page_reg_write(info->i2c, REG0_ADDR, REG0_DATA);
pm860x_page_reg_write(info->i2c, REG1_ADDR, REG1_DATA);
pm860x_page_reg_write(info->i2c, REG2_ADDR, REG2_DATA);
pm860x_page_reg_write(info->i2c, REG3_ADDR, REG3_DATA);
pm860x_rtc_dt_init(pdev, info);
info->rtc_dev->ops = &pm860x_rtc_ops;
info->rtc_dev->range_max = U32_MAX;
ret = devm_rtc_register_device(info->rtc_dev);
if (ret)
return ret;
/*
* enable internal XO instead of internal 3.25MHz clock since it can
* free running in PMIC power-down state.
*/
pm860x_set_bits(info->i2c, PM8607_RTC1, RTC1_USE_XO, RTC1_USE_XO);
#ifdef VRTC_CALIBRATION
/* <00> -- 2.7V, <01> -- 2.9V, <10> -- 3.1V, <11> -- 3.3V */
pm860x_set_bits(info->i2c, PM8607_MEAS_EN2, MEAS2_VRTC, MEAS2_VRTC);
/* calibrate VRTC */
INIT_DELAYED_WORK(&info->calib_work, calibrate_vrtc_work);
schedule_delayed_work(&info->calib_work, VRTC_CALIB_INTERVAL);
#endif /* VRTC_CALIBRATION */
device_init_wakeup(&pdev->dev, 1);
return 0;
}
static void pm860x_rtc_remove(struct platform_device *pdev)
{
struct pm860x_rtc_info *info = platform_get_drvdata(pdev);
#ifdef VRTC_CALIBRATION
cancel_delayed_work_sync(&info->calib_work);
/* disable measurement */
pm860x_set_bits(info->i2c, PM8607_MEAS_EN2, MEAS2_VRTC, 0);
#endif /* VRTC_CALIBRATION */
}
#ifdef CONFIG_PM_SLEEP
static int pm860x_rtc_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
if (device_may_wakeup(dev))
chip->wakeup_flag |= 1 << PM8607_IRQ_RTC;
return 0;
}
static int pm860x_rtc_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
if (device_may_wakeup(dev))
chip->wakeup_flag &= ~(1 << PM8607_IRQ_RTC);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(pm860x_rtc_pm_ops, pm860x_rtc_suspend, pm860x_rtc_resume);
static struct platform_driver pm860x_rtc_driver = {
.driver = {
.name = "88pm860x-rtc",
.pm = &pm860x_rtc_pm_ops,
},
.probe = pm860x_rtc_probe,
.remove_new = pm860x_rtc_remove,
};
module_platform_driver(pm860x_rtc_driver);
MODULE_DESCRIPTION("Marvell 88PM860x RTC driver");
MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
MODULE_LICENSE("GPL");