linux/drivers/rtc/rtc-88pm80x.c
Colin Ian King fb0b322537 rtc: 88pm80x: fix unintended sign extension
Shifting a u8 by 24 will cause the value to be promoted to an integer. If
the top bit of the u8 is set then the following conversion to an unsigned
long will sign extend the value causing the upper 32 bits to be set in
the result.

Fix this by casting the u8 value to an unsigned long before the shift.

Detected by CoverityScan, CID#714646-714649 ("Unintended sign extension")

Fixes: 2985c29c19 ("rtc: Add rtc support to 88PM80X PMIC")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2019-02-08 09:30:13 +01:00

356 lines
9.9 KiB
C

/*
* Real Time Clock driver for Marvell 88PM80x PMIC
*
* Copyright (c) 2012 Marvell International Ltd.
* Wenzeng Chen<wzch@marvell.com>
* Qiao Zhou <zhouqiao@marvell.com>
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file "COPYING" in the main directory of this
* archive for more details.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/regmap.h>
#include <linux/mfd/core.h>
#include <linux/mfd/88pm80x.h>
#include <linux/rtc.h>
#define PM800_RTC_COUNTER1 (0xD1)
#define PM800_RTC_COUNTER2 (0xD2)
#define PM800_RTC_COUNTER3 (0xD3)
#define PM800_RTC_COUNTER4 (0xD4)
#define PM800_RTC_EXPIRE1_1 (0xD5)
#define PM800_RTC_EXPIRE1_2 (0xD6)
#define PM800_RTC_EXPIRE1_3 (0xD7)
#define PM800_RTC_EXPIRE1_4 (0xD8)
#define PM800_RTC_TRIM1 (0xD9)
#define PM800_RTC_TRIM2 (0xDA)
#define PM800_RTC_TRIM3 (0xDB)
#define PM800_RTC_TRIM4 (0xDC)
#define PM800_RTC_EXPIRE2_1 (0xDD)
#define PM800_RTC_EXPIRE2_2 (0xDE)
#define PM800_RTC_EXPIRE2_3 (0xDF)
#define PM800_RTC_EXPIRE2_4 (0xE0)
#define PM800_POWER_DOWN_LOG1 (0xE5)
#define PM800_POWER_DOWN_LOG2 (0xE6)
struct pm80x_rtc_info {
struct pm80x_chip *chip;
struct regmap *map;
struct rtc_device *rtc_dev;
struct device *dev;
int irq;
};
static irqreturn_t rtc_update_handler(int irq, void *data)
{
struct pm80x_rtc_info *info = (struct pm80x_rtc_info *)data;
int mask;
mask = PM800_ALARM | PM800_ALARM_WAKEUP;
regmap_update_bits(info->map, PM800_RTC_CONTROL, mask | PM800_ALARM1_EN,
mask);
rtc_update_irq(info->rtc_dev, 1, RTC_AF);
return IRQ_HANDLED;
}
static int pm80x_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
struct pm80x_rtc_info *info = dev_get_drvdata(dev);
if (enabled)
regmap_update_bits(info->map, PM800_RTC_CONTROL,
PM800_ALARM1_EN, PM800_ALARM1_EN);
else
regmap_update_bits(info->map, PM800_RTC_CONTROL,
PM800_ALARM1_EN, 0);
return 0;
}
/*
* Calculate the next alarm time given the requested alarm time mask
* and the current time.
*/
static void rtc_next_alarm_time(struct rtc_time *next, struct rtc_time *now,
struct rtc_time *alrm)
{
unsigned long next_time;
unsigned long now_time;
next->tm_year = now->tm_year;
next->tm_mon = now->tm_mon;
next->tm_mday = now->tm_mday;
next->tm_hour = alrm->tm_hour;
next->tm_min = alrm->tm_min;
next->tm_sec = alrm->tm_sec;
now_time = rtc_tm_to_time64(now);
next_time = rtc_tm_to_time64(next);
if (next_time < now_time) {
/* Advance one day */
next_time += 60 * 60 * 24;
rtc_time64_to_tm(next_time, next);
}
}
static int pm80x_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct pm80x_rtc_info *info = dev_get_drvdata(dev);
unsigned char buf[4];
unsigned long ticks, base, data;
regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
base = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
(buf[1] << 8) | buf[0];
dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
/* load 32-bit read-only counter */
regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
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 pm80x_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct pm80x_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 */
regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
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);
buf[0] = base & 0xFF;
buf[1] = (base >> 8) & 0xFF;
buf[2] = (base >> 16) & 0xFF;
buf[3] = (base >> 24) & 0xFF;
regmap_raw_write(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
return 0;
}
static int pm80x_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct pm80x_rtc_info *info = dev_get_drvdata(dev);
unsigned char buf[4];
unsigned long ticks, base, data;
int ret;
regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
base = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
(buf[1] << 8) | buf[0];
dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
regmap_raw_read(info->map, PM800_RTC_EXPIRE1_1, buf, 4);
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);
regmap_read(info->map, PM800_RTC_CONTROL, &ret);
alrm->enabled = (ret & PM800_ALARM1_EN) ? 1 : 0;
alrm->pending = (ret & (PM800_ALARM | PM800_ALARM_WAKEUP)) ? 1 : 0;
return 0;
}
static int pm80x_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct pm80x_rtc_info *info = dev_get_drvdata(dev);
struct rtc_time now_tm, alarm_tm;
unsigned long ticks, base, data;
unsigned char buf[4];
int mask;
regmap_update_bits(info->map, PM800_RTC_CONTROL, PM800_ALARM1_EN, 0);
regmap_raw_read(info->map, PM800_RTC_EXPIRE2_1, buf, 4);
base = ((unsigned long)buf[3] << 24) | (buf[2] << 16) |
(buf[1] << 8) | buf[0];
dev_dbg(info->dev, "%x-%x-%x-%x\n", buf[0], buf[1], buf[2], buf[3]);
/* load 32-bit read-only counter */
regmap_raw_read(info->map, PM800_RTC_COUNTER1, buf, 4);
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, &now_tm);
dev_dbg(info->dev, "%s, now time : %lu\n", __func__, ticks);
rtc_next_alarm_time(&alarm_tm, &now_tm, &alrm->time);
/* get new ticks for alarm in 24 hours */
ticks = rtc_tm_to_time64(&alarm_tm);
dev_dbg(info->dev, "%s, alarm time: %lu\n", __func__, ticks);
data = ticks - base;
buf[0] = data & 0xff;
buf[1] = (data >> 8) & 0xff;
buf[2] = (data >> 16) & 0xff;
buf[3] = (data >> 24) & 0xff;
regmap_raw_write(info->map, PM800_RTC_EXPIRE1_1, buf, 4);
if (alrm->enabled) {
mask = PM800_ALARM | PM800_ALARM_WAKEUP | PM800_ALARM1_EN;
regmap_update_bits(info->map, PM800_RTC_CONTROL, mask, mask);
} else {
mask = PM800_ALARM | PM800_ALARM_WAKEUP | PM800_ALARM1_EN;
regmap_update_bits(info->map, PM800_RTC_CONTROL, mask,
PM800_ALARM | PM800_ALARM_WAKEUP);
}
return 0;
}
static const struct rtc_class_ops pm80x_rtc_ops = {
.read_time = pm80x_rtc_read_time,
.set_time = pm80x_rtc_set_time,
.read_alarm = pm80x_rtc_read_alarm,
.set_alarm = pm80x_rtc_set_alarm,
.alarm_irq_enable = pm80x_rtc_alarm_irq_enable,
};
#ifdef CONFIG_PM_SLEEP
static int pm80x_rtc_suspend(struct device *dev)
{
return pm80x_dev_suspend(dev);
}
static int pm80x_rtc_resume(struct device *dev)
{
return pm80x_dev_resume(dev);
}
#endif
static SIMPLE_DEV_PM_OPS(pm80x_rtc_pm_ops, pm80x_rtc_suspend, pm80x_rtc_resume);
static int pm80x_rtc_probe(struct platform_device *pdev)
{
struct pm80x_chip *chip = dev_get_drvdata(pdev->dev.parent);
struct pm80x_rtc_pdata *pdata = dev_get_platdata(&pdev->dev);
struct pm80x_rtc_info *info;
struct device_node *node = pdev->dev.of_node;
int ret;
if (!pdata && !node) {
dev_err(&pdev->dev,
"pm80x-rtc requires platform data or of_node\n");
return -EINVAL;
}
if (!pdata) {
pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata) {
dev_err(&pdev->dev, "failed to allocate memory\n");
return -ENOMEM;
}
}
info =
devm_kzalloc(&pdev->dev, sizeof(struct pm80x_rtc_info), GFP_KERNEL);
if (!info)
return -ENOMEM;
info->irq = platform_get_irq(pdev, 0);
if (info->irq < 0) {
dev_err(&pdev->dev, "No IRQ resource!\n");
ret = -EINVAL;
goto out;
}
info->chip = chip;
info->map = chip->regmap;
if (!info->map) {
dev_err(&pdev->dev, "no regmap!\n");
ret = -EINVAL;
goto out;
}
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 = pm80x_request_irq(chip, info->irq, rtc_update_handler,
IRQF_ONESHOT, "rtc", info);
if (ret < 0) {
dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",
info->irq, ret);
goto out;
}
info->rtc_dev->ops = &pm80x_rtc_ops;
info->rtc_dev->range_max = U32_MAX;
ret = rtc_register_device(info->rtc_dev);
if (ret) {
dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);
goto out_rtc;
}
/*
* enable internal XO instead of internal 3.25MHz clock since it can
* free running in PMIC power-down state.
*/
regmap_update_bits(info->map, PM800_RTC_CONTROL, PM800_RTC1_USE_XO,
PM800_RTC1_USE_XO);
/* remember whether this power up is caused by PMIC RTC or not */
info->rtc_dev->dev.platform_data = &pdata->rtc_wakeup;
device_init_wakeup(&pdev->dev, 1);
return 0;
out_rtc:
pm80x_free_irq(chip, info->irq, info);
out:
return ret;
}
static int pm80x_rtc_remove(struct platform_device *pdev)
{
struct pm80x_rtc_info *info = platform_get_drvdata(pdev);
pm80x_free_irq(info->chip, info->irq, info);
return 0;
}
static struct platform_driver pm80x_rtc_driver = {
.driver = {
.name = "88pm80x-rtc",
.pm = &pm80x_rtc_pm_ops,
},
.probe = pm80x_rtc_probe,
.remove = pm80x_rtc_remove,
};
module_platform_driver(pm80x_rtc_driver);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Marvell 88PM80x RTC driver");
MODULE_AUTHOR("Qiao Zhou <zhouqiao@marvell.com>");
MODULE_ALIAS("platform:88pm80x-rtc");