drivers/rtc/rtc-ds1343.c: fix potential race condition
Avoid the potential race condition by avoiding bailing out of driver in
probe after registering with rtc subsystem
Also the set_alarm , read_alarm and alarm_irq_enable returns error if irq
registration fails in probe.
Also the sysfs will not create entry for alarm if irq registration fails
in probe.
Signed-off-by: Raghavendra Chandra Ganiga <ravi23ganiga@gmail.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rtc/rtc-ds1343.c b/drivers/rtc/rtc-ds1343.c
index 8ccc750..c371918 100644
--- a/drivers/rtc/rtc-ds1343.c
+++ b/drivers/rtc/rtc-ds1343.c
@@ -80,6 +80,7 @@
struct regmap *map;
struct mutex mutex;
unsigned int irqen;
+ int irq;
int alarm_sec;
int alarm_min;
int alarm_hour;
@@ -262,28 +263,32 @@
static int ds1343_sysfs_register(struct device *dev)
{
+ struct ds1343_priv *priv = dev_get_drvdata(dev);
int err;
err = device_create_file(dev, &dev_attr_glitch_filter);
if (err)
return err;
- err = device_create_file(dev, &dev_attr_alarm_status);
+ err = device_create_file(dev, &dev_attr_trickle_charger);
if (err)
goto error1;
+ if (priv->irq <= 0)
+ return err;
+
err = device_create_file(dev, &dev_attr_alarm_mode);
if (err)
goto error2;
- err = device_create_file(dev, &dev_attr_trickle_charger);
+ err = device_create_file(dev, &dev_attr_alarm_status);
if (!err)
return err;
device_remove_file(dev, &dev_attr_alarm_mode);
error2:
- device_remove_file(dev, &dev_attr_alarm_status);
+ device_remove_file(dev, &dev_attr_trickle_charger);
error1:
device_remove_file(dev, &dev_attr_glitch_filter);
@@ -293,10 +298,16 @@
static void ds1343_sysfs_unregister(struct device *dev)
{
+ struct ds1343_priv *priv = dev_get_drvdata(dev);
+
device_remove_file(dev, &dev_attr_glitch_filter);
+ device_remove_file(dev, &dev_attr_trickle_charger);
+
+ if (priv->irq <= 0)
+ return;
+
device_remove_file(dev, &dev_attr_alarm_status);
device_remove_file(dev, &dev_attr_alarm_mode);
- device_remove_file(dev, &dev_attr_trickle_charger);
}
static int ds1343_read_time(struct device *dev, struct rtc_time *dt)
@@ -415,11 +426,10 @@
static int ds1343_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
- struct spi_device *spi = priv->spi;
int res = 0;
unsigned int stat;
- if (spi->irq <= 0)
+ if (priv->irq <= 0)
return -EINVAL;
mutex_lock(&priv->mutex);
@@ -450,10 +460,9 @@
static int ds1343_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
- struct spi_device *spi = priv->spi;
int res = 0;
- if (spi->irq <= 0)
+ if (priv->irq <= 0)
return -EINVAL;
mutex_lock(&priv->mutex);
@@ -476,10 +485,9 @@
static int ds1343_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
struct ds1343_priv *priv = dev_get_drvdata(dev);
- struct spi_device *spi = priv->spi;
int res = 0;
- if (spi->irq <= 0)
+ if (priv->irq <= 0)
return -EINVAL;
mutex_lock(&priv->mutex);
@@ -593,18 +601,20 @@
return PTR_ERR(priv->rtc);
}
- if (spi->irq >= 0) {
+ priv->irq = spi->irq;
+
+ if (priv->irq >= 0) {
res = devm_request_threaded_irq(&spi->dev, spi->irq, NULL,
ds1343_thread,
IRQF_NO_SUSPEND | IRQF_ONESHOT,
"ds1343", priv);
if (res) {
+ priv->irq = -1;
dev_err(&spi->dev,
"unable to request irq for rtc ds1343\n");
- return res;
+ } else {
+ device_set_wakeup_capable(&spi->dev, 1);
}
-
- device_set_wakeup_capable(&spi->dev, 1);
}
res = ds1343_sysfs_register(&spi->dev);