Commit 9d1fa4c3 authored by Oleksij Rempel's avatar Oleksij Rempel Committed by Alexandre Belloni
Browse files

rtc: rv8803: convert spin_lock to mutex_lock 



Fix a scheduling while atomic issue caused by rv8803_set_time()
holding a spinlock during the call to i2c_smbus_read_byte_data().

Signed-off-by: default avatarOleksij Rempel <fixed-term.Oleksij.Rempel@de.bosch.com>
Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@free-electrons.com>
parent 7444845b

drivers/rtc/rtc-rv8803.c

+18 −21
Original line number Diff line number Diff line
@@ -52,7 +52,7 @@ 
struct rv8803_data {

	struct i2c_client *client;

	struct rtc_device *rtc;

	spinlock_t flags_lock;

	struct mutex flags_lock;

	u8 ctrl;

};
@@ -63,11 +63,11 @@ static irqreturn_t rv8803_handle_irq(int irq, void *dev_id) 
	unsigned long events = 0;

	int flags;



	spin_lock(&rv8803->flags_lock);

	mutex_lock(&rv8803->flags_lock);



	flags = i2c_smbus_read_byte_data(client, RV8803_FLAG);

	if (flags <= 0) {

		spin_unlock(&rv8803->flags_lock);

		mutex_unlock(&rv8803->flags_lock);

		return IRQ_NONE;

	}
@@ -102,7 +102,7 @@ static irqreturn_t rv8803_handle_irq(int irq, void *dev_id) 
					  rv8803->ctrl);

	}



	spin_unlock(&rv8803->flags_lock);

	mutex_unlock(&rv8803->flags_lock);



	return IRQ_HANDLED;

}
@@ -155,7 +155,6 @@ static int rv8803_set_time(struct device *dev, struct rtc_time *tm) 
	struct rv8803_data *rv8803 = dev_get_drvdata(dev);

	u8 date[7];

	int flags, ret;

	unsigned long irqflags;



	if ((tm->tm_year < 100) || (tm->tm_year > 199))

		return -EINVAL;
@@ -173,18 +172,18 @@ static int rv8803_set_time(struct device *dev, struct rtc_time *tm) 
	if (ret < 0)

		return ret;



	spin_lock_irqsave(&rv8803->flags_lock, irqflags);

	mutex_lock(&rv8803->flags_lock);



	flags = i2c_smbus_read_byte_data(rv8803->client, RV8803_FLAG);

	if (flags < 0) {

		spin_unlock_irqrestore(&rv8803->flags_lock, irqflags);

		mutex_unlock(&rv8803->flags_lock);

		return flags;

	}



	ret = i2c_smbus_write_byte_data(rv8803->client, RV8803_FLAG,

					flags & ~RV8803_FLAG_V2F);



	spin_unlock_irqrestore(&rv8803->flags_lock, irqflags);

	mutex_unlock(&rv8803->flags_lock);



	return ret;

}
@@ -226,7 +225,6 @@ static int rv8803_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) 
	u8 alarmvals[3];

	u8 ctrl[2];

	int ret, err;

	unsigned long irqflags;



	/* The alarm has no seconds, round up to nearest minute */

	if (alrm->time.tm_sec) {
@@ -236,11 +234,11 @@ static int rv8803_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) 
		rtc_time64_to_tm(alarm_time, &alrm->time);

	}



	spin_lock_irqsave(&rv8803->flags_lock, irqflags);

	mutex_lock(&rv8803->flags_lock);



	ret = i2c_smbus_read_i2c_block_data(client, RV8803_FLAG, 2, ctrl);

	if (ret != 2) {

		spin_unlock_irqrestore(&rv8803->flags_lock, irqflags);

		mutex_unlock(&rv8803->flags_lock);

		return ret < 0 ? ret : -EIO;

	}
@@ -253,14 +251,14 @@ static int rv8803_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) 
		err = i2c_smbus_write_byte_data(rv8803->client, RV8803_CTRL,

						rv8803->ctrl);

		if (err) {

			spin_unlock_irqrestore(&rv8803->flags_lock, irqflags);

			mutex_unlock(&rv8803->flags_lock);

			return err;

		}

	}



	ctrl[1] &= ~RV8803_FLAG_AF;

	err = i2c_smbus_write_byte_data(rv8803->client, RV8803_FLAG, ctrl[1]);

	spin_unlock_irqrestore(&rv8803->flags_lock, irqflags);

	mutex_unlock(&rv8803->flags_lock);

	if (err)

		return err;
@@ -289,7 +287,6 @@ static int rv8803_alarm_irq_enable(struct device *dev, unsigned int enabled) 
	struct i2c_client *client = to_i2c_client(dev);

	struct rv8803_data *rv8803 = dev_get_drvdata(dev);

	int ctrl, flags, err;

	unsigned long irqflags;



	ctrl = rv8803->ctrl;
@@ -305,15 +302,15 @@ static int rv8803_alarm_irq_enable(struct device *dev, unsigned int enabled) 
			ctrl &= ~RV8803_CTRL_AIE;

	}



	spin_lock_irqsave(&rv8803->flags_lock, irqflags);

	mutex_lock(&rv8803->flags_lock);

	flags = i2c_smbus_read_byte_data(client, RV8803_FLAG);

	if (flags < 0) {

		spin_unlock_irqrestore(&rv8803->flags_lock, irqflags);

		mutex_unlock(&rv8803->flags_lock);

		return flags;

	}

	flags &= ~(RV8803_FLAG_AF | RV8803_FLAG_UF);

	err = i2c_smbus_write_byte_data(client, RV8803_FLAG, flags);

	spin_unlock_irqrestore(&rv8803->flags_lock, irqflags);

	mutex_unlock(&rv8803->flags_lock);

	if (err)

		return err;
@@ -333,7 +330,6 @@ static int rv8803_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) 
	struct i2c_client *client = to_i2c_client(dev);

	struct rv8803_data *rv8803 = dev_get_drvdata(dev);

	int flags, ret = 0;

	unsigned long irqflags;



	switch (cmd) {

	case RTC_VL_READ:
@@ -355,16 +351,16 @@ static int rv8803_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) 
		return 0;



	case RTC_VL_CLR:

		spin_lock_irqsave(&rv8803->flags_lock, irqflags);

		mutex_lock(&rv8803->flags_lock);

		flags = i2c_smbus_read_byte_data(client, RV8803_FLAG);

		if (flags < 0) {

			spin_unlock_irqrestore(&rv8803->flags_lock, irqflags);

			mutex_unlock(&rv8803->flags_lock);

			return flags;

		}



		flags &= ~(RV8803_FLAG_V1F | RV8803_FLAG_V2F);

		ret = i2c_smbus_write_byte_data(client, RV8803_FLAG, flags);

		spin_unlock_irqrestore(&rv8803->flags_lock, irqflags);

		mutex_unlock(&rv8803->flags_lock);

		if (ret < 0)

			return ret;
@@ -441,6 +437,7 @@ static int rv8803_probe(struct i2c_client *client, 
	if (!rv8803)

		return -ENOMEM;



	mutex_init(&rv8803->flags_lock);

	rv8803->client = client;

	i2c_set_clientdata(client, rv8803);

CRA Git | Maintained and supported by SUSTech CRA and CCSE