From 26a11eb176bfd66442dd47f8aac6b8c4252bd6da Mon Sep 17 00:00:00 2001 From: Santosh Nayak Date: Mon, 19 Mar 2012 07:27:37 -0300 Subject: [PATCH] [media] dib0700: Return -EINTR and unlock mutex if locking attempts fails In 'dib0700_i2c_xfer_new()' and 'dib0700_i2c_xfer_legacy()' we are taking two locks: 1. i2c_mutex 2. usb_mutex If attempt to take 'usb_mutex' lock fails then the previously taken lock 'i2c_mutex' should be unlocked and -EINTR should be returned so that caller can take appropriate action. If locking attempt was interrupted by a signal then we should return -EINTR. At present we are returning '0' for such scenarios which is wrong. Replace -EAGAIN by -EINTR as a return type for the the scenario where locking attempt was interrupted by signal. Signed-off-by: Santosh Nayak Signed-off-by: Mauro Carvalho Chehab --- drivers/media/dvb/dvb-usb/dib0700_core.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) diff --git a/drivers/media/dvb/dvb-usb/dib0700_core.c b/drivers/media/dvb/dvb-usb/dib0700_core.c index 02290c60f72..7e9e00fae04 100644 --- a/drivers/media/dvb/dvb-usb/dib0700_core.c +++ b/drivers/media/dvb/dvb-usb/dib0700_core.c @@ -32,7 +32,7 @@ int dib0700_get_version(struct dvb_usb_device *d, u32 *hwversion, if (mutex_lock_interruptible(&d->usb_mutex) < 0) { err("could not acquire lock"); - return 0; + return -EINTR; } ret = usb_control_msg(d->udev, usb_rcvctrlpipe(d->udev, 0), @@ -118,7 +118,7 @@ int dib0700_set_gpio(struct dvb_usb_device *d, enum dib07x0_gpios gpio, u8 gpio_ if (mutex_lock_interruptible(&d->usb_mutex) < 0) { err("could not acquire lock"); - return 0; + return -EINTR; } st->buf[0] = REQUEST_SET_GPIO; @@ -139,7 +139,7 @@ static int dib0700_set_usb_xfer_len(struct dvb_usb_device *d, u16 nb_ts_packets) if (st->fw_version >= 0x10201) { if (mutex_lock_interruptible(&d->usb_mutex) < 0) { err("could not acquire lock"); - return 0; + return -EINTR; } st->buf[0] = REQUEST_SET_USB_XFER_LEN; @@ -178,7 +178,7 @@ static int dib0700_i2c_xfer_new(struct i2c_adapter *adap, struct i2c_msg *msg, /* Ensure nobody else hits the i2c bus while we're sending our sequence of messages, (such as the remote control thread) */ if (mutex_lock_interruptible(&d->i2c_mutex) < 0) - return -EAGAIN; + return -EINTR; for (i = 0; i < num; i++) { if (i == 0) { @@ -228,7 +228,8 @@ static int dib0700_i2c_xfer_new(struct i2c_adapter *adap, struct i2c_msg *msg, /* Write request */ if (mutex_lock_interruptible(&d->usb_mutex) < 0) { err("could not acquire lock"); - return 0; + mutex_unlock(&d->i2c_mutex); + return -EINTR; } st->buf[0] = REQUEST_NEW_I2C_WRITE; st->buf[1] = msg[i].addr << 1; @@ -271,10 +272,11 @@ static int dib0700_i2c_xfer_legacy(struct i2c_adapter *adap, int i,len; if (mutex_lock_interruptible(&d->i2c_mutex) < 0) - return -EAGAIN; + return -EINTR; if (mutex_lock_interruptible(&d->usb_mutex) < 0) { err("could not acquire lock"); - return 0; + mutex_unlock(&d->i2c_mutex); + return -EINTR; } for (i = 0; i < num; i++) { @@ -369,7 +371,7 @@ static int dib0700_set_clock(struct dvb_usb_device *d, u8 en_pll, if (mutex_lock_interruptible(&d->usb_mutex) < 0) { err("could not acquire lock"); - return 0; + return -EINTR; } st->buf[0] = REQUEST_SET_CLOCK; @@ -401,7 +403,7 @@ int dib0700_set_i2c_speed(struct dvb_usb_device *d, u16 scl_kHz) if (mutex_lock_interruptible(&d->usb_mutex) < 0) { err("could not acquire lock"); - return 0; + return -EINTR; } st->buf[0] = REQUEST_SET_I2C_PARAM; @@ -561,7 +563,7 @@ int dib0700_streaming_ctrl(struct dvb_usb_adapter *adap, int onoff) if (mutex_lock_interruptible(&adap->dev->usb_mutex) < 0) { err("could not acquire lock"); - return 0; + return -EINTR; } st->buf[0] = REQUEST_ENABLE_VIDEO; @@ -611,7 +613,7 @@ int dib0700_change_protocol(struct rc_dev *rc, u64 rc_type) if (mutex_lock_interruptible(&d->usb_mutex) < 0) { err("could not acquire lock"); - return 0; + return -EINTR; } st->buf[0] = REQUEST_SET_RC; -- 2.46.0