5 files changed, 45 insertions, 18 deletions

diff --git a/drivers/staging/comedi/comedidev.h b/drivers/staging/comedi/comedidev.h
index a7d569cfca5d..0dff1ac057cd 100644
--- a/drivers/staging/comedi/comedidev.h
+++ b/drivers/staging/comedi/comedidev.h
@@ -1001,6 +1001,8 @@ int comedi_dio_insn_config(struct comedi_device *dev,
 			   unsigned int mask);
 unsigned int comedi_dio_update_state(struct comedi_subdevice *s,
 				     unsigned int *data);
+unsigned int comedi_bytes_per_scan_cmd(struct comedi_subdevice *s,
+				       struct comedi_cmd *cmd);
 unsigned int comedi_bytes_per_scan(struct comedi_subdevice *s);
 unsigned int comedi_nscans_left(struct comedi_subdevice *s,
 				unsigned int nscans);
diff --git a/drivers/staging/comedi/drivers.c b/drivers/staging/comedi/drivers.c
index eefa62f42c0f..5a32b8fc000e 100644
--- a/drivers/staging/comedi/drivers.c
+++ b/drivers/staging/comedi/drivers.c
@@ -394,11 +394,13 @@ unsigned int comedi_dio_update_state(struct comedi_subdevice *s,
 EXPORT_SYMBOL_GPL(comedi_dio_update_state);
 
 /**
- * comedi_bytes_per_scan() - Get length of asynchronous command "scan" in bytes
+ * comedi_bytes_per_scan_cmd() - Get length of asynchronous command "scan" in
+ * bytes
  * @s: COMEDI subdevice.
+ * @cmd: COMEDI command.
  *
  * Determines the overall scan length according to the subdevice type and the
- * number of channels in the scan.
+ * number of channels in the scan for the specified command.
  *
  * For digital input, output or input/output subdevices, samples for
  * multiple channels are assumed to be packed into one or more unsigned
@@ -408,9 +410,9 @@ EXPORT_SYMBOL_GPL(comedi_dio_update_state);
  *
  * Returns the overall scan length in bytes.
  */
-unsigned int comedi_bytes_per_scan(struct comedi_subdevice *s)
+unsigned int comedi_bytes_per_scan_cmd(struct comedi_subdevice *s,
+				       struct comedi_cmd *cmd)
 {
-	struct comedi_cmd *cmd = &s->async->cmd;
 	unsigned int num_samples;
 	unsigned int bits_per_sample;
 
@@ -427,6 +429,29 @@ unsigned int comedi_bytes_per_scan(struct comedi_subdevice *s)
 	}
 	return comedi_samples_to_bytes(s, num_samples);
 }
+EXPORT_SYMBOL_GPL(comedi_bytes_per_scan_cmd);
+
+/**
+ * comedi_bytes_per_scan() - Get length of asynchronous command "scan" in bytes
+ * @s: COMEDI subdevice.
+ *
+ * Determines the overall scan length according to the subdevice type and the
+ * number of channels in the scan for the current command.
+ *
+ * For digital input, output or input/output subdevices, samples for
+ * multiple channels are assumed to be packed into one or more unsigned
+ * short or unsigned int values according to the subdevice's %SDF_LSAMPL
+ * flag.  For other types of subdevice, samples are assumed to occupy a
+ * whole unsigned short or unsigned int according to the %SDF_LSAMPL flag.
+ *
+ * Returns the overall scan length in bytes.
+ */
+unsigned int comedi_bytes_per_scan(struct comedi_subdevice *s)
+{
+	struct comedi_cmd *cmd = &s->async->cmd;
+
+	return comedi_bytes_per_scan_cmd(s, cmd);
+}
 EXPORT_SYMBOL_GPL(comedi_bytes_per_scan);
 
 static unsigned int __comedi_nscans_left(struct comedi_subdevice *s,
diff --git a/drivers/staging/comedi/drivers/ni_mio_common.c b/drivers/staging/comedi/drivers/ni_mio_common.c
index 5edf59ac6706..b04dad8c7092 100644
--- a/drivers/staging/comedi/drivers/ni_mio_common.c
+++ b/drivers/staging/comedi/drivers/ni_mio_common.c
@@ -3545,6 +3545,7 @@ static int ni_cdio_cmdtest(struct comedi_device *dev,
 			   struct comedi_subdevice *s, struct comedi_cmd *cmd)
 {
 	struct ni_private *devpriv = dev->private;
+	unsigned int bytes_per_scan;
 	int err = 0;
 
 	/* Step 1 : check if triggers are trivially valid */
@@ -3579,9 +3580,12 @@ static int ni_cdio_cmdtest(struct comedi_device *dev,
 	err |= comedi_check_trigger_arg_is(&cmd->convert_arg, 0);
 	err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg,
 					   cmd->chanlist_len);
-	err |= comedi_check_trigger_arg_max(&cmd->stop_arg,
-					    s->async->prealloc_bufsz /
-					    comedi_bytes_per_scan(s));
+	bytes_per_scan = comedi_bytes_per_scan_cmd(s, cmd);
+	if (bytes_per_scan) {
+		err |= comedi_check_trigger_arg_max(&cmd->stop_arg,
+						    s->async->prealloc_bufsz /
+						    bytes_per_scan);
+	}
 
 	if (err)
 		return 3;
diff --git a/drivers/staging/comedi/drivers/ni_usb6501.c b/drivers/staging/comedi/drivers/ni_usb6501.c
index 808ed92ed66f..1bb1cb651349 100644
--- a/drivers/staging/comedi/drivers/ni_usb6501.c
+++ b/drivers/staging/comedi/drivers/ni_usb6501.c
@@ -463,10 +463,8 @@ static int ni6501_alloc_usb_buffers(struct comedi_device *dev)
 
 	size = usb_endpoint_maxp(devpriv->ep_tx);
 	devpriv->usb_tx_buf = kzalloc(size, GFP_KERNEL);
-	if (!devpriv->usb_tx_buf) {
-		kfree(devpriv->usb_rx_buf);
+	if (!devpriv->usb_tx_buf)
 		return -ENOMEM;
-	}
 
 	return 0;
 }
@@ -518,6 +516,9 @@ static int ni6501_auto_attach(struct comedi_device *dev,
 	if (!devpriv)
 		return -ENOMEM;
 
+	mutex_init(&devpriv->mut);
+	usb_set_intfdata(intf, devpriv);
+
 	ret = ni6501_find_endpoints(dev);
 	if (ret)
 		return ret;
@@ -526,9 +527,6 @@ static int ni6501_auto_attach(struct comedi_device *dev,
 	if (ret)
 		return ret;
 
-	mutex_init(&devpriv->mut);
-	usb_set_intfdata(intf, devpriv);
-
 	ret = comedi_alloc_subdevices(dev, 2);
 	if (ret)
 		return ret;
diff --git a/drivers/staging/comedi/drivers/vmk80xx.c b/drivers/staging/comedi/drivers/vmk80xx.c
index 6234b649d887..65dc6c51037e 100644
--- a/drivers/staging/comedi/drivers/vmk80xx.c
+++ b/drivers/staging/comedi/drivers/vmk80xx.c
@@ -682,10 +682,8 @@ static int vmk80xx_alloc_usb_buffers(struct comedi_device *dev)
 
 	size = usb_endpoint_maxp(devpriv->ep_tx);
 	devpriv->usb_tx_buf = kzalloc(size, GFP_KERNEL);
-	if (!devpriv->usb_tx_buf) {
-		kfree(devpriv->usb_rx_buf);
+	if (!devpriv->usb_tx_buf)
 		return -ENOMEM;
-	}
 
 	return 0;
 }
@@ -800,6 +798,8 @@ static int vmk80xx_auto_attach(struct comedi_device *dev,
 
 	devpriv->model = board->model;
 
+	sema_init(&devpriv->limit_sem, 8);
+
 	ret = vmk80xx_find_usb_endpoints(dev);
 	if (ret)
 		return ret;
@@ -808,8 +808,6 @@ static int vmk80xx_auto_attach(struct comedi_device *dev,
 	if (ret)
 		return ret;
 
-	sema_init(&devpriv->limit_sem, 8);
-
 	usb_set_intfdata(intf, devpriv);
 
 	if (devpriv->model == VMK8055_MODEL)