Merge tag 'staging-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging tree patches from Greg Kroah-Hartman:
 "Here's the big staging tree merge for the 3.6-rc1 merge window.

  There are some patches in here outside of drivers/staging/, notibly
  the iio code (which is still stradeling the staging / not staging
  boundry), the pstore code, and the tracing code.  All of these have
  gotten acks from the various subsystem maintainers to be included in
  this tree.  The pstore and tracing patches are related, and are coming
  here as they replace one of the android staging drivers.

  Otherwise, the normal staging mess.  Lots of cleanups and a few new
  drivers (some iio drivers, and the large csr wireless driver
  abomination.)

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

Fixed up trivial conflicts in drivers/staging/comedi/drivers/s626.h and
drivers/staging/gdm72xx/netlink_k.c

* tag 'staging-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1108 commits)
  staging: csr: delete a bunch of unused library functions
  staging: csr: remove csr_utf16.c
  staging: csr: remove csr_pmem.h
  staging: csr: remove CsrPmemAlloc
  staging: csr: remove CsrPmemFree()
  staging: csr: remove CsrMemAllocDma()
  staging: csr: remove CsrMemCalloc()
  staging: csr: remove CsrMemAlloc()
  staging: csr: remove CsrMemFree() and CsrMemFreeDma()
  staging: csr: remove csr_util.h
  staging: csr: remove CsrOffSetOf()
  stating: csr: remove unneeded #includes in csr_util.c
  staging: csr: make CsrUInt16ToHex static
  staging: csr: remove CsrMemCpy()
  staging: csr: remove CsrStrLen()
  staging: csr: remove CsrVsnprintf()
  staging: csr: remove CsrStrDup
  staging: csr: remove CsrStrChr()
  staging: csr: remove CsrStrNCmp
  staging: csr: remove CsrStrCmp
  ...

1 files changed, 44 insertions, 8 deletions

diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index ac185b8694b..4add9bb40ee 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -285,11 +285,14 @@ int iio_buffer_register(struct iio_dev *indio_dev,
 	if (channels) {
 		/* new magic */
 		for (i = 0; i < num_channels; i++) {
+			if (channels[i].scan_index < 0)
+				continue;
+
 			/* Establish necessary mask length */
 			if (channels[i].scan_index >
 			    (int)indio_dev->masklength - 1)
 				indio_dev->masklength
-					= indio_dev->channels[i].scan_index + 1;
+					= channels[i].scan_index + 1;
 
 			ret = iio_buffer_add_channel_sysfs(indio_dev,
 							 &channels[i]);
@@ -553,6 +556,10 @@ int iio_sw_buffer_preenable(struct iio_dev *indio_dev)
 					    buffer->scan_mask);
 	else
 		indio_dev->active_scan_mask = buffer->scan_mask;
+
+	if (indio_dev->active_scan_mask == NULL)
+		return -EINVAL;
+
 	iio_update_demux(indio_dev);
 
 	if (indio_dev->info->update_scan_mode)
@@ -564,6 +571,31 @@ int iio_sw_buffer_preenable(struct iio_dev *indio_dev)
 EXPORT_SYMBOL(iio_sw_buffer_preenable);
 
 /**
+ * iio_validate_scan_mask_onehot() - Validates that exactly one channel is selected
+ * @indio_dev: the iio device
+ * @mask: scan mask to be checked
+ *
+ * Return true if exactly one bit is set in the scan mask, false otherwise. It
+ * can be used for devices where only one channel can be active for sampling at
+ * a time.
+ */
+bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev,
+	const unsigned long *mask)
+{
+	return bitmap_weight(mask, indio_dev->masklength) == 1;
+}
+EXPORT_SYMBOL_GPL(iio_validate_scan_mask_onehot);
+
+static bool iio_validate_scan_mask(struct iio_dev *indio_dev,
+	const unsigned long *mask)
+{
+	if (!indio_dev->setup_ops->validate_scan_mask)
+		return true;
+
+	return indio_dev->setup_ops->validate_scan_mask(indio_dev, mask);
+}
+
+/**
  * iio_scan_mask_set() - set particular bit in the scan mask
  * @buffer: the buffer whose scan mask we are interested in
  * @bit: the bit to be set.
@@ -582,27 +614,31 @@ int iio_scan_mask_set(struct iio_dev *indio_dev,
 		return -ENOMEM;
 	if (!indio_dev->masklength) {
 		WARN_ON("trying to set scanmask prior to registering buffer\n");
-		kfree(trialmask);
-		return -EINVAL;
+		goto err_invalid_mask;
 	}
 	bitmap_copy(trialmask, buffer->scan_mask, indio_dev->masklength);
 	set_bit(bit, trialmask);
 
+	if (!iio_validate_scan_mask(indio_dev, trialmask))
+		goto err_invalid_mask;
+
 	if (indio_dev->available_scan_masks) {
 		mask = iio_scan_mask_match(indio_dev->available_scan_masks,
 					   indio_dev->masklength,
 					   trialmask);
-		if (!mask) {
-			kfree(trialmask);
-			return -EINVAL;
-		}
+		if (!mask)
+			goto err_invalid_mask;
 	}
 	bitmap_copy(buffer->scan_mask, trialmask, indio_dev->masklength);
 
 	kfree(trialmask);
 
 	return 0;
-};
+
+err_invalid_mask:
+	kfree(trialmask);
+	return -EINVAL;
+}
 EXPORT_SYMBOL_GPL(iio_scan_mask_set);
 
 int iio_scan_mask_query(struct iio_dev *indio_dev,