From: Jonathan Cameron on
Signed-off-by: Jonathan Cameron <jic23(a)cam.ac.uk>
---
drivers/staging/iio/iio.h | 45 +++++++++++++++++++++++++++++++++++++++++----
1 files changed, 41 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/iio/iio.h b/drivers/staging/iio/iio.h
index 71dbfe1..a12072a 100644
--- a/drivers/staging/iio/iio.h
+++ b/drivers/staging/iio/iio.h
@@ -96,6 +96,7 @@ void iio_remove_event_from_list(struct iio_event_handler_list *el,
* control method is used
* @scan_count: [INTERN] the number of elements in the current scan mode
* @scan_mask: [INTERN] bitmask used in masking scan mode elements
+ * @available_scan_masks: [DRIVER] optional array of allowed bitmasks
* @scan_timestamp: [INTERN] does the scan mode include a timestamp
* @trig: [INTERN] current device trigger (ring buffer modes)
* @pollfunc: [DRIVER] function run on trigger being recieved
@@ -122,7 +123,8 @@ struct iio_dev {
struct attribute_group *scan_el_attrs;
int scan_count;

- u16 scan_mask;
+ u32 scan_mask;
+ u32 *available_scan_masks;
bool scan_timestamp;
struct iio_trigger *trig;
struct iio_poll_func *pollfunc;
@@ -132,22 +134,57 @@ struct iio_dev {
* These are mainly provided to allow for a change of implementation if a device
* has a large number of scan elements
*/
-#define IIO_MAX_SCAN_LENGTH 15
+#define IIO_MAX_SCAN_LENGTH 31
+
+/* note 0 used as error indicator as it doesn't make sense. */
+static inline u32 iio_scan_mask_match(u32 *av_masks, u32 mask)
+{
+ while (*av_masks) {
+ if (!(~*av_masks & mask))
+ return *av_masks;
+ av_masks++;
+ }
+ return 0;
+}

static inline int iio_scan_mask_query(struct iio_dev *dev_info, int bit)
{
+ u32 mask;
+
if (bit > IIO_MAX_SCAN_LENGTH)
return -EINVAL;
+
+ if (!dev_info->scan_mask)
+ return 0;
+
+ if (dev_info->available_scan_masks)
+ mask = iio_scan_mask_match(dev_info->available_scan_masks,
+ dev_info->scan_mask);
else
- return !!(dev_info->scan_mask & (1 << bit));
+ mask = dev_info->scan_mask;
+
+ if (!mask)
+ return -EINVAL;
+
+ return !!(mask & (1 << bit));
};

static inline int iio_scan_mask_set(struct iio_dev *dev_info, int bit)
{
+ u32 mask;
+ u32 trialmask = dev_info->scan_mask | (1 << bit);
+
if (bit > IIO_MAX_SCAN_LENGTH)
return -EINVAL;
- dev_info->scan_mask |= (1 << bit);
+ if (dev_info->available_scan_masks) {
+ mask = iio_scan_mask_match(dev_info->available_scan_masks,
+ trialmask);
+ if (!mask)
+ return -EINVAL;
+ }
+ dev_info->scan_mask = trialmask;
dev_info->scan_count++;
+
return 0;
};

--
1.6.4.4

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