diff options
| -rw-r--r-- | drivers/iio/industrialio-buffer.c | 46 | ||||
| -rw-r--r-- | include/linux/iio/buffer.h | 4 | ||||
| -rw-r--r-- | include/linux/iio/iio-opaque.h | 4 |
3 files changed, 54 insertions, 0 deletions
diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c index a95cc2da56be..4209e933ab80 100644 --- a/drivers/iio/industrialio-buffer.c +++ b/drivers/iio/industrialio-buffer.c @@ -1732,6 +1732,52 @@ int iio_push_to_buffers(struct iio_dev *indio_dev, const void *data) EXPORT_SYMBOL_GPL(iio_push_to_buffers); /** + * iio_push_to_buffers_with_ts_unaligned() - push to registered buffer, + * no alignment or space requirements. + * @indio_dev: iio_dev structure for device. + * @data: channel data excluding the timestamp. + * @data_sz: size of data. + * @timestamp: timestamp for the sample data. + * + * This special variant of iio_push_to_buffers_with_timestamp() does + * not require space for the timestamp, or 8 byte alignment of data. + * It does however require an allocation on first call and additional + * copies on all calls, so should be avoided if possible. + */ +int iio_push_to_buffers_with_ts_unaligned(struct iio_dev *indio_dev, + const void *data, + size_t data_sz, + int64_t timestamp) +{ + struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev); + + /* + * Conservative estimate - we can always safely copy the minimum + * of either the data provided or the length of the destination buffer. + * This relaxed limit allows the calling drivers to be lax about + * tracking the size of the data they are pushing, at the cost of + * unnecessary copying of padding. + */ + data_sz = min_t(size_t, indio_dev->scan_bytes, data_sz); + if (iio_dev_opaque->bounce_buffer_size != indio_dev->scan_bytes) { + void *bb; + + bb = devm_krealloc(&indio_dev->dev, + iio_dev_opaque->bounce_buffer, + indio_dev->scan_bytes, GFP_KERNEL); + if (!bb) + return -ENOMEM; + iio_dev_opaque->bounce_buffer = bb; + iio_dev_opaque->bounce_buffer_size = indio_dev->scan_bytes; + } + memcpy(iio_dev_opaque->bounce_buffer, data, data_sz); + return iio_push_to_buffers_with_timestamp(indio_dev, + iio_dev_opaque->bounce_buffer, + timestamp); +} +EXPORT_SYMBOL_GPL(iio_push_to_buffers_with_ts_unaligned); + +/** * iio_buffer_release() - Free a buffer's resources * @ref: Pointer to the kref embedded in the iio_buffer struct * diff --git a/include/linux/iio/buffer.h b/include/linux/iio/buffer.h index b6928ac5c63d..451379a3984a 100644 --- a/include/linux/iio/buffer.h +++ b/include/linux/iio/buffer.h @@ -38,6 +38,10 @@ static inline int iio_push_to_buffers_with_timestamp(struct iio_dev *indio_dev, return iio_push_to_buffers(indio_dev, data); } +int iio_push_to_buffers_with_ts_unaligned(struct iio_dev *indio_dev, + const void *data, size_t data_sz, + int64_t timestamp); + bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev, const unsigned long *mask); diff --git a/include/linux/iio/iio-opaque.h b/include/linux/iio/iio-opaque.h index c9504e9da571..2be12b7b5dc5 100644 --- a/include/linux/iio/iio-opaque.h +++ b/include/linux/iio/iio-opaque.h @@ -23,6 +23,8 @@ * @groupcounter: index of next attribute group * @legacy_scan_el_group: attribute group for legacy scan elements attribute group * @legacy_buffer_group: attribute group for legacy buffer attributes group + * @bounce_buffer: for devices that call iio_push_to_buffers_with_timestamp_unaligned() + * @bounce_buffer_size: size of currently allocate bounce buffer * @scan_index_timestamp: cache of the index to the timestamp * @clock_id: timestamping clock posix identifier * @chrdev: associated character device @@ -50,6 +52,8 @@ struct iio_dev_opaque { int groupcounter; struct attribute_group legacy_scan_el_group; struct attribute_group legacy_buffer_group; + void *bounce_buffer; + size_t bounce_buffer_size; unsigned int scan_index_timestamp; clockid_t clock_id; |