diff options
| -rw-r--r-- | include/linux/dmaengine.h | 28 |
1 files changed, 16 insertions, 12 deletions
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 2910e7dadc7f..f838764993eb 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -404,14 +404,16 @@ enum dma_residue_granularity { DMA_RESIDUE_GRANULARITY_BURST = 2, }; -/* struct dma_slave_caps - expose capabilities of a slave channel only - * - * @src_addr_widths: bit mask of src addr widths the channel supports - * @dst_addr_widths: bit mask of dstn addr widths the channel supports - * @directions: bit mask of slave direction the channel supported - * since the enum dma_transfer_direction is not defined as bits for each - * type of direction, the dma controller should fill (1 << <TYPE>) and same - * should be checked by controller as well +/** + * struct dma_slave_caps - expose capabilities of a slave channel only + * @src_addr_widths: bit mask of src addr widths the channel supports. + * Width is specified in bytes, e.g. for a channel supporting + * a width of 4 the mask should have BIT(4) set. + * @dst_addr_widths: bit mask of dst addr widths the channel supports + * @directions: bit mask of slave directions the channel supports. + * Since the enum dma_transfer_direction is not defined as bit flag for + * each type, the dma controller should set BIT(<TYPE>) and same + * should be checked by controller as well * @max_burst: max burst capability per-transfer * @cmd_pause: true, if pause and thereby resume is supported * @cmd_terminate: true, if terminate cmd is supported @@ -678,11 +680,13 @@ struct dma_filter { * @dev_id: unique device ID * @dev: struct device reference for dma mapping api * @src_addr_widths: bit mask of src addr widths the device supports + * Width is specified in bytes, e.g. for a device supporting + * a width of 4 the mask should have BIT(4) set. * @dst_addr_widths: bit mask of dst addr widths the device supports - * @directions: bit mask of slave direction the device supports since - * the enum dma_transfer_direction is not defined as bits for - * each type of direction, the dma controller should fill (1 << - * <TYPE>) and same should be checked by controller as well + * @directions: bit mask of slave directions the device supports. + * Since the enum dma_transfer_direction is not defined as bit flag for + * each type, the dma controller should set BIT(<TYPE>) and same + * should be checked by controller as well * @max_burst: max burst capability per-transfer * @residue_granularity: granularity of the transfer residue reported * by tx_status |