diff options
Diffstat (limited to 'include/dma-uclass.h')
| -rw-r--r-- | include/dma-uclass.h | 91 |
1 files changed, 90 insertions, 1 deletions
diff --git a/include/dma-uclass.h b/include/dma-uclass.h index 7bec5d3399..31b43fb4b9 100644 --- a/include/dma-uclass.h +++ b/include/dma-uclass.h @@ -1,7 +1,7 @@ /* SPDX-License-Identifier: GPL-2.0+ */ /* * Copyright (C) 2018 Álvaro Fernández Rojas <noltari@gmail.com> - * Copyright (C) 2015 Texas Instruments Incorporated <www.ti.com> + * Copyright (C) 2015 - 2018 Texas Instruments Incorporated <www.ti.com> * Written by Mugunthan V N <mugunthanvnm@ti.com> * */ @@ -13,6 +13,8 @@ #include <dma.h> +struct ofnode_phandle_args; + /* * struct dma_ops - Driver model DMA operations * @@ -20,6 +22,93 @@ * driver model. */ struct dma_ops { +#ifdef CONFIG_DMA_CHANNELS + /** + * of_xlate - Translate a client's device-tree (OF) DMA specifier. + * + * The DMA core calls this function as the first step in implementing + * a client's dma_get_by_*() call. + * + * If this function pointer is set to NULL, the DMA core will use a + * default implementation, which assumes #dma-cells = <1>, and that + * the DT cell contains a simple integer DMA Channel. + * + * At present, the DMA API solely supports device-tree. If this + * changes, other xxx_xlate() functions may be added to support those + * other mechanisms. + * + * @dma: The dma struct to hold the translation result. + * @args: The dma specifier values from device tree. + * @return 0 if OK, or a negative error code. + */ + int (*of_xlate)(struct dma *dma, + struct ofnode_phandle_args *args); + /** + * request - Request a translated DMA. + * + * The DMA core calls this function as the second step in + * implementing a client's dma_get_by_*() call, following a successful + * xxx_xlate() call, or as the only step in implementing a client's + * dma_request() call. + * + * @dma: The DMA struct to request; this has been filled in by + * a previoux xxx_xlate() function call, or by the caller of + * dma_request(). + * @return 0 if OK, or a negative error code. + */ + int (*request)(struct dma *dma); + /** + * free - Free a previously requested dma. + * + * This is the implementation of the client dma_free() API. + * + * @dma: The DMA to free. + * @return 0 if OK, or a negative error code. + */ + int (*free)(struct dma *dma); + /** + * enable() - Enable a DMA Channel. + * + * @dma: The DMA Channel to manipulate. + * @return zero on success, or -ve error code. + */ + int (*enable)(struct dma *dma); + /** + * disable() - Disable a DMA Channel. + * + * @dma: The DMA Channel to manipulate. + * @return zero on success, or -ve error code. + */ + int (*disable)(struct dma *dma); + /** + * prepare_rcv_buf() - Prepare/Add receive DMA buffer. + * + * @dma: The DMA Channel to manipulate. + * @dst: The receive buffer pointer. + * @size: The receive buffer size + * @return zero on success, or -ve error code. + */ + int (*prepare_rcv_buf)(struct dma *dma, void *dst, size_t size); + /** + * receive() - Receive a DMA transfer. + * + * @dma: The DMA Channel to manipulate. + * @dst: The destination pointer. + * @metadata: DMA driver's specific data + * @return zero on success, or -ve error code. + */ + int (*receive)(struct dma *dma, void **dst, void *metadata); + /** + * send() - Send a DMA transfer. + * + * @dma: The DMA Channel to manipulate. + * @src: The source pointer. + * @len: Length of the data to be sent (number of bytes). + * @metadata: DMA driver's specific data + * @return zero on success, or -ve error code. + */ + int (*send)(struct dma *dma, void *src, size_t len, void *metadata); +#endif /* CONFIG_DMA_CHANNELS */ /** * transfer() - Issue a DMA transfer. The implementation must * wait until the transfer is done. |