linux/include/linux/dma/edma.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (c) 2018-2019 Synopsys, Inc. and/or its affiliates.
 * Synopsys DesignWare eDMA core driver
 *
 * Author: Gustavo Pimentel <[email protected]>
 */

#ifndef _DW_EDMA_H
#define _DW_EDMA_H

#include <linux/device.h>
#include <linux/dmaengine.h>

#define EDMA_MAX_WR_CH …
#define EDMA_MAX_RD_CH …

struct dw_edma;

struct dw_edma_region { … };

/**
 * struct dw_edma_core_ops - platform-specific eDMA methods
 * @irq_vector:		Get IRQ number of the passed eDMA channel. Note the
 *			method accepts the channel id in the end-to-end
 *			numbering with the eDMA write channels being placed
 *			first in the row.
 * @pci_address:	Get PCIe bus address corresponding to the passed CPU
 *			address. Note there is no need in specifying this
 *			function if the address translation is performed by
 *			the DW PCIe RP/EP controller with the DW eDMA device in
 *			subject and DMA_BYPASS isn't set for all the outbound
 *			iATU windows. That will be done by the controller
 *			automatically.
 */
struct dw_edma_plat_ops { … };

enum dw_edma_map_format { … };

/**
 * enum dw_edma_chip_flags - Flags specific to an eDMA chip
 * @DW_EDMA_CHIP_LOCAL:		eDMA is used locally by an endpoint
 */
enum dw_edma_chip_flags { … };

/**
 * struct dw_edma_chip - representation of DesignWare eDMA controller hardware
 * @dev:		 struct device of the eDMA controller
 * @id:			 instance ID
 * @nr_irqs:		 total number of DMA IRQs
 * @ops			 DMA channel to IRQ number mapping
 * @flags		 dw_edma_chip_flags
 * @reg_base		 DMA register base address
 * @ll_wr_cnt		 DMA write link list count
 * @ll_rd_cnt		 DMA read link list count
 * @rg_region		 DMA register region
 * @ll_region_wr	 DMA descriptor link list memory for write channel
 * @ll_region_rd	 DMA descriptor link list memory for read channel
 * @dt_region_wr	 DMA data memory for write channel
 * @dt_region_rd	 DMA data memory for read channel
 * @mf			 DMA register map format
 * @dw:			 struct dw_edma that is filled by dw_edma_probe()
 */
struct dw_edma_chip { … };

/* Export to the platform drivers */
#if IS_REACHABLE(CONFIG_DW_EDMA)
int dw_edma_probe(struct dw_edma_chip *chip);
int dw_edma_remove(struct dw_edma_chip *chip);
#else
static inline int dw_edma_probe(struct dw_edma_chip *chip)
{
	return -ENODEV;
}

static inline int dw_edma_remove(struct dw_edma_chip *chip)
{
	return 0;
}
#endif /* CONFIG_DW_EDMA */

#endif /* _DW_EDMA_H */