fsldma: improved DMA_SLAVE support

Now that the generic DMAEngine API has support for scatterlist to
scatterlist copying, the device_prep_slave_sg() portion of the
DMA_SLAVE API is no longer necessary and has been removed.

However, the device_control() portion of the DMA_SLAVE API is still
useful to control device specific parameters, such as externally
controlled DMA transfers and maximum burst length.

A special dma_ctrl_cmd has been added to enable externally controlled
DMA transfers. This is currently specific to the Freescale DMA
controller, but can easily be made generic when another user is found.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 0 insertions, 137 deletions

diff --git a/arch/powerpc/include/asm/fsldma.h b/arch/powerpc/include/asm/fsldma.h
deleted file mode 100644
index debc5ed96d6e..000000000000
--- a/arch/powerpc/include/asm/fsldma.h
+++ /dev/null
@@ -1,137 +0,0 @@
-/*
- * Freescale MPC83XX / MPC85XX DMA Controller
- *
- * Copyright (c) 2009 Ira W. Snyder <iws@ovro.caltech.edu>
- *
- * This file is licensed under the terms of the GNU General Public License
- * version 2. This program is licensed "as is" without any warranty of any
- * kind, whether express or implied.
- */
-
-#ifndef __ARCH_POWERPC_ASM_FSLDMA_H__
-#define __ARCH_POWERPC_ASM_FSLDMA_H__
-
-#include <linux/slab.h>
-#include <linux/dmaengine.h>
-
-/*
- * Definitions for the Freescale DMA controller's DMA_SLAVE implemention
- *
- * The Freescale DMA_SLAVE implementation was designed to handle many-to-many
- * transfers. An example usage would be an accelerated copy between two
- * scatterlists. Another example use would be an accelerated copy from
- * multiple non-contiguous device buffers into a single scatterlist.
- *
- * A DMA_SLAVE transaction is defined by a struct fsl_dma_slave. This
- * structure contains a list of hardware addresses that should be copied
- * to/from the scatterlist passed into device_prep_slave_sg(). The structure
- * also has some fields to enable hardware-specific features.
- */
-
-/**
- * struct fsl_dma_hw_addr
- * @entry: linked list entry
- * @address: the hardware address
- * @length: length to transfer
- *
- * Holds a single physical hardware address / length pair for use
- * with the DMAEngine DMA_SLAVE API.
- */
-struct fsl_dma_hw_addr {
-	struct list_head entry;
-
-	dma_addr_t address;
-	size_t length;
-};
-
-/**
- * struct fsl_dma_slave
- * @addresses: a linked list of struct fsl_dma_hw_addr structures
- * @request_count: value for DMA request count
- * @src_loop_size: setup and enable constant source-address DMA transfers
- * @dst_loop_size: setup and enable constant destination address DMA transfers
- * @external_start: enable externally started DMA transfers
- * @external_pause: enable externally paused DMA transfers
- *
- * Holds a list of address / length pairs for use with the DMAEngine
- * DMA_SLAVE API implementation for the Freescale DMA controller.
- */
-struct fsl_dma_slave {
-
-	/* List of hardware address/length pairs */
-	struct list_head addresses;
-
-	/* Support for extra controller features */
-	unsigned int request_count;
-	unsigned int src_loop_size;
-	unsigned int dst_loop_size;
-	bool external_start;
-	bool external_pause;
-};
-
-/**
- * fsl_dma_slave_append - add an address/length pair to a struct fsl_dma_slave
- * @slave: the &struct fsl_dma_slave to add to
- * @address: the hardware address to add
- * @length: the length of bytes to transfer from @address
- *
- * Add a hardware address/length pair to a struct fsl_dma_slave. Returns 0 on
- * success, -ERRNO otherwise.
- */
-static inline int fsl_dma_slave_append(struct fsl_dma_slave *slave,
-				       dma_addr_t address, size_t length)
-{
-	struct fsl_dma_hw_addr *addr;
-
-	addr = kzalloc(sizeof(*addr), GFP_ATOMIC);
-	if (!addr)
-		return -ENOMEM;
-
-	INIT_LIST_HEAD(&addr->entry);
-	addr->address = address;
-	addr->length = length;
-
-	list_add_tail(&addr->entry, &slave->addresses);
-	return 0;
-}
-
-/**
- * fsl_dma_slave_free - free a struct fsl_dma_slave
- * @slave: the struct fsl_dma_slave to free
- *
- * Free a struct fsl_dma_slave and all associated address/length pairs
- */
-static inline void fsl_dma_slave_free(struct fsl_dma_slave *slave)
-{
-	struct fsl_dma_hw_addr *addr, *tmp;
-
-	if (slave) {
-		list_for_each_entry_safe(addr, tmp, &slave->addresses, entry) {
-			list_del(&addr->entry);
-			kfree(addr);
-		}
-
-		kfree(slave);
-	}
-}
-
-/**
- * fsl_dma_slave_alloc - allocate a struct fsl_dma_slave
- * @gfp: the flags to pass to kmalloc when allocating this structure
- *
- * Allocate a struct fsl_dma_slave for use by the DMA_SLAVE API. Returns a new
- * struct fsl_dma_slave on success, or NULL on failure.
- */
-static inline struct fsl_dma_slave *fsl_dma_slave_alloc(gfp_t gfp)
-{
-	struct fsl_dma_slave *slave;
-
-	slave = kzalloc(sizeof(*slave), gfp);
-	if (!slave)
-		return NULL;
-
-	INIT_LIST_HEAD(&slave->addresses);
-	return slave;
-}
-
-#endif /* __ARCH_POWERPC_ASM_FSLDMA_H__ */