alistair23-linux/include/linux/of_dma.h
Lars-Peter Clausen 8552bb4f16 dma: of: Remove check on always true condition
Both of_dma_nbcells field of the of_dma_controller and the args_count field of
the dma_spec are initialized by parsing the #dma-cells attribute of their device
tree node. So if the device tree nodes of a DMA controller and the dma_spec
match this means that of_dma_nbcells and args_count will also match. So the
second test in the of_dma_find_controller loop is redundant because given the
first test yields true the second test will also yield true. So we can safely
remove the test whether of_dma_nbcells matches args_count. Since this was the
last user of the of_dma_nbcells field we can remove it altogether.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-06-12 07:49:19 +05:30

72 lines
1.7 KiB
C

/*
* OF helpers for DMA request / controller
*
* Based on of_gpio.h
*
* Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef __LINUX_OF_DMA_H
#define __LINUX_OF_DMA_H
#include <linux/of.h>
#include <linux/dmaengine.h>
struct device_node;
struct of_dma {
struct list_head of_dma_controllers;
struct device_node *of_node;
struct dma_chan *(*of_dma_xlate)
(struct of_phandle_args *, struct of_dma *);
void *of_dma_data;
};
struct of_dma_filter_info {
dma_cap_mask_t dma_cap;
dma_filter_fn filter_fn;
};
#ifdef CONFIG_OF
extern int of_dma_controller_register(struct device_node *np,
struct dma_chan *(*of_dma_xlate)
(struct of_phandle_args *, struct of_dma *),
void *data);
extern void of_dma_controller_free(struct device_node *np);
extern struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
const char *name);
extern struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
struct of_dma *ofdma);
#else
static inline int of_dma_controller_register(struct device_node *np,
struct dma_chan *(*of_dma_xlate)
(struct of_phandle_args *, struct of_dma *),
void *data)
{
return -ENODEV;
}
static inline void of_dma_controller_free(struct device_node *np)
{
}
static inline struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
const char *name)
{
return NULL;
}
static inline struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
struct of_dma *ofdma)
{
return NULL;
}
#endif
#endif /* __LINUX_OF_DMA_H */