107 lines
2.7 KiB
C
107 lines
2.7 KiB
C
/*
|
|
* arch/sh/drivers/dma/dma-isa.c
|
|
*
|
|
* Generic ISA DMA wrapper for SH DMA API
|
|
*
|
|
* Copyright (C) 2003, 2004 Paul Mundt
|
|
*
|
|
* This file is subject to the terms and conditions of the GNU General Public
|
|
* License. See the file "COPYING" in the main directory of this archive
|
|
* for more details.
|
|
*/
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <asm/dma.h>
|
|
|
|
/*
|
|
* This implements a small wrapper set to make code using the old ISA DMA API
|
|
* work with the SH DMA API. Since most of the work in the new API happens
|
|
* at ops->xfer() time, we simply use the various set_dma_xxx() routines to
|
|
* fill in per-channel info, and then hand hand this off to ops->xfer() at
|
|
* enable_dma() time.
|
|
*
|
|
* For channels that are doing on-demand data transfer via cascading, the
|
|
* channel itself will still need to be configured through the new API. As
|
|
* such, this code is meant for only the simplest of tasks (and shouldn't be
|
|
* used in any new drivers at all).
|
|
*
|
|
* NOTE: ops->xfer() is the preferred way of doing things. However, there
|
|
* are some users of the ISA DMA API that exist in common code that we
|
|
* don't necessarily want to go out of our way to break, so we still
|
|
* allow for some compatability at that level. Any new code is strongly
|
|
* advised to run far away from the ISA DMA API and use the SH DMA API
|
|
* directly.
|
|
*/
|
|
unsigned long claim_dma_lock(void)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&dma_spin_lock, flags);
|
|
|
|
return flags;
|
|
}
|
|
EXPORT_SYMBOL(claim_dma_lock);
|
|
|
|
void release_dma_lock(unsigned long flags)
|
|
{
|
|
spin_unlock_irqrestore(&dma_spin_lock, flags);
|
|
}
|
|
EXPORT_SYMBOL(release_dma_lock);
|
|
|
|
void disable_dma(unsigned int chan)
|
|
{
|
|
/* Nothing */
|
|
}
|
|
EXPORT_SYMBOL(disable_dma);
|
|
|
|
void enable_dma(unsigned int chan)
|
|
{
|
|
struct dma_info *info = get_dma_info(chan);
|
|
struct dma_channel *channel = &info->channels[chan];
|
|
|
|
info->ops->xfer(channel);
|
|
}
|
|
EXPORT_SYMBOL(enable_dma);
|
|
|
|
void clear_dma_ff(unsigned int chan)
|
|
{
|
|
/* Nothing */
|
|
}
|
|
EXPORT_SYMBOL(clear_dma_ff);
|
|
|
|
void set_dma_mode(unsigned int chan, char mode)
|
|
{
|
|
struct dma_info *info = get_dma_info(chan);
|
|
struct dma_channel *channel = &info->channels[chan];
|
|
|
|
channel->mode = mode;
|
|
}
|
|
EXPORT_SYMBOL(set_dma_mode);
|
|
|
|
void set_dma_addr(unsigned int chan, unsigned int addr)
|
|
{
|
|
struct dma_info *info = get_dma_info(chan);
|
|
struct dma_channel *channel = &info->channels[chan];
|
|
|
|
/*
|
|
* Single address mode is the only thing supported through
|
|
* this interface.
|
|
*/
|
|
if ((channel->mode & DMA_MODE_MASK) == DMA_MODE_READ) {
|
|
channel->sar = addr;
|
|
} else {
|
|
channel->dar = addr;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(set_dma_addr);
|
|
|
|
void set_dma_count(unsigned int chan, unsigned int count)
|
|
{
|
|
struct dma_info *info = get_dma_info(chan);
|
|
struct dma_channel *channel = &info->channels[chan];
|
|
|
|
channel->count = count;
|
|
}
|
|
EXPORT_SYMBOL(set_dma_count);
|
|
|