mirror of
https://github.com/FEX-Emu/linux.git
synced 2024-12-22 17:33:01 +00:00
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
104 lines
2.7 KiB
C
104 lines
2.7 KiB
C
/*
|
|
* ISA DMA support functions
|
|
* Copyright (c) by Jaroslav Kysela <perex@suse.cz>
|
|
*
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*
|
|
*/
|
|
|
|
/*
|
|
* Defining following add some delay. Maybe this helps for some broken
|
|
* ISA DMA controllers.
|
|
*/
|
|
|
|
#undef HAVE_REALLY_SLOW_DMA_CONTROLLER
|
|
|
|
#include <sound/driver.h>
|
|
#include <sound/core.h>
|
|
#include <asm/dma.h>
|
|
|
|
/**
|
|
* snd_dma_program - program an ISA DMA transfer
|
|
* @dma: the dma number
|
|
* @addr: the physical address of the buffer
|
|
* @size: the DMA transfer size
|
|
* @mode: the DMA transfer mode, DMA_MODE_XXX
|
|
*
|
|
* Programs an ISA DMA transfer for the given buffer.
|
|
*/
|
|
void snd_dma_program(unsigned long dma,
|
|
unsigned long addr, unsigned int size,
|
|
unsigned short mode)
|
|
{
|
|
unsigned long flags;
|
|
|
|
flags = claim_dma_lock();
|
|
disable_dma(dma);
|
|
clear_dma_ff(dma);
|
|
set_dma_mode(dma, mode);
|
|
set_dma_addr(dma, addr);
|
|
set_dma_count(dma, size);
|
|
if (!(mode & DMA_MODE_NO_ENABLE))
|
|
enable_dma(dma);
|
|
release_dma_lock(flags);
|
|
}
|
|
|
|
/**
|
|
* snd_dma_disable - stop the ISA DMA transfer
|
|
* @dma: the dma number
|
|
*
|
|
* Stops the ISA DMA transfer.
|
|
*/
|
|
void snd_dma_disable(unsigned long dma)
|
|
{
|
|
unsigned long flags;
|
|
|
|
flags = claim_dma_lock();
|
|
clear_dma_ff(dma);
|
|
disable_dma(dma);
|
|
release_dma_lock(flags);
|
|
}
|
|
|
|
/**
|
|
* snd_dma_pointer - return the current pointer to DMA transfer buffer in bytes
|
|
* @dma: the dma number
|
|
* @size: the dma transfer size
|
|
*
|
|
* Returns the current pointer in DMA tranfer buffer in bytes
|
|
*/
|
|
unsigned int snd_dma_pointer(unsigned long dma, unsigned int size)
|
|
{
|
|
unsigned long flags;
|
|
unsigned int result;
|
|
|
|
flags = claim_dma_lock();
|
|
clear_dma_ff(dma);
|
|
if (!isa_dma_bridge_buggy)
|
|
disable_dma(dma);
|
|
result = get_dma_residue(dma);
|
|
if (!isa_dma_bridge_buggy)
|
|
enable_dma(dma);
|
|
release_dma_lock(flags);
|
|
#ifdef CONFIG_SND_DEBUG
|
|
if (result > size)
|
|
snd_printk(KERN_ERR "pointer (0x%x) for DMA #%ld is greater than transfer size (0x%x)\n", result, dma, size);
|
|
#endif
|
|
if (result >= size || result == 0)
|
|
return 0;
|
|
else
|
|
return size - result;
|
|
}
|