/*
* ISA DMA support functions
- * Copyright (c) by Jaroslav Kysela <perex@suse.cz>
+ * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
*
*
* This program is free software; you can redistribute it and/or modify
#undef HAVE_REALLY_SLOW_DMA_CONTROLLER
-#include <sound/driver.h>
#include <sound/core.h>
#include <asm/dma.h>
release_dma_lock(flags);
}
+EXPORT_SYMBOL(snd_dma_program);
+
/**
* snd_dma_disable - stop the ISA DMA transfer
* @dma: the dma number
release_dma_lock(flags);
}
+EXPORT_SYMBOL(snd_dma_disable);
+
/**
* snd_dma_pointer - return the current pointer to DMA transfer buffer in bytes
* @dma: the dma number
unsigned int snd_dma_pointer(unsigned long dma, unsigned int size)
{
unsigned long flags;
- unsigned int result;
+ unsigned int result, result1;
flags = claim_dma_lock();
clear_dma_ff(dma);
if (!isa_dma_bridge_buggy)
disable_dma(dma);
result = get_dma_residue(dma);
+ /*
+ * HACK - read the counter again and choose higher value in order to
+ * avoid reading during counter lower byte roll over if the
+ * isa_dma_bridge_buggy is set.
+ */
+ result1 = get_dma_residue(dma);
if (!isa_dma_bridge_buggy)
enable_dma(dma);
release_dma_lock(flags);
+ if (unlikely(result < result1))
+ result = result1;
#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);
else
return size - result;
}
+
+EXPORT_SYMBOL(snd_dma_pointer);