-/* $Id: dma.c,v 1.7 1994/12/28 03:35:33 root Exp root $
+/*
* linux/kernel/dma.c: A DMA channel allocator. Inspired by linux/kernel/irq.c.
*
* Written by Hennus Bergman, 1992.
#include <asm/dma.h>
#include <asm/system.h>
-
+
/* A note on resource allocation:
*
};
+/**
+ * request_dma - request and reserve a system DMA channel
+ * @dmanr: DMA channel number
+ * @device_id: reserving device ID string, used in /proc/dma
+ */
int request_dma(unsigned int dmanr, const char * device_id)
{
if (dmanr >= MAX_DMA_CHANNELS)
return 0;
} /* request_dma */
-
+/**
+ * free_dma - free a reserved system DMA channel
+ * @dmanr: DMA channel number
+ */
void free_dma(unsigned int dmanr)
{
if (dmanr >= MAX_DMA_CHANNELS) {
if (xchg(&dma_chan_busy[dmanr].lock, 0) == 0) {
printk(KERN_WARNING "Trying to free free DMA%d\n", dmanr);
return;
- }
+ }
} /* free_dma */
for (i = 0 ; i < MAX_DMA_CHANNELS ; i++) {
if (dma_chan_busy[i].lock) {
- seq_printf(m, "%2d: %s\n", i,
- dma_chan_busy[i].device_id);
+ seq_printf(m, "%2d: %s\n", i,
+ dma_chan_busy[i].device_id);
}
}
return 0;
return single_open(file, proc_dma_show, NULL);
}
-static struct file_operations proc_dma_operations = {
+static const struct file_operations proc_dma_operations = {
.open = proc_dma_open,
.read = seq_read,
.llseek = seq_lseek,
static int __init proc_dma_init(void)
{
- struct proc_dir_entry *e;
-
- e = create_proc_entry("dma", 0, NULL);
- if (e)
- e->proc_fops = &proc_dma_operations;
-
+ proc_create("dma", 0, NULL, &proc_dma_operations);
return 0;
}