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Diffstat (limited to 'arch/arm/kernel/dma.c')
-rw-r--r--arch/arm/kernel/dma.c154
1 files changed, 94 insertions, 60 deletions
diff --git a/arch/arm/kernel/dma.c b/arch/arm/kernel/dma.c
index ba99a203552..7b829d9663b 100644
--- a/arch/arm/kernel/dma.c
+++ b/arch/arm/kernel/dma.c
@@ -15,31 +15,38 @@
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/errno.h>
+#include <linux/scatterlist.h>
+#include <linux/seq_file.h>
+#include <linux/proc_fs.h>
#include <asm/dma.h>
#include <asm/mach/dma.h>
-DEFINE_SPINLOCK(dma_spin_lock);
+DEFINE_RAW_SPINLOCK(dma_spin_lock);
EXPORT_SYMBOL(dma_spin_lock);
-static dma_t dma_chan[MAX_DMA_CHANNELS];
+static dma_t *dma_chan[MAX_DMA_CHANNELS];
-/*
- * Get dma list for /proc/dma
- */
-int get_dma_list(char *buf)
+static inline dma_t *dma_channel(unsigned int chan)
{
- dma_t *dma;
- char *p = buf;
- int i;
+ if (chan >= MAX_DMA_CHANNELS)
+ return NULL;
+
+ return dma_chan[chan];
+}
- for (i = 0, dma = dma_chan; i < MAX_DMA_CHANNELS; i++, dma++)
- if (dma->lock)
- p += sprintf(p, "%2d: %14s %s\n", i,
- dma->d_ops->type, dma->device_id);
+int __init isa_dma_add(unsigned int chan, dma_t *dma)
+{
+ if (!dma->d_ops)
+ return -EINVAL;
+
+ sg_init_table(&dma->buf, 1);
- return p - buf;
+ if (dma_chan[chan])
+ return -EBUSY;
+ dma_chan[chan] = dma;
+ return 0;
}
/*
@@ -47,12 +54,12 @@ int get_dma_list(char *buf)
*
* On certain platforms, we have to allocate an interrupt as well...
*/
-int request_dma(dmach_t channel, const char *device_id)
+int request_dma(unsigned int chan, const char *device_id)
{
- dma_t *dma = dma_chan + channel;
+ dma_t *dma = dma_channel(chan);
int ret;
- if (channel >= MAX_DMA_CHANNELS || !dma->d_ops)
+ if (!dma)
goto bad_dma;
if (xchg(&dma->lock, 1) != 0)
@@ -64,7 +71,7 @@ int request_dma(dmach_t channel, const char *device_id)
ret = 0;
if (dma->d_ops->request)
- ret = dma->d_ops->request(channel, dma);
+ ret = dma->d_ops->request(chan, dma);
if (ret)
xchg(&dma->lock, 0);
@@ -72,7 +79,7 @@ int request_dma(dmach_t channel, const char *device_id)
return ret;
bad_dma:
- printk(KERN_ERR "dma: trying to allocate DMA%d\n", channel);
+ printk(KERN_ERR "dma: trying to allocate DMA%d\n", chan);
return -EINVAL;
busy:
@@ -85,42 +92,42 @@ EXPORT_SYMBOL(request_dma);
*
* On certain platforms, we have to free interrupt as well...
*/
-void free_dma(dmach_t channel)
+void free_dma(unsigned int chan)
{
- dma_t *dma = dma_chan + channel;
+ dma_t *dma = dma_channel(chan);
- if (channel >= MAX_DMA_CHANNELS || !dma->d_ops)
+ if (!dma)
goto bad_dma;
if (dma->active) {
- printk(KERN_ERR "dma%d: freeing active DMA\n", channel);
- dma->d_ops->disable(channel, dma);
+ printk(KERN_ERR "dma%d: freeing active DMA\n", chan);
+ dma->d_ops->disable(chan, dma);
dma->active = 0;
}
if (xchg(&dma->lock, 0) != 0) {
if (dma->d_ops->free)
- dma->d_ops->free(channel, dma);
+ dma->d_ops->free(chan, dma);
return;
}
- printk(KERN_ERR "dma%d: trying to free free DMA\n", channel);
+ printk(KERN_ERR "dma%d: trying to free free DMA\n", chan);
return;
bad_dma:
- printk(KERN_ERR "dma: trying to free DMA%d\n", channel);
+ printk(KERN_ERR "dma: trying to free DMA%d\n", chan);
}
EXPORT_SYMBOL(free_dma);
/* Set DMA Scatter-Gather list
*/
-void set_dma_sg (dmach_t channel, struct scatterlist *sg, int nr_sg)
+void set_dma_sg (unsigned int chan, struct scatterlist *sg, int nr_sg)
{
- dma_t *dma = dma_chan + channel;
+ dma_t *dma = dma_channel(chan);
if (dma->active)
printk(KERN_ERR "dma%d: altering DMA SG while "
- "DMA active\n", channel);
+ "DMA active\n", chan);
dma->sg = sg;
dma->sgcount = nr_sg;
@@ -132,13 +139,13 @@ EXPORT_SYMBOL(set_dma_sg);
*
* Copy address to the structure, and set the invalid bit
*/
-void __set_dma_addr (dmach_t channel, void *addr)
+void __set_dma_addr (unsigned int chan, void *addr)
{
- dma_t *dma = dma_chan + channel;
+ dma_t *dma = dma_channel(chan);
if (dma->active)
printk(KERN_ERR "dma%d: altering DMA address while "
- "DMA active\n", channel);
+ "DMA active\n", chan);
dma->sg = NULL;
dma->addr = addr;
@@ -150,13 +157,13 @@ EXPORT_SYMBOL(__set_dma_addr);
*
* Copy address to the structure, and set the invalid bit
*/
-void set_dma_count (dmach_t channel, unsigned long count)
+void set_dma_count (unsigned int chan, unsigned long count)
{
- dma_t *dma = dma_chan + channel;
+ dma_t *dma = dma_channel(chan);
if (dma->active)
printk(KERN_ERR "dma%d: altering DMA count while "
- "DMA active\n", channel);
+ "DMA active\n", chan);
dma->sg = NULL;
dma->count = count;
@@ -166,13 +173,13 @@ EXPORT_SYMBOL(set_dma_count);
/* Set DMA direction mode
*/
-void set_dma_mode (dmach_t channel, dmamode_t mode)
+void set_dma_mode (unsigned int chan, unsigned int mode)
{
- dma_t *dma = dma_chan + channel;
+ dma_t *dma = dma_channel(chan);
if (dma->active)
printk(KERN_ERR "dma%d: altering DMA mode while "
- "DMA active\n", channel);
+ "DMA active\n", chan);
dma->dma_mode = mode;
dma->invalid = 1;
@@ -181,42 +188,42 @@ EXPORT_SYMBOL(set_dma_mode);
/* Enable DMA channel
*/
-void enable_dma (dmach_t channel)
+void enable_dma (unsigned int chan)
{
- dma_t *dma = dma_chan + channel;
+ dma_t *dma = dma_channel(chan);
if (!dma->lock)
goto free_dma;
if (dma->active == 0) {
dma->active = 1;
- dma->d_ops->enable(channel, dma);
+ dma->d_ops->enable(chan, dma);
}
return;
free_dma:
- printk(KERN_ERR "dma%d: trying to enable free DMA\n", channel);
+ printk(KERN_ERR "dma%d: trying to enable free DMA\n", chan);
BUG();
}
EXPORT_SYMBOL(enable_dma);
/* Disable DMA channel
*/
-void disable_dma (dmach_t channel)
+void disable_dma (unsigned int chan)
{
- dma_t *dma = dma_chan + channel;
+ dma_t *dma = dma_channel(chan);
if (!dma->lock)
goto free_dma;
if (dma->active == 1) {
dma->active = 0;
- dma->d_ops->disable(channel, dma);
+ dma->d_ops->disable(chan, dma);
}
return;
free_dma:
- printk(KERN_ERR "dma%d: trying to disable free DMA\n", channel);
+ printk(KERN_ERR "dma%d: trying to disable free DMA\n", chan);
BUG();
}
EXPORT_SYMBOL(disable_dma);
@@ -224,45 +231,72 @@ EXPORT_SYMBOL(disable_dma);
/*
* Is the specified DMA channel active?
*/
-int dma_channel_active(dmach_t channel)
+int dma_channel_active(unsigned int chan)
{
- return dma_chan[channel].active;
+ dma_t *dma = dma_channel(chan);
+ return dma->active;
}
EXPORT_SYMBOL(dma_channel_active);
-void set_dma_page(dmach_t channel, char pagenr)
+void set_dma_page(unsigned int chan, char pagenr)
{
- printk(KERN_ERR "dma%d: trying to set_dma_page\n", channel);
+ printk(KERN_ERR "dma%d: trying to set_dma_page\n", chan);
}
EXPORT_SYMBOL(set_dma_page);
-void set_dma_speed(dmach_t channel, int cycle_ns)
+void set_dma_speed(unsigned int chan, int cycle_ns)
{
- dma_t *dma = dma_chan + channel;
+ dma_t *dma = dma_channel(chan);
int ret = 0;
if (dma->d_ops->setspeed)
- ret = dma->d_ops->setspeed(channel, dma, cycle_ns);
+ ret = dma->d_ops->setspeed(chan, dma, cycle_ns);
dma->speed = ret;
}
EXPORT_SYMBOL(set_dma_speed);
-int get_dma_residue(dmach_t channel)
+int get_dma_residue(unsigned int chan)
{
- dma_t *dma = dma_chan + channel;
+ dma_t *dma = dma_channel(chan);
int ret = 0;
if (dma->d_ops->residue)
- ret = dma->d_ops->residue(channel, dma);
+ ret = dma->d_ops->residue(chan, dma);
return ret;
}
EXPORT_SYMBOL(get_dma_residue);
-static int __init init_dma(void)
+#ifdef CONFIG_PROC_FS
+static int proc_dma_show(struct seq_file *m, void *v)
+{
+ int i;
+
+ for (i = 0 ; i < MAX_DMA_CHANNELS ; i++) {
+ dma_t *dma = dma_channel(i);
+ if (dma && dma->lock)
+ seq_printf(m, "%2d: %s\n", i, dma->device_id);
+ }
+ return 0;
+}
+
+static int proc_dma_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, proc_dma_show, NULL);
+}
+
+static const struct file_operations proc_dma_operations = {
+ .open = proc_dma_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int __init proc_dma_init(void)
{
- arch_dma_init(dma_chan);
+ proc_create("dma", 0, NULL, &proc_dma_operations);
return 0;
}
-core_initcall(init_dma);
+__initcall(proc_dma_init);
+#endif
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-10 05:24:48 +0000