Contributors: 13
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Andrew Morton |
680 |
55.51% |
3 |
13.64% |
| Linus Torvalds |
208 |
16.98% |
2 |
9.09% |
| Paul Mundt |
141 |
11.51% |
3 |
13.64% |
| Mark Glaisher |
135 |
11.02% |
1 |
4.55% |
| Linus Torvalds (pre-git) |
19 |
1.55% |
5 |
22.73% |
| David Howells |
15 |
1.22% |
1 |
4.55% |
| Adrian McMenamin |
9 |
0.73% |
1 |
4.55% |
| Vasiliy Kulikov |
5 |
0.41% |
1 |
4.55% |
| Thomas Gleixner |
4 |
0.33% |
1 |
4.55% |
| Manuel Lauss |
3 |
0.24% |
1 |
4.55% |
| Kuninori Morimoto |
3 |
0.24% |
1 |
4.55% |
| Christoph Hellwig |
2 |
0.16% |
1 |
4.55% |
| Azeem Shaikh |
1 |
0.08% |
1 |
4.55% |
| Total |
1225 |
|
22 |
|
// SPDX-License-Identifier: GPL-2.0
/*
* arch/sh/drivers/dma/dma-api.c
*
* SuperH-specific DMA management API
*
* Copyright (C) 2003, 2004, 2005 Paul Mundt
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/list.h>
#include <linux/platform_device.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <asm/dma.h>
DEFINE_SPINLOCK(dma_spin_lock);
static LIST_HEAD(registered_dmac_list);
struct dma_info *get_dma_info(unsigned int chan)
{
struct dma_info *info;
/*
* Look for each DMAC's range to determine who the owner of
* the channel is.
*/
list_for_each_entry(info, ®istered_dmac_list, list) {
if ((chan < info->first_vchannel_nr) ||
(chan >= info->first_vchannel_nr + info->nr_channels))
continue;
return info;
}
return NULL;
}
EXPORT_SYMBOL(get_dma_info);
static unsigned int get_nr_channels(void)
{
struct dma_info *info;
unsigned int nr = 0;
if (unlikely(list_empty(®istered_dmac_list)))
return nr;
list_for_each_entry(info, ®istered_dmac_list, list)
nr += info->nr_channels;
return nr;
}
struct dma_channel *get_dma_channel(unsigned int chan)
{
struct dma_info *info = get_dma_info(chan);
struct dma_channel *channel;
int i;
if (unlikely(!info))
return ERR_PTR(-EINVAL);
for (i = 0; i < info->nr_channels; i++) {
channel = &info->channels[i];
if (channel->vchan == chan)
return channel;
}
return NULL;
}
EXPORT_SYMBOL(get_dma_channel);
int get_dma_residue(unsigned int chan)
{
struct dma_info *info = get_dma_info(chan);
struct dma_channel *channel = get_dma_channel(chan);
if (info->ops->get_residue)
return info->ops->get_residue(channel);
return 0;
}
EXPORT_SYMBOL(get_dma_residue);
int request_dma(unsigned int chan, const char *dev_id)
{
struct dma_channel *channel = { 0 };
struct dma_info *info = get_dma_info(chan);
int result;
channel = get_dma_channel(chan);
if (atomic_xchg(&channel->busy, 1))
return -EBUSY;
strscpy(channel->dev_id, dev_id, sizeof(channel->dev_id));
if (info->ops->request) {
result = info->ops->request(channel);
if (result)
atomic_set(&channel->busy, 0);
return result;
}
return 0;
}
EXPORT_SYMBOL(request_dma);
void free_dma(unsigned int chan)
{
struct dma_info *info = get_dma_info(chan);
struct dma_channel *channel = get_dma_channel(chan);
if (info->ops->free)
info->ops->free(channel);
atomic_set(&channel->busy, 0);
}
EXPORT_SYMBOL(free_dma);
void dma_wait_for_completion(unsigned int chan)
{
struct dma_info *info = get_dma_info(chan);
struct dma_channel *channel = get_dma_channel(chan);
if (channel->flags & DMA_TEI_CAPABLE) {
wait_event(channel->wait_queue,
(info->ops->get_residue(channel) == 0));
return;
}
while (info->ops->get_residue(channel))
cpu_relax();
}
EXPORT_SYMBOL(dma_wait_for_completion);
void dma_configure_channel(unsigned int chan, unsigned long flags)
{
struct dma_info *info = get_dma_info(chan);
struct dma_channel *channel = get_dma_channel(chan);
if (info->ops->configure)
info->ops->configure(channel, flags);
}
EXPORT_SYMBOL(dma_configure_channel);
int dma_xfer(unsigned int chan, unsigned long from,
unsigned long to, size_t size, unsigned int mode)
{
struct dma_info *info = get_dma_info(chan);
struct dma_channel *channel = get_dma_channel(chan);
channel->sar = from;
channel->dar = to;
channel->count = size;
channel->mode = mode;
return info->ops->xfer(channel);
}
EXPORT_SYMBOL(dma_xfer);
static int dma_proc_show(struct seq_file *m, void *v)
{
struct dma_info *info = v;
if (list_empty(®istered_dmac_list))
return 0;
/*
* Iterate over each registered DMAC
*/
list_for_each_entry(info, ®istered_dmac_list, list) {
int i;
/*
* Iterate over each channel
*/
for (i = 0; i < info->nr_channels; i++) {
struct dma_channel *channel = info->channels + i;
if (!(channel->flags & DMA_CONFIGURED))
continue;
seq_printf(m, "%2d: %14s %s\n", i,
info->name, channel->dev_id);
}
}
return 0;
}
int register_dmac(struct dma_info *info)
{
unsigned int total_channels, i;
INIT_LIST_HEAD(&info->list);
printk(KERN_INFO "DMA: Registering %s handler (%d channel%s).\n",
info->name, info->nr_channels, info->nr_channels > 1 ? "s" : "");
BUG_ON((info->flags & DMAC_CHANNELS_CONFIGURED) && !info->channels);
info->pdev = platform_device_register_simple(info->name, -1,
NULL, 0);
if (IS_ERR(info->pdev))
return PTR_ERR(info->pdev);
/*
* Don't touch pre-configured channels
*/
if (!(info->flags & DMAC_CHANNELS_CONFIGURED)) {
unsigned int size;
size = sizeof(struct dma_channel) * info->nr_channels;
info->channels = kzalloc(size, GFP_KERNEL);
if (!info->channels)
return -ENOMEM;
}
total_channels = get_nr_channels();
info->first_vchannel_nr = total_channels;
for (i = 0; i < info->nr_channels; i++) {
struct dma_channel *chan = &info->channels[i];
atomic_set(&chan->busy, 0);
chan->chan = info->first_channel_nr + i;
chan->vchan = info->first_channel_nr + i + total_channels;
memcpy(chan->dev_id, "Unused", 7);
if (info->flags & DMAC_CHANNELS_TEI_CAPABLE)
chan->flags |= DMA_TEI_CAPABLE;
init_waitqueue_head(&chan->wait_queue);
dma_create_sysfs_files(chan, info);
}
list_add(&info->list, ®istered_dmac_list);
return 0;
}
EXPORT_SYMBOL(register_dmac);
void unregister_dmac(struct dma_info *info)
{
unsigned int i;
for (i = 0; i < info->nr_channels; i++)
dma_remove_sysfs_files(info->channels + i, info);
if (!(info->flags & DMAC_CHANNELS_CONFIGURED))
kfree(info->channels);
list_del(&info->list);
platform_device_unregister(info->pdev);
}
EXPORT_SYMBOL(unregister_dmac);
static int __init dma_api_init(void)
{
printk(KERN_NOTICE "DMA: Registering DMA API.\n");
return proc_create_single("dma", 0, NULL, dma_proc_show) ? 0 : -ENOMEM;
}
subsys_initcall(dma_api_init);
MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
MODULE_DESCRIPTION("DMA API for SuperH");
MODULE_LICENSE("GPL v2");