fpgafs/files.c

75 lines
1.5 KiB
C

/*********************************************
* Benjamin Krill <ben@codiert.org>
*********************************************/
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/version.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include "fpgafs.h"
/* generic open function for all pipe-like files */
static int fpgafs_pipe_open(struct inode *inode, struct file *file)
{
struct fpgafs_inode_info *i = FPGAFS_I(inode);
file->private_data = i->i_ctx;
return nonseekable_open(inode, file);
}
static ssize_t fpgafs_stat_read(struct file *file, char __user *buf,
size_t len, loff_t *pos)
{
struct fpga_context *ctx = file->private_data;
u32 data, __user *udata;
ssize_t count;
if (len < 4)
return -EINVAL;
if (!access_ok(VERIFY_WRITE, buf, len))
return -EFAULT;
udata = (void __user *)buf;
for (count = 0; (count + 4) <= len; count += 4, udata++) {
int ret;
/* operation to read the status ... */
data=0x42;
ret = 0;
if (ret == 0)
break;
ret = __put_user(data, udata);
if (ret) {
if (!count)
count = -EFAULT;
break;
}
}
if (!count)
count = -EAGAIN;
return count;
}
static const struct file_operations fpgafs_stat_fops = {
.open = fpgafs_pipe_open,
.read = fpgafs_stat_read,
};
struct tree_descr fpgafs_dir_contents[] = {
#if 0
{ "cmd", &fpgafs_cmd_fops, 0222, },
{ "din", &spufs_mbox_fops, 0222, },
{ "dout", &spufs_ibox_fops, 0444, },
{ "load", &spufs_wbox_fops, 0666, },
#endif
{ "stat", &fpgafs_stat_fops, 0444, },
{},
};