/* Simple console for lguest.
*
* Copyright (C) 2006 Rusty Russell, IBM Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/err.h>
#include <linux/init.h>
#include <linux/lguest_bus.h>
#include "hvc_console.h"
static char inbuf[256];
static struct lguest_dma cons_input = { .used_len = 0,
.addr[0] = __pa(inbuf),
.len[0] = sizeof(inbuf),
.len[1] = 0 };
static int put_chars(u32 vtermno, const char *buf, int count)
{
struct lguest_dma dma;
/* FIXME: what if it's over a page boundary? */
dma.len[0] = count;
dma.len[1] = 0;
dma.addr[0] = __pa(buf);
lguest_send_dma(LGUEST_CONSOLE_DMA_KEY, &dma);
return count;
}
static int get_chars(u32 vtermno, char *buf, int count)
{
static int cons_offset;
if (!cons_input.used_len)
return 0;
if (cons_input.used_len - cons_offset < count)
count = cons_input.used_len - cons_offset;
memcpy(buf, inbuf + cons_offset, count);
cons_offset += count;
if (cons_offset == cons_input.used_len) {
cons_offset = 0;
cons_input.used_len = 0;
}
return count;
}
static struct hv_ops lguest_cons = {
.get_chars = get_chars,
.put_chars = put_chars,
};
static int __init cons_init(void)
{
if (strcmp(paravirt_ops.name, "lguest") != 0)
return 0;
return hvc_instantiate(0, 0, &lguest_cons);
}
console_initcall(cons_init);
static int lguestcons_probe(struct lguest_device *lgdev)
{
int err;
lgdev->private = hvc_alloc(0, lgdev_irq(lgdev), &lguest_cons, 256);
if (IS_ERR(lgdev->private))
return PTR_ERR(lgdev->private);
err = lguest_bind_dma(LGUEST_CONSOLE_DMA_KEY, &cons_input, 1,
lgdev_irq(lgdev));
if (err)
printk("lguest console: failed to bind buffer.\n");
return err;
}
static struct lguest_driver lguestcons_drv = {
.name = "lguestcons",
.owner = THIS_MODULE,
.device_type = LGUEST_DEVICE_T_CONSOLE,
.probe = lguestcons_probe,
};
static int __init hvc_lguest_init(void)
{
return register_lguest_driver(&lguestcons_drv);
}
module_init(hvc_lguest_init);
