xref: /OK3568_Linux_fs/kernel/arch/um/drivers/tty.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
4*4882a593Smuzhiyun  */
5*4882a593Smuzhiyun 
6*4882a593Smuzhiyun #include <errno.h>
7*4882a593Smuzhiyun #include <fcntl.h>
8*4882a593Smuzhiyun #include <termios.h>
9*4882a593Smuzhiyun #include "chan_user.h"
10*4882a593Smuzhiyun #include <os.h>
11*4882a593Smuzhiyun #include <um_malloc.h>
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun struct tty_chan {
14*4882a593Smuzhiyun 	char *dev;
15*4882a593Smuzhiyun 	int raw;
16*4882a593Smuzhiyun 	struct termios tt;
17*4882a593Smuzhiyun };
18*4882a593Smuzhiyun 
tty_chan_init(char * str,int device,const struct chan_opts * opts)19*4882a593Smuzhiyun static void *tty_chan_init(char *str, int device, const struct chan_opts *opts)
20*4882a593Smuzhiyun {
21*4882a593Smuzhiyun 	struct tty_chan *data;
22*4882a593Smuzhiyun 
23*4882a593Smuzhiyun 	if (*str != ':') {
24*4882a593Smuzhiyun 		printk(UM_KERN_ERR "tty_init : channel type 'tty' must specify "
25*4882a593Smuzhiyun 		       "a device\n");
26*4882a593Smuzhiyun 		return NULL;
27*4882a593Smuzhiyun 	}
28*4882a593Smuzhiyun 	str++;
29*4882a593Smuzhiyun 
30*4882a593Smuzhiyun 	data = uml_kmalloc(sizeof(*data), UM_GFP_KERNEL);
31*4882a593Smuzhiyun 	if (data == NULL)
32*4882a593Smuzhiyun 		return NULL;
33*4882a593Smuzhiyun 	*data = ((struct tty_chan) { .dev 	= str,
34*4882a593Smuzhiyun 				     .raw 	= opts->raw });
35*4882a593Smuzhiyun 
36*4882a593Smuzhiyun 	return data;
37*4882a593Smuzhiyun }
38*4882a593Smuzhiyun 
tty_open(int input,int output,int primary,void * d,char ** dev_out)39*4882a593Smuzhiyun static int tty_open(int input, int output, int primary, void *d,
40*4882a593Smuzhiyun 		    char **dev_out)
41*4882a593Smuzhiyun {
42*4882a593Smuzhiyun 	struct tty_chan *data = d;
43*4882a593Smuzhiyun 	int fd, err, mode = 0;
44*4882a593Smuzhiyun 
45*4882a593Smuzhiyun 	if (input && output)
46*4882a593Smuzhiyun 		mode = O_RDWR;
47*4882a593Smuzhiyun 	else if (input)
48*4882a593Smuzhiyun 		mode = O_RDONLY;
49*4882a593Smuzhiyun 	else if (output)
50*4882a593Smuzhiyun 		mode = O_WRONLY;
51*4882a593Smuzhiyun 
52*4882a593Smuzhiyun 	fd = open(data->dev, mode);
53*4882a593Smuzhiyun 	if (fd < 0)
54*4882a593Smuzhiyun 		return -errno;
55*4882a593Smuzhiyun 
56*4882a593Smuzhiyun 	if (data->raw) {
57*4882a593Smuzhiyun 		CATCH_EINTR(err = tcgetattr(fd, &data->tt));
58*4882a593Smuzhiyun 		if (err)
59*4882a593Smuzhiyun 			return err;
60*4882a593Smuzhiyun 
61*4882a593Smuzhiyun 		err = raw(fd);
62*4882a593Smuzhiyun 		if (err)
63*4882a593Smuzhiyun 			return err;
64*4882a593Smuzhiyun 	}
65*4882a593Smuzhiyun 
66*4882a593Smuzhiyun 	*dev_out = data->dev;
67*4882a593Smuzhiyun 	return fd;
68*4882a593Smuzhiyun }
69*4882a593Smuzhiyun 
70*4882a593Smuzhiyun const struct chan_ops tty_ops = {
71*4882a593Smuzhiyun 	.type		= "tty",
72*4882a593Smuzhiyun 	.init		= tty_chan_init,
73*4882a593Smuzhiyun 	.open		= tty_open,
74*4882a593Smuzhiyun 	.close		= generic_close,
75*4882a593Smuzhiyun 	.read		= generic_read,
76*4882a593Smuzhiyun 	.write		= generic_write,
77*4882a593Smuzhiyun 	.console_write	= generic_console_write,
78*4882a593Smuzhiyun 	.window_size	= generic_window_size,
79*4882a593Smuzhiyun 	.free		= generic_free,
80*4882a593Smuzhiyun 	.winch		= 0,
81*4882a593Smuzhiyun };
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