2 * Copyright (C) 2007 Google, Inc.
3 * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
4 * Author: Brian Swetland <swetland@google.com>
6 * This software is licensed under the terms of the GNU General Public
7 * License version 2, as published by the Free Software Foundation, and
8 * may be copied, distributed, and modified under those terms.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
17 #include <linux/module.h>
19 #include <linux/cdev.h>
20 #include <linux/device.h>
21 #include <linux/wait.h>
23 #include <linux/tty.h>
24 #include <linux/tty_driver.h>
25 #include <linux/tty_flip.h>
27 #include <mach/msm_smd.h>
29 #define MAX_SMD_TTYS 32
36 struct smd_tty_channel_desc {
41 static struct smd_tty_info smd_tty[MAX_SMD_TTYS];
43 static const struct smd_tty_channel_desc smd_default_tty_channels[] = {
44 { .id = 0, .name = "SMD_DS" },
45 { .id = 27, .name = "SMD_GPSNMEA" },
48 static const struct smd_tty_channel_desc *smd_tty_channels =
49 smd_default_tty_channels;
50 static int smd_tty_channels_len = ARRAY_SIZE(smd_default_tty_channels);
52 static void smd_tty_notify(void *priv, unsigned event)
56 struct smd_tty_info *info = priv;
57 struct tty_struct *tty;
59 if (event != SMD_EVENT_DATA)
62 tty = tty_port_tty_get(&info->port);
67 if (test_bit(TTY_THROTTLED, &tty->flags))
69 avail = smd_read_avail(info->ch);
73 avail = tty_prepare_flip_string(tty, &ptr, avail);
75 if (smd_read(info->ch, ptr, avail) != avail) {
76 /* shouldn't be possible since we're in interrupt
77 ** context here and nobody else could 'steal' our
80 pr_err("OOPS - smd_tty_buffer mismatch?!");
83 tty_flip_buffer_push(tty);
86 /* XXX only when writable and necessary */
91 static int smd_tty_port_activate(struct tty_port *tport, struct tty_struct *tty)
95 const char *name = NULL;
96 struct smd_tty_info *info = smd_tty + n;
98 for (i = 0; i < smd_tty_channels_len; i++) {
99 if (smd_tty_channels[i].id == n) {
100 name = smd_tty_channels[i].name;
110 res = smd_open(name, &info->ch, info, smd_tty_notify);
113 tty->driver_data = info;
118 static void smd_tty_port_shutdown(struct tty_port *tport)
120 struct smd_tty_info *info;
121 struct tty_struct *tty = tty_port_tty_get(tport);
123 info = tty->driver_data;
129 tty->driver_data = 0;
133 static int smd_tty_open(struct tty_struct *tty, struct file *f)
135 struct smd_tty_info *info = smd_tty + tty->index;
137 return tty_port_open(&info->port, tty, f);
140 static void smd_tty_close(struct tty_struct *tty, struct file *f)
142 struct smd_tty_info *info = tty->driver_data;
144 tty_port_close(&info->port, tty, f);
147 static int smd_tty_write(struct tty_struct *tty,
148 const unsigned char *buf, int len)
150 struct smd_tty_info *info = tty->driver_data;
153 /* if we're writing to a packet channel we will
154 ** never be able to write more data than there
155 ** is currently space for
157 avail = smd_write_avail(info->ch);
161 return smd_write(info->ch, buf, len);
164 static int smd_tty_write_room(struct tty_struct *tty)
166 struct smd_tty_info *info = tty->driver_data;
167 return smd_write_avail(info->ch);
170 static int smd_tty_chars_in_buffer(struct tty_struct *tty)
172 struct smd_tty_info *info = tty->driver_data;
173 return smd_read_avail(info->ch);
176 static void smd_tty_unthrottle(struct tty_struct *tty)
178 struct smd_tty_info *info = tty->driver_data;
182 static const struct tty_port_operations smd_tty_port_ops = {
183 .shutdown = smd_tty_port_shutdown,
184 .activate = smd_tty_port_activate,
187 static const struct tty_operations smd_tty_ops = {
188 .open = smd_tty_open,
189 .close = smd_tty_close,
190 .write = smd_tty_write,
191 .write_room = smd_tty_write_room,
192 .chars_in_buffer = smd_tty_chars_in_buffer,
193 .unthrottle = smd_tty_unthrottle,
196 static struct tty_driver *smd_tty_driver;
198 static int __init smd_tty_init(void)
202 smd_tty_driver = alloc_tty_driver(MAX_SMD_TTYS);
203 if (smd_tty_driver == 0)
206 smd_tty_driver->driver_name = "smd_tty_driver";
207 smd_tty_driver->name = "smd";
208 smd_tty_driver->major = 0;
209 smd_tty_driver->minor_start = 0;
210 smd_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
211 smd_tty_driver->subtype = SERIAL_TYPE_NORMAL;
212 smd_tty_driver->init_termios = tty_std_termios;
213 smd_tty_driver->init_termios.c_iflag = 0;
214 smd_tty_driver->init_termios.c_oflag = 0;
215 smd_tty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
216 smd_tty_driver->init_termios.c_lflag = 0;
217 smd_tty_driver->flags = TTY_DRIVER_RESET_TERMIOS |
218 TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
219 tty_set_operations(smd_tty_driver, &smd_tty_ops);
221 ret = tty_register_driver(smd_tty_driver);
225 for (i = 0; i < smd_tty_channels_len; i++) {
226 struct tty_port *port = &smd_tty[smd_tty_channels[i].id].port;
228 port->ops = &smd_tty_port_ops;
229 tty_port_register_device(port, smd_tty_driver,
230 smd_tty_channels[i].id, NULL);
236 module_init(smd_tty_init);