Commit | Line | Data |
---|---|---|
99edb3d1 | 1 | /* |
daaf6ff4 NV |
2 | * Copyright (C) 2007 Google, Inc. |
3 | * Copyright (c) 2011, Code Aurora Forum. All rights reserved. | |
4 | * Author: Brian Swetland <swetland@google.com> | |
5 | * | |
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. | |
9 | * | |
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. | |
14 | * | |
15 | */ | |
16 | ||
17 | #include <linux/module.h> | |
18 | #include <linux/fs.h> | |
19 | #include <linux/cdev.h> | |
20 | #include <linux/device.h> | |
21 | #include <linux/wait.h> | |
22 | ||
23 | #include <linux/tty.h> | |
24 | #include <linux/tty_driver.h> | |
25 | #include <linux/tty_flip.h> | |
26 | ||
27 | #include <mach/msm_smd.h> | |
28 | ||
29 | #define MAX_SMD_TTYS 32 | |
30 | ||
31 | struct smd_tty_info { | |
32 | struct tty_port port; | |
33 | smd_channel_t *ch; | |
34 | }; | |
35 | ||
36 | struct smd_tty_channel_desc { | |
37 | int id; | |
38 | const char *name; | |
39 | }; | |
40 | ||
41 | static struct smd_tty_info smd_tty[MAX_SMD_TTYS]; | |
42 | ||
43 | static const struct smd_tty_channel_desc smd_default_tty_channels[] = { | |
44 | { .id = 0, .name = "SMD_DS" }, | |
45 | { .id = 27, .name = "SMD_GPSNMEA" }, | |
46 | }; | |
47 | ||
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); | |
51 | ||
52 | static void smd_tty_notify(void *priv, unsigned event) | |
53 | { | |
54 | unsigned char *ptr; | |
55 | int avail; | |
56 | struct smd_tty_info *info = priv; | |
57 | struct tty_struct *tty; | |
58 | ||
59 | if (event != SMD_EVENT_DATA) | |
60 | return; | |
61 | ||
62 | tty = tty_port_tty_get(&info->port); | |
63 | if (!tty) | |
64 | return; | |
65 | ||
66 | for (;;) { | |
67 | if (test_bit(TTY_THROTTLED, &tty->flags)) | |
68 | break; | |
69 | avail = smd_read_avail(info->ch); | |
70 | if (avail == 0) | |
71 | break; | |
72 | ||
73 | avail = tty_prepare_flip_string(tty, &ptr, avail); | |
74 | ||
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 | |
78 | ** characters. | |
79 | */ | |
80 | pr_err("OOPS - smd_tty_buffer mismatch?!"); | |
81 | } | |
82 | ||
83 | tty_flip_buffer_push(tty); | |
84 | } | |
85 | ||
86 | /* XXX only when writable and necessary */ | |
87 | tty_wakeup(tty); | |
88 | tty_kref_put(tty); | |
89 | } | |
90 | ||
91 | static int smd_tty_port_activate(struct tty_port *tport, struct tty_struct *tty) | |
92 | { | |
93 | int i, res = 0; | |
94 | int n = tty->index; | |
95 | const char *name = NULL; | |
96 | struct smd_tty_info *info = smd_tty + n; | |
97 | ||
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; | |
101 | break; | |
102 | } | |
103 | } | |
104 | if (!name) | |
105 | return -ENODEV; | |
106 | ||
107 | if (info->ch) | |
108 | smd_kick(info->ch); | |
109 | else | |
110 | res = smd_open(name, &info->ch, info, smd_tty_notify); | |
111 | ||
112 | if (!res) | |
113 | tty->driver_data = info; | |
114 | ||
115 | return res; | |
116 | } | |
117 | ||
118 | static void smd_tty_port_shutdown(struct tty_port *tport) | |
119 | { | |
120 | struct smd_tty_info *info; | |
121 | struct tty_struct *tty = tty_port_tty_get(tport); | |
122 | ||
123 | info = tty->driver_data; | |
124 | if (info->ch) { | |
125 | smd_close(info->ch); | |
126 | info->ch = 0; | |
127 | } | |
128 | ||
129 | tty->driver_data = 0; | |
130 | tty_kref_put(tty); | |
131 | } | |
132 | ||
133 | static int smd_tty_open(struct tty_struct *tty, struct file *f) | |
134 | { | |
135 | struct smd_tty_info *info = smd_tty + tty->index; | |
136 | ||
137 | return tty_port_open(&info->port, tty, f); | |
138 | } | |
139 | ||
140 | static void smd_tty_close(struct tty_struct *tty, struct file *f) | |
141 | { | |
142 | struct smd_tty_info *info = tty->driver_data; | |
143 | ||
144 | tty_port_close(&info->port, tty, f); | |
145 | } | |
146 | ||
147 | static int smd_tty_write(struct tty_struct *tty, | |
148 | const unsigned char *buf, int len) | |
149 | { | |
150 | struct smd_tty_info *info = tty->driver_data; | |
151 | int avail; | |
152 | ||
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 | |
156 | */ | |
157 | avail = smd_write_avail(info->ch); | |
158 | if (len > avail) | |
159 | len = avail; | |
160 | ||
161 | return smd_write(info->ch, buf, len); | |
162 | } | |
163 | ||
164 | static int smd_tty_write_room(struct tty_struct *tty) | |
165 | { | |
166 | struct smd_tty_info *info = tty->driver_data; | |
167 | return smd_write_avail(info->ch); | |
168 | } | |
169 | ||
170 | static int smd_tty_chars_in_buffer(struct tty_struct *tty) | |
171 | { | |
172 | struct smd_tty_info *info = tty->driver_data; | |
173 | return smd_read_avail(info->ch); | |
174 | } | |
175 | ||
176 | static void smd_tty_unthrottle(struct tty_struct *tty) | |
177 | { | |
178 | struct smd_tty_info *info = tty->driver_data; | |
179 | smd_kick(info->ch); | |
180 | } | |
181 | ||
182 | static const struct tty_port_operations smd_tty_port_ops = { | |
183 | .shutdown = smd_tty_port_shutdown, | |
184 | .activate = smd_tty_port_activate, | |
185 | }; | |
186 | ||
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, | |
194 | }; | |
195 | ||
196 | static struct tty_driver *smd_tty_driver; | |
197 | ||
198 | static int __init smd_tty_init(void) | |
199 | { | |
200 | int ret, i; | |
201 | ||
202 | smd_tty_driver = alloc_tty_driver(MAX_SMD_TTYS); | |
203 | if (smd_tty_driver == 0) | |
204 | return -ENOMEM; | |
205 | ||
daaf6ff4 NV |
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); | |
220 | ||
221 | ret = tty_register_driver(smd_tty_driver); | |
222 | if (ret) | |
223 | return ret; | |
224 | ||
225 | for (i = 0; i < smd_tty_channels_len; i++) { | |
734cc178 JS |
226 | struct tty_port *port = &smd_tty[smd_tty_channels[i].id].port; |
227 | tty_port_init(port); | |
228 | port->ops = &smd_tty_port_ops; | |
229 | tty_port_register_device(port, smd_tty_driver, | |
230 | smd_tty_channels[i].id, NULL); | |
daaf6ff4 NV |
231 | } |
232 | ||
233 | return 0; | |
234 | } | |
235 | ||
236 | module_init(smd_tty_init); |