1 /* 2 * Copyright (c) 2012 GCT Semiconductor, Inc. All rights reserved. 3 * 4 * This software is licensed under the terms of the GNU General Public 5 * License version 2, as published by the Free Software Foundation, and 6 * may be copied, distributed, and modified under those terms. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU General Public License for more details. 12 */ 13 14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 15 16 #include <linux/kernel.h> 17 #include <linux/errno.h> 18 #include <linux/init.h> 19 #include <linux/tty.h> 20 #include <linux/tty_driver.h> 21 #include <linux/tty_flip.h> 22 #include <linux/module.h> 23 #include <linux/slab.h> 24 #include <linux/usb/cdc.h> 25 #include <linux/serial.h> 26 #include "gdm_tty.h" 27 28 #define GDM_TTY_MAJOR 0 29 #define GDM_TTY_MINOR 32 30 31 #define ACM_CTRL_DTR 0x01 32 #define ACM_CTRL_RTS 0x02 33 #define ACM_CTRL_DSR 0x02 34 #define ACM_CTRL_RI 0x08 35 #define ACM_CTRL_DCD 0x01 36 37 #define WRITE_SIZE 2048 38 39 #define MUX_TX_MAX_SIZE 2048 40 41 #define gdm_tty_send(n, d, l, i, c, b) (\ 42 n->tty_dev->send_func(n->tty_dev->priv_dev, d, l, i, c, b)) 43 #define gdm_tty_recv(n, c) (\ 44 n->tty_dev->recv_func(n->tty_dev->priv_dev, c)) 45 #define gdm_tty_send_control(n, r, v, d, l) (\ 46 n->tty_dev->send_control(n->tty_dev->priv_dev, r, v, d, l)) 47 48 #define GDM_TTY_READY(gdm) (gdm && gdm->tty_dev && gdm->port.count) 49 50 struct tty_driver *gdm_driver[TTY_MAX_COUNT]; 51 struct gdm *gdm_table[TTY_MAX_COUNT][GDM_TTY_MINOR]; 52 static DEFINE_MUTEX(gdm_table_lock); 53 54 static char *DRIVER_STRING[TTY_MAX_COUNT] = {"GCTATC", "GCTDM"}; 55 static char *DEVICE_STRING[TTY_MAX_COUNT] = {"GCT-ATC", "GCT-DM"}; 56 57 static void gdm_port_destruct(struct tty_port *port) 58 { 59 struct gdm *gdm = container_of(port, struct gdm, port); 60 61 mutex_lock(&gdm_table_lock); 62 gdm_table[gdm->index][gdm->minor] = NULL; 63 mutex_unlock(&gdm_table_lock); 64 65 kfree(gdm); 66 } 67 68 static struct tty_port_operations gdm_port_ops = { 69 .destruct = gdm_port_destruct, 70 }; 71 72 static int gdm_tty_install(struct tty_driver *driver, struct tty_struct *tty) 73 { 74 struct gdm *gdm = NULL; 75 int ret; 76 int i; 77 int j; 78 79 j = GDM_TTY_MINOR; 80 for (i = 0; i < TTY_MAX_COUNT; i++) { 81 if (!strcmp(tty->driver->driver_name, DRIVER_STRING[i])) { 82 j = tty->index; 83 break; 84 } 85 } 86 87 if (j == GDM_TTY_MINOR) 88 return -ENODEV; 89 90 mutex_lock(&gdm_table_lock); 91 gdm = gdm_table[i][j]; 92 mutex_unlock(&gdm_table_lock); 93 if (gdm == NULL) 94 return -ENODEV; 95 96 tty_port_get(&gdm->port); 97 98 ret = tty_standard_install(driver, tty); 99 if (ret) { 100 tty_port_put(&gdm->port); 101 return ret; 102 } 103 104 tty->driver_data = gdm; 105 106 return 0; 107 } 108 109 static int gdm_tty_open(struct tty_struct *tty, struct file *filp) 110 { 111 struct gdm *gdm = tty->driver_data; 112 return tty_port_open(&gdm->port, tty, filp); 113 } 114 115 static void gdm_tty_cleanup(struct tty_struct *tty) 116 { 117 struct gdm *gdm = tty->driver_data; 118 tty_port_put(&gdm->port); 119 } 120 121 static void gdm_tty_hangup(struct tty_struct *tty) 122 { 123 struct gdm *gdm = tty->driver_data; 124 tty_port_hangup(&gdm->port); 125 } 126 127 static void gdm_tty_close(struct tty_struct *tty, struct file *filp) 128 { 129 struct gdm *gdm = tty->driver_data; 130 tty_port_close(&gdm->port, tty, filp); 131 } 132 133 static int gdm_tty_recv_complete(void *data, int len, int index, int minor, int complete) 134 { 135 struct gdm *gdm; 136 137 mutex_lock(&gdm_table_lock); 138 gdm = gdm_table[index][minor]; 139 mutex_unlock(&gdm_table_lock); 140 141 if (!GDM_TTY_READY(gdm)) { 142 if (complete == RECV_PACKET_PROCESS_COMPLETE) 143 gdm_tty_recv(gdm, gdm_tty_recv_complete); 144 return TO_HOST_PORT_CLOSE; 145 } 146 147 if (data && len) { 148 if (tty_buffer_request_room(&gdm->port, len) == len) { 149 tty_insert_flip_string(&gdm->port, data, len); 150 tty_flip_buffer_push(&gdm->port); 151 } else { 152 return TO_HOST_BUFFER_REQUEST_FAIL; 153 } 154 } 155 156 if (complete == RECV_PACKET_PROCESS_COMPLETE) 157 gdm_tty_recv(gdm, gdm_tty_recv_complete); 158 159 return 0; 160 } 161 162 static void gdm_tty_send_complete(void *arg) 163 { 164 struct gdm *gdm = (struct gdm *)arg; 165 166 if (!GDM_TTY_READY(gdm)) 167 return; 168 169 tty_port_tty_wakeup(&gdm->port); 170 } 171 172 static int gdm_tty_write(struct tty_struct *tty, const unsigned char *buf, int len) 173 { 174 struct gdm *gdm = tty->driver_data; 175 int remain = len; 176 int sent_len = 0; 177 int sending_len = 0; 178 179 if (!GDM_TTY_READY(gdm)) 180 return -ENODEV; 181 182 if (!len) 183 return 0; 184 185 while (1) { 186 sending_len = remain > MUX_TX_MAX_SIZE ? MUX_TX_MAX_SIZE : remain; 187 gdm_tty_send(gdm, 188 (void *)(buf+sent_len), 189 sending_len, 190 gdm->index, 191 gdm_tty_send_complete, 192 gdm 193 ); 194 sent_len += sending_len; 195 remain -= sending_len; 196 if (remain <= 0) 197 break; 198 } 199 200 return len; 201 } 202 203 static int gdm_tty_write_room(struct tty_struct *tty) 204 { 205 struct gdm *gdm = tty->driver_data; 206 207 if (!GDM_TTY_READY(gdm)) 208 return -ENODEV; 209 210 return WRITE_SIZE; 211 } 212 213 int register_lte_tty_device(struct tty_dev *tty_dev, struct device *device) 214 { 215 struct gdm *gdm; 216 int i; 217 int j; 218 219 for (i = 0; i < TTY_MAX_COUNT; i++) { 220 221 gdm = kmalloc(sizeof(struct gdm), GFP_KERNEL); 222 if (!gdm) 223 return -ENOMEM; 224 225 mutex_lock(&gdm_table_lock); 226 227 for (j = 0; j < GDM_TTY_MINOR; j++) { 228 if (!gdm_table[i][j]) 229 break; 230 } 231 232 if (j == GDM_TTY_MINOR) { 233 tty_dev->minor[i] = GDM_TTY_MINOR; 234 mutex_unlock(&gdm_table_lock); 235 return -EINVAL; 236 } 237 238 gdm_table[i][j] = gdm; 239 240 mutex_unlock(&gdm_table_lock); 241 242 tty_dev->minor[i] = j; 243 244 tty_port_init(&gdm->port); 245 gdm->port.ops = &gdm_port_ops; 246 gdm->index = i; 247 gdm->minor = j; 248 gdm->tty_dev = tty_dev; 249 250 tty_port_register_device(&gdm->port, gdm_driver[i], j, device); 251 } 252 253 for (i = 0; i < MAX_ISSUE_NUM; i++) 254 gdm_tty_recv(gdm, gdm_tty_recv_complete); 255 256 return 0; 257 } 258 259 void unregister_lte_tty_device(struct tty_dev *tty_dev) 260 { 261 struct gdm *gdm; 262 struct tty_struct *tty; 263 int i; 264 int j; 265 266 for (i = 0; i < TTY_MAX_COUNT; i++) { 267 268 j = tty_dev->minor[i]; 269 270 if (j >= GDM_TTY_MINOR) 271 continue; 272 273 mutex_lock(&gdm_table_lock); 274 gdm = gdm_table[i][j]; 275 mutex_unlock(&gdm_table_lock); 276 277 if (!gdm) 278 continue; 279 280 tty = tty_port_tty_get(&gdm->port); 281 if (tty) { 282 tty_vhangup(tty); 283 tty_kref_put(tty); 284 } 285 286 tty_unregister_device(gdm_driver[i], j); 287 tty_port_put(&gdm->port); 288 289 } 290 } 291 292 static const struct tty_operations gdm_tty_ops = { 293 .install = gdm_tty_install, 294 .open = gdm_tty_open, 295 .close = gdm_tty_close, 296 .cleanup = gdm_tty_cleanup, 297 .hangup = gdm_tty_hangup, 298 .write = gdm_tty_write, 299 .write_room = gdm_tty_write_room, 300 }; 301 302 int register_lte_tty_driver(void) 303 { 304 struct tty_driver *tty_driver; 305 int i; 306 int ret; 307 308 for (i = 0; i < TTY_MAX_COUNT; i++) { 309 tty_driver = alloc_tty_driver(GDM_TTY_MINOR); 310 if (!tty_driver) 311 return -ENOMEM; 312 313 tty_driver->owner = THIS_MODULE; 314 tty_driver->driver_name = DRIVER_STRING[i]; 315 tty_driver->name = DEVICE_STRING[i]; 316 tty_driver->major = GDM_TTY_MAJOR; 317 tty_driver->type = TTY_DRIVER_TYPE_SERIAL; 318 tty_driver->subtype = SERIAL_TYPE_NORMAL; 319 tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV; 320 tty_driver->init_termios = tty_std_termios; 321 tty_driver->init_termios.c_cflag = B9600 | CS8 | HUPCL | CLOCAL; 322 tty_driver->init_termios.c_lflag = ISIG | ICANON | IEXTEN; 323 tty_set_operations(tty_driver, &gdm_tty_ops); 324 325 ret = tty_register_driver(tty_driver); 326 if (ret) { 327 put_tty_driver(tty_driver); 328 return ret; 329 } 330 331 gdm_driver[i] = tty_driver; 332 } 333 334 return ret; 335 } 336 337 void unregister_lte_tty_driver(void) 338 { 339 struct tty_driver *tty_driver; 340 int i; 341 342 for (i = 0; i < TTY_MAX_COUNT; i++) { 343 tty_driver = gdm_driver[i]; 344 if (tty_driver) { 345 tty_unregister_driver(tty_driver); 346 put_tty_driver(tty_driver); 347 } 348 } 349 } 350 351