Chris Zankel | 7282bee | 2005-06-23 22:01:33 -0700 | [diff] [blame] | 1 | /* |
| 2 | * arch/xtensa/platform-iss/console.c |
| 3 | * |
| 4 | * This file is subject to the terms and conditions of the GNU General Public |
| 5 | * License. See the file "COPYING" in the main directory of this archive |
| 6 | * for more details. |
| 7 | * |
| 8 | * Copyright (C) 2001-2005 Tensilica Inc. |
| 9 | * Authors Christian Zankel, Joe Taylor |
| 10 | */ |
| 11 | |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/config.h> |
| 14 | #include <linux/kernel.h> |
| 15 | #include <linux/sched.h> |
| 16 | #include <linux/console.h> |
| 17 | #include <linux/init.h> |
| 18 | #include <linux/slab.h> |
| 19 | #include <linux/mm.h> |
| 20 | #include <linux/major.h> |
| 21 | #include <linux/param.h> |
| 22 | #include <linux/serial.h> |
| 23 | #include <linux/serialP.h> |
| 24 | #include <linux/console.h> |
| 25 | |
| 26 | #include <asm/uaccess.h> |
| 27 | #include <asm/irq.h> |
| 28 | |
| 29 | #include <xtensa/simcall.h> |
| 30 | |
| 31 | #include <linux/tty.h> |
| 32 | #include <linux/tty_flip.h> |
| 33 | |
| 34 | #ifdef SERIAL_INLINE |
| 35 | #define _INLINE_ inline |
| 36 | #endif |
| 37 | |
| 38 | #define SERIAL_MAX_NUM_LINES 1 |
| 39 | #define SERIAL_TIMER_VALUE (20 * HZ) |
| 40 | |
| 41 | static struct tty_driver *serial_driver; |
| 42 | static struct timer_list serial_timer; |
| 43 | |
| 44 | static DEFINE_SPINLOCK(timer_lock); |
| 45 | |
| 46 | int errno; |
| 47 | |
| 48 | static int __simc (int a, int b, int c, int d, int e, int f) |
| 49 | { |
| 50 | int ret; |
| 51 | __asm__ __volatile__ ("simcall\n" |
| 52 | "mov %0, a2\n" |
| 53 | "mov %1, a3\n" : "=a" (ret), "=a" (errno) |
| 54 | : : "a2", "a3"); |
| 55 | return ret; |
| 56 | } |
| 57 | |
| 58 | static char *serial_version = "0.1"; |
| 59 | static char *serial_name = "ISS serial driver"; |
| 60 | |
| 61 | /* |
| 62 | * This routine is called whenever a serial port is opened. It |
| 63 | * enables interrupts for a serial port, linking in its async structure into |
| 64 | * the IRQ chain. It also performs the serial-specific |
| 65 | * initialization for the tty structure. |
| 66 | */ |
| 67 | |
| 68 | static void rs_poll(unsigned long); |
| 69 | |
| 70 | static int rs_open(struct tty_struct *tty, struct file * filp) |
| 71 | { |
| 72 | int line = tty->index; |
| 73 | |
| 74 | if ((line < 0) || (line >= SERIAL_MAX_NUM_LINES)) |
| 75 | return -ENODEV; |
| 76 | |
| 77 | spin_lock(&timer_lock); |
| 78 | |
| 79 | if (tty->count == 1) { |
| 80 | init_timer(&serial_timer); |
| 81 | serial_timer.data = (unsigned long) tty; |
| 82 | serial_timer.function = rs_poll; |
| 83 | mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE); |
| 84 | } |
| 85 | spin_unlock(&timer_lock); |
| 86 | |
| 87 | return 0; |
| 88 | } |
| 89 | |
| 90 | |
| 91 | /* |
| 92 | * ------------------------------------------------------------ |
| 93 | * iss_serial_close() |
| 94 | * |
| 95 | * This routine is called when the serial port gets closed. First, we |
| 96 | * wait for the last remaining data to be sent. Then, we unlink its |
| 97 | * async structure from the interrupt chain if necessary, and we free |
| 98 | * that IRQ if nothing is left in the chain. |
| 99 | * ------------------------------------------------------------ |
| 100 | */ |
| 101 | static void rs_close(struct tty_struct *tty, struct file * filp) |
| 102 | { |
| 103 | spin_lock(&timer_lock); |
| 104 | if (tty->count == 1) |
| 105 | del_timer_sync(&serial_timer); |
| 106 | spin_unlock(&timer_lock); |
| 107 | } |
| 108 | |
| 109 | |
| 110 | static int rs_write(struct tty_struct * tty, |
| 111 | const unsigned char *buf, int count) |
| 112 | { |
| 113 | /* see drivers/char/serialX.c to reference original version */ |
| 114 | |
| 115 | __simc (SYS_write, 1, (unsigned long)buf, count, 0, 0); |
| 116 | return count; |
| 117 | } |
| 118 | |
| 119 | static void rs_poll(unsigned long priv) |
| 120 | { |
| 121 | struct tty_struct* tty = (struct tty_struct*) priv; |
| 122 | |
| 123 | struct timeval tv = { .tv_sec = 0, .tv_usec = 0 }; |
| 124 | int i = 0; |
| 125 | unsigned char c; |
| 126 | |
| 127 | spin_lock(&timer_lock); |
| 128 | |
| 129 | while (__simc(SYS_select_one, 0, XTISS_SELECT_ONE_READ, (int)&tv,0,0)){ |
| 130 | __simc (SYS_read, 0, (unsigned long)&c, 1, 0, 0); |
Alan Cox | 8145916 | 2006-02-03 03:04:08 -0800 | [diff] [blame^] | 131 | tty_insert_flip_char(tty, c, TTY_NORMAL); |
Chris Zankel | 7282bee | 2005-06-23 22:01:33 -0700 | [diff] [blame] | 132 | i++; |
| 133 | } |
| 134 | |
| 135 | if (i) |
| 136 | tty_flip_buffer_push(tty); |
| 137 | |
| 138 | |
| 139 | mod_timer(&serial_timer, jiffies + SERIAL_TIMER_VALUE); |
| 140 | spin_unlock(&timer_lock); |
| 141 | } |
| 142 | |
| 143 | |
| 144 | static void rs_put_char(struct tty_struct *tty, unsigned char ch) |
| 145 | { |
| 146 | char buf[2]; |
| 147 | |
| 148 | if (!tty) |
| 149 | return; |
| 150 | |
| 151 | buf[0] = ch; |
| 152 | buf[1] = '\0'; /* Is this NULL necessary? */ |
| 153 | __simc (SYS_write, 1, (unsigned long) buf, 1, 0, 0); |
| 154 | } |
| 155 | |
| 156 | static void rs_flush_chars(struct tty_struct *tty) |
| 157 | { |
| 158 | } |
| 159 | |
| 160 | static int rs_write_room(struct tty_struct *tty) |
| 161 | { |
| 162 | /* Let's say iss can always accept 2K characters.. */ |
| 163 | return 2 * 1024; |
| 164 | } |
| 165 | |
| 166 | static int rs_chars_in_buffer(struct tty_struct *tty) |
| 167 | { |
| 168 | /* the iss doesn't buffer characters */ |
| 169 | return 0; |
| 170 | } |
| 171 | |
| 172 | static void rs_hangup(struct tty_struct *tty) |
| 173 | { |
| 174 | /* Stub, once again.. */ |
| 175 | } |
| 176 | |
| 177 | static void rs_wait_until_sent(struct tty_struct *tty, int timeout) |
| 178 | { |
| 179 | /* Stub, once again.. */ |
| 180 | } |
| 181 | |
| 182 | static int rs_read_proc(char *page, char **start, off_t off, int count, |
| 183 | int *eof, void *data) |
| 184 | { |
| 185 | int len = 0; |
| 186 | off_t begin = 0; |
| 187 | |
| 188 | len += sprintf(page, "serinfo:1.0 driver:%s\n", serial_version); |
| 189 | *eof = 1; |
| 190 | |
| 191 | if (off >= len + begin) |
| 192 | return 0; |
| 193 | |
| 194 | *start = page + (off - begin); |
| 195 | return ((count < begin + len - off) ? count : begin + len - off); |
| 196 | } |
| 197 | |
| 198 | |
Chris Zankel | 7282bee | 2005-06-23 22:01:33 -0700 | [diff] [blame] | 199 | static struct tty_operations serial_ops = { |
| 200 | .open = rs_open, |
| 201 | .close = rs_close, |
| 202 | .write = rs_write, |
| 203 | .put_char = rs_put_char, |
| 204 | .flush_chars = rs_flush_chars, |
| 205 | .write_room = rs_write_room, |
| 206 | .chars_in_buffer = rs_chars_in_buffer, |
| 207 | .hangup = rs_hangup, |
| 208 | .wait_until_sent = rs_wait_until_sent, |
| 209 | .read_proc = rs_read_proc |
| 210 | }; |
| 211 | |
| 212 | int __init rs_init(void) |
| 213 | { |
| 214 | serial_driver = alloc_tty_driver(1); |
| 215 | |
| 216 | printk ("%s %s\n", serial_name, serial_version); |
| 217 | |
| 218 | /* Initialize the tty_driver structure */ |
| 219 | |
| 220 | serial_driver->owner = THIS_MODULE; |
| 221 | serial_driver->driver_name = "iss_serial"; |
| 222 | serial_driver->name = "ttyS"; |
| 223 | serial_driver->major = TTY_MAJOR; |
| 224 | serial_driver->minor_start = 64; |
| 225 | serial_driver->type = TTY_DRIVER_TYPE_SERIAL; |
| 226 | serial_driver->subtype = SERIAL_TYPE_NORMAL; |
| 227 | serial_driver->init_termios = tty_std_termios; |
| 228 | serial_driver->init_termios.c_cflag = |
| 229 | B9600 | CS8 | CREAD | HUPCL | CLOCAL; |
| 230 | serial_driver->flags = TTY_DRIVER_REAL_RAW; |
| 231 | |
| 232 | tty_set_operations(serial_driver, &serial_ops); |
| 233 | |
| 234 | if (tty_register_driver(serial_driver)) |
| 235 | panic("Couldn't register serial driver\n"); |
| 236 | return 0; |
| 237 | } |
| 238 | |
| 239 | |
| 240 | static __exit void rs_exit(void) |
| 241 | { |
| 242 | int error; |
| 243 | |
| 244 | if ((error = tty_unregister_driver(serial_driver))) |
| 245 | printk("ISS_SERIAL: failed to unregister serial driver (%d)\n", |
| 246 | error); |
| 247 | put_tty_driver(serial_driver); |
| 248 | } |
| 249 | |
| 250 | |
| 251 | /* We use `late_initcall' instead of just `__initcall' as a workaround for |
| 252 | * the fact that (1) simcons_tty_init can't be called before tty_init, |
| 253 | * (2) tty_init is called via `module_init', (3) if statically linked, |
| 254 | * module_init == device_init, and (4) there's no ordering of init lists. |
| 255 | * We can do this easily because simcons is always statically linked, but |
| 256 | * other tty drivers that depend on tty_init and which must use |
| 257 | * `module_init' to declare their init routines are likely to be broken. |
| 258 | */ |
| 259 | |
| 260 | late_initcall(rs_init); |
| 261 | |
| 262 | |
| 263 | #ifdef CONFIG_SERIAL_CONSOLE |
| 264 | |
| 265 | static void iss_console_write(struct console *co, const char *s, unsigned count) |
| 266 | { |
| 267 | int len = strlen(s); |
| 268 | |
| 269 | if (s != 0 && *s != 0) |
| 270 | __simc (SYS_write, 1, (unsigned long)s, |
| 271 | count < len ? count : len,0,0); |
| 272 | } |
| 273 | |
| 274 | static struct tty_driver* iss_console_device(struct console *c, int *index) |
| 275 | { |
| 276 | *index = c->index; |
| 277 | return serial_driver; |
| 278 | } |
| 279 | |
| 280 | |
| 281 | static struct console sercons = { |
| 282 | .name = "ttyS", |
| 283 | .write = iss_console_write, |
| 284 | .device = iss_console_device, |
| 285 | .flags = CON_PRINTBUFFER, |
| 286 | .index = -1 |
| 287 | }; |
| 288 | |
| 289 | static int __init iss_console_init(void) |
| 290 | { |
| 291 | register_console(&sercons); |
| 292 | return 0; |
| 293 | } |
| 294 | |
| 295 | console_initcall(iss_console_init); |
| 296 | |
| 297 | #endif /* CONFIG_SERIAL_CONSOLE */ |
| 298 | |