diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/parisc/kernel/pdc_cons.c | 141 |
1 files changed, 134 insertions, 7 deletions
diff --git a/arch/parisc/kernel/pdc_cons.c b/arch/parisc/kernel/pdc_cons.c index 1ff366cb9685..66d1f17fdb94 100644 --- a/arch/parisc/kernel/pdc_cons.c +++ b/arch/parisc/kernel/pdc_cons.c @@ -12,6 +12,7 @@ * Copyright (C) 2001 Helge Deller <deller at parisc-linux.org> * Copyright (C) 2001 Thomas Bogendoerfer <tsbogend at parisc-linux.org> * Copyright (C) 2002 Randolph Chung <tausq with parisc-linux.org> + * Copyright (C) 2010 Guy Martin <gmsoft at tuxicoman.be> * * * This program is free software; you can redistribute it and/or modify @@ -31,12 +32,11 @@ /* * The PDC console is a simple console, which can be used for debugging - * boot related problems on HP PA-RISC machines. + * boot related problems on HP PA-RISC machines. It is also useful when no + * other console works. * * This code uses the ROM (=PDC) based functions to read and write characters * from and to PDC's boot path. - * Since all character read from that path must be polled, this code never - * can or will be a fully functional linux console. */ /* Define EARLY_BOOTUP_DEBUG to debug kernel related boot problems. @@ -53,6 +53,7 @@ #include <asm/pdc.h> /* for iodc_call() proto and friends */ static DEFINE_SPINLOCK(pdc_console_lock); +static struct console pdc_cons; static void pdc_console_write(struct console *co, const char *s, unsigned count) { @@ -85,12 +86,138 @@ static int pdc_console_setup(struct console *co, char *options) #if defined(CONFIG_PDC_CONSOLE) #include <linux/vt_kern.h> +#include <linux/tty_flip.h> + +#define PDC_CONS_POLL_DELAY (30 * HZ / 1000) + +static struct timer_list pdc_console_timer; + +extern struct console * console_drivers; + +static int pdc_console_tty_open(struct tty_struct *tty, struct file *filp) +{ + + mod_timer(&pdc_console_timer, jiffies + PDC_CONS_POLL_DELAY); + + return 0; +} + +static void pdc_console_tty_close(struct tty_struct *tty, struct file *filp) +{ + if (!tty->count) + del_timer(&pdc_console_timer); +} + +static int pdc_console_tty_write(struct tty_struct *tty, const unsigned char *buf, int count) +{ + pdc_console_write(NULL, buf, count); + return count; +} + +static int pdc_console_tty_write_room(struct tty_struct *tty) +{ + return 32768; /* no limit, no buffer used */ +} + +static int pdc_console_tty_chars_in_buffer(struct tty_struct *tty) +{ + return 0; /* no buffer */ +} + +static struct tty_driver *pdc_console_tty_driver; + +static const struct tty_operations pdc_console_tty_ops = { + .open = pdc_console_tty_open, + .close = pdc_console_tty_close, + .write = pdc_console_tty_write, + .write_room = pdc_console_tty_write_room, + .chars_in_buffer = pdc_console_tty_chars_in_buffer, +}; + +static void pdc_console_poll(unsigned long unused) +{ + + int data, count = 0; + + struct tty_struct *tty = pdc_console_tty_driver->ttys[0]; + + if (!tty) + return; + + while (1) { + data = pdc_console_poll_key(NULL); + if (data == -1) + break; + tty_insert_flip_char(tty, data & 0xFF, TTY_NORMAL); + count ++; + } + + if (count) + tty_flip_buffer_push(tty); + + if (tty->count && (pdc_cons.flags & CON_ENABLED)) + mod_timer(&pdc_console_timer, jiffies + PDC_CONS_POLL_DELAY); +} + +static int __init pdc_console_tty_driver_init(void) +{ + + int err; + struct tty_driver *drv; + + /* Check if the console driver is still registered. + * It is unregistered if the pdc console was not selected as the + * primary console. */ + + struct console *tmp = console_drivers; + + for (tmp = console_drivers; tmp; tmp = tmp->next) + if (tmp == &pdc_cons) + break; + + if (!tmp) { + printk(KERN_INFO "PDC console driver not registered anymore, not creating %s\n", pdc_cons.name); + return -ENODEV; + } + + printk(KERN_INFO "The PDC console driver is still registered, removing CON_BOOT flag\n"); + pdc_cons.flags &= ~CON_BOOT; + + drv = alloc_tty_driver(1); + + if (!drv) + return -ENOMEM; + + drv->driver_name = "pdc_cons"; + drv->name = "ttyB"; + drv->major = MUX_MAJOR; + drv->minor_start = 0; + drv->type = TTY_DRIVER_TYPE_SYSTEM; + drv->init_termios = tty_std_termios; + drv->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_RESET_TERMIOS; + tty_set_operations(drv, &pdc_console_tty_ops); + + err = tty_register_driver(drv); + if (err) { + printk(KERN_ERR "Unable to register the PDC console TTY driver\n"); + return err; + } + + pdc_console_tty_driver = drv; + + /* No need to initialize the pdc_console_timer if tty isn't allocated */ + init_timer(&pdc_console_timer); + pdc_console_timer.function = pdc_console_poll; + + return 0; +} + +module_init(pdc_console_tty_driver_init); static struct tty_driver * pdc_console_device (struct console *c, int *index) { - extern struct tty_driver console_driver; - *index = c->index ? c->index-1 : fg_console; - return &console_driver; + *index = c->index; + return pdc_console_tty_driver; } #else #define pdc_console_device NULL @@ -101,7 +228,7 @@ static struct console pdc_cons = { .write = pdc_console_write, .device = pdc_console_device, .setup = pdc_console_setup, - .flags = CON_BOOT | CON_PRINTBUFFER | CON_ENABLED, + .flags = CON_BOOT | CON_PRINTBUFFER, .index = -1, }; |