android_kernel_motorola_sm6225/drivers/s390/char/sclp_con.c
Heiko Carstens 095761d28a [S390] sclp_tty: remove ioctl interface.
After all we came to the conclusion that this interface doesn't make any
sense. Besides that the ioctl number used was never registered, the header
file isn't exported, and we doubt there is even a single user.
So remove this interface, since it eases maintenance.

Cc: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-07-14 10:02:25 +02:00

248 lines
6.4 KiB
C

/*
* drivers/s390/char/sclp_con.c
* SCLP line mode console driver
*
* S390 version
* Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Martin Peschke <mpeschke@de.ibm.com>
* Martin Schwidefsky <schwidefsky@de.ibm.com>
*/
#include <linux/kmod.h>
#include <linux/console.h>
#include <linux/init.h>
#include <linux/timer.h>
#include <linux/jiffies.h>
#include <linux/bootmem.h>
#include <linux/termios.h>
#include <linux/err.h>
#include "sclp.h"
#include "sclp_rw.h"
#include "sclp_tty.h"
#define sclp_console_major 4 /* TTYAUX_MAJOR */
#define sclp_console_minor 64
#define sclp_console_name "ttyS"
/* Lock to guard over changes to global variables */
static spinlock_t sclp_con_lock;
/* List of free pages that can be used for console output buffering */
static struct list_head sclp_con_pages;
/* List of full struct sclp_buffer structures ready for output */
static struct list_head sclp_con_outqueue;
/* Counter how many buffers are emitted (max 1) and how many */
/* are on the output queue. */
static int sclp_con_buffer_count;
/* Pointer to current console buffer */
static struct sclp_buffer *sclp_conbuf;
/* Timer for delayed output of console messages */
static struct timer_list sclp_con_timer;
/* Output format for console messages */
static unsigned short sclp_con_columns;
static unsigned short sclp_con_width_htab;
static void
sclp_conbuf_callback(struct sclp_buffer *buffer, int rc)
{
unsigned long flags;
void *page;
do {
page = sclp_unmake_buffer(buffer);
spin_lock_irqsave(&sclp_con_lock, flags);
/* Remove buffer from outqueue */
list_del(&buffer->list);
sclp_con_buffer_count--;
list_add_tail((struct list_head *) page, &sclp_con_pages);
/* Check if there is a pending buffer on the out queue. */
buffer = NULL;
if (!list_empty(&sclp_con_outqueue))
buffer = list_entry(sclp_con_outqueue.next,
struct sclp_buffer, list);
spin_unlock_irqrestore(&sclp_con_lock, flags);
} while (buffer && sclp_emit_buffer(buffer, sclp_conbuf_callback));
}
static void
sclp_conbuf_emit(void)
{
struct sclp_buffer* buffer;
unsigned long flags;
int count;
int rc;
spin_lock_irqsave(&sclp_con_lock, flags);
buffer = sclp_conbuf;
sclp_conbuf = NULL;
if (buffer == NULL) {
spin_unlock_irqrestore(&sclp_con_lock, flags);
return;
}
list_add_tail(&buffer->list, &sclp_con_outqueue);
count = sclp_con_buffer_count++;
spin_unlock_irqrestore(&sclp_con_lock, flags);
if (count)
return;
rc = sclp_emit_buffer(buffer, sclp_conbuf_callback);
if (rc)
sclp_conbuf_callback(buffer, rc);
}
/*
* When this routine is called from the timer then we flush the
* temporary write buffer without further waiting on a final new line.
*/
static void
sclp_console_timeout(unsigned long data)
{
sclp_conbuf_emit();
}
/*
* Writes the given message to S390 system console
*/
static void
sclp_console_write(struct console *console, const char *message,
unsigned int count)
{
unsigned long flags;
void *page;
int written;
if (count == 0)
return;
spin_lock_irqsave(&sclp_con_lock, flags);
/*
* process escape characters, write message into buffer,
* send buffer to SCLP
*/
do {
/* make sure we have a console output buffer */
if (sclp_conbuf == NULL) {
while (list_empty(&sclp_con_pages)) {
spin_unlock_irqrestore(&sclp_con_lock, flags);
sclp_sync_wait();
spin_lock_irqsave(&sclp_con_lock, flags);
}
page = sclp_con_pages.next;
list_del((struct list_head *) page);
sclp_conbuf = sclp_make_buffer(page, sclp_con_columns,
sclp_con_width_htab);
}
/* try to write the string to the current output buffer */
written = sclp_write(sclp_conbuf, (const unsigned char *)
message, count);
if (written == count)
break;
/*
* Not all characters could be written to the current
* output buffer. Emit the buffer, create a new buffer
* and then output the rest of the string.
*/
spin_unlock_irqrestore(&sclp_con_lock, flags);
sclp_conbuf_emit();
spin_lock_irqsave(&sclp_con_lock, flags);
message += written;
count -= written;
} while (count > 0);
/* Setup timer to output current console buffer after 1/10 second */
if (sclp_conbuf != NULL && sclp_chars_in_buffer(sclp_conbuf) != 0 &&
!timer_pending(&sclp_con_timer)) {
init_timer(&sclp_con_timer);
sclp_con_timer.function = sclp_console_timeout;
sclp_con_timer.data = 0UL;
sclp_con_timer.expires = jiffies + HZ/10;
add_timer(&sclp_con_timer);
}
spin_unlock_irqrestore(&sclp_con_lock, flags);
}
static struct tty_driver *
sclp_console_device(struct console *c, int *index)
{
*index = c->index;
return sclp_tty_driver;
}
/*
* This routine is called from panic when the kernel
* is going to give up. We have to make sure that all buffers
* will be flushed to the SCLP.
*/
static void
sclp_console_unblank(void)
{
unsigned long flags;
sclp_conbuf_emit();
spin_lock_irqsave(&sclp_con_lock, flags);
if (timer_pending(&sclp_con_timer))
del_timer(&sclp_con_timer);
while (sclp_con_buffer_count > 0) {
spin_unlock_irqrestore(&sclp_con_lock, flags);
sclp_sync_wait();
spin_lock_irqsave(&sclp_con_lock, flags);
}
spin_unlock_irqrestore(&sclp_con_lock, flags);
}
/*
* used to register the SCLP console to the kernel and to
* give printk necessary information
*/
static struct console sclp_console =
{
.name = sclp_console_name,
.write = sclp_console_write,
.device = sclp_console_device,
.unblank = sclp_console_unblank,
.flags = CON_PRINTBUFFER,
.index = 0 /* ttyS0 */
};
/*
* called by console_init() in drivers/char/tty_io.c at boot-time.
*/
static int __init
sclp_console_init(void)
{
void *page;
int i;
int rc;
if (!CONSOLE_IS_SCLP)
return 0;
rc = sclp_rw_init();
if (rc)
return rc;
/* Allocate pages for output buffering */
INIT_LIST_HEAD(&sclp_con_pages);
for (i = 0; i < MAX_CONSOLE_PAGES; i++) {
page = alloc_bootmem_low_pages(PAGE_SIZE);
list_add_tail((struct list_head *) page, &sclp_con_pages);
}
INIT_LIST_HEAD(&sclp_con_outqueue);
spin_lock_init(&sclp_con_lock);
sclp_con_buffer_count = 0;
sclp_conbuf = NULL;
init_timer(&sclp_con_timer);
/* Set output format */
if (MACHINE_IS_VM)
/*
* save 4 characters for the CPU number
* written at start of each line by VM/CP
*/
sclp_con_columns = 76;
else
sclp_con_columns = 80;
sclp_con_width_htab = 8;
/* enable printk-access to this driver */
register_console(&sclp_console);
return 0;
}
console_initcall(sclp_console_init);