mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-05 09:26:44 +07:00
b19e2ca77e
So now for those drivers that can use neither tty_port_install nor tty_port_register_driver but still have tty_port available before tty_register_driver we use newly added tty_port_link_device. The rest of the drivers that still do not provide tty_struct <-> tty_port link will have to be converted to implement tty->ops->install. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
295 lines
6.0 KiB
C
295 lines
6.0 KiB
C
/*
|
||
* linux/arch/alpha/kernel/srmcons.c
|
||
*
|
||
* Callback based driver for SRM Console console device.
|
||
* (TTY driver and console driver)
|
||
*/
|
||
|
||
#include <linux/kernel.h>
|
||
#include <linux/init.h>
|
||
#include <linux/console.h>
|
||
#include <linux/delay.h>
|
||
#include <linux/mm.h>
|
||
#include <linux/slab.h>
|
||
#include <linux/spinlock.h>
|
||
#include <linux/timer.h>
|
||
#include <linux/tty.h>
|
||
#include <linux/tty_driver.h>
|
||
#include <linux/tty_flip.h>
|
||
|
||
#include <asm/console.h>
|
||
#include <asm/uaccess.h>
|
||
|
||
|
||
static DEFINE_SPINLOCK(srmcons_callback_lock);
|
||
static int srm_is_registered_console = 0;
|
||
|
||
/*
|
||
* The TTY driver
|
||
*/
|
||
#define MAX_SRM_CONSOLE_DEVICES 1 /* only support 1 console device */
|
||
|
||
struct srmcons_private {
|
||
struct tty_port port;
|
||
struct timer_list timer;
|
||
} srmcons_singleton;
|
||
|
||
typedef union _srmcons_result {
|
||
struct {
|
||
unsigned long c :61;
|
||
unsigned long status :3;
|
||
} bits;
|
||
long as_long;
|
||
} srmcons_result;
|
||
|
||
/* called with callback_lock held */
|
||
static int
|
||
srmcons_do_receive_chars(struct tty_struct *tty)
|
||
{
|
||
srmcons_result result;
|
||
int count = 0, loops = 0;
|
||
|
||
do {
|
||
result.as_long = callback_getc(0);
|
||
if (result.bits.status < 2) {
|
||
tty_insert_flip_char(tty, (char)result.bits.c, 0);
|
||
count++;
|
||
}
|
||
} while((result.bits.status & 1) && (++loops < 10));
|
||
|
||
if (count)
|
||
tty_schedule_flip(tty);
|
||
|
||
return count;
|
||
}
|
||
|
||
static void
|
||
srmcons_receive_chars(unsigned long data)
|
||
{
|
||
struct srmcons_private *srmconsp = (struct srmcons_private *)data;
|
||
struct tty_port *port = &srmconsp->port;
|
||
unsigned long flags;
|
||
int incr = 10;
|
||
|
||
local_irq_save(flags);
|
||
if (spin_trylock(&srmcons_callback_lock)) {
|
||
if (!srmcons_do_receive_chars(port->tty))
|
||
incr = 100;
|
||
spin_unlock(&srmcons_callback_lock);
|
||
}
|
||
|
||
spin_lock(&port->lock);
|
||
if (port->tty)
|
||
mod_timer(&srmconsp->timer, jiffies + incr);
|
||
spin_unlock(&port->lock);
|
||
|
||
local_irq_restore(flags);
|
||
}
|
||
|
||
/* called with callback_lock held */
|
||
static int
|
||
srmcons_do_write(struct tty_struct *tty, const char *buf, int count)
|
||
{
|
||
static char str_cr[1] = "\r";
|
||
long c, remaining = count;
|
||
srmcons_result result;
|
||
char *cur;
|
||
int need_cr;
|
||
|
||
for (cur = (char *)buf; remaining > 0; ) {
|
||
need_cr = 0;
|
||
/*
|
||
* Break it up into reasonable size chunks to allow a chance
|
||
* for input to get in
|
||
*/
|
||
for (c = 0; c < min_t(long, 128L, remaining) && !need_cr; c++)
|
||
if (cur[c] == '\n')
|
||
need_cr = 1;
|
||
|
||
while (c > 0) {
|
||
result.as_long = callback_puts(0, cur, c);
|
||
c -= result.bits.c;
|
||
remaining -= result.bits.c;
|
||
cur += result.bits.c;
|
||
|
||
/*
|
||
* Check for pending input iff a tty was provided
|
||
*/
|
||
if (tty)
|
||
srmcons_do_receive_chars(tty);
|
||
}
|
||
|
||
while (need_cr) {
|
||
result.as_long = callback_puts(0, str_cr, 1);
|
||
if (result.bits.c > 0)
|
||
need_cr = 0;
|
||
}
|
||
}
|
||
return count;
|
||
}
|
||
|
||
static int
|
||
srmcons_write(struct tty_struct *tty,
|
||
const unsigned char *buf, int count)
|
||
{
|
||
unsigned long flags;
|
||
|
||
spin_lock_irqsave(&srmcons_callback_lock, flags);
|
||
srmcons_do_write(tty, (const char *) buf, count);
|
||
spin_unlock_irqrestore(&srmcons_callback_lock, flags);
|
||
|
||
return count;
|
||
}
|
||
|
||
static int
|
||
srmcons_write_room(struct tty_struct *tty)
|
||
{
|
||
return 512;
|
||
}
|
||
|
||
static int
|
||
srmcons_chars_in_buffer(struct tty_struct *tty)
|
||
{
|
||
return 0;
|
||
}
|
||
|
||
static int
|
||
srmcons_open(struct tty_struct *tty, struct file *filp)
|
||
{
|
||
struct srmcons_private *srmconsp = &srmcons_singleton;
|
||
struct tty_port *port = &srmconsp->port;
|
||
unsigned long flags;
|
||
|
||
spin_lock_irqsave(&port->lock, flags);
|
||
|
||
if (!port->tty) {
|
||
tty->driver_data = srmconsp;
|
||
tty->port = port;
|
||
port->tty = tty; /* XXX proper refcounting */
|
||
mod_timer(&srmconsp->timer, jiffies + 10);
|
||
}
|
||
|
||
spin_unlock_irqrestore(&port->lock, flags);
|
||
|
||
return 0;
|
||
}
|
||
|
||
static void
|
||
srmcons_close(struct tty_struct *tty, struct file *filp)
|
||
{
|
||
struct srmcons_private *srmconsp = tty->driver_data;
|
||
struct tty_port *port = &srmconsp->port;
|
||
unsigned long flags;
|
||
|
||
spin_lock_irqsave(&port->lock, flags);
|
||
|
||
if (tty->count == 1) {
|
||
port->tty = NULL;
|
||
del_timer(&srmconsp->timer);
|
||
}
|
||
|
||
spin_unlock_irqrestore(&port->lock, flags);
|
||
}
|
||
|
||
|
||
static struct tty_driver *srmcons_driver;
|
||
|
||
static const struct tty_operations srmcons_ops = {
|
||
.open = srmcons_open,
|
||
.close = srmcons_close,
|
||
.write = srmcons_write,
|
||
.write_room = srmcons_write_room,
|
||
.chars_in_buffer= srmcons_chars_in_buffer,
|
||
};
|
||
|
||
static int __init
|
||
srmcons_init(void)
|
||
{
|
||
tty_port_init(&srmcons_singleton.port);
|
||
setup_timer(&srmcons_singleton.timer, srmcons_receive_chars,
|
||
(unsigned long)&srmcons_singleton);
|
||
if (srm_is_registered_console) {
|
||
struct tty_driver *driver;
|
||
int err;
|
||
|
||
driver = alloc_tty_driver(MAX_SRM_CONSOLE_DEVICES);
|
||
if (!driver)
|
||
return -ENOMEM;
|
||
driver->driver_name = "srm";
|
||
driver->name = "srm";
|
||
driver->major = 0; /* dynamic */
|
||
driver->minor_start = 0;
|
||
driver->type = TTY_DRIVER_TYPE_SYSTEM;
|
||
driver->subtype = SYSTEM_TYPE_SYSCONS;
|
||
driver->init_termios = tty_std_termios;
|
||
tty_set_operations(driver, &srmcons_ops);
|
||
tty_port_link_device(&srmcons_singleton.port, driver, 0);
|
||
err = tty_register_driver(driver);
|
||
if (err) {
|
||
put_tty_driver(driver);
|
||
return err;
|
||
}
|
||
srmcons_driver = driver;
|
||
}
|
||
|
||
return -ENODEV;
|
||
}
|
||
|
||
module_init(srmcons_init);
|
||
|
||
|
||
/*
|
||
* The console driver
|
||
*/
|
||
static void
|
||
srm_console_write(struct console *co, const char *s, unsigned count)
|
||
{
|
||
unsigned long flags;
|
||
|
||
spin_lock_irqsave(&srmcons_callback_lock, flags);
|
||
srmcons_do_write(NULL, s, count);
|
||
spin_unlock_irqrestore(&srmcons_callback_lock, flags);
|
||
}
|
||
|
||
static struct tty_driver *
|
||
srm_console_device(struct console *co, int *index)
|
||
{
|
||
*index = co->index;
|
||
return srmcons_driver;
|
||
}
|
||
|
||
static int
|
||
srm_console_setup(struct console *co, char *options)
|
||
{
|
||
return 0;
|
||
}
|
||
|
||
static struct console srmcons = {
|
||
.name = "srm",
|
||
.write = srm_console_write,
|
||
.device = srm_console_device,
|
||
.setup = srm_console_setup,
|
||
.flags = CON_PRINTBUFFER | CON_BOOT,
|
||
.index = -1,
|
||
};
|
||
|
||
void __init
|
||
register_srm_console(void)
|
||
{
|
||
if (!srm_is_registered_console) {
|
||
callback_open_console();
|
||
register_console(&srmcons);
|
||
srm_is_registered_console = 1;
|
||
}
|
||
}
|
||
|
||
void __init
|
||
unregister_srm_console(void)
|
||
{
|
||
if (srm_is_registered_console) {
|
||
callback_close_console();
|
||
unregister_console(&srmcons);
|
||
srm_is_registered_console = 0;
|
||
}
|
||
}
|