diff options
| -rw-r--r-- | drivers/tty/Kconfig | 14 | ||||
| -rw-r--r-- | drivers/tty/Makefile | 3 | ||||
| -rw-r--r-- | drivers/tty/ttynull.c | 18 | ||||
| -rw-r--r-- | include/linux/console.h | 3 | ||||
| -rw-r--r-- | init/main.c | 10 |
5 files changed, 18 insertions, 30 deletions
diff --git a/drivers/tty/Kconfig b/drivers/tty/Kconfig index 47a6e42f0d04..e15cd6b5bb99 100644 --- a/drivers/tty/Kconfig +++ b/drivers/tty/Kconfig @@ -401,6 +401,20 @@ config MIPS_EJTAG_FDC_KGDB_CHAN help FDC channel number to use for KGDB. +config NULL_TTY + tristate "NULL TTY driver" + help + Say Y here if you want a NULL TTY which simply discards messages. + + This is useful to allow userspace applications which expect a console + device to work without modifications even when no console is + available or desired. + + In order to use this driver, you should redirect the console to this + TTY, or boot the kernel with console=ttynull. + + If unsure, say N. + config TRACE_ROUTER tristate "Trace data router for MIPI P1149.7 cJTAG standard" depends on TRACE_SINK diff --git a/drivers/tty/Makefile b/drivers/tty/Makefile index 3c1c5a9240a7..b3ccae932660 100644 --- a/drivers/tty/Makefile +++ b/drivers/tty/Makefile @@ -2,7 +2,7 @@ obj-$(CONFIG_TTY) += tty_io.o n_tty.o tty_ioctl.o tty_ldisc.o \ tty_buffer.o tty_port.o tty_mutex.o \ tty_ldsem.o tty_baudrate.o tty_jobctrl.o \ - n_null.o ttynull.o + n_null.o obj-$(CONFIG_LEGACY_PTYS) += pty.o obj-$(CONFIG_UNIX98_PTYS) += pty.o obj-$(CONFIG_AUDIT) += tty_audit.o @@ -25,6 +25,7 @@ obj-$(CONFIG_ISI) += isicom.o obj-$(CONFIG_MOXA_INTELLIO) += moxa.o obj-$(CONFIG_MOXA_SMARTIO) += mxser.o obj-$(CONFIG_NOZOMI) += nozomi.o +obj-$(CONFIG_NULL_TTY) += ttynull.o obj-$(CONFIG_ROCKETPORT) += rocket.o obj-$(CONFIG_SYNCLINK_GT) += synclink_gt.o obj-$(CONFIG_PPC_EPAPR_HV_BYTECHAN) += ehv_bytechan.o diff --git a/drivers/tty/ttynull.c b/drivers/tty/ttynull.c index eced70ec54e1..17f05b7eb6d3 100644 --- a/drivers/tty/ttynull.c +++ b/drivers/tty/ttynull.c @@ -2,13 +2,6 @@ /* * Copyright (C) 2019 Axis Communications AB * - * The console is useful for userspace applications which expect a console - * device to work without modifications even when no console is available - * or desired. - * - * In order to use this driver, you should redirect the console to this - * TTY, or boot the kernel with console=ttynull. - * * Based on ttyprintk.c: * Copyright (C) 2010 Samo Pogacnik */ @@ -66,17 +59,6 @@ static struct console ttynull_console = { .device = ttynull_device, }; -void __init register_ttynull_console(void) -{ - if (!ttynull_driver) - return; - - if (add_preferred_console(ttynull_console.name, 0, NULL)) - return; - - register_console(&ttynull_console); -} - static int __init ttynull_init(void) { struct tty_driver *driver; diff --git a/include/linux/console.h b/include/linux/console.h index dbe78e8e2602..20874db50bc8 100644 --- a/include/linux/console.h +++ b/include/linux/console.h @@ -186,12 +186,9 @@ extern int braille_register_console(struct console *, int index, extern int braille_unregister_console(struct console *); #ifdef CONFIG_TTY extern void console_sysfs_notify(void); -extern void register_ttynull_console(void); #else static inline void console_sysfs_notify(void) { } -static inline void register_ttynull_console(void) -{ } #endif extern bool console_suspend_enabled; diff --git a/init/main.c b/init/main.c index 421640fca375..c68d784376ca 100644 --- a/init/main.c +++ b/init/main.c @@ -1480,14 +1480,8 @@ void __init console_on_rootfs(void) struct file *file = filp_open("/dev/console", O_RDWR, 0); if (IS_ERR(file)) { - pr_err("Warning: unable to open an initial console. Fallback to ttynull.\n"); - register_ttynull_console(); - - file = filp_open("/dev/console", O_RDWR, 0); - if (IS_ERR(file)) { - pr_err("Warning: Failed to add ttynull console. No stdin, stdout, and stderr for the init process!\n"); - return; - } + pr_err("Warning: unable to open an initial console.\n"); + return; } init_dup(file); init_dup(file); |