diff options
| author | Joe Millenbach <jmillenbach@gmail.com> | 2013-01-17 22:44:22 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-01-18 16:15:27 -0800 |
| commit | 4f73bc4dd3e8563ef4109f293a092820dff66d92 (patch) | |
| tree | 8ebd5d01abaceb70da1932db1a5e7219630b0fd3 /drivers/tty | |
| parent | a1bf9584429d61b7096f93ae09325e1ba538e9e8 (diff) | |
tty: Added a CONFIG_TTY option to allow removal of TTY
The option allows you to remove TTY and compile without errors. This
saves space on systems that won't support TTY interfaces anyway.
bloat-o-meter output is below.
The bulk of this patch consists of Kconfig changes adding "depends on
TTY" to various serial devices and similar drivers that require the TTY
layer. Ideally, these dependencies would occur on a common intermediate
symbol such as SERIO, but most drivers "select SERIO" rather than
"depends on SERIO", and "select" does not respect dependencies.
bloat-o-meter output comparing our previous minimal to new minimal by
removing TTY. The list is filtered to not show removed entries with awk
'$3 != "-"' as the list was very long.
add/remove: 0/226 grow/shrink: 2/14 up/down: 6/-35356 (-35350)
function old new delta
chr_dev_init 166 170 +4
allow_signal 80 82 +2
static.__warned 143 142 -1
disallow_signal 63 62 -1
__set_special_pids 95 94 -1
unregister_console 126 121 -5
start_kernel 546 541 -5
register_console 593 588 -5
copy_from_user 45 40 -5
sys_setsid 128 120 -8
sys_vhangup 32 19 -13
do_exit 1543 1526 -17
bitmap_zero 60 40 -20
arch_local_irq_save 137 117 -20
release_task 674 652 -22
static.spin_unlock_irqrestore 308 260 -48
Signed-off-by: Joe Millenbach <jmillenbach@gmail.com>
Reviewed-by: Jamey Sharp <jamey@minilop.net>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/Kconfig | 13 | ||||
| -rw-r--r-- | drivers/tty/Makefile | 2 | ||||
| -rw-r--r-- | drivers/tty/hvc/Kconfig | 3 | ||||
| -rw-r--r-- | drivers/tty/serial/Kconfig | 4 |
4 files changed, 21 insertions, 1 deletions
diff --git a/drivers/tty/Kconfig b/drivers/tty/Kconfig index 0ecf22b6a38e..a79fd8ebd56e 100644 --- a/drivers/tty/Kconfig +++ b/drivers/tty/Kconfig @@ -1,3 +1,14 @@ +config TTY + bool "Enable TTY" if EXPERT + default y + ---help--- + Allows you to remove TTY support which can save space, and + blocks features that require TTY from inclusion in the kernel. + TTY is required for any text terminals or serial port + communication. Most users should leave this enabled. + +if TTY + config VT bool "Virtual terminal" if EXPERT depends on !S390 && !UML @@ -388,3 +399,5 @@ config PPC_EARLY_DEBUG_EHV_BC_HANDLE If the number you specify is not a valid byte channel handle, then there simply will be no early console output. This is true also if you don't boot under a hypervisor at all. + +endif # TTY diff --git a/drivers/tty/Makefile b/drivers/tty/Makefile index 2953059530e4..df5663d0d55e 100644 --- a/drivers/tty/Makefile +++ b/drivers/tty/Makefile @@ -1,4 +1,4 @@ -obj-y += tty_io.o n_tty.o tty_ioctl.o tty_ldisc.o \ +obj-$(CONFIG_TTY) += tty_io.o n_tty.o tty_ioctl.o tty_ldisc.o \ tty_buffer.o tty_port.o tty_mutex.o obj-$(CONFIG_LEGACY_PTYS) += pty.o obj-$(CONFIG_UNIX98_PTYS) += pty.o diff --git a/drivers/tty/hvc/Kconfig b/drivers/tty/hvc/Kconfig index f47b734c6a7a..8902f9b4df71 100644 --- a/drivers/tty/hvc/Kconfig +++ b/drivers/tty/hvc/Kconfig @@ -1,3 +1,5 @@ +if TTY + config HVC_DRIVER bool help @@ -119,3 +121,4 @@ config HVCS which will also be compiled when this driver is built as a module. +endif # TTY diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index 2dc429357fe3..e9aeccdfbe35 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -2,6 +2,8 @@ # Serial device configuration # +if TTY + menu "Serial drivers" depends on HAS_IOMEM @@ -1483,3 +1485,5 @@ config SERIAL_RP2_NR_UARTS need to be increased. endmenu + +endif # TTY |