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path: root/drivers/tty/hvc/Kconfig
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2013-01-18tty: Added a CONFIG_TTY option to allow removal of TTYJoe Millenbach
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>
2012-09-18tty/serial: remove CONFIG_EXPERIMENTAL dependenciesGreg Kroah-Hartman
As discussed at the kernel summit this year, CONFIG_EXPERIMENTAL means nothing, so let's get rid of it. Cc: Kees Cook <keescook@chromium.org> Cc: Alan Cox <alan@linux.intel.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-22Merge tag 'stable/for-linus-3.4-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull xen updates from Konrad Rzeszutek Wilk: "which has three neat features: - PV multiconsole support, so that there can be hvc1, hvc2, etc; This can be used in HVM and in PV mode. - P-state and C-state power management driver that uploads said power management data to the hypervisor. It also inhibits cpufreq scaling drivers to load so that only the hypervisor can make power management decisions - fixing a weird perf bug. There is one thing in the Kconfig that you won't like: "default y if (X86_ACPI_CPUFREQ = y || X86_POWERNOW_K8 = y)" (note, that it all depends on CONFIG_XEN which depends on CONFIG_PARAVIRT which by default is off). I've a fix to convert that boolean expression into "default m" which I am going to post after the cpufreq git pull - as the two patches to make this work depend on a fix in Dave Jones's tree. - Function Level Reset (FLR) support in the Xen PCI backend. Fixes: - Kconfig dependencies for Xen PV keyboard and video - Compile warnings and constify fixes - Change over to use percpu_xxx instead of this_cpu_xxx" Fix up trivial conflicts in drivers/tty/hvc/hvc_xen.c due to changes to a removed commit. * tag 'stable/for-linus-3.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen kconfig: relax INPUT_XEN_KBDDEV_FRONTEND deps xen/acpi-processor: C and P-state driver that uploads said data to hypervisor. xen: constify all instances of "struct attribute_group" xen/xenbus: ignore console/0 hvc_xen: introduce HVC_XEN_FRONTEND hvc_xen: implement multiconsole support hvc_xen: support PV on HVM consoles xenbus: don't free other end details too early xen/enlighten: Expose MWAIT and MWAIT_LEAF if hypervisor OKs it. xen/setup/pm/acpi: Remove the call to boot_option_idle_override. xenbus: address compiler warnings xen: use this_cpu_xxx replace percpu_xxx funcs xen/pciback: Support pci_reset_function, aka FLR or D3 support. pci: Introduce __pci_reset_function_locked to be used when holding device_lock. xen: Utilize the restore_msi_irqs hook.
2012-03-16powerpc/hvc_udbg: Don't crash when udbg_putc is NULLBenjamin Herrenschmidt
Also while at it, add some help text indicating why you shouldn't enable that driver under normal circumstances Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-03-13hvc_xen: introduce HVC_XEN_FRONTENDStefano Stabellini
Introduce a new config option HVC_XEN_FRONTEND to enable/disable the xenbus based pv console frontend. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-03-09tty: powerpc: remove hvc_iseriesStephen Rothwell
The PowerPC legacy iSeries platform is being removed, so this code is no longer needed. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-09-20powerpc/powernv: Support for OPAL consoleBenjamin Herrenschmidt
This adds a udbg and an hvc console backend for supporting a console using the OPAL console interfaces. On OPAL v1 we have hvc0 mapped to whatever console the system was configured for (network or hvsi serial port) via the service processor. On OPAL v2 we have hvcN mapped to the Nth console provided by OPAL which generally corresponds to: hvc0 : network console (raw protocol) hvc1 : serial port S1 (hvsi) hvc2 : serial port S2 (hvsi) Note: At this point, early debug console only works with OPAL v1 and shouldn't be enabled in a normal kernel. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-06-29powerpc/pseries: Re-implement HVSI as part of hvc_vioBenjamin Herrenschmidt
On pseries machines, consoles are provided by the hypervisor using a low level get_chars/put_chars type interface. However, this is really just a transport to the service processor which implements them either as "raw" console (networked consoles, HMC, ...) or as "hvsi" serial ports. The later is a simple packet protocol on top of the raw character interface that is supposed to convey additional "serial port" style semantics. In practice however, all it does is provide a way to read the CD line and set/clear our DTR line, that's it. We currently implement the "raw" protocol as an hvc console backend (/dev/hvcN) and the "hvsi" protocol using a separate tty driver (/dev/hvsi0). However this is quite impractical. The arbitrary difference between the two type of devices has been a major source of user (and distro) confusion. Additionally, there's an additional mini -hvsi implementation in the pseries platform code for our low level debug console and early boot kernel messages, which means code duplication, though that low level variant is impractical as it's incapable of doing the initial protocol negociation to establish the link to the FSP. This essentially replaces the dedicated hvsi driver and the platform udbg code completely by extending the existing hvc_vio backend used in "raw" mode so that: - It now supports HVSI as well - We add support for hvc backend providing tiocm{get,set} - It also provides a udbg interface for early debug and boot console This is overall less code, though this will only be obvious once we remove the old "hvsi" driver, which is still available for now. When the old driver is enabled, the new code still kicks in for the low level udbg console, replacing the old mini implementation in the platform code, it just doesn't provide the higher level "hvc" interface. In addition to producing generally simler code, this has several benefits over our current situation: - The user/distro only has to deal with /dev/hvcN for the hypervisor console, avoiding all sort of confusion that has plagued us in the past - The tty, kernel and low level debug console all use the same code base which supports the full protocol establishment process, thus the console is now available much earlier than it used to be with the old HVSI driver. The kernel console works much earlier and udbg is available much earlier too. Hackers can enable a hard coded very-early debug console as well that works with HVSI (previously that was only supported for the "raw" mode). I've tried to keep the same semantics as hvsi relative to how I react to things like CD changes, with some subtle differences though: - I clear DTR on close if HUPCL is set - Current hvsi triggers a hangup if it detects a up->down transition on CD (you can still open a console with CD down). My new implementation triggers a hangup if the link to the FSP is severed, and severs it upon detecting a up->down transition on CD. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-02-22tty: move Kconfig entries into drivers/tty from drivers/charGreg Kroah-Hartman
The Kconfig options for the drivers/tty/ files still were hanging around in the "big" drivers/char/Kconfig file, so move them to the proper location under drivers/tty and drivers/tty/hvc/ Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>