user/sven/linux.git/drivers/tty/Kconfig, branch v4.9.74

devpts: Make each mount of devpts an independent filesystem.

2016-06-05T17:36:01Z

The /dev/ptmx device node is changed to lookup the directory entry "pts" in the same directory as the /dev/ptmx device node was opened in. If there is a "pts" entry and that entry is a devpts filesystem /dev/ptmx uses that filesystem. Otherwise the open of /dev/ptmx fails. The DEVPTS_MULTIPLE_INSTANCES configuration option is removed, so that userspace can now safely depend on each mount of devpts creating a new instance of the filesystem. Each mount of devpts is now a separate and equal filesystem. Reserved ttys are now available to all instances of devpts where the mounter is in the initial mount namespace. A new vfs helper path_pts is introduced that finds a directory entry named "pts" in the directory of the passed in path, and changes the passed in path to point to it. The helper path_pts uses a function path_parent_directory that was factored out of follow_dotdot. In the implementation of devpts: - devpts_mnt is killed as it is no longer meaningful if all mounts of devpts are equal. - pts_sb_from_inode is replaced by just inode->i_sb as all cached inodes in the tty layer are now from the devpts filesystem. - devpts_add_ref is rolled into the new function devpts_ptmx. And the unnecessary inode hold is removed. - devpts_del_ref is renamed devpts_release and reduced to just a deacrivate_super. - The newinstance mount option continues to be accepted but is now ignored. In devpts_fs.h definitions for when !CONFIG_UNIX98_PTYS are removed as they are never used. Documentation/filesystems/devices.txt is updated to describe the current situation. This has been verified to work properly on openwrt-15.05, centos5, centos6, centos7, debian-6.0.2, debian-7.9, debian-8.2, ubuntu-14.04.3, ubuntu-15.10, fedora23, magia-5, mint-17.3, opensuse-42.1, slackware-14.1, gentoo-20151225 (13.0?), archlinux-2015-12-01. With the caveat that on centos6 and on slackware-14.1 that there wind up being two instances of the devpts filesystem mounted on /dev/pts, the lower copy does not end up getting used. Signed-off-by: "Eric W. Biederman" Cc: Greg KH Cc: Peter Hurley Cc: Peter Anvin Cc: Andy Lutomirski Cc: Al Viro Cc: Serge Hallyn Cc: Willy Tarreau Cc: Aurelien Jarno Cc: One Thousand Gnomes Cc: Jann Horn Cc: Jiri Slaby Cc: Florian Weimer Cc: Konstantin Khlebnikov Signed-off-by: Linus Torvalds

tty: cyclades: cyz_interrupt is only used for PCI

2016-02-07T07:41:17Z

When CONFIG_PCI is not set, enabling CONFIG_CYZ_INTR has no practical effect other than generating a warning about an unused function: drivers/tty/cyclades.c:1184:20: warning: 'cyz_interrupt' defined but not used [-Wunused-function] static irqreturn_t cyz_interrupt(int irq, void *dev_id) This adds a dependency to avoid that warning. Signed-off-by: Arnd Bergmann Signed-off-by: Greg Kroah-Hartman

ttyFDC: Implement KGDB IO operations.

2015-03-31T10:04:13Z

Implement KGDB IO operations for MIPS Fast Debug Channel (FDC). This can be enabled via Kconfig, which also allows the channel number to be chosen. The magic sysrq hack is implemented in the TTY driver, detecting just ^C for the KGDB channel, and ^O followed by a letter for the FDC console channel. The KGDB operations are reasonably efficient thanks to the flush callback, with a 4 byte buffer being used in both directions to allow up to 4 bytes to be encoded per FDC word. Reading of data for KGDB will discard any data received on other channels, which clearly isn't ideal, but given that there is a single FIFO shared between channels we can't do much better. Signed-off-by: James Hogan Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: Jason Wessel Cc: linux-mips@linux-mips.org Cc: kgdb-bugreport@lists.sourceforge.net Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/9147/ Signed-off-by: Ralf Baechle

MIPS, ttyFDC: Add early FDC console support

2015-03-31T10:04:12Z

Add support for early console of MIPS Fast Debug Channel (FDC) on channel 1 with a call very early from the MIPS setup_arch(). Signed-off-by: James Hogan Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/9145/ Signed-off-by: Ralf Baechle

TTY: Add MIPS EJTAG Fast Debug Channel TTY driver

2015-03-31T10:04:12Z

Add TTY driver and consoles for the MIPS EJTAG Fast Debug Channel (FDC), which is found on the per-CPU MIPS Common Device Mapped Memory (CDMM) bus. The FDC is a per-CPU device which is used to communicate with an EJTAG probe. RX and TX FIFOs exist, containing 32-bits of data and 4-bit channel numbers. 16 general data streams are implemented on this for TTY and console use by encoding up to 4 bytes on each 32-bit FDC word. The TTY devices are named e.g. /dev/ttyFDC3c2 for channel 2 of the FDC attached to logical CPU 3. These can be used for getting the kernel log, a login prompt, or as a GDB remote transport, all over EJTAG and without needing a serial port. It can have an interrupt to notify of when incoming data is available in the RX FIFO or when the TX FIFO is no longer full. The detection of this interrupt occurs in architecture / platform code, but it may be shared with the timer and/or performance counter interrupt. Due to the per-CPU nature of the hardware, all outgoing TTY data is written out from a kthread which is pinned to the appropriate CPU. The console is not bound to a specific CPU, so output will appear on the chosen channel on whichever CPU the code is executing on. Enable with e.g. console=fdc1 in kernel arguments. /dev/console is bound to the same channel on the boot CPU's FDC if it exists. Signed-off-by: James Hogan Cc: Ralf Baechle Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/9146/ Signed-off-by: Ralf Baechle

drivers/tty: ehv_bytechan fails to build as a module

2014-01-09T23:52:12Z

ehv_bytechan is marked tristate but fails to build as a module: drivers/tty/ehv_bytechan.c:363:1: error: type defaults to ‘int’ in declaration of ‘console_initcall’ [-Werror=implicit-int] It doesn't make much sense for a console driver to be built as a module, so change it to a bool. Signed-off-by: Anton Blanchard Acked-by: Greg Kroah-Hartman Signed-off-by: Scott Wood

tty: metag_da: Add metag DA TTY driver

2013-02-06T19:10:17Z

Add a TTY driver for communicating over a Meta DA (Debug Adapter) channel using the bios channel SWITCH operation. Signed-off-by: James Hogan Cc: Jiri Slaby Acked-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman

goldfish: tty driver

2013-01-21T23:30:08Z

This provides a console driver for the Goldfish virtual platform. The original is from Arve with changes from Jun Nakajima and Tom Keel. This has been then been ported to the current kernel and to the tty port mechanism by Alan Cox. In the process it gained proper POSIX semantics and vhangup works. The default name is not ttyS as this belongs to the 8250 driver. Instead ttyGFx is now used. In the normal usage case the first port serves as a kernel logging console and the second one carries various other data streams for the emulation. Signed-off-by: Arve Hjønnevåg [Cleaned up to handle x86] Signed-off-by: Sheng Yang Signed-off-by: Yunhong Jiang Signed-off-by: Xiaohui Xin Signed-off-by: Jun Nakajima Signed-off-by: Bruce Beare [Moved to 3.7 and chunks rewritten to use tty_port layer] Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman

tty: Added a CONFIG_TTY option to allow removal of TTY

2013-01-19T00:15:27Z

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 Reviewed-by: Jamey Sharp Reviewed-by: Josh Triplett Signed-off-by: Greg Kroah-Hartman

Merge branch 'for-upstream' of http://github.com/agraf/linux-2.6 into queue

2012-10-10T22:03:54Z

* 'for-upstream' of http://github.com/agraf/linux-2.6: (56 commits) arch/powerpc/kvm/e500_tlb.c: fix error return code KVM: PPC: Book3S HV: Provide a way for userspace to get/set per-vCPU areas KVM: PPC: Book3S: Get/set guest FP regs using the GET/SET_ONE_REG interface KVM: PPC: Book3S: Get/set guest SPRs using the GET/SET_ONE_REG interface KVM: PPC: set IN_GUEST_MODE before checking requests KVM: PPC: e500: MMU API: fix leak of shared_tlb_pages KVM: PPC: e500: fix allocation size error on g2h_tlb1_map KVM: PPC: Book3S HV: Fix calculation of guest phys address for MMIO emulation KVM: PPC: Book3S HV: Remove bogus update of physical thread IDs KVM: PPC: Book3S HV: Fix updates of vcpu->cpu KVM: Move some PPC ioctl definitions to the correct place KVM: PPC: Book3S HV: Handle memory slot deletion and modification correctly KVM: PPC: Move kvm->arch.slot_phys into memslot.arch KVM: PPC: Book3S HV: Take the SRCU read lock before looking up memslots KVM: PPC: bookehv: Allow duplicate calls of DO_KVM macro KVM: PPC: BookE: Support FPU on non-hv systems KVM: PPC: 440: Implement mfdcrx KVM: PPC: 440: Implement mtdcrx Document IACx/DACx registers access using ONE_REG API KVM: PPC: E500: Remove E500_TLB_DIRTY flag ...