intel-gtt: maximize ggtt size on platforms that support this

[linux/fpc-iii.git] / drivers / char / Kconfig

#
# Character device configuration
#

menu "Character devices"

config VT
        bool "Virtual terminal" if EMBEDDED
        depends on !S390
        select INPUT
        default y
        ---help---
          If you say Y here, you will get support for terminal devices with
          display and keyboard devices. These are called "virtual" because you
          can run several virtual terminals (also called virtual consoles) on
          one physical terminal. This is rather useful, for example one
          virtual terminal can collect system messages and warnings, another
          one can be used for a text-mode user session, and a third could run
          an X session, all in parallel. Switching between virtual terminals
          is done with certain key combinations, usually Alt-<function key>.

          The setterm command ("man setterm") can be used to change the
          properties (such as colors or beeping) of a virtual terminal. The
          man page console_codes(4) ("man console_codes") contains the special
          character sequences that can be used to change those properties
          directly. The fonts used on virtual terminals can be changed with
          the setfont ("man setfont") command and the key bindings are defined
          with the loadkeys ("man loadkeys") command.

          You need at least one virtual terminal device in order to make use
          of your keyboard and monitor. Therefore, only people configuring an
          embedded system would want to say N here in order to save some
          memory; the only way to log into such a system is then via a serial
          or network connection.

          If unsure, say Y, or else you won't be able to do much with your new
          shiny Linux system :-)

config CONSOLE_TRANSLATIONS
        depends on VT
        default y
        bool "Enable character translations in console" if EMBEDDED
        ---help---
          This enables support for font mapping and Unicode translation
          on virtual consoles.

config VT_CONSOLE
        bool "Support for console on virtual terminal" if EMBEDDED
        depends on VT
        default y
        ---help---
          The system console is the device which receives all kernel messages
          and warnings and which allows logins in single user mode. If you
          answer Y here, a virtual terminal (the device used to interact with
          a physical terminal) can be used as system console. This is the most
          common mode of operations, so you should say Y here unless you want
          the kernel messages be output only to a serial port (in which case
          you should say Y to "Console on serial port", below).

          If you do say Y here, by default the currently visible virtual
          terminal (/dev/tty0) will be used as system console. You can change
          that with a kernel command line option such as "console=tty3" which
          would use the third virtual terminal as system console. (Try "man
          bootparam" or see the documentation of your boot loader (lilo or
          loadlin) about how to pass options to the kernel at boot time.)

          If unsure, say Y.

config HW_CONSOLE
        bool
        depends on VT && !S390 && !UML
        default y

config VT_HW_CONSOLE_BINDING
       bool "Support for binding and unbinding console drivers"
       depends on HW_CONSOLE
       default n
       ---help---
         The virtual terminal is the device that interacts with the physical
         terminal through console drivers. On these systems, at least one
         console driver is loaded. In other configurations, additional console
         drivers may be enabled, such as the framebuffer console. If more than
         1 console driver is enabled, setting this to 'y' will allow you to
         select the console driver that will serve as the backend for the
         virtual terminals.

         See <file:Documentation/console/console.txt> for more
         information. For framebuffer console users, please refer to
         <file:Documentation/fb/fbcon.txt>.

config DEVKMEM
        bool "/dev/kmem virtual device support"
        default y
        help
          Say Y here if you want to support the /dev/kmem device. The
          /dev/kmem device is rarely used, but can be used for certain
          kind of kernel debugging operations.
          When in doubt, say "N".

config BFIN_JTAG_COMM
        tristate "Blackfin JTAG Communication"
        depends on BLACKFIN
        help
          Add support for emulating a TTY device over the Blackfin JTAG.

          To compile this driver as a module, choose M here: the
          module will be called bfin_jtag_comm.

config BFIN_JTAG_COMM_CONSOLE
        bool "Console on Blackfin JTAG"
        depends on BFIN_JTAG_COMM=y

config SERIAL_NONSTANDARD
        bool "Non-standard serial port support"
        depends on HAS_IOMEM
        ---help---
          Say Y here if you have any non-standard serial boards -- boards
          which aren't supported using the standard "dumb" serial driver.
          This includes intelligent serial boards such as Cyclades,
          Digiboards, etc. These are usually used for systems that need many
          serial ports because they serve many terminals or dial-in
          connections.

          Note that the answer to this question won't directly affect the
          kernel: saying N will just cause the configurator to skip all
          the questions about non-standard serial boards.

          Most people can say N here.

config COMPUTONE
        tristate "Computone IntelliPort Plus serial support"
        depends on SERIAL_NONSTANDARD && (ISA || EISA || PCI)
        ---help---
          This driver supports the entire family of Intelliport II/Plus
          controllers with the exception of the MicroChannel controllers and
          products previous to the Intelliport II. These are multiport cards,
          which give you many serial ports. You would need something like this
          to connect more than two modems to your Linux box, for instance in
          order to become a dial-in server. If you have a card like that, say
          Y here and read <file:Documentation/serial/computone.txt>.

          To compile this driver as module, choose M here: the
          module will be called ip2.

config ROCKETPORT
        tristate "Comtrol RocketPort support"
        depends on SERIAL_NONSTANDARD && (ISA || EISA || PCI)
        help
          This driver supports Comtrol RocketPort and RocketModem PCI boards.   
          These boards provide 2, 4, 8, 16, or 32 high-speed serial ports or
          modems.  For information about the RocketPort/RocketModem  boards
          and this driver read <file:Documentation/serial/rocket.txt>.

          To compile this driver as a module, choose M here: the
          module will be called rocket.

          If you want to compile this driver into the kernel, say Y here.  If
          you don't have a Comtrol RocketPort/RocketModem card installed, say N.

config CYCLADES
        tristate "Cyclades async mux support"
        depends on SERIAL_NONSTANDARD && (PCI || ISA)
        select FW_LOADER
        ---help---
          This driver supports Cyclades Z and Y multiserial boards.
          You would need something like this to connect more than two modems to
          your Linux box, for instance in order to become a dial-in server.

          For information about the Cyclades-Z card, read
          <file:Documentation/serial/README.cycladesZ>.

          To compile this driver as a module, choose M here: the
          module will be called cyclades.

          If you haven't heard about it, it's safe to say N.

config CYZ_INTR
        bool "Cyclades-Z interrupt mode operation (EXPERIMENTAL)"
        depends on EXPERIMENTAL && CYCLADES
        help
          The Cyclades-Z family of multiport cards allows 2 (two) driver op
          modes: polling and interrupt. In polling mode, the driver will check
          the status of the Cyclades-Z ports every certain amount of time
          (which is called polling cycle and is configurable). In interrupt
          mode, it will use an interrupt line (IRQ) in order to check the
          status of the Cyclades-Z ports. The default op mode is polling. If
          unsure, say N.

config DIGIEPCA
        tristate "Digiboard Intelligent Async Support"
        depends on SERIAL_NONSTANDARD && (ISA || EISA || PCI)
        ---help---
          This is a driver for Digi International's Xx, Xeve, and Xem series
          of cards which provide multiple serial ports. You would need
          something like this to connect more than two modems to your Linux
          box, for instance in order to become a dial-in server. This driver
          supports the original PC (ISA) boards as well as PCI, and EISA. If
          you have a card like this, say Y here and read the file
          <file:Documentation/serial/digiepca.txt>.

          To compile this driver as a module, choose M here: the
          module will be called epca.

config MOXA_INTELLIO
        tristate "Moxa Intellio support"
        depends on SERIAL_NONSTANDARD && (ISA || EISA || PCI)
        select FW_LOADER
        help
          Say Y here if you have a Moxa Intellio multiport serial card.

          To compile this driver as a module, choose M here: the
          module will be called moxa.

config MOXA_SMARTIO
        tristate "Moxa SmartIO support v. 2.0"
        depends on SERIAL_NONSTANDARD && (PCI || EISA || ISA)
        help
          Say Y here if you have a Moxa SmartIO multiport serial card and/or
          want to help develop a new version of this driver.

          This is upgraded (1.9.1) driver from original Moxa drivers with
          changes finally resulting in PCI probing.

          This driver can also be built as a module. The module will be called
          mxser. If you want to do that, say M here.

config ISI
        tristate "Multi-Tech multiport card support (EXPERIMENTAL)"
        depends on SERIAL_NONSTANDARD && PCI
        select FW_LOADER
        help
          This is a driver for the Multi-Tech cards which provide several
          serial ports.  The driver is experimental and can currently only be
          built as a module. The module will be called isicom.
          If you want to do that, choose M here.

config SYNCLINK
        tristate "Microgate SyncLink card support"
        depends on SERIAL_NONSTANDARD && PCI && ISA_DMA_API
        help
          Provides support for the SyncLink ISA and PCI multiprotocol serial
          adapters. These adapters support asynchronous and HDLC bit
          synchronous communication up to 10Mbps (PCI adapter).

          This driver can only be built as a module ( = code which can be
          inserted in and removed from the running kernel whenever you want).
          The module will be called synclink.  If you want to do that, say M
          here.

config SYNCLINKMP
        tristate "SyncLink Multiport support"
        depends on SERIAL_NONSTANDARD && PCI
        help
          Enable support for the SyncLink Multiport (2 or 4 ports)
          serial adapter, running asynchronous and HDLC communications up
          to 2.048Mbps. Each ports is independently selectable for
          RS-232, V.35, RS-449, RS-530, and X.21

          This driver may be built as a module ( = code which can be
          inserted in and removed from the running kernel whenever you want).
          The module will be called synclinkmp.  If you want to do that, say M
          here.

config SYNCLINK_GT
        tristate "SyncLink GT/AC support"
        depends on SERIAL_NONSTANDARD && PCI
        help
          Support for SyncLink GT and SyncLink AC families of
          synchronous and asynchronous serial adapters
          manufactured by Microgate Systems, Ltd. (www.microgate.com)

config N_HDLC
        tristate "HDLC line discipline support"
        depends on SERIAL_NONSTANDARD
        help
          Allows synchronous HDLC communications with tty device drivers that
          support synchronous HDLC such as the Microgate SyncLink adapter.

          This driver can be built as a module ( = code which can be
          inserted in and removed from the running kernel whenever you want).
          The module will be called n_hdlc. If you want to do that, say M
          here.

config N_GSM
        tristate "GSM MUX line discipline support (EXPERIMENTAL)"
        depends on EXPERIMENTAL
        depends on NET
        help
          This line discipline provides support for the GSM MUX protocol and
          presents the mux as a set of 61 individual tty devices.

config RISCOM8
        tristate "SDL RISCom/8 card support"
        depends on SERIAL_NONSTANDARD
        help
          This is a driver for the SDL Communications RISCom/8 multiport card,
          which gives you many serial ports. You would need something like
          this to connect more than two modems to your Linux box, for instance
          in order to become a dial-in server. If you have a card like that,
          say Y here and read the file <file:Documentation/serial/riscom8.txt>.

          Also it's possible to say M here and compile this driver as kernel
          loadable module; the module will be called riscom8.

config SPECIALIX
        tristate "Specialix IO8+ card support"
        depends on SERIAL_NONSTANDARD
        help
          This is a driver for the Specialix IO8+ multiport card (both the
          ISA and the PCI version) which gives you many serial ports. You
          would need something like this to connect more than two modems to
          your Linux box, for instance in order to become a dial-in server.

          If you have a card like that, say Y here and read the file
          <file:Documentation/serial/specialix.txt>. Also it's possible to say
          M here and compile this driver as kernel loadable module which will be
          called specialix.

config SX
        tristate "Specialix SX (and SI) card support"
        depends on SERIAL_NONSTANDARD && (PCI || EISA || ISA) && BROKEN
        help
          This is a driver for the SX and SI multiport serial cards.
          Please read the file <file:Documentation/serial/sx.txt> for details.

          This driver can only be built as a module ( = code which can be
          inserted in and removed from the running kernel whenever you want).
          The module will be called sx. If you want to do that, say M here.

config RIO
        tristate "Specialix RIO system support"
        depends on SERIAL_NONSTANDARD && BROKEN
        help
          This is a driver for the Specialix RIO, a smart serial card which
          drives an outboard box that can support up to 128 ports.  Product
          information is at <http://www.perle.com/support/documentation.html#multiport>.
          There are both ISA and PCI versions.

config RIO_OLDPCI
        bool "Support really old RIO/PCI cards"
        depends on RIO
        help
          Older RIO PCI cards need some initialization-time configuration to
          determine the IRQ and some control addresses.  If you have a RIO and
          this doesn't seem to work, try setting this to Y.

config STALDRV
        bool "Stallion multiport serial support"
        depends on SERIAL_NONSTANDARD
        help
          Stallion cards give you many serial ports.  You would need something
          like this to connect more than two modems to your Linux box, for
          instance in order to become a dial-in server.  If you say Y here,
          you will be asked for your specific card model in the next
          questions.  Make sure to read <file:Documentation/serial/stallion.txt>
          in this case.  If you have never heard about all this, it's safe to
          say N.

config STALLION
        tristate "Stallion EasyIO or EC8/32 support"
        depends on STALDRV && (ISA || EISA || PCI)
        help
          If you have an EasyIO or EasyConnection 8/32 multiport Stallion
          card, then this is for you; say Y.  Make sure to read
          <file:Documentation/serial/stallion.txt>.

          To compile this driver as a module, choose M here: the
          module will be called stallion.

config ISTALLION
        tristate "Stallion EC8/64, ONboard, Brumby support"
        depends on STALDRV && (ISA || EISA || PCI)
        help
          If you have an EasyConnection 8/64, ONboard, Brumby or Stallion
          serial multiport card, say Y here. Make sure to read
          <file:Documentation/serial/stallion.txt>.

          To compile this driver as a module, choose M here: the
          module will be called istallion.

config NOZOMI
        tristate "HSDPA Broadband Wireless Data Card - Globe Trotter"
        depends on PCI && EXPERIMENTAL
        help
          If you have a HSDPA driver Broadband Wireless Data Card -
          Globe Trotter PCMCIA card, say Y here.

          To compile this driver as a module, choose M here, the module
          will be called nozomi.

config A2232
        tristate "Commodore A2232 serial support (EXPERIMENTAL)"
        depends on EXPERIMENTAL && ZORRO && BROKEN
        ---help---
          This option supports the 2232 7-port serial card shipped with the
          Amiga 2000 and other Zorro-bus machines, dating from 1989.  At
          a max of 19,200 bps, the ports are served by a 6551 ACIA UART chip
          each, plus a 8520 CIA, and a master 6502 CPU and buffer as well. The
          ports were connected with 8 pin DIN connectors on the card bracket,
          for which 8 pin to DB25 adapters were supplied. The card also had
          jumpers internally to toggle various pinning configurations.

          This driver can be built as a module; but then "generic_serial"
          will also be built as a module. This has to be loaded before
          "ser_a2232". If you want to do this, answer M here.

config SGI_SNSC
        bool "SGI Altix system controller communication support"
        depends on (IA64_SGI_SN2 || IA64_GENERIC)
        help
          If you have an SGI Altix and you want to enable system
          controller communication from user space (you want this!),
          say Y.  Otherwise, say N.

config SGI_TIOCX
       bool "SGI TIO CX driver support"
       depends on (IA64_SGI_SN2 || IA64_GENERIC)
       help
         If you have an SGI Altix and you have fpga devices attached
         to your TIO, say Y here, otherwise say N.

config SGI_MBCS
       tristate "SGI FPGA Core Services driver support"
       depends on SGI_TIOCX
       help
         If you have an SGI Altix with an attached SABrick
         say Y or M here, otherwise say N.

source "drivers/serial/Kconfig"

config UNIX98_PTYS
        bool "Unix98 PTY support" if EMBEDDED
        default y
        ---help---
          A pseudo terminal (PTY) is a software device consisting of two
          halves: a master and a slave. The slave device behaves identical to
          a physical terminal; the master device is used by a process to
          read data from and write data to the slave, thereby emulating a
          terminal. Typical programs for the master side are telnet servers
          and xterms.

          Linux has traditionally used the BSD-like names /dev/ptyxx for
          masters and /dev/ttyxx for slaves of pseudo terminals. This scheme
          has a number of problems. The GNU C library glibc 2.1 and later,
          however, supports the Unix98 naming standard: in order to acquire a
          pseudo terminal, a process opens /dev/ptmx; the number of the pseudo
          terminal is then made available to the process and the pseudo
          terminal slave can be accessed as /dev/pts/<number>. What was
          traditionally /dev/ttyp2 will then be /dev/pts/2, for example.

          All modern Linux systems use the Unix98 ptys.  Say Y unless
          you're on an embedded system and want to conserve memory.

config DEVPTS_MULTIPLE_INSTANCES
        bool "Support multiple instances of devpts"
        depends on UNIX98_PTYS
        default n
        ---help---
          Enable support for multiple instances of devpts filesystem.
          If you want to have isolated PTY namespaces (eg: in containers),
          say Y here.  Otherwise, say N. If enabled, each mount of devpts
          filesystem with the '-o newinstance' option will create an
          independent PTY namespace.

config LEGACY_PTYS
        bool "Legacy (BSD) PTY support"
        default y
        ---help---
          A pseudo terminal (PTY) is a software device consisting of two
          halves: a master and a slave. The slave device behaves identical to
          a physical terminal; the master device is used by a process to
          read data from and write data to the slave, thereby emulating a
          terminal. Typical programs for the master side are telnet servers
          and xterms.

          Linux has traditionally used the BSD-like names /dev/ptyxx
          for masters and /dev/ttyxx for slaves of pseudo
          terminals. This scheme has a number of problems, including
          security.  This option enables these legacy devices; on most
          systems, it is safe to say N.


config LEGACY_PTY_COUNT
        int "Maximum number of legacy PTY in use"
        depends on LEGACY_PTYS
        range 0 256
        default "256"
        ---help---
          The maximum number of legacy PTYs that can be used at any one time.
          The default is 256, and should be more than enough.  Embedded
          systems may want to reduce this to save memory.

          When not in use, each legacy PTY occupies 12 bytes on 32-bit
          architectures and 24 bytes on 64-bit architectures.

config TTY_PRINTK
        bool "TTY driver to output user messages via printk"
        depends on EMBEDDED
        default n
        ---help---
          If you say Y here, the support for writing user messages (i.e.
          console messages) via printk is available.

          The feature is useful to inline user messages with kernel
          messages.
          In order to use this feature, you should output user messages
          to /dev/ttyprintk or redirect console to this TTY.

          If unsure, say N.

config BRIQ_PANEL
        tristate 'Total Impact briQ front panel driver'
        depends on PPC_CHRP
        ---help---
          The briQ is a small footprint CHRP computer with a frontpanel VFD, a
          tristate led and two switches. It is the size of a CDROM drive.

          If you have such one and want anything showing on the VFD then you
          must answer Y here.

          To compile this driver as a module, choose M here: the
          module will be called briq_panel.

          It's safe to say N here.

config BFIN_OTP
        tristate "Blackfin On-Chip OTP Memory Support"
        depends on BLACKFIN && (BF51x || BF52x || BF54x)
        default y
        help
          If you say Y here, you will get support for a character device
          interface into the One Time Programmable memory pages that are
          stored on the Blackfin processor.  This will not get you access
          to the secure memory pages however.  You will need to write your
          own secure code and reader for that.

          To compile this driver as a module, choose M here: the module
          will be called bfin-otp.

          If unsure, it is safe to say Y.

config BFIN_OTP_WRITE_ENABLE
        bool "Enable writing support of OTP pages"
        depends on BFIN_OTP
        default n
        help
          If you say Y here, you will enable support for writing of the
          OTP pages.  This is dangerous by nature as you can only program
          the pages once, so only enable this option when you actually
          need it so as to not inadvertently clobber data.

          If unsure, say N.

config PRINTER
        tristate "Parallel printer support"
        depends on PARPORT
        ---help---
          If you intend to attach a printer to the parallel port of your Linux
          box (as opposed to using a serial printer; if the connector at the
          printer has 9 or 25 holes ["female"], then it's serial), say Y.
          Also read the Printing-HOWTO, available from
          <http://www.tldp.org/docs.html#howto>.

          It is possible to share one parallel port among several devices
          (e.g. printer and ZIP drive) and it is safe to compile the
          corresponding drivers into the kernel.

          To compile this driver as a module, choose M here and read
          <file:Documentation/parport.txt>.  The module will be called lp.

          If you have several parallel ports, you can specify which ports to
          use with the "lp" kernel command line option.  (Try "man bootparam"
          or see the documentation of your boot loader (lilo or loadlin) about
          how to pass options to the kernel at boot time.)  The syntax of the
          "lp" command line option can be found in <file:drivers/char/lp.c>.

          If you have more than 8 printers, you need to increase the LP_NO
          macro in lp.c and the PARPORT_MAX macro in parport.h.

config LP_CONSOLE
        bool "Support for console on line printer"
        depends on PRINTER
        ---help---
          If you want kernel messages to be printed out as they occur, you
          can have a console on the printer. This option adds support for
          doing that; to actually get it to happen you need to pass the
          option "console=lp0" to the kernel at boot time.

          If the printer is out of paper (or off, or unplugged, or too
          busy..) the kernel will stall until the printer is ready again.
          By defining CONSOLE_LP_STRICT to 0 (at your own risk) you
          can make the kernel continue when this happens,
          but it'll lose the kernel messages.

          If unsure, say N.

config PPDEV
        tristate "Support for user-space parallel port device drivers"
        depends on PARPORT
        ---help---
          Saying Y to this adds support for /dev/parport device nodes.  This
          is needed for programs that want portable access to the parallel
          port, for instance deviceid (which displays Plug-and-Play device
          IDs).

          This is the parallel port equivalent of SCSI generic support (sg).
          It is safe to say N to this -- it is not needed for normal printing
          or parallel port CD-ROM/disk support.

          To compile this driver as a module, choose M here: the
          module will be called ppdev.

          If unsure, say N.

config HVC_DRIVER
        bool
        help
          Generic "hypervisor virtual console" infrastructure for various
          hypervisors (pSeries, iSeries, Xen, lguest).
          It will automatically be selected if one of the back-end console drivers
          is selected.

config HVC_IRQ
        bool

config HVC_CONSOLE
        bool "pSeries Hypervisor Virtual Console support"
        depends on PPC_PSERIES
        select HVC_DRIVER
        select HVC_IRQ
        help
          pSeries machines when partitioned support a hypervisor virtual
          console. This driver allows each pSeries partition to have a console
          which is accessed via the HMC.

config HVC_ISERIES
        bool "iSeries Hypervisor Virtual Console support"
        depends on PPC_ISERIES
        default y
        select HVC_DRIVER
        select HVC_IRQ
        select VIOPATH
        help
          iSeries machines support a hypervisor virtual console.

config HVC_RTAS
        bool "IBM RTAS Console support"
        depends on PPC_RTAS
        select HVC_DRIVER
        help
          IBM Console device driver which makes use of RTAS

config HVC_BEAT
        bool "Toshiba's Beat Hypervisor Console support"
        depends on PPC_CELLEB
        select HVC_DRIVER
        help
          Toshiba's Cell Reference Set Beat Console device driver

config HVC_IUCV
        bool "z/VM IUCV Hypervisor console support (VM only)"
        depends on S390
        select HVC_DRIVER
        select IUCV
        default y
        help
          This driver provides a Hypervisor console (HVC) back-end to access
          a Linux (console) terminal via a z/VM IUCV communication path.

config HVC_XEN
        bool "Xen Hypervisor Console support"
        depends on XEN
        select HVC_DRIVER
        select HVC_IRQ
        default y
        help
          Xen virtual console device driver

config HVC_UDBG
       bool "udbg based fake hypervisor console"
       depends on PPC && EXPERIMENTAL
       select HVC_DRIVER
       default n

config VIRTIO_CONSOLE
        tristate "Virtio console"
        depends on VIRTIO
        select HVC_DRIVER
        help
          Virtio console for use with lguest and other hypervisors.

          Also serves as a general-purpose serial device for data
          transfer between the guest and host.  Character devices at
          /dev/vportNpn will be created when corresponding ports are
          found, where N is the device number and n is the port number
          within that device.  If specified by the host, a sysfs
          attribute called 'name' will be populated with a name for
          the port which can be used by udev scripts to create a
          symlink to the device.

config HVCS
        tristate "IBM Hypervisor Virtual Console Server support"
        depends on PPC_PSERIES && HVC_CONSOLE
        help
          Partitionable IBM Power5 ppc64 machines allow hosting of
          firmware virtual consoles from one Linux partition by
          another Linux partition.  This driver allows console data
          from Linux partitions to be accessed through TTY device
          interfaces in the device tree of a Linux partition running
          this driver.

          To compile this driver as a module, choose M here: the
          module will be called hvcs.  Additionally, this module
          will depend on arch specific APIs exported from hvcserver.ko
          which will also be compiled when this driver is built as a
          module.

config IBM_BSR
        tristate "IBM POWER Barrier Synchronization Register support"
        depends on PPC_PSERIES
        help
          This devices exposes a hardware mechanism for fast synchronization
          of threads across a large system which avoids bouncing a cacheline
          between several cores on a system

source "drivers/char/ipmi/Kconfig"

config DS1620
        tristate "NetWinder thermometer support"
        depends on ARCH_NETWINDER
        help
          Say Y here to include support for the thermal management hardware
          found in the NetWinder. This driver allows the user to control the
          temperature set points and to read the current temperature.

          It is also possible to say M here to build it as a module (ds1620)
          It is recommended to be used on a NetWinder, but it is not a
          necessity.

config NWBUTTON
        tristate "NetWinder Button"
        depends on ARCH_NETWINDER
        ---help---
          If you say Y here and create a character device node /dev/nwbutton
          with major and minor numbers 10 and 158 ("man mknod"), then every
          time the orange button is pressed a number of times, the number of
          times the button was pressed will be written to that device.

          This is most useful for applications, as yet unwritten, which
          perform actions based on how many times the button is pressed in a
          row.

          Do not hold the button down for too long, as the driver does not
          alter the behaviour of the hardware reset circuitry attached to the
          button; it will still execute a hard reset if the button is held
          down for longer than approximately five seconds.

          To compile this driver as a module, choose M here: the
          module will be called nwbutton.

          Most people will answer Y to this question and "Reboot Using Button"
          below to be able to initiate a system shutdown from the button.

config NWBUTTON_REBOOT
        bool "Reboot Using Button"
        depends on NWBUTTON
        help
          If you say Y here, then you will be able to initiate a system
          shutdown and reboot by pressing the orange button a number of times.
          The number of presses to initiate the shutdown is two by default,
          but this can be altered by modifying the value of NUM_PRESSES_REBOOT
          in nwbutton.h and recompiling the driver or, if you compile the
          driver as a module, you can specify the number of presses at load
          time with "insmod button reboot_count=<something>".

config NWFLASH
        tristate "NetWinder flash support"
        depends on ARCH_NETWINDER
        ---help---
          If you say Y here and create a character device /dev/flash with
          major 10 and minor 160 you can manipulate the flash ROM containing
          the NetWinder firmware. Be careful as accidentally overwriting the
          flash contents can render your computer unbootable. On no account
          allow random users access to this device. :-)

          To compile this driver as a module, choose M here: the
          module will be called nwflash.

          If you're not sure, say N.

source "drivers/char/hw_random/Kconfig"

config NVRAM
        tristate "/dev/nvram support"
        depends on ATARI || X86 || (ARM && RTC_DRV_CMOS) || GENERIC_NVRAM
        ---help---
          If you say Y here and create a character special file /dev/nvram
          with major number 10 and minor number 144 using mknod ("man mknod"),
          you get read and write access to the extra bytes of non-volatile
          memory in the real time clock (RTC), which is contained in every PC
          and most Ataris.  The actual number of bytes varies, depending on the
          nvram in the system, but is usually 114 (128-14 for the RTC).

          This memory is conventionally called "CMOS RAM" on PCs and "NVRAM"
          on Ataris. /dev/nvram may be used to view settings there, or to
          change them (with some utility). It could also be used to frequently
          save a few bits of very important data that may not be lost over
          power-off and for which writing to disk is too insecure. Note
          however that most NVRAM space in a PC belongs to the BIOS and you
          should NEVER idly tamper with it. See Ralf Brown's interrupt list
          for a guide to the use of CMOS bytes by your BIOS.

          On Atari machines, /dev/nvram is always configured and does not need
          to be selected.

          To compile this driver as a module, choose M here: the
          module will be called nvram.

#
# These legacy RTC drivers just cause too many conflicts with the generic
# RTC framework ... let's not even try to coexist any more.
#
if RTC_LIB=n

config RTC
        tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
        depends on !PPC && !PARISC && !IA64 && !M68K && !SPARC && !FRV \
                        && !ARM && !SUPERH && !S390 && !AVR32 && !BLACKFIN
        ---help---
          If you say Y here and create a character special file /dev/rtc with
          major number 10 and minor number 135 using mknod ("man mknod"), you
          will get access to the real time clock (or hardware clock) built
          into your computer.

          Every PC has such a clock built in. It can be used to generate
          signals from as low as 1Hz up to 8192Hz, and can also be used
          as a 24 hour alarm. It reports status information via the file
          /proc/driver/rtc and its behaviour is set by various ioctls on
          /dev/rtc.

          If you run Linux on a multiprocessor machine and said Y to
          "Symmetric Multi Processing" above, you should say Y here to read
          and set the RTC in an SMP compatible fashion.

          If you think you have a use for such a device (such as periodic data
          sampling), then say Y here, and read <file:Documentation/rtc.txt>
          for details.

          To compile this driver as a module, choose M here: the
          module will be called rtc.

config JS_RTC
        tristate "Enhanced Real Time Clock Support"
        depends on SPARC32 && PCI
        ---help---
          If you say Y here and create a character special file /dev/rtc with
          major number 10 and minor number 135 using mknod ("man mknod"), you
          will get access to the real time clock (or hardware clock) built
          into your computer.

          Every PC has such a clock built in. It can be used to generate
          signals from as low as 1Hz up to 8192Hz, and can also be used
          as a 24 hour alarm. It reports status information via the file
          /proc/driver/rtc and its behaviour is set by various ioctls on
          /dev/rtc.

          If you think you have a use for such a device (such as periodic data
          sampling), then say Y here, and read <file:Documentation/rtc.txt>
          for details.

          To compile this driver as a module, choose M here: the
          module will be called js-rtc.

config GEN_RTC
        tristate "Generic /dev/rtc emulation"
        depends on RTC!=y && !IA64 && !ARM && !M32R && !MIPS && !SPARC && !FRV && !S390 && !SUPERH && !AVR32 && !BLACKFIN
        ---help---
          If you say Y here and create a character special file /dev/rtc with
          major number 10 and minor number 135 using mknod ("man mknod"), you
          will get access to the real time clock (or hardware clock) built
          into your computer.

          It reports status information via the file /proc/driver/rtc and its
          behaviour is set by various ioctls on /dev/rtc. If you enable the
          "extended RTC operation" below it will also provide an emulation
          for RTC_UIE which is required by some programs and may improve
          precision in some cases.

          To compile this driver as a module, choose M here: the
          module will be called genrtc.

config GEN_RTC_X
        bool "Extended RTC operation"
        depends on GEN_RTC
        help
          Provides an emulation for RTC_UIE which is required by some programs
          and may improve precision of the generic RTC support in some cases.

config EFI_RTC
        bool "EFI Real Time Clock Services"
        depends on IA64

config DS1302
        tristate "DS1302 RTC support"
        depends on M32R && (PLAT_M32700UT || PLAT_OPSPUT)
        help
          If you say Y here and create a character special file /dev/rtc with
          major number 121 and minor number 0 using mknod ("man mknod"), you
          will get access to the real time clock (or hardware clock) built
          into your computer.

endif # RTC_LIB

config DTLK
        tristate "Double Talk PC internal speech card support"
        depends on ISA
        help
          This driver is for the DoubleTalk PC, a speech synthesizer
          manufactured by RC Systems (<http://www.rcsys.com/>).  It is also
          called the `internal DoubleTalk'.

          To compile this driver as a module, choose M here: the
          module will be called dtlk.

config XILINX_HWICAP
        tristate "Xilinx HWICAP Support"
        depends on XILINX_VIRTEX || MICROBLAZE
        help
          This option enables support for Xilinx Internal Configuration
          Access Port (ICAP) driver.  The ICAP is used on Xilinx Virtex
          FPGA platforms to partially reconfigure the FPGA at runtime.

          If unsure, say N.

config R3964
        tristate "Siemens R3964 line discipline"
        ---help---
          This driver allows synchronous communication with devices using the
          Siemens R3964 packet protocol. Unless you are dealing with special
          hardware like PLCs, you are unlikely to need this.

          To compile this driver as a module, choose M here: the
          module will be called n_r3964.

          If unsure, say N.

config APPLICOM
        tristate "Applicom intelligent fieldbus card support"
        depends on PCI
        ---help---
          This driver provides the kernel-side support for the intelligent
          fieldbus cards made by Applicom International. More information
          about these cards can be found on the WWW at the address
          <http://www.applicom-int.com/>, or by email from David Woodhouse
          <dwmw2@infradead.org>.

          To compile this driver as a module, choose M here: the
          module will be called applicom.

          If unsure, say N.

config SONYPI
        tristate "Sony Vaio Programmable I/O Control Device support (EXPERIMENTAL)"
        depends on EXPERIMENTAL && X86 && PCI && INPUT && !64BIT
        ---help---
          This driver enables access to the Sony Programmable I/O Control
          Device which can be found in many (all ?) Sony Vaio laptops.

          If you have one of those laptops, read
          <file:Documentation/laptops/sonypi.txt>, and say Y or M here.

          To compile this driver as a module, choose M here: the
          module will be called sonypi.

config GPIO_TB0219
        tristate "TANBAC TB0219 GPIO support"
        depends on TANBAC_TB022X
        select GPIO_VR41XX

source "drivers/char/pcmcia/Kconfig"

config MWAVE
        tristate "ACP Modem (Mwave) support"
        depends on X86
        select SERIAL_8250
        ---help---
          The ACP modem (Mwave) for Linux is a WinModem. It is composed of a
          kernel driver and a user level application. Together these components
          support direct attachment to public switched telephone networks (PSTNs)
          and support selected world wide countries.

          This version of the ACP Modem driver supports the IBM Thinkpad 600E,
          600, and 770 that include on board ACP modem hardware.

          The modem also supports the standard communications port interface
          (ttySx) and is compatible with the Hayes AT Command Set.

          The user level application needed to use this driver can be found at
          the IBM Linux Technology Center (LTC) web site:
          <http://www.ibm.com/linux/ltc/>.

          If you own one of the above IBM Thinkpads which has the Mwave chipset
          in it, say Y.

          To compile this driver as a module, choose M here: the
          module will be called mwave.

config SCx200_GPIO
        tristate "NatSemi SCx200 GPIO Support"
        depends on SCx200
        select NSC_GPIO
        help
          Give userspace access to the GPIO pins on the National
          Semiconductor SCx200 processors.

          If compiled as a module, it will be called scx200_gpio.

config PC8736x_GPIO
        tristate "NatSemi PC8736x GPIO Support"
        depends on X86_32
        default SCx200_GPIO     # mostly N
        select NSC_GPIO         # needed for support routines
        help
          Give userspace access to the GPIO pins on the National
          Semiconductor PC-8736x (x=[03456]) SuperIO chip.  The chip
          has multiple functional units, inc several managed by
          hwmon/pc87360 driver.  Tested with PC-87366

          If compiled as a module, it will be called pc8736x_gpio.

config NSC_GPIO
        tristate "NatSemi Base GPIO Support"
        depends on X86_32
        # selected by SCx200_GPIO and PC8736x_GPIO
        # what about 2 selectors differing: m != y
        help
          Common support used (and needed) by scx200_gpio and
          pc8736x_gpio drivers.  If those drivers are built as
          modules, this one will be too, named nsc_gpio

config CS5535_GPIO
        tristate "AMD CS5535/CS5536 GPIO (Geode Companion Device)"
        depends on X86_32
        help
          Give userspace access to the GPIO pins on the AMD CS5535 and
          CS5536 Geode companion devices.

          If compiled as a module, it will be called cs5535_gpio.

config RAW_DRIVER
        tristate "RAW driver (/dev/raw/rawN)"
        depends on BLOCK
        help
          The raw driver permits block devices to be bound to /dev/raw/rawN.
          Once bound, I/O against /dev/raw/rawN uses efficient zero-copy I/O.
          See the raw(8) manpage for more details.

          Applications should preferably open the device (eg /dev/hda1)
          with the O_DIRECT flag.

config MAX_RAW_DEVS
        int "Maximum number of RAW devices to support (1-8192)"
        depends on RAW_DRIVER
        default "256"
        help
          The maximum number of RAW devices that are supported.
          Default is 256. Increase this number in case you need lots of
          raw devices.

config HPET
        bool "HPET - High Precision Event Timer" if (X86 || IA64)
        default n
        depends on ACPI
        help
          If you say Y here, you will have a miscdevice named "/dev/hpet/".  Each
          open selects one of the timers supported by the HPET.  The timers are
          non-periodic and/or periodic.

config HPET_MMAP
        bool "Allow mmap of HPET"
        default y
        depends on HPET
        help
          If you say Y here, user applications will be able to mmap
          the HPET registers.

          In some hardware implementations, the page containing HPET
          registers may also contain other things that shouldn't be
          exposed to the user.  If this applies to your hardware,
          say N here.

config HANGCHECK_TIMER
        tristate "Hangcheck timer"
        depends on X86 || IA64 || PPC64 || S390
        help
          The hangcheck-timer module detects when the system has gone
          out to lunch past a certain margin.  It can reboot the system
          or merely print a warning.

config MMTIMER
        tristate "MMTIMER Memory mapped RTC for SGI Altix"
        depends on IA64_GENERIC || IA64_SGI_SN2
        default y
        help
          The mmtimer device allows direct userspace access to the
          Altix system timer.

config UV_MMTIMER
        tristate "UV_MMTIMER Memory mapped RTC for SGI UV"
        depends on X86_UV
        default m
        help
          The uv_mmtimer device allows direct userspace access to the
          UV system timer.

source "drivers/char/tpm/Kconfig"

config TELCLOCK
        tristate "Telecom clock driver for ATCA SBC"
        depends on EXPERIMENTAL && X86
        default n
        help
          The telecom clock device is specific to the MPCBL0010 and MPCBL0050
          ATCA computers and allows direct userspace access to the
          configuration of the telecom clock configuration settings.  This
          device is used for hardware synchronization across the ATCA backplane
          fabric.  Upon loading, the driver exports a sysfs directory,
          /sys/devices/platform/telco_clock, with a number of files for
          controlling the behavior of this hardware.

config DEVPORT
        bool
        depends on !M68K
        depends on ISA || PCI
        default y

source "drivers/s390/char/Kconfig"

config RAMOOPS
        tristate "Log panic/oops to a RAM buffer"
        depends on HAS_IOMEM
        default n
        help
          This enables panic and oops messages to be logged to a circular
          buffer in RAM where it can be read back at some later point.

endmenu