OpenCloudOS-Kernel/drivers/char/Kconfig

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#
# Character device configuration
#
menu "Character devices"
source "drivers/tty/Kconfig"
config DEVMEM
bool "/dev/mem virtual device support"
default y
help
Say Y here if you want to support the /dev/mem device.
The /dev/mem device is used to access areas of physical
memory.
When in doubt, say "Y".
config DEVKMEM
bool "/dev/kmem virtual device support"
drivers/char: kmem: disable on arm64 As it turns out, arm64 deviates from other architectures in the way it maps the VMALLOC region: on most (all?) other architectures, it resides strictly above the kernel's direct mapping of DRAM, but on arm64, this is the other way around. For instance, for a 48-bit VA configuration, we have modules : 0xffff000000000000 - 0xffff000008000000 ( 128 MB) vmalloc : 0xffff000008000000 - 0xffff7dffbfff0000 (129022 GB) ... vmemmap : 0xffff7e0000000000 - 0xffff800000000000 ( 2048 GB maximum) 0xffff7e0000000000 - 0xffff7e0003ff0000 ( 63 MB actual) memory : 0xffff800000000000 - 0xffff8000ffc00000 ( 4092 MB) This has mostly gone unnoticed until now, but it does appear that it breaks an assumption in the kmem read/write code, which does something like if (p < (unsigned long) high_memory) { ... use straight copy_[to|from]_user() using p as virtual address ... } ... if (count > 0) { ... use vread/vwrite for accesses past high_memory ... } The first condition will inadvertently hold for the VMALLOC region if VMALLOC_START < PAGE_OFFSET [which is the case on arm64], but the read or write will subsequently fail the virt_addr_valid() check, resulting in a -ENXIO return value. Given how kmem seems to be living in borrowed time anyway, and given the fact that nobody noticed that the read/write interface is broken on arm64 in the first place, let's not bother trying to fix it, but simply disable the /dev/kmem interface entirely for arm64. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-06-20 14:59:00 +08:00
# On arm64, VMALLOC_START < PAGE_OFFSET, which confuses kmem read/write
depends on !ARM64
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 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/tty/serial/Kconfig"
source "drivers/tty/serdev/Kconfig"
config TTY_PRINTK
tristate "TTY driver to output user messages via printk"
depends on EXPERT && TTY
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 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.
source "drivers/tty/hvc/Kconfig"
config VIRTIO_CONSOLE
tristate "Virtio console"
depends on VIRTIO && TTY
select HVC_DRIVER
help
Virtio console for use with 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 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
config POWERNV_OP_PANEL
tristate "IBM POWERNV Operator Panel Display support"
depends on PPC_POWERNV
default m
help
If you say Y here, a special character device node, /dev/op_panel,
will be created which exposes the operator panel display on IBM
Power Systems machines with FSPs.
If you don't require access to the operator panel display from user
space, say N.
If unsure, say M here to build it as a module called powernv-op-panel.
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 ALPHA || (MIPS && MACH_LOONGSON64)
---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 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"
depends on TTY
---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"
depends on X86_32 && PCI && INPUT
---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 && TTY
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 && !UML
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 RAW_DRIVER
tristate "RAW driver (/dev/raw/rawN)"
[PATCH] BLOCK: Make it possible to disable the block layer [try #6] Make it possible to disable the block layer. Not all embedded devices require it, some can make do with just JFFS2, NFS, ramfs, etc - none of which require the block layer to be present. This patch does the following: (*) Introduces CONFIG_BLOCK to disable the block layer, buffering and blockdev support. (*) Adds dependencies on CONFIG_BLOCK to any configuration item that controls an item that uses the block layer. This includes: (*) Block I/O tracing. (*) Disk partition code. (*) All filesystems that are block based, eg: Ext3, ReiserFS, ISOFS. (*) The SCSI layer. As far as I can tell, even SCSI chardevs use the block layer to do scheduling. Some drivers that use SCSI facilities - such as USB storage - end up disabled indirectly from this. (*) Various block-based device drivers, such as IDE and the old CDROM drivers. (*) MTD blockdev handling and FTL. (*) JFFS - which uses set_bdev_super(), something it could avoid doing by taking a leaf out of JFFS2's book. (*) Makes most of the contents of linux/blkdev.h, linux/buffer_head.h and linux/elevator.h contingent on CONFIG_BLOCK being set. sector_div() is, however, still used in places, and so is still available. (*) Also made contingent are the contents of linux/mpage.h, linux/genhd.h and parts of linux/fs.h. (*) Makes a number of files in fs/ contingent on CONFIG_BLOCK. (*) Makes mm/bounce.c (bounce buffering) contingent on CONFIG_BLOCK. (*) set_page_dirty() doesn't call __set_page_dirty_buffers() if CONFIG_BLOCK is not enabled. (*) fs/no-block.c is created to hold out-of-line stubs and things that are required when CONFIG_BLOCK is not set: (*) Default blockdev file operations (to give error ENODEV on opening). (*) Makes some /proc changes: (*) /proc/devices does not list any blockdevs. (*) /proc/diskstats and /proc/partitions are contingent on CONFIG_BLOCK. (*) Makes some compat ioctl handling contingent on CONFIG_BLOCK. (*) If CONFIG_BLOCK is not defined, makes sys_quotactl() return -ENODEV if given command other than Q_SYNC or if a special device is specified. (*) In init/do_mounts.c, no reference is made to the blockdev routines if CONFIG_BLOCK is not defined. This does not prohibit NFS roots or JFFS2. (*) The bdflush, ioprio_set and ioprio_get syscalls can now be absent (return error ENOSYS by way of cond_syscall if so). (*) The seclvl_bd_claim() and seclvl_bd_release() security calls do nothing if CONFIG_BLOCK is not set, since they can't then happen. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-10-01 02:45:40 +08:00
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 (1-65536)"
depends on RAW_DRIVER
range 1 65536
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.
config HPET_MMAP_DEFAULT
bool "Enable HPET MMAP access by default"
default y
depends on HPET_MMAP
help
In some hardware implementations, the page containing HPET
registers may also contain other things that shouldn't be
exposed to the user. This option selects the default (if
kernel parameter hpet_mmap is not set) user access to the
registers for applications that require it.
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 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 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 "/dev/port character device"
depends on ISA || PCI
default y
help
Say Y here if you want to support the /dev/port device. The /dev/port
device is similar to /dev/mem, but for I/O ports.
source "drivers/s390/char/Kconfig"
arch/tile: add hypervisor-based character driver for SPI flash ROM The first version of this patch proposed an arch/tile/drivers/ directory, but the consensus was that this was probably a poor choice for a place to group Tilera-specific drivers, and that in any case grouping by platform was discouraged, and grouping by function was preferred. This version of the patch addresses various issues raised in the community, primarily the absence of sysfs integration. The sysfs integration now handles passing information on sector size, page size, and total partition size to userspace as well. In addition, we now use a single "struct cdev" to manage all the partition minor devices, and dynamically discover the correct number of partitions from the hypervisor rather than using a module_param with a default value. This driver has no particular "peer" drivers it can be grouped with. It is sort of like an MTD driver for SPI ROM, but it doesn't group well with the other MTD devices since it relies on hypervisor virtualization to handle many of the irritating aspects of flash ROM management: sector awareness, background read for sub-sector writes, bit examination to determine whether a sector erase needs to be issued, etc. It is in fact more like an EEPROM driver, but the hypervisor virtualization does require a "flush" command if you wish to commit a sector write prior to writing to a different sector, and this is sufficiently different from generic I2C/SPI EEPROMs that as a result it doesn't group well with them either. The simple character device is already in use by a range of Tilera SPI ROM management tools, as well as by customers. In addition, using the simple character device actually simplifies the userspace tools, since they don't need to manage sector erase, background read, etc. This both simplifies the code (since we can uniformly manage plain files and the SPI ROM) as well as makes the user code portable to non-Linux platforms that don't offer the same MTD ioctls. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
2011-06-11 01:07:48 +08:00
config TILE_SROM
tristate "Character-device access via hypervisor to the Tilera SPI ROM"
arch/tile: add hypervisor-based character driver for SPI flash ROM The first version of this patch proposed an arch/tile/drivers/ directory, but the consensus was that this was probably a poor choice for a place to group Tilera-specific drivers, and that in any case grouping by platform was discouraged, and grouping by function was preferred. This version of the patch addresses various issues raised in the community, primarily the absence of sysfs integration. The sysfs integration now handles passing information on sector size, page size, and total partition size to userspace as well. In addition, we now use a single "struct cdev" to manage all the partition minor devices, and dynamically discover the correct number of partitions from the hypervisor rather than using a module_param with a default value. This driver has no particular "peer" drivers it can be grouped with. It is sort of like an MTD driver for SPI ROM, but it doesn't group well with the other MTD devices since it relies on hypervisor virtualization to handle many of the irritating aspects of flash ROM management: sector awareness, background read for sub-sector writes, bit examination to determine whether a sector erase needs to be issued, etc. It is in fact more like an EEPROM driver, but the hypervisor virtualization does require a "flush" command if you wish to commit a sector write prior to writing to a different sector, and this is sufficiently different from generic I2C/SPI EEPROMs that as a result it doesn't group well with them either. The simple character device is already in use by a range of Tilera SPI ROM management tools, as well as by customers. In addition, using the simple character device actually simplifies the userspace tools, since they don't need to manage sector erase, background read, etc. This both simplifies the code (since we can uniformly manage plain files and the SPI ROM) as well as makes the user code portable to non-Linux platforms that don't offer the same MTD ioctls. Signed-off-by: Chris Metcalf <cmetcalf@tilera.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
2011-06-11 01:07:48 +08:00
depends on TILE
default y
---help---
This device provides character-level read-write access
to the SROM, typically via the "0", "1", and "2" devices
in /dev/srom/. The Tilera hypervisor makes the flash
device appear much like a simple EEPROM, and knows
how to partition a single ROM for multiple purposes.
source "drivers/char/xillybus/Kconfig"
endmenu