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|
#
# RTC class/drivers configuration
#
config RTC_LIB
tristate
menuconfig RTC_CLASS
tristate "Real Time Clock"
default n
depends on !S390
select RTC_LIB
help
Generic RTC class support. If you say yes here, you will
be allowed to plug one or more RTCs to your system. You will
probably want to enable one or more of the interfaces below.
This driver can also be built as a module. If so, the module
will be called rtc-core.
if RTC_CLASS
config RTC_HCTOSYS
bool "Set system time from RTC on startup and resume"
depends on RTC_CLASS = y
default y
help
If you say yes here, the system time (wall clock) will be set using
the value read from a specified RTC device. This is useful to avoid
unnecessary fsck runs at boot time, and to network better.
config RTC_HCTOSYS_DEVICE
string "RTC used to set the system time"
depends on RTC_HCTOSYS = y
default "rtc0"
help
The RTC device that will be used to (re)initialize the system
clock, usually rtc0. Initialization is done when the system
starts up, and when it resumes from a low power state. This
device should record time in UTC, since the kernel won't do
timezone correction.
The driver for this RTC device must be loaded before late_initcall
functions run, so it must usually be statically linked.
This clock should be battery-backed, so that it reads the correct
time when the system boots from a power-off state. Otherwise, your
system will need an external clock source (like an NTP server).
If the clock you specify here is not battery backed, it may still
be useful to reinitialize system time when resuming from system
sleep states. Do not specify an RTC here unless it stays powered
during all this system's supported sleep states.
config RTC_DEBUG
bool "RTC debug support"
depends on RTC_CLASS = y
help
Say yes here to enable debugging support in the RTC framework
and individual RTC drivers.
comment "RTC interfaces"
config RTC_INTF_SYSFS
boolean "/sys/class/rtc/rtcN (sysfs)"
depends on SYSFS
default RTC_CLASS
help
Say yes here if you want to use your RTCs using sysfs interfaces,
/sys/class/rtc/rtc0 through /sys/.../rtcN.
If unsure, say Y.
config RTC_INTF_PROC
boolean "/proc/driver/rtc (procfs for rtc0)"
depends on PROC_FS
default RTC_CLASS
help
Say yes here if you want to use your first RTC through the proc
interface, /proc/driver/rtc. Other RTCs will not be available
through that API.
If unsure, say Y.
config RTC_INTF_DEV
boolean "/dev/rtcN (character devices)"
default RTC_CLASS
help
Say yes here if you want to use your RTCs using the /dev
interfaces, which "udev" sets up as /dev/rtc0 through
/dev/rtcN.
You may want to set up a symbolic link so one of these
can be accessed as /dev/rtc, which is a name
expected by "hwclock" and some other programs. Recent
versions of "udev" are known to set up the symlink for you.
If unsure, say Y.
config RTC_INTF_DEV_UIE_EMUL
bool "RTC UIE emulation on dev interface"
depends on RTC_INTF_DEV
help
Provides an emulation for RTC_UIE if the underlying rtc chip
driver does not expose RTC_UIE ioctls. Those requests generate
once-per-second update interrupts, used for synchronization.
The emulation code will read the time from the hardware
clock several times per second, please enable this option
only if you know that you really need it.
config RTC_DRV_TEST
tristate "Test driver/device"
help
If you say yes here you get support for the
RTC test driver. It's a software RTC which can be
used to test the RTC subsystem APIs. It gets
the time from the system clock.
You want this driver only if you are doing development
on the RTC subsystem. Please read the source code
for further details.
This driver can also be built as a module. If so, the module
will be called rtc-test.
comment "I2C RTC drivers"
depends on I2C
if I2C
config RTC_DRV_DS1307
tristate "Dallas/Maxim DS1307/37/38/39/40, ST M41T00"
help
If you say yes here you get support for various compatible RTC
chips (often with battery backup) connected with I2C. This driver
should handle DS1307, DS1337, DS1338, DS1339, DS1340, ST M41T00,
and probably other chips. In some cases the RTC must already
have been initialized (by manufacturing or a bootloader).
The first seven registers on these chips hold an RTC, and other
registers may add features such as NVRAM, a trickle charger for
the RTC/NVRAM backup power, and alarms. NVRAM is visible in
sysfs, but other chip features may not be available.
This driver can also be built as a module. If so, the module
will be called rtc-ds1307.
config RTC_DRV_DS1374
tristate "Dallas/Maxim DS1374"
depends on RTC_CLASS && I2C
help
If you say yes here you get support for Dallas Semiconductor
DS1374 real-time clock chips. If an interrupt is associated
with the device, the alarm functionality is supported.
This driver can also be built as a module. If so, the module
will be called rtc-ds1374.
config RTC_DRV_DS1672
tristate "Dallas/Maxim DS1672"
help
If you say yes here you get support for the
Dallas/Maxim DS1672 timekeeping chip.
This driver can also be built as a module. If so, the module
will be called rtc-ds1672.
config RTC_DRV_MAX6900
tristate "Maxim MAX6900"
help
If you say yes here you will get support for the
Maxim MAX6900 I2C RTC chip.
This driver can also be built as a module. If so, the module
will be called rtc-max6900.
config RTC_DRV_RS5C372
tristate "Ricoh R2025S/D, RS5C372A/B, RV5C386, RV5C387A"
help
If you say yes here you get support for the
Ricoh R2025S/D, RS5C372A, RS5C372B, RV5C386, and RV5C387A RTC chips.
This driver can also be built as a module. If so, the module
will be called rtc-rs5c372.
config RTC_DRV_ISL1208
tristate "Intersil ISL1208"
help
If you say yes here you get support for the
Intersil ISL1208 RTC chip.
This driver can also be built as a module. If so, the module
will be called rtc-isl1208.
config RTC_DRV_X1205
tristate "Xicor/Intersil X1205"
help
If you say yes here you get support for the
Xicor/Intersil X1205 RTC chip.
This driver can also be built as a module. If so, the module
will be called rtc-x1205.
config RTC_DRV_PCF8563
tristate "Philips PCF8563/Epson RTC8564"
help
If you say yes here you get support for the
Philips PCF8563 RTC chip. The Epson RTC8564
should work as well.
This driver can also be built as a module. If so, the module
will be called rtc-pcf8563.
config RTC_DRV_PCF8583
tristate "Philips PCF8583"
help
If you say yes here you get support for the Philips PCF8583
RTC chip found on Acorn RiscPCs. This driver supports the
platform specific method of retrieving the current year from
the RTC's SRAM. It will work on other platforms with the same
chip, but the year will probably have to be tweaked.
This driver can also be built as a module. If so, the module
will be called rtc-pcf8583.
config RTC_DRV_M41T80
tristate "ST M41T65/M41T80/81/82/83/84/85/87"
help
If you say Y here you will get support for the ST M41T60
and M41T80 RTC chips series. Currently, the following chips are
supported: M41T65, M41T80, M41T81, M41T82, M41T83, M41ST84,
M41ST85, and M41ST87.
This driver can also be built as a module. If so, the module
will be called rtc-m41t80.
config RTC_DRV_M41T80_WDT
bool "ST M41T65/M41T80 series RTC watchdog timer"
depends on RTC_DRV_M41T80
help
If you say Y here you will get support for the
watchdog timer in the ST M41T60 and M41T80 RTC chips series.
config RTC_DRV_DM355EVM
tristate "TI DaVinci DM355 EVM RTC"
depends on MFD_DM355EVM_MSP
help
Supports the RTC firmware in the MSP430 on the DM355 EVM.
config RTC_DRV_TWL92330
boolean "TI TWL92330/Menelaus"
depends on MENELAUS
help
If you say yes here you get support for the RTC on the
TWL92330 "Menelaus" power management chip, used with OMAP2
platforms. The support is integrated with the rest of
the Menelaus driver; it's not separate module.
config RTC_DRV_TWL4030
tristate "TI TWL4030/TWL5030/TPS659x0"
depends on RTC_CLASS && TWL4030_CORE
help
If you say yes here you get support for the RTC on the
TWL4030 family chips, used mostly with OMAP3 platforms.
This driver can also be built as a module. If so, the module
will be called rtc-twl4030.
config RTC_DRV_S35390A
tristate "Seiko Instruments S-35390A"
select BITREVERSE
help
If you say yes here you will get support for the Seiko
Instruments S-35390A.
This driver can also be built as a module. If so the module
will be called rtc-s35390a.
config RTC_DRV_FM3130
tristate "Ramtron FM3130"
help
If you say Y here you will get support for the
Ramtron FM3130 RTC chips.
Ramtron FM3130 is a chip with two separate devices inside,
RTC clock and FRAM. This driver provides only RTC functionality.
This driver can also be built as a module. If so the module
will be called rtc-fm3130.
config RTC_DRV_RX8581
tristate "Epson RX-8581"
help
If you say yes here you will get support for the Epson RX-8581.
This driver can also be built as a module. If so the module
will be called rtc-rx8581.
endif # I2C
comment "SPI RTC drivers"
if SPI_MASTER
config RTC_DRV_M41T94
tristate "ST M41T94"
help
If you say yes here you will get support for the
ST M41T94 SPI RTC chip.
This driver can also be built as a module. If so, the module
will be called rtc-m41t94.
config RTC_DRV_DS1305
tristate "Dallas/Maxim DS1305/DS1306"
help
Select this driver to get support for the Dallas/Maxim DS1305
and DS1306 real time clock chips. These support a trickle
charger, alarms, and NVRAM in addition to the clock.
This driver can also be built as a module. If so, the module
will be called rtc-ds1305.
config RTC_DRV_DS1390
tristate "Dallas/Maxim DS1390/93/94"
help
If you say yes here you get support for the
Dallas/Maxim DS1390/93/94 chips.
This driver only supports the RTC feature, and not other chip
features such as alarms and trickle charging.
This driver can also be built as a module. If so, the module
will be called rtc-ds1390.
config RTC_DRV_MAX6902
tristate "Maxim MAX6902"
help
If you say yes here you will get support for the
Maxim MAX6902 SPI RTC chip.
This driver can also be built as a module. If so, the module
will be called rtc-max6902.
config RTC_DRV_R9701
tristate "Epson RTC-9701JE"
help
If you say yes here you will get support for the
Epson RTC-9701JE SPI RTC chip.
This driver can also be built as a module. If so, the module
will be called rtc-r9701.
config RTC_DRV_RS5C348
tristate "Ricoh RS5C348A/B"
help
If you say yes here you get support for the
Ricoh RS5C348A and RS5C348B RTC chips.
This driver can also be built as a module. If so, the module
will be called rtc-rs5c348.
config RTC_DRV_DS3234
tristate "Maxim/Dallas DS3234"
help
If you say yes here you get support for the
Maxim/Dallas DS3234 SPI RTC chip.
This driver can also be built as a module. If so, the module
will be called rtc-ds3234.
endif # SPI_MASTER
comment "Platform RTC drivers"
# this 'CMOS' RTC driver is arch dependent because <asm-generic/rtc.h>
# requires <asm/mc146818rtc.h> defining CMOS_READ/CMOS_WRITE, and a
# global rtc_lock ... it's not yet just another platform_device.
config RTC_DRV_CMOS
tristate "PC-style 'CMOS'"
depends on X86 || ALPHA || ARM || M32R || ATARI || PPC || MIPS || SPARC64
default y if X86
help
Say "yes" here to get direct support for the real time clock
found in every PC or ACPI-based system, and some other boards.
Specifically the original MC146818, compatibles like those in
PC south bridges, the DS12887 or M48T86, some multifunction
or LPC bus chips, and so on.
Your system will need to define the platform device used by
this driver, otherwise it won't be accessible. This means
you can safely enable this driver if you don't know whether
or not your board has this kind of hardware.
This driver can also be built as a module. If so, the module
will be called rtc-cmos.
config RTC_DRV_DS1216
tristate "Dallas DS1216"
depends on SNI_RM
help
If you say yes here you get support for the Dallas DS1216 RTC chips.
config RTC_DRV_DS1286
tristate "Dallas DS1286"
help
If you say yes here you get support for the Dallas DS1286 RTC chips.
config RTC_DRV_DS1302
tristate "Dallas DS1302"
depends on SH_SECUREEDGE5410
help
If you say yes here you get support for the Dallas DS1302 RTC chips.
config RTC_DRV_DS1511
tristate "Dallas DS1511"
depends on RTC_CLASS
help
If you say yes here you get support for the
Dallas DS1511 timekeeping/watchdog chip.
This driver can also be built as a module. If so, the module
will be called rtc-ds1511.
config RTC_DRV_DS1553
tristate "Maxim/Dallas DS1553"
help
If you say yes here you get support for the
Maxim/Dallas DS1553 timekeeping chip.
This driver can also be built as a module. If so, the module
will be called rtc-ds1553.
config RTC_DRV_DS1742
tristate "Maxim/Dallas DS1742/1743"
help
If you say yes here you get support for the
Maxim/Dallas DS1742/1743 timekeeping chip.
This driver can also be built as a module. If so, the module
will be called rtc-ds1742.
config RTC_DRV_STK17TA8
tristate "Simtek STK17TA8"
depends on RTC_CLASS
help
If you say yes here you get support for the
Simtek STK17TA8 timekeeping chip.
This driver can also be built as a module. If so, the module
will be called rtc-stk17ta8.
config RTC_DRV_M48T86
tristate "ST M48T86/Dallas DS12887"
help
If you say Y here you will get support for the
ST M48T86 and Dallas DS12887 RTC chips.
This driver can also be built as a module. If so, the module
will be called rtc-m48t86.
config RTC_DRV_M48T35
tristate "ST M48T35"
help
If you say Y here you will get support for the
ST M48T35 RTC chip.
This driver can also be built as a module, if so, the module
will be called "rtc-m48t35".
config RTC_DRV_M48T59
tristate "ST M48T59/M48T08/M48T02"
help
If you say Y here you will get support for the
ST M48T59 RTC chip and compatible ST M48T08 and M48T02.
These chips are usually found in Sun SPARC and UltraSPARC
workstations.
This driver can also be built as a module, if so, the module
will be called "rtc-m48t59".
config RTC_DRV_BQ4802
tristate
|