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|
#
# RTC class/drivers configuration
#
config RTC_LIB
bool
menuconfig RTC_CLASS
bool "Real Time Clock"
default n
depends on !S390 && !UML
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.
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_88PM860X
tristate "Marvell 88PM860x"
depends on RTC_CLASS && I2C && MFD_88PM860X
help
If you say yes here you get support for RTC function in Marvell
88PM860x chips.
This driver can also be built as a module. If so, the module
will be called rtc-88pm860x.
config RTC_DRV_DS1307
tristate "Dallas/Maxim DS1307/37/38/39/40, ST M41T00, EPSON RX-8025"
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,
EPSON RX-8025 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_DS3232
tristate "Dallas/Maxim DS3232"
depends on RTC_CLASS && I2C
help
If you say yes here you get support for Dallas Semiconductor
DS3232 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-ds3232.
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_MAX8925
tristate "Maxim MAX8925"
depends on MFD_MAX8925
help
If you say yes here you will get support for the
RTC of Maxim MAX8925 PMIC.
This driver can also be built as a module. If so, the module
will be called rtc-max8925.
config RTC_DRV_MAX8998
tristate "Maxim MAX8998"
depends on MFD_MAX8998
help
If you say yes here you will get support for the
RTC of Maxim MAX8998 PMIC.
This driver can also be built as a module. If so, the module
will be called rtc-max8998.
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_ISL12022
tristate "Intersil ISL12022"
help
If you say yes here you get support for the
Intersil ISL12022 RTC chip.
This driver can also be built as a module. If so, the module
will be called rtc-isl12022.
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 M41T62/65/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: M41T62, 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_BQ32K
tristate "TI BQ32000"
|