2 # RTC class/drivers configuration
9 tristate "Real Time Clock"
14 Generic RTC class support. If you say yes here, you will
15 be allowed to plug one or more RTCs to your system. You will
16 probably want to enable one or more of the interfaces below.
18 This driver can also be built as a module. If so, the module
19 will be called rtc-core.
24 comment "Conflicting RTC option has been selected, check GEN_RTC and RTC"
28 bool "Set system time from RTC on startup and resume"
29 depends on RTC_CLASS = y
32 If you say yes here, the system time (wall clock) will be set using
33 the value read from a specified RTC device. This is useful to avoid
34 unnecessary fsck runs at boot time, and to network better.
36 config RTC_HCTOSYS_DEVICE
37 string "RTC used to set the system time"
38 depends on RTC_HCTOSYS = y
41 The RTC device that will be used to (re)initialize the system
42 clock, usually rtc0. Initialization is done when the system
43 starts up, and when it resumes from a low power state. This
44 device should record time in UTC, since the kernel won't do
47 The driver for this RTC device must be loaded before late_initcall
48 functions run, so it must usually be statically linked.
50 This clock should be battery-backed, so that it reads the correct
51 time when the system boots from a power-off state. Otherwise, your
52 system will need an external clock source (like an NTP server).
54 If the clock you specify here is not battery backed, it may still
55 be useful to reinitialize system time when resuming from system
56 sleep states. Do not specify an RTC here unless it stays powered
57 during all this system's supported sleep states.
60 bool "RTC debug support"
61 depends on RTC_CLASS = y
63 Say yes here to enable debugging support in the RTC framework
64 and individual RTC drivers.
66 comment "RTC interfaces"
69 boolean "/sys/class/rtc/rtcN (sysfs)"
73 Say yes here if you want to use your RTCs using sysfs interfaces,
74 /sys/class/rtc/rtc0 through /sys/.../rtcN.
76 This driver can also be built as a module. If so, the module
77 will be called rtc-sysfs.
80 boolean "/proc/driver/rtc (procfs for rtc0)"
84 Say yes here if you want to use your first RTC through the proc
85 interface, /proc/driver/rtc. Other RTCs will not be available
88 This driver can also be built as a module. If so, the module
89 will be called rtc-proc.
92 boolean "/dev/rtcN (character devices)"
95 Say yes here if you want to use your RTCs using the /dev
96 interfaces, which "udev" sets up as /dev/rtc0 through
97 /dev/rtcN. You may want to set up a symbolic link so one
98 of these can be accessed as /dev/rtc, which is a name
99 expected by "hwclock" and some other programs.
101 This driver can also be built as a module. If so, the module
102 will be called rtc-dev.
104 config RTC_INTF_DEV_UIE_EMUL
105 bool "RTC UIE emulation on dev interface"
106 depends on RTC_INTF_DEV
108 Provides an emulation for RTC_UIE if the underlying rtc chip
109 driver does not expose RTC_UIE ioctls. Those requests generate
110 once-per-second update interrupts, used for synchronization.
113 tristate "Test driver/device"
115 If you say yes here you get support for the
116 RTC test driver. It's a software RTC which can be
117 used to test the RTC subsystem APIs. It gets
118 the time from the system clock.
119 You want this driver only if you are doing development
120 on the RTC subsystem. Please read the source code
123 This driver can also be built as a module. If so, the module
124 will be called rtc-test.
126 comment "I2C RTC drivers"
131 config RTC_DRV_DS1307
132 tristate "Dallas/Maxim DS1307/37/38/39/40, ST M41T00"
134 If you say yes here you get support for various compatible RTC
135 chips (often with battery backup) connected with I2C. This driver
136 should handle DS1307, DS1337, DS1338, DS1339, DS1340, ST M41T00,
137 and probably other chips. In some cases the RTC must already
138 have been initialized (by manufacturing or a bootloader).
140 The first seven registers on these chips hold an RTC, and other
141 registers may add features such as NVRAM, a trickle charger for
142 the RTC/NVRAM backup power, and alarms. NVRAM is visible in
143 sysfs, but other chip features may not be available.
145 This driver can also be built as a module. If so, the module
146 will be called rtc-ds1307.
148 config RTC_DRV_DS1374
149 tristate "Dallas/Maxim DS1374"
150 depends on RTC_CLASS && I2C
152 If you say yes here you get support for Dallas Semiconductor
153 DS1374 real-time clock chips. If an interrupt is associated
154 with the device, the alarm functionality is supported.
156 This driver can also be built as a module. If so, the module
157 will be called rtc-ds1374.
159 config RTC_DRV_DS1672
160 tristate "Dallas/Maxim DS1672"
162 If you say yes here you get support for the
163 Dallas/Maxim DS1672 timekeeping chip.
165 This driver can also be built as a module. If so, the module
166 will be called rtc-ds1672.
168 config RTC_DRV_MAX6900
169 tristate "Maxim MAX6900"
171 If you say yes here you will get support for the
172 Maxim MAX6900 I2C RTC chip.
174 This driver can also be built as a module. If so, the module
175 will be called rtc-max6900.
177 config RTC_DRV_RS5C372
178 tristate "Ricoh RS5C372A/B, RV5C386, RV5C387A"
180 If you say yes here you get support for the
181 Ricoh RS5C372A, RS5C372B, RV5C386, and RV5C387A RTC chips.
183 This driver can also be built as a module. If so, the module
184 will be called rtc-rs5c372.
186 config RTC_DRV_ISL1208
187 tristate "Intersil ISL1208"
189 If you say yes here you get support for the
190 Intersil ISL1208 RTC chip.
192 This driver can also be built as a module. If so, the module
193 will be called rtc-isl1208.
196 tristate "Xicor/Intersil X1205"
198 If you say yes here you get support for the
199 Xicor/Intersil X1205 RTC chip.
201 This driver can also be built as a module. If so, the module
202 will be called rtc-x1205.
204 config RTC_DRV_PCF8563
205 tristate "Philips PCF8563/Epson RTC8564"
207 If you say yes here you get support for the
208 Philips PCF8563 RTC chip. The Epson RTC8564
211 This driver can also be built as a module. If so, the module
212 will be called rtc-pcf8563.
214 config RTC_DRV_PCF8583
215 tristate "Philips PCF8583"
217 If you say yes here you get support for the Philips PCF8583
218 RTC chip found on Acorn RiscPCs. This driver supports the
219 platform specific method of retrieving the current year from
220 the RTC's SRAM. It will work on other platforms with the same
221 chip, but the year will probably have to be tweaked.
223 This driver can also be built as a module. If so, the module
224 will be called rtc-pcf8583.
226 config RTC_DRV_M41T80
227 tristate "ST M41T80/81/82/83/84/85/87"
229 If you say Y here you will get support for the
230 ST M41T80 RTC chips series. Currently following chips are
231 supported: M41T80, M41T81, M41T82, M41T83, M41ST84, M41ST85
234 This driver can also be built as a module. If so, the module
235 will be called rtc-m41t80.
237 config RTC_DRV_M41T80_WDT
238 bool "ST M41T80 series RTC watchdog timer"
239 depends on RTC_DRV_M41T80
241 If you say Y here you will get support for the
242 watchdog timer in ST M41T80 RTC chips series.
244 config RTC_DRV_TWL92330
245 boolean "TI TWL92330/Menelaus"
248 If you say yes here you get support for the RTC on the
249 TWL92330 "Menelaus" power management chip, used with OMAP2
250 platforms. The support is integrated with the rest of
251 the Menelaus driver; it's not separate module.
253 config RTC_DRV_TWL4030
254 tristate "OMAP TWL4030 Real Time Clock"
255 depends on RTC_CLASS && TWL4030_CORE
257 If you say yes here you get support for internal Real-Time
258 Clock of TWL4030 chip.
260 This driver can also be built as a module. If so, the module
261 will be called rtc-twl4030.
263 config RTC_DRV_S35390A
264 tristate "Seiko Instruments S-35390A"
267 If you say yes here you will get support for the Seiko
268 Instruments S-35390A.
270 This driver can also be built as a module. If so the module
271 will be called rtc-s35390a.
275 comment "SPI RTC drivers"
279 config RTC_DRV_MAX6902
280 tristate "Maxim MAX6902"
282 If you say yes here you will get support for the
283 Maxim MAX6902 SPI RTC chip.
285 This driver can also be built as a module. If so, the module
286 will be called rtc-max6902.
289 tristate "Epson RTC-9701JE"
291 If you say yes here you will get support for the
292 Epson RTC-9701JE SPI RTC chip.
294 This driver can also be built as a module. If so, the module
295 will be called rtc-r9701.
297 config RTC_DRV_RS5C348
298 tristate "Ricoh RS5C348A/B"
300 If you say yes here you get support for the
301 Ricoh RS5C348A and RS5C348B RTC chips.
303 This driver can also be built as a module. If so, the module
304 will be called rtc-rs5c348.
308 comment "Platform RTC drivers"
310 # this 'CMOS' RTC driver is arch dependent because <asm-generic/rtc.h>
311 # requires <asm/mc146818rtc.h> defining CMOS_READ/CMOS_WRITE, and a
312 # global rtc_lock ... it's not yet just another platform_device.
315 tristate "PC-style 'CMOS'"
316 depends on X86 || ALPHA || ARM || M32R || ATARI || PPC || MIPS
318 Say "yes" here to get direct support for the real time clock
319 found in every PC or ACPI-based system, and some other boards.
320 Specifically the original MC146818, compatibles like those in
321 PC south bridges, the DS12887 or M48T86, some multifunction
322 or LPC bus chips, and so on.
324 Your system will need to define the platform device used by
325 this driver, otherwise it won't be accessible. This means
326 you can safely enable this driver if you don't know whether
327 or not your board has this kind of hardware.
329 This driver can also be built as a module. If so, the module
330 will be called rtc-cmos.
332 config RTC_DRV_DS1216
333 tristate "Dallas DS1216"
336 If you say yes here you get support for the Dallas DS1216 RTC chips.
338 config RTC_DRV_DS1302
339 tristate "Dallas DS1302"
340 depends on SH_SECUREEDGE5410
342 If you say yes here you get support for the Dallas DS1302 RTC chips.
344 config RTC_DRV_DS1511
345 tristate "Dallas DS1511"
348 If you say yes here you get support for the
349 Dallas DS1511 timekeeping/watchdog chip.
351 This driver can also be built as a module. If so, the module
352 will be called rtc-ds1511.
354 config RTC_DRV_DS1553
355 tristate "Maxim/Dallas DS1553"
357 If you say yes here you get support for the
358 Maxim/Dallas DS1553 timekeeping chip.
360 This driver can also be built as a module. If so, the module
361 will be called rtc-ds1553.
363 config RTC_DRV_DS1742
364 tristate "Maxim/Dallas DS1742/1743"
366 If you say yes here you get support for the
367 Maxim/Dallas DS1742/1743 timekeeping chip.
369 This driver can also be built as a module. If so, the module
370 will be called rtc-ds1742.
372 config RTC_DRV_STK17TA8
373 tristate "Simtek STK17TA8"
376 If you say yes here you get support for the
377 Simtek STK17TA8 timekeeping chip.
379 This driver can also be built as a module. If so, the module
380 will be called rtc-stk17ta8.
382 config RTC_DRV_M48T86
383 tristate "ST M48T86/Dallas DS12887"
385 If you say Y here you will get support for the
386 ST M48T86 and Dallas DS12887 RTC chips.
388 This driver can also be built as a module. If so, the module
389 will be called rtc-m48t86.
391 config RTC_DRV_M48T59
394 If you say Y here you will get support for the
397 This driver can also be built as a module, if so, the module
398 will be called "rtc-m48t59".
401 tristate "EM Microelectronic V3020"
403 If you say yes here you will get support for the
404 EM Microelectronic v3020 RTC chip.
406 This driver can also be built as a module. If so, the module
407 will be called rtc-v3020.
409 comment "on-CPU RTC drivers"
413 depends on ARCH_OMAP15XX || ARCH_OMAP16XX || ARCH_OMAP730
415 Say "yes" here to support the real time clock on TI OMAP1 chips.
416 This driver can also be built as a module called rtc-omap.
419 tristate "Samsung S3C series SoC RTC"
420 depends on ARCH_S3C2410
422 RTC (Realtime Clock) driver for the clock inbuilt into the
423 Samsung S3C24XX series of SoCs. This can provide periodic
424 interrupt rates from 1Hz to 64Hz for user programs, and
427 The driver currently supports the common features on all the
428 S3C24XX range, such as the S3C2410, S3C2412, S3C2413, S3C2440
431 This driver can also be build as a module. If so, the module
432 will be called rtc-s3c.
434 config RTC_DRV_EP93XX
435 tristate "Cirrus Logic EP93XX"
436 depends on ARCH_EP93XX
438 If you say yes here you get support for the
439 RTC embedded in the Cirrus Logic EP93XX processors.
441 This driver can also be built as a module. If so, the module
442 will be called rtc-ep93xx.
444 config RTC_DRV_SA1100
445 tristate "SA11x0/PXA2xx"
446 depends on ARCH_SA1100 || ARCH_PXA
448 If you say Y here you will get access to the real time clock
449 built into your SA11x0 or PXA2xx CPU.
451 To compile this driver as a module, choose M here: the
452 module will be called rtc-sa1100.
455 tristate "SuperH On-Chip RTC"
456 depends on RTC_CLASS && SUPERH
458 Say Y here to enable support for the on-chip RTC found in
459 most SuperH processors.
461 To compile this driver as a module, choose M here: the
462 module will be called rtc-sh.
464 config RTC_DRV_VR41XX
465 tristate "NEC VR41XX"
466 depends on CPU_VR41XX
468 If you say Y here you will get access to the real time clock
469 built into your NEC VR41XX CPU.
471 To compile this driver as a module, choose M here: the
472 module will be called rtc-vr41xx.
475 tristate "ARM AMBA PL031 RTC"
478 If you say Y here you will get access to ARM AMBA
479 PrimeCell PL031 RTC found on certain ARM SOCs.
481 To compile this driver as a module, choose M here: the
482 module will be called rtc-pl031.
484 config RTC_DRV_AT32AP700X
485 tristate "AT32AP700X series RTC"
486 depends on PLATFORM_AT32AP
488 Driver for the internal RTC (Realtime Clock) on Atmel AVR32
489 AT32AP700x family processors.
491 config RTC_DRV_AT91RM9200
492 tristate "AT91RM9200 or AT91SAM9RL"
493 depends on ARCH_AT91RM9200 || ARCH_AT91SAM9RL
495 Driver for the internal RTC (Realtime Clock) module found on
496 Atmel AT91RM9200's and AT91SAM9RL chips. On SAM9RL chips
497 this is powered by the backup power supply.
499 config RTC_DRV_AT91SAM9
501 depends on ARCH_AT91 && !(ARCH_AT91RM9200 || ARCH_AT91X40)
503 RTC driver for the Atmel AT91SAM9x internal RTT (Real Time Timer).
504 These timers are powered by the backup power supply (such as a
505 small coin cell battery), but do not need to be used as RTCs.
507 (On AT91SAM9rl chips you probably want to use the dedicated RTC
508 module and leave the RTT available for other uses.)
510 config RTC_DRV_AT91SAM9_RTT
514 prompt "RTT module Number" if ARCH_AT91SAM9263
515 depends on RTC_DRV_AT91SAM9
517 More than one RTT module is available. You can choose which
518 one will be used as an RTC. The default of zero is normally
519 OK to use, though some systems use that for non-RTC purposes.
521 config RTC_DRV_AT91SAM9_GPBR
523 range 0 3 if !ARCH_AT91SAM9263
524 range 0 15 if ARCH_AT91SAM9263
526 prompt "Backup Register Number"
527 depends on RTC_DRV_AT91SAM9
529 The RTC driver needs to use one of the General Purpose Backup
530 Registers (GPBRs) as well as the RTT. You can choose which one
531 will be used. The default of zero is normally OK to use, but
532 on some systems other software needs to use that register.
535 tristate "Blackfin On-Chip RTC"
538 If you say yes here you will get support for the
539 Blackfin On-Chip Real Time Clock.
541 This driver can also be built as a module. If so, the module
542 will be called rtc-bfin.
544 config RTC_DRV_RS5C313
545 tristate "Ricoh RS5C313"
546 depends on SH_LANDISK
548 If you say yes here you get support for the Ricoh RS5C313 RTC chips.