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 bool "Set system time from RTC on startup and resume"
25 depends on RTC_CLASS = y
28 If you say yes here, the system time (wall clock) will be set using
29 the value read from a specified RTC device. This is useful to avoid
30 unnecessary fsck runs at boot time, and to network better.
32 config RTC_HCTOSYS_DEVICE
33 string "RTC used to set the system time"
34 depends on RTC_HCTOSYS = y
37 The RTC device that will be used to (re)initialize the system
38 clock, usually rtc0. Initialization is done when the system
39 starts up, and when it resumes from a low power state. This
40 device should record time in UTC, since the kernel won't do
43 The driver for this RTC device must be loaded before late_initcall
44 functions run, so it must usually be statically linked.
46 This clock should be battery-backed, so that it reads the correct
47 time when the system boots from a power-off state. Otherwise, your
48 system will need an external clock source (like an NTP server).
50 If the clock you specify here is not battery backed, it may still
51 be useful to reinitialize system time when resuming from system
52 sleep states. Do not specify an RTC here unless it stays powered
53 during all this system's supported sleep states.
56 bool "RTC debug support"
57 depends on RTC_CLASS = y
59 Say yes here to enable debugging support in the RTC framework
60 and individual RTC drivers.
62 comment "RTC interfaces"
65 boolean "/sys/class/rtc/rtcN (sysfs)"
69 Say yes here if you want to use your RTCs using sysfs interfaces,
70 /sys/class/rtc/rtc0 through /sys/.../rtcN.
72 This driver can also be built as a module. If so, the module
73 will be called rtc-sysfs.
76 boolean "/proc/driver/rtc (procfs for rtc0)"
80 Say yes here if you want to use your first RTC through the proc
81 interface, /proc/driver/rtc. Other RTCs will not be available
84 This driver can also be built as a module. If so, the module
85 will be called rtc-proc.
88 boolean "/dev/rtcN (character devices)"
91 Say yes here if you want to use your RTCs using the /dev
92 interfaces, which "udev" sets up as /dev/rtc0 through
93 /dev/rtcN. You may want to set up a symbolic link so one
94 of these can be accessed as /dev/rtc, which is a name
95 expected by "hwclock" and some other programs.
97 This driver can also be built as a module. If so, the module
98 will be called rtc-dev.
100 config RTC_INTF_DEV_UIE_EMUL
101 bool "RTC UIE emulation on dev interface"
102 depends on RTC_INTF_DEV
104 Provides an emulation for RTC_UIE if the underlying rtc chip
105 driver does not expose RTC_UIE ioctls. Those requests generate
106 once-per-second update interrupts, used for synchronization.
109 tristate "Test driver/device"
111 If you say yes here you get support for the
112 RTC test driver. It's a software RTC which can be
113 used to test the RTC subsystem APIs. It gets
114 the time from the system clock.
115 You want this driver only if you are doing development
116 on the RTC subsystem. Please read the source code
119 This driver can also be built as a module. If so, the module
120 will be called rtc-test.
122 comment "I2C RTC drivers"
127 config RTC_DRV_DS1307
128 tristate "Dallas/Maxim DS1307/37/38/39/40, ST M41T00"
130 If you say yes here you get support for various compatible RTC
131 chips (often with battery backup) connected with I2C. This driver
132 should handle DS1307, DS1337, DS1338, DS1339, DS1340, ST M41T00,
133 and probably other chips. In some cases the RTC must already
134 have been initialized (by manufacturing or a bootloader).
136 The first seven registers on these chips hold an RTC, and other
137 registers may add features such as NVRAM, a trickle charger for
138 the RTC/NVRAM backup power, and alarms. NVRAM is visible in
139 sysfs, but other chip features may not be available.
141 This driver can also be built as a module. If so, the module
142 will be called rtc-ds1307.
144 config RTC_DRV_DS1374
145 tristate "Dallas/Maxim DS1374"
146 depends on RTC_CLASS && I2C
148 If you say yes here you get support for Dallas Semiconductor
149 DS1374 real-time clock chips. If an interrupt is associated
150 with the device, the alarm functionality is supported.
152 This driver can also be built as a module. If so, the module
153 will be called rtc-ds1374.
155 config RTC_DRV_DS1672
156 tristate "Dallas/Maxim DS1672"
158 If you say yes here you get support for the
159 Dallas/Maxim DS1672 timekeeping chip.
161 This driver can also be built as a module. If so, the module
162 will be called rtc-ds1672.
164 config RTC_DRV_MAX6900
165 tristate "Maxim MAX6900"
167 If you say yes here you will get support for the
168 Maxim MAX6900 I2C RTC chip.
170 This driver can also be built as a module. If so, the module
171 will be called rtc-max6900.
173 config RTC_DRV_RS5C372
174 tristate "Ricoh RS5C372A/B, RV5C386, RV5C387A"
176 If you say yes here you get support for the
177 Ricoh RS5C372A, RS5C372B, RV5C386, and RV5C387A RTC chips.
179 This driver can also be built as a module. If so, the module
180 will be called rtc-rs5c372.
182 config RTC_DRV_ISL1208
183 tristate "Intersil ISL1208"
185 If you say yes here you get support for the
186 Intersil ISL1208 RTC chip.
188 This driver can also be built as a module. If so, the module
189 will be called rtc-isl1208.
192 tristate "Xicor/Intersil X1205"
194 If you say yes here you get support for the
195 Xicor/Intersil X1205 RTC chip.
197 This driver can also be built as a module. If so, the module
198 will be called rtc-x1205.
200 config RTC_DRV_PCF8563
201 tristate "Philips PCF8563/Epson RTC8564"
203 If you say yes here you get support for the
204 Philips PCF8563 RTC chip. The Epson RTC8564
207 This driver can also be built as a module. If so, the module
208 will be called rtc-pcf8563.
210 config RTC_DRV_PCF8583
211 tristate "Philips PCF8583"
213 If you say yes here you get support for the Philips PCF8583
214 RTC chip found on Acorn RiscPCs. This driver supports the
215 platform specific method of retrieving the current year from
216 the RTC's SRAM. It will work on other platforms with the same
217 chip, but the year will probably have to be tweaked.
219 This driver can also be built as a module. If so, the module
220 will be called rtc-pcf8583.
222 config RTC_DRV_M41T80
223 tristate "ST M41T80/81/82/83/84/85/87"
225 If you say Y here you will get support for the
226 ST M41T80 RTC chips series. Currently following chips are
227 supported: M41T80, M41T81, M41T82, M41T83, M41ST84, M41ST85
230 This driver can also be built as a module. If so, the module
231 will be called rtc-m41t80.
233 config RTC_DRV_M41T80_WDT
234 bool "ST M41T80 series RTC watchdog timer"
235 depends on RTC_DRV_M41T80
237 If you say Y here you will get support for the
238 watchdog timer in ST M41T80 RTC chips series.
240 config RTC_DRV_TWL92330
241 boolean "TI TWL92330/Menelaus"
244 If you say yes here you get support for the RTC on the
245 TWL92330 "Menelaus" power management chip, used with OMAP2
246 platforms. The support is integrated with the rest of
247 the Menelaus driver; it's not separate module.
249 config RTC_DRV_S35390A
250 tristate "Seiko Instruments S-35390A"
253 If you say yes here you will get support for the Seiko
254 Instruments S-35390A.
256 This driver can also be built as a module. If so the module
257 will be called rtc-s35390a.
259 config RTC_DRV_FM3130
260 tristate "Ramtron FM3130"
262 If you say Y here you will get support for the
263 Ramtron FM3130 RTC chips.
264 Ramtron FM3130 is a chip with two separate devices inside,
265 RTC clock and FRAM. This driver provides only RTC functionality.
267 This driver can also be built as a module. If so the module
268 will be called rtc-fm3130.
272 comment "SPI RTC drivers"
276 config RTC_DRV_M41T94
279 If you say yes here you will get support for the
280 ST M41T94 SPI RTC chip.
282 This driver can also be built as a module. If so, the module
283 will be called rtc-m41t94.
285 config RTC_DRV_MAX6902
286 tristate "Maxim MAX6902"
288 If you say yes here you will get support for the
289 Maxim MAX6902 SPI RTC chip.
291 This driver can also be built as a module. If so, the module
292 will be called rtc-max6902.
295 tristate "Epson RTC-9701JE"
297 If you say yes here you will get support for the
298 Epson RTC-9701JE SPI RTC chip.
300 This driver can also be built as a module. If so, the module
301 will be called rtc-r9701.
303 config RTC_DRV_RS5C348
304 tristate "Ricoh RS5C348A/B"
306 If you say yes here you get support for the
307 Ricoh RS5C348A and RS5C348B RTC chips.
309 This driver can also be built as a module. If so, the module
310 will be called rtc-rs5c348.
314 comment "Platform RTC drivers"
316 # this 'CMOS' RTC driver is arch dependent because <asm-generic/rtc.h>
317 # requires <asm/mc146818rtc.h> defining CMOS_READ/CMOS_WRITE, and a
318 # global rtc_lock ... it's not yet just another platform_device.
321 tristate "PC-style 'CMOS'"
322 depends on X86 || ALPHA || ARM || M32R || ATARI || PPC || MIPS
325 Say "yes" here to get direct support for the real time clock
326 found in every PC or ACPI-based system, and some other boards.
327 Specifically the original MC146818, compatibles like those in
328 PC south bridges, the DS12887 or M48T86, some multifunction
329 or LPC bus chips, and so on.
331 Your system will need to define the platform device used by
332 this driver, otherwise it won't be accessible. This means
333 you can safely enable this driver if you don't know whether
334 or not your board has this kind of hardware.
336 This driver can also be built as a module. If so, the module
337 will be called rtc-cmos.
339 config RTC_DRV_DS1216
340 tristate "Dallas DS1216"
343 If you say yes here you get support for the Dallas DS1216 RTC chips.
345 config RTC_DRV_DS1302
346 tristate "Dallas DS1302"
347 depends on SH_SECUREEDGE5410
349 If you say yes here you get support for the Dallas DS1302 RTC chips.
351 config RTC_DRV_DS1511
352 tristate "Dallas DS1511"
355 If you say yes here you get support for the
356 Dallas DS1511 timekeeping/watchdog chip.
358 This driver can also be built as a module. If so, the module
359 will be called rtc-ds1511.
361 config RTC_DRV_DS1553
362 tristate "Maxim/Dallas DS1553"
364 If you say yes here you get support for the
365 Maxim/Dallas DS1553 timekeeping chip.
367 This driver can also be built as a module. If so, the module
368 will be called rtc-ds1553.
370 config RTC_DRV_DS1742
371 tristate "Maxim/Dallas DS1742/1743"
373 If you say yes here you get support for the
374 Maxim/Dallas DS1742/1743 timekeeping chip.
376 This driver can also be built as a module. If so, the module
377 will be called rtc-ds1742.
379 config RTC_DRV_STK17TA8
380 tristate "Simtek STK17TA8"
383 If you say yes here you get support for the
384 Simtek STK17TA8 timekeeping chip.
386 This driver can also be built as a module. If so, the module
387 will be called rtc-stk17ta8.
389 config RTC_DRV_M48T86
390 tristate "ST M48T86/Dallas DS12887"
392 If you say Y here you will get support for the
393 ST M48T86 and Dallas DS12887 RTC chips.
395 This driver can also be built as a module. If so, the module
396 will be called rtc-m48t86.
398 config RTC_DRV_M48T59
401 If you say Y here you will get support for the
404 This driver can also be built as a module, if so, the module
405 will be called "rtc-m48t59".
408 tristate "EM Microelectronic V3020"
410 If you say yes here you will get support for the
411 EM Microelectronic v3020 RTC chip.
413 This driver can also be built as a module. If so, the module
414 will be called rtc-v3020.
416 comment "on-CPU RTC drivers"
420 depends on ARCH_OMAP15XX || ARCH_OMAP16XX || ARCH_OMAP730
422 Say "yes" here to support the real time clock on TI OMAP1 chips.
423 This driver can also be built as a module called rtc-omap.
426 tristate "Samsung S3C series SoC RTC"
427 depends on ARCH_S3C2410
429 RTC (Realtime Clock) driver for the clock inbuilt into the
430 Samsung S3C24XX series of SoCs. This can provide periodic
431 interrupt rates from 1Hz to 64Hz for user programs, and
434 The driver currently supports the common features on all the
435 S3C24XX range, such as the S3C2410, S3C2412, S3C2413, S3C2440
438 This driver can also be build as a module. If so, the module
439 will be called rtc-s3c.
441 config RTC_DRV_EP93XX
442 tristate "Cirrus Logic EP93XX"
443 depends on ARCH_EP93XX
445 If you say yes here you get support for the
446 RTC embedded in the Cirrus Logic EP93XX processors.
448 This driver can also be built as a module. If so, the module
449 will be called rtc-ep93xx.
451 config RTC_DRV_SA1100
452 tristate "SA11x0/PXA2xx"
453 depends on ARCH_SA1100 || ARCH_PXA
455 If you say Y here you will get access to the real time clock
456 built into your SA11x0 or PXA2xx CPU.
458 To compile this driver as a module, choose M here: the
459 module will be called rtc-sa1100.
462 tristate "SuperH On-Chip RTC"
463 depends on RTC_CLASS && SUPERH
465 Say Y here to enable support for the on-chip RTC found in
466 most SuperH processors.
468 To compile this driver as a module, choose M here: the
469 module will be called rtc-sh.
471 config RTC_DRV_VR41XX
472 tristate "NEC VR41XX"
473 depends on CPU_VR41XX
475 If you say Y here you will get access to the real time clock
476 built into your NEC VR41XX CPU.
478 To compile this driver as a module, choose M here: the
479 module will be called rtc-vr41xx.
482 tristate "ARM AMBA PL030 RTC"
485 If you say Y here you will get access to ARM AMBA
486 PrimeCell PL030 RTC found on certain ARM SOCs.
488 To compile this driver as a module, choose M here: the
489 module will be called rtc-pl030.
492 tristate "ARM AMBA PL031 RTC"
495 If you say Y here you will get access to ARM AMBA
496 PrimeCell PL031 RTC found on certain ARM SOCs.
498 To compile this driver as a module, choose M here: the
499 module will be called rtc-pl031.
501 config RTC_DRV_AT32AP700X
502 tristate "AT32AP700X series RTC"
503 depends on PLATFORM_AT32AP
505 Driver for the internal RTC (Realtime Clock) on Atmel AVR32
506 AT32AP700x family processors.
508 config RTC_DRV_AT91RM9200
509 tristate "AT91RM9200 or AT91SAM9RL"
510 depends on ARCH_AT91RM9200 || ARCH_AT91SAM9RL
512 Driver for the internal RTC (Realtime Clock) module found on
513 Atmel AT91RM9200's and AT91SAM9RL chips. On SAM9RL chips
514 this is powered by the backup power supply.
516 config RTC_DRV_AT91SAM9
517 tristate "AT91SAM9x/AT91CAP9"
518 depends on ARCH_AT91 && !(ARCH_AT91RM9200 || ARCH_AT91X40)
520 RTC driver for the Atmel AT91SAM9x and AT91CAP9 internal RTT
521 (Real Time Timer). These timers are powered by the backup power
522 supply (such as a small coin cell battery), but do not need to
525 (On AT91SAM9rl chips you probably want to use the dedicated RTC
526 module and leave the RTT available for other uses.)
528 config RTC_DRV_AT91SAM9_RTT
532 prompt "RTT module Number" if ARCH_AT91SAM9263
533 depends on RTC_DRV_AT91SAM9
535 More than one RTT module is available. You can choose which
536 one will be used as an RTC. The default of zero is normally
537 OK to use, though some systems use that for non-RTC purposes.
539 config RTC_DRV_AT91SAM9_GPBR
541 range 0 3 if !ARCH_AT91SAM9263
542 range 0 15 if ARCH_AT91SAM9263
544 prompt "Backup Register Number"
545 depends on RTC_DRV_AT91SAM9
547 The RTC driver needs to use one of the General Purpose Backup
548 Registers (GPBRs) as well as the RTT. You can choose which one
549 will be used. The default of zero is normally OK to use, but
550 on some systems other software needs to use that register.
553 tristate "Blackfin On-Chip RTC"
556 If you say yes here you will get support for the
557 Blackfin On-Chip Real Time Clock.
559 This driver can also be built as a module. If so, the module
560 will be called rtc-bfin.
562 config RTC_DRV_RS5C313
563 tristate "Ricoh RS5C313"
564 depends on SH_LANDISK
566 If you say yes here you get support for the Ricoh RS5C313 RTC chips.
569 tristate "PowerPC machine dependent RTC support"
572 The PowerPC kernel has machine-specific functions for accessing
573 the RTC. This exposes that functionality through the generic RTC