2 # RTC class/drivers configuration
16 Generic RTC class support. If you say yes here, you will
17 be allowed to plug one or more RTCs to your system. You will
18 probably want to enable one or more of the interfaces below.
20 This driver can also be built as a module. If so, the module
21 will be called rtc-class.
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.
41 This clock should be battery-backed, so that it reads the correct
42 time when the system boots from a power-off state. Otherwise, your
43 system will need an external clock source (like an NTP server).
45 If the clock you specify here is not battery backed, it may still
46 be useful to reinitialize system time when resuming from system
47 sleep states. Do not specify an RTC here unless it stays powered
48 during all this system's supported sleep states.
51 bool "RTC debug support"
52 depends on RTC_CLASS = y
54 Say yes here to enable debugging support in the RTC framework
55 and individual RTC drivers.
57 comment "RTC interfaces"
61 boolean "/sys/class/rtc/rtcN (sysfs)"
62 depends on RTC_CLASS && SYSFS
65 Say yes here if you want to use your RTCs using sysfs interfaces,
66 /sys/class/rtc/rtc0 through /sys/.../rtcN.
68 This driver can also be built as a module. If so, the module
69 will be called rtc-sysfs.
72 boolean "/proc/driver/rtc (procfs for rtc0)"
73 depends on RTC_CLASS && PROC_FS
76 Say yes here if you want to use your first RTC through the proc
77 interface, /proc/driver/rtc. Other RTCs will not be available
80 This driver can also be built as a module. If so, the module
81 will be called rtc-proc.
84 boolean "/dev/rtcN (character devices)"
88 Say yes here if you want to use your RTCs using the /dev
89 interfaces, which "udev" sets up as /dev/rtc0 through
90 /dev/rtcN. You may want to set up a symbolic link so one
91 of these can be accessed as /dev/rtc, which is a name
92 expected by "hwclock" and some other programs.
94 This driver can also be built as a module. If so, the module
95 will be called rtc-dev.
97 config RTC_INTF_DEV_UIE_EMUL
98 bool "RTC UIE emulation on dev interface"
99 depends on RTC_INTF_DEV
101 Provides an emulation for RTC_UIE if the underlying rtc chip
102 driver does not expose RTC_UIE ioctls. Those requests generate
103 once-per-second update interrupts, used for synchronization.
106 tristate "Test driver/device"
109 If you say yes here you get support for the
110 RTC test driver. It's a software RTC which can be
111 used to test the RTC subsystem APIs. It gets
112 the time from the system clock.
113 You want this driver only if you are doing development
114 on the RTC subsystem. Please read the source code
117 This driver can also be built as a module. If so, the module
118 will be called rtc-test.
120 comment "I2C RTC drivers"
121 depends on RTC_CLASS && I2C
123 config RTC_DRV_DS1307
124 tristate "Dallas/Maxim DS1307/37/38/39/40, ST M41T00"
125 depends on RTC_CLASS && I2C
127 If you say yes here you get support for various compatible RTC
128 chips (often with battery backup) connected with I2C. This driver
129 should handle DS1307, DS1337, DS1338, DS1339, DS1340, ST M41T00,
130 and probably other chips. In some cases the RTC must already
131 have been initialized (by manufacturing or a bootloader).
133 The first seven registers on these chips hold an RTC, and other
134 registers may add features such as NVRAM, a trickle charger for
135 the RTC/NVRAM backup power, and alarms. This driver may not
136 expose all those available chip features.
138 This driver can also be built as a module. If so, the module
139 will be called rtc-ds1307.
141 config RTC_DRV_DS1672
142 tristate "Dallas/Maxim DS1672"
143 depends on RTC_CLASS && I2C
145 If you say yes here you get support for the
146 Dallas/Maxim DS1672 timekeeping chip.
148 This driver can also be built as a module. If so, the module
149 will be called rtc-ds1672.
151 config RTC_DRV_MAX6900
152 tristate "Maxim 6900"
153 depends on RTC_CLASS && I2C
155 If you say yes here you will get support for the
156 Maxim MAX6900 I2C RTC chip.
158 This driver can also be built as a module. If so, the module
159 will be called rtc-max6900.
161 config RTC_DRV_RS5C372
162 tristate "Ricoh RS5C372A/B, RV5C386, RV5C387A"
163 depends on RTC_CLASS && I2C
165 If you say yes here you get support for the
166 Ricoh RS5C372A, RS5C372B, RV5C386, and RV5C387A RTC chips.
168 This driver can also be built as a module. If so, the module
169 will be called rtc-rs5c372.
171 config RTC_DRV_ISL1208
172 tristate "Intersil 1208"
173 depends on RTC_CLASS && I2C
175 If you say yes here you get support for the
176 Intersil 1208 RTC chip.
178 This driver can also be built as a module. If so, the module
179 will be called rtc-isl1208.
182 tristate "Xicor/Intersil X1205"
183 depends on RTC_CLASS && I2C
185 If you say yes here you get support for the
186 Xicor/Intersil X1205 RTC chip.
188 This driver can also be built as a module. If so, the module
189 will be called rtc-x1205.
191 config RTC_DRV_PCF8563
192 tristate "Philips PCF8563/Epson RTC8564"
193 depends on RTC_CLASS && I2C
195 If you say yes here you get support for the
196 Philips PCF8563 RTC chip. The Epson RTC8564
199 This driver can also be built as a module. If so, the module
200 will be called rtc-pcf8563.
202 config RTC_DRV_PCF8583
203 tristate "Philips PCF8583"
204 depends on RTC_CLASS && I2C
206 If you say yes here you get support for the Philips PCF8583
207 RTC chip found on Acorn RiscPCs. This driver supports the
208 platform specific method of retrieving the current year from
209 the RTC's SRAM. It will work on other platforms with the same
210 chip, but the year will probably have to be tweaked.
212 This driver can also be built as a module. If so, the module
213 will be called rtc-pcf8583.
215 comment "SPI RTC drivers"
216 depends on RTC_CLASS && SPI_MASTER
218 config RTC_DRV_RS5C348
219 tristate "Ricoh RS5C348A/B"
220 depends on RTC_CLASS && SPI_MASTER
222 If you say yes here you get support for the
223 Ricoh RS5C348A and RS5C348B RTC chips.
225 This driver can also be built as a module. If so, the module
226 will be called rtc-rs5c348.
228 config RTC_DRV_MAX6902
229 tristate "Maxim 6902"
230 depends on RTC_CLASS && SPI_MASTER
232 If you say yes here you will get support for the
233 Maxim MAX6902 SPI RTC chip.
235 This driver can also be built as a module. If so, the module
236 will be called rtc-max6902.
238 comment "Platform RTC drivers"
241 # this 'CMOS' RTC driver is arch dependent because <asm-generic/rtc.h>
242 # requires <asm/mc146818rtc.h> defining CMOS_READ/CMOS_WRITE, and a
243 # global rtc_lock ... it's not yet just another platform_device.
246 tristate "PC-style 'CMOS'"
247 depends on RTC_CLASS && (X86 || ALPHA || ARM26 || ARM \
248 || M32R || ATARI || PPC || MIPS)
250 Say "yes" here to get direct support for the real time clock
251 found in every PC or ACPI-based system, and some other boards.
252 Specifically the original MC146818, compatibles like those in
253 PC south bridges, the DS12887 or M48T86, some multifunction
254 or LPC bus chips, and so on.
256 Your system will need to define the platform device used by
257 this driver, otherwise it won't be accessible. This means
258 you can safely enable this driver if you don't know whether
259 or not your board has this kind of hardware.
261 This driver can also be built as a module. If so, the module
262 will be called rtc-cmos.
264 config RTC_DRV_DS1553
265 tristate "Dallas DS1553"
268 If you say yes here you get support for the
269 Dallas DS1553 timekeeping chip.
271 This driver can also be built as a module. If so, the module
272 will be called rtc-ds1553.
274 config RTC_DRV_DS1742
275 tristate "Dallas DS1742/1743"
278 If you say yes here you get support for the
279 Dallas DS1742/1743 timekeeping chip.
281 This driver can also be built as a module. If so, the module
282 will be called rtc-ds1742.
284 config RTC_DRV_M48T86
285 tristate "ST M48T86/Dallas DS12887"
288 If you say Y here you will get support for the
289 ST M48T86 and Dallas DS12887 RTC chips.
291 This driver can also be built as a module. If so, the module
292 will be called rtc-m48t86.
295 tristate "EM Microelectronic V3020"
298 If you say yes here you will get support for the
299 EM Microelectronic v3020 RTC chip.
301 This driver can also be built as a module. If so, the module
302 will be called rtc-v3020.
304 comment "on-CPU RTC drivers"
309 depends on RTC_CLASS && ( \
310 ARCH_OMAP15XX || ARCH_OMAP16XX || ARCH_OMAP730 )
312 Say "yes" here to support the real time clock on TI OMAP1 chips.
313 This driver can also be built as a module called rtc-omap.
316 tristate "Samsung S3C series SoC RTC"
317 depends on RTC_CLASS && ARCH_S3C2410
319 RTC (Realtime Clock) driver for the clock inbuilt into the
320 Samsung S3C24XX series of SoCs. This can provide periodic
321 interrupt rates from 1Hz to 64Hz for user programs, and
324 The driver currently supports the common features on all the
325 S3C24XX range, such as the S3C2410, S3C2412, S3C2413, S3C2440
328 This driver can also be build as a module. If so, the module
329 will be called rtc-s3c.
331 config RTC_DRV_EP93XX
332 tristate "Cirrus Logic EP93XX"
333 depends on RTC_CLASS && ARCH_EP93XX
335 If you say yes here you get support for the
336 RTC embedded in the Cirrus Logic EP93XX processors.
338 This driver can also be built as a module. If so, the module
339 will be called rtc-ep93xx.
341 config RTC_DRV_SA1100
342 tristate "SA11x0/PXA2xx"
343 depends on RTC_CLASS && (ARCH_SA1100 || ARCH_PXA)
345 If you say Y here you will get access to the real time clock
346 built into your SA11x0 or PXA2xx CPU.
348 To compile this driver as a module, choose M here: the
349 module will be called rtc-sa1100.
352 tristate "SuperH On-Chip RTC"
353 depends on RTC_CLASS && SUPERH
355 Say Y here to enable support for the on-chip RTC found in
356 most SuperH processors.
358 To compile this driver as a module, choose M here: the
359 module will be called rtc-sh.
361 config RTC_DRV_VR41XX
362 tristate "NEC VR41XX"
363 depends on RTC_CLASS && CPU_VR41XX
365 If you say Y here you will get access to the real time clock
366 built into your NEC VR41XX CPU.
368 To compile this driver as a module, choose M here: the
369 module will be called rtc-vr41xx.
372 tristate "ARM AMBA PL031 RTC"
373 depends on RTC_CLASS && ARM_AMBA
375 If you say Y here you will get access to ARM AMBA
376 PrimeCell PL031 RTC found on certain ARM SOCs.
378 To compile this driver as a module, choose M here: the
379 module will be called rtc-pl031.
381 config RTC_DRV_AT32AP700X
382 tristate "AT32AP700X series RTC"
383 depends on RTC_CLASS && PLATFORM_AT32AP
385 Driver for the internal RTC (Realtime Clock) on Atmel AVR32
386 AT32AP700x family processors.
388 config RTC_DRV_AT91RM9200
389 tristate "AT91RM9200"
390 depends on RTC_CLASS && ARCH_AT91RM9200
392 Driver for the Atmel AT91RM9200's internal RTC (Realtime Clock).
395 tristate "Blackfin On-Chip RTC"
396 depends on RTC_CLASS && BFIN
398 If you say yes here you will get support for the
399 Blackfin On-Chip Real Time Clock.
401 This driver can also be built as a module. If so, the module
402 will be called rtc-bfin.
404 config RTC_DRV_RS5C313
405 tristate "Ricoh RS5C313"
406 depends on RTC_CLASS && SH_LANDISK
408 If you say yes here you get support for the Ricoh RS5C313 RTC chips.