2 # RTC class/drivers configuration
12 depends on EXPERIMENTAL
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"
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.
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.
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 underlaying rtc chip
102 driver does not expose RTC_UIE ioctls. Those requests generate
103 once-per-second update interrupts, used for synchronization.
105 comment "RTC drivers"
108 # this 'CMOS' RTC driver is arch dependent because <asm-generic/rtc.h>
109 # requires <asm/mc146818rtc.h> defining CMOS_READ/CMOS_WRITE, and a
110 # global rtc_lock ... it's not yet just another platform_device.
113 tristate "PC-style 'CMOS' real time clock"
114 depends on RTC_CLASS && (X86 || ALPHA || ARM26 || ARM \
115 || M32R || ATARI || POWERPC)
117 Say "yes" here to get direct support for the real time clock
118 found in every PC or ACPI-based system, and some other boards.
119 Specifically the original MC146818, compatibles like those in
120 PC south bridges, the DS12887 or M48T86, some multifunction
121 or LPC bus chips, and so on.
123 Your system will need to define the platform device used by
124 this driver, otherwise it won't be accessible. This means
125 you can safely enable this driver if you don't know whether
126 or not your board has this kind of hardware.
128 This driver can also be built as a module. If so, the module
129 will be called rtc-cmos.
132 tristate "Xicor/Intersil X1205"
133 depends on RTC_CLASS && I2C
135 If you say yes here you get support for the
136 Xicor/Intersil X1205 RTC chip.
138 This driver can also be built as a module. If so, the module
139 will be called rtc-x1205.
141 config RTC_DRV_DS1307
142 tristate "Dallas/Maxim DS1307 and similar I2C RTC chips"
143 depends on RTC_CLASS && I2C
145 If you say yes here you get support for various compatible RTC
146 chips (often with battery backup) connected with I2C. This driver
147 should handle DS1307, DS1337, DS1338, DS1339, DS1340, ST M41T00,
148 and probably other chips. In some cases the RTC must already
149 have been initialized (by manufacturing or a bootloader).
151 The first seven registers on these chips hold an RTC, and other
152 registers may add features such as NVRAM, a trickle charger for
153 the RTC/NVRAM backup power, and alarms. This driver may not
154 expose all those available chip features.
156 This driver can also be built as a module. If so, the module
157 will be called rtc-ds1307.
159 config RTC_DRV_DS1553
160 tristate "Dallas DS1553"
163 If you say yes here you get support for the
164 Dallas DS1553 timekeeping chip.
166 This driver can also be built as a module. If so, the module
167 will be called rtc-ds1553.
169 config RTC_DRV_ISL1208
170 tristate "Intersil 1208"
171 depends on RTC_CLASS && I2C
173 If you say yes here you get support for the
174 Intersil 1208 RTC chip.
176 This driver can also be built as a module. If so, the module
177 will be called rtc-isl1208.
179 config RTC_DRV_DS1672
180 tristate "Dallas/Maxim DS1672"
181 depends on RTC_CLASS && I2C
183 If you say yes here you get support for the
184 Dallas/Maxim DS1672 timekeeping chip.
186 This driver can also be built as a module. If so, the module
187 will be called rtc-ds1672.
189 config RTC_DRV_DS1742
190 tristate "Dallas DS1742/1743"
193 If you say yes here you get support for the
194 Dallas DS1742/1743 timekeeping chip.
196 This driver can also be built as a module. If so, the module
197 will be called rtc-ds1742.
201 depends on RTC_CLASS && ( \
202 ARCH_OMAP15XX || ARCH_OMAP16XX || ARCH_OMAP730 )
204 Say "yes" here to support the real time clock on TI OMAP1 chips.
205 This driver can also be built as a module called rtc-omap.
207 config RTC_DRV_PCF8563
208 tristate "Philips PCF8563/Epson RTC8564"
209 depends on RTC_CLASS && I2C
211 If you say yes here you get support for the
212 Philips PCF8563 RTC chip. The Epson RTC8564
215 This driver can also be built as a module. If so, the module
216 will be called rtc-pcf8563.
218 config RTC_DRV_PCF8583
219 tristate "Philips PCF8583"
220 depends on RTC_CLASS && I2C && ARCH_RPC
222 If you say yes here you get support for the Philips PCF8583
223 RTC chip found on Acorn RiscPCs. This driver supports the
224 platform specific method of retrieving the current year from
227 This driver can also be built as a module. If so, the module
228 will be called rtc-pcf8583.
230 config RTC_DRV_RS5C348
231 tristate "Ricoh RS5C348A/B"
232 depends on RTC_CLASS && SPI
234 If you say yes here you get support for the
235 Ricoh RS5C348A and RS5C348B RTC chips.
237 This driver can also be built as a module. If so, the module
238 will be called rtc-rs5c348.
240 config RTC_DRV_RS5C372
241 tristate "Ricoh RS5C372A/B"
242 depends on RTC_CLASS && I2C
244 If you say yes here you get support for the
245 Ricoh RS5C372A and RS5C372B RTC chips.
247 This driver can also be built as a module. If so, the module
248 will be called rtc-rs5c372.
251 tristate "Samsung S3C series SoC RTC"
252 depends on RTC_CLASS && ARCH_S3C2410
254 RTC (Realtime Clock) driver for the clock inbuilt into the
255 Samsung S3C24XX series of SoCs. This can provide periodic
256 interrupt rates from 1Hz to 64Hz for user programs, and
259 The driver currently supports the common features on all the
260 S3C24XX range, such as the S3C2410, S3C2412, S3C2413, S3C2440
263 This driver can also be build as a module. If so, the module
264 will be called rtc-s3c.
266 config RTC_DRV_M48T86
267 tristate "ST M48T86/Dallas DS12887"
270 If you say Y here you will get support for the
271 ST M48T86 and Dallas DS12887 RTC chips.
273 This driver can also be built as a module. If so, the module
274 will be called rtc-m48t86.
276 config RTC_DRV_EP93XX
277 tristate "Cirrus Logic EP93XX"
278 depends on RTC_CLASS && ARCH_EP93XX
280 If you say yes here you get support for the
281 RTC embedded in the Cirrus Logic EP93XX processors.
283 This driver can also be built as a module. If so, the module
284 will be called rtc-ep93xx.
286 config RTC_DRV_SA1100
287 tristate "SA11x0/PXA2xx"
288 depends on RTC_CLASS && (ARCH_SA1100 || ARCH_PXA)
290 If you say Y here you will get access to the real time clock
291 built into your SA11x0 or PXA2xx CPU.
293 To compile this driver as a module, choose M here: the
294 module will be called rtc-sa1100.
297 tristate "SuperH On-Chip RTC"
298 depends on RTC_CLASS && SUPERH
300 Say Y here to enable support for the on-chip RTC found in
301 most SuperH processors.
303 To compile this driver as a module, choose M here: the
304 module will be called rtc-sh.
306 config RTC_DRV_VR41XX
307 tristate "NEC VR41XX"
308 depends on RTC_CLASS && CPU_VR41XX
310 If you say Y here you will get access to the real time clock
311 built into your NEC VR41XX CPU.
313 To compile this driver as a module, choose M here: the
314 module will be called rtc-vr41xx.
317 tristate "ARM AMBA PL031 RTC"
318 depends on RTC_CLASS && ARM_AMBA
320 If you say Y here you will get access to ARM AMBA
321 PrimeCell PL031 UART found on certain ARM SOCs.
323 To compile this driver as a module, choose M here: the
324 module will be called rtc-pl031.
326 config RTC_DRV_AT91RM9200
327 tristate "AT91RM9200"
328 depends on RTC_CLASS && ARCH_AT91RM9200
330 Driver for the Atmel AT91RM9200's internal RTC (Realtime Clock).
333 tristate "Test driver/device"
336 If you say yes here you get support for the
337 RTC test driver. It's a software RTC which can be
338 used to test the RTC subsystem APIs. It gets
339 the time from the system clock.
340 You want this driver only if you are doing development
341 on the RTC subsystem. Please read the source code
344 This driver can also be built as a module. If so, the module
345 will be called rtc-test.
347 config RTC_DRV_MAX6900
348 tristate "Maxim 6900"
349 depends on RTC_CLASS && I2C
351 If you say yes here you will get support for the
352 Maxim MAX6900 I2C RTC chip.
354 This driver can also be built as a module. If so, the module
355 will be called rtc-max6900.
357 config RTC_DRV_MAX6902
358 tristate "Maxim 6902"
359 depends on RTC_CLASS && SPI
361 If you say yes here you will get support for the
362 Maxim MAX6902 spi RTC chip.
364 This driver can also be built as a module. If so, the module
365 will be called rtc-max6902.
368 tristate "EM Microelectronic V3020"
371 If you say yes here you will get support for the
372 EM Microelectronic v3020 RTC chip.
374 This driver can also be built as a module. If so, the module
375 will be called rtc-v3020.
378 tristate "Blackfin On-Chip RTC"
379 depends on RTC_CLASS && BFIN
381 If you say yes here you will get support for the
382 Blackfin On-Chip Real Time Clock.
384 This driver can also be built as a module. If so, the module
385 will be called rtc-bfin.
387 config RTC_DRV_RS5C313
388 tristate "Ricoh RS5C313"
389 depends on RTC_CLASS && BROKEN
391 If you say yes here you get support for the Ricoh RS5C313 RTC chips.