2 # RTC class/drivers configuration
13 depends on EXPERIMENTAL
17 Generic RTC class support. If you say yes here, you will
18 be allowed to plug one or more RTCs to your system. You will
19 probably want to enable one or more of the interfaces below.
21 This driver can also be built as a module. If so, the module
22 will be called rtc-class.
25 bool "Set system time from RTC on startup and resume"
26 depends on RTC_CLASS = y
29 If you say yes here, the system time (wall clock) will be set using
30 the value read from a specified RTC device. This is useful to avoid
31 unnecessary fsck runs at boot time, and to network better.
33 config RTC_HCTOSYS_DEVICE
34 string "RTC used to set the system time"
35 depends on RTC_HCTOSYS = y
38 The RTC device that will be used to (re)initialize the system
39 clock, usually rtc0. Initialization is done when the system
40 starts up, and when it resumes from a low power state.
42 This clock should be battery-backed, so that it reads the correct
43 time when the system boots from a power-off state. Otherwise, your
44 system will need an external clock source (like an NTP server).
46 If the clock you specify here is not battery backed, it may still
47 be useful to reinitialize system time when resuming from system
48 sleep states. Do not specify an RTC here unless it stays powered
49 during all this system's supported sleep states.
52 bool "RTC debug support"
53 depends on RTC_CLASS = y
55 Say yes here to enable debugging support in the RTC framework
56 and individual RTC drivers.
58 comment "RTC interfaces"
63 depends on RTC_CLASS && SYSFS
66 Say yes here if you want to use your RTCs using sysfs interfaces,
67 /sys/class/rtc/rtc0 through /sys/.../rtcN.
69 This driver can also be built as a module. If so, the module
70 will be called rtc-sysfs.
74 depends on RTC_CLASS && PROC_FS
77 Say yes here if you want to use your first RTC through the proc
78 interface, /proc/driver/rtc. Other RTCs will not be available
81 This driver can also be built as a module. If so, the module
82 will be called rtc-proc.
89 Say yes here if you want to use your RTCs using the /dev
90 interfaces, which "udev" sets up as /dev/rtc0 through
91 /dev/rtcN. You may want to set up a symbolic link so one
92 of these can be accessed as /dev/rtc, which is a name
93 expected by "hwclock" and some other programs.
95 This driver can also be built as a module. If so, the module
96 will be called rtc-dev.
98 config RTC_INTF_DEV_UIE_EMUL
99 bool "RTC UIE emulation on dev interface"
100 depends on RTC_INTF_DEV
102 Provides an emulation for RTC_UIE if the underlying rtc chip
103 driver does not expose RTC_UIE ioctls. Those requests generate
104 once-per-second update interrupts, used for synchronization.
107 tristate "Test driver/device"
110 If you say yes here you get support for the
111 RTC test driver. It's a software RTC which can be
112 used to test the RTC subsystem APIs. It gets
113 the time from the system clock.
114 You want this driver only if you are doing development
115 on the RTC subsystem. Please read the source code
118 This driver can also be built as a module. If so, the module
119 will be called rtc-test.
121 comment "I2C RTC drivers"
124 config RTC_DRV_DS1307
125 tristate "Dallas/Maxim DS1307/37/38/39/40, ST M41T00"
126 depends on RTC_CLASS && I2C
128 If you say yes here you get support for various compatible RTC
129 chips (often with battery backup) connected with I2C. This driver
130 should handle DS1307, DS1337, DS1338, DS1339, DS1340, ST M41T00,
131 and probably other chips. In some cases the RTC must already
132 have been initialized (by manufacturing or a bootloader).
134 The first seven registers on these chips hold an RTC, and other
135 registers may add features such as NVRAM, a trickle charger for
136 the RTC/NVRAM backup power, and alarms. This driver may not
137 expose all those available chip features.
139 This driver can also be built as a module. If so, the module
140 will be called rtc-ds1307.
142 config RTC_DRV_DS1672
143 tristate "Dallas/Maxim DS1672"
144 depends on RTC_CLASS && I2C
146 If you say yes here you get support for the
147 Dallas/Maxim DS1672 timekeeping chip.
149 This driver can also be built as a module. If so, the module
150 will be called rtc-ds1672.
152 config RTC_DRV_MAX6900
153 tristate "Maxim 6900"
154 depends on RTC_CLASS && I2C
156 If you say yes here you will get support for the
157 Maxim MAX6900 I2C RTC chip.
159 This driver can also be built as a module. If so, the module
160 will be called rtc-max6900.
162 config RTC_DRV_RS5C372
163 tristate "Ricoh RS5C372A/B"
164 depends on RTC_CLASS && I2C
166 If you say yes here you get support for the
167 Ricoh RS5C372A and RS5C372B RTC chips.
169 This driver can also be built as a module. If so, the module
170 will be called rtc-rs5c372.
172 config RTC_DRV_ISL1208
173 tristate "Intersil 1208"
174 depends on RTC_CLASS && I2C
176 If you say yes here you get support for the
177 Intersil 1208 RTC chip.
179 This driver can also be built as a module. If so, the module
180 will be called rtc-isl1208.
183 tristate "Xicor/Intersil X1205"
184 depends on RTC_CLASS && I2C
186 If you say yes here you get support for the
187 Xicor/Intersil X1205 RTC chip.
189 This driver can also be built as a module. If so, the module
190 will be called rtc-x1205.
192 config RTC_DRV_PCF8563
193 tristate "Philips PCF8563/Epson RTC8564"
194 depends on RTC_CLASS && I2C
196 If you say yes here you get support for the
197 Philips PCF8563 RTC chip. The Epson RTC8564
200 This driver can also be built as a module. If so, the module
201 will be called rtc-pcf8563.
203 config RTC_DRV_PCF8583
204 tristate "Philips PCF8583"
205 depends on RTC_CLASS && I2C
207 If you say yes here you get support for the Philips PCF8583
208 RTC chip found on Acorn RiscPCs. This driver supports the
209 platform specific method of retrieving the current year from
210 the RTC's SRAM. It will work on other platforms with the same
211 chip, but the year will probably have to be tweaked.
213 This driver can also be built as a module. If so, the module
214 will be called rtc-pcf8583.
216 comment "SPI RTC drivers"
219 config RTC_DRV_RS5C348
220 tristate "Ricoh RS5C348A/B"
221 depends on RTC_CLASS && SPI
223 If you say yes here you get support for the
224 Ricoh RS5C348A and RS5C348B RTC chips.
226 This driver can also be built as a module. If so, the module
227 will be called rtc-rs5c348.
229 config RTC_DRV_MAX6902
230 tristate "Maxim 6902"
231 depends on RTC_CLASS && SPI
233 If you say yes here you will get support for the
234 Maxim MAX6902 SPI RTC chip.
236 This driver can also be built as a module. If so, the module
237 will be called rtc-max6902.
239 comment "Platform RTC drivers"
242 # this 'CMOS' RTC driver is arch dependent because <asm-generic/rtc.h>
243 # requires <asm/mc146818rtc.h> defining CMOS_READ/CMOS_WRITE, and a
244 # global rtc_lock ... it's not yet just another platform_device.
247 tristate "PC-style 'CMOS'"
248 depends on RTC_CLASS && (X86 || ALPHA || ARM26 || ARM \
249 || M32R || ATARI || POWERPC)
251 Say "yes" here to get direct support for the real time clock
252 found in every PC or ACPI-based system, and some other boards.
253 Specifically the original MC146818, compatibles like those in
254 PC south bridges, the DS12887 or M48T86, some multifunction
255 or LPC bus chips, and so on.
257 Your system will need to define the platform device used by
258 this driver, otherwise it won't be accessible. This means
259 you can safely enable this driver if you don't know whether
260 or not your board has this kind of hardware.
262 This driver can also be built as a module. If so, the module
263 will be called rtc-cmos.
265 config RTC_DRV_DS1553
266 tristate "Dallas DS1553"
269 If you say yes here you get support for the
270 Dallas DS1553 timekeeping chip.
272 This driver can also be built as a module. If so, the module
273 will be called rtc-ds1553.
275 config RTC_DRV_DS1742
276 tristate "Dallas DS1742/1743"
279 If you say yes here you get support for the
280 Dallas DS1742/1743 timekeeping chip.
282 This driver can also be built as a module. If so, the module
283 will be called rtc-ds1742.
285 config RTC_DRV_M48T86
286 tristate "ST M48T86/Dallas DS12887"
289 If you say Y here you will get support for the
290 ST M48T86 and Dallas DS12887 RTC chips.
292 This driver can also be built as a module. If so, the module
293 will be called rtc-m48t86.
296 tristate "EM Microelectronic V3020"
299 If you say yes here you will get support for the
300 EM Microelectronic v3020 RTC chip.
302 This driver can also be built as a module. If so, the module
303 will be called rtc-v3020.
305 comment "on-CPU RTC drivers"
310 depends on RTC_CLASS && ( \
311 ARCH_OMAP15XX || ARCH_OMAP16XX || ARCH_OMAP730 )
313 Say "yes" here to support the real time clock on TI OMAP1 chips.
314 This driver can also be built as a module called rtc-omap.
317 tristate "Samsung S3C series SoC RTC"
318 depends on RTC_CLASS && ARCH_S3C2410
320 RTC (Realtime Clock) driver for the clock inbuilt into the
321 Samsung S3C24XX series of SoCs. This can provide periodic
322 interrupt rates from 1Hz to 64Hz for user programs, and
325 The driver currently supports the common features on all the
326 S3C24XX range, such as the S3C2410, S3C2412, S3C2413, S3C2440
329 This driver can also be build as a module. If so, the module
330 will be called rtc-s3c.
332 config RTC_DRV_EP93XX
333 tristate "Cirrus Logic EP93XX"
334 depends on RTC_CLASS && ARCH_EP93XX
336 If you say yes here you get support for the
337 RTC embedded in the Cirrus Logic EP93XX processors.
339 This driver can also be built as a module. If so, the module
340 will be called rtc-ep93xx.
342 config RTC_DRV_SA1100
343 tristate "SA11x0/PXA2xx"
344 depends on RTC_CLASS && (ARCH_SA1100 || ARCH_PXA)
346 If you say Y here you will get access to the real time clock
347 built into your SA11x0 or PXA2xx CPU.
349 To compile this driver as a module, choose M here: the
350 module will be called rtc-sa1100.
353 tristate "SuperH On-Chip RTC"
354 depends on RTC_CLASS && SUPERH
356 Say Y here to enable support for the on-chip RTC found in
357 most SuperH processors.
359 To compile this driver as a module, choose M here: the
360 module will be called rtc-sh.
362 config RTC_DRV_VR41XX
363 tristate "NEC VR41XX"
364 depends on RTC_CLASS && CPU_VR41XX
366 If you say Y here you will get access to the real time clock
367 built into your NEC VR41XX CPU.
369 To compile this driver as a module, choose M here: the
370 module will be called rtc-vr41xx.
373 tristate "ARM AMBA PL031 RTC"
374 depends on RTC_CLASS && ARM_AMBA
376 If you say Y here you will get access to ARM AMBA
377 PrimeCell PL031 RTC found on certain ARM SOCs.
379 To compile this driver as a module, choose M here: the
380 module will be called rtc-pl031.
382 config RTC_DRV_AT91RM9200
383 tristate "AT91RM9200"
384 depends on RTC_CLASS && ARCH_AT91RM9200
386 Driver for the Atmel AT91RM9200's internal RTC (Realtime Clock).
389 tristate "Blackfin On-Chip RTC"
390 depends on RTC_CLASS && BFIN
392 If you say yes here you will get support for the
393 Blackfin On-Chip Real Time Clock.
395 This driver can also be built as a module. If so, the module
396 will be called rtc-bfin.
398 config RTC_DRV_RS5C313
399 tristate "Ricoh RS5C313"
400 depends on RTC_CLASS && BROKEN
402 If you say yes here you get support for the Ricoh RS5C313 RTC chips.