xref: /linux/drivers/rtc/Kconfig (revision ed3174d93c342b8b2eeba6bbd124707d55304a7b)
1#
2# RTC class/drivers configuration
3#
4
5config RTC_LIB
6	tristate
7
8menuconfig RTC_CLASS
9	tristate "Real Time Clock"
10	default n
11	depends on !S390
12	select RTC_LIB
13	help
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.
17
18	  This driver can also be built as a module. If so, the module
19	  will be called rtc-class.
20
21if RTC_CLASS
22
23if GEN_RTC || RTC
24comment "Conflicting RTC option has been selected, check GEN_RTC and RTC"
25endif
26
27config RTC_HCTOSYS
28	bool "Set system time from RTC on startup and resume"
29	depends on RTC_CLASS = y
30	default y
31	help
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.
35
36config RTC_HCTOSYS_DEVICE
37	string "RTC used to set the system time"
38	depends on RTC_HCTOSYS = y
39	default "rtc0"
40	help
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
45	  timezone correction.
46
47	  The driver for this RTC device must be loaded before late_initcall
48	  functions run, so it must usually be statically linked.
49
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).
53
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.
58
59config RTC_DEBUG
60	bool "RTC debug support"
61	depends on RTC_CLASS = y
62	help
63	  Say yes here to enable debugging support in the RTC framework
64	  and individual RTC drivers.
65
66comment "RTC interfaces"
67
68config RTC_INTF_SYSFS
69	boolean "/sys/class/rtc/rtcN (sysfs)"
70	depends on SYSFS
71	default RTC_CLASS
72	help
73	  Say yes here if you want to use your RTCs using sysfs interfaces,
74	  /sys/class/rtc/rtc0 through /sys/.../rtcN.
75
76	  This driver can also be built as a module. If so, the module
77	  will be called rtc-sysfs.
78
79config RTC_INTF_PROC
80	boolean "/proc/driver/rtc (procfs for rtc0)"
81	depends on PROC_FS
82	default RTC_CLASS
83	help
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
86	  through that API.
87
88	  This driver can also be built as a module. If so, the module
89	  will be called rtc-proc.
90
91config RTC_INTF_DEV
92	boolean "/dev/rtcN (character devices)"
93	default RTC_CLASS
94	help
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.
100
101	  This driver can also be built as a module. If so, the module
102	  will be called rtc-dev.
103
104config RTC_INTF_DEV_UIE_EMUL
105	bool "RTC UIE emulation on dev interface"
106	depends on RTC_INTF_DEV
107	help
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.
111
112config RTC_DRV_TEST
113	tristate "Test driver/device"
114	help
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
121	  for further details.
122
123	  This driver can also be built as a module. If so, the module
124	  will be called rtc-test.
125
126comment "I2C RTC drivers"
127	depends on I2C
128
129if I2C
130
131config RTC_DRV_DS1307
132	tristate "Dallas/Maxim DS1307/37/38/39/40, ST M41T00"
133	help
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).
139
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.
144
145	  This driver can also be built as a module. If so, the module
146	  will be called rtc-ds1307.
147
148config RTC_DRV_DS1374
149	tristate "Dallas/Maxim DS1374"
150	depends on RTC_CLASS && I2C
151	help
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.
155
156	  This driver can also be built as a module.  If so, the module
157	  will be called rtc-ds1374.
158
159config RTC_DRV_DS1672
160	tristate "Dallas/Maxim DS1672"
161	help
162	  If you say yes here you get support for the
163	  Dallas/Maxim DS1672 timekeeping chip.
164
165	  This driver can also be built as a module. If so, the module
166	  will be called rtc-ds1672.
167
168config RTC_DRV_MAX6900
169	tristate "Maxim MAX6900"
170	help
171	  If you say yes here you will get support for the
172	  Maxim MAX6900 I2C RTC chip.
173
174	  This driver can also be built as a module. If so, the module
175	  will be called rtc-max6900.
176
177config RTC_DRV_RS5C372
178	tristate "Ricoh RS5C372A/B, RV5C386, RV5C387A"
179	help
180	  If you say yes here you get support for the
181	  Ricoh RS5C372A, RS5C372B, RV5C386, and RV5C387A RTC chips.
182
183	  This driver can also be built as a module. If so, the module
184	  will be called rtc-rs5c372.
185
186config RTC_DRV_ISL1208
187	tristate "Intersil ISL1208"
188	help
189	  If you say yes here you get support for the
190	  Intersil ISL1208 RTC chip.
191
192	  This driver can also be built as a module. If so, the module
193	  will be called rtc-isl1208.
194
195config RTC_DRV_X1205
196	tristate "Xicor/Intersil X1205"
197	help
198	  If you say yes here you get support for the
199	  Xicor/Intersil X1205 RTC chip.
200
201	  This driver can also be built as a module. If so, the module
202	  will be called rtc-x1205.
203
204config RTC_DRV_PCF8563
205	tristate "Philips PCF8563/Epson RTC8564"
206	help
207	  If you say yes here you get support for the
208	  Philips PCF8563 RTC chip. The Epson RTC8564
209	  should work as well.
210
211	  This driver can also be built as a module. If so, the module
212	  will be called rtc-pcf8563.
213
214config RTC_DRV_PCF8583
215	tristate "Philips PCF8583"
216	help
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.
222
223	  This driver can also be built as a module. If so, the module
224	  will be called rtc-pcf8583.
225
226config RTC_DRV_M41T80
227	tristate "ST M41T80/81/82/83/84/85/87"
228	help
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
232	  and M41ST87.
233
234	  This driver can also be built as a module. If so, the module
235	  will be called rtc-m41t80.
236
237config RTC_DRV_M41T80_WDT
238	bool "ST M41T80 series RTC watchdog timer"
239	depends on RTC_DRV_M41T80
240	help
241	  If you say Y here you will get support for the
242	  watchdog timer in ST M41T80 RTC chips series.
243
244config RTC_DRV_TWL92330
245	boolean "TI TWL92330/Menelaus"
246	depends on MENELAUS
247	help
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.
252
253endif # I2C
254
255comment "SPI RTC drivers"
256
257if SPI_MASTER
258
259config RTC_DRV_MAX6902
260	tristate "Maxim MAX6902"
261	help
262	  If you say yes here you will get support for the
263	  Maxim MAX6902 SPI RTC chip.
264
265	  This driver can also be built as a module. If so, the module
266	  will be called rtc-max6902.
267
268config RTC_DRV_R9701
269	tristate "Epson RTC-9701JE"
270	help
271	  If you say yes here you will get support for the
272	  Epson RTC-9701JE SPI RTC chip.
273
274	  This driver can also be built as a module. If so, the module
275	  will be called rtc-r9701.
276
277config RTC_DRV_RS5C348
278	tristate "Ricoh RS5C348A/B"
279	help
280	  If you say yes here you get support for the
281	  Ricoh RS5C348A and RS5C348B RTC chips.
282
283	  This driver can also be built as a module. If so, the module
284	  will be called rtc-rs5c348.
285
286endif # SPI_MASTER
287
288comment "Platform RTC drivers"
289
290# this 'CMOS' RTC driver is arch dependent because <asm-generic/rtc.h>
291# requires <asm/mc146818rtc.h> defining CMOS_READ/CMOS_WRITE, and a
292# global rtc_lock ... it's not yet just another platform_device.
293
294config RTC_DRV_CMOS
295	tristate "PC-style 'CMOS'"
296	depends on X86 || ALPHA || ARM || M32R || ATARI || PPC || MIPS
297	help
298	  Say "yes" here to get direct support for the real time clock
299	  found in every PC or ACPI-based system, and some other boards.
300	  Specifically the original MC146818, compatibles like those in
301	  PC south bridges, the DS12887 or M48T86, some multifunction
302	  or LPC bus chips, and so on.
303
304	  Your system will need to define the platform device used by
305	  this driver, otherwise it won't be accessible.  This means
306	  you can safely enable this driver if you don't know whether
307	  or not your board has this kind of hardware.
308
309	  This driver can also be built as a module. If so, the module
310	  will be called rtc-cmos.
311
312config RTC_DRV_DS1216
313	tristate "Dallas DS1216"
314	depends on SNI_RM
315	help
316	  If you say yes here you get support for the Dallas DS1216 RTC chips.
317
318config RTC_DRV_DS1302
319	tristate "Dallas DS1302"
320	depends on SH_SECUREEDGE5410
321	help
322	  If you say yes here you get support for the Dallas DS1302 RTC chips.
323
324config RTC_DRV_DS1511
325	tristate "Dallas DS1511"
326	depends on RTC_CLASS
327	help
328	  If you say yes here you get support for the
329	  Dallas DS1511 timekeeping/watchdog chip.
330
331	  This driver can also be built as a module. If so, the module
332	  will be called rtc-ds1511.
333
334config RTC_DRV_DS1553
335	tristate "Maxim/Dallas DS1553"
336	help
337	  If you say yes here you get support for the
338	  Maxim/Dallas DS1553 timekeeping chip.
339
340	  This driver can also be built as a module. If so, the module
341	  will be called rtc-ds1553.
342
343config RTC_DRV_DS1742
344	tristate "Maxim/Dallas DS1742/1743"
345	help
346	  If you say yes here you get support for the
347	  Maxim/Dallas DS1742/1743 timekeeping chip.
348
349	  This driver can also be built as a module. If so, the module
350	  will be called rtc-ds1742.
351
352config RTC_DRV_STK17TA8
353	tristate "Simtek STK17TA8"
354	depends on RTC_CLASS
355	help
356	  If you say yes here you get support for the
357	  Simtek STK17TA8 timekeeping chip.
358
359	  This driver can also be built as a module. If so, the module
360	  will be called rtc-stk17ta8.
361
362config RTC_DRV_M48T86
363	tristate "ST M48T86/Dallas DS12887"
364	help
365	  If you say Y here you will get support for the
366	  ST M48T86 and Dallas DS12887 RTC chips.
367
368	  This driver can also be built as a module. If so, the module
369	  will be called rtc-m48t86.
370
371config RTC_DRV_M48T59
372	tristate "ST M48T59"
373	help
374	  If you say Y here you will get support for the
375	  ST M48T59 RTC chip.
376
377	  This driver can also be built as a module, if so, the module
378	  will be called "rtc-m48t59".
379
380config RTC_DRV_V3020
381	tristate "EM Microelectronic V3020"
382	help
383	  If you say yes here you will get support for the
384	  EM Microelectronic v3020 RTC chip.
385
386	  This driver can also be built as a module. If so, the module
387	  will be called rtc-v3020.
388
389comment "on-CPU RTC drivers"
390
391config RTC_DRV_OMAP
392	tristate "TI OMAP1"
393	depends on ARCH_OMAP15XX || ARCH_OMAP16XX || ARCH_OMAP730
394	help
395	  Say "yes" here to support the real time clock on TI OMAP1 chips.
396	  This driver can also be built as a module called rtc-omap.
397
398config RTC_DRV_S3C
399	tristate "Samsung S3C series SoC RTC"
400	depends on ARCH_S3C2410
401	help
402	  RTC (Realtime Clock) driver for the clock inbuilt into the
403	  Samsung S3C24XX series of SoCs. This can provide periodic
404	  interrupt rates from 1Hz to 64Hz for user programs, and
405	  wakeup from Alarm.
406
407	  The driver currently supports the common features on all the
408	  S3C24XX range, such as the S3C2410, S3C2412, S3C2413, S3C2440
409	  and S3C2442.
410
411	  This driver can also be build as a module. If so, the module
412	  will be called rtc-s3c.
413
414config RTC_DRV_EP93XX
415	tristate "Cirrus Logic EP93XX"
416	depends on ARCH_EP93XX
417	help
418	  If you say yes here you get support for the
419	  RTC embedded in the Cirrus Logic EP93XX processors.
420
421	  This driver can also be built as a module. If so, the module
422	  will be called rtc-ep93xx.
423
424config RTC_DRV_SA1100
425	tristate "SA11x0/PXA2xx"
426	depends on ARCH_SA1100 || ARCH_PXA
427	help
428	  If you say Y here you will get access to the real time clock
429	  built into your SA11x0 or PXA2xx CPU.
430
431	  To compile this driver as a module, choose M here: the
432	  module will be called rtc-sa1100.
433
434config RTC_DRV_SH
435	tristate "SuperH On-Chip RTC"
436	depends on RTC_CLASS && SUPERH
437	help
438	  Say Y here to enable support for the on-chip RTC found in
439	  most SuperH processors.
440
441 	  To compile this driver as a module, choose M here: the
442	  module will be called rtc-sh.
443
444config RTC_DRV_VR41XX
445	tristate "NEC VR41XX"
446	depends on CPU_VR41XX
447	help
448	  If you say Y here you will get access to the real time clock
449	  built into your NEC VR41XX CPU.
450
451	  To compile this driver as a module, choose M here: the
452	  module will be called rtc-vr41xx.
453
454config RTC_DRV_PL031
455	tristate "ARM AMBA PL031 RTC"
456	depends on ARM_AMBA
457	help
458	  If you say Y here you will get access to ARM AMBA
459	  PrimeCell PL031 RTC found on certain ARM SOCs.
460
461	  To compile this driver as a module, choose M here: the
462	  module will be called rtc-pl031.
463
464config RTC_DRV_AT32AP700X
465	tristate "AT32AP700X series RTC"
466	depends on PLATFORM_AT32AP
467	help
468	  Driver for the internal RTC (Realtime Clock) on Atmel AVR32
469	  AT32AP700x family processors.
470
471config RTC_DRV_AT91RM9200
472	tristate "AT91RM9200 or AT91SAM9RL"
473	depends on ARCH_AT91RM9200 || ARCH_AT91SAM9RL
474	help
475	  Driver for the internal RTC (Realtime Clock) module found on
476	  Atmel AT91RM9200's and AT91SAM9RL chips.  On SAM9RL chips
477	  this is powered by the backup power supply.
478
479config RTC_DRV_AT91SAM9
480	tristate "AT91SAM9x"
481	depends on ARCH_AT91 && !(ARCH_AT91RM9200 || ARCH_AT91X40)
482	help
483	  RTC driver for the Atmel AT91SAM9x internal RTT (Real Time Timer).
484	  These timers are powered by the backup power supply (such as a
485	  small coin cell battery), but do not need to be used as RTCs.
486
487	  (On AT91SAM9rl chips you probably want to use the dedicated RTC
488	  module and leave the RTT available for other uses.)
489
490config RTC_DRV_AT91SAM9_RTT
491	int
492	range 0 1
493	default 0
494	prompt "RTT module Number" if ARCH_AT91SAM9263
495	depends on RTC_DRV_AT91SAM9
496	help
497	  More than one RTT module is available.  You can choose which
498	  one will be used as an RTC.  The default of zero is normally
499	  OK to use, though some systems use that for non-RTC purposes.
500
501config RTC_DRV_AT91SAM9_GPBR
502	int
503	range 0 3 if !ARCH_AT91SAM9263
504	range 0 15 if ARCH_AT91SAM9263
505	default 0
506	prompt "Backup Register Number"
507	depends on RTC_DRV_AT91SAM9
508	help
509	  The RTC driver needs to use one of the General Purpose Backup
510	  Registers (GPBRs) as well as the RTT.  You can choose which one
511	  will be used.  The default of zero is normally OK to use, but
512	  on some systems other software needs to use that register.
513
514config RTC_DRV_BFIN
515	tristate "Blackfin On-Chip RTC"
516	depends on BLACKFIN
517	help
518	  If you say yes here you will get support for the
519	  Blackfin On-Chip Real Time Clock.
520
521	  This driver can also be built as a module. If so, the module
522	  will be called rtc-bfin.
523
524config RTC_DRV_RS5C313
525	tristate "Ricoh RS5C313"
526	depends on SH_LANDISK
527	help
528	  If you say yes here you get support for the Ricoh RS5C313 RTC chips.
529
530endif # RTC_CLASS
531