xref: /linux/drivers/rtc/Kconfig (revision 2b8232ce512105e28453f301d1510de8363bccd1)
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
23config RTC_HCTOSYS
24	bool "Set system time from RTC on startup and resume"
25	depends on RTC_CLASS = y
26	default y
27	help
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.
31
32config RTC_HCTOSYS_DEVICE
33	string "RTC used to set the system time"
34	depends on RTC_HCTOSYS = y
35	default "rtc0"
36	help
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.
40
41	  The driver for this RTC device must be loaded before late_initcall
42	  functions run, so it must usually be statically linked.
43
44	  This clock should be battery-backed, so that it reads the correct
45	  time when the system boots from a power-off state.  Otherwise, your
46	  system will need an external clock source (like an NTP server).
47
48	  If the clock you specify here is not battery backed, it may still
49	  be useful to reinitialize system time when resuming from system
50	  sleep states.  Do not specify an RTC here unless it stays powered
51	  during all this system's supported sleep states.
52
53config RTC_DEBUG
54	bool "RTC debug support"
55	depends on RTC_CLASS = y
56	help
57	  Say yes here to enable debugging support in the RTC framework
58	  and individual RTC drivers.
59
60comment "RTC interfaces"
61
62config RTC_INTF_SYSFS
63	boolean "/sys/class/rtc/rtcN (sysfs)"
64	depends on SYSFS
65	default RTC_CLASS
66	help
67	  Say yes here if you want to use your RTCs using sysfs interfaces,
68	  /sys/class/rtc/rtc0 through /sys/.../rtcN.
69
70	  This driver can also be built as a module. If so, the module
71	  will be called rtc-sysfs.
72
73config RTC_INTF_PROC
74	boolean "/proc/driver/rtc (procfs for rtc0)"
75	depends on PROC_FS
76	default RTC_CLASS
77	help
78	  Say yes here if you want to use your first RTC through the proc
79	  interface, /proc/driver/rtc.  Other RTCs will not be available
80	  through that API.
81
82	  This driver can also be built as a module. If so, the module
83	  will be called rtc-proc.
84
85config RTC_INTF_DEV
86	boolean "/dev/rtcN (character devices)"
87	default RTC_CLASS
88	help
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.
94
95	  This driver can also be built as a module. If so, the module
96	  will be called rtc-dev.
97
98config RTC_INTF_DEV_UIE_EMUL
99	bool "RTC UIE emulation on dev interface"
100	depends on RTC_INTF_DEV
101	help
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.
105
106config RTC_DRV_TEST
107	tristate "Test driver/device"
108	help
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
115	  for further details.
116
117	  This driver can also be built as a module. If so, the module
118	  will be called rtc-test.
119
120comment "I2C RTC drivers"
121	depends on I2C
122
123if I2C
124
125config RTC_DRV_DS1307
126	tristate "Dallas/Maxim DS1307/37/38/39/40, ST M41T00"
127	help
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).
133
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.
138
139	  This driver can also be built as a module. If so, the module
140	  will be called rtc-ds1307.
141
142config RTC_DRV_DS1672
143	tristate "Dallas/Maxim DS1672"
144	help
145	  If you say yes here you get support for the
146	  Dallas/Maxim DS1672 timekeeping chip.
147
148	  This driver can also be built as a module. If so, the module
149	  will be called rtc-ds1672.
150
151config RTC_DRV_MAX6900
152	tristate "Maxim 6900"
153	help
154	  If you say yes here you will get support for the
155	  Maxim MAX6900 I2C RTC chip.
156
157	  This driver can also be built as a module. If so, the module
158	  will be called rtc-max6900.
159
160config RTC_DRV_RS5C372
161	tristate "Ricoh RS5C372A/B, RV5C386, RV5C387A"
162	help
163	  If you say yes here you get support for the
164	  Ricoh RS5C372A, RS5C372B, RV5C386, and RV5C387A RTC chips.
165
166	  This driver can also be built as a module. If so, the module
167	  will be called rtc-rs5c372.
168
169config RTC_DRV_ISL1208
170	tristate "Intersil 1208"
171	help
172	  If you say yes here you get support for the
173	  Intersil 1208 RTC chip.
174
175	  This driver can also be built as a module. If so, the module
176	  will be called rtc-isl1208.
177
178config RTC_DRV_X1205
179	tristate "Xicor/Intersil X1205"
180	help
181	  If you say yes here you get support for the
182	  Xicor/Intersil X1205 RTC chip.
183
184	  This driver can also be built as a module. If so, the module
185	  will be called rtc-x1205.
186
187config RTC_DRV_PCF8563
188	tristate "Philips PCF8563/Epson RTC8564"
189	help
190	  If you say yes here you get support for the
191	  Philips PCF8563 RTC chip. The Epson RTC8564
192	  should work as well.
193
194	  This driver can also be built as a module. If so, the module
195	  will be called rtc-pcf8563.
196
197config RTC_DRV_PCF8583
198	tristate "Philips PCF8583"
199	help
200	  If you say yes here you get support for the Philips PCF8583
201	  RTC chip found on Acorn RiscPCs. This driver supports the
202	  platform specific method of retrieving the current year from
203	  the RTC's SRAM. It will work on other platforms with the same
204	  chip, but the year will probably have to be tweaked.
205
206	  This driver can also be built as a module. If so, the module
207	  will be called rtc-pcf8583.
208
209config RTC_DRV_M41T80
210	tristate "ST M41T80 series RTC"
211	help
212	  If you say Y here you will get support for the
213	  ST M41T80 RTC chips series. Currently following chips are
214	  supported: M41T80, M41T81, M41T82, M41T83, M41ST84, M41ST85
215	  and M41ST87.
216
217	  This driver can also be built as a module. If so, the module
218	  will be called rtc-m41t80.
219
220config RTC_DRV_M41T80_WDT
221	bool "ST M41T80 series RTC watchdog timer"
222	depends on RTC_DRV_M41T80
223	help
224	  If you say Y here you will get support for the
225	  watchdog timer in ST M41T80 RTC chips series.
226
227config RTC_DRV_TWL92330
228	boolean "TI TWL92330/Menelaus"
229	depends on MENELAUS
230	help
231	  If you say yes here you get support for the RTC on the
232	  TWL92330 "Menelaus" power mangement chip, used with OMAP2
233	  platforms.  The support is integrated with the rest of
234	  the Menelaus driver; it's not separate module.
235
236endif # I2C
237
238comment "SPI RTC drivers"
239
240if SPI_MASTER
241
242config RTC_DRV_RS5C348
243	tristate "Ricoh RS5C348A/B"
244	help
245	  If you say yes here you get support for the
246	  Ricoh RS5C348A and RS5C348B RTC chips.
247
248	  This driver can also be built as a module. If so, the module
249	  will be called rtc-rs5c348.
250
251config RTC_DRV_MAX6902
252	tristate "Maxim 6902"
253	help
254	  If you say yes here you will get support for the
255	  Maxim MAX6902 SPI RTC chip.
256
257	  This driver can also be built as a module. If so, the module
258	  will be called rtc-max6902.
259
260endif # SPI_MASTER
261
262comment "Platform RTC drivers"
263
264# this 'CMOS' RTC driver is arch dependent because <asm-generic/rtc.h>
265# requires <asm/mc146818rtc.h> defining CMOS_READ/CMOS_WRITE, and a
266# global rtc_lock ... it's not yet just another platform_device.
267
268config RTC_DRV_CMOS
269	tristate "PC-style 'CMOS'"
270	depends on X86 || ALPHA || ARM || M32R || ATARI || PPC || MIPS
271	help
272	  Say "yes" here to get direct support for the real time clock
273	  found in every PC or ACPI-based system, and some other boards.
274	  Specifically the original MC146818, compatibles like those in
275	  PC south bridges, the DS12887 or M48T86, some multifunction
276	  or LPC bus chips, and so on.
277
278	  Your system will need to define the platform device used by
279	  this driver, otherwise it won't be accessible.  This means
280	  you can safely enable this driver if you don't know whether
281	  or not your board has this kind of hardware.
282
283	  This driver can also be built as a module. If so, the module
284	  will be called rtc-cmos.
285
286config RTC_DRV_DS1216
287	tristate "Dallas DS1216"
288	depends on SNI_RM
289	help
290	  If you say yes here you get support for the Dallas DS1216 RTC chips.
291
292config RTC_DRV_DS1553
293	tristate "Dallas DS1553"
294	help
295	  If you say yes here you get support for the
296	  Dallas DS1553 timekeeping chip.
297
298	  This driver can also be built as a module. If so, the module
299	  will be called rtc-ds1553.
300
301config RTC_DRV_STK17TA8
302	tristate "Simtek STK17TA8"
303	depends on RTC_CLASS
304	help
305	  If you say yes here you get support for the
306	  Simtek STK17TA8 timekeeping chip.
307
308	  This driver can also be built as a module. If so, the module
309	  will be called rtc-stk17ta8.
310
311config RTC_DRV_DS1742
312	tristate "Dallas DS1742/1743"
313	help
314	  If you say yes here you get support for the
315	  Dallas DS1742/1743 timekeeping chip.
316
317	  This driver can also be built as a module. If so, the module
318	  will be called rtc-ds1742.
319
320config RTC_DRV_M48T86
321	tristate "ST M48T86/Dallas DS12887"
322	help
323	  If you say Y here you will get support for the
324	  ST M48T86 and Dallas DS12887 RTC chips.
325
326	  This driver can also be built as a module. If so, the module
327	  will be called rtc-m48t86.
328
329config RTC_DRV_M48T59
330	tristate "ST M48T59"
331	help
332	  If you say Y here you will get support for the
333	  ST M48T59 RTC chip.
334
335	  This driver can also be built as a module, if so, the module
336	  will be called "rtc-m48t59".
337
338config RTC_DRV_V3020
339	tristate "EM Microelectronic V3020"
340	help
341	  If you say yes here you will get support for the
342	  EM Microelectronic v3020 RTC chip.
343
344	  This driver can also be built as a module. If so, the module
345	  will be called rtc-v3020.
346
347comment "on-CPU RTC drivers"
348
349config RTC_DRV_OMAP
350	tristate "TI OMAP1"
351	depends on ARCH_OMAP15XX || ARCH_OMAP16XX || ARCH_OMAP730
352	help
353	  Say "yes" here to support the real time clock on TI OMAP1 chips.
354	  This driver can also be built as a module called rtc-omap.
355
356config RTC_DRV_S3C
357	tristate "Samsung S3C series SoC RTC"
358	depends on ARCH_S3C2410
359	help
360	  RTC (Realtime Clock) driver for the clock inbuilt into the
361	  Samsung S3C24XX series of SoCs. This can provide periodic
362	  interrupt rates from 1Hz to 64Hz for user programs, and
363	  wakeup from Alarm.
364
365	  The driver currently supports the common features on all the
366	  S3C24XX range, such as the S3C2410, S3C2412, S3C2413, S3C2440
367	  and S3C2442.
368
369	  This driver can also be build as a module. If so, the module
370	  will be called rtc-s3c.
371
372config RTC_DRV_EP93XX
373	tristate "Cirrus Logic EP93XX"
374	depends on ARCH_EP93XX
375	help
376	  If you say yes here you get support for the
377	  RTC embedded in the Cirrus Logic EP93XX processors.
378
379	  This driver can also be built as a module. If so, the module
380	  will be called rtc-ep93xx.
381
382config RTC_DRV_SA1100
383	tristate "SA11x0/PXA2xx"
384	depends on ARCH_SA1100 || ARCH_PXA
385	help
386	  If you say Y here you will get access to the real time clock
387	  built into your SA11x0 or PXA2xx CPU.
388
389	  To compile this driver as a module, choose M here: the
390	  module will be called rtc-sa1100.
391
392config RTC_DRV_SH
393	tristate "SuperH On-Chip RTC"
394	depends on RTC_CLASS && (CPU_SH3 || CPU_SH4)
395	help
396	  Say Y here to enable support for the on-chip RTC found in
397	  most SuperH processors.
398
399 	  To compile this driver as a module, choose M here: the
400	  module will be called rtc-sh.
401
402config RTC_DRV_VR41XX
403	tristate "NEC VR41XX"
404	depends on CPU_VR41XX
405	help
406	  If you say Y here you will get access to the real time clock
407	  built into your NEC VR41XX CPU.
408
409	  To compile this driver as a module, choose M here: the
410	  module will be called rtc-vr41xx.
411
412config RTC_DRV_PL031
413	tristate "ARM AMBA PL031 RTC"
414	depends on ARM_AMBA
415	help
416	  If you say Y here you will get access to ARM AMBA
417	  PrimeCell PL031 RTC found on certain ARM SOCs.
418
419	  To compile this driver as a module, choose M here: the
420	  module will be called rtc-pl031.
421
422config RTC_DRV_AT32AP700X
423	tristate "AT32AP700X series RTC"
424	depends on PLATFORM_AT32AP
425	help
426	  Driver for the internal RTC (Realtime Clock) on Atmel AVR32
427	  AT32AP700x family processors.
428
429config RTC_DRV_AT91RM9200
430	tristate "AT91RM9200"
431	depends on ARCH_AT91RM9200
432	help
433	  Driver for the Atmel AT91RM9200's internal RTC (Realtime Clock).
434
435config RTC_DRV_BFIN
436	tristate "Blackfin On-Chip RTC"
437	depends on BFIN
438	help
439	  If you say yes here you will get support for the
440	  Blackfin On-Chip Real Time Clock.
441
442	  This driver can also be built as a module. If so, the module
443	  will be called rtc-bfin.
444
445config RTC_DRV_RS5C313
446	tristate "Ricoh RS5C313"
447	depends on SH_LANDISK
448	help
449	  If you say yes here you get support for the Ricoh RS5C313 RTC chips.
450
451endif # RTC_CLASS
452