From aaaf5fbf56f16c81a653713cc333b18ad6e25ea9 Mon Sep 17 00:00:00 2001 From: Joshua Kinard Date: Mon, 16 Feb 2015 16:00:26 -0800 Subject: rtc: add driver for DS1685 family of real time clocks This adds a driver for the Dallas/Maxim DS1685-family of RTC chips. It supports the DS1685/DS1687, DS1688/DS1691, DS1689/DS1693, DS17285/DS17287, DS17485/DS17487, and DS17885/DS17887 RTC chips. These chips are commonly found in SGI O2 and SGI Octane systems. It was originally derived from a driver patch submitted by Matthias Fuchs many years ago for use in EPPC-405-UC modules, which also used these RTCs. In addition to the time-keeping functions, this RTC also handles the shutdown mechanism of the O2 and Octane and acts as a partial NVRAM for the boot PROMS in these systems. Verified on both an SGI O2 and an SGI Octane. Signed-off-by: Joshua Kinard Cc: Ralf Baechle Cc: Alessandro Zummo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rtc/Kconfig | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 90 insertions(+) (limited to 'drivers/rtc/Kconfig') diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index 3bc9ddbe5cf7..0cf2e1d9cb17 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -801,6 +801,96 @@ config RTC_DRV_DS1553 This driver can also be built as a module. If so, the module will be called rtc-ds1553. +config RTC_DRV_DS1685_FAMILY + tristate "Dallas/Maxim DS1685 Family" + help + If you say yes here you get support for the Dallas/Maxim DS1685 + family of real time chips. This family includes the DS1685/DS1687, + DS1689/DS1693, DS17285/DS17287, DS17485/DS17487, and + DS17885/DS17887 chips. + + This driver can also be built as a module. If so, the module + will be called rtc-ds1685. + +choice + prompt "Subtype" + depends on RTC_DRV_DS1685_FAMILY + default RTC_DRV_DS1685 + +config RTC_DRV_DS1685 + bool "DS1685/DS1687" + help + This enables support for the Dallas/Maxim DS1685/DS1687 real time + clock chip. + + This chip is commonly found in SGI O2 (IP32) and SGI Octane (IP30) + systems, as well as EPPC-405-UC modules by electronic system design + GmbH. + +config RTC_DRV_DS1689 + bool "DS1689/DS1693" + help + This enables support for the Dallas/Maxim DS1689/DS1693 real time + clock chip. + + This is an older RTC chip, supplanted by the DS1685/DS1687 above, + which supports a few minor features such as Vcc, Vbat, and Power + Cycle counters, plus a customer-specific, 8-byte ROM/Serial number. + + It also works for the even older DS1688/DS1691 RTC chips, which are + virtually the same and carry the same model number. Both chips + have 114 bytes of user NVRAM. + +config RTC_DRV_DS17285 + bool "DS17285/DS17287" + help + This enables support for the Dallas/Maxim DS17285/DS17287 real time + clock chip. + + This chip features 2kb of extended NV-SRAM. It may possibly be + found in some SGI O2 systems (rare). + +config RTC_DRV_DS17485 + bool "DS17485/DS17487" + help + This enables support for the Dallas/Maxim DS17485/DS17487 real time + clock chip. + + This chip features 4kb of extended NV-SRAM. + +config RTC_DRV_DS17885 + bool "DS17885/DS17887" + help + This enables support for the Dallas/Maxim DS17885/DS17887 real time + clock chip. + + This chip features 8kb of extended NV-SRAM. + +endchoice + +config RTC_DS1685_PROC_REGS + bool "Display register values in /proc" + depends on RTC_DRV_DS1685_FAMILY && PROC_FS + help + Enable this to display a readout of all of the RTC registers in + /proc/drivers/rtc. Keep in mind that this can potentially lead + to lost interrupts, as reading Control Register C will clear + all pending IRQ flags. + + Unless you are debugging this driver, choose N. + +config RTC_DS1685_SYSFS_REGS + bool "SysFS access to RTC register bits" + depends on RTC_DRV_DS1685_FAMILY && SYSFS + help + Enable this to provide access to the RTC control register bits + in /sys. Some of the bits are read-write, others are read-only. + + Keep in mind that reading Control C's bits automatically clears + all pending IRQ flags - this can cause lost interrupts. + + If you know that you need access to these bits, choose Y, Else N. + config RTC_DRV_DS1742 tristate "Maxim/Dallas DS1742/1743" depends on HAS_IOMEM -- cgit v1.2.3