diff options
author | Joshua Kinard <kumba@gentoo.org> | 2015-02-16 16:00:26 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-02-16 17:56:05 -0800 |
commit | aaaf5fbf56f16c81a653713cc333b18ad6e25ea9 (patch) | |
tree | 5416188285df8877c1e069f3db9a24541c2b057f /drivers/rtc | |
parent | befeb596a7224119b60499eb20c7545f7a73f104 (diff) |
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 <kumba@gentoo.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/rtc')
-rw-r--r-- | drivers/rtc/Kconfig | 90 | ||||
-rw-r--r-- | drivers/rtc/Makefile | 1 | ||||
-rw-r--r-- | drivers/rtc/rtc-ds1685.c | 2252 |
3 files changed, 2343 insertions, 0 deletions
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 diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index 99ded8b75e95..69c87062b098 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -54,6 +54,7 @@ obj-$(CONFIG_RTC_DRV_DS1390) += rtc-ds1390.o obj-$(CONFIG_RTC_DRV_DS1511) += rtc-ds1511.o obj-$(CONFIG_RTC_DRV_DS1553) += rtc-ds1553.o obj-$(CONFIG_RTC_DRV_DS1672) += rtc-ds1672.o +obj-$(CONFIG_RTC_DRV_DS1685_FAMILY) += rtc-ds1685.o obj-$(CONFIG_RTC_DRV_DS1742) += rtc-ds1742.o obj-$(CONFIG_RTC_DRV_DS2404) += rtc-ds2404.o obj-$(CONFIG_RTC_DRV_DS3232) += rtc-ds3232.o diff --git a/drivers/rtc/rtc-ds1685.c b/drivers/rtc/rtc-ds1685.c new file mode 100644 index 000000000000..8c3bfcb115b7 --- /dev/null +++ b/drivers/rtc/rtc-ds1685.c @@ -0,0 +1,2252 @@ +/* + * An rtc driver for the Dallas/Maxim DS1685/DS1687 and related real-time + * chips. + * + * Copyright (C) 2011-2014 Joshua Kinard <kumba@gentoo.org>. + * Copyright (C) 2009 Matthias Fuchs <matthias.fuchs@esd-electronics.com>. + * + * References: + * DS1685/DS1687 3V/5V Real-Time Clocks, 19-5215, Rev 4/10. + * DS17x85/DS17x87 3V/5V Real-Time Clocks, 19-5222, Rev 4/10. + * DS1689/DS1693 3V/5V Serialized Real-Time Clocks, Rev 112105. + * Application Note 90, Using the Multiplex Bus RTC Extended Features. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/bcd.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/rtc.h> +#include <linux/workqueue.h> + +#include <linux/rtc/ds1685.h> + +#ifdef CONFIG_PROC_FS +#include <linux/proc_fs.h> +#endif + +#define DRV_VERSION "0.42.0" + + +/* ----------------------------------------------------------------------- */ +/* Standard read/write functions if platform does not provide overrides */ + +/** + * ds1685_read - read a value from an rtc register. + * @rtc: pointer to the ds1685 rtc structure. + * @reg: the register address to read. + */ +static u8 +ds1685_read(struct ds1685_priv *rtc, int reg) +{ + return readb((u8 __iomem *)rtc->regs + + (reg * rtc->regstep)); +} + +/** + * ds1685_write - write a value to an rtc register. + * @rtc: pointer to the ds1685 rtc structure. + * @reg: the register address to write. + * @value: value to write to the register. + */ +static void +ds1685_write(struct ds1685_priv *rtc, int reg, u8 value) +{ + writeb(value, ((u8 __iomem *)rtc->regs + + (reg * rtc->regstep))); +} +/* ----------------------------------------------------------------------- */ + + +/* ----------------------------------------------------------------------- */ +/* Inlined functions */ + +/** + * ds1685_rtc_bcd2bin - bcd2bin wrapper in case platform doesn't support BCD. + * @rtc: pointer to the ds1685 rtc structure. + * @val: u8 time value to consider converting. + * @bcd_mask: u8 mask value if BCD mode is used. + * @bin_mask: u8 mask value if BIN mode is used. + * + * Returns the value, converted to BIN if originally in BCD and bcd_mode TRUE. + */ +static inline u8 +ds1685_rtc_bcd2bin(struct ds1685_priv *rtc, u8 val, u8 bcd_mask, u8 bin_mask) +{ + if (rtc->bcd_mode) + return (bcd2bin(val) & bcd_mask); + + return (val & bin_mask); +} + +/** + * ds1685_rtc_bin2bcd - bin2bcd wrapper in case platform doesn't support BCD. + * @rtc: pointer to the ds1685 rtc structure. + * @val: u8 time value to consider converting. + * @bin_mask: u8 mask value if BIN mode is used. + * @bcd_mask: u8 mask value if BCD mode is used. + * + * Returns the value, converted to BCD if originally in BIN and bcd_mode TRUE. + */ +static inline u8 +ds1685_rtc_bin2bcd(struct ds1685_priv *rtc, u8 val, u8 bin_mask, u8 bcd_mask) +{ + if (rtc->bcd_mode) + return (bin2bcd(val) & bcd_mask); + + return (val & bin_mask); +} + +/** + * ds1685_rtc_switch_to_bank0 - switch the rtc to bank 0. + * @rtc: pointer to the ds1685 rtc structure. + */ +static inline void +ds1685_rtc_switch_to_bank0(struct ds1685_priv *rtc) +{ + rtc->write(rtc, RTC_CTRL_A, + (rtc->read(rtc, RTC_CTRL_A) & ~(RTC_CTRL_A_DV0))); +} + +/** + * ds1685_rtc_switch_to_bank1 - switch the rtc to bank 1. + * @rtc: pointer to the ds1685 rtc structure. + */ +static inline void +ds1685_rtc_switch_to_bank1(struct ds1685_priv *rtc) +{ + rtc->write(rtc, RTC_CTRL_A, + (rtc->read(rtc, RTC_CTRL_A) | RTC_CTRL_A_DV0)); +} + +/** + * ds1685_rtc_begin_data_access - prepare the rtc for data access. + * @rtc: pointer to the ds1685 rtc structure. + * + * This takes several steps to prepare the rtc for access to get/set time + * and alarm values from the rtc registers: + * - Sets the SET bit in Control Register B. + * - Reads Ext Control Register 4A and checks the INCR bit. + * - If INCR is active, a short delay is added before Ext Control Register 4A + * is read again in a loop until INCR is inactive. + * - Switches the rtc to bank 1. This allows access to all relevant + * data for normal rtc operation, as bank 0 contains only the nvram. + */ +static inline void +ds1685_rtc_begin_data_access(struct ds1685_priv *rtc) +{ + /* Set the SET bit in Ctrl B */ + rtc->write(rtc, RTC_CTRL_B, + (rtc->read(rtc, RTC_CTRL_B) | RTC_CTRL_B_SET)); + + /* Read Ext Ctrl 4A and check the INCR bit to avoid a lockout. */ + while (rtc->read(rtc, RTC_EXT_CTRL_4A) & RTC_CTRL_4A_INCR) + cpu_relax(); + + /* Switch to Bank 1 */ + ds1685_rtc_switch_to_bank1(rtc); +} + +/** + * ds1685_rtc_end_data_access - end data access on the rtc. + * @rtc: pointer to the ds1685 rtc structure. + * + * This ends what was started by ds1685_rtc_begin_data_access: + * - Switches the rtc back to bank 0. + * - Clears the SET bit in Control Register B. + */ +static inline void +ds1685_rtc_end_data_access(struct ds1685_priv *rtc) +{ + /* Switch back to Bank 0 */ + ds1685_rtc_switch_to_bank1(rtc); + + /* Clear the SET bit in Ctrl B */ + rtc->write(rtc, RTC_CTRL_B, + (rtc->read(rtc, RTC_CTRL_B) & ~(RTC_CTRL_B_SET))); +} + +/** + * ds1685_rtc_begin_ctrl_access - prepare the rtc for ctrl access. + * @rtc: pointer to the ds1685 rtc structure. + * @flags: irq flags variable for spin_lock_irqsave. + * + * This takes several steps to prepare the rtc for access to read just the + * control registers: + * - Sets a spinlock on the rtc IRQ. + * - Switches the rtc to bank 1. This allows access to the two extended + * control registers. + * + * Only use this where you are certain another lock will not be held. + */ +static inline void +ds1685_rtc_begin_ctrl_access(struct ds1685_priv *rtc, unsigned long flags) +{ + spin_lock_irqsave(&rtc->lock, flags); + ds1685_rtc_switch_to_bank1(rtc); +} + +/** + * ds1685_rtc_end_ctrl_access - end ctrl access on the rtc. + * @rtc: pointer to the ds1685 rtc structure. + * @flags: irq flags variable for spin_unlock_irqrestore. + * + * This ends what was started by ds1685_rtc_begin_ctrl_access: + * - Switches the rtc back to bank 0. + * - Unsets the spinlock on the rtc IRQ. + */ +static inline void +ds1685_rtc_end_ctrl_access(struct ds1685_priv *rtc, unsigned long flags) +{ + ds1685_rtc_switch_to_bank0(rtc); + spin_unlock_irqrestore(&rtc->lock, flags); +} + +/** + * ds1685_rtc_get_ssn - retrieve the silicon serial number. + * @rtc: pointer to the ds1685 rtc structure. + * @ssn: u8 array to hold the bits of the silicon serial number. + * + * This number starts at 0x40, and is 8-bytes long, ending at 0x47. The + * first byte is the model number, the next six bytes are the serial number + * digits, and the final byte is a CRC check byte. Together, they form the + * silicon serial number. + * + * These values are stored in bank1, so ds1685_rtc_switch_to_bank1 must be + * called first before calling this function, else data will be read out of + * the bank0 NVRAM. Be sure to call ds1685_rtc_switch_to_bank0 when done. + */ +static inline void +ds1685_rtc_get_ssn(struct ds1685_priv *rtc, u8 *ssn) +{ + ssn[0] = rtc->read(rtc, RTC_BANK1_SSN_MODEL); + ssn[1] = rtc->read(rtc, RTC_BANK1_SSN_BYTE_1); + ssn[2] = rtc->read(rtc, RTC_BANK1_SSN_BYTE_2); + ssn[3] = rtc->read(rtc, RTC_BANK1_SSN_BYTE_3); + ssn[4] = rtc->read(rtc, RTC_BANK1_SSN_BYTE_4); + ssn[5] = rtc->read(rtc, RTC_BANK1_SSN_BYTE_5); + ssn[6] = rtc->read(rtc, RTC_BANK1_SSN_BYTE_6); + ssn[7] = rtc->read(rtc, RTC_BANK1_SSN_CRC); +} +/* ----------------------------------------------------------------------- */ + + +/* ----------------------------------------------------------------------- */ +/* Read/Set Time & Alarm functions */ + +/** + * ds1685_rtc_read_time - reads the time registers. + * @dev: pointer to device structure. + * @tm: pointer to rtc_time structure. + */ +static int +ds1685_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct platform_device *pdev = to_platform_device(dev); + struct ds1685_priv *rtc = platform_get_drvdata(pdev); + u8 ctrlb, century; + u8 seconds, minutes, hours, wday, mday, month, years; + + /* Fetch the time info from the RTC registers. */ + ds1685_rtc_begin_data_access(rtc); + seconds = rtc->read(rtc, RTC_SECS); + minutes = rtc->read(rtc, RTC_MINS); + hours = rtc->read(rtc, RTC_HRS); + wday = rtc->read(rtc, RTC_WDAY); + mday = rtc->read(rtc, RTC_MDAY); + month = rtc->read(rtc, RTC_MONTH); + years = rtc->read(rtc, RTC_YEAR); + century = rtc->read(rtc, RTC_CENTURY); + ctrlb = rtc->read(rtc, RTC_CTRL_B); + ds1685_rtc_end_data_access(rtc); + + /* bcd2bin if needed, perform fixups, and store to rtc_time. */ + years = ds1685_rtc_bcd2bin(rtc, years, RTC_YEAR_BCD_MASK, + RTC_YEAR_BIN_MASK); + century = ds1685_rtc_bcd2bin(rtc, century, RTC_CENTURY_MASK, + RTC_CENTURY_MASK); + tm->tm_sec = ds1685_rtc_bcd2bin(rtc, seconds, RTC_SECS_BCD_MASK, + RTC_SECS_BIN_MASK); + tm->tm_min = ds1685_rtc_bcd2bin(rtc, minutes, RTC_MINS_BCD_MASK, + RTC_MINS_BIN_MASK); + tm->tm_hour = ds1685_rtc_bcd2bin(rtc, hours, RTC_HRS_24_BCD_MASK, + RTC_HRS_24_BIN_MASK); + tm->tm_wday = (ds1685_rtc_bcd2bin(rtc, wday, RTC_WDAY_MASK, + RTC_WDAY_MASK) - 1); + tm->tm_mday = ds1685_rtc_bcd2bin(rtc, mday, RTC_MDAY_BCD_MASK, + RTC_MDAY_BIN_MASK); + tm->tm_mon = (ds1685_rtc_bcd2bin(rtc, month, RTC_MONTH_BCD_MASK, + RTC_MONTH_BIN_MASK) - 1); + tm->tm_year = ((years + (century * 100)) - 1900); + tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); + tm->tm_isdst = 0; /* RTC has hardcoded timezone, so don't use. */ + + return rtc_valid_tm(tm); +} + +/** + * ds1685_rtc_set_time - sets the time registers. + * @dev: pointer to device structure. + * @tm: pointer to rtc_time structure. + */ +static int +ds1685_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct platform_device *pdev = to_platform_device(dev); + struct ds1685_priv *rtc = platform_get_drvdata(pdev); + u8 ctrlb, seconds, minutes, hours, wday, mday, month, years, century; + + /* Fetch the time info from rtc_time. */ + seconds = ds1685_rtc_bin2bcd(rtc, tm->tm_sec, RTC_SECS_BIN_MASK, + RTC_SECS_BCD_MASK); + minutes = ds1685_rtc_bin2bcd(rtc, tm->tm_min, RTC_MINS_BIN_MASK, + RTC_MINS_BCD_MASK); + hours = ds1685_rtc_bin2bcd(rtc, tm->tm_hour, RTC_HRS_24_BIN_MASK, + RTC_HRS_24_BCD_MASK); + wday = ds1685_rtc_bin2bcd(rtc, (tm->tm_wday + 1), RTC_WDAY_MASK, + RTC_WDAY_MASK); + mday = ds1685_rtc_bin2bcd(rtc, tm->tm_mday, RTC_MDAY_BIN_MASK, + RTC_MDAY_BCD_MASK); + month = ds1685_rtc_bin2bcd(rtc, (tm->tm_mon + 1), RTC_MONTH_BIN_MASK, + RTC_MONTH_BCD_MASK); + years = ds1685_rtc_bin2bcd(rtc, (tm->tm_year % 100), + RTC_YEAR_BIN_MASK, RTC_YEAR_BCD_MASK); + century = ds1685_rtc_bin2bcd(rtc, ((tm->tm_year + 1900) / 100), + RTC_CENTURY_MASK, RTC_CENTURY_MASK); + + /* + * Perform Sanity Checks: + * - Months: !> 12, Month Day != 0. + * - Month Day !> Max days in current month. + * - Hours !>= 24, Mins !>= 60, Secs !>= 60, & Weekday !> 7. + */ + if ((tm->tm_mon > 11) || (mday == 0)) + return -EDOM; + + if (tm->tm_mday > rtc_month_days(tm->tm_mon, tm->tm_year)) + return -EDOM; + + if ((tm->tm_hour >= 24) || (tm->tm_min >= 60) || + (tm->tm_sec >= 60) || (wday > 7)) + return -EDOM; + + /* + * Set the data mode to use and store the time values in the + * RTC registers. + */ + ds1685_rtc_begin_data_access(rtc); + ctrlb = rtc->read(rtc, RTC_CTRL_B); + if (rtc->bcd_mode) + ctrlb &= ~(RTC_CTRL_B_DM); + else + ctrlb |= RTC_CTRL_B_DM; + rtc->write(rtc, RTC_CTRL_B, ctrlb); + rtc->write(rtc, RTC_SECS, seconds); + rtc->write(rtc, RTC_MINS, minutes); + rtc->write(rtc, RTC_HRS, hours); + rtc->write(rtc, RTC_WDAY, wday); + rtc->write(rtc, RTC_MDAY, mday); + rtc->write(rtc, RTC_MONTH, month); + rtc->write(rtc, RTC_YEAR, years); + rtc->write(rtc, RTC_CENTURY, century); + ds1685_rtc_end_data_access(rtc); + + return 0; +} + +/** + * ds1685_rtc_read_alarm - reads the alarm registers. + * @dev: pointer to device structure. + * @alrm: pointer to rtc_wkalrm structure. + * + * There are three primary alarm registers: seconds, minutes, and hours. + * A fourth alarm register for the month date is also available in bank1 for + * kickstart/wakeup features. The DS1685/DS1687 manual states that a + * "don't care" value ranging from 0xc0 to 0xff may be written into one or + * more of the three alarm bytes to act as a wildcard value. The fourth + * byte doesn't support a "don't care" value. + */ +static int +ds1685_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct platform_device *pdev = to_platform_device(dev); + struct ds1685_priv *rtc = platform_get_drvdata(pdev); + u8 seconds, minutes, hours, mday, ctrlb, ctrlc; + + /* Fetch the alarm info from the RTC alarm registers. */ + ds1685_rtc_begin_data_access(rtc); + seconds = rtc->read(rtc, RTC_SECS_ALARM); + minutes = rtc->read(rtc, RTC_MINS_ALARM); + hours = rtc->read(rtc, RTC_HRS_ALARM); + mday = rtc->read(rtc, RTC_MDAY_ALARM); + ctrlb = rtc->read(rtc, RTC_CTRL_B); + ctrlc = rtc->read(rtc, RTC_CTRL_C); + ds1685_rtc_end_data_access(rtc); + + /* Check month date. */ + if (!(mday >= 1) && (mday <= 31)) + return -EDOM; + + /* + * Check the three alarm bytes. + * + * The Linux RTC system doesn't support the "don't care" capability + * of this RTC chip. We check for it anyways in case support is + * added in the future. + */ + if (unlikely((seconds >= 0xc0) && (seconds <= 0xff))) + alrm->time.tm_sec = -1; + else + alrm->time.tm_sec = ds1685_rtc_bcd2bin(rtc, seconds, + RTC_SECS_BCD_MASK, + RTC_SECS_BIN_MASK); + + if (unlikely((minutes >= 0xc0) && (minutes <= 0xff))) + alrm->time.tm_min = -1; + else + alrm->time.tm_min = ds1685_rtc_bcd2bin(rtc, minutes, + RTC_MINS_BCD_MASK, + RTC_MINS_BIN_MASK); + + if (unlikely((hours >= 0xc0) && (hours <= 0xff))) + alrm->time.tm_hour = -1; + else + alrm->time.tm_hour = ds1685_rtc_bcd2bin(rtc, hours, + RTC_HRS_24_BCD_MASK, + RTC_HRS_24_BIN_MASK); + + /* Write the data to rtc_wkalrm. */ + alrm->time.tm_mday = ds1685_rtc_bcd2bin(rtc, mday, RTC_MDAY_BCD_MASK, + RTC_MDAY_BIN_MASK); + alrm->time.tm_mon = -1; + alrm->time.tm_year = -1; + alrm->time.tm_wday = -1; + alrm->time.tm_yday = -1; + alrm->time.tm_isdst = -1; + alrm->enabled = !!(ctrlb & RTC_CTRL_B_AIE); + alrm->pending = !!(ctrlc & RTC_CTRL_C_AF); + + return 0; +} + +/** + * ds1685_rtc_set_alarm - sets the alarm in registers. + * @dev: pointer to device structure. + * @alrm: pointer to rtc_wkalrm structure. + */ +static int +ds1685_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct platform_device *pdev = to_platform_device(dev); + struct ds1685_priv *rtc = platform_get_drvdata(pdev); + u8 ctrlb, seconds, minutes, hours, mday; + + /* Fetch the alarm info and convert to BCD. */ + seconds = ds1685_rtc_bin2bcd(rtc, alrm->time.tm_sec, + RTC_SECS_BIN_MASK, + RTC_SECS_BCD_MASK); + minutes = ds1685_rtc_bin2bcd(rtc, alrm->time.tm_min, + RTC_MINS_BIN_MASK, + RTC_MINS_BCD_MASK); + hours = ds1685_rtc_bin2bcd(rtc, alrm->time.tm_hour, + RTC_HRS_24_BIN_MASK, + RTC_HRS_24_BCD_MASK); + mday = ds1685_rtc_bin2bcd(rtc, alrm->time.tm_mday, + RTC_MDAY_BIN_MASK, + RTC_MDAY_BCD_MASK); + + /* Check the month date for validity. */ + if (!(mday >= 1) && (mday <= 31)) + return -EDOM; + + /* + * Check the three alarm bytes. + * + * The Linux RTC system doesn't support the "don't care" capability + * of this RTC chip because rtc_valid_tm tries to validate every + * field, and we only support four fields. We put the support + * here anyways for the future. + */ + if (unlikely((seconds >= 0xc0) && (seconds <= 0xff))) + seconds = 0xff; + + if (unlikely((minutes >= 0xc0) && (minutes <= 0xff))) + minutes = 0xff; + + if (unlikely((hours >= 0xc0) && (hours <= 0xff))) + hours = 0xff; + + alrm->time.tm_mon = -1; + alrm->time.tm_year = -1; + alrm->time.tm_wday = -1; + alrm->time.tm_yday = -1; + alrm->time.tm_isdst = -1; + + /* Disable the alarm interrupt first. */ + ds1685_rtc_begin_data_access(rtc); + ctrlb = rtc->read(rtc, RTC_CTRL_B); + rtc->write(rtc, RTC_CTRL_B, (ctrlb & ~(RTC_CTRL_B_AIE))); + + /* Read ctrlc to clear RTC_CTRL_C_AF. */ + rtc->read(rtc, RTC_CTRL_C); + + /* + * Set the data mode to use and store the time values in the + * RTC registers. + */ + ctrlb = rtc->read(rtc, RTC_CTRL_B); + if (rtc->bcd_mode) + ctrlb &= ~(RTC_CTRL_B_DM); + else + ctrlb |= RTC_CTRL_B_DM; + rtc->write(rtc, RTC_CTRL_B, ctrlb); + rtc->write(rtc, RTC_SECS_ALARM, seconds); + rtc->write(rtc, RTC_MINS_ALARM, minutes); + rtc->write(rtc, RTC_HRS_ALARM, hours); + rtc->write(rtc, RTC_MDAY_ALARM, mday); + + /* Re-enable the alarm if needed. */ + if (alrm->enabled) { + ctrlb = rtc->read(rtc, RTC_CTRL_B); + ctrlb |= RTC_CTRL_B_AIE; + rtc->write(rtc, RTC_CTRL_B, ctrlb); + } + + /* Done! */ + ds1685_rtc_end_data_access(rtc); + + return 0; +} +/* ----------------------------------------------------------------------- */ + + +/* ----------------------------------------------------------------------- */ +/* /dev/rtcX Interface functions */ + +#ifdef CONFIG_RTC_INTF_DEV +/** + * ds1685_rtc_alarm_irq_enable - replaces ioctl() RTC_AIE on/off. + * @dev: pointer to device structure. + * @enabled: flag indicating whether to enable or disable. + */ +static int +ds1685_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) +{ + struct ds1685_priv *rtc = dev_get_drvdata(dev); + unsigned long flags = 0; + + /* Enable/disable the Alarm IRQ-Enable flag. */ + spin_lock_irqsave(&rtc->lock, flags); + + /* Flip the requisite interrupt-enable bit. */ + if (enabled) + rtc->write(rtc, RTC_CTRL_B, (rtc->read(rtc, RTC_CTRL_B) | + RTC_CTRL_B_AIE)); + else + rtc->write(rtc, RTC_CTRL_B, (rtc->read(rtc, RTC_CTRL_B) & + ~(RTC_CTRL_B_AIE))); + + /* Read Control C to clear all the flag bits. */ + rtc->read(rtc, RTC_CTRL_C); + spin_unlock_irqrestore(&rtc->lock, flags); + + return 0; +} +#endif +/* ----------------------------------------------------------------------- */ + + +/* ----------------------------------------------------------------------- */ +/* IRQ handler & workqueue. */ + +/** + * ds1685_rtc_irq_handler - IRQ handler. + * @irq: IRQ number. + * @dev_id: platform device pointer. + */ +static irqreturn_t +ds1685_rtc_irq_handler(int irq, void *dev_id) +{ + struct platform_device *pdev = dev_id; + struct ds1685_priv *rtc = platform_get_drvdata(pdev); + u8 ctrlb, ctrlc; + unsigned long events = 0; + u8 num_irqs = 0; + + /* Abort early if the device isn't ready yet (i.e., DEBUG_SHIRQ). */ + if (unlikely(!rtc)) + return IRQ_HANDLED; + + /* Ctrlb holds the interrupt-enable bits and ctrlc the flag bits. */ + spin_lock(&rtc->lock); + ctrlb = rtc->read(rtc, RTC_CTRL_B); + ctrlc = rtc->read(rtc, RTC_CTRL_C); + + /* Is the IRQF bit set? */ + if (likely(ctrlc & RTC_CTRL_C_IRQF)) { + /* + * We need to determine if it was one of the standard + * events: PF, AF, or UF. If so, we handle them and + * update the RTC core. + */ + if (likely(ctrlc & RTC_CTRL_B_PAU_MASK)) { + events = RTC_IRQF; + + /* Check for a periodic interrupt. */ + if ((ctrlb & RTC_CTRL_B_PIE) && + (ctrlc & RTC_CTRL_C_PF)) { + events |= RTC_PF; + num_irqs++; + } + + /* Check for an alarm interrupt. */ + if ((ctrlb & RTC_CTRL_B_AIE) && + (ctrlc & RTC_CTRL_C_AF)) { + events |= RTC_AF; + num_irqs++; + } + + /* Check for an update interrupt. */ + if ((ctrlb & RTC_CTRL_B_UIE) && + (ctrlc & RTC_CTRL_C_UF)) { + events |= RTC_UF; + num_irqs++; + } + + rtc_update_irq(rtc->dev, num_irqs, events); + } else { + /* + * One of the "extended" interrupts was received that + * is not recognized by the RTC core. These need to + * be handled in task context as they can call other + * functions and the time spent in irq context needs + * to be minimized. Schedule them into a workqueue + * and inform the RTC core that the IRQs were handled. + */ + spin_unlock(&rtc->lock); + schedule_work(&rtc->work); + rtc_update_irq(rtc->dev, 0, 0); + return IRQ_HANDLED; + } + } + spin_unlock(&rtc->lock); + + return events ? IRQ_HANDLED : IRQ_NONE; +} + +/** + * ds1685_rtc_work_queue - work queue handler. + * @work: work_struct containing data to work on in task context. + */ +static void +ds1685_rtc_work_queue(struct work_struct *work) +{ + struct ds1685_priv *rtc = container_of(work, + struct ds1685_priv, work); + struct platform_device *pdev = to_platform_device(&rtc->dev->dev); + struct mutex *rtc_mutex = &rtc->dev->ops_lock; + u8 ctrl4a, ctrl4b; + + mutex_lock(rtc_mutex); + + ds1685_rtc_switch_to_bank1(rtc); + ctrl4a = rtc->read(rtc, RTC_EXT_CTRL_4A); + ctrl4b = rtc->read(rtc, RTC_EXT_CTRL_4B); + + /* + * Check for a kickstart interrupt. With Vcc applied, this + * typically means that the power button was pressed, so we + * begin the shutdown sequence. + */ + if ((ctrl4b & RTC_CTRL_4B_KSE) && (ctrl4a & RTC_CTRL_4A_KF)) { + /* Briefly disable kickstarts to debounce button presses. */ + rtc->write(rtc, RTC_EXT_CTRL_4B, + (rtc->read(rtc, RTC_EXT_CTRL_4B) & + ~(RTC_CTRL_4B_KSE))); + + /* Clear the kickstart flag. */ + rtc->write(rtc, RTC_EXT_CTRL_4A, + (ctrl4a & ~(RTC_CTRL_4A_KF))); + + + /* + * Sleep 500ms before re-enabling kickstarts. This allows + * adequate time to avoid reading signal jitter as additional + * button presses. + */ + msleep(500); + rtc->write(rtc, RTC_EXT_CTRL_4B, + (rtc->read(rtc, RTC_EXT_CTRL_4B) | + RTC_CTRL_4B_KSE)); + + /* Call the platform pre-poweroff function. Else, shutdown. */ + if (rtc->prepare_poweroff != NULL) + rtc->prepare_poweroff(); + else + ds1685_rtc_poweroff(pdev); + } + + /* + * Check for a wake-up interrupt. With Vcc applied, this is + * essentially a second alarm interrupt, except it takes into + * account the 'date' register in bank1 in addition to the + * standard three alarm registers. + */ + if ((ctrl4b & RTC_CTRL_4B_WIE) && (ctrl4a & RTC_CTRL_4A_WF)) { + rtc->write(rtc, RTC_EXT_CTRL_4A, + (ctrl4a & ~(RTC_CTRL_4A_WF))); + + /* Call the platform wake_alarm function if defined. */ + if (rtc->wake_alarm != NULL) + rtc->wake_alarm(); + else + dev_warn(&pdev->dev, + "Wake Alarm IRQ just occurred!\n"); + } + + /* + * Check for a ram-clear interrupt. This happens if RIE=1 and RF=0 + * when RCE=1 in 4B. This clears all NVRAM bytes in bank0 by setting + * each byte to a logic 1. This has no effect on any extended + * NV-SRAM that might be present, nor on the time/calendar/alarm + * registers. After a ram-clear is completed, there is a minimum + * recovery time of ~150ms in which all reads/writes are locked out. + * NOTE: A ram-clear can still occur if RCE=1 and RIE=0. We cannot + * catch this scenario. + */ + if ((ctrl4b & RTC_CTRL_4B_RIE) && (ctrl4a & RTC_CTRL_4A_RF)) { + rtc->write(rtc, RTC_EXT_CTRL_4A, + (ctrl4a & ~(RTC_CTRL_4A_RF))); + msleep(150); + + /* Call the platform post_ram_clear function if defined. */ + if (rtc->post_ram_clear != NULL) + rtc->post_ram_clear(); + else + dev_warn(&pdev->dev, + "RAM-Clear IRQ just occurred!\n"); + } + ds1685_rtc_switch_to_bank0(rtc); + + mutex_unlock(rtc_mutex); +} +/* ----------------------------------------------------------------------- */ + + +/* ----------------------------------------------------------------------- */ +/* ProcFS interface */ + +#ifdef CONFIG_PROC_FS +#define NUM_REGS 6 /* Num of control registers. */ +#define NUM_BITS 8 /* Num bits per register. */ +#define NUM_SPACES 4 /* Num spaces between each bit. */ + +/* + * Periodic Interrupt Rates. + */ +static const char *ds1685_rtc_pirq_rate[16] = { + "none", "3.90625ms", "7.8125ms", "0.122070ms", "0.244141ms", + "0.488281ms", "0.9765625ms", "1.953125ms", "3.90625ms", "7.8125ms", + "15.625ms", "31.25ms", "62.5ms", "125ms", "250ms", "500ms" +}; + +/* + * Square-Wave Output Frequencies. + */ +static const char *ds1685_rtc_sqw_freq[16] = { + "none", "256Hz", "128Hz", "8192Hz", "4096Hz", "2048Hz", "1024Hz", + "512Hz", "256Hz", "128Hz", "64Hz", "32Hz", "16Hz", "8Hz", "4Hz", "2Hz" +}; + +#ifdef CONFIG_RTC_DS1685_PROC_REGS +/** + * ds1685_rtc_print_regs - helper function to print register values. + * @hex: hex byte to convert into binary bits. + * @dest: destination char array. + * + * This is basically a hex->binary function, just with extra spacing between + * the digits. It only works on 1-byte values (8 bits). + */ +static char* +ds1685_rtc_print_regs(u8 hex, char *dest) +{ + u32 i, j; + char *tmp = dest; + + for (i = 0; i < NUM_BITS; i++) { + *tmp++ = ((hex & 0x80) != 0 ? '1' : '0'); + for (j = 0; j < NUM_SPACES; j++) + *tmp++ = ' '; + hex <<= 1; + } + *tmp++ = '\0'; + + return dest; +} +#endif + +/** + * ds1685_rtc_proc - procfs access function. + * @dev: pointer to device structure. + * @seq: pointer to seq_file structure. + */ +static int +ds1685_rtc_proc(struct device *dev, struct seq_file *seq) +{ + struct platform_device *pdev = to_platform_device(dev); + struct ds1685_priv *rtc = platform_get_drvdata(pdev); + u8 ctrla, ctrlb, ctrlc, ctrld, ctrl4a, ctrl4b, ssn[8]; + char *model = '\0'; +#ifdef CONFIG_RTC_DS1685_PROC_REGS + char bits[NUM_REGS][(NUM_BITS * NUM_SPACES) + NUM_BITS + 1]; +#endif + + /* Read all the relevant data from the control registers. */ + ds1685_rtc_switch_to_bank1(rtc); + ds1685_rtc_get_ssn(rtc, ssn); + ctrla = rtc->read(rtc, RTC_CTRL_A); + ctrlb = rtc->read(rtc, RTC_CTRL_B); + ctrlc = rtc->read(rtc, RTC_CTRL_C); + ctrld = rtc->read(rtc, RTC_CTRL_D); + ctrl4a = rtc->read(rtc, RTC_EXT_CTRL_4A); + ctrl4b = rtc->read(rtc, RTC_EXT_CTRL_4B); + ds1685_rtc_switch_to_bank0(rtc); + + /* Determine the RTC model. */ + switch (ssn[0]) { + case RTC_MODEL_DS1685: + model = "DS1685/DS1687\0"; + break; + case RTC_MODEL_DS1689: + model = "DS1689/DS1693\0"; + break; + case RTC_MODEL_DS17285: + model = "DS17285/DS17287\0"; + break; + case RTC_MODEL_DS17485: + model = "DS17485/DS17487\0"; + break; + case RTC_MODEL_DS17885: + model = "DS17885/DS17887\0"; + break; + default: + model = "Unknown\0"; + break; + } + + /* Print out the information. */ + seq_printf(seq, + "Model\t\t: %s\n" + "Oscillator\t: %s\n" + "12/24hr\t\t: %s\n" + "DST\t\t: %s\n" + "Data mode\t: %s\n" + "Battery\t\t: %s\n" + "Aux batt\t: %s\n" + "Update IRQ\t: %s\n" + "Periodic IRQ\t: %s\n" + "Periodic Rate\t: %s\n" + "SQW Freq\t: %s\n" +#ifdef CONFIG_RTC_DS1685_PROC_REGS + "Serial #\t: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n" + "Register Status\t:\n" + " Ctrl A\t: UIP DV2 DV1 DV0 RS3 RS2 RS1 RS0\n" + "\t\t: %s\n" + " Ctrl B\t: SET PIE AIE UIE SQWE DM 2412 DSE\n" + "\t\t: %s\n" + " Ctrl C\t: IRQF PF AF UF --- --- --- ---\n" + "\t\t: %s\n" + " Ctrl D\t: VRT --- --- --- --- --- --- ---\n" + "\t\t: %s\n" +#if !defined(CONFIG_RTC_DRV_DS1685) && !defined(CONFIG_RTC_DRV_DS1689) + " Ctrl 4A\t: VRT2 INCR BME --- PAB RF WF KF\n" +#else + " Ctrl 4A\t: VRT2 INCR --- --- PAB RF WF KF\n" +#endif + "\t\t: %s\n" + " Ctrl 4B\t: ABE E32k CS RCE PRS RIE WIE KSE\n" + "\t\t: %s\n", +#else + "Serial #\t: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n", +#endif + model, + ((ctrla & RTC_CTRL_A_DV1) ? "enabled" : "disabled"), + ((ctrlb & RTC_CTRL_B_2412) ? "24-hour" : "12-hour"), + ((ctrlb & RTC_CTRL_B_DSE) ? "enabled" : "disabled"), + ((ctrlb & RTC_CTRL_B_DM) ? "binary" : "BCD"), + ((ctrld & RTC_CTRL_D_VRT) ? "ok" : "exhausted or n/a"), + ((ctrl4a & RTC_CTRL_4A_VRT2) ? "ok" : "exhausted or n/a"), + ((ctrlb & RTC_CTRL_B_UIE) ? "yes" : "no"), + ((ctrlb & RTC_CTRL_B_PIE) ? "yes" : "no"), + (!(ctrl4b & RTC_CTRL_4B_E32K) ? + ds1685_rtc_pirq_rate[(ctrla & RTC_CTRL_A_RS_MASK)] : "none"), + (!((ctrl4b & RTC_CTRL_4B_E32K)) ? + ds1685_rtc_sqw_freq[(ctrla & RTC_CTRL_A_RS_MASK)] : "32768Hz"), +#ifdef CONFIG_RTC_DS1685_PROC_REGS + ssn[0], ssn[1], ssn[2], ssn[3], ssn[4], ssn[5], ssn[6], ssn[7], + ds1685_rtc_print_regs(ctrla, bits[0]), + ds1685_rtc_print_regs(ctrlb, bits[1]), + ds1685_rtc_print_regs(ctrlc, bits[2]), + ds1685_rtc_print_regs(ctrld, bits[3]), + ds1685_rtc_print_regs(ctrl4a, bits[4]), + ds1685_rtc_print_regs(ctrl4b, bits[5])); +#else + ssn[0], ssn[1], ssn[2], ssn[3], ssn[4], ssn[5], ssn[6], ssn[7]); +#endif + return 0; +} +#else +#define ds1685_rtc_proc NULL +#endif /* CONFIG_PROC_FS */ +/* ----------------------------------------------------------------------- */ + + +/* ----------------------------------------------------------------------- */ +/* RTC Class operations */ + +static const struct rtc_class_ops +ds1685_rtc_ops = { + .proc = ds1685_rtc_proc, + .read_time = ds1685_rtc_read_time, + .set_time = ds1685_rtc_set_time, + .read_alarm = ds1685_rtc_read_alarm, + .set_alarm = ds1685_rtc_set_alarm, + .alarm_irq_enable = ds1685_rtc_alarm_irq_enable, +}; +/* ----------------------------------------------------------------------- */ |