Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 25 Jul 2002 13:30:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 25 Jul 2002 13:30:32 -0400 Received: from cpe-24-221-152-185.az.sprintbbd.net ([24.221.152.185]:64899 "EHLO opus.bloom.county") by vger.kernel.org with ESMTP id ; Thu, 25 Jul 2002 13:30:25 -0400 Date: Thu, 25 Jul 2002 10:33:37 -0700 From: Tom Rini To: Linus Torvalds Cc: Kernel Mailing List Subject: [PATCH] A generic RTC driver [3/3] Message-ID: <20020725173337.GF746@opus.bloom.county> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8255 Lines: 300 This is part 3 of 3 of the genrtc patches. This is my own slight bit of work. This changes set_rtc_time(struct *rtc_time) to return an int instead of void. This was done so that the arch-specific code here could do additional checks on the time and return an error if needed. This then introduces include/asm-generic/rtc.h, include/asm-i386/rtc.h and include/asm-alpha/rtc.h. include/asm-generic/rtc.h contains the get_rtc_time and set_rtc_time logic that is in drivers/char/rtc.c, slightly modified to not duplicate the tests done by the genrtc code but keeping the additional ones (years > 255 and > 169, as well as the CONFIG_DECSTATION ones). This portion has been tested on SMP i386. This also modifies include/asm-ppc/rtc.h to return -EINVAL if no rtc hardware is present (it would silently fail previously). -- Tom Rini (TR1265) http://gate.crashing.org/~trini/ --- linux-2.5/drivers/char/genrtc.c-original 2002-07-24 12:23:40.000000000 -0700 +++ linux-2.5/drivers/char/genrtc.c 2002-07-24 13:22:05.000000000 -0700 @@ -33,9 +33,10 @@ * 1.03 make it more portable zippel@linux-m68k.org * 1.04 removed useless timer code rz@linux-m68k.org * 1.05 portable RTC_UIE emulation rz@linux-m68k.org + * 1.06 set_rtc_time can return an error trini@kernel.crashing.org */ -#define RTC_VERSION "1.05" +#define RTC_VERSION "1.06" #include #include @@ -326,8 +327,7 @@ wtime.tm_sec < 0 || wtime.tm_sec >= 60) return -EINVAL; - set_rtc_time(&wtime); - return 0; + return set_rtc_time(&wtime); } } --- linux-2.5/include/asm-ppc/rtc.h-original 2002-07-24 13:25:15.000000000 -0700 +++ linux-2.5/include/asm-ppc/rtc.h 2002-07-24 13:25:36.000000000 -0700 @@ -68,7 +68,10 @@ time->tm_sec); (ppc_md.set_rtc_time)(nowtime); - } + + return 0; + } else + return -EINVAL; } static inline unsigned int get_rtc_ss(void) --- /dev/null 1969-12-31 17:00:00.000000000 -0700 +++ linux-2.5/include/asm-generic/rtc.h 2002-07-24 11:06:48.000000000 -0700 @@ -0,0 +1,211 @@ +/* + * inclue/asm-generic/rtc.h + * + * Author: Tom Rini + * + * Based on: + * drivers/char/rtc.c + * + * Please read the COPYING file for all license details. + */ + +#ifndef __ASM_RTC_H__ +#define __ASM_RTC_H__ + +#ifdef __KERNEL__ + +#include +#include + +#define RTC_PIE 0x40 /* periodic interrupt enable */ +#define RTC_AIE 0x20 /* alarm interrupt enable */ +#define RTC_UIE 0x10 /* update-finished interrupt enable */ + +extern void gen_rtc_interrupt(unsigned long); + +/* some dummy definitions */ +#define RTC_SQWE 0x08 /* enable square-wave output */ +#define RTC_DM_BINARY 0x04 /* all time/date values are BCD if clear */ +#define RTC_24H 0x02 /* 24 hour mode - else hours bit 7 means pm */ +#define RTC_DST_EN 0x01 /* auto switch DST - works f. USA only */ + +/* + * Returns true if a clock update is in progress + */ +static inline unsigned char rtc_is_updating(void) +{ + unsigned char uip; + + spin_lock_irq(&rtc_lock); + uip = (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP); + spin_unlock_irq(&rtc_lock); + return uip; +} + +static inline void get_rtc_time(struct rtc_time *time) +{ + unsigned long uip_watchdog = jiffies; + unsigned char ctrl; +#ifdef CONFIG_DECSTATION + unsigned int real_year; +#endif + + /* + * read RTC once any update in progress is done. The update + * can take just over 2ms. We wait 10 to 20ms. There is no need to + * to poll-wait (up to 1s - eeccch) for the falling edge of RTC_UIP. + * If you need to know *exactly* when a second has started, enable + * periodic update complete interrupts, (via ioctl) and then + * immediately read /dev/rtc which will block until you get the IRQ. + * Once the read clears, read the RTC time (again via ioctl). Easy. + */ + + if (rtc_is_updating() != 0) + while (jiffies - uip_watchdog < 2*HZ/100) { + barrier(); + cpu_relax(); + } + + /* + * Only the values that we read from the RTC are set. We leave + * tm_wday, tm_yday and tm_isdst untouched. Even though the + * RTC has RTC_DAY_OF_WEEK, we ignore it, as it is only updated + * by the RTC when initially set to a non-zero value. + */ + spin_lock_irq(&rtc_lock); + time->tm_sec = CMOS_READ(RTC_SECONDS); + time->tm_min = CMOS_READ(RTC_MINUTES); + time->tm_hour = CMOS_READ(RTC_HOURS); + time->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH); + time->tm_mon = CMOS_READ(RTC_MONTH); + time->tm_year = CMOS_READ(RTC_YEAR); +#ifdef CONFIG_DECSTATION + real_year = CMOS_READ(RTC_DEC_YEAR); +#endif + ctrl = CMOS_READ(RTC_CONTROL); + spin_unlock_irq(&rtc_lock); + + if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD) + { + BCD_TO_BIN(time->tm_sec); + BCD_TO_BIN(time->tm_min); + BCD_TO_BIN(time->tm_hour); + BCD_TO_BIN(time->tm_mday); + BCD_TO_BIN(time->tm_mon); + BCD_TO_BIN(time->tm_year); + } + +#ifdef CONFIG_DECSTATION + time->tm_year += real_year - 72; +#endif + + /* + * Account for differences between how the RTC uses the values + * and how they are defined in a struct rtc_time; + */ + if (time->tm_year <= 69) + time->tm_year += 100; + + time->tm_mon--; +} + +/* Set the current date and time in the real time clock. */ +static inline int set_rtc_time(struct rtc_time *time) +{ + unsigned char mon, day, hrs, min, sec; + unsigned char save_control, save_freq_select; + unsigned int yrs; +#ifdef CONFIG_DECSTATION + unsigned int real_yrs, leap_yr; +#endif + + yrs = time->tm_year; + mon = time->tm_mon + 1; /* tm_mon starts at zero */ + day = time->tm_mday; + hrs = time->tm_hour; + min = time->tm_min; + sec = time->tm_sec; + + if (yrs > 255) /* They are unsigned */ + return -EINVAL; + + spin_lock_irq(&rtc_lock); +#ifdef CONFIG_DECSTATION + real_yrs = yrs; + leap_yr = ((!((yrs + 1900) % 4) && ((yrs + 1900) % 100)) || + !((yrs + 1900) % 400)); + yrs = 72; + + /* + * We want to keep the year set to 73 until March + * for non-leap years, so that Feb, 29th is handled + * correctly. + */ + if (!leap_yr && mon < 3) { + real_yrs--; + yrs = 73; + } +#endif + /* These limits and adjustments are independant of + * whether the chip is in binary mode or not. + */ + if (yrs > 169) { + spin_unlock_irq(&rtc_lock); + return -EINVAL; + } + + if (yrs >= 100) + yrs -= 100; + + if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) + || RTC_ALWAYS_BCD) { + BIN_TO_BCD(sec); + BIN_TO_BCD(min); + BIN_TO_BCD(hrs); + BIN_TO_BCD(day); + BIN_TO_BCD(mon); + BIN_TO_BCD(yrs); + } + + save_control = CMOS_READ(RTC_CONTROL); + CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL); + save_freq_select = CMOS_READ(RTC_FREQ_SELECT); + CMOS_WRITE((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT); + +#ifdef CONFIG_DECSTATION + CMOS_WRITE(real_yrs, RTC_DEC_YEAR); +#endif + CMOS_WRITE(yrs, RTC_YEAR); + CMOS_WRITE(mon, RTC_MONTH); + CMOS_WRITE(day, RTC_DAY_OF_MONTH); + CMOS_WRITE(hrs, RTC_HOURS); + CMOS_WRITE(min, RTC_MINUTES); + CMOS_WRITE(sec, RTC_SECONDS); + + CMOS_WRITE(save_control, RTC_CONTROL); + CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT); + + spin_unlock_irq(&rtc_lock); + + return 0; +} + +static inline unsigned int get_rtc_ss(void) +{ + struct rtc_time h; + + get_rtc_time(&h); + return h.tm_sec; +} + +static inline int get_rtc_pll(struct rtc_pll_info *pll) +{ + return -EINVAL; +} +static inline int set_rtc_pll(struct rtc_pll_info *pll) +{ + return -EINVAL; +} + +#endif /* __KERNEL__ */ +#endif /* __ASM_RTC_H__ */ --- /dev/null 1969-12-31 17:00:00.000000000 -0700 +++ linux-2.5/include/asm-i386/rtc.h 2002-07-23 10:38:32.000000000 -0700 @@ -0,0 +1,10 @@ +#ifndef _I386_RTC_H +#define _I386_RTC_H + +/* + * x86 uses the default access methods for the RTC. + */ + +#include + +#endif --- /dev/null 1969-12-31 17:00:00.000000000 -0700 +++ linux-2.5/include/asm-alpha/rtc.h 2002-07-23 10:38:32.000000000 -0700 @@ -0,0 +1,10 @@ +#ifndef _ALPHA_RTC_H +#define _ALPHA_RTC_H + +/* + * Alpha uses the default access methods for the RTC. + */ + +#include + +#endif - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/