diff options
Diffstat (limited to 'drivers/rtc')
| -rw-r--r-- | drivers/rtc/Kconfig | 12 | ||||
| -rw-r--r-- | drivers/rtc/Makefile | 1 | ||||
| -rw-r--r-- | drivers/rtc/rtc-mrst.c | 582 | ||||
| -rw-r--r-- | drivers/rtc/rtc-rs5c372.c | 2 | ||||
| -rw-r--r-- | drivers/rtc/rtc-sa1100.c | 161 |
5 files changed, 723 insertions, 35 deletions
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index 2883428d5ac..4941cade319 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -463,6 +463,18 @@ config RTC_DRV_CMOS This driver can also be built as a module. If so, the module will be called rtc-cmos. +config RTC_DRV_VRTC + tristate "Virtual RTC for Moorestown platforms" + depends on X86_MRST + default y if X86_MRST + + help + Say "yes" here to get direct support for the real time clock + found on Moorestown platforms. The VRTC is a emulated RTC that + derives its clock source from a real RTC in the PMIC. The MC146818 + style programming interface is mostly conserved, but any + updates are done via IPC calls to the system controller FW. + config RTC_DRV_DS1216 tristate "Dallas DS1216" depends on SNI_RM diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index 4c2832df469..2afdaf3ff98 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -30,6 +30,7 @@ obj-$(CONFIG_RTC_DRV_CMOS) += rtc-cmos.o obj-$(CONFIG_RTC_DRV_COH901331) += rtc-coh901331.o obj-$(CONFIG_RTC_DRV_DAVINCI) += rtc-davinci.o obj-$(CONFIG_RTC_DRV_DM355EVM) += rtc-dm355evm.o +obj-$(CONFIG_RTC_DRV_VRTC) += rtc-mrst.o obj-$(CONFIG_RTC_DRV_DS1216) += rtc-ds1216.o obj-$(CONFIG_RTC_DRV_DS1286) += rtc-ds1286.o obj-$(CONFIG_RTC_DRV_DS1302) += rtc-ds1302.o diff --git a/drivers/rtc/rtc-mrst.c b/drivers/rtc/rtc-mrst.c new file mode 100644 index 00000000000..bcd0cf63eb1 --- /dev/null +++ b/drivers/rtc/rtc-mrst.c @@ -0,0 +1,582 @@ +/* + * rtc-mrst.c: Driver for Moorestown virtual RTC + * + * (C) Copyright 2009 Intel Corporation + * Author: Jacob Pan (jacob.jun.pan@intel.com) + * Feng Tang (feng.tang@intel.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; version 2 + * of the License. + * + * Note: + * VRTC is emulated by system controller firmware, the real HW + * RTC is located in the PMIC device. SCU FW shadows PMIC RTC + * in a memory mapped IO space that is visible to the host IA + * processor. + * + * This driver is based upon drivers/rtc/rtc-cmos.c + */ + +/* + * Note: + * * vRTC only supports binary mode and 24H mode + * * vRTC only support PIE and AIE, no UIE, and its PIE only happens + * at 23:59:59pm everyday, no support for adjustable frequency + * * Alarm function is also limited to hr/min/sec. + */ + +#include <linux/mod_devicetable.h> +#include <linux/platform_device.h> +#include <linux/interrupt.h> +#include <linux/spinlock.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/sfi.h> + +#include <asm-generic/rtc.h> +#include <asm/intel_scu_ipc.h> +#include <asm/mrst.h> +#include <asm/mrst-vrtc.h> + +struct mrst_rtc { + struct rtc_device *rtc; + struct device *dev; + int irq; + struct resource *iomem; + + u8 enabled_wake; + u8 suspend_ctrl; +}; + +static const char driver_name[] = "rtc_mrst"; + +#define RTC_IRQMASK (RTC_PF | RTC_AF) + +static inline int is_intr(u8 rtc_intr) +{ + if (!(rtc_intr & RTC_IRQF)) + return 0; + return rtc_intr & RTC_IRQMASK; +} + +/* + * rtc_time's year contains the increment over 1900, but vRTC's YEAR + * register can't be programmed to value larger than 0x64, so vRTC + * driver chose to use 1960 (1970 is UNIX time start point) as the base, + * and does the translation at read/write time. + * + * Why not just use 1970 as the offset? it's because using 1960 will + * make it consistent in leap year setting for both vrtc and low-level + * physical rtc devices. + */ +static int mrst_read_time(struct device *dev, struct rtc_time *time) +{ + unsigned long flags; + + if (rtc_is_updating()) + mdelay(20); + + spin_lock_irqsave(&rtc_lock, flags); + time->tm_sec = vrtc_cmos_read(RTC_SECONDS); + time->tm_min = vrtc_cmos_read(RTC_MINUTES); + time->tm_hour = vrtc_cmos_read(RTC_HOURS); + time->tm_mday = vrtc_cmos_read(RTC_DAY_OF_MONTH); + time->tm_mon = vrtc_cmos_read(RTC_MONTH); + time->tm_year = vrtc_cmos_read(RTC_YEAR); + spin_unlock_irqrestore(&rtc_lock, flags); + + /* Adjust for the 1960/1900 */ + time->tm_year += 60; + time->tm_mon--; + return RTC_24H; +} + +static int mrst_set_time(struct device *dev, struct rtc_time *time) +{ + int ret; + unsigned long flags; + unsigned char mon, day, hrs, min, sec; + unsigned int yrs; + + 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 < 70 || yrs > 138) + return -EINVAL; + yrs -= 60; + + spin_lock_irqsave(&rtc_lock, flags); + + vrtc_cmos_write(yrs, RTC_YEAR); + vrtc_cmos_write(mon, RTC_MONTH); + vrtc_cmos_write(day, RTC_DAY_OF_MONTH); + vrtc_cmos_write(hrs, RTC_HOURS); + vrtc_cmos_write(min, RTC_MINUTES); + vrtc_cmos_write(sec, RTC_SECONDS); + + spin_unlock_irqrestore(&rtc_lock, flags); + + ret = intel_scu_ipc_simple_command(IPCMSG_VRTC, IPC_CMD_VRTC_SETTIME); + return ret; +} + +static int mrst_read_alarm(struct device *dev, struct rtc_wkalrm *t) +{ + struct mrst_rtc *mrst = dev_get_drvdata(dev); + unsigned char rtc_control; + + if (mrst->irq <= 0) + return -EIO; + + /* Basic alarms only support hour, minute, and seconds fields. + * Some also support day and month, for alarms up to a year in + * the future. + */ + t->time.tm_mday = -1; + t->time.tm_mon = -1; + t->time.tm_year = -1; + + /* vRTC only supports binary mode */ + spin_lock_irq(&rtc_lock); + t->time.tm_sec = vrtc_cmos_read(RTC_SECONDS_ALARM); + t->time.tm_min = vrtc_cmos_read(RTC_MINUTES_ALARM); + t->time.tm_hour = vrtc_cmos_read(RTC_HOURS_ALARM); + + rtc_control = vrtc_cmos_read(RTC_CONTROL); + spin_unlock_irq(&rtc_lock); + + t->enabled = !!(rtc_control & RTC_AIE); + t->pending = 0; + + return 0; +} + +static void mrst_checkintr(struct mrst_rtc *mrst, unsigned char rtc_control) +{ + unsigned char rtc_intr; + + /* + * NOTE after changing RTC_xIE bits we always read INTR_FLAGS; + * allegedly some older rtcs need that to handle irqs properly + */ + rtc_intr = vrtc_cmos_read(RTC_INTR_FLAGS); + rtc_intr &= (rtc_control & RTC_IRQMASK) | RTC_IRQF; + if (is_intr(rtc_intr)) + rtc_update_irq(mrst->rtc, 1, rtc_intr); +} + +static void mrst_irq_enable(struct mrst_rtc *mrst, unsigned char mask) +{ + unsigned char rtc_control; + + /* + * Flush any pending IRQ status, notably for update irqs, + * before we enable new IRQs + */ + rtc_control = vrtc_cmos_read(RTC_CONTROL); + mrst_checkintr(mrst, rtc_control); + + rtc_control |= mask; + vrtc_cmos_write(rtc_control, RTC_CONTROL); + + mrst_checkintr(mrst, rtc_control); +} + +static void mrst_irq_disable(struct mrst_rtc *mrst, unsigned char mask) +{ + unsigned char rtc_control; + + rtc_control = vrtc_cmos_read(RTC_CONTROL); + rtc_control &= ~mask; + vrtc_cmos_write(rtc_control, RTC_CONTROL); + mrst_checkintr(mrst, rtc_control); +} + +static int mrst_set_alarm(struct device *dev, struct rtc_wkalrm *t) +{ + struct mrst_rtc *mrst = dev_get_drvdata(dev); + unsigned char hrs, min, sec; + int ret = 0; + + if (!mrst->irq) + return -EIO; + + hrs = t->time.tm_hour; + min = t->time.tm_min; + sec = t->time.tm_sec; + + spin_lock_irq(&rtc_lock); + /* Next rtc irq must not be from previous alarm setting */ + mrst_irq_disable(mrst, RTC_AIE); + + /* Update alarm */ + vrtc_cmos_write(hrs, RTC_HOURS_ALARM); + vrtc_cmos_write(min, RTC_MINUTES_ALARM); + vrtc_cmos_write(sec, RTC_SECONDS_ALARM); + + spin_unlock_irq(&rtc_lock); + + ret = intel_scu_ipc_simple_command(IPCMSG_VRTC, IPC_CMD_VRTC_SETALARM); + if (ret) + return ret; + + spin_lock_irq(&rtc_lock); + if (t->enabled) + mrst_irq_enable(mrst, RTC_AIE); + + spin_unlock_irq(&rtc_lock); + + return 0; +} + +static int mrst_irq_set_state(struct device *dev, int enabled) +{ + struct mrst_rtc *mrst = dev_get_drvdata(dev); + unsigned long flags; + + if (!mrst->irq) + return -ENXIO; + + spin_lock_irqsave(&rtc_lock, flags); + + if (enabled) + mrst_irq_enable(mrst, RTC_PIE); + else + mrst_irq_disable(mrst, RTC_PIE); + + spin_unlock_irqrestore(&rtc_lock, flags); + return 0; +} + +#if defined(CONFIG_RTC_INTF_DEV) || defined(CONFIG_RTC_INTF_DEV_MODULE) + +/* Currently, the vRTC doesn't support UIE ON/OFF */ +static int +mrst_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) +{ + struct mrst_rtc *mrst = dev_get_drvdata(dev); + unsigned long flags; + + switch (cmd) { + case RTC_AIE_OFF: + case RTC_AIE_ON: + if (!mrst->irq) + return -EINVAL; + break; + default: + /* PIE ON/OFF is handled by mrst_irq_set_state() */ + return -ENOIOCTLCMD; + } + + spin_lock_irqsave(&rtc_lock, flags); + switch (cmd) { + case RTC_AIE_OFF: /* alarm off */ + mrst_irq_disable(mrst, RTC_AIE); + break; + case RTC_AIE_ON: /* alarm on */ + mrst_irq_enable(mrst, RTC_AIE); + break; + } + spin_unlock_irqrestore(&rtc_lock, flags); + return 0; +} + +#else +#define mrst_rtc_ioctl NULL +#endif + +#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE) + +static int mrst_procfs(struct device *dev, struct seq_file *seq) +{ + unsigned char rtc_control, valid; + + spin_lock_irq(&rtc_lock); + rtc_control = vrtc_cmos_read(RTC_CONTROL); + valid = vrtc_cmos_read(RTC_VALID); + spin_unlock_irq(&rtc_lock); + + return seq_printf(seq, + "periodic_IRQ\t: %s\n" + "alarm\t\t: %s\n" + "BCD\t\t: no\n" + "periodic_freq\t: daily (not adjustable)\n", + (rtc_control & RTC_PIE) ? "on" : "off", + (rtc_control & RTC_AIE) ? "on" : "off"); +} + +#else +#define mrst_procfs NULL +#endif + +static const struct rtc_class_ops mrst_rtc_ops = { + .ioctl = mrst_rtc_ioctl, + .read_time = mrst_read_time, + .set_time = mrst_set_time, + .read_alarm = mrst_read_alarm, + .set_alarm = mrst_set_alarm, + .proc = mrst_procfs, + .irq_set_state = mrst_irq_set_state, +}; + +static struct mrst_rtc mrst_rtc; + +/* + * When vRTC IRQ is captured by SCU FW, FW will clear the AIE bit in + * Reg B, so no need for this driver to clear it + */ +static irqreturn_t mrst_rtc_irq(int irq, void *p) +{ + u8 irqstat; + + spin_lock(&rtc_lock); + /* This read will clear all IRQ flags inside Reg C */ + irqstat = vrtc_cmos_read(RTC_INTR_FLAGS); + spin_unlock(&rtc_lock); + + irqstat &= RTC_IRQMASK | RTC_IRQF; + if (is_intr(irqstat)) { + rtc_update_irq(p, 1, irqstat); + return IRQ_HANDLED; + } + return IRQ_NONE; +} + +static int __init +vrtc_mrst_do_probe(struct device *dev, struct resource *iomem, int rtc_irq) +{ + int retval = 0; + unsigned char rtc_control; + + /* There can be only one ... */ + if (mrst_rtc.dev) + return -EBUSY; + + if (!iomem) + return -ENODEV; + + iomem = request_mem_region(iomem->start, + iomem->end + 1 - iomem->start, + driver_name); + if (!iomem) { + dev_dbg(dev, "i/o mem already in use.\n"); + return -EBUSY; + } + + mrst_rtc.irq = rtc_irq; + mrst_rtc.iomem = iomem; + + mrst_rtc.rtc = rtc_device_register(driver_name, dev, + &mrst_rtc_ops, THIS_MODULE); + if (IS_ERR(mrst_rtc.rtc)) { + retval = PTR_ERR(mrst_rtc.rtc); + goto cleanup0; + } + + mrst_rtc.dev = dev; + dev_set_drvdata(dev, &mrst_rtc); + rename_region(iomem, dev_name(&mrst_rtc.rtc->dev)); + + spin_lock_irq(&rtc_lock); + mrst_irq_disable(&mrst_rtc, RTC_PIE | RTC_AIE); + rtc_control = vrtc_cmos_read(RTC_CONTROL); + spin_unlock_irq(&rtc_lock); + + if (!(rtc_control & RTC_24H) || (rtc_control & (RTC_DM_BINARY))) + dev_dbg(dev, "TODO: support more than 24-hr BCD mode\n"); + + if (rtc_irq) { + retval = request_irq(rtc_irq, mrst_rtc_irq, + IRQF_DISABLED, dev_name(&mrst_rtc.rtc->dev), + mrst_rtc.rtc); + if (retval < 0) { + dev_dbg(dev, "IRQ %d is already in use, err %d\n", + rtc_irq, retval); + goto cleanup1; + } + } + dev_dbg(dev, "initialised\n"); + return 0; + +cleanup1: + mrst_rtc.dev = NULL; + rtc_device_unregister(mrst_rtc.rtc); +cleanup0: + release_region(iomem->start, iomem->end + 1 - iomem->start); + dev_err(dev, "rtc-mrst: unable to initialise\n"); + return retval; +} + +static void rtc_mrst_do_shutdown(void) +{ + spin_lock_irq(&rtc_lock); + mrst_irq_disable(&mrst_rtc, RTC_IRQMASK); + spin_unlock_irq(&rtc_lock); +} + +static void __exit rtc_mrst_do_remove(struct device *dev) +{ + struct mrst_rtc *mrst = dev_get_drvdata(dev); + struct resource *iomem; + + rtc_mrst_do_shutdown(); + + if (mrst->irq) + free_irq(mrst->irq, mrst->rtc); + + rtc_device_unregister(mrst->rtc); + mrst->rtc = NULL; + + iomem = mrst->iomem; + release_region(iomem->start, iomem->end + 1 - iomem->start); + mrst->iomem = NULL; + + mrst->dev = NULL; + dev_set_drvdata(dev, NULL); +} + +#ifdef CONFIG_PM +static int mrst_suspend(struct device *dev, pm_message_t mesg) +{ + struct mrst_rtc *mrst = dev_get_drvdata(dev); + unsigned char tmp; + + /* Only the alarm might be a wakeup event source */ + spin_lock_irq(&rtc_lock); + mrst->suspend_ctrl = tmp = vrtc_cmos_read(RTC_CONTROL); + if (tmp & (RTC_PIE | RTC_AIE)) { + unsigned char mask; + + if (device_may_wakeup(dev)) + mask = RTC_IRQMASK & ~RTC_AIE; + else + mask = RTC_IRQMASK; + tmp &= ~mask; + vrtc_cmos_write(tmp, RTC_CONTROL); + + mrst_checkintr(mrst, tmp); + } + spin_unlock_irq(&rtc_lock); + + if (tmp & RTC_AIE) { + mrst->enabled_wake = 1; + enable_irq_wake(mrst->irq); + } + + dev_dbg(&mrst_rtc.rtc->dev, "suspend%s, ctrl %02x\n", + (tmp & RTC_AIE) ? ", alarm may wake" : "", + tmp); + + return 0; +} + +/* + * We want RTC alarms to wake us from the deep power saving state + */ +static inline int mrst_poweroff(struct device *dev) +{ + return mrst_suspend(dev, PMSG_HIBERNATE); +} + +static int mrst_resume(struct device *dev) +{ + struct mrst_rtc *mrst = dev_get_drvdata(dev); + unsigned char tmp = mrst->suspend_ctrl; + + /* Re-enable any irqs previously active */ + if (tmp & RTC_IRQMASK) { + unsigned char mask; + + if (mrst->enabled_wake) { + disable_irq_wake(mrst->irq); + mrst->enabled_wake = 0; + } + + spin_lock_irq(&rtc_lock); + do { + vrtc_cmos_write(tmp, RTC_CONTROL); + + mask = vrtc_cmos_read(RTC_INTR_FLAGS); + mask &= (tmp & RTC_IRQMASK) | RTC_IRQF; + if (!is_intr(mask)) + break; + + rtc_update_irq(mrst->rtc, 1, mask); + tmp &= ~RTC_AIE; + } while (mask & RTC_AIE); + spin_unlock_irq(&rtc_lock); + } + + dev_dbg(&mrst_rtc.rtc->dev, "resume, ctrl %02x\n", tmp); + + return 0; +} + +#else +#define mrst_suspend NULL +#define mrst_resume NULL + +static inline int mrst_poweroff(struct device *dev) +{ + return -ENOSYS; +} + +#endif + +static int __init vrtc_mrst_platform_probe(struct platform_device *pdev) +{ + return vrtc_mrst_do_probe(&pdev->dev, + platform_get_resource(pdev, IORESOURCE_MEM, 0), + platform_get_irq(pdev, 0)); +} + +static int __exit vrtc_mrst_platform_remove(struct platform_device *pdev) +{ + rtc_mrst_do_remove(&pdev->dev); + return 0; +} + +static void vrtc_mrst_platform_shutdown(struct platform_device *pdev) +{ + if (system_state == SYSTEM_POWER_OFF && !mrst_poweroff(&pdev->dev)) + return; + + rtc_mrst_do_shutdown(); +} + +MODULE_ALIAS("platform:vrtc_mrst"); + +static struct platform_driver vrtc_mrst_platform_driver = { + .probe = vrtc_mrst_platform_probe, + .remove = __exit_p(vrtc_mrst_platform_remove), + .shutdown = vrtc_mrst_platform_shutdown, + .driver = { + .name = (char *) driver_name, + .suspend = mrst_suspend, + .resume = mrst_resume, + } +}; + +static int __init vrtc_mrst_init(void) +{ + return platform_driver_register(&vrtc_mrst_platform_driver); +} + +static void __exit vrtc_mrst_exit(void) +{ + platform_driver_unregister(&vrtc_mrst_platform_driver); +} + +module_init(vrtc_mrst_init); +module_exit(vrtc_mrst_exit); + +MODULE_AUTHOR("Jacob Pan; Feng Tang"); +MODULE_DESCRIPTION("Driver for Moorestown virtual RTC"); +MODULE_LICENSE("GPL"); diff --git a/drivers/rtc/rtc-rs5c372.c b/drivers/rtc/rtc-rs5c372.c index 90cf0a6ff23..dd14e202c2c 100644 --- a/drivers/rtc/rtc-rs5c372.c +++ b/drivers/rtc/rtc-rs5c372.c @@ -207,7 +207,7 @@ static int rs5c372_get_datetime(struct i2c_client *client, struct rtc_time *tm) static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm) { struct rs5c372 *rs5c = i2c_get_clientdata(client); - unsigned char buf[8]; + unsigned char buf[7]; int addr; dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d " diff --git a/drivers/rtc/rtc-sa1100.c b/drivers/rtc/rtc-sa1100.c index e4a44b64170..88ea52b8647 100644 --- a/drivers/rtc/rtc-sa1100.c +++ b/drivers/rtc/rtc-sa1100.c @@ -39,10 +39,10 @@ #include <mach/regs-ost.h> #endif -#define RTC_DEF_DIVIDER 32768 - 1 +#define RTC_DEF_DIVIDER (32768 - 1) #define RTC_DEF_TRIM 0 -static unsigned long rtc_freq = 1024; +static const unsigned long RTC_FREQ = 1024; static unsigned long timer_freq; static struct rtc_time rtc_alarm; static DEFINE_SPINLOCK(sa1100_rtc_lock); @@ -61,7 +61,8 @@ static inline int rtc_periodic_alarm(struct rtc_time *tm) * Calculate the next alarm time given the requested alarm time mask * and the current time. */ -static void rtc_next_alarm_time(struct rtc_time *next, struct rtc_time *now, struct rtc_time *alrm) +static void rtc_next_alarm_time(struct rtc_time *next, struct rtc_time *now, + struct rtc_time *alrm) { unsigned long next_time; unsigned long now_time; @@ -116,7 +117,23 @@ static irqreturn_t sa1100_rtc_interrupt(int irq, void *dev_id) rtsr = RTSR; /* clear interrupt sources */ RTSR = 0; - RTSR = (RTSR_AL | RTSR_HZ) & (rtsr >> 2); + /* Fix for a nasty initialization problem the in SA11xx RTSR register. + * See also the comments in sa1100_rtc_probe(). */ + if (rtsr & (RTSR_ALE | RTSR_HZE)) { + /* This is the original code, before there was the if test + * above. This code does not clear interrupts that were not + * enabled. */ + RTSR = (RTSR_AL | RTSR_HZ) & (rtsr >> 2); + } else { + /* For some reason, it is possible to enter this routine + * without interruptions enabled, it has been tested with + * several units (Bug in SA11xx chip?). + * + * This situation leads to an infinite "loop" of interrupt + * routine calling and as a result the processor seems to + * lock on its first call to open(). */ + RTSR = RTSR_AL | RTSR_HZ; + } /* clear alarm interrupt if it has occurred */ if (rtsr & RTSR_AL) @@ -139,8 +156,58 @@ static irqreturn_t sa1100_rtc_interrupt(int irq, void *dev_id) return IRQ_HANDLED; } +static int sa1100_irq_set_freq(struct device *dev, int freq) +{ + if (freq < 1 || freq > timer_freq) { + return -EINVAL; + } else { + struct rtc_device *rtc = (struct rtc_device *)dev; + + rtc->irq_freq = freq; + + return 0; + } +} + static int rtc_timer1_count; +static int sa1100_irq_set_state(struct device *dev, int enabled) +{ + spin_lock_irq(&sa1100_rtc_lock); + if (enabled) { + struct rtc_device *rtc = (struct rtc_device *)dev; + + OSMR1 = timer_freq / rtc->irq_freq + OSCR; + OIER |= OIER_E1; + rtc_timer1_count = 1; + } else { + OIER &= ~OIER_E1; + } + spin_unlock_irq(&sa1100_rtc_lock); + + return 0; +} + +static inline int sa1100_timer1_retrigger(struct rtc_device *rtc) +{ + unsigned long diff; + unsigned long period = timer_freq / rtc->irq_freq; + + spin_lock_irq(&sa1100_rtc_lock); + + do { + OSMR1 += period; + diff = OSMR1 - OSCR; + /* If OSCR > OSMR1, diff is a very large number (unsigned + * math). This means we have a lost interrupt. */ + } while (diff > period); + OIER |= OIER_E1; + + spin_unlock_irq(&sa1100_rtc_lock); + + return 0; +} + static irqreturn_t timer1_interrupt(int irq, void *dev_id) { struct platform_device *pdev = to_platform_device(dev_id); @@ -158,7 +225,11 @@ static irqreturn_t timer1_interrupt(int irq, void *dev_id) rtc_update_irq(rtc, rtc_timer1_count, RTC_PF | RTC_IRQF); if (rtc_timer1_count == 1) - rtc_timer1_count = (rtc_freq * ((1 << 30) / (timer_freq >> 2))); + rtc_timer1_count = + (rtc->irq_freq * ((1 << 30) / (timer_freq >> 2))); + + /* retrigger. */ + sa1100_timer1_retrigger(rtc); return IRQ_HANDLED; } @@ -166,8 +237,10 @@ static irqreturn_t timer1_interrupt(int irq, void *dev_id) static int sa1100_rtc_read_callback(struct device *dev, int data) { if (data & RTC_PF) { + struct rtc_device *rtc = (struct rtc_device *)dev; + /* interpolate missed periods and set match for the next */ - unsigned long period = timer_freq / rtc_freq; + unsigned long period = timer_freq / rtc->irq_freq; unsigned long oscr = OSCR; unsigned long osmr1 = OSMR1; unsigned long missed = (oscr - osmr1)/period; @@ -178,7 +251,7 @@ static int sa1100_rtc_read_callback(struct device *dev, int data) * Here we compare (match - OSCR) 8 instead of 0 -- * see comment in pxa_timer_interrupt() for explanation. */ - while( (signed long)((osmr1 = OSMR1) - OSCR) <= 8 ) { + while ((signed long)((osmr1 = OSMR1) - OSCR) <= 8) { data += 0x100; OSSR = OSSR_M1; /* clear match on timer 1 */ OSMR1 = osmr1 + period; @@ -190,25 +263,29 @@ static int sa1100_rtc_read_callback(struct device *dev, int data) static int sa1100_rtc_open(struct device *dev) { int ret; + struct rtc_device *rtc = (struct rtc_device *)dev; ret = request_irq(IRQ_RTC1Hz, sa1100_rtc_interrupt, IRQF_DISABLED, - "rtc 1Hz", dev); + "rtc 1Hz", dev); if (ret) { dev_err(dev, "IRQ %d already in use.\n", IRQ_RTC1Hz); goto fail_ui; } ret = request_irq(IRQ_RTCAlrm, sa1100_rtc_interrupt, IRQF_DISABLED, - "rtc Alrm", dev); + "rtc Alrm", dev); if (ret) { dev_err(dev, "IRQ %d already in use.\n", IRQ_RTCAlrm); goto fail_ai; } ret = request_irq(IRQ_OST1, timer1_interrupt, IRQF_DISABLED, - "rtc timer", dev); + "rtc timer", dev); if (ret) { dev_err(dev, "IRQ %d already in use.\n", IRQ_OST1); goto fail_pi; } + rtc->max_user_freq = RTC_FREQ; + sa1100_irq_set_freq(dev, RTC_FREQ); + return 0; fail_pi: @@ -236,7 +313,7 @@ static void sa1100_rtc_release(struct device *dev) static int sa1100_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) { - switch(cmd) { + switch (cmd) { case RTC_AIE_OFF: spin_lock_irq(&sa1100_rtc_lock); RTSR &= ~RTSR_ALE; @@ -257,25 +334,6 @@ static int sa1100_rtc_ioctl(struct device *dev, unsigned int cmd, RTSR |= RTSR_HZE; spin_unlock_irq(&sa1100_rtc_lock); return 0; - case RTC_PIE_OFF: - spin_lock_irq(&sa1100_rtc_lock); - OIER &= ~OIER_E1; - spin_unlock_irq(&sa1100_rtc_lock); - return 0; - case RTC_PIE_ON: - spin_lock_irq(&sa1100_rtc_lock); - OSMR1 = timer_freq / rtc_freq + OSCR; - OIER |= OIER_E1; - rtc_timer1_count = 1; - spin_unlock_irq(&sa1100_rtc_lock); - return 0; - case RTC_IRQP_READ: - return put_user(rtc_freq, (unsigned long *)arg); - case RTC_IRQP_SET: - if (arg < 1 || arg > timer_freq) - return -EINVAL; - rtc_freq = arg; - return 0; } return -ENOIOCTLCMD; } @@ -327,12 +385,15 @@ static int sa1100_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) static int sa1100_rtc_proc(struct device *dev, struct seq_file *seq) { + struct rtc_device *rtc = (struct rtc_device *)dev; + seq_printf(seq, "trim/divider\t: 0x%08x\n", (u32) RTTR); seq_printf(seq, "update_IRQ\t: %s\n", (RTSR & RTSR_HZE) ? "yes" : "no"); seq_printf(seq, "periodic_IRQ\t: %s\n", (OIER & OIER_E1) ? "yes" : "no"); - seq_printf(seq, "periodic_freq\t: %ld\n", rtc_freq); + seq_printf(seq, "periodic_freq\t: %d\n", rtc->irq_freq); + seq_printf(seq, "RTSR\t\t: 0x%08x\n", (u32)RTSR); return 0; } @@ -347,6 +408,8 @@ static const struct rtc_class_ops sa1100_rtc_ops = { .read_alarm = sa1100_rtc_read_alarm, .set_alarm = sa1100_rtc_set_alarm, .proc = sa1100_rtc_proc, + .irq_set_freq = sa1100_irq_set_freq, + .irq_set_state = sa1100_irq_set_state, }; static int sa1100_rtc_probe(struct platform_device *pdev) @@ -364,7 +427,8 @@ static int sa1100_rtc_probe(struct platform_device *pdev) */ if (RTTR == 0) { RTTR = RTC_DEF_DIVIDER + (RTC_DEF_TRIM << 16); - dev_warn(&pdev->dev, "warning: initializing default clock divider/trim value\n"); + dev_warn(&pdev->dev, "warning: " + "initializing default clock divider/trim value\n"); /* The current RTC value probably doesn't make sense either */ RCNR = 0; } @@ -372,13 +436,42 @@ static int sa1100_rtc_probe(struct platform_device *pdev) device_init_wakeup(&pdev->dev, 1); rtc = rtc_device_register(pdev->name, &pdev->dev, &sa1100_rtc_ops, - THIS_MODULE); + THIS_MODULE); if (IS_ERR(rtc)) return PTR_ERR(rtc); platform_set_drvdata(pdev, rtc); + /* Set the irq_freq */ + /*TODO: Find out who is messing with this value after we initialize + * it here.*/ + rtc->irq_freq = RTC_FREQ; + + /* Fix for a nasty initialization problem the in SA11xx RTSR register. + * See also the comments in sa1100_rtc_interrupt(). + * + * Sometimes bit 1 of the RTSR (RTSR_HZ) will wake up 1, which means an + * interrupt pending, even though interrupts were never enabled. + * In this case, this bit it must be reset before enabling + * interruptions to avoid a nonexistent interrupt to occur. + * + * In principle, the same problem would apply to bit 0, although it has + * never been observed to happen. + * + * This issue is addressed both here and in sa1100_rtc_interrupt(). + * If the issue is not addressed here, in the times when the processor + * wakes up with the bit set there will be one spurious interrupt. + * + * The issue is also dealt with in sa1100_rtc_interrupt() to be on the + * safe side, once the condition that lead to this strange + * initialization is unknown and could in principle happen during + * normal processing. + * + * Notice that clearing bit 1 and 0 is accomplished by writting ONES to + * the corresponding bits in RTSR. */ + RTSR = RTSR_AL | RTSR_HZ; + return 0; } @@ -386,7 +479,7 @@ static int sa1100_rtc_remove(struct platform_device *pdev) { struct rtc_device *rtc = platform_get_drvdata(pdev); - if (rtc) + if (rtc) rtc_device_unregister(rtc); return 0; |