From e24b0bfa2f0446ffaad2661040be23668133aef8 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Fri, 5 Apr 2013 18:16:34 +0200 Subject: [PATCH] Revert "drivers/rtc/rtc-at91rm9200.c: use a variable for storing IMR" This reverts commit 0ef1594c017521ea89278e80fe3f80dafb17abde. This patch introduced a few races which cannot be easily fixed with a small follow-up patch. Furthermore, the SoC with the broken hardware register, which this patch intended to add support for, can only be used with device trees, which this driver currently does not support. [ Here is the discussion that led to this "revert" patch: https://lkml.org/lkml/2013/4/3/176 ] Cc: stable Signed-off-by: Johan Hovold Signed-off-by: Nicolas Ferre Signed-off-by: Linus Torvalds --- drivers/rtc/rtc-at91rm9200.c | 50 +++++++++++++++++--------------------------- drivers/rtc/rtc-at91rm9200.h | 1 + 2 files changed, 20 insertions(+), 31 deletions(-) diff --git a/drivers/rtc/rtc-at91rm9200.c b/drivers/rtc/rtc-at91rm9200.c index 0a9f27e..434ebc3 100644 --- a/drivers/rtc/rtc-at91rm9200.c +++ b/drivers/rtc/rtc-at91rm9200.c @@ -44,7 +44,6 @@ static DECLARE_COMPLETION(at91_rtc_updated); static unsigned int at91_alarm_year = AT91_RTC_EPOCH; static void __iomem *at91_rtc_regs; static int irq; -static u32 at91_rtc_imr; /* * Decode time/date into rtc_time structure @@ -109,11 +108,9 @@ static int at91_rtc_settime(struct device *dev, struct rtc_time *tm) cr = at91_rtc_read(AT91_RTC_CR); at91_rtc_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM); - at91_rtc_imr |= AT91_RTC_ACKUPD; at91_rtc_write(AT91_RTC_IER, AT91_RTC_ACKUPD); wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */ at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD); - at91_rtc_imr &= ~AT91_RTC_ACKUPD; at91_rtc_write(AT91_RTC_TIMR, bin2bcd(tm->tm_sec) << 0 @@ -145,7 +142,7 @@ static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm) tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); tm->tm_year = at91_alarm_year - 1900; - alrm->enabled = (at91_rtc_imr & AT91_RTC_ALARM) + alrm->enabled = (at91_rtc_read(AT91_RTC_IMR) & AT91_RTC_ALARM) ? 1 : 0; dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__, @@ -171,7 +168,6 @@ static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm) tm.tm_sec = alrm->time.tm_sec; at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM); - at91_rtc_imr &= ~AT91_RTC_ALARM; at91_rtc_write(AT91_RTC_TIMALR, bin2bcd(tm.tm_sec) << 0 | bin2bcd(tm.tm_min) << 8 @@ -184,7 +180,6 @@ static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm) if (alrm->enabled) { at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM); - at91_rtc_imr |= AT91_RTC_ALARM; at91_rtc_write(AT91_RTC_IER, AT91_RTC_ALARM); } @@ -201,12 +196,9 @@ static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) if (enabled) { at91_rtc_write(AT91_RTC_SCCR, AT91_RTC_ALARM); - at91_rtc_imr |= AT91_RTC_ALARM; at91_rtc_write(AT91_RTC_IER, AT91_RTC_ALARM); - } else { + } else at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM); - at91_rtc_imr &= ~AT91_RTC_ALARM; - } return 0; } @@ -215,10 +207,12 @@ static int at91_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) */ static int at91_rtc_proc(struct device *dev, struct seq_file *seq) { + unsigned long imr = at91_rtc_read(AT91_RTC_IMR); + seq_printf(seq, "update_IRQ\t: %s\n", - (at91_rtc_imr & AT91_RTC_ACKUPD) ? "yes" : "no"); + (imr & AT91_RTC_ACKUPD) ? "yes" : "no"); seq_printf(seq, "periodic_IRQ\t: %s\n", - (at91_rtc_imr & AT91_RTC_SECEV) ? "yes" : "no"); + (imr & AT91_RTC_SECEV) ? "yes" : "no"); return 0; } @@ -233,7 +227,7 @@ static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id) unsigned int rtsr; unsigned long events = 0; - rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_imr; + rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read(AT91_RTC_IMR); if (rtsr) { /* this interrupt is shared! Is it ours? */ if (rtsr & AT91_RTC_ALARM) events |= (RTC_AF | RTC_IRQF); @@ -297,7 +291,6 @@ static int __init at91_rtc_probe(struct platform_device *pdev) at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM | AT91_RTC_SECEV | AT91_RTC_TIMEV | AT91_RTC_CALEV); - at91_rtc_imr = 0; ret = request_irq(irq, at91_rtc_interrupt, IRQF_SHARED, @@ -336,7 +329,6 @@ static int __exit at91_rtc_remove(struct platform_device *pdev) at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM | AT91_RTC_SECEV | AT91_RTC_TIMEV | AT91_RTC_CALEV); - at91_rtc_imr = 0; free_irq(irq, pdev); rtc_device_unregister(rtc); @@ -349,35 +341,31 @@ static int __exit at91_rtc_remove(struct platform_device *pdev) /* AT91RM9200 RTC Power management control */ -static u32 at91_rtc_bkpimr; - +static u32 at91_rtc_imr; static int at91_rtc_suspend(struct device *dev) { /* this IRQ is shared with DBGU and other hardware which isn't * necessarily doing PM like we are... */ - at91_rtc_bkpimr = at91_rtc_imr & (AT91_RTC_ALARM|AT91_RTC_SECEV); - if (at91_rtc_bkpimr) { - if (device_may_wakeup(dev)) { + at91_rtc_imr = at91_rtc_read(AT91_RTC_IMR) + & (AT91_RTC_ALARM|AT91_RTC_SECEV); + if (at91_rtc_imr) { + if (device_may_wakeup(dev)) enable_irq_wake(irq); - } else { - at91_rtc_write(AT91_RTC_IDR, at91_rtc_bkpimr); - at91_rtc_imr &= ~at91_rtc_bkpimr; - } -} + else + at91_rtc_write(AT91_RTC_IDR, at91_rtc_imr); + } return 0; } static int at91_rtc_resume(struct device *dev) { - if (at91_rtc_bkpimr) { - if (device_may_wakeup(dev)) { + if (at91_rtc_imr) { + if (device_may_wakeup(dev)) disable_irq_wake(irq); - } else { - at91_rtc_imr |= at91_rtc_bkpimr; - at91_rtc_write(AT91_RTC_IER, at91_rtc_bkpimr); - } + else + at91_rtc_write(AT91_RTC_IER, at91_rtc_imr); } return 0; } diff --git a/drivers/rtc/rtc-at91rm9200.h b/drivers/rtc/rtc-at91rm9200.h index 5f940b6..da1945e 100644 --- a/drivers/rtc/rtc-at91rm9200.h +++ b/drivers/rtc/rtc-at91rm9200.h @@ -64,6 +64,7 @@ #define AT91_RTC_SCCR 0x1c /* Status Clear Command Register */ #define AT91_RTC_IER 0x20 /* Interrupt Enable Register */ #define AT91_RTC_IDR 0x24 /* Interrupt Disable Register */ +#define AT91_RTC_IMR 0x28 /* Interrupt Mask Register */ #define AT91_RTC_VER 0x2c /* Valid Entry Register */ #define AT91_RTC_NVTIM (1 << 0) /* Non valid Time */ -- 2.7.4