diff options
Diffstat (limited to 'drivers/rtc')
| -rw-r--r-- | drivers/rtc/rtc-sa1100.c | 98 |
1 files changed, 74 insertions, 24 deletions
diff --git a/drivers/rtc/rtc-sa1100.c b/drivers/rtc/rtc-sa1100.c index b0985f727078..88ea52b8647a 100644 --- a/drivers/rtc/rtc-sa1100.c +++ b/drivers/rtc/rtc-sa1100.c @@ -42,7 +42,7 @@ #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); @@ -156,8 +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); @@ -175,7 +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; } @@ -183,8 +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; @@ -207,6 +263,7 @@ 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); @@ -226,6 +283,9 @@ static int sa1100_rtc_open(struct device *dev) 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: @@ -274,25 +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; } @@ -344,12 +385,14 @@ 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; @@ -365,6 +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) @@ -391,13 +436,18 @@ 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(). * |