diff options
Diffstat (limited to 'drivers/rtc/rtc-bfin.c')
| -rw-r--r-- | drivers/rtc/rtc-bfin.c | 153 |
1 files changed, 77 insertions, 76 deletions
diff --git a/drivers/rtc/rtc-bfin.c b/drivers/rtc/rtc-bfin.c index 8624f55d0560..34439ce3967e 100644 --- a/drivers/rtc/rtc-bfin.c +++ b/drivers/rtc/rtc-bfin.c @@ -2,7 +2,7 @@ * Blackfin On-Chip Real Time Clock Driver * Supports BF52[257]/BF53[123]/BF53[467]/BF54[24789] * - * Copyright 2004-2007 Analog Devices Inc. + * Copyright 2004-2008 Analog Devices Inc. * * Enter bugs at http://blackfin.uclinux.org/ * @@ -32,6 +32,15 @@ * writes to clear status registers complete immediately. */ +/* It may seem odd that there is no SWCNT code in here (which would be exposed + * via the periodic interrupt event, or PIE). Since the Blackfin RTC peripheral + * runs in units of seconds (N/HZ) but the Linux framework runs in units of HZ + * (2^N HZ), there is no point in keeping code that only provides 1 HZ PIEs. + * The same exact behavior can be accomplished by using the update interrupt + * event (UIE). Maybe down the line the RTC peripheral will suck less in which + * case we can re-introduce PIE support. + */ + #include <linux/bcd.h> #include <linux/completion.h> #include <linux/delay.h> @@ -144,14 +153,13 @@ static void bfin_rtc_sync_pending(struct device *dev) * Initialize the RTC. Enable pre-scaler to scale RTC clock * to 1Hz and clear interrupt/status registers. */ -static void bfin_rtc_reset(struct device *dev) +static void bfin_rtc_reset(struct device *dev, u16 rtc_ictl) { struct bfin_rtc *rtc = dev_get_drvdata(dev); dev_dbg_stamp(dev); bfin_rtc_sync_pending(dev); bfin_write_RTC_PREN(0x1); - bfin_write_RTC_ICTL(RTC_ISTAT_WRITE_COMPLETE); - bfin_write_RTC_SWCNT(0); + bfin_write_RTC_ICTL(rtc_ictl); bfin_write_RTC_ALARM(0); bfin_write_RTC_ISTAT(0xFFFF); rtc->rtc_wrote_regs = 0; @@ -194,14 +202,6 @@ static irqreturn_t bfin_rtc_interrupt(int irq, void *dev_id) } } - if (rtc_ictl & RTC_ISTAT_STOPWATCH) { - if (rtc_istat & RTC_ISTAT_STOPWATCH) { - bfin_write_RTC_ISTAT(RTC_ISTAT_STOPWATCH); - events |= RTC_PF | RTC_IRQF; - bfin_write_RTC_SWCNT(rtc->rtc_dev->irq_freq); - } - } - if (rtc_ictl & RTC_ISTAT_SEC) { if (rtc_istat & RTC_ISTAT_SEC) { bfin_write_RTC_ISTAT(RTC_ISTAT_SEC); @@ -218,32 +218,12 @@ static irqreturn_t bfin_rtc_interrupt(int irq, void *dev_id) return IRQ_NONE; } -static int bfin_rtc_open(struct device *dev) -{ - int ret; - - dev_dbg_stamp(dev); - - ret = request_irq(IRQ_RTC, bfin_rtc_interrupt, IRQF_SHARED, to_platform_device(dev)->name, dev); - if (!ret) - bfin_rtc_reset(dev); - - return ret; -} - -static void bfin_rtc_release(struct device *dev) -{ - dev_dbg_stamp(dev); - bfin_rtc_reset(dev); - free_irq(IRQ_RTC, dev); -} - -static void bfin_rtc_int_set(struct bfin_rtc *rtc, u16 rtc_int) +static void bfin_rtc_int_set(u16 rtc_int) { bfin_write_RTC_ISTAT(rtc_int); bfin_write_RTC_ICTL(bfin_read_RTC_ICTL() | rtc_int); } -static void bfin_rtc_int_clear(struct bfin_rtc *rtc, u16 rtc_int) +static void bfin_rtc_int_clear(u16 rtc_int) { bfin_write_RTC_ICTL(bfin_read_RTC_ICTL() & rtc_int); } @@ -252,7 +232,7 @@ static void bfin_rtc_int_set_alarm(struct bfin_rtc *rtc) /* Blackfin has different bits for whether the alarm is * more than 24 hours away. */ - bfin_rtc_int_set(rtc, (rtc->rtc_alarm.tm_yday == -1 ? RTC_ISTAT_ALARM : RTC_ISTAT_ALARM_DAY)); + bfin_rtc_int_set(rtc->rtc_alarm.tm_yday == -1 ? RTC_ISTAT_ALARM : RTC_ISTAT_ALARM_DAY); } static int bfin_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) { @@ -264,23 +244,13 @@ static int bfin_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long ar bfin_rtc_sync_pending(dev); switch (cmd) { - case RTC_PIE_ON: - dev_dbg_stamp(dev); - bfin_rtc_int_set(rtc, RTC_ISTAT_STOPWATCH); - bfin_write_RTC_SWCNT(rtc->rtc_dev->irq_freq); - break; - case RTC_PIE_OFF: - dev_dbg_stamp(dev); - bfin_rtc_int_clear(rtc, ~RTC_ISTAT_STOPWATCH); - break; - case RTC_UIE_ON: dev_dbg_stamp(dev); - bfin_rtc_int_set(rtc, RTC_ISTAT_SEC); + bfin_rtc_int_set(RTC_ISTAT_SEC); break; case RTC_UIE_OFF: dev_dbg_stamp(dev); - bfin_rtc_int_clear(rtc, ~RTC_ISTAT_SEC); + bfin_rtc_int_clear(~RTC_ISTAT_SEC); break; case RTC_AIE_ON: @@ -289,7 +259,7 @@ static int bfin_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long ar break; case RTC_AIE_OFF: dev_dbg_stamp(dev); - bfin_rtc_int_clear(rtc, ~(RTC_ISTAT_ALARM | RTC_ISTAT_ALARM_DAY)); + bfin_rtc_int_clear(~(RTC_ISTAT_ALARM | RTC_ISTAT_ALARM_DAY)); break; default: @@ -371,64 +341,64 @@ static int bfin_rtc_proc(struct device *dev, struct seq_file *seq) seq_printf(seq, "alarm_IRQ\t: %s\n" "wkalarm_IRQ\t: %s\n" - "seconds_IRQ\t: %s\n" - "periodic_IRQ\t: %s\n", + "seconds_IRQ\t: %s\n", yesno(ictl & RTC_ISTAT_ALARM), yesno(ictl & RTC_ISTAT_ALARM_DAY), - yesno(ictl & RTC_ISTAT_SEC), - yesno(ictl & RTC_ISTAT_STOPWATCH)); + yesno(ictl & RTC_ISTAT_SEC)); return 0; #undef yesno } -/** - * bfin_irq_set_freq - make sure hardware supports requested freq - * @dev: pointer to RTC device structure - * @freq: requested frequency rate - * - * The Blackfin RTC can only generate periodic events at 1 per - * second (1 Hz), so reject any attempt at changing it. - */ -static int bfin_irq_set_freq(struct device *dev, int freq) -{ - dev_dbg_stamp(dev); - return -ENOTTY; -} - static struct rtc_class_ops bfin_rtc_ops = { - .open = bfin_rtc_open, - .release = bfin_rtc_release, .ioctl = bfin_rtc_ioctl, .read_time = bfin_rtc_read_time, .set_time = bfin_rtc_set_time, .read_alarm = bfin_rtc_read_alarm, .set_alarm = bfin_rtc_set_alarm, .proc = bfin_rtc_proc, - .irq_set_freq = bfin_irq_set_freq, }; static int __devinit bfin_rtc_probe(struct platform_device *pdev) { struct bfin_rtc *rtc; + struct device *dev = &pdev->dev; int ret = 0; + unsigned long timeout; - dev_dbg_stamp(&pdev->dev); + dev_dbg_stamp(dev); + /* Allocate memory for our RTC struct */ rtc = kzalloc(sizeof(*rtc), GFP_KERNEL); if (unlikely(!rtc)) return -ENOMEM; + platform_set_drvdata(pdev, rtc); + device_init_wakeup(dev, 1); - rtc->rtc_dev = rtc_device_register(pdev->name, &pdev->dev, &bfin_rtc_ops, THIS_MODULE); - if (IS_ERR(rtc)) { - ret = PTR_ERR(rtc->rtc_dev); + /* Grab the IRQ and init the hardware */ + ret = request_irq(IRQ_RTC, bfin_rtc_interrupt, IRQF_SHARED, pdev->name, dev); + if (unlikely(ret)) goto err; - } - rtc->rtc_dev->irq_freq = 1; + /* sometimes the bootloader touched things, but the write complete was not + * enabled, so let's just do a quick timeout here since the IRQ will not fire ... + */ + timeout = jiffies + HZ; + while (bfin_read_RTC_ISTAT() & RTC_ISTAT_WRITE_PENDING) + if (time_after(jiffies, timeout)) + break; + bfin_rtc_reset(dev, RTC_ISTAT_WRITE_COMPLETE); + bfin_write_RTC_SWCNT(0); - platform_set_drvdata(pdev, rtc); + /* Register our RTC with the RTC framework */ + rtc->rtc_dev = rtc_device_register(pdev->name, dev, &bfin_rtc_ops, THIS_MODULE); + if (unlikely(IS_ERR(rtc))) { + ret = PTR_ERR(rtc->rtc_dev); + goto err_irq; + } return 0; + err_irq: + free_irq(IRQ_RTC, dev); err: kfree(rtc); return ret; @@ -437,7 +407,10 @@ static int __devinit bfin_rtc_probe(struct platform_device *pdev) static int __devexit bfin_rtc_remove(struct platform_device *pdev) { struct bfin_rtc *rtc = platform_get_drvdata(pdev); + struct device *dev = &pdev->dev; + bfin_rtc_reset(dev, 0); + free_irq(IRQ_RTC, dev); rtc_device_unregister(rtc->rtc_dev); platform_set_drvdata(pdev, NULL); kfree(rtc); @@ -445,6 +418,32 @@ static int __devexit bfin_rtc_remove(struct platform_device *pdev) return 0; } +#ifdef CONFIG_PM +static int bfin_rtc_suspend(struct platform_device *pdev, pm_message_t state) +{ + if (device_may_wakeup(&pdev->dev)) { + enable_irq_wake(IRQ_RTC); + bfin_rtc_sync_pending(&pdev->dev); + } else + bfin_rtc_int_clear(-1); + + return 0; +} + +static int bfin_rtc_resume(struct platform_device *pdev) +{ + if (device_may_wakeup(&pdev->dev)) + disable_irq_wake(IRQ_RTC); + else + bfin_write_RTC_ISTAT(-1); + + return 0; +} +#else +# define bfin_rtc_suspend NULL +# define bfin_rtc_resume NULL +#endif + static struct platform_driver bfin_rtc_driver = { .driver = { .name = "rtc-bfin", @@ -452,6 +451,8 @@ static struct platform_driver bfin_rtc_driver = { }, .probe = bfin_rtc_probe, .remove = __devexit_p(bfin_rtc_remove), + .suspend = bfin_rtc_suspend, + .resume = bfin_rtc_resume, }; static int __init bfin_rtc_init(void) |