diff options
Diffstat (limited to 'drivers/rtc/rtc-at91rm9200.c')
| -rw-r--r-- | drivers/rtc/rtc-at91rm9200.c | 135 |
1 files changed, 112 insertions, 23 deletions
diff --git a/drivers/rtc/rtc-at91rm9200.c b/drivers/rtc/rtc-at91rm9200.c index 0eab77b22340..741892632ae0 100644 --- a/drivers/rtc/rtc-at91rm9200.c +++ b/drivers/rtc/rtc-at91rm9200.c @@ -25,13 +25,13 @@ #include <linux/rtc.h> #include <linux/bcd.h> #include <linux/interrupt.h> +#include <linux/spinlock.h> #include <linux/ioctl.h> #include <linux/completion.h> #include <linux/io.h> #include <linux/of.h> #include <linux/of_device.h> - -#include <asm/uaccess.h> +#include <linux/uaccess.h> #include "rtc-at91rm9200.h" @@ -42,10 +42,65 @@ #define AT91_RTC_EPOCH 1900UL /* just like arch/arm/common/rtctime.c */ +struct at91_rtc_config { + bool use_shadow_imr; +}; + +static const struct at91_rtc_config *at91_rtc_config; 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 DEFINE_SPINLOCK(at91_rtc_lock); +static u32 at91_rtc_shadow_imr; + +static void at91_rtc_write_ier(u32 mask) +{ + unsigned long flags; + + spin_lock_irqsave(&at91_rtc_lock, flags); + at91_rtc_shadow_imr |= mask; + at91_rtc_write(AT91_RTC_IER, mask); + spin_unlock_irqrestore(&at91_rtc_lock, flags); +} + +static void at91_rtc_write_idr(u32 mask) +{ + unsigned long flags; + + spin_lock_irqsave(&at91_rtc_lock, flags); + at91_rtc_write(AT91_RTC_IDR, mask); + /* + * Register read back (of any RTC-register) needed to make sure + * IDR-register write has reached the peripheral before updating + * shadow mask. + * + * Note that there is still a possibility that the mask is updated + * before interrupts have actually been disabled in hardware. The only + * way to be certain would be to poll the IMR-register, which is is + * the very register we are trying to emulate. The register read back + * is a reasonable heuristic. + */ + at91_rtc_read(AT91_RTC_SR); + at91_rtc_shadow_imr &= ~mask; + spin_unlock_irqrestore(&at91_rtc_lock, flags); +} + +static u32 at91_rtc_read_imr(void) +{ + unsigned long flags; + u32 mask; + + if (at91_rtc_config->use_shadow_imr) { + spin_lock_irqsave(&at91_rtc_lock, flags); + mask = at91_rtc_shadow_imr; + spin_unlock_irqrestore(&at91_rtc_lock, flags); + } else { + mask = at91_rtc_read(AT91_RTC_IMR); + } + + return mask; +} /* * Decode time/date into rtc_time structure @@ -110,9 +165,9 @@ 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_write(AT91_RTC_IER, AT91_RTC_ACKUPD); + at91_rtc_write_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_write_idr(AT91_RTC_ACKUPD); at91_rtc_write(AT91_RTC_TIMR, bin2bcd(tm->tm_sec) << 0 @@ -144,7 +199,7 @@ 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_read(AT91_RTC_IMR) & AT91_RTC_ALARM) + alrm->enabled = (at91_rtc_read_imr() & AT91_RTC_ALARM) ? 1 : 0; dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__, @@ -169,7 +224,7 @@ static int at91_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm) tm.tm_min = alrm->time.tm_min; tm.tm_sec = alrm->time.tm_sec; - at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM); + at91_rtc_write_idr(AT91_RTC_ALARM); at91_rtc_write(AT91_RTC_TIMALR, bin2bcd(tm.tm_sec) << 0 | bin2bcd(tm.tm_min) << 8 @@ -182,7 +237,7 @@ 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_write(AT91_RTC_IER, AT91_RTC_ALARM); + at91_rtc_write_ier(AT91_RTC_ALARM); } dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__, @@ -198,9 +253,9 @@ 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_write(AT91_RTC_IER, AT91_RTC_ALARM); + at91_rtc_write_ier(AT91_RTC_ALARM); } else - at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ALARM); + at91_rtc_write_idr(AT91_RTC_ALARM); return 0; } @@ -209,7 +264,7 @@ 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); + unsigned long imr = at91_rtc_read_imr(); seq_printf(seq, "update_IRQ\t: %s\n", (imr & AT91_RTC_ACKUPD) ? "yes" : "no"); @@ -229,7 +284,7 @@ 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_read(AT91_RTC_IMR); + rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read_imr(); if (rtsr) { /* this interrupt is shared! Is it ours? */ if (rtsr & AT91_RTC_ALARM) events |= (RTC_AF | RTC_IRQF); @@ -250,6 +305,43 @@ static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id) return IRQ_NONE; /* not handled */ } +static const struct at91_rtc_config at91rm9200_config = { +}; + +static const struct at91_rtc_config at91sam9x5_config = { + .use_shadow_imr = true, +}; + +#ifdef CONFIG_OF +static const struct of_device_id at91_rtc_dt_ids[] = { + { + .compatible = "atmel,at91rm9200-rtc", + .data = &at91rm9200_config, + }, { + .compatible = "atmel,at91sam9x5-rtc", + .data = &at91sam9x5_config, + }, { + /* sentinel */ + } +}; +MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids); +#endif + +static const struct at91_rtc_config * +at91_rtc_get_config(struct platform_device *pdev) +{ + const struct of_device_id *match; + + if (pdev->dev.of_node) { + match = of_match_node(at91_rtc_dt_ids, pdev->dev.of_node); + if (!match) + return NULL; + return (const struct at91_rtc_config *)match->data; + } + + return &at91rm9200_config; +} + static const struct rtc_class_ops at91_rtc_ops = { .read_time = at91_rtc_readtime, .set_time = at91_rtc_settime, @@ -268,6 +360,10 @@ static int __init at91_rtc_probe(struct platform_device *pdev) struct resource *regs; int ret = 0; + at91_rtc_config = at91_rtc_get_config(pdev); + if (!at91_rtc_config) + return -ENODEV; + regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!regs) { dev_err(&pdev->dev, "no mmio resource defined\n"); @@ -290,7 +386,7 @@ static int __init at91_rtc_probe(struct platform_device *pdev) at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */ /* Disable all interrupts */ - at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM | + at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM | AT91_RTC_SECEV | AT91_RTC_TIMEV | AT91_RTC_CALEV); @@ -335,14 +431,13 @@ static int __exit at91_rtc_remove(struct platform_device *pdev) struct rtc_device *rtc = platform_get_drvdata(pdev); /* Disable all interrupts */ - at91_rtc_write(AT91_RTC_IDR, AT91_RTC_ACKUPD | AT91_RTC_ALARM | + at91_rtc_write_idr(AT91_RTC_ACKUPD | AT91_RTC_ALARM | AT91_RTC_SECEV | AT91_RTC_TIMEV | AT91_RTC_CALEV); free_irq(irq, pdev); rtc_device_unregister(rtc); iounmap(at91_rtc_regs); - platform_set_drvdata(pdev, NULL); return 0; } @@ -358,13 +453,13 @@ 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_imr = at91_rtc_read(AT91_RTC_IMR) + at91_rtc_imr = at91_rtc_read_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_imr); + at91_rtc_write_idr(at91_rtc_imr); } return 0; } @@ -375,7 +470,7 @@ static int at91_rtc_resume(struct device *dev) if (device_may_wakeup(dev)) disable_irq_wake(irq); else - at91_rtc_write(AT91_RTC_IER, at91_rtc_imr); + at91_rtc_write_ier(at91_rtc_imr); } return 0; } @@ -383,12 +478,6 @@ static int at91_rtc_resume(struct device *dev) static SIMPLE_DEV_PM_OPS(at91_rtc_pm_ops, at91_rtc_suspend, at91_rtc_resume); -static const struct of_device_id at91_rtc_dt_ids[] = { - { .compatible = "atmel,at91rm9200-rtc" }, - { /* sentinel */ } -}; -MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids); - static struct platform_driver at91_rtc_driver = { .remove = __exit_p(at91_rtc_remove), .driver = { |