From 3dcad5ff08f65ae30832220a0e0ee2eac3502a1a Mon Sep 17 00:00:00 2001 From: John Stultz Date: Fri, 27 May 2011 11:33:18 -0700 Subject: rtc: Avoid accumulating time drift in suspend/resume MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Because the RTC interface is only a second granular interface, each time we read from the RTC for suspend/resume, we introduce a half second (on average) of error. In order to avoid this error accumulating as the system is suspended over and over, this patch measures the time delta between the RTC and the system CLOCK_REALTIME. If the delta is less then 2 seconds from the last suspend, we compensate by using the previous time delta (keeping it close). If it is larger then 2 seconds, we assume the clock was set or has been changed, so we do no correction and update the delta. Note: If NTP is running, ths could seem to "fight" with the NTP corrected time, where as if the system time was off by 1 second, and NTP slewed the value in, a suspend/resume cycle could undo this correction, by trying to restore the previous offset from the RTC. However, without this patch, since each read could cause almost a full second worth of error, its possible to get almost 2 seconds of error just from the suspend/resume cycle alone, so this about equal to any offset added by the compensation. Further on systems that suspend/resume frequently, this should keep time closer then NTP could compensate for if the errors were allowed to accumulate. Credits to Arve Hjønnevåg for suggesting this solution. This patch also improves some of the variable names and adds more clear comments. CC: Arve Hjønnevåg CC: Thomas Gleixner Signed-off-by: John Stultz --- drivers/rtc/class.c | 65 +++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 48 insertions(+), 17 deletions(-) (limited to 'drivers/rtc') diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c index 4194e59e14c..01a7df5317c 100644 --- a/drivers/rtc/class.c +++ b/drivers/rtc/class.c @@ -41,20 +41,41 @@ static void rtc_device_release(struct device *dev) * system's wall clock; restore it on resume(). */ -static time_t oldtime; -static struct timespec oldts; +static struct timespec old_rtc, old_system, old_delta; + static int rtc_suspend(struct device *dev, pm_message_t mesg) { struct rtc_device *rtc = to_rtc_device(dev); struct rtc_time tm; - + struct timespec delta, delta_delta; if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0) return 0; + /* snapshot the current RTC and system time at suspend*/ rtc_read_time(rtc, &tm); - ktime_get_ts(&oldts); - rtc_tm_to_time(&tm, &oldtime); + getnstimeofday(&old_system); + rtc_tm_to_time(&tm, &old_rtc.tv_sec); + + + /* + * To avoid drift caused by repeated suspend/resumes, + * which each can add ~1 second drift error, + * try to compensate so the difference in system time + * and rtc time stays close to constant. + */ + delta = timespec_sub(old_system, old_rtc); + delta_delta = timespec_sub(delta, old_delta); + if (abs(delta_delta.tv_sec) >= 2) { + /* + * if delta_delta is too large, assume time correction + * has occured and set old_delta to the current delta. + */ + old_delta = delta; + } else { + /* Otherwise try to adjust old_system to compensate */ + old_system = timespec_sub(old_system, delta_delta); + } return 0; } @@ -63,32 +84,42 @@ static int rtc_resume(struct device *dev) { struct rtc_device *rtc = to_rtc_device(dev); struct rtc_time tm; - time_t newtime; - struct timespec time; - struct timespec newts; + struct timespec new_system, new_rtc; + struct timespec sleep_time; if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0) return 0; - ktime_get_ts(&newts); + /* snapshot the current rtc and system time at resume */ + getnstimeofday(&new_system); rtc_read_time(rtc, &tm); if (rtc_valid_tm(&tm) != 0) { pr_debug("%s: bogus resume time\n", dev_name(&rtc->dev)); return 0; } - rtc_tm_to_time(&tm, &newtime); - if (newtime <= oldtime) { - if (newtime < oldtime) + rtc_tm_to_time(&tm, &new_rtc.tv_sec); + new_rtc.tv_nsec = 0; + + if (new_rtc.tv_sec <= old_rtc.tv_sec) { + if (new_rtc.tv_sec < old_rtc.tv_sec) pr_debug("%s: time travel!\n", dev_name(&rtc->dev)); return 0; } - /* calculate the RTC time delta */ - set_normalized_timespec(&time, newtime - oldtime, 0); - /* subtract kernel time between rtc_suspend to rtc_resume */ - time = timespec_sub(time, timespec_sub(newts, oldts)); + /* calculate the RTC time delta (sleep time)*/ + sleep_time = timespec_sub(new_rtc, old_rtc); + + /* + * Since these RTC suspend/resume handlers are not called + * at the very end of suspend or the start of resume, + * some run-time may pass on either sides of the sleep time + * so subtract kernel run-time between rtc_suspend to rtc_resume + * to keep things accurate. + */ + sleep_time = timespec_sub(sleep_time, + timespec_sub(new_system, old_system)); - timekeeping_inject_sleeptime(&time); + timekeeping_inject_sleeptime(&sleep_time); return 0; } -- cgit v1.2.3-70-g09d2 From 07187ee13f2b4ba183d4a4832ea153dbb2e030d3 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Wed, 22 Jun 2011 23:20:14 +0200 Subject: rtc: vt8500: Use define instead of hardcoded value for status bit Fixes the vt8500 driver to use a define value for the isr is-alarm bit. Cc: Alexey Charkov Signed-off-by: Wolfram Sang Signed-off-by: John Stultz --- drivers/rtc/rtc-vt8500.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'drivers/rtc') diff --git a/drivers/rtc/rtc-vt8500.c b/drivers/rtc/rtc-vt8500.c index efd6066b5cd..f93f412423c 100644 --- a/drivers/rtc/rtc-vt8500.c +++ b/drivers/rtc/rtc-vt8500.c @@ -74,6 +74,8 @@ #define VT8500_RTC_CR_SM_SEC (1 << 3) /* 0: 1Hz/60, 1: 1Hz */ #define VT8500_RTC_CR_CALIB (1 << 4) /* Enable calibration */ +#define VT8500_RTC_IS_ALARM (1 << 0) /* Alarm interrupt status */ + struct vt8500_rtc { void __iomem *regbase; struct resource *res; @@ -96,7 +98,7 @@ static irqreturn_t vt8500_rtc_irq(int irq, void *dev_id) spin_unlock(&vt8500_rtc->lock); - if (isr & 1) + if (isr & VT8500_RTC_IS_ALARM) events |= RTC_AF | RTC_IRQF; rtc_update_irq(vt8500_rtc->rtc, 1, events); @@ -161,8 +163,8 @@ static int vt8500_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) alrm->time.tm_sec = bcd2bin((alarm & TIME_SEC_MASK)); alrm->enabled = (alarm & ALARM_ENABLE_MASK) ? 1 : 0; + alrm->pending = (isr & VT8500_RTC_IS_ALARM) ? 1 : 0; - alrm->pending = (isr & 1) ? 1 : 0; return rtc_valid_tm(&alrm->time); } -- cgit v1.2.3-70-g09d2 From 47eac337cd87464b90d0ad2eb2a060036a95b649 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Wed, 25 May 2011 12:56:49 +0200 Subject: rtc: stmp3xxx: Restore register definitions The stmp3xxx driver used to include register names from a stmp-specific include. Because of consolidation, plat-stmp has now been removed and merged with the compatible mach-mxs. Restore the register names directly in the driver and rename them to be specific to this driver. Signed-off-by: Wolfram Sang Tested-by: Shawn Guo Signed-off-by: John Stultz --- drivers/rtc/rtc-stmp3xxx.c | 97 ++++++++++++++++++++++++++++------------------ 1 file changed, 60 insertions(+), 37 deletions(-) (limited to 'drivers/rtc') diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c index 572e9534b59..e54bea07606 100644 --- a/drivers/rtc/rtc-stmp3xxx.c +++ b/drivers/rtc/rtc-stmp3xxx.c @@ -26,7 +26,25 @@ #include #include -#include + +#define STMP3XXX_RTC_CTRL 0x0 +#define STMP3XXX_RTC_CTRL_ALARM_IRQ_EN 0x00000001 +#define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN 0x00000002 +#define STMP3XXX_RTC_CTRL_ALARM_IRQ 0x00000004 +#define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ 0x00000008 + +#define STMP3XXX_RTC_STAT 0x10 +#define STMP3XXX_RTC_STAT_STALE_SHIFT 16 +#define STMP3XXX_RTC_STAT_RTC_PRESENT 0x80000000 + +#define STMP3XXX_RTC_SECONDS 0x30 + +#define STMP3XXX_RTC_ALARM 0x40 + +#define STMP3XXX_RTC_PERSISTENT0 0x60 +#define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN 0x00000002 +#define STMP3XXX_RTC_PERSISTENT0_ALARM_EN 0x00000004 +#define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE 0x00000080 struct stmp3xxx_rtc_data { struct rtc_device *rtc; @@ -42,8 +60,8 @@ static void stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data) * NEW_REGS/STALE_REGS bitfields go. In fact it's 0x1=P0, * 0x2=P1, .., 0x20=P5, 0x40=ALARM, 0x80=SECONDS */ - while (__raw_readl(rtc_data->io + HW_RTC_STAT) & - BF(0x80, RTC_STAT_STALE_REGS)) + while (__raw_readl(rtc_data->io + STMP3XXX_RTC_STAT) & + (0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT)) cpu_relax(); } @@ -53,7 +71,8 @@ static int stmp3xxx_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm) struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); stmp3xxx_wait_time(rtc_data); - rtc_time_to_tm(__raw_readl(rtc_data->io + HW_RTC_SECONDS), rtc_tm); + rtc_time_to_tm(__raw_readl(rtc_data->io + STMP3XXX_RTC_SECONDS), + rtc_tm); return 0; } @@ -61,7 +80,7 @@ static int stmp3xxx_rtc_set_mmss(struct device *dev, unsigned long t) { struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); - __raw_writel(t, rtc_data->io + HW_RTC_SECONDS); + __raw_writel(t, rtc_data->io + STMP3XXX_RTC_SECONDS); stmp3xxx_wait_time(rtc_data); return 0; } @@ -73,18 +92,19 @@ static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id) u32 status; u32 events = 0; - status = __raw_readl(rtc_data->io + HW_RTC_CTRL) & - (BM_RTC_CTRL_ALARM_IRQ | BM_RTC_CTRL_ONEMSEC_IRQ); + status = __raw_readl(rtc_data->io + STMP3XXX_RTC_CTRL) & + (STMP3XXX_RTC_CTRL_ALARM_IRQ | + STMP3XXX_RTC_CTRL_ONEMSEC_IRQ); - if (status & BM_RTC_CTRL_ALARM_IRQ) { - stmp3xxx_clearl(BM_RTC_CTRL_ALARM_IRQ, - rtc_data->io + HW_RTC_CTRL); + if (status & STMP3XXX_RTC_CTRL_ALARM_IRQ) { + stmp3xxx_clearl(STMP3XXX_RTC_CTRL_ALARM_IRQ, + rtc_data->io + STMP3XXX_RTC_CTRL); events |= RTC_AF | RTC_IRQF; } - if (status & BM_RTC_CTRL_ONEMSEC_IRQ) { - stmp3xxx_clearl(BM_RTC_CTRL_ONEMSEC_IRQ, - rtc_data->io + HW_RTC_CTRL); + if (status & STMP3XXX_RTC_CTRL_ONEMSEC_IRQ) { + stmp3xxx_clearl(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ, + rtc_data->io + STMP3XXX_RTC_CTRL); if (++rtc_data->irq_count % 1000 == 0) { events |= RTC_UF | RTC_IRQF; rtc_data->irq_count = 0; @@ -100,17 +120,17 @@ static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id) static int stmp3xxx_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); - void __iomem *p = rtc_data->io + HW_RTC_PERSISTENT0, - *ctl = rtc_data->io + HW_RTC_CTRL; + void __iomem *p = rtc_data->io + STMP3XXX_RTC_PERSISTENT0, + *ctl = rtc_data->io + STMP3XXX_RTC_CTRL; if (enabled) { - stmp3xxx_setl(BM_RTC_PERSISTENT0_ALARM_EN | - BM_RTC_PERSISTENT0_ALARM_WAKE_EN, p); - stmp3xxx_setl(BM_RTC_CTRL_ALARM_IRQ_EN, ctl); + stmp3xxx_setl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | + STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN, p); + stmp3xxx_setl(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, ctl); } else { - stmp3xxx_clearl(BM_RTC_PERSISTENT0_ALARM_EN | - BM_RTC_PERSISTENT0_ALARM_WAKE_EN, p); - stmp3xxx_clearl(BM_RTC_CTRL_ALARM_IRQ_EN, ctl); + stmp3xxx_clearl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | + STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN, p); + stmp3xxx_clearl(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, ctl); } return 0; } @@ -119,7 +139,8 @@ static int stmp3xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) { struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); - rtc_time_to_tm(__raw_readl(rtc_data->io + HW_RTC_ALARM), &alm->time); + rtc_time_to_tm(__raw_readl(rtc_data->io + STMP3XXX_RTC_ALARM), + &alm->time); return 0; } @@ -129,7 +150,7 @@ static int stmp3xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); rtc_tm_to_time(&alm->time, &t); - __raw_writel(t, rtc_data->io + HW_RTC_ALARM); + __raw_writel(t, rtc_data->io + STMP3XXX_RTC_ALARM); return 0; } @@ -149,8 +170,9 @@ static int stmp3xxx_rtc_remove(struct platform_device *pdev) if (!rtc_data) return 0; - stmp3xxx_clearl(BM_RTC_CTRL_ONEMSEC_IRQ_EN | BM_RTC_CTRL_ALARM_IRQ_EN, - rtc_data->io + HW_RTC_CTRL); + stmp3xxx_clearl(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN | + STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, + rtc_data->io + STMP3XXX_RTC_CTRL); free_irq(rtc_data->irq_alarm, &pdev->dev); free_irq(rtc_data->irq_1msec, &pdev->dev); rtc_device_unregister(rtc_data->rtc); @@ -187,18 +209,18 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) rtc_data->irq_alarm = platform_get_irq(pdev, 0); rtc_data->irq_1msec = platform_get_irq(pdev, 1); - if (!(__raw_readl(HW_RTC_STAT + rtc_data->io) & - BM_RTC_STAT_RTC_PRESENT)) { + if (!(__raw_readl(STMP3XXX_RTC_STAT + rtc_data->io) & + STMP3XXX_RTC_STAT_RTC_PRESENT)) { dev_err(&pdev->dev, "no device onboard\n"); err = -ENODEV; goto out_remap; } stmp3xxx_reset_block(rtc_data->io, true); - stmp3xxx_clearl(BM_RTC_PERSISTENT0_ALARM_EN | - BM_RTC_PERSISTENT0_ALARM_WAKE_EN | - BM_RTC_PERSISTENT0_ALARM_WAKE, - rtc_data->io + HW_RTC_PERSISTENT0); + stmp3xxx_clearl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | + STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN | + STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE, + rtc_data->io + STMP3XXX_RTC_PERSISTENT0); rtc_data->rtc = rtc_device_register(pdev->name, &pdev->dev, &stmp3xxx_rtc_ops, THIS_MODULE); if (IS_ERR(rtc_data->rtc)) { @@ -229,8 +251,9 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) out_irq1: free_irq(rtc_data->irq_alarm, &pdev->dev); out_irq_alarm: - stmp3xxx_clearl(BM_RTC_CTRL_ONEMSEC_IRQ_EN | BM_RTC_CTRL_ALARM_IRQ_EN, - rtc_data->io + HW_RTC_CTRL); + stmp3xxx_clearl(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN | + STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, + rtc_data->io + STMP3XXX_RTC_CTRL); rtc_device_unregister(rtc_data->rtc); out_remap: iounmap(rtc_data->io); @@ -250,10 +273,10 @@ static int stmp3xxx_rtc_resume(struct platform_device *dev) struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(dev); stmp3xxx_reset_block(rtc_data->io, true); - stmp3xxx_clearl(BM_RTC_PERSISTENT0_ALARM_EN | - BM_RTC_PERSISTENT0_ALARM_WAKE_EN | - BM_RTC_PERSISTENT0_ALARM_WAKE, - rtc_data->io + HW_RTC_PERSISTENT0); + stmp3xxx_clearl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | + STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN | + STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE, + rtc_data->io + STMP3XXX_RTC_PERSISTENT0); return 0; } #else -- cgit v1.2.3-70-g09d2 From 46b21218145ecef0936eb4338a9e0ffef84f00cf Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Wed, 25 May 2011 12:56:50 +0200 Subject: rtc: stmp3xxx: Port stmp-functions to mxs-equivalents The stmp3xxx driver used to include functions from a stmp-specific include. Because of consolidation, plat-stmp has now been removed and merged with the compatible mach-mxs. Use the apropriate mxs-functions for transition. The accessors will be converted to readl/writel in a later patch. Signed-off-by: Wolfram Sang Tested-by: Shawn Guo Signed-off-by: John Stultz --- drivers/rtc/Kconfig | 6 +++--- drivers/rtc/rtc-stmp3xxx.c | 28 ++++++++++++++-------------- 2 files changed, 17 insertions(+), 17 deletions(-) (limited to 'drivers/rtc') diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index ce2aabf5c55..dcb61e23b98 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -981,11 +981,11 @@ config RTC_DRV_COH901331 config RTC_DRV_STMP - tristate "Freescale STMP3xxx RTC" - depends on ARCH_STMP3XXX + tristate "Freescale STMP3xxx/i.MX23/i.MX28 RTC" + depends on ARCH_MXS help If you say yes here you will get support for the onboard - STMP3xxx RTC. + STMP3xxx/i.MX23/i.MX28 RTC. This driver can also be built as a module. If so, the module will be called rtc-stmp3xxx. diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c index e54bea07606..ac40f971a40 100644 --- a/drivers/rtc/rtc-stmp3xxx.c +++ b/drivers/rtc/rtc-stmp3xxx.c @@ -24,8 +24,8 @@ #include #include -#include -#include +#include +#include #define STMP3XXX_RTC_CTRL 0x0 #define STMP3XXX_RTC_CTRL_ALARM_IRQ_EN 0x00000001 @@ -97,13 +97,13 @@ static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id) STMP3XXX_RTC_CTRL_ONEMSEC_IRQ); if (status & STMP3XXX_RTC_CTRL_ALARM_IRQ) { - stmp3xxx_clearl(STMP3XXX_RTC_CTRL_ALARM_IRQ, + __mxs_clrl(STMP3XXX_RTC_CTRL_ALARM_IRQ, rtc_data->io + STMP3XXX_RTC_CTRL); events |= RTC_AF | RTC_IRQF; } if (status & STMP3XXX_RTC_CTRL_ONEMSEC_IRQ) { - stmp3xxx_clearl(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ, + __mxs_clrl(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ, rtc_data->io + STMP3XXX_RTC_CTRL); if (++rtc_data->irq_count % 1000 == 0) { events |= RTC_UF | RTC_IRQF; @@ -124,13 +124,13 @@ static int stmp3xxx_alarm_irq_enable(struct device *dev, unsigned int enabled) *ctl = rtc_data->io + STMP3XXX_RTC_CTRL; if (enabled) { - stmp3xxx_setl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | + __mxs_setl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN, p); - stmp3xxx_setl(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, ctl); + __mxs_setl(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, ctl); } else { - stmp3xxx_clearl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | + __mxs_clrl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN, p); - stmp3xxx_clearl(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, ctl); + __mxs_clrl(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, ctl); } return 0; } @@ -170,7 +170,7 @@ static int stmp3xxx_rtc_remove(struct platform_device *pdev) if (!rtc_data) return 0; - stmp3xxx_clearl(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN | + __mxs_clrl(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN | STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, rtc_data->io + STMP3XXX_RTC_CTRL); free_irq(rtc_data->irq_alarm, &pdev->dev); @@ -216,8 +216,8 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) goto out_remap; } - stmp3xxx_reset_block(rtc_data->io, true); - stmp3xxx_clearl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | + mxs_reset_block(rtc_data->io); + __mxs_clrl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE, rtc_data->io + STMP3XXX_RTC_PERSISTENT0); @@ -251,7 +251,7 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) out_irq1: free_irq(rtc_data->irq_alarm, &pdev->dev); out_irq_alarm: - stmp3xxx_clearl(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN | + __mxs_clrl(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN | STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, rtc_data->io + STMP3XXX_RTC_CTRL); rtc_device_unregister(rtc_data->rtc); @@ -272,8 +272,8 @@ static int stmp3xxx_rtc_resume(struct platform_device *dev) { struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(dev); - stmp3xxx_reset_block(rtc_data->io, true); - stmp3xxx_clearl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | + mxs_reset_block(rtc_data->io); + __mxs_clrl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE, rtc_data->io + STMP3XXX_RTC_PERSISTENT0); -- cgit v1.2.3-70-g09d2 From a91d2bab355f3a5caa767d7316f80422bfcd2ad6 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Wed, 25 May 2011 12:56:51 +0200 Subject: rtc: stmp3xxx: Initialize drvdata before registering device Commit f44f7f96a20 ("RTC: Initialize kernel state from RTC") uncovered an issue in a number of RTC drivers, where the drivers call rtc_device_register before initializing the device or platform drvdata. This frequently results in null pointer dereferences when the rtc_device_register immediately makes use of the rtc device, calling rtc_read_alarm. The solution is to ensure the drvdata is initialized prior to registering the rtc device. Signed-off-by: Wolfram Sang Tested-by: Shawn Guo Signed-off-by: John Stultz --- drivers/rtc/rtc-stmp3xxx.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'drivers/rtc') diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c index ac40f971a40..90f05fe6062 100644 --- a/drivers/rtc/rtc-stmp3xxx.c +++ b/drivers/rtc/rtc-stmp3xxx.c @@ -176,6 +176,7 @@ static int stmp3xxx_rtc_remove(struct platform_device *pdev) free_irq(rtc_data->irq_alarm, &pdev->dev); free_irq(rtc_data->irq_1msec, &pdev->dev); rtc_device_unregister(rtc_data->rtc); + platform_set_drvdata(pdev, NULL); iounmap(rtc_data->io); kfree(rtc_data); @@ -216,11 +217,14 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) goto out_remap; } + platform_set_drvdata(pdev, rtc_data); + mxs_reset_block(rtc_data->io); __mxs_clrl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE, rtc_data->io + STMP3XXX_RTC_PERSISTENT0); + rtc_data->rtc = rtc_device_register(pdev->name, &pdev->dev, &stmp3xxx_rtc_ops, THIS_MODULE); if (IS_ERR(rtc_data->rtc)) { @@ -244,8 +248,6 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) goto out_irq1; } - platform_set_drvdata(pdev, rtc_data); - return 0; out_irq1: @@ -256,6 +258,7 @@ out_irq_alarm: rtc_data->io + STMP3XXX_RTC_CTRL); rtc_device_unregister(rtc_data->rtc); out_remap: + platform_set_drvdata(pdev, NULL); iounmap(rtc_data->io); out_free: kfree(rtc_data); -- cgit v1.2.3-70-g09d2 From b5167159d4341d408ef6b941975f2fe8973b2a94 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Wed, 25 May 2011 12:56:52 +0200 Subject: rtc: stmp3xxx: Get rid of mach-specific accessors Replace the accessors with standard readl/writel to remove their platform-dependency. Also, drop __raw_(read|write)l-accessors while we are here. Signed-off-by: Wolfram Sang Tested-by: Shawn Guo Signed-off-by: John Stultz --- drivers/rtc/rtc-stmp3xxx.c | 64 ++++++++++++++++++++++++---------------------- 1 file changed, 34 insertions(+), 30 deletions(-) (limited to 'drivers/rtc') diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c index 90f05fe6062..ad185179694 100644 --- a/drivers/rtc/rtc-stmp3xxx.c +++ b/drivers/rtc/rtc-stmp3xxx.c @@ -18,6 +18,7 @@ */ #include #include +#include #include #include #include @@ -25,9 +26,10 @@ #include #include -#include #define STMP3XXX_RTC_CTRL 0x0 +#define STMP3XXX_RTC_CTRL_SET 0x4 +#define STMP3XXX_RTC_CTRL_CLR 0x8 #define STMP3XXX_RTC_CTRL_ALARM_IRQ_EN 0x00000001 #define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN 0x00000002 #define STMP3XXX_RTC_CTRL_ALARM_IRQ 0x00000004 @@ -42,6 +44,8 @@ #define STMP3XXX_RTC_ALARM 0x40 #define STMP3XXX_RTC_PERSISTENT0 0x60 +#define STMP3XXX_RTC_PERSISTENT0_SET 0x64 +#define STMP3XXX_RTC_PERSISTENT0_CLR 0x68 #define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN 0x00000002 #define STMP3XXX_RTC_PERSISTENT0_ALARM_EN 0x00000004 #define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE 0x00000080 @@ -60,7 +64,7 @@ static void stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data) * NEW_REGS/STALE_REGS bitfields go. In fact it's 0x1=P0, * 0x2=P1, .., 0x20=P5, 0x40=ALARM, 0x80=SECONDS */ - while (__raw_readl(rtc_data->io + STMP3XXX_RTC_STAT) & + while (readl(rtc_data->io + STMP3XXX_RTC_STAT) & (0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT)) cpu_relax(); } @@ -71,8 +75,7 @@ static int stmp3xxx_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm) struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); stmp3xxx_wait_time(rtc_data); - rtc_time_to_tm(__raw_readl(rtc_data->io + STMP3XXX_RTC_SECONDS), - rtc_tm); + rtc_time_to_tm(readl(rtc_data->io + STMP3XXX_RTC_SECONDS), rtc_tm); return 0; } @@ -80,7 +83,7 @@ static int stmp3xxx_rtc_set_mmss(struct device *dev, unsigned long t) { struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); - __raw_writel(t, rtc_data->io + STMP3XXX_RTC_SECONDS); + writel(t, rtc_data->io + STMP3XXX_RTC_SECONDS); stmp3xxx_wait_time(rtc_data); return 0; } @@ -92,19 +95,19 @@ static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id) u32 status; u32 events = 0; - status = __raw_readl(rtc_data->io + STMP3XXX_RTC_CTRL) & + status = readl(rtc_data->io + STMP3XXX_RTC_CTRL) & (STMP3XXX_RTC_CTRL_ALARM_IRQ | STMP3XXX_RTC_CTRL_ONEMSEC_IRQ); if (status & STMP3XXX_RTC_CTRL_ALARM_IRQ) { - __mxs_clrl(STMP3XXX_RTC_CTRL_ALARM_IRQ, - rtc_data->io + STMP3XXX_RTC_CTRL); + writel(STMP3XXX_RTC_CTRL_ALARM_IRQ, + rtc_data->io + STMP3XXX_RTC_CTRL_CLR); events |= RTC_AF | RTC_IRQF; } if (status & STMP3XXX_RTC_CTRL_ONEMSEC_IRQ) { - __mxs_clrl(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ, - rtc_data->io + STMP3XXX_RTC_CTRL); + writel(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ, + rtc_data->io + STMP3XXX_RTC_CTRL_CLR); if (++rtc_data->irq_count % 1000 == 0) { events |= RTC_UF | RTC_IRQF; rtc_data->irq_count = 0; @@ -120,17 +123,19 @@ static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id) static int stmp3xxx_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); - void __iomem *p = rtc_data->io + STMP3XXX_RTC_PERSISTENT0, - *ctl = rtc_data->io + STMP3XXX_RTC_CTRL; if (enabled) { - __mxs_setl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | - STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN, p); - __mxs_setl(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, ctl); + writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | + STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN, + rtc_data->io + STMP3XXX_RTC_PERSISTENT0_SET); + writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, + rtc_data->io + STMP3XXX_RTC_CTRL_SET); } else { - __mxs_clrl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | - STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN, p); - __mxs_clrl(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, ctl); + writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | + STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN, + rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR); + writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, + rtc_data->io + STMP3XXX_RTC_CTRL_CLR); } return 0; } @@ -139,8 +144,7 @@ static int stmp3xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) { struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); - rtc_time_to_tm(__raw_readl(rtc_data->io + STMP3XXX_RTC_ALARM), - &alm->time); + rtc_time_to_tm(readl(rtc_data->io + STMP3XXX_RTC_ALARM), &alm->time); return 0; } @@ -150,7 +154,7 @@ static int stmp3xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); rtc_tm_to_time(&alm->time, &t); - __raw_writel(t, rtc_data->io + STMP3XXX_RTC_ALARM); + writel(t, rtc_data->io + STMP3XXX_RTC_ALARM); return 0; } @@ -170,9 +174,9 @@ static int stmp3xxx_rtc_remove(struct platform_device *pdev) if (!rtc_data) return 0; - __mxs_clrl(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN | + writel(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN | STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, - rtc_data->io + STMP3XXX_RTC_CTRL); + rtc_data->io + STMP3XXX_RTC_CTRL_CLR); free_irq(rtc_data->irq_alarm, &pdev->dev); free_irq(rtc_data->irq_1msec, &pdev->dev); rtc_device_unregister(rtc_data->rtc); @@ -210,7 +214,7 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) rtc_data->irq_alarm = platform_get_irq(pdev, 0); rtc_data->irq_1msec = platform_get_irq(pdev, 1); - if (!(__raw_readl(STMP3XXX_RTC_STAT + rtc_data->io) & + if (!(readl(STMP3XXX_RTC_STAT + rtc_data->io) & STMP3XXX_RTC_STAT_RTC_PRESENT)) { dev_err(&pdev->dev, "no device onboard\n"); err = -ENODEV; @@ -220,10 +224,10 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) platform_set_drvdata(pdev, rtc_data); mxs_reset_block(rtc_data->io); - __mxs_clrl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | + writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE, - rtc_data->io + STMP3XXX_RTC_PERSISTENT0); + rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR); rtc_data->rtc = rtc_device_register(pdev->name, &pdev->dev, &stmp3xxx_rtc_ops, THIS_MODULE); @@ -253,9 +257,9 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) out_irq1: free_irq(rtc_data->irq_alarm, &pdev->dev); out_irq_alarm: - __mxs_clrl(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN | + writel(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN | STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, - rtc_data->io + STMP3XXX_RTC_CTRL); + rtc_data->io + STMP3XXX_RTC_CTRL_CLR); rtc_device_unregister(rtc_data->rtc); out_remap: platform_set_drvdata(pdev, NULL); @@ -276,10 +280,10 @@ static int stmp3xxx_rtc_resume(struct platform_device *dev) struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(dev); mxs_reset_block(rtc_data->io); - __mxs_clrl(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | + writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE, - rtc_data->io + STMP3XXX_RTC_PERSISTENT0); + rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR); return 0; } #else -- cgit v1.2.3-70-g09d2 From 7e794cb7e36ccdb8c44b8ca7738720625b7aa2da Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Wed, 25 May 2011 12:56:53 +0200 Subject: rtc: stmp3xxx: Remove UIE handlers The RTC core handles UIE since 6610e08 (RTC: Rework RTC code to use timerqueue for events), so remove the specific interrupt in this driver. To make it work at all, enable interrupts in set_alarm() if needed. Drop IRQF_DISABLED which is deprecated, while we are here. Finally, add my copyright after all these changes. Signed-off-by: Wolfram Sang Tested-by: Shawn Guo Signed-off-by: John Stultz --- drivers/rtc/rtc-stmp3xxx.c | 61 ++++++++++++++-------------------------------- 1 file changed, 18 insertions(+), 43 deletions(-) (limited to 'drivers/rtc') diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c index ad185179694..7315068daa5 100644 --- a/drivers/rtc/rtc-stmp3xxx.c +++ b/drivers/rtc/rtc-stmp3xxx.c @@ -6,6 +6,7 @@ * * Copyright 2008 Freescale Semiconductor, Inc. All Rights Reserved. * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved. + * Copyright 2011 Wolfram Sang, Pengutronix e.K. */ /* @@ -33,7 +34,6 @@ #define STMP3XXX_RTC_CTRL_ALARM_IRQ_EN 0x00000001 #define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN 0x00000002 #define STMP3XXX_RTC_CTRL_ALARM_IRQ 0x00000004 -#define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ 0x00000008 #define STMP3XXX_RTC_STAT 0x10 #define STMP3XXX_RTC_STAT_STALE_SHIFT 16 @@ -52,9 +52,8 @@ struct stmp3xxx_rtc_data { struct rtc_device *rtc; - unsigned irq_count; void __iomem *io; - int irq_alarm, irq_1msec; + int irq_alarm; }; static void stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data) @@ -92,32 +91,16 @@ static int stmp3xxx_rtc_set_mmss(struct device *dev, unsigned long t) static irqreturn_t stmp3xxx_rtc_interrupt(int irq, void *dev_id) { struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev_id); - u32 status; - u32 events = 0; - - status = readl(rtc_data->io + STMP3XXX_RTC_CTRL) & - (STMP3XXX_RTC_CTRL_ALARM_IRQ | - STMP3XXX_RTC_CTRL_ONEMSEC_IRQ); + u32 status = readl(rtc_data->io + STMP3XXX_RTC_CTRL); if (status & STMP3XXX_RTC_CTRL_ALARM_IRQ) { writel(STMP3XXX_RTC_CTRL_ALARM_IRQ, rtc_data->io + STMP3XXX_RTC_CTRL_CLR); - events |= RTC_AF | RTC_IRQF; + rtc_update_irq(rtc_data->rtc, 1, RTC_AF | RTC_IRQF); + return IRQ_HANDLED; } - if (status & STMP3XXX_RTC_CTRL_ONEMSEC_IRQ) { - writel(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ, - rtc_data->io + STMP3XXX_RTC_CTRL_CLR); - if (++rtc_data->irq_count % 1000 == 0) { - events |= RTC_UF | RTC_IRQF; - rtc_data->irq_count = 0; - } - } - - if (events) - rtc_update_irq(rtc_data->rtc, 1, events); - - return IRQ_HANDLED; + return IRQ_NONE; } static int stmp3xxx_alarm_irq_enable(struct device *dev, unsigned int enabled) @@ -155,6 +138,9 @@ static int stmp3xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) rtc_tm_to_time(&alm->time, &t); writel(t, rtc_data->io + STMP3XXX_RTC_ALARM); + + stmp3xxx_alarm_irq_enable(dev, alm->enabled); + return 0; } @@ -174,11 +160,9 @@ static int stmp3xxx_rtc_remove(struct platform_device *pdev) if (!rtc_data) return 0; - writel(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN | - STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, + writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, rtc_data->io + STMP3XXX_RTC_CTRL_CLR); free_irq(rtc_data->irq_alarm, &pdev->dev); - free_irq(rtc_data->irq_1msec, &pdev->dev); rtc_device_unregister(rtc_data->rtc); platform_set_drvdata(pdev, NULL); iounmap(rtc_data->io); @@ -212,7 +196,6 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) } rtc_data->irq_alarm = platform_get_irq(pdev, 0); - rtc_data->irq_1msec = platform_get_irq(pdev, 1); if (!(readl(STMP3XXX_RTC_STAT + rtc_data->io) & STMP3XXX_RTC_STAT_RTC_PRESENT)) { @@ -229,6 +212,10 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE, rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR); + writel(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN | + STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, + rtc_data->io + STMP3XXX_RTC_CTRL_CLR); + rtc_data->rtc = rtc_device_register(pdev->name, &pdev->dev, &stmp3xxx_rtc_ops, THIS_MODULE); if (IS_ERR(rtc_data->rtc)) { @@ -236,30 +223,17 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) goto out_remap; } - rtc_data->irq_count = 0; - err = request_irq(rtc_data->irq_alarm, stmp3xxx_rtc_interrupt, - IRQF_DISABLED, "RTC alarm", &pdev->dev); + err = request_irq(rtc_data->irq_alarm, stmp3xxx_rtc_interrupt, 0, + "RTC alarm", &pdev->dev); if (err) { dev_err(&pdev->dev, "Cannot claim IRQ%d\n", rtc_data->irq_alarm); goto out_irq_alarm; } - err = request_irq(rtc_data->irq_1msec, stmp3xxx_rtc_interrupt, - IRQF_DISABLED, "RTC tick", &pdev->dev); - if (err) { - dev_err(&pdev->dev, "Cannot claim IRQ%d\n", - rtc_data->irq_1msec); - goto out_irq1; - } return 0; -out_irq1: - free_irq(rtc_data->irq_alarm, &pdev->dev); out_irq_alarm: - writel(STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN | - STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, - rtc_data->io + STMP3XXX_RTC_CTRL_CLR); rtc_device_unregister(rtc_data->rtc); out_remap: platform_set_drvdata(pdev, NULL); @@ -316,5 +290,6 @@ module_init(stmp3xxx_rtc_init); module_exit(stmp3xxx_rtc_exit); MODULE_DESCRIPTION("STMP3xxx RTC Driver"); -MODULE_AUTHOR("dmitry pervushin "); +MODULE_AUTHOR("dmitry pervushin and " + "Wolfram Sang "); MODULE_LICENSE("GPL"); -- cgit v1.2.3-70-g09d2