[PATCH] rtc: snvs: improve timeout handling in snvs_rtc_enable()
From: Shawn Guo <hidden>
Date: 2012-08-18 12:46:54
On Sat, Aug 18, 2012 at 10:10:08AM +0200, Lothar Wa?mann wrote:
If snvs_rtc_enable() happens to be descheduled for a period longer than the timout period, a timeout may be indicated even if the RTC status has changed meanwhile. Force a status read at the end of the timeout period to prevent bogus timeout errors. Signed-off-by: Lothar Wa?mann <redacted> --- drivers/rtc/rtc-snvs.c | 22 +++++++++++++--------- 1 files changed, 13 insertions(+), 9 deletions(-) Compile tested only due to lack of HW.
Tested-by: Shawn Guo <redacted> A small nitpick below.
quoted hunk ↗ jump to hunk
diff --git a/drivers/rtc/rtc-snvs.c b/drivers/rtc/rtc-snvs.c index 912f116..dc921b2 100644 --- a/drivers/rtc/rtc-snvs.c +++ b/drivers/rtc/rtc-snvs.c@@ -81,6 +81,13 @@ static void rtc_write_sync_lp(void __iomem *ioaddr) } } +static int snvs_rtc_enable_done(int enable, void __iomem *addr)
Can we rename parameter "addr" to "ioaddr" and put it before "enable", also change "enable" to bool? Regards, Shawn
quoted hunk ↗ jump to hunk
+{ + u32 lpcr = readl(addr + SNVS_LPCR); + + return !!enable ^ !(lpcr & SNVS_LPCR_SRTC_ENV); +} + static int snvs_rtc_enable(struct snvs_rtc_data *data, bool enable) { unsigned long timeout = jiffies + msecs_to_jiffies(1);@@ -99,18 +106,15 @@ static int snvs_rtc_enable(struct snvs_rtc_data *data, bool enable) spin_unlock_irqrestore(&data->lock, flags); while (1) { - lpcr = readl(data->ioaddr + SNVS_LPCR); + if (snvs_rtc_enable_done(enable, data->ioaddr)) + break; - if (enable) { - if (lpcr & SNVS_LPCR_SRTC_ENV) - break; - } else { - if (!(lpcr & SNVS_LPCR_SRTC_ENV)) + if (time_after(jiffies, timeout)) { + if (snvs_rtc_enable_done(enable, data->ioaddr)) break; + else + return -ETIMEDOUT; } - - if (time_after(jiffies, timeout)) - return -ETIMEDOUT; } return 0;-- 1.7.2.5