From 498bcf313985c76c4572d8ce885a6480728d28f9 Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Fri, 16 Jun 2017 21:28:07 +0200 Subject: [PATCH] rtc: s3c: Handle clock enable failures clk_enable() can fail so handle such case. Signed-off-by: Krzysztof Kozlowski Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-s3c.c | 72 ++++++++++++++++++++++++++++++++++--------- 1 file changed, 57 insertions(+), 15 deletions(-) diff --git a/drivers/rtc/rtc-s3c.c b/drivers/rtc/rtc-s3c.c index 0cb2f27a30b4..a8992c227f61 100644 --- a/drivers/rtc/rtc-s3c.c +++ b/drivers/rtc/rtc-s3c.c @@ -68,18 +68,32 @@ struct s3c_rtc_data { void (*disable) (struct s3c_rtc *info); }; -static void s3c_rtc_enable_clk(struct s3c_rtc *info) +static int s3c_rtc_enable_clk(struct s3c_rtc *info) { unsigned long irq_flags; + int ret = 0; spin_lock_irqsave(&info->alarm_clk_lock, irq_flags); + if (info->clk_disabled) { - clk_enable(info->rtc_clk); - if (info->data->needs_src_clk) - clk_enable(info->rtc_src_clk); + ret = clk_enable(info->rtc_clk); + if (ret) + goto out; + + if (info->data->needs_src_clk) { + ret = clk_enable(info->rtc_src_clk); + if (ret) { + clk_disable(info->rtc_clk); + goto out; + } + } info->clk_disabled = false; } + +out: spin_unlock_irqrestore(&info->alarm_clk_lock, irq_flags); + + return ret; } static void s3c_rtc_disable_clk(struct s3c_rtc *info) @@ -122,10 +136,13 @@ static int s3c_rtc_setaie(struct device *dev, unsigned int enabled) { struct s3c_rtc *info = dev_get_drvdata(dev); unsigned int tmp; + int ret; dev_dbg(info->dev, "%s: aie=%d\n", __func__, enabled); - s3c_rtc_enable_clk(info); + ret = s3c_rtc_enable_clk(info); + if (ret) + return ret; tmp = readb(info->base + S3C2410_RTCALM) & ~S3C2410_RTCALM_ALMEN; @@ -136,10 +153,13 @@ static int s3c_rtc_setaie(struct device *dev, unsigned int enabled) s3c_rtc_disable_clk(info); - if (enabled) - s3c_rtc_enable_clk(info); - else + if (enabled) { + ret = s3c_rtc_enable_clk(info); + if (ret) + return ret; + } else { s3c_rtc_disable_clk(info); + } return 0; } @@ -147,10 +167,14 @@ static int s3c_rtc_setaie(struct device *dev, unsigned int enabled) /* Set RTC frequency */ static int s3c_rtc_setfreq(struct s3c_rtc *info, int freq) { + int ret; + if (!is_power_of_2(freq)) return -EINVAL; - s3c_rtc_enable_clk(info); + ret = s3c_rtc_enable_clk(info); + if (ret) + return ret; spin_lock_irq(&info->pie_lock); if (info->data->set_freq) @@ -167,8 +191,11 @@ static int s3c_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm) { struct s3c_rtc *info = dev_get_drvdata(dev); unsigned int have_retried = 0; + int ret; - s3c_rtc_enable_clk(info); + ret = s3c_rtc_enable_clk(info); + if (ret) + return ret; retry_get_time: rtc_tm->tm_min = readb(info->base + S3C2410_RTCMIN); @@ -212,6 +239,7 @@ static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm) { struct s3c_rtc *info = dev_get_drvdata(dev); int year = tm->tm_year - 100; + int ret; dev_dbg(dev, "set time %04d.%02d.%02d %02d:%02d:%02d\n", 1900 + tm->tm_year, tm->tm_mon, tm->tm_mday, @@ -224,7 +252,9 @@ static int s3c_rtc_settime(struct device *dev, struct rtc_time *tm) return -EINVAL; } - s3c_rtc_enable_clk(info); + ret = s3c_rtc_enable_clk(info); + if (ret) + return ret; writeb(bin2bcd(tm->tm_sec), info->base + S3C2410_RTCSEC); writeb(bin2bcd(tm->tm_min), info->base + S3C2410_RTCMIN); @@ -243,8 +273,11 @@ static int s3c_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm) struct s3c_rtc *info = dev_get_drvdata(dev); struct rtc_time *alm_tm = &alrm->time; unsigned int alm_en; + int ret; - s3c_rtc_enable_clk(info); + ret = s3c_rtc_enable_clk(info); + if (ret) + return ret; alm_tm->tm_sec = readb(info->base + S3C2410_ALMSEC); alm_tm->tm_min = readb(info->base + S3C2410_ALMMIN); @@ -293,6 +326,7 @@ static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm) struct s3c_rtc *info = dev_get_drvdata(dev); struct rtc_time *tm = &alrm->time; unsigned int alrm_en; + int ret; int year = tm->tm_year - 100; dev_dbg(dev, "s3c_rtc_setalarm: %d, %04d.%02d.%02d %02d:%02d:%02d\n", @@ -300,7 +334,9 @@ static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm) 1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec); - s3c_rtc_enable_clk(info); + ret = s3c_rtc_enable_clk(info); + if (ret) + return ret; alrm_en = readb(info->base + S3C2410_RTCALM) & S3C2410_RTCALM_ALMEN; writeb(0x00, info->base + S3C2410_RTCALM); @@ -349,8 +385,11 @@ static int s3c_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm) static int s3c_rtc_proc(struct device *dev, struct seq_file *seq) { struct s3c_rtc *info = dev_get_drvdata(dev); + int ret; - s3c_rtc_enable_clk(info); + ret = s3c_rtc_enable_clk(info); + if (ret) + return ret; if (info->data->enable_tick) info->data->enable_tick(info, seq); @@ -589,8 +628,11 @@ static int s3c_rtc_probe(struct platform_device *pdev) static int s3c_rtc_suspend(struct device *dev) { struct s3c_rtc *info = dev_get_drvdata(dev); + int ret; - s3c_rtc_enable_clk(info); + ret = s3c_rtc_enable_clk(info); + if (ret) + return ret; /* save TICNT for anyone using periodic interrupts */ if (info->data->save_tick_cnt)