From 4ac24b3ba9016881b11646114bb5cd12cf23edd9 Mon Sep 17 00:00:00 2001 From: kogiidena Date: Thu, 10 May 2007 22:22:57 -0700 Subject: [PATCH] rtc-rs5c313.c: add error handling to avoid hardware hangup Add error processing. Hanging up by an infinite loop is evaded. Signed-off-by: kogiidena Cc: Alessandro Zummo Cc: David Brownell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rtc/rtc-rs5c313.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/drivers/rtc/rtc-rs5c313.c b/drivers/rtc/rtc-rs5c313.c index f964d1d..66eb133 100644 --- a/drivers/rtc/rtc-rs5c313.c +++ b/drivers/rtc/rtc-rs5c313.c @@ -212,7 +212,9 @@ static inline void rs5c313_write_intintvreg(unsigned char data) static int rs5c313_rtc_read_time(struct device *dev, struct rtc_time *tm) { int data; + int cnt; + cnt = 0; while (1) { RS5C313_CEENABLE; /* CE:H */ @@ -225,6 +227,10 @@ static int rs5c313_rtc_read_time(struct device *dev, struct rtc_time *tm) RS5C313_CEDISABLE; ndelay(700); /* CE:L */ + if (cnt++ > 100) { + dev_err(dev, "%s: timeout error\n", __FUNCTION__); + return -EIO; + } } data = rs5c313_read_reg(RS5C313_ADDR_SEC); @@ -266,7 +272,9 @@ static int rs5c313_rtc_read_time(struct device *dev, struct rtc_time *tm) static int rs5c313_rtc_set_time(struct device *dev, struct rtc_time *tm) { int data; + int cnt; + cnt = 0; /* busy check. */ while (1) { RS5C313_CEENABLE; /* CE:H */ @@ -279,6 +287,11 @@ static int rs5c313_rtc_set_time(struct device *dev, struct rtc_time *tm) RS5C313_MISCOP; RS5C313_CEDISABLE; ndelay(700); /* CE:L */ + + if (cnt++ > 100) { + dev_err(dev, "%s: timeout error\n", __FUNCTION__); + return -EIO; + } } data = BIN2BCD(tm->tm_sec); @@ -317,6 +330,7 @@ static int rs5c313_rtc_set_time(struct device *dev, struct rtc_time *tm) static void rs5c313_check_xstp_bit(void) { struct rtc_time tm; + int cnt; RS5C313_CEENABLE; /* CE:H */ if (rs5c313_read_cntreg() & RS5C313_CNTREG_WTEN_XSTP) { @@ -326,8 +340,11 @@ static void rs5c313_check_xstp_bit(void) rs5c313_write_cntreg(0x07); /* busy check. */ - while (rs5c313_read_cntreg() & RS5C313_CNTREG_ADJ_BSY) + for (cnt = 0; cnt < 100; cnt++) { + if (!(rs5c313_read_cntreg() & RS5C313_CNTREG_ADJ_BSY)) + break; RS5C313_MISCOP; + } memset(&tm, 0, sizeof(struct rtc_time)); tm.tm_mday = 1; -- 2.7.4