From ee087744247c421c83abea7f01217bfd39b8f5a9 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Myl=C3=A8ne=20Josserand?= Date: Mon, 21 Mar 2016 18:06:10 +0100 Subject: rtc: abx80x: handle the oscillator failure bit MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Handle the Oscillator Failure ('OF') bit from Oscillator Status register (0x1D). This bit is cleared on set_time function and is read each time the date/time is read, but only in case of XT Oscillator selection. In RC mode, this bit is always set. Signed-off-by: Mylène Josserand Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-abx80x.c | 33 +++++++++++++++++++++++++++++++-- 1 file changed, 31 insertions(+), 2 deletions(-) (limited to 'drivers/rtc') diff --git a/drivers/rtc/rtc-abx80x.c b/drivers/rtc/rtc-abx80x.c index 0e4c9a0989d1..ba0d61934d35 100644 --- a/drivers/rtc/rtc-abx80x.c +++ b/drivers/rtc/rtc-abx80x.c @@ -58,6 +58,7 @@ #define ABX8XX_OSC_OSEL BIT(7) #define ABX8XX_REG_OSS 0x1d +#define ABX8XX_OSS_OF BIT(1) #define ABX8XX_OSS_OMODE BIT(4) #define ABX8XX_REG_CFG_KEY 0x1f @@ -138,7 +139,23 @@ static int abx80x_rtc_read_time(struct device *dev, struct rtc_time *tm) { struct i2c_client *client = to_i2c_client(dev); unsigned char buf[8]; - int err; + int err, flags, rc_mode = 0; + + /* Read the Oscillator Failure only in XT mode */ + rc_mode = abx80x_is_rc_mode(client); + if (rc_mode < 0) + return rc_mode; + + if (!rc_mode) { + flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS); + if (flags < 0) + return flags; + + if (flags & ABX8XX_OSS_OF) { + dev_err(dev, "Oscillator failure, data is invalid.\n"); + return -EINVAL; + } + } err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_HTH, sizeof(buf), buf); @@ -166,7 +183,7 @@ static int abx80x_rtc_set_time(struct device *dev, struct rtc_time *tm) { struct i2c_client *client = to_i2c_client(dev); unsigned char buf[8]; - int err; + int err, flags; if (tm->tm_year < 100) return -EINVAL; @@ -187,6 +204,18 @@ static int abx80x_rtc_set_time(struct device *dev, struct rtc_time *tm) return -EIO; } + /* Clear the OF bit of Oscillator Status Register */ + flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS); + if (flags < 0) + return flags; + + err = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSS, + flags & ~ABX8XX_OSS_OF); + if (err < 0) { + dev_err(&client->dev, "Unable to write oscillator status register\n"); + return err; + } + return 0; } -- cgit v1.2.3