Add DS1341 specific power-saving options that allow to disable certain functional aspects of the chip in order to minimize its power consumption.
Signed-off-by: Andrey Smirnov <[email protected]> --- .../devicetree/bindings/rtc/dallas,ds1341.txt | 23 ++++++++++++++++++ drivers/rtc/rtc-ds1307.c | 28 ++++++++++++++++++++++ 2 files changed, 51 insertions(+) create mode 100644 Documentation/devicetree/bindings/rtc/dallas,ds1341.txt diff --git a/Documentation/devicetree/bindings/rtc/dallas,ds1341.txt b/Documentation/devicetree/bindings/rtc/dallas,ds1341.txt new file mode 100644 index 0000000..b8be7a4 --- /dev/null +++ b/Documentation/devicetree/bindings/rtc/dallas,ds1341.txt @@ -0,0 +1,23 @@ +* Dallas DS1341 I2C Serial Real-Time Clock + +Required properties: + +- compatible: Should contain "dallas,ds1341". + +- reg: I2C address for chip + +Optional properties: + +- disable-oscillator-stop-flag : Configure chip to disable oscillator + fault detection circuitry + +- enable-glitch-filter : Configure chip to enable crystal oscillator + output glitch filtering + +Example: + ds1341: rtc@68 { + compatible = "dallas,ds1341"; + disable-oscillator-stop-flag; + enable-glitch-filter; + reg = <0x68>; + }; diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c index c618c22..54cc527 100644 --- a/drivers/rtc/rtc-ds1307.c +++ b/drivers/rtc/rtc-ds1307.c @@ -78,6 +78,7 @@ enum ds_type { #define DS1337_REG_CONTROL 0x0e # define DS1337_BIT_nEOSC 0x80 # define DS1339_BIT_BBSQI 0x20 +# define DS1341_BIT_EGFIL 0x20 # define DS3231_BIT_BBSQW 0x40 /* same as BBSQI */ # define DS1337_BIT_RS2 0x10 # define DS1337_BIT_RS1 0x08 @@ -93,7 +94,9 @@ enum ds_type { # define DS1340_BIT_OSF 0x80 #define DS1337_REG_STATUS 0x0f # define DS1337_BIT_OSF 0x80 +# define DS1341_BIT_DOSF 0x40 # define DS3231_BIT_EN32KHZ 0x08 +# define DS1341_BIT_ECLK 0x04 # define DS1337_BIT_A2I 0x02 # define DS1337_BIT_A1I 0x01 #define DS1339_REG_ALARM1_SECS 0x07 @@ -1319,6 +1322,31 @@ static int ds1307_probe(struct i2c_client *client, if (ds1307->regs[0] & DS1337_BIT_nEOSC) ds1307->regs[0] &= ~DS1337_BIT_nEOSC; + if (ds1307->type == ds_1341) { + /* Make sure we are not generating square wave + * output */ + ds1307->regs[1] &= ~DS1341_BIT_ECLK; + + if (of_property_read_bool(client->dev.of_node, + "disable-oscillator-stop-flag")) + ds1307->regs[1] |= DS1341_BIT_DOSF; + else + ds1307->regs[1] &= ~DS1341_BIT_DOSF; + + if (of_property_read_bool(client->dev.of_node, + "enable-glitch-filter")) + ds1307->regs[0] |= DS1341_BIT_EGFIL; + else + ds1307->regs[0] &= ~DS1341_BIT_EGFIL; + + /* + * Write status register. Control register + * would be set by the code below + */ + i2c_smbus_write_byte_data(client, DS1337_REG_STATUS, + ds1307->regs[1]); + } + /* * Disable the square wave and both alarms. * For some variants, be sure alarms can trigger when we're -- 2.5.5
