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P1010 & I2C RTC DS1339

Question asked by yensid on Jul 22, 2014
Latest reply on Jul 25, 2014 by yensid

I'm using a custom PCB that is designed after the P1010RDB, with SDKv1.5. I'm trying to use the Maxim DS1339 RTC with this system.  The rtc-ds1307 driver that is in the kernel supports the chip.  I modified the dts file for the different chip and made the modifications to the defconfig noted below, however the probe function of the rtc-ds1307 driver is never called and the RTC cannot be accessed from Linux.  It was my understanding that after modifying the dts and enabling the driver the kernel would know that hardware was present and call the probe function for the driver.  Is that how this is suppose to work?  Any help is appreciated.

 

-The rtc itself can be set and read through U-Boot and works fine, I just can't access it from Linux

-Debug info was added to the probe function of the rtc-ds1307 driver and it is not displayed

-On the P1010RDB that I have, the RTC is not accessable through Linux either leading me to believe there is a configuration issue for the P1010RDB with SDK1.5

-I don't see any messages during boot about I2c or about loading the driver

 

-DTS Chages

I also tried "dallas, ds1307", which was unsuccessful

&board_soc {

  i2c@3000 {

  rtc@68 {

  compatible = "dallas,rtc-ds1307";

  reg = <0x68>;

  };

  };

...

-defconfig changes

CONFIG_I2C=y

CONFIG_RTC_LIB=y

CONFIG_RTC_CLASS=y

CONFIG_RTC_HCTOSYS=y

CONFIG_RTC_HCTOSYS_DEVICE="rtc0"

 

CONFIG_RTC_INTF_SYSFS=y

CONFIG_RTC_INTF_PROC=y

CONFIG_RTC_INTF_DEV=y

 

CONFIG_RTC_DRV_CMOS=y

CONFIG_RTC_DRV_DS1307=y

 

Thanks for your help! If I have missed something simple please let me know as I'm still a newbie.

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