Linux.com

Home Linux Community Forums Programming and Development Kernel Development need to upgrade kernel with driver- ISL1221 RTC

need to upgrade kernel with driver- ISL1221 RTC

Link to this post 17 Aug 10

Hi all

i m a beginner in device drivers.

I m using linux kernel 2-6-20 , which is for our application with AT91SAM9260 processor.

I would like to use an RTC to update my system time, the chip is RTC - ISL1221 from intersil.

This kernel is supporting ISL 1208 but not ISL 1221 . [ I could see few options in kernel configuration time, but ISL 1221 is not present in the device drivers-> real time clock -> RTC drivers list. ]


HOW CAN I CONFIGURE THIS KERNEL FOR THIS NEW RTC
, if i write a driver for this?

Please help me out

Regards

SJR

Link to this post 17 Aug 10

I don't know much myself in that area but this looks like a good place to start.

Link to this post 17 Aug 10

thanks for the reply


I could find a solution for this ....

I have added the new RTC configuration in /linux/drivers/rtc/Kconfig as shown below, and now i am able to configure the kernel with the new chip ISL 1221

<
config RTC_DRV_ISL1221
tristate "Intersil 1221"
depends on RTC_CLASS && I2C
help
If you say yes here you get support for the
Intersil 1221 RTC chip.
This driver can also be built as a module. If so, the module
will be called rtc-isl1221.
>

Hope now i can go ahead with the driver developement for RTC ISL 1221
Please correct me if I m doing any thing wrong ....

thanks in advance

SJR

Link to this post 17 Aug 10

<
config RTC_DRV_ISL1221
tristate "Intersil 1221"
depends on RTC_CLASS && I2C
help
If you say yes here you get support for the
Intersil 1221 RTC chip.
This driver can also be built as a module. If so, the module
will be called rtc-isl1221.
>

That makes no sense to me. You put all that in the config file?

Link to this post 17 Aug 10

yes ... i have changed the configuration file for rtc drivers ...............

do u have some thing more to share regarding this ??

Link to this post 18 Aug 10

You seem to be on the right track, by my understanding your modification should tell the RTC core to use your driver to communicate. But before that modification is made you will need to build the kernel driver, you can refer to the other drivers in /usr/src/linux/drivers/rtc for examples on working modules. Once the driver has been written and your Kconfig has been applied you will also need to build a custom kernel using your modified files before it will be detected by the running kernel.

Who we are ?

The Linux Foundation is a non-profit consortium dedicated to the growth of Linux.

More About the foundation...

Frequent Questions

Join / Linux Training / Board