2009-03-17 02:57:38     SCCB(I2C) driver on GPIO not working

2009-03-17 02:57:38     SCCB(I2C) driver on GPIO not working

andy (UNITED STATES)

Message: 71072   

I had emulated SCCB (I2C) interface to a camera module on gpio pins in the 2006 uclinux release. I was using the pflags gpio device interface.

When I try running the same emulation code on the new kernel it fails to communicate with the module. I did make the necessary changes on the gpio front i.e. using the simple-gpio driver now. I have checked the gpio seperately and it works.

The SCCB code has a lot of timing sensitive code. Could it be that the previous pflags gpio interface and simple-gpio interface take different amount to time and hence is messing up the SCCB interface?

thanks.

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2009-03-17 04:16:21     SCCB(I2C) driver on GPIO not working

Michael Hennerich (GERMANY)

Message: 71084   

Andy,

What you describe is a No-Go.

Use the kernel level gpio-based bitbang i2c driver

in conjunction with the user space i2c device interface.

There are some examples in

uclinux-dist/user/blkfin-test/ppifcd-test/i2c.c

-Michael