Re: [U-Boot] [PATCH] mxs: i2c: Implement algorithm to set up arbitrary i2c speed

Dear Marek Vasut,

In message 1354280910-17539-1-git-send-email-marex@denx.de you wrote:

This algorithm computes the values of TIMING{0,1,2} registers for the MX28 I2C block. This algorithm was derived by using a scope, but the result seems correct.

Thanks! I like that!

...

• uint32_t base = ((24000000 / speed) - 38) / 2;

...

• return 24000000 / ((((timing0 >> 16) - 3) * 2) + 38);

But we should get rid of this magic constant. On other i.MX systems that would probably be MXC_HCLK ?

For iMX28, we have CONFIG_PL011_CLOCK in the board config files instead.

Hm... grepping the source tree for 24000000 I get the feeling that this really needs some cleanup....

Best regards,

Wolfgang Denk