On Thursday, September 15, 2011 03:43:42 AM Jason Hui wrote:
On Thu, Sep 15, 2011 at 3:39 AM, Marek Vasut marek.vasut@gmail.com wrote:
On Friday, July 29, 2011 08:55:14 AM Jason Hui wrote:
Hi, Marek,
On Thu, Jul 14, 2011 at 5:58 AM, Marek Vasut marek.vasut@gmail.com wrote:
Rewrite the mxc_i2c driver.
- This version is much closer to Linux implementation.
- Fixes IPG_PERCLK being incorrectly used as clock source
- Fixes behaviour of the driver on iMX51
- Clean up coding style a bit ;-)
why you change i2c clock from IPG_PERCLK to IPG_CLK?
[...]
Ok, I investigated a bit deeper and I suspect the clock.c is the culprit.
Apparently, the PERCLK doesn't run at the frequency the clock.c reports it runs on. Therefore, the i2c miscalculates the divider etc -- falling crap model (waterfall model).
But apparently, the i2c function clock should be IPG_PERCLK not IPG clock. And Linux also fix it already.
Then there's bulls**t in your mx51 and mx53 datasheet or what ? besides, PERCLK is faster than IPGCLK on MX51 so it makes even less sense! Can you please talk to the HW guys or whatever to clear this once and for all ? I smell noone really knows where the clock are sourced from and all this crap is just blind guessing.