On Thu, Mar 14, 2013 at 09:53:55AM +0100, Marc Kleine-Budde wrote: > On 03/14/2013 09:34 AM, Peter Chen wrote: > > Hi Alex and all, > > > > Currently, we have two problems to block chipidea driver coming > > development. > > > > As there are so many chipidea versions, we impossible to collect > > all to make a decision, it is better to cover most of the cases, > > and using device tree (or platform data) to cover exceptions > > if they exist. > > > > 1. USB Mode Problem > > How can we decide USB mode (gadget, host and otg) at driver, and > > how to read OTGSC register? Below is my pinion. > > > > - We get gadget or host support from CAP_DCCPARAMS(DCCPARAMS_DC or DCCPARAMS_HC), > > IIRC This is broken on mx25. The host only port gets into an error state > if you read this register. :( If there is an exception, you can use DT to override it. Eg: if (ci->dccparams_is_error) do not read DCCPARAMS; /* using DT dr_mode setting */ > > There is a core on mips which doesn't support otg. From my point of > view, support for dual_role should be a separate patch, ideally by > Svetoslav (Cc'ed) who has this hardware, after we've cleaned up all > dr-mode related stuff. What means support OTG? The spec said it or there is a port DCCPARAMS_DC =1 but DCCPARAMS_HC = 0? >From my point, I still think if DCCPARAMS_DC = 1, it is save to read OTGSC. -- Best Regards, Peter Chen -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
