Hi, Leonard > > On 2019-09-27 4:20 AM, Anson Huang wrote: > > >> On 2019-09-26 1:06 PM, Marco Felsch wrote: > > >>> On 19-09-26 08:03, Anson Huang wrote: > > >>>>> On 19-09-25 18:07, Anson Huang wrote: > > >>>>>> The SCU firmware does NOT always have return value stored in > > >>>>>> message header's function element even the API has response > > >>>>>> data, those special APIs are defined as void function in SCU > > >>>>>> firmware, so they should be treated as return success always. > > >>>>>> > > >>>>>> +static const struct imx_sc_rpc_msg whitelist[] = { > > >>>>>> + { .svc = IMX_SC_RPC_SVC_MISC, .func = > > >>>>> IMX_SC_MISC_FUNC_UNIQUE_ID }, > > >>>>>> + { .svc = IMX_SC_RPC_SVC_MISC, .func = > > >>>>>> +IMX_SC_MISC_FUNC_GET_BUTTON_STATUS }, }; > > >>>>> > > >>>>> Is this going to be extended in the near future? I see some > > >>>>> upcoming problems here if someone uses a different > > >>>>> scu-fw<->kernel combination as nxp would suggest. > > >>>> > > >>>> Could be, but I checked the current APIs, ONLY these 2 will be > > >>>> used in Linux kernel, so I ONLY add these 2 APIs for now. > > >>> > > >>> Okay. > > >>> > > >>>> However, after rethink, maybe we should add another imx_sc_rpc > > >>>> API for those special APIs? To avoid checking it for all the APIs > > >>>> called which > > >> may impact some performance. > > >>>> Still under discussion, if you have better idea, please advise, thanks! > > >> > > >> My suggestion is to refactor the code and add a new API for the > > >> this "no error value" convention. Internally they can call a common > > >> function with flags. > > > > > > If I understand your point correctly, that means the loop check of > > > whether the API is with "no error value" for every API still NOT be > > > skipped, it is just refactoring the code, right? > > > > There would be no "loop" anywhere: the responsibility would fall on > > the call to call the right RPC function. In the current layering > > scheme (drivers -> RPC -> > > mailbox) the RPC layer treats all calls the same and it's up the the > > caller to provide information about calling convention. > > > > An example implementation: > > * Rename imx_sc_rpc_call to __imx_sc_rpc_call_flags > > * Make a tiny imx_sc_rpc_call wrapper which just converts resp/noresp > > to a flag > > * Make get button status call __imx_sc_rpc_call_flags with the > > _IMX_SC_RPC_NOERROR flag > > > > Hope this makes my suggestion clearer? Pushing this to the caller is a > > bit ugly but I think it's worth preserving the fact that the imx rpc > > core treats services in an uniform way. > > It is clear now, so essentially it is same as 2 separate APIs, still need to > change > the button driver and uid driver to use the special flag, meanwhile, need to > change the third parament of imx_sc_rpc_call() from bool to u32.
Correct one thing, no need to change the parameter of imx_sc_rpc_call(), just add another API using the flag as parameter, and imx_sc_rpc_call() calls the new API. Anson > > If no one opposes this approach, I will redo the patch together with the > button driver and uid driver after holiday. > > Anson