On Wed, Mar 09, 2022 at 10:01:23PM +0300, Serge Semin wrote: [...] > > I'm afraid that this will not work for all cases (unless I miss something). As > > Zhi Li pointed out, there are places where only chip pointer will be passed and > > we'd need to extract the private data (dw_edma) from it. > > > > Tbh I also considered your idea but because of the above mentioned issue and > > also referring to other implementations like gpiochip, I settled with Frank's > > idea of copying the fields. > > What places are these? I see the only obstacle is the dw_edma_remove() > method. But it's easily fixable. Yeah, right. I overlooked that part. > Except that, everything else is more > or less straightforward (just a few methods need to have prototypes > converted to accepting dw_edma instead dw_edma_chip). > > In order to make the code design more coherent, we need to split up > private data and device/platform info. As I see it dw_edma_chip is > nothing but a chip info data. The eDMA driver is supposed to mainly > use and pass it's private data, not the platform info. It will greatly > improve the code readability and maintainability. Such approach will > also prevent a temptation of adding new private data fields into the > dw_edma_chip structure since reaching the pointer to dw_edma will be > much easier that getting the dw_edma_chip data. In this case > dw_edma_chip will be something like i2c_board_info in i2c. > > Ideally dw_edma_chip could be a temporarily defined device info, which > memory after the dw_edma_probe() method invocation could be freed. But > in order to implement that we'd need a bit more modifications > introduced. > While at it, we should also consider adding an ops structure for passing the callbacks from controller drivers. Currently the eDMA driver has the callbacks defined in v0-core.c but it is used directly instead of as a callback. This should anyway needs to be fixed when another version of the IP get's added. Thanks, Mani
