> -----Original Message----- > From: Greg KH [mailto:gre...@linuxfoundation.org] > Sent: Wednesday, March 21, 2018 15:05 > To: Nipun Gupta <nipun.gu...@nxp.com> > Cc: robin.mur...@arm.com; h...@lst.de; li...@armlinux.org.uk; > m.szyprow...@samsung.com; bhelg...@google.com; zaj...@gmail.com; > andy.gr...@linaro.org; david.br...@linaro.org; dan.j.willi...@intel.com; > vinod.k...@intel.com; thierry.red...@gmail.com; robh...@kernel.org; > frowand.l...@gmail.com; jarkko.sakki...@linux.intel.com; > rafael.j.wyso...@intel.com; dmitry.torok...@gmail.com; jo...@kernel.org; > msucha...@suse.de; linux-ker...@vger.kernel.org; iommu@lists.linux- > foundation.org; linux-wireless@vger.kernel.org; linux-arm- > m...@vger.kernel.org; linux-...@vger.kernel.org; dmaeng...@vger.kernel.org; > dri-de...@lists.freedesktop.org; linux-te...@vger.kernel.org; > devicet...@vger.kernel.org; linux-...@vger.kernel.org; Bharat Bhushan > <bharat.bhus...@nxp.com>; Leo Li <leoyang...@nxp.com> > Subject: Re: [PATCH v2 2/2] drivers: remove force dma flag from buses > > On Wed, Mar 21, 2018 at 12:25:23PM +0530, Nipun Gupta wrote: > > With each bus implementing its own DMA configuration callback, > > there is no need for bus to explicitly have force_dma in its > > global structure. This patch modifies of_dma_configure API to > > accept an input parameter which specifies if implicit DMA > > configuration is required even when it is not described by the > > firmware. > > Having to "remember" what that bool variable means on the end of the > function call is a royal pain over time, right? > > Why not just create a new function: > dma_common_configure_force(dma) > that always does this? Leave "dma_common_configure()" alone, and then > wrap the old code with these two helper functions that call the 'core' > code with the bool set properly? > > That way you do not have to "know" what that parameter is, the function > name just documents it automatically, so when you see it in the > bus-specific code, no need to go and have to hunt for anything. And if > you are reading the dma core code, it's obvious what is happening as the > functions are all right there.
How about we do not pass any flag in 'dma_common_configure()', and inside this API we pass "true" to 'of_dma_configure()'? I am saying this because currently both the busses (platform and AMBA) which uses 'dma_common_configure()' passes "true" value. If we create additional 'dma_common_configure_force()', then 'dma_common_configure()' will not be used anytime and will become redundant. If someday new busses come and they needs to use similar functionality which 'dma_common_configure()' provides, but with passing "false" to 'of_dma_configure()', then what you suggests of having two separate such API's will be more reasonable and can be implemented? Thanks, Nipun > > thanks, > > greg k-h
