The 104-quad-8 driver was initially introduced to the IIO subsystem where it didn't quite fit with the existing paradigm [0]; these differences eventually led to the creation of the Counter subsystem[1]. As a result of its awkward beginnings, the design of the 104-quad-8 driver was structured around maintaining abstract state buffers that would eventually be converted to match the actual device registers states on-the-fly as needed. The original design approach for the 104-quad-8 driver was neither efficient nor easy to troubleshoot, but it did allow us to focus on implementing and supporting necessary APIs for the nascent Counter subsystem. Now that development for the 104-quad-8 driver has shifted to maintenance, it is a good time to refactor and clean up the code to match closer to what is actually happening on the device. This patchset is an attempt to rectify the situation as such. The primary change is a transition from maintaining individual configuration states independently, to storing buffers of the device register configurations. To that end, the bitfield API is leveraged to access and retrieve field states. Modifying bitfields is a common code pattern so a FIELD_MODIFY macro is introduced to facililate such. Finally some helper functions are introduced to abstract the handling of the PR, FLAG, and PSC registers. Modifying a buffer state in-place is a common pattern, so should we also consider adding a field_replace() function similar to bitmap_replace()? [0] https://lore.kernel.org/r/b43e2942b763b87afc85bfa9fe36e5695cba4c44.1475079578.git.vilhelm.gray@xxxxxxxxx/ [1] https://lore.kernel.org/r/cover.1554184734.git.vilhelm.gray@xxxxxxxxx/ William Breathitt Gray (4): counter: 104-quad-8: Utilize bitfield access macros bitfield: Introduce the FIELD_MODIFY() macro counter: 104-quad-8: Refactor to buffer states for CMR, IOR, and IDR counter: 104-quad-8: Utilize helper functions to handle PR, FLAG and PSC drivers/counter/104-quad-8.c | 526 ++++++++++++++++++----------------- include/linux/bitfield.h | 18 +- 2 files changed, 283 insertions(+), 261 deletions(-) base-commit: 00f4bc5184c19cb33f468f1ea409d70d19f8f502 -- 2.39.2
