Hi Andrew, > -----Original Message----- > From: Andrew Jeffery <and...@aj.id.au> > Sent: Tuesday, December 15, 2020 8:12 AM > To: ChiaWei Wang <chiawei_w...@aspeedtech.com>; Rob Herring > <robh...@kernel.org>; Joel Stanley <j...@jms.id.au> > Cc: Ryan Chen <ryan_c...@aspeedtech.com>; Lee Jones > <lee.jo...@linaro.org>; Corey Minyard <miny...@acm.org>; Arnd Bergmann > <a...@arndb.de>; Greg Kroah-Hartman <gre...@linuxfoundation.org>; Linus > Walleij <linus.wall...@linaro.org>; Haiyue Wang > <haiyue.w...@linux.intel.com>; linux-arm-ker...@lists.infradead.org; > linux-asp...@lists.ozlabs.org; linux-kernel@vger.kernel.org; > open...@lists.ozlabs.org; linux-g...@vger.kernel.org > Subject: Re: [PATCH v2 5/5] dt-bindings: aspeed-lpc: Remove LPC partitioning > > Hi Chiawei, > > On Mon, 14 Dec 2020, at 13:14, ChiaWei Wang wrote: > > Hi Andrew & Rob, > > > > Do you have any suggestion on this patch? > > Rob hasn't responded, but I think it will be easier to get an Ack out of him > if we > do a v2 of the binding so we're not breaking backwards-compatibility with the > current definition. Concretely: > > - compatible: One of: > "aspeed,ast2400-lpc", "simple-mfd" > "aspeed,ast2500-lpc", "simple-mfd" > > Becomes something like: > > - compatible: One of: > "aspeed,ast2400-lpc-v2", "simple-mfd" > "aspeed,ast2500-lpc-v2", "simple-mfd" > > We can convert the in-tree devicetrees, immediately drop support for the > current binding in the drivers, and _only_ support v2 of the binding going > forward. That way your patches stay largely the same, the binding isn't > hamstrung as it is currently, and we're not trying to maintain code to support > the current binding definition - but we're also not pretending that old > devicetrees will work with newer kernels that only support the new binding > definition (which is the problem with your current patch series). > > How does that sound? Sounds good. The v2 binding string should be a notification to sync both the new device tree and the new drivers. I will prepare a v3 patch with this change and the commit reordering suggested.
Thanks, Chiawei > > As to how to implement this, I think we'll need to add some > of_device_is_compatible() checks in the relevant drivers to make sure that > they're using the new LPC binding, such as in > drivers/pinctrl/aspeed/pinctrl-aspeed-g5.c before we fetch the regmap on line > 2657. > > Sorry that this is dragging out a bit (and for the mess I made). > > Cheers, > > Andrew