From mboxrd@z Thu Jan 1 00:00:00 1970 From: Frank Rowand Subject: Re: [PATCH v1 0/5] Solve postboot supplier cleanup and optimize probe ordering Date: Fri, 24 May 2019 17:22:47 -0700 Message-ID: <6d3995c1-e1e7-35ff-d091-501822c97ecd@gmail.com> References: <20190524010117.225219-1-saravanak@google.com> <06b479e2-e8a0-b3e8-567c-7fa0f1c5bdf6@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Saravana Kannan Cc: Rob Herring , Mark Rutland , Greg Kroah-Hartman , "Rafael J. Wysocki" , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Android Kernel Team List-Id: devicetree@vger.kernel.org On 5/24/19 2:53 PM, Saravana Kannan wrote: > On Fri, May 24, 2019 at 10:49 AM Frank Rowand wrote: >> >> On 5/23/19 6:01 PM, Saravana Kannan wrote: < snip > >> Another flaw with this method is that existing device trees >> will be broken after the kernel is modified, because existing >> device trees do not have the depends-on property. This breaks >> the devicetree compatibility rules. > > This is 100% not true with the current implementation. I actually > tested this. This is fully backwards compatible. That's another reason > for adding depends-on and going by just what it says. The existing > bindings were never meant to describe only mandatory dependencies. So > using them as such is what would break backwards compatibility. Are you saying that an existing, already compiled, devicetree (an FDT) can be used to boot a new kernel that has implemented this patch set? The new kernel will boot with the existing FDT that does not have any depends-on properties? -Frank