From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Subject: Re: [PATCH 08/10] dt/bindings: Add binding for BCM2835 mailbox property channel driver Date: Tue, 03 Mar 2015 20:53:50 -0700 Message-ID: <54F681CE.2070801@wwwdotorg.org> References: <1425329684-23968-1-git-send-email-eric@anholt.net> <1425329684-23968-9-git-send-email-eric@anholt.net> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1425329684-23968-9-git-send-email-eric-WhKQ6XTQaPysTnJN9+BGXg@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Eric Anholt Cc: linux-rpi-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Lee Jones , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Jassi Brar , Craig McGeachie , Lubomir Rintel List-Id: devicetree@vger.kernel.org On 03/02/2015 01:54 PM, Eric Anholt wrote: > I was tempted to have the mailbox property channel support just be in > the 2835 mailbox driver itself, but mbox_request_channel() wants its > device to have the "mboxes" node, and that appears to be only intended > for mailbox clients, not controllers. This is more of a particular format/protocol of messages you can send over the mailbox HW than a device. I wonder if it actually makes sense to represent it in DT as a device at all? If we do represent this as a device in DT, shouldn't it also look like a mailbox device so that other drivers (clock, display, ...) can bind to it and send messages using the mailbox API? I might have expected to just add property support directly into the basic bcm2835 mailbox driver itself. Perhaps some attempt might be made to isolate the HW register level access in one file/driver, and expose both the regular and property mailbox protocols as a higher level that uses the low-level mailbox functionality? The concept of the lower 4 bits of mailbox data being a channel ID might belong in the higher protocol level rather than the lower HW layer? -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html