Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753352AbbDGLNf (ORCPT ); Tue, 7 Apr 2015 07:13:35 -0400 Received: from v094114.home.net.pl ([79.96.170.134]:62344 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752479AbbDGLNd (ORCPT ); Tue, 7 Apr 2015 07:13:33 -0400 From: "Rafael J. Wysocki" To: Mika Westerberg Cc: Feng Kan , patches , Jassi Brar , "linux-kernel@vger.kernel.org" , "linux-acpi@vger.kernel.org" Subject: Re: [PATCH] mailbox: add ACPI support for mailbox framework Date: Tue, 07 Apr 2015 13:37:56 +0200 Message-ID: <11619620.g1RKbURH6u@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/3.19.0+; KDE/4.11.5; x86_64; ; ) In-Reply-To: <20150407084143.GP17830@lahna.fi.intel.com> References: <1427836680-13008-1-git-send-email-fkan@apm.com> <20150407084143.GP17830@lahna.fi.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3417 Lines: 80 On Tuesday, April 07, 2015 11:41:43 AM Mika Westerberg wrote: > On Thu, Apr 02, 2015 at 11:04:24AM -0700, Feng Kan wrote: > > On Thu, Apr 2, 2015 at 2:07 AM, Mika Westerberg > > wrote: > > > On Wed, Apr 01, 2015 at 10:01:45AM -0700, Feng Kan wrote: > > >> On Wed, Apr 1, 2015 at 12:45 AM, Mika Westerberg > > >> wrote: > > >> > On Tue, Mar 31, 2015 at 02:18:00PM -0700, Feng Kan wrote: > > >> >> This will add support for ACPI parsing of the mboxes attribute > > >> >> when booting with ACPI table. The client will have a attribute > > >> >> mimic the dts call "mboxes". In the ACPI case, the client will > > >> >> mark "mboxes" with the ACPI HID of the mbox it wishes to use. > > >> >> > > >> >> Name (_DSD, Package () { > > >> >> ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), > > >> >> Package () { > > >> >> Package (2) {"mboxes", "ACPIHID"}, > > >> >> } > > >> >> }) > > >> > > > >> > Instead of this, why not match against the DT compatible property? > > >> > > > >> > Name (_HID, "PRP0001") > > >> > > > >> > Name (_DSD, Package () { > > >> > ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), > > >> > Package () { > > >> > Package (2) {"compatible", "your-dt-compatible-string"}, > > >> > } > > >> > }) > > >> I think my description was not clear enough. The _DSD section is not > > >> meant to identify the mailbox driver, but used by the acpi node that will > > >> request the mailbox channel. The dts version would be as below. > > >> > > >> mailbox: { > > >> } > > >> > > >> user-mbox: { > > >> mboxes: <&mailbox 0> > > >> } > > >> > > >> The mboxes attribute in the user of the mbox has to specify the HID of the > > >> mbox in order to retrieve channel pointer. > > > > > > Okay, then I think you can use reference instead of _HID, like > > > > > > // The mailbox device > > > Device (MLBX) { > > > } > > > > > > // User-mbox device > > > Device (USBX) { > > > Name (_DSD, Package () { > > > ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), > > > Package () { > > > Package () {"mboxes", Package () {^^MLBX, 0}}), > > > } > > > }) > > > } > > > > Thanks, will try this. A side question on your previous reply. Would you > > prefer a new driver using the PRP0001 or an actual proper HID. > > If you have existing DT bindings for this, then PRP0001 is fine. > Otherwise you should use the proper _HID for this particular device. To be precise, PRP0001 specifically means "Use the 'compatible' property to find the driver for this device", so if *that* is what you want to do, you can use PRP0001 as the _HID. For Windows (and such) compatibility, you can provide a _CID whith a (list of) proper device ID(s) in addition to that. -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/