From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932502AbcGOKb3 (ORCPT ); Fri, 15 Jul 2016 06:31:29 -0400 Received: from mga14.intel.com ([192.55.52.115]:48551 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932187AbcGOKb2 (ORCPT ); Fri, 15 Jul 2016 06:31:28 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.28,367,1464678000"; d="asc'?scan'208";a="995820377" From: Felipe Balbi To: Oliver Neukum Cc: Bin Gao , Heikki Krogerus , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, Bin Gao , Chandra Sekhar Anagani Subject: Re: [PATCH 1/2] usb: typec: Add USB Power Delivery sink port support In-Reply-To: <1468572250.2195.11.camel@suse.com> References: <20160715021405.GB128987@worksta> <87zipjgy6n.fsf@linux.intel.com> <1468572250.2195.11.camel@suse.com> User-Agent: Notmuch/0.22+58~g3a45d29 (https://notmuchmail.org) Emacs/25.0.95.2 (x86_64-pc-linux-gnu) Date: Fri, 15 Jul 2016 13:30:25 +0300 Message-ID: <87poqfgpmm.fsf@linux.intel.com> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha256; protocol="application/pgp-signature" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-=-= Content-Type: text/plain Content-Transfer-Encoding: quoted-printable Hi, Oliver Neukum writes: > On Fri, 2016-07-15 at 10:25 +0300, Felipe Balbi wrote: >> > +int pd_sink_queue_msg(struct pd_sink_msg *msg) >> > +{ >> > + unsigned long flags; >> > + struct pd_sink_port *port; >> > + >> > + if (msg->port < 0 || msg->port >=3D MAX_NR_SINK_PORTS) { >> > + pr_err("Invalid port number\n"); >> > + return -EINVAL; >> > + } >> > + >> > + port =3D sink_ports[msg->port]; >> > + >> > + spin_lock_irqsave(&port->rx_lock, flags); >> > + list_add_tail(&msg->list, &port->rx_list); >> > + spin_unlock_irqrestore(&port->rx_lock, flags); >> > + >> > + queue_work(port->rx_wq, &port->rx_work); >>=20 >> can we really queue several messages at a time? It seems unfeasible to >> me. It's not like we can queue several power request in a role. Why do >> you need this workqueue? Why don't you process message here, in place? > > A reset can come at any time. right, but that's not how this is being used. IMHO, rx_work is a misnomer. If you look at how typec_wcove (patch 2 in this series) uses it, you'll see that pd_sink_queue_msg() is called to queue a reply to a message that was *already* received. We can't have two replies, right? In any case, this is a minor problem. =2D-=20 balbi --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBCAAGBQJXiLtBAAoJEIaOsuA1yqREizoQALGONXM31A8iWlGJKNs8h/+y UOWlys9+dmCOAKmV41URA8bs+AKn8AdFo8mQY/3WnDEUrIs9nELUOssw77NaooNM wHyj+YdORwcR2DgA0qlvSOXQi0mehaBxFZovZMLdkjvx2aILsh5tytnrLkWN3x5e nkQEEiDKvVBO5DOWLb2+4t5trFe2XmGAwRA13qoCe0b3qH6TZqWhCyInDPnEreSe CaJ4nngC+qE5MlV4StuDtXj9eQdDX3GgOz1KMULqy+oEQvz/7moMVlQqrgymBRAV 2mdvTfWxSY/wlvFxfJHaPha1fMwAE5xrvwDDq8Ywl6InY8g/AqJyTsGzVzXnC5xO jGrX/RZakrGYwnAhWZii3Mbrv7iAKOI2joioMtbDILuYPeFkhGlbrCFDCqqwYQIW hToBrMS8EYPh/px3TczD8p/iYmWjlGw9Gss9IFIgh3VPlZaUhWv5tu3IM1NS7cUk 2FjMq4SMPAYfaggziPfmlghQCb8eG9XqCKNBigKPpgOZMPy+KvgYKdOwN/u7w6fh 1/7urEX5AkEVufqUEylchOPULJI2s5BRmHH18Ajomqe0xhafloeSNm62q2nmOO85 5EsKH4wkt1ByPyifmzQPvqtdmsEt++6O0SauhUddtrMtnZzuqA9Kszpq+dO1ai1n O869RCIdv3jULhsQee/O =Ku0O -----END PGP SIGNATURE----- --=-=-=--