Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756812AbYC1Mvo (ORCPT ); Fri, 28 Mar 2008 08:51:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756409AbYC1Mu6 (ORCPT ); Fri, 28 Mar 2008 08:50:58 -0400 Received: from SpacedOut.fries.net ([67.64.210.234]:56316 "EHLO SpacedOut.fries.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756369AbYC1Mu5 (ORCPT ); Fri, 28 Mar 2008 08:50:57 -0400 Date: Fri, 28 Mar 2008 07:27:20 -0500 From: David Fries To: linux-kernel@vger.kernel.org Cc: Evgeniy Polyakov Subject: [PATCH 26/35] W1: ds2490.c ds_write_bit disable readback Message-ID: <20080328122720.GA3613@spacedout.fries.net> References: <200803272343.m2RNhDac017650@SpacedOut.fries.net> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="LG5jgFgJbJFFiAfj" Content-Disposition: inline In-Reply-To: <200803272343.m2RNhDac017650@SpacedOut.fries.net> User-Agent: Mutt/1.5.4i X-Greylist: Sender is SPF-compliant, not delayed by milter-greylist-3.0 (SpacedOut.fries.net [127.0.0.1]); Fri, 28 Mar 2008 07:27:20 -0500 (CDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1739 Lines: 57 --LG5jgFgJbJFFiAfj Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable ds2490.c 1.11 ds_write_bit doesn't read the input buffer, so add COMM_ICP and a comment that it will no longer generate a read back data byte. If there is an extra data byte later on then it will cause an error and discard what data was there. Signed-off-by: David Fries --- drivers/w1/masters/ds2490.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-) diff --git a/drivers/w1/masters/ds2490.c b/drivers/w1/masters/ds2490.c index 6778bd3..e0e9325 100644 --- a/drivers/w1/masters/ds2490.c +++ b/drivers/w1/masters/ds2490.c @@ -525,7 +525,12 @@ static int ds_write_bit(struct ds_device *dev, u8 bit) int err; struct ds_status st; =20 - err =3D ds_send_control(dev, COMM_BIT_IO | COMM_IM | (bit ? COMM_D : 0), = 0); + /* Set COMM_ICP to write without a readback. Note, this will + * produce one time slot, a down followed by an up with COMM_D + * only determing the timing. + */ + err =3D ds_send_control(dev, COMM_BIT_IO | COMM_IM | COMM_ICP | + (bit ? COMM_D : 0), 0); if (err) return err; =20 --=20 1.4.4.4 --LG5jgFgJbJFFiAfj Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.1 (GNU/Linux) iD8DBQFH7OQoAI852cse6PARAo3SAJ9XKJhmehuuhSiYperq/wA0Vw+b0QCfdI+V c6V3oiJUR9CRYuMmeCdv600= =szUm -----END PGP SIGNATURE----- --LG5jgFgJbJFFiAfj-- -- 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/