From nobody Sat Jan 3 04:14:46 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 72958E9272B for ; Thu, 5 Oct 2023 19:25:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231625AbjJETZI (ORCPT ); Thu, 5 Oct 2023 15:25:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33880 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231272AbjJETY4 (ORCPT ); Thu, 5 Oct 2023 15:24:56 -0400 Received: from hosting.gsystem.sk (hosting.gsystem.sk [212.5.213.30]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 2CD68DE; Thu, 5 Oct 2023 12:24:50 -0700 (PDT) Received: from gsql.ggedos.sk (off-20.infotel.telecom.sk [212.5.213.20]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by hosting.gsystem.sk (Postfix) with ESMTPSA id 2D0C87A072E; Thu, 5 Oct 2023 21:24:48 +0200 (CEST) From: Ondrej Zary To: Damien Le Moal , Sudip Mukherjee Cc: Christoph Hellwig , Sergey Shtylyov , Tim Waugh , linux-parport@lists.infradead.org, linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 4/4] ata: pata_parport: fit3: implement IDE command set registers Date: Thu, 5 Oct 2023 21:24:40 +0200 Message-Id: <20231005192440.4047-5-linux@zary.sk> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20231005192440.4047-1-linux@zary.sk> References: <20231005192440.4047-1-linux@zary.sk> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" fit3 protocol driver does not support accessing IDE control registers (device control/altstatus). The DOS driver does not use these registers either (as observed from DOSEMU trace). But the HW seems to be capable of accessing these registers - I simply tried bit 3 and it works! The control register is required to properly reset ATAPI devices or they will be detected only once (after a power cycle). Tested with EXP Computer CD-865 with MC-1285B EPP cable and TransDisk 3000. Signed-off-by: Ondrej Zary Reviewed-by: Sergey Shtylyov --- drivers/ata/pata_parport/fit3.c | 14 ++------------ 1 file changed, 2 insertions(+), 12 deletions(-) diff --git a/drivers/ata/pata_parport/fit3.c b/drivers/ata/pata_parport/fit= 3.c index bad7aa920cdc..d2b81cf2e16d 100644 --- a/drivers/ata/pata_parport/fit3.c +++ b/drivers/ata/pata_parport/fit3.c @@ -9,11 +9,6 @@ * * The TD-2000 and certain older devices use a different protocol. * Try the fit2 protocol module with them. - * - * NB: The FIT adapters do not appear to support the control - * registers. So, we map ALT_STATUS to STATUS and NO-OP writes - * to the device control register - this means that IDE reset - * will not work on these devices. */ =20 #include @@ -37,8 +32,7 @@ =20 static void fit3_write_regr(struct pi_adapter *pi, int cont, int regr, int= val) { - if (cont =3D=3D 1) - return; + regr +=3D cont << 3; =20 switch (pi->mode) { case 0: @@ -59,11 +53,7 @@ static int fit3_read_regr(struct pi_adapter *pi, int con= t, int regr) { int a, b; =20 - if (cont) { - if (regr !=3D 6) - return 0xff; - regr =3D 7; - } + regr +=3D cont << 3; =20 switch (pi->mode) { case 0: --=20 Ondrej Zary