From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7E012C10F14 for ; Thu, 3 Oct 2019 17:41:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 55CEC20862 for ; Thu, 3 Oct 2019 17:41:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570124470; bh=fik+i5HOycM4aEtSccDBSMO6kukqh4PeAR2iNgi49dk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=zRkzjVpJzJCXnxX4ueVXs2YihCKs5dhGKjUrny/jYHteMWV7yxOPfidRzTZkzxQTN 7JXUm/kpNsv5F5F0ksgtVxhlffx9BN/CtxKkimrgMMCE8UoJ0L4KJnDupdF7sV1X7U Ja+dus3k2dZObIIPF3+t299ILMvh/cSSlmUo/bOs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731327AbfJCP7T (ORCPT ); Thu, 3 Oct 2019 11:59:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:42104 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729160AbfJCP7J (ORCPT ); Thu, 3 Oct 2019 11:59:09 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0A06320830; Thu, 3 Oct 2019 15:59:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570118348; bh=fik+i5HOycM4aEtSccDBSMO6kukqh4PeAR2iNgi49dk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HdopCgV3LXuEa2LN3iYWJWlLHNQCdpn2sInW3zEVoW9/XWBWo1WP7tW3w2UexfHEe eDnDxzr41l7K/WFAXC60Kg0YU3Y/JMph046xU1l8PLJzDuX1quqDhOwnYUvtdEHgpV eWxDtWk/um4zb+36oq07IXNfXn9A9N4kSjgTMvjM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Takashi Sakamoto , Takashi Iwai Subject: [PATCH 4.4 77/99] ALSA: firewire-tascam: check intermediate state of clock status and retry Date: Thu, 3 Oct 2019 17:53:40 +0200 Message-Id: <20191003154334.566717289@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191003154252.297991283@linuxfoundation.org> References: <20191003154252.297991283@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Takashi Sakamoto commit e1a00b5b253a4f97216b9a33199a863987075162 upstream. 2 bytes in MSB of register for clock status is zero during intermediate state after changing status of sampling clock in models of TASCAM FireWire series. The duration of this state differs depending on cases. During the state, it's better to retry reading the register for current status of the clock. In current implementation, the intermediate state is checked only when getting current sampling transmission frequency, then retry reading. This care is required for the other operations to read the register. This commit moves the codes of check and retry into helper function commonly used for operations to read the register. Fixes: e453df44f0d6 ("ALSA: firewire-tascam: add PCM functionality") Cc: # v4.4+ Signed-off-by: Takashi Sakamoto Link: https://lore.kernel.org/r/20190910135152.29800-3-o-takashi@sakamocchi.jp Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/firewire/tascam/tascam-stream.c | 42 ++++++++++++++++++++++------------ 1 file changed, 28 insertions(+), 14 deletions(-) --- a/sound/firewire/tascam/tascam-stream.c +++ b/sound/firewire/tascam/tascam-stream.c @@ -9,20 +9,37 @@ #include #include "tascam.h" +#define CLOCK_STATUS_MASK 0xffff0000 +#define CLOCK_CONFIG_MASK 0x0000ffff + #define CALLBACK_TIMEOUT 500 static int get_clock(struct snd_tscm *tscm, u32 *data) { + int trial = 0; __be32 reg; int err; - err = snd_fw_transaction(tscm->unit, TCODE_READ_QUADLET_REQUEST, - TSCM_ADDR_BASE + TSCM_OFFSET_CLOCK_STATUS, - ®, sizeof(reg), 0); - if (err >= 0) + while (trial++ < 5) { + err = snd_fw_transaction(tscm->unit, TCODE_READ_QUADLET_REQUEST, + TSCM_ADDR_BASE + TSCM_OFFSET_CLOCK_STATUS, + ®, sizeof(reg), 0); + if (err < 0) + return err; + *data = be32_to_cpu(reg); + if (*data & CLOCK_STATUS_MASK) + break; + + // In intermediate state after changing clock status. + msleep(50); + } - return err; + // Still in the intermediate state. + if (trial >= 5) + return -EAGAIN; + + return 0; } static int set_clock(struct snd_tscm *tscm, unsigned int rate, @@ -35,7 +52,7 @@ static int set_clock(struct snd_tscm *ts err = get_clock(tscm, &data); if (err < 0) return err; - data &= 0x0000ffff; + data &= CLOCK_CONFIG_MASK; if (rate > 0) { data &= 0x000000ff; @@ -80,17 +97,14 @@ static int set_clock(struct snd_tscm *ts int snd_tscm_stream_get_rate(struct snd_tscm *tscm, unsigned int *rate) { - u32 data = 0x0; - unsigned int trials = 0; + u32 data; int err; - while (data == 0x0 || trials++ < 5) { - err = get_clock(tscm, &data); - if (err < 0) - return err; + err = get_clock(tscm, &data); + if (err < 0) + return err; - data = (data & 0xff000000) >> 24; - } + data = (data & 0xff000000) >> 24; /* Check base rate. */ if ((data & 0x0f) == 0x01)