From patchwork Wed Mar 5 10:48:06 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Takashi Sakamoto X-Patchwork-Id: 3772881 X-Patchwork-Delegate: tiwai@suse.de Return-Path: X-Original-To: patchwork-alsa-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 374269F1EE for ; Wed, 5 Mar 2014 11:00:46 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 35F4B2021E for ; Wed, 5 Mar 2014 11:00:45 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) by mail.kernel.org (Postfix) with ESMTP id DDFBC20211 for ; Wed, 5 Mar 2014 11:00:43 +0000 (UTC) Received: by alsa0.perex.cz (Postfix, from userid 1000) id 9AB132658A3; Wed, 5 Mar 2014 12:00:41 +0100 (CET) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from alsa0.perex.cz (localhost [IPv6:::1]) by alsa0.perex.cz (Postfix) with ESMTP id 10D9B2659F6; Wed, 5 Mar 2014 11:52:15 +0100 (CET) X-Original-To: alsa-devel@alsa-project.org Delivered-To: alsa-devel@alsa-project.org Received: by alsa0.perex.cz (Postfix, from userid 1000) id 911F52659F3; Wed, 5 Mar 2014 11:52:12 +0100 (CET) Received: from smtp311.phy.lolipop.jp (smtp311.phy.lolipop.jp [210.157.22.79]) by alsa0.perex.cz (Postfix) with ESMTP id E56432658A3 for ; Wed, 5 Mar 2014 11:49:06 +0100 (CET) Received: from smtp311.phy.lolipop.lan (HELO smtp311.phy.lolipop.jp) (172.17.1.11) (smtp-auth username m12129643-o-takashi, mechanism plain) by smtp311.phy.lolipop.jp (qpsmtpd/0.82) with ESMTPA; Wed, 05 Mar 2014 19:49:06 +0900 Received: from 127.0.0.1 (127.0.0.1) by smtp311.phy.lolipop.jp (LOLIPOP-Fsecure); Wed, 05 Mar 2014 19:48:28 +0900 (JST) X-Virus-Status: clean(LOLIPOP-Fsecure) From: Takashi Sakamoto To: clemens@ladisch.de, tiwai@suse.de, perex@perex.cz Date: Wed, 5 Mar 2014 19:48:06 +0900 Message-Id: <1394016507-15761-19-git-send-email-o-takashi@sakamocchi.jp> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1394016507-15761-1-git-send-email-o-takashi@sakamocchi.jp> References: <5316963F.1000206@sakamocchi.jp> <1394016507-15761-1-git-send-email-o-takashi@sakamocchi.jp> Cc: alsa-devel@alsa-project.org, ffado-devel@lists.sf.net Subject: [alsa-devel] [PATCH 18/39] firewire-lib: Add a fallback at RCODE_CANCELLED X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org X-Virus-Scanned: ClamAV using ClamSMTP I confirm that some devices often send no response against driver's request even if the devices handle the request. In this case, drivers should not retry the request because it's not clear whether the devices already handled an operation of the request or not. The second request may bring errors or make no sence if the request was handled. This patch adds a flag, FW_RETURN_TIMEOUT, for snd_fw_transaction(). With this flag, this function returns -ETIMEOUT when fw_run_transaction() returns RCODE_CALCELLED. For FCP, this patch modifies fcp_avc_transaction() with this flag. The -ETIMEDOUT is handled as success. Linux Firewire Subsystem currently gives 2,000msec for default timeout (See DEFAULT_SPLIT_TIMEOUT in core-card.c). firewire-lib gives 125msec for wait_event_timeout(). As a result, in worst case that all of three retries are timeout and devices don't send responses, fcp_avc_transaction() returns 6sec later ((2000 + 125) msec * 3 times). But this is rare. For CMP, this patch modifies pcr_modify() with this flag. The -ETIMEOUT generates another read transaction to check current value of PCR. If this read transaction returns errors, then pcr_modify() returns the error code. --- sound/firewire/cmp.c | 23 +++++++++++++++++++++-- sound/firewire/fcp.c | 5 +++-- sound/firewire/lib.c | 6 +++++- sound/firewire/lib.h | 1 + 4 files changed, 30 insertions(+), 5 deletions(-) diff --git a/sound/firewire/cmp.c b/sound/firewire/cmp.c index a8199fd..73f5f26 100644 --- a/sound/firewire/cmp.c +++ b/sound/firewire/cmp.c @@ -89,13 +89,32 @@ static int pcr_modify(struct cmp_connection *c, err = snd_fw_transaction( c->resources.unit, TCODE_LOCK_COMPARE_SWAP, get_offset(c, false), buffer, 8, - FW_FIXED_GENERATION | c->resources.generation); + FW_FIXED_GENERATION | c->resources.generation | + FW_RETURN_TIMEOUT); if (err < 0) { if (err == -EAGAIN && bus_reset_handling == SUCCEED_ON_BUS_RESET) err = 0; - return err; + + if (err != -ETIMEDOUT) + return err; + + /* Check current PCR. */ + err = snd_fw_transaction( + c->resources.unit, TCODE_READ_QUADLET_REQUEST, + get_offset(c, false), buffer, 4, + FW_FIXED_GENERATION | c->resources.generation); + if (err < 0) + return err; + + /* The lock transaction may be failed, retry */ + if (buffer[0] != buffer[1]) { + buffer[0] = c->last_pcr_value; + continue; + } + + break; } if (buffer[0] == old_arg) /* success? */ diff --git a/sound/firewire/fcp.c b/sound/firewire/fcp.c index e903ddb..6fc813f 100644 --- a/sound/firewire/fcp.c +++ b/sound/firewire/fcp.c @@ -245,8 +245,9 @@ int fcp_avc_transaction(struct fw_unit *unit, : TCODE_WRITE_BLOCK_REQUEST; ret = snd_fw_transaction(t.unit, tcode, CSR_REGISTER_BASE + CSR_FCP_COMMAND, - (void *)command, command_size, 0); - if (ret < 0) + (void *)command, command_size, + FW_RETURN_TIMEOUT); + if ((ret < 0) && (ret != -ETIMEDOUT)) break; wait_event_timeout(t.wait, t.state != STATE_PENDING, diff --git a/sound/firewire/lib.c b/sound/firewire/lib.c index 7409edb..de42748 100644 --- a/sound/firewire/lib.c +++ b/sound/firewire/lib.c @@ -22,7 +22,7 @@ * @length: length of @buffer * @flags: use %FW_FIXED_GENERATION and add the generation value to attempt the * request only in that generation; use %FW_QUIET to suppress error - * messages + * messages; use %FW_RETURN_TIMEOUT to avoid retry at RCODE_CANCELLED * * Submits an asynchronous request to the target device, and waits for the * response. The node ID and the current generation are derived from @unit. @@ -53,6 +53,10 @@ int snd_fw_transaction(struct fw_unit *unit, int tcode, if (rcode == RCODE_GENERATION && (flags & FW_FIXED_GENERATION)) return -EAGAIN; + /* timeout */ + if ((rcode == RCODE_CANCELLED) && (flags & FW_RETURN_TIMEOUT)) + return -ETIMEDOUT; + if (rcode_is_permanent_error(rcode) || ++tries >= 3) { if (!(flags & FW_QUIET)) dev_err(&unit->device, diff --git a/sound/firewire/lib.h b/sound/firewire/lib.h index 02cfabc..b8ea90b 100644 --- a/sound/firewire/lib.h +++ b/sound/firewire/lib.h @@ -9,6 +9,7 @@ struct fw_unit; #define FW_GENERATION_MASK 0x00ff #define FW_FIXED_GENERATION 0x0100 #define FW_QUIET 0x0200 +#define FW_RETURN_TIMEOUT 0x0400 int snd_fw_transaction(struct fw_unit *unit, int tcode, u64 offset, void *buffer, size_t length,