From patchwork Mon Sep 7 11:03:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mika Westerberg X-Patchwork-Id: 11761885 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2DC3259D for ; Mon, 7 Sep 2020 17:53:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1F9B3208C7 for ; Mon, 7 Sep 2020 17:53:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730810AbgIGRxK (ORCPT ); Mon, 7 Sep 2020 13:53:10 -0400 Received: from mga18.intel.com ([134.134.136.126]:29151 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728897AbgIGLWx (ORCPT ); Mon, 7 Sep 2020 07:22:53 -0400 IronPort-SDR: KJg6LNaFUQva6a0+CmI4Bt1E+C7+SI5HQguGHn9kU8Z6xt15795w584FHWLtGR9Ujj4cxluusJ c0X9NWiB4GWQ== X-IronPort-AV: E=McAfee;i="6000,8403,9736"; a="145696982" X-IronPort-AV: E=Sophos;i="5.76,401,1592895600"; d="scan'208";a="145696982" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Sep 2020 04:03:43 -0700 IronPort-SDR: 9IXG5z2Zamb8VXZqHIJLIe3ucrY1MV9J/z5bHNOeK7xSRJO6ZDr9TaT6V6rEjIUDUeVSgnLpEN BlBkVo83f1qw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.76,401,1592895600"; d="scan'208";a="343193312" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga007.jf.intel.com with ESMTP; 07 Sep 2020 04:03:41 -0700 Received: by black.fi.intel.com (Postfix, from userid 1001) id 8141715D; Mon, 7 Sep 2020 14:03:40 +0300 (EEST) From: Mika Westerberg To: linux-usb@vger.kernel.org Cc: Michael Jamet , Yehezkel Bernat , Andreas Noever , Lukas Wunner , Kai-Heng Feng , Mika Westerberg Subject: [PATCH] thunderbolt: Retry DROM read once if parsing fails Date: Mon, 7 Sep 2020 14:03:40 +0300 Message-Id: <20200907110340.71031-1-mika.westerberg@linux.intel.com> X-Mailer: git-send-email 2.28.0 MIME-Version: 1.0 Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Kai-Heng reported that sometimes DROM parsing of ASUS PA27AC Thunderbolt 3 monitor fails. This makes the driver to fail to add the device so only DisplayPort tunneling is functional. It is not clear what exactly happens but waiting for 100 ms and retrying the read seems to work this around so we do that here. Link: https://bugzilla.kernel.org/show_bug.cgi?id=206493 Reported-by: Kai-Heng Feng Tested-by: Kai-Heng Feng Cc: stable@vger.kernel.org Signed-off-by: Mika Westerberg --- drivers/thunderbolt/eeprom.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/drivers/thunderbolt/eeprom.c b/drivers/thunderbolt/eeprom.c index 3ebca44ab3fa..0c8471be3e32 100644 --- a/drivers/thunderbolt/eeprom.c +++ b/drivers/thunderbolt/eeprom.c @@ -7,6 +7,7 @@ */ #include +#include #include #include #include "tb.h" @@ -389,8 +390,8 @@ static int tb_drom_parse_entries(struct tb_switch *sw) struct tb_drom_entry_header *entry = (void *) (sw->drom + pos); if (pos + 1 == drom_size || pos + entry->len > drom_size || !entry->len) { - tb_sw_warn(sw, "drom buffer overrun, aborting\n"); - return -EIO; + tb_sw_warn(sw, "DROM buffer overrun\n"); + return -EILSEQ; } switch (entry->type) { @@ -526,7 +527,8 @@ int tb_drom_read(struct tb_switch *sw) u16 size; u32 crc; struct tb_drom_header *header; - int res; + int res, retries = 1; + if (sw->drom) return 0; @@ -612,7 +614,17 @@ int tb_drom_read(struct tb_switch *sw) tb_sw_warn(sw, "drom device_rom_revision %#x unknown\n", header->device_rom_revision); - return tb_drom_parse_entries(sw); + res = tb_drom_parse_entries(sw); + /* If the DROM parsing fails, wait a moment and retry once */ + if (res == -EILSEQ && retries--) { + tb_sw_warn(sw, "parsing DROM failed, retrying\n"); + msleep(100); + res = tb_drom_read_n(sw, 0, sw->drom, size); + if (!res) + goto parse; + } + + return res; err: kfree(sw->drom); sw->drom = NULL;