Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753770AbaJ2Ddv (ORCPT ); Tue, 28 Oct 2014 23:33:51 -0400 Received: from mga11.intel.com ([192.55.52.93]:22265 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753466AbaJ2Dds (ORCPT ); Tue, 28 Oct 2014 23:33:48 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.04,807,1406617200"; d="scan'208";a="613180765" From: Lv Zheng To: "Rafael J. Wysocki" , Len Brown Cc: Lv Zheng , Lv Zheng , , linux-acpi@vger.kernel.org Subject: [PATCH v2 1/2] Revert "ACPI / EC: Add support to disallow QR_EC to be issued before completing previous QR_EC" Date: Wed, 29 Oct 2014 11:33:43 +0800 Message-Id: <79ca204b4d6632c596b6ff33133e99c471b3d633.1414553399.git.lv.zheng@intel.com> X-Mailer: git-send-email 1.7.10 In-Reply-To: References: <544CE637.7000406@odi.ch> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org It is reported that the following commit breaks Samsung hardware: Commit: 558e4736f2e1b0e6323adf7a5e4df77ed6cfc1a4. Subject: ACPI / EC: Add support to disallow QR_EC to be issued before completing previous QR_EC Which means the Samsung behavior conflicts with the Acer behavior. 1. Samsung may behave like: [ +event 1 ] SCI_EVT set [ +event 2 ] SCI_EVT set write QR_EC read event [ -event 1 ] SCI_EVT clear Without the above commit, Samsung can work: [ +event 1 ] SCI_EVT set [ +event 2 ] SCI_EVT set write QR_EC CAN prepare next QR_EC as SCI_EVT=1 read event [ -event 1 ] SCI_EVT clear write QR_EC read event [ -event 2 ] SCI_EVT clear With the above commit, Samsung cannot work: [ +event 1 ] SCI_EVT set [ +event 2 ] SCI_EVT set write QR_EC read event [ -event 1 ] SCI_EVT clear CANNOT prepare next QR_EC as SCI_EVT=0 2. Acer may behave like: [ +event 1 ] SCI_EVT set [ +event 2 ] write QR_EC read event [ -event 1 ] SCI_EVT clear [ +event 2 ] SCI_EVT set Without the above commit, Acer cannot work when there is only 1 event: [ +event 1 ] SCI_EVT set write QR_EC can prepared next QR_EC as SCI_EVT=1 read event [ -event 1 ] SCI_EVT clear CANNOT write QR_EC as SCI_EVT=0 With the above commit, Acer can work: [ +event 1 ] SCI_EVT set [ +event 2 ] write QR_EC read event [ -event 1 ] SCI_EVT set can prepare next QR_EC because SCI_EVT=0 CAN write QR_EC as SCI_EVT=1 Since Acer can also work with only the following commit applied: Commit: 3afcf2ece453e1a8c2c6de19cdf06da3772a1b08 Subject: ACPI / EC: Add support to disallow QR_EC to be issued when SCI_EVT isn't set We can revert the above commit. This reverts commit 558e4736f2e1b0e6323adf7a5e4df77ed6cfc1a4. Conflicts: drivers/acpi/ec.c Reference: https://bugzilla.kernel.org/show_bug.cgi?id=44161 Reported-and-tested-by: Ortwin Gl¨¹ck Signed-off-by: Lv Zheng --- drivers/acpi/ec.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index 3d304ff..31b699f 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -334,13 +334,13 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, pr_debug("***** Command(%s) started *****\n", acpi_ec_cmd_string(t->command)); start_transaction(ec); - spin_unlock_irqrestore(&ec->lock, tmp); - ret = ec_poll(ec); - spin_lock_irqsave(&ec->lock, tmp); if (ec->curr->command == ACPI_EC_COMMAND_QUERY) { clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); pr_debug("***** Event stopped *****\n"); } + spin_unlock_irqrestore(&ec->lock, tmp); + ret = ec_poll(ec); + spin_lock_irqsave(&ec->lock, tmp); pr_debug("***** Command(%s) stopped *****\n", acpi_ec_cmd_string(t->command)); ec->curr = NULL; -- 1.7.10 -- 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/