From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758773AbYKQHgd (ORCPT ); Mon, 17 Nov 2008 02:36:33 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756062AbYKQHVq (ORCPT ); Mon, 17 Nov 2008 02:21:46 -0500 Received: from kroah.org ([198.145.64.141]:38764 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756008AbYKQHVn (ORCPT ); Mon, 17 Nov 2008 02:21:43 -0500 Date: Sun, 16 Nov 2008 23:17:10 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , Willy Tarreau , Rodrigo Rubira Branco , Jake Edge , Eugene Teo , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Alexey Starikovskiy , Len Brown , "Rafael J. Wysocki" , Greg Kroah-Hartman Subject: [patch 43/46] ACPI: EC: wait for last write gpe Message-ID: <20081117071709.GR29522@kroah.com> References: <20081117070621.430169021@blue.kroah.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename="acpi-ec-wait-for-last-write-gpe.patch" In-Reply-To: <20081117071333.GA29522@kroah.com> User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.27-stable review patch. If anyone has any objections, please let us know. ------------------ From: Alexey Starikovskiy commit dd15f8c42af09031e27da5b4d697ce925511f2e1 upstream. There is a possibility that EC might break if next command is issued within 1 us after write or burst-disable command. Suggestd-by: Zhao Yakui Signed-off-by: Alexey Starikovskiy Signed-off-by: Len Brown Cc: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/acpi/ec.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -102,6 +102,7 @@ struct transaction { u8 command; u8 wlen; u8 rlen; + bool done; }; static struct acpi_ec { @@ -178,7 +179,7 @@ static int ec_transaction_done(struct ac unsigned long flags; int ret = 0; spin_lock_irqsave(&ec->curr_lock, flags); - if (!ec->curr || (!ec->curr->wlen && !ec->curr->rlen)) + if (!ec->curr || ec->curr->done) ret = 1; spin_unlock_irqrestore(&ec->curr_lock, flags); return ret; @@ -195,17 +196,20 @@ static void gpe_transaction(struct acpi_ acpi_ec_write_data(ec, *(ec->curr->wdata++)); --ec->curr->wlen; } else - /* false interrupt, state didn't change */ - ++ec->curr->irq_count; - + goto err; } else if (ec->curr->rlen > 0) { if ((status & ACPI_EC_FLAG_OBF) == 1) { *(ec->curr->rdata++) = acpi_ec_read_data(ec); - --ec->curr->rlen; + if (--ec->curr->rlen == 0) + ec->curr->done = true; } else - /* false interrupt, state didn't change */ - ++ec->curr->irq_count; - } + goto err; + } else if (ec->curr->wlen == 0 && (status & ACPI_EC_FLAG_IBF) == 0) + ec->curr->done = true; + goto unlock; +err: + /* false interrupt, state didn't change */ + ++ec->curr->irq_count; unlock: spin_unlock_irqrestore(&ec->curr_lock, flags); } @@ -265,6 +269,7 @@ static int acpi_ec_transaction_unlocked( spin_lock_irqsave(&ec->curr_lock, tmp); /* following two actions should be kept atomic */ t->irq_count = 0; + t->done = false; ec->curr = t; acpi_ec_write_cmd(ec, ec->curr->command); if (ec->curr->command == ACPI_EC_COMMAND_QUERY) --