From: Lv Zheng Date: Thu, 21 Aug 2014 06:41:26 +0000 (+0800) Subject: ACPI / EC: Add support to disallow QR_EC to be issued before completing previous... X-Git-Tag: v4.14-rc1~6929^2~1^3 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=558e4736f2e1b0e6323adf7a5e4df77ed6cfc1a4;p=platform%2Fkernel%2Flinux-rpi.git ACPI / EC: Add support to disallow QR_EC to be issued before completing previous QR_EC There is platform refusing to respond QR_EC when SCI_EVT isn't set which is Acer Aspire V5-573G. By disallowing QR_EC to be issued before the previous one has been completed we are able to reduce the possibilities to trigger issues on such platforms. Note that this fix can only reduce the occurrence rate of this issue, but this issue may still occur when such a platform doesn't clear SCI_EVT before or immediately after completing the previous QR_EC transaction. This patch cannot fix the CLEAR_ON_RESUME quirk which also relies on the assumption that the platforms are able to respond even when SCI_EVT isn't set. But this patch is still useful as it can help to reduce the number of scheduled QR_EC work items. Link: https://bugzilla.kernel.org/show_bug.cgi?id=82611 Reported-and-tested-by: Alexander Mezin Signed-off-by: Lv Zheng Cc: 3.16+ # 3.16+ Signed-off-by: Rafael J. Wysocki --- diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index 5e1ed31..9922cc4 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -303,11 +303,11 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, /* following two actions should be kept atomic */ ec->curr = t; start_transaction(ec); - if (ec->curr->command == ACPI_EC_COMMAND_QUERY) - clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); 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); ec->curr = NULL; spin_unlock_irqrestore(&ec->lock, tmp); return ret;