From 79149001105f18bd2285ada109f9229ea24a7571 Mon Sep 17 00:00:00 2001 From: Lv Zheng Date: Wed, 29 Oct 2014 11:33:49 +0800 Subject: ACPI / EC: Fix regression due to conflicting firmware behavior between Samsung and Acer. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit It is reported that Samsung laptops that need to poll events are broken by the following commit: Commit 3afcf2ece453e1a8c2c6de19cdf06da3772a1b08 Subject: ACPI / EC: Add support to disallow QR_EC to be issued when SCI_EVT isn't set The behaviors of the 2 vendor firmwares are conflict: 1. Acer: OSPM shouldn't issue QR_EC unless SCI_EVT is set, firmware automatically sets SCI_EVT as long as there is event queued up. 2. Samsung: OSPM should issue QR_EC whatever SCI_EVT is set, firmware returns 0 when there is no event queued up. This patch is a quick fix to distinguish the behaviors to make Acer behavior only effective for Acer EC firmware so that the breakages on Samsung EC firmware can be avoided. Fixes: 3afcf2ece453 (ACPI / EC: Add support to disallow QR_EC to be issued ...) Link: https://bugzilla.kernel.org/show_bug.cgi?id=44161 Reported-and-tested-by: Ortwin Glück Signed-off-by: Lv Zheng Cc: 3.17+ # 3.17+ [ rjw : Subject ] Signed-off-by: Rafael J. Wysocki --- drivers/acpi/ec.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index 31b699f2d088..5f9b74b9b71f 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -126,6 +126,7 @@ static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */ static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */ static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */ static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */ +static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */ /* -------------------------------------------------------------------------- * Transaction Management @@ -236,13 +237,8 @@ static bool advance_transaction(struct acpi_ec *ec) } return wakeup; } else { - /* - * There is firmware refusing to respond QR_EC when SCI_EVT - * is not set, for which case, we complete the QR_EC - * without issuing it to the firmware. - * https://bugzilla.kernel.org/show_bug.cgi?id=86211 - */ - if (!(status & ACPI_EC_FLAG_SCI) && + if (EC_FLAGS_QUERY_HANDSHAKE && + !(status & ACPI_EC_FLAG_SCI) && (t->command == ACPI_EC_COMMAND_QUERY)) { t->flags |= ACPI_EC_COMMAND_POLL; t->rdata[t->ri++] = 0x00; @@ -1011,6 +1007,18 @@ static int ec_enlarge_storm_threshold(const struct dmi_system_id *id) return 0; } +/* + * Acer EC firmware refuses to respond QR_EC when SCI_EVT is not set, for + * which case, we complete the QR_EC without issuing it to the firmware. + * https://bugzilla.kernel.org/show_bug.cgi?id=86211 + */ +static int ec_flag_query_handshake(const struct dmi_system_id *id) +{ + pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n"); + EC_FLAGS_QUERY_HANDSHAKE = 1; + return 0; +} + /* * On some hardware it is necessary to clear events accumulated by the EC during * sleep. These ECs stop reporting GPEs until they are manually polled, if too @@ -1085,6 +1093,9 @@ static struct dmi_system_id ec_dmi_table[] __initdata = { { ec_clear_on_resume, "Samsung hardware", { DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL}, + { + ec_flag_query_handshake, "Acer hardware", { + DMI_MATCH(DMI_SYS_VENDOR, "Acer"), }, NULL}, {}, }; -- cgit v1.2.3