From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexey Starikovskiy Subject: [PATCH] ACPI: EC: Workaround for optimized controllers Date: Thu, 15 Nov 2007 23:14:29 +0300 Message-ID: <20071115201429.12417.39628.stgit@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: Received: from charybdis-ext.suse.de ([195.135.221.2]:55855 "EHLO emea5-mh.id5.novell.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753139AbXKOUOz (ORCPT ); Thu, 15 Nov 2007 15:14:55 -0500 Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: LenBrown Cc: Linux-acpi@vger.kernel.org Some controllers fail to send confirmation GPE after address write. Detect this and don't expect such confirmation in future. This is a generalization of previous workaround (66c5f4e7367b0085652931b2f3366de29e7ff5ec), which did only read address. Reference: http://bugzilla.kernel.org/show_bug.cgi?id=9327 Signed-off-by: Alexey Starikovskiy --- drivers/acpi/ec.c | 35 ++++++++++++++++++++++------------- 1 files changed, 22 insertions(+), 13 deletions(-) diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index 56afe13..d6ddb54 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -75,7 +75,8 @@ enum { EC_FLAGS_WAIT_GPE = 0, /* Don't check status until GPE arrives */ EC_FLAGS_QUERY_PENDING, /* Query is pending */ EC_FLAGS_GPE_MODE, /* Expect GPE to be sent for status change */ - EC_FLAGS_ONLY_IBF_GPE, /* Expect GPE only for IBF = 0 event */ + EC_FLAGS_NO_ADDRESS_GPE, /* Expect GPE only for non-address event */ + EC_FLAGS_ADDRESS, /* Address is being written */ }; static int acpi_ec_remove(struct acpi_device *device, int type); @@ -166,38 +167,45 @@ static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event) static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event, int force_poll) { + int ret = 0; + if (unlikely(test_bit(EC_FLAGS_ADDRESS, &ec->flags) && + test_bit(EC_FLAGS_NO_ADDRESS_GPE, &ec->flags))) + force_poll = 1; if (likely(test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) && likely(!force_poll)) { if (wait_event_timeout(ec->wait, acpi_ec_check_status(ec, event), msecs_to_jiffies(ACPI_EC_DELAY))) - return 0; + goto end; clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags); if (acpi_ec_check_status(ec, event)) { - if (event == ACPI_EC_EVENT_OBF_1) { - /* miss OBF = 1 GPE, don't expect it anymore */ - printk(KERN_INFO PREFIX "missing OBF_1 confirmation," - "switching to degraded mode.\n"); - set_bit(EC_FLAGS_ONLY_IBF_GPE, &ec->flags); + if (test_bit(EC_FLAGS_ADDRESS, &ec->flags)) { + /* miss address GPE, don't expect it anymore */ + printk(KERN_INFO PREFIX "missing address confirmation," + "don't expect it any longer.\n"); + set_bit(EC_FLAGS_NO_ADDRESS_GPE, &ec->flags); } else { /* missing GPEs, switch back to poll mode */ - printk(KERN_INFO PREFIX "missing IBF_1 confirmations," + printk(KERN_INFO PREFIX "missing confirmations," "switch off interrupt mode.\n"); clear_bit(EC_FLAGS_GPE_MODE, &ec->flags); } - return 0; + goto end; } } else { unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY); clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags); while (time_before(jiffies, delay)) { if (acpi_ec_check_status(ec, event)) - return 0; + goto end; } } printk(KERN_ERR PREFIX "acpi_ec_wait timeout," " status = %d, expect_event = %d\n", acpi_ec_read_status(ec), event); - return -ETIME; + ret = -ETIME; + end: + clear_bit(EC_FLAGS_ADDRESS, &ec->flags); + return ret; } static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command, @@ -216,6 +224,9 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command, "write_cmd timeout, command = %d\n", command); goto end; } + /* mark the address byte written to EC */ + if (rdata_len + wdata_len > 1) + set_bit(EC_FLAGS_ADDRESS, &ec->flags); set_bit(EC_FLAGS_WAIT_GPE, &ec->flags); acpi_ec_write_data(ec, *(wdata++)); } @@ -231,8 +242,6 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command, clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); for (; rdata_len > 0; --rdata_len) { - if (test_bit(EC_FLAGS_ONLY_IBF_GPE, &ec->flags)) - force_poll = 1; result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, force_poll); if (result) { printk(KERN_ERR PREFIX "read timeout, command = %d\n",