From dd15f8c42af09031e27da5b4d697ce925511f2e1 Mon Sep 17 00:00:00 2001 From: Alexey Starikovskiy Date: Sat, 8 Nov 2008 21:42:30 +0300 Subject: ACPI: EC: wait for last write gpe 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 --- drivers/acpi/ec.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index b340e08cf1d9..cebd65d2e2a9 100644 --- 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 acpi_ec *ec) 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_ec *ec, u8 status) 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(struct acpi_ec *ec, 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) -- cgit v1.2.3