There is a possibility that EC might break if next command is issued within 1 us after write or burst-disable command. This "possibility" was in EC driver for 3.5 years, after 451566f45a2e6cd10ba56e7220a9dd84ba3ef550. References: http://marc.info/?l=linux-acpi&m=122616284402886&w=4 Cc: Zhao Yakui <yakui.zhao@xxxxxxxxx> Signed-off-by: Alexey Starikovskiy <astarikovskiy@xxxxxxx> --- drivers/acpi/ec.c | 21 +++++++++++++-------- 1 files changed, 13 insertions(+), 8 deletions(-) diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index e5dbe21..d6007ac 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) -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
