applied to acpi-test. we struggled with ec burst mode for a long time before enabling it finally in 2005. have we had any problems with it since then that might be addressed by this race? thanks, -Len On Sun, 9 Nov 2008, Alexey Starikovskiy wrote: > 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 > -- 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
