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ACPI / EC: Remove old CLEAR_ON_RESUME quirk 

IRQ polling logic has been implemented to drain the post-boot/resume
EC events:

 1. Triggered by the following code, invoked from acpi_ec_enable_event():

	if (!test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
		advance_transaction(ec);

 2. Drained by the following code, invoked after acpi_ec_complete_query():

	if (status & ACPI_EC_FLAG_SCI)
		acpi_ec_submit_query(ec);

This facility is safer than the old CLEAR_ON_RESUME quirk as the
CLEAR_ON_RESUME quirk sends EC query commands unconditionally. The
behavior is apparently not suitable for firmware that requires
QUERY_HANDSHAKE quirk. Though the QUERY_HANDSHAKE quirk isn't used
now because of the improvement done in the EC transaction state
machine (ec_event_clearing=QUERY), it is the proof that we cannot
send EC query command unconditionally.

So it's time to delete the out-dated CLEAR_ON_RESUME quirk to let the
users to try the newer approach.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=191211
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
hifive-unleashed-5.1
Lv Zheng 2017-01-04 11:17:17 +08:00 committed by Rafael J. Wysocki
parent 566cf877a1
commit 4c237371f2
1 changed files with 0 additions and 53 deletions
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53
drivers/acpi/ec.c
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@ -188,7 +188,6 @@ EXPORT_SYMBOL(first_ec);
static bool boot_ec_is_ecdt = false;
static struct workqueue_struct *ec_query_wq;
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 */
static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */
@ -492,26 +491,6 @@ static inline void __acpi_ec_disable_event(struct acpi_ec *ec)
ec_log_drv("event blocked");
}
/*
* Process _Q events that might have accumulated in the EC.
* Run with locked ec mutex.
*/
static void acpi_ec_clear(struct acpi_ec *ec)
{
int i, status;
u8 value = 0;
for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) {
status = acpi_ec_query(ec, &value);
if (status || !value)
break;
}
if (unlikely(i == ACPI_EC_CLEAR_MAX))
pr_warn("Warning: Maximum of %d stale EC events cleared\n", i);
else
pr_info("%d stale EC events cleared\n", i);
}
static void acpi_ec_enable_event(struct acpi_ec *ec)
{
unsigned long flags;
@ -520,10 +499,6 @@ static void acpi_ec_enable_event(struct acpi_ec *ec)
if (acpi_ec_started(ec))
__acpi_ec_enable_event(ec);
spin_unlock_irqrestore(&ec->lock, flags);
/* Drain additional events if hardware requires that */
if (EC_FLAGS_CLEAR_ON_RESUME)
acpi_ec_clear(ec);
}
#ifdef CONFIG_PM_SLEEP
@ -1740,31 +1715,6 @@ static int ec_flag_query_handshake(const struct dmi_system_id *id)
}
#endif
/*
* 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
* many events are accumulated. (e.g. Samsung Series 5/9 notebooks)
*
* https://bugzilla.kernel.org/show_bug.cgi?id=44161
*
* Ideally, the EC should also be instructed NOT to accumulate events during
* sleep (which Windows seems to do somehow), but the interface to control this
* behaviour is not known at this time.
*
* Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx,
* however it is very likely that other Samsung models are affected.
*
* On systems which don't accumulate _Q events during sleep, this extra check
* should be harmless.
*/
static int ec_clear_on_resume(const struct dmi_system_id *id)
{
pr_debug("Detected system needing EC poll on resume.\n");
EC_FLAGS_CLEAR_ON_RESUME = 1;
ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS;
return 0;
}
/*
* Some ECDTs contain wrong register addresses.
* MSI MS-171F
@ -1782,9 +1732,6 @@ static struct dmi_system_id ec_dmi_table[] __initdata = {
ec_correct_ecdt, "MSI MS-171F", {
DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"),
DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL},
{
ec_clear_on_resume, "Samsung hardware", {
DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL},
{},
};