diff options
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/ec.c | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index 9c40f6715c69..48d4815603e5 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -196,6 +196,7 @@ static struct workqueue_struct *ec_query_wq; 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 */ static int EC_FLAGS_IGNORE_DSDT_GPE; /* Needs ECDT GPE as correction setting */ +static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */ /* -------------------------------------------------------------------------- * Logging/Debugging @@ -501,6 +502,26 @@ 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; @@ -509,6 +530,10 @@ 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 @@ -1782,6 +1807,31 @@ 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 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 @@ -1830,6 +1880,9 @@ static const struct dmi_system_id ec_dmi_table[] __initconst = { ec_honor_ecdt_gpe, "ASUS X580VD", { DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), DMI_MATCH(DMI_PRODUCT_NAME, "X580VD"),}, NULL}, + { + ec_clear_on_resume, "Samsung hardware", { + DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL}, {}, }; |