diff options
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/ec.c | 81 |
1 files changed, 73 insertions, 8 deletions
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index c385606bbceb..2540870e89f7 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -121,6 +121,7 @@ struct transaction { }; static int acpi_ec_query(struct acpi_ec *ec, u8 *data); +static void advance_transaction(struct acpi_ec *ec); struct acpi_ec *boot_ec, *first_ec; EXPORT_SYMBOL(first_ec); @@ -132,7 +133,7 @@ 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 */ /* -------------------------------------------------------------------------- - * Transaction Management + * EC Registers * -------------------------------------------------------------------------- */ static inline u8 acpi_ec_read_status(struct acpi_ec *ec) @@ -191,6 +192,64 @@ static const char *acpi_ec_cmd_string(u8 cmd) #define acpi_ec_cmd_string(cmd) "UNDEF" #endif +/* -------------------------------------------------------------------------- + * GPE Registers + * -------------------------------------------------------------------------- */ + +static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec) +{ + acpi_event_status gpe_status = 0; + + (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status); + return (gpe_status & ACPI_EVENT_FLAG_SET) ? true : false; +} + +static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) +{ + if (open) + acpi_enable_gpe(NULL, ec->gpe); + else + acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); + if (acpi_ec_is_gpe_raised(ec)) { + /* + * On some platforms, EN=1 writes cannot trigger GPE. So + * software need to manually trigger a pseudo GPE event on + * EN=1 writes. + */ + pr_debug("***** Polling quirk *****\n"); + advance_transaction(ec); + } +} + +static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close) +{ + if (close) + acpi_disable_gpe(NULL, ec->gpe); + else + acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); +} + +static inline void acpi_ec_clear_gpe(struct acpi_ec *ec) +{ + /* + * GPE STS is a W1C register, which means: + * 1. Software can clear it without worrying about clearing other + * GPEs' STS bits when the hardware sets them in parallel. + * 2. As long as software can ensure only clearing it when it is + * set, hardware won't set it in parallel. + * So software can clear GPE in any contexts. + * Warning: do not move the check into advance_transaction() as the + * EC commands will be sent without GPE raised. + */ + if (!acpi_ec_is_gpe_raised(ec)) + return; + acpi_clear_gpe(NULL, ec->gpe); +} + +/* -------------------------------------------------------------------------- + * Transaction Management + * -------------------------------------------------------------------------- */ + static void acpi_ec_submit_query(struct acpi_ec *ec) { if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { @@ -227,6 +286,12 @@ static void advance_transaction(struct acpi_ec *ec) pr_debug("===== %s (%d) =====\n", in_interrupt() ? "IRQ" : "TASK", smp_processor_id()); + /* + * By always clearing STS before handling all indications, we can + * ensure a hardware STS 0->1 change after this clearing can always + * trigger a GPE interrupt. + */ + acpi_ec_clear_gpe(ec); status = acpi_ec_read_status(ec); t = ec->curr; if (!t) @@ -378,7 +443,7 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) /* disable GPE during transaction if storm is detected */ if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) { /* It has to be disabled, so that it doesn't trigger. */ - acpi_disable_gpe(NULL, ec->gpe); + acpi_ec_disable_gpe(ec, false); } status = acpi_ec_transaction_unlocked(ec, t); @@ -386,7 +451,7 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) { msleep(1); /* It is safe to enable the GPE outside of the transaction. */ - acpi_enable_gpe(NULL, ec->gpe); + acpi_ec_enable_gpe(ec, false); } else if (t->irq_count > ec_storm_threshold) { pr_info("GPE storm detected(%d GPEs), " "transactions will use polling mode\n", @@ -693,7 +758,7 @@ static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, spin_lock_irqsave(&ec->lock, flags); advance_transaction(ec); spin_unlock_irqrestore(&ec->lock, flags); - return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE; + return ACPI_INTERRUPT_HANDLED; } /* -------------------------------------------------------------------------- @@ -812,13 +877,13 @@ static int ec_install_handlers(struct acpi_ec *ec) if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags)) return 0; - status = acpi_install_gpe_handler(NULL, ec->gpe, + status = acpi_install_gpe_raw_handler(NULL, ec->gpe, ACPI_GPE_EDGE_TRIGGERED, &acpi_ec_gpe_handler, ec); if (ACPI_FAILURE(status)) return -ENODEV; - acpi_enable_gpe(NULL, ec->gpe); + acpi_ec_enable_gpe(ec, true); status = acpi_install_address_space_handler(ec->handle, ACPI_ADR_SPACE_EC, &acpi_ec_space_handler, @@ -833,7 +898,7 @@ static int ec_install_handlers(struct acpi_ec *ec) pr_err("Fail in evaluating the _REG object" " of EC device. Broken bios is suspected.\n"); } else { - acpi_disable_gpe(NULL, ec->gpe); + acpi_ec_disable_gpe(ec, true); acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler); return -ENODEV; @@ -848,7 +913,7 @@ static void ec_remove_handlers(struct acpi_ec *ec) { if (!test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags)) return; - acpi_disable_gpe(NULL, ec->gpe); + acpi_ec_disable_gpe(ec, true); if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle, ACPI_ADR_SPACE_EC, &acpi_ec_space_handler))) pr_err("failed to remove space handler\n"); |