diff options
author | 2020-12-15 15:33:37 +0100 | |
---|---|---|
committer | 2020-12-15 15:33:37 +0100 | |
commit | 38a0925c5fc89689433f2a2ad415982397cf626e (patch) | |
tree | ce82405d7e9f9746ebfcf6a0c59b05ded15a9907 /drivers/acpi | |
parent | Merge branches 'acpi-apei', 'acpi-misc' and 'acpi-processor' (diff) | |
parent | ACPI: EC: Clean up status flags checks in advance_transaction() (diff) | |
download | linux-38a0925c5fc89689433f2a2ad415982397cf626e.tar.gz linux-38a0925c5fc89689433f2a2ad415982397cf626e.tar.bz2 linux-38a0925c5fc89689433f2a2ad415982397cf626e.zip |
Merge branch 'acpi-ec'
* acpi-ec:
ACPI: EC: Clean up status flags checks in advance_transaction()
ACPI: EC: Untangle error handling in advance_transaction()
ACPI: EC: Simplify error handling in advance_transaction()
ACPI: EC: Rename acpi_ec_is_gpe_raised()
ACPI: EC: Fold acpi_ec_clear_gpe() into its caller
ACPI: EC: Eliminate in_interrupt() usage
Diffstat (limited to 'drivers/acpi')
-rw-r--r-- | drivers/acpi/ec.c | 117 |
1 files changed, 52 insertions, 65 deletions
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index e0cb1bcfffb2..13565629ce0a 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -169,7 +169,7 @@ struct acpi_ec_query { }; static int acpi_ec_query(struct acpi_ec *ec, u8 *data); -static void advance_transaction(struct acpi_ec *ec); +static void advance_transaction(struct acpi_ec *ec, bool interrupt); static void acpi_ec_event_handler(struct work_struct *work); static void acpi_ec_event_processor(struct work_struct *work); @@ -335,12 +335,12 @@ static const char *acpi_ec_cmd_string(u8 cmd) * GPE Registers * -------------------------------------------------------------------------- */ -static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec) +static inline bool acpi_ec_gpe_status_set(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_STATUS_SET) ? true : false; + return !!(gpe_status & ACPI_EVENT_FLAG_STATUS_SET); } static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) @@ -351,14 +351,14 @@ static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) BUG_ON(ec->reference_count < 1); acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); } - if (acpi_ec_is_gpe_raised(ec)) { + if (acpi_ec_gpe_status_set(ec)) { /* * On some platforms, EN=1 writes cannot trigger GPE. So * software need to manually trigger a pseudo GPE event on * EN=1 writes. */ ec_dbg_raw("Polling quirk"); - advance_transaction(ec); + advance_transaction(ec, false); } } @@ -372,23 +372,6 @@ static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close) } } -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 * -------------------------------------------------------------------------- */ @@ -488,7 +471,7 @@ static inline void __acpi_ec_enable_event(struct acpi_ec *ec) * Unconditionally invoke this once after enabling the event * handling mechanism to detect the pending events. */ - advance_transaction(ec); + advance_transaction(ec, false); } static inline void __acpi_ec_disable_event(struct acpi_ec *ec) @@ -632,24 +615,41 @@ static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long f } } -static void advance_transaction(struct acpi_ec *ec) +static void acpi_ec_spurious_interrupt(struct acpi_ec *ec, struct transaction *t) { - struct transaction *t; - u8 status; + if (t->irq_count < ec_storm_threshold) + ++t->irq_count; + + /* Trigger if the threshold is 0 too. */ + if (t->irq_count == ec_storm_threshold) + acpi_ec_mask_events(ec); +} + +static void advance_transaction(struct acpi_ec *ec, bool interrupt) +{ + struct transaction *t = ec->curr; bool wakeup = false; + u8 status; + + ec_dbg_stm("%s (%d)", interrupt ? "IRQ" : "TASK", smp_processor_id()); - ec_dbg_stm("%s (%d)", 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. + * Clear GPE_STS upfront to allow subsequent hardware GPE_STS 0->1 + * changes to always trigger a GPE interrupt. + * + * GPE STS is a W1C register, which means: + * + * 1. Software can clear it without worrying about clearing the 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. */ - if (ec->gpe >= 0) - acpi_ec_clear_gpe(ec); + if (ec->gpe >= 0 && acpi_ec_gpe_status_set(ec)) + acpi_clear_gpe(NULL, ec->gpe); status = acpi_ec_read_status(ec); - t = ec->curr; + /* * Another IRQ or a guarded polling mode advancement is detected, * the next QR_EC submission is then allowed. @@ -661,56 +661,43 @@ static void advance_transaction(struct acpi_ec *ec) clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); acpi_ec_complete_query(ec); } + if (!t) + goto out; } - if (!t) - goto err; + if (t->flags & ACPI_EC_COMMAND_POLL) { if (t->wlen > t->wi) { - if ((status & ACPI_EC_FLAG_IBF) == 0) + if (!(status & ACPI_EC_FLAG_IBF)) acpi_ec_write_data(ec, t->wdata[t->wi++]); - else - goto err; + else if (interrupt && !(status & ACPI_EC_FLAG_SCI)) + acpi_ec_spurious_interrupt(ec, t); } else if (t->rlen > t->ri) { - if ((status & ACPI_EC_FLAG_OBF) == 1) { + if (status & ACPI_EC_FLAG_OBF) { t->rdata[t->ri++] = acpi_ec_read_data(ec); if (t->rlen == t->ri) { ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); + wakeup = true; if (t->command == ACPI_EC_COMMAND_QUERY) ec_dbg_evt("Command(%s) completed by hardware", acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); - wakeup = true; } - } else - goto err; - } else if (t->wlen == t->wi && - (status & ACPI_EC_FLAG_IBF) == 0) { + } else if (interrupt && !(status & ACPI_EC_FLAG_SCI)) { + acpi_ec_spurious_interrupt(ec, t); + } + } else if (t->wlen == t->wi && !(status & ACPI_EC_FLAG_IBF)) { ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); wakeup = true; } - goto out; } else if (!(status & ACPI_EC_FLAG_IBF)) { acpi_ec_write_cmd(ec, t->command); ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); - goto out; - } -err: - /* - * If SCI bit is set, then don't think it's a false IRQ - * otherwise will take a not handled IRQ as a false one. - */ - if (!(status & ACPI_EC_FLAG_SCI)) { - if (in_interrupt() && t) { - if (t->irq_count < ec_storm_threshold) - ++t->irq_count; - /* Allow triggering on 0 threshold */ - if (t->irq_count == ec_storm_threshold) - acpi_ec_mask_events(ec); - } } + out: if (status & ACPI_EC_FLAG_SCI) acpi_ec_submit_query(ec); - if (wakeup && in_interrupt()) + + if (wakeup && interrupt) wake_up(&ec->wait); } @@ -767,7 +754,7 @@ static int ec_poll(struct acpi_ec *ec) if (!ec_guard(ec)) return 0; spin_lock_irqsave(&ec->lock, flags); - advance_transaction(ec); + advance_transaction(ec, false); spin_unlock_irqrestore(&ec->lock, flags); } while (time_before(jiffies, delay)); pr_debug("controller reset, restart transaction\n"); @@ -1216,7 +1203,7 @@ static void acpi_ec_check_event(struct acpi_ec *ec) * taking care of it. */ if (!ec->curr) - advance_transaction(ec); + advance_transaction(ec, false); spin_unlock_irqrestore(&ec->lock, flags); } } @@ -1259,7 +1246,7 @@ static void acpi_ec_handle_interrupt(struct acpi_ec *ec) unsigned long flags; spin_lock_irqsave(&ec->lock, flags); - advance_transaction(ec); + advance_transaction(ec, true); spin_unlock_irqrestore(&ec->lock, flags); } |