Skip to content

Commit

Permalink
Merge branch 'acpi-ec'
Browse files Browse the repository at this point in the history 
* 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
  • Loading branch information
Rafael J. Wysocki committed Dec 15, 2020
2 parents 25fe642 + 2a39a30 commit 38a0925
Showing 1 changed file with 52 additions and 65 deletions.
117 changes: 52 additions & 65 deletions drivers/acpi/ec.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -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);

Expand Down Expand Up @@ -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)
Expand All @@ -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);
}
}

Expand All @@ -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
* -------------------------------------------------------------------------- */
Expand Down Expand Up @@ -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)
Expand Down Expand Up @@ -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.
Expand All @@ -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);
}

Expand Down Expand Up @@ -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");
Expand Down Expand Up @@ -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);
}
}
Expand Down Expand Up @@ -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);
}

Expand Down

0 comments on commit 38a0925

Please sign in to comment.