#define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */
#define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */
#define ACPI_EC_MSI_UDELAY 550 /* Wait 550us for MSI EC */
-
-#define ACPI_EC_STORM_THRESHOLD 8 /* number of false interrupts
- per one transaction */
+#define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query
+ * when trying to clear the EC */
enum {
EC_FLAGS_QUERY_PENDING, /* Query is pending */
EC_FLAGS_BLOCKED, /* Transactions are blocked */
};
+#define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */
+#define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */
+
/* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
module_param(ec_delay, uint, 0644);
MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
+/*
+ * If the number of false interrupts per one transaction exceeds
+ * this threshold, will think there is a GPE storm happened and
+ * will disable the GPE for normal transaction.
+ */
+static unsigned int ec_storm_threshold __read_mostly = 8;
+module_param(ec_storm_threshold, uint, 0644);
+MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm");
+
/* If we find an EC via the ECDT, we need to keep a ptr to its context */
/* External interfaces use first EC only, so remember */
typedef int (*acpi_ec_query_func) (void *data);
u8 ri;
u8 wlen;
u8 rlen;
- bool done;
+ u8 flags;
};
struct acpi_ec *boot_ec, *first_ec;
static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
+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
outb(data, ec->data_addr);
}
-static int ec_transaction_done(struct acpi_ec *ec)
+static int ec_transaction_completed(struct acpi_ec *ec)
{
unsigned long flags;
int ret = 0;
spin_lock_irqsave(&ec->curr_lock, flags);
- if (!ec->curr || ec->curr->done)
+ if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE))
ret = 1;
spin_unlock_irqrestore(&ec->curr_lock, flags);
return ret;
}
-static void start_transaction(struct acpi_ec *ec)
+static bool advance_transaction(struct acpi_ec *ec)
{
- ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
- ec->curr->done = false;
- acpi_ec_write_cmd(ec, ec->curr->command);
-}
-
-static void advance_transaction(struct acpi_ec *ec, u8 status)
-{
- unsigned long flags;
- spin_lock_irqsave(&ec->curr_lock, flags);
- if (!ec->curr)
- goto unlock;
- if (ec->curr->wlen > ec->curr->wi) {
- if ((status & ACPI_EC_FLAG_IBF) == 0)
- acpi_ec_write_data(ec,
- ec->curr->wdata[ec->curr->wi++]);
- else
- goto err;
- } else if (ec->curr->rlen > ec->curr->ri) {
- if ((status & ACPI_EC_FLAG_OBF) == 1) {
- ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
- if (ec->curr->rlen == ec->curr->ri)
- ec->curr->done = true;
+ struct transaction *t;
+ u8 status;
+ bool wakeup = false;
+
+ pr_debug(PREFIX "===== %s =====\n", in_interrupt() ? "IRQ" : "TASK");
+ status = acpi_ec_read_status(ec);
+ t = ec->curr;
+ if (!t)
+ goto err;
+ if (t->flags & ACPI_EC_COMMAND_POLL) {
+ if (t->wlen > t->wi) {
+ if ((status & ACPI_EC_FLAG_IBF) == 0)
+ acpi_ec_write_data(ec, t->wdata[t->wi++]);
+ else
+ goto err;
+ } else if (t->rlen > t->ri) {
+ if ((status & ACPI_EC_FLAG_OBF) == 1) {
+ t->rdata[t->ri++] = acpi_ec_read_data(ec);
+ if (t->rlen == t->ri) {
+ t->flags |= ACPI_EC_COMMAND_COMPLETE;
+ if (t->command == ACPI_EC_COMMAND_QUERY)
+ pr_debug("hardware QR_EC completion\n");
+ wakeup = true;
+ }
+ } else
+ goto err;
+ } else if (t->wlen == t->wi &&
+ (status & ACPI_EC_FLAG_IBF) == 0) {
+ t->flags |= ACPI_EC_COMMAND_COMPLETE;
+ wakeup = true;
+ }
+ return wakeup;
+ } else {
+ if (EC_FLAGS_QUERY_HANDSHAKE &&
+ !(status & ACPI_EC_FLAG_SCI) &&
+ (t->command == ACPI_EC_COMMAND_QUERY)) {
+ t->flags |= ACPI_EC_COMMAND_POLL;
+ t->rdata[t->ri++] = 0x00;
+ t->flags |= ACPI_EC_COMMAND_COMPLETE;
+ pr_debug("software QR_EC completion\n");
+ wakeup = true;
+ } else if ((status & ACPI_EC_FLAG_IBF) == 0) {
+ acpi_ec_write_cmd(ec, t->command);
+ t->flags |= ACPI_EC_COMMAND_POLL;
} else
goto err;
- } else if (ec->curr->wlen == ec->curr->wi &&
- (status & ACPI_EC_FLAG_IBF) == 0)
- ec->curr->done = true;
- goto unlock;
+ return wakeup;
+ }
err:
- /* false interrupt, state didn't change */
- if (in_interrupt())
- ++ec->curr->irq_count;
-unlock:
- spin_unlock_irqrestore(&ec->curr_lock, flags);
+ /*
+ * 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)
+ ++t->irq_count;
+ }
+ return wakeup;
}
-static int acpi_ec_sync_query(struct acpi_ec *ec);
+static void start_transaction(struct acpi_ec *ec)
+{
+ ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
+ ec->curr->flags = 0;
+ (void)advance_transaction(ec);
+}
+
+static int acpi_ec_sync_query(struct acpi_ec *ec, u8 *data);
static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
{
if (state & ACPI_EC_FLAG_SCI) {
if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
- return acpi_ec_sync_query(ec);
+ return acpi_ec_sync_query(ec, NULL);
}
return 0;
}
static int ec_poll(struct acpi_ec *ec)
{
unsigned long flags;
- int repeat = 2; /* number of command restarts */
+ int repeat = 5; /* number of command restarts */
while (repeat--) {
unsigned long delay = jiffies +
msecs_to_jiffies(ec_delay);
/* don't sleep with disabled interrupts */
if (EC_FLAGS_MSI || irqs_disabled()) {
udelay(ACPI_EC_MSI_UDELAY);
- if (ec_transaction_done(ec))
+ if (ec_transaction_completed(ec))
return 0;
} else {
if (wait_event_timeout(ec->wait,
- ec_transaction_done(ec),
+ ec_transaction_completed(ec),
msecs_to_jiffies(1)))
return 0;
}
- advance_transaction(ec, acpi_ec_read_status(ec));
+ spin_lock_irqsave(&ec->curr_lock, flags);
+ (void)advance_transaction(ec);
+ spin_unlock_irqrestore(&ec->curr_lock, flags);
} while (time_before(jiffies, delay));
- if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
- break;
pr_debug(PREFIX "controller reset, restart transaction\n");
spin_lock_irqsave(&ec->curr_lock, flags);
start_transaction(ec);
return ret;
}
-static int ec_check_ibf0(struct acpi_ec *ec)
-{
- u8 status = acpi_ec_read_status(ec);
- return (status & ACPI_EC_FLAG_IBF) == 0;
-}
-
-static int ec_wait_ibf0(struct acpi_ec *ec)
-{
- unsigned long delay = jiffies + msecs_to_jiffies(ec_delay);
- /* interrupt wait manually if GPE mode is not active */
- while (time_before(jiffies, delay))
- if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
- msecs_to_jiffies(1)))
- return 0;
- return -ETIME;
-}
-
static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
{
int status;
goto unlock;
}
}
- if (ec_wait_ibf0(ec)) {
- pr_err(PREFIX "input buffer is not empty, "
- "aborting transaction\n");
- status = -ETIME;
- goto end;
- }
- pr_debug(PREFIX "transaction start\n");
+ pr_debug(PREFIX "transaction start (cmd=0x%02x, addr=0x%02x)\n",
+ t->command, t->wdata ? t->wdata[0] : 0);
/* 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. */
msleep(1);
/* It is safe to enable the GPE outside of the transaction. */
acpi_enable_gpe(NULL, ec->gpe);
- } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
- pr_info(PREFIX "GPE storm detected, "
- "transactions will use polling mode\n");
+ } else if (t->irq_count > ec_storm_threshold) {
+ pr_info(PREFIX "GPE storm detected(%d GPEs), "
+ "transactions will use polling mode\n",
+ t->irq_count);
set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
}
pr_debug(PREFIX "transaction end\n");
-end:
if (ec->global_lock)
acpi_release_global_lock(glk);
unlock:
EXPORT_SYMBOL(ec_burst_disable);
-int ec_read(u8 addr, u8 * val)
+int ec_read(u8 addr, u8 *val)
{
int err;
u8 temp_data;
EXPORT_SYMBOL(ec_transaction);
+/*
+ * 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_sync_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);
+}
+
void acpi_ec_block_transactions(void)
{
struct acpi_ec *ec = first_ec;
mutex_lock(&ec->lock);
/* Allow transactions to be carried out again */
clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
+
+ if (EC_FLAGS_CLEAR_ON_RESUME)
+ acpi_ec_clear(ec);
+
mutex_unlock(&ec->lock);
}
kfree(handler);
}
-static int acpi_ec_sync_query(struct acpi_ec *ec)
+static int acpi_ec_sync_query(struct acpi_ec *ec, u8 *data)
{
u8 value = 0;
int status;
struct acpi_ec_query_handler *handler, *copy;
- if ((status = acpi_ec_query_unlocked(ec, &value)))
+
+ status = acpi_ec_query_unlocked(ec, &value);
+ if (data)
+ *data = value;
+ if (status)
return status;
+
list_for_each_entry(handler, &ec->list, node) {
if (value == handler->query_bit) {
/* have custom handler for this bit */
if (!ec)
return;
mutex_lock(&ec->lock);
- acpi_ec_sync_query(ec);
+ acpi_ec_sync_query(ec, NULL);
mutex_unlock(&ec->lock);
}
static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
u32 gpe_number, void *data)
{
+ unsigned long flags;
struct acpi_ec *ec = data;
- pr_debug(PREFIX "~~~> interrupt\n");
-
- advance_transaction(ec, acpi_ec_read_status(ec));
- if (ec_transaction_done(ec) &&
- (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
+ spin_lock_irqsave(&ec->curr_lock, flags);
+ if (advance_transaction(ec))
wake_up(&ec->wait);
- ec_check_sci(ec, acpi_ec_read_status(ec));
- }
+ spin_unlock_irqrestore(&ec->curr_lock, flags);
+ ec_check_sci(ec, acpi_ec_read_status(ec));
return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE;
}
/* EC is fully operational, allow queries */
clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
+
+ /* Clear stale _Q events if hardware might require that */
+ if (EC_FLAGS_CLEAR_ON_RESUME) {
+ mutex_lock(&ec->lock);
+ acpi_ec_clear(ec);
+ mutex_unlock(&ec->lock);
+ }
return ret;
}
return 0;
}
+/*
+ * Clevo M720 notebook actually works ok with IRQ mode, if we lifted
+ * the GPE storm threshold back to 20
+ */
+static int ec_enlarge_storm_threshold(const struct dmi_system_id *id)
+{
+ pr_debug("Setting the EC GPE storm threshold to 20\n");
+ ec_storm_threshold = 20;
+ return 0;
+}
+
+/*
+ * Acer EC firmware refuses to respond QR_EC when SCI_EVT is not set, for
+ * which case, we complete the QR_EC without issuing it to the firmware.
+ * https://bugzilla.kernel.org/show_bug.cgi?id=86211
+ */
+static int ec_flag_query_handshake(const struct dmi_system_id *id)
+{
+ pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n");
+ EC_FLAGS_QUERY_HANDSHAKE = 1;
+ return 0;
+}
+
+/*
+ * 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;
+ return 0;
+}
+
static struct dmi_system_id __initdata ec_dmi_table[] = {
{
ec_skip_dsdt_scan, "Compal JFL92", {
{
ec_validate_ecdt, "ASUS hardware", {
DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL},
+ {
+ ec_enlarge_storm_threshold, "CLEVO hardware", {
+ DMI_MATCH(DMI_SYS_VENDOR, "CLEVO Co."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "M720T/M730T"),}, NULL},
+ {
+ ec_validate_ecdt, "ASUS hardware", {
+ DMI_MATCH(DMI_SYS_VENDOR, "ASUSTek Computer Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),}, NULL},
+ {
+ ec_clear_on_resume, "Samsung hardware", {
+ DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL},
+ {
+ ec_flag_query_handshake, "Acer hardware", {
+ DMI_MATCH(DMI_SYS_VENDOR, "Acer"), }, NULL},
{},
};
-
int __init acpi_ec_ecdt_probe(void)
{
acpi_status status;