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Diffstat (limited to 'drivers/acpi/ec.c')
-rw-r--r--drivers/acpi/ec.c241
1 files changed, 157 insertions, 84 deletions
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 959d41acc10..a66ab658abb 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -1,11 +1,14 @@
/*
- * ec.c - ACPI Embedded Controller Driver (v2.1)
+ * ec.c - ACPI Embedded Controller Driver (v2.2)
*
- * Copyright (C) 2006-2008 Alexey Starikovskiy <astarikovskiy@suse.de>
- * Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
- * Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
- * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
- * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ * Copyright (C) 2001-2014 Intel Corporation
+ * Author: 2014 Lv Zheng <lv.zheng@intel.com>
+ * 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
+ * 2006 Denis Sadykov <denis.m.sadykov@intel.com>
+ * 2004 Luming Yu <luming.yu@intel.com>
+ * 2001, 2002 Andy Grover <andrew.grover@intel.com>
+ * 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ * Copyright (C) 2008 Alexey Starikovskiy <astarikovskiy@suse.de>
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
@@ -52,6 +55,7 @@
/* EC status register */
#define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */
#define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */
+#define ACPI_EC_FLAG_CMD 0x08 /* Input buffer contains a command */
#define ACPI_EC_FLAG_BURST 0x10 /* burst mode */
#define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */
@@ -67,6 +71,8 @@ enum ec_command {
#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_CLEAR_MAX 100 /* Maximum number of events to query
+ * when trying to clear the EC */
enum {
EC_FLAGS_QUERY_PENDING, /* Query is pending */
@@ -76,6 +82,9 @@ enum {
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);
@@ -107,7 +116,7 @@ struct transaction {
u8 ri;
u8 wlen;
u8 rlen;
- bool done;
+ u8 flags;
};
struct acpi_ec *boot_ec, *first_ec;
@@ -116,6 +125,7 @@ EXPORT_SYMBOL(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 */
/* --------------------------------------------------------------------------
Transaction Management
@@ -124,92 +134,113 @@ static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
{
u8 x = inb(ec->command_addr);
- pr_debug("---> status = 0x%2.2x\n", x);
+ pr_debug("EC_SC(R) = 0x%2.2x "
+ "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d\n",
+ x,
+ !!(x & ACPI_EC_FLAG_SCI),
+ !!(x & ACPI_EC_FLAG_BURST),
+ !!(x & ACPI_EC_FLAG_CMD),
+ !!(x & ACPI_EC_FLAG_IBF),
+ !!(x & ACPI_EC_FLAG_OBF));
return x;
}
static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
{
u8 x = inb(ec->data_addr);
- pr_debug("---> data = 0x%2.2x\n", x);
+ pr_debug("EC_DATA(R) = 0x%2.2x\n", x);
return x;
}
static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
{
- pr_debug("<--- command = 0x%2.2x\n", command);
+ pr_debug("EC_SC(W) = 0x%2.2x\n", command);
outb(command, ec->command_addr);
}
static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
{
- pr_debug("<--- data = 0x%2.2x\n", data);
+ pr_debug("EC_DATA(W) = 0x%2.2x\n", data);
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->lock, flags);
- if (!ec->curr || ec->curr->done)
+ if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE))
ret = 1;
spin_unlock_irqrestore(&ec->lock, flags);
return ret;
}
-static void start_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)
+static bool advance_transaction(struct acpi_ec *ec)
{
- unsigned long flags;
struct transaction *t;
+ u8 status;
+ bool wakeup = false;
- spin_lock_irqsave(&ec->lock, flags);
+ pr_debug("===== %s =====\n", in_interrupt() ? "IRQ" : "TASK");
+ status = acpi_ec_read_status(ec);
t = ec->curr;
if (!t)
- goto unlock;
- 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->done = true;
+ 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;
+ 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 ((status & ACPI_EC_FLAG_IBF) == 0) {
+ acpi_ec_write_cmd(ec, t->command);
+ t->flags |= ACPI_EC_COMMAND_POLL;
} else
goto err;
- } else if (t->wlen == t->wi &&
- (status & ACPI_EC_FLAG_IBF) == 0)
- t->done = true;
- goto unlock;
+ return wakeup;
+ }
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 (in_interrupt() && !(status & ACPI_EC_FLAG_SCI))
- ++t->irq_count;
+ if (!(status & ACPI_EC_FLAG_SCI)) {
+ if (in_interrupt() && t)
+ ++t->irq_count;
+ }
+ return wakeup;
+}
-unlock:
- spin_unlock_irqrestore(&ec->lock, flags);
+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);
+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;
}
@@ -225,15 +256,17 @@ static int ec_poll(struct acpi_ec *ec)
/* 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->lock, flags);
+ (void)advance_transaction(ec);
+ spin_unlock_irqrestore(&ec->lock, flags);
} while (time_before(jiffies, delay));
pr_debug("controller reset, restart transaction\n");
spin_lock_irqsave(&ec->lock, flags);
@@ -265,23 +298,6 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *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;
@@ -302,12 +318,6 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
goto unlock;
}
}
- if (ec_wait_ibf0(ec)) {
- pr_err("input buffer is not empty, "
- "aborting transaction\n");
- status = -ETIME;
- goto end;
- }
pr_debug("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 */
@@ -331,7 +341,6 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
}
pr_debug("transaction end\n");
-end:
if (ec->global_lock)
acpi_release_global_lock(glk);
unlock:
@@ -440,6 +449,27 @@ acpi_handle ec_get_handle(void)
EXPORT_SYMBOL(ec_get_handle);
+/*
+ * 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;
@@ -463,6 +493,10 @@ void acpi_ec_unblock_transactions(void)
mutex_lock(&ec->mutex);
/* 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->mutex);
}
@@ -552,13 +586,18 @@ static void acpi_ec_run(void *cxt)
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 */
@@ -582,7 +621,7 @@ static void acpi_ec_gpe_query(void *ec_cxt)
if (!ec)
return;
mutex_lock(&ec->mutex);
- acpi_ec_sync_query(ec);
+ acpi_ec_sync_query(ec, NULL);
mutex_unlock(&ec->mutex);
}
@@ -601,17 +640,14 @@ static int ec_check_sci(struct acpi_ec *ec, u8 state)
static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
u32 gpe_number, void *data)
{
+ unsigned long flags;
struct acpi_ec *ec = data;
- u8 status = acpi_ec_read_status(ec);
- pr_debug("~~~> interrupt, status:0x%02x\n", status);
-
- advance_transaction(ec, status);
- if (ec_transaction_done(ec) &&
- (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
+ spin_lock_irqsave(&ec->lock, flags);
+ if (advance_transaction(ec))
wake_up(&ec->wait);
- ec_check_sci(ec, acpi_ec_read_status(ec));
- }
+ spin_unlock_irqrestore(&ec->lock, flags);
+ ec_check_sci(ec, acpi_ec_read_status(ec));
return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE;
}
@@ -821,6 +857,13 @@ static int acpi_ec_add(struct acpi_device *device)
/* 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->mutex);
+ acpi_ec_clear(ec);
+ mutex_unlock(&ec->mutex);
+ }
return ret;
}
@@ -922,6 +965,30 @@ static int ec_enlarge_storm_threshold(const struct dmi_system_id *id)
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 ec_dmi_table[] __initdata = {
{
ec_skip_dsdt_scan, "Compal JFL92", {
@@ -965,6 +1032,9 @@ static struct dmi_system_id ec_dmi_table[] __initdata = {
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},
{},
};
@@ -999,8 +1069,10 @@ int __init acpi_ec_ecdt_probe(void)
/* fall through */
}
- if (EC_FLAGS_SKIP_DSDT_SCAN)
+ if (EC_FLAGS_SKIP_DSDT_SCAN) {
+ kfree(saved_ec);
return -ENODEV;
+ }
/* This workaround is needed only on some broken machines,
* which require early EC, but fail to provide ECDT */
@@ -1038,6 +1110,7 @@ install:
}
error:
kfree(boot_ec);
+ kfree(saved_ec);
boot_ec = NULL;
return -ENODEV;
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-10 04:43:04 +0000