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path: root/drivers/acpi/ec.c
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Diffstat (limited to 'drivers/acpi/ec.c')
-rw-r--r--drivers/acpi/ec.c148
1 files changed, 93 insertions, 55 deletions
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index a06d98374705..d7d32c28829b 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -28,6 +28,7 @@
/* Uncomment next line to get verbose printout */
/* #define DEBUG */
+#define pr_fmt(fmt) "ACPI : EC: " fmt
#include <linux/kernel.h>
#include <linux/module.h>
@@ -38,10 +39,9 @@
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
-#include <asm/io.h>
-#include <acpi/acpi_bus.h>
-#include <acpi/acpi_drivers.h>
+#include <linux/acpi.h>
#include <linux/dmi.h>
+#include <asm/io.h>
#include "internal.h"
@@ -49,9 +49,6 @@
#define ACPI_EC_DEVICE_NAME "Embedded Controller"
#define ACPI_EC_FILE_INFO "info"
-#undef PREFIX
-#define PREFIX "ACPI: EC: "
-
/* EC status register */
#define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */
#define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */
@@ -70,6 +67,8 @@ 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 */
@@ -93,10 +92,6 @@ 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);
-
struct acpi_ec_query_handler {
struct list_head node;
acpi_ec_query_func func;
@@ -123,6 +118,7 @@ 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
@@ -131,26 +127,26 @@ 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(PREFIX "---> status = 0x%2.2x\n", x);
+ pr_debug("---> status = 0x%2.2x\n", x);
return x;
}
static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
{
u8 x = inb(ec->data_addr);
- pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
+ pr_debug("---> data = 0x%2.2x\n", x);
return x;
}
static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
{
- pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
+ pr_debug("<--- command = 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(PREFIX "<--- data = 0x%2.2x\n", data);
+ pr_debug("<--- data = 0x%2.2x\n", data);
outb(data, ec->data_addr);
}
@@ -175,9 +171,10 @@ static void start_transaction(struct acpi_ec *ec)
static void advance_transaction(struct acpi_ec *ec, u8 status)
{
unsigned long flags;
- struct transaction *t = ec->curr;
+ struct transaction *t;
spin_lock_irqsave(&ec->lock, flags);
+ t = ec->curr;
if (!t)
goto unlock;
if (t->wlen > t->wi) {
@@ -241,7 +238,7 @@ static int ec_poll(struct acpi_ec *ec)
}
advance_transaction(ec, acpi_ec_read_status(ec));
} while (time_before(jiffies, delay));
- pr_debug(PREFIX "controller reset, restart transaction\n");
+ pr_debug("controller reset, restart transaction\n");
spin_lock_irqsave(&ec->lock, flags);
start_transaction(ec);
spin_unlock_irqrestore(&ec->lock, flags);
@@ -309,12 +306,12 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
}
}
if (ec_wait_ibf0(ec)) {
- pr_err(PREFIX "input buffer is not empty, "
+ pr_err("input buffer is not empty, "
"aborting transaction\n");
status = -ETIME;
goto end;
}
- pr_debug(PREFIX "transaction start (cmd=0x%02x, addr=0x%02x)\n",
+ 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 */
if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
@@ -331,12 +328,12 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
/* It is safe to enable the GPE outside of the transaction. */
acpi_enable_gpe(NULL, ec->gpe);
} else if (t->irq_count > ec_storm_threshold) {
- pr_info(PREFIX "GPE storm detected(%d GPEs), "
+ pr_info("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");
+ pr_debug("transaction end\n");
end:
if (ec->global_lock)
acpi_release_global_lock(glk);
@@ -388,27 +385,6 @@ static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
return acpi_ec_transaction(ec, &t);
}
-/*
- * Externally callable EC access functions. For now, assume 1 EC only
- */
-int ec_burst_enable(void)
-{
- if (!first_ec)
- return -ENODEV;
- return acpi_ec_burst_enable(first_ec);
-}
-
-EXPORT_SYMBOL(ec_burst_enable);
-
-int ec_burst_disable(void)
-{
- if (!first_ec)
- return -ENODEV;
- return acpi_ec_burst_disable(first_ec);
-}
-
-EXPORT_SYMBOL(ec_burst_disable);
-
int ec_read(u8 addr, u8 *val)
{
int err;
@@ -467,6 +443,29 @@ acpi_handle ec_get_handle(void)
EXPORT_SYMBOL(ec_get_handle);
+static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 *data);
+
+/*
+ * Clears stale _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_query_unlocked(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;
@@ -490,6 +489,10 @@ 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);
}
@@ -570,12 +573,12 @@ static void acpi_ec_run(void *cxt)
struct acpi_ec_query_handler *handler = cxt;
if (!handler)
return;
- pr_debug(PREFIX "start query execution\n");
+ pr_debug("start query execution\n");
if (handler->func)
handler->func(handler->data);
else if (handler->handle)
acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
- pr_debug(PREFIX "stop query execution\n");
+ pr_debug("stop query execution\n");
kfree(handler);
}
@@ -593,7 +596,8 @@ static int acpi_ec_sync_query(struct acpi_ec *ec)
if (!copy)
return -ENOMEM;
memcpy(copy, handler, sizeof(*copy));
- pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
+ pr_debug("push query execution (0x%2x) on queue\n",
+ value);
return acpi_os_execute((copy->func) ?
OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
acpi_ec_run, copy);
@@ -616,7 +620,7 @@ static int ec_check_sci(struct acpi_ec *ec, u8 state)
{
if (state & ACPI_EC_FLAG_SCI) {
if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
- pr_debug(PREFIX "push gpe query to the queue\n");
+ pr_debug("push gpe query to the queue\n");
return acpi_os_execute(OSL_NOTIFY_HANDLER,
acpi_ec_gpe_query, ec);
}
@@ -630,7 +634,7 @@ static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
struct acpi_ec *ec = data;
u8 status = acpi_ec_read_status(ec);
- pr_debug(PREFIX "~~~> interrupt, status:0x%02x\n", status);
+ pr_debug("~~~> interrupt, status:0x%02x\n", status);
advance_transaction(ec, status);
if (ec_transaction_done(ec) &&
@@ -776,12 +780,12 @@ static int ec_install_handlers(struct acpi_ec *ec)
* The AE_NOT_FOUND error will be ignored and OS
* continue to initialize EC.
*/
- printk(KERN_ERR "Fail in evaluating the _REG object"
+ pr_err("Fail in evaluating the _REG object"
" of EC device. Broken bios is suspected.\n");
} else {
+ acpi_disable_gpe(NULL, ec->gpe);
acpi_remove_gpe_handler(NULL, ec->gpe,
&acpi_ec_gpe_handler);
- acpi_disable_gpe(NULL, ec->gpe);
return -ENODEV;
}
}
@@ -795,10 +799,10 @@ static void ec_remove_handlers(struct acpi_ec *ec)
acpi_disable_gpe(NULL, ec->gpe);
if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
- pr_err(PREFIX "failed to remove space handler\n");
+ pr_err("failed to remove space handler\n");
if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
&acpi_ec_gpe_handler)))
- pr_err(PREFIX "failed to remove gpe handler\n");
+ pr_err("failed to remove gpe handler\n");
clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
}
@@ -840,13 +844,20 @@ static int acpi_ec_add(struct acpi_device *device)
ret = !!request_region(ec->command_addr, 1, "EC cmd");
WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
- pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
+ pr_info("GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
ec->gpe, ec->command_addr, ec->data_addr);
ret = ec_install_handlers(ec);
/* 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;
}
@@ -931,7 +942,7 @@ static int ec_validate_ecdt(const struct dmi_system_id *id)
/* MSI EC needs special treatment, enable it */
static int ec_flag_msi(const struct dmi_system_id *id)
{
- printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
+ pr_debug("Detected MSI hardware, enabling workarounds.\n");
EC_FLAGS_MSI = 1;
EC_FLAGS_VALIDATE_ECDT = 1;
return 0;
@@ -948,6 +959,30 @@ 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", {
@@ -991,6 +1026,9 @@ 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},
{},
};
@@ -1010,7 +1048,7 @@ int __init acpi_ec_ecdt_probe(void)
status = acpi_get_table(ACPI_SIG_ECDT, 1,
(struct acpi_table_header **)&ecdt_ptr);
if (ACPI_SUCCESS(status)) {
- pr_info(PREFIX "EC description table is found, configuring boot EC\n");
+ pr_info("EC description table is found, configuring boot EC\n");
boot_ec->command_addr = ecdt_ptr->control.address;
boot_ec->data_addr = ecdt_ptr->data.address;
boot_ec->gpe = ecdt_ptr->gpe;
@@ -1030,7 +1068,7 @@ int __init acpi_ec_ecdt_probe(void)
/* This workaround is needed only on some broken machines,
* which require early EC, but fail to provide ECDT */
- printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
+ pr_debug("Look up EC in DSDT\n");
status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
boot_ec, NULL);
/* Check that acpi_get_devices actually find something */
@@ -1042,7 +1080,7 @@ int __init acpi_ec_ecdt_probe(void)
saved_ec->data_addr != boot_ec->data_addr ||
saved_ec->gpe != boot_ec->gpe ||
saved_ec->handle != boot_ec->handle)
- pr_info(PREFIX "ASUSTek keeps feeding us with broken "
+ pr_info("ASUSTek keeps feeding us with broken "
"ECDT tables, which are very hard to workaround. "
"Trying to use DSDT EC info instead. Please send "
"output of acpidump to linux-acpi@vger.kernel.org\n");
generated by cgit v1.2.3 (git 2.0.4) at 2025-09-02 20:57:06 +0000