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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.c146
1 files changed, 70 insertions, 76 deletions
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 7b4178393e3..06b78e5e33a 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -65,16 +65,18 @@ enum ec_command {
/* EC events */
enum ec_event {
ACPI_EC_EVENT_OBF_1 = 1, /* Output buffer full */
- ACPI_EC_EVENT_IBF_0, /* Input buffer empty */
+ ACPI_EC_EVENT_IBF_0, /* Input buffer empty */
};
#define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */
#define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */
-static enum ec_mode {
- EC_INTR = 1, /* Output buffer full */
- EC_POLL, /* Input buffer empty */
-} acpi_ec_mode = EC_INTR;
+enum {
+ EC_FLAGS_WAIT_GPE = 0, /* Don't check status until GPE arrives */
+ EC_FLAGS_QUERY_PENDING, /* Query is pending */
+ EC_FLAGS_GPE_MODE, /* Expect GPE to be sent for status change */
+ EC_FLAGS_ONLY_IBF_GPE, /* Expect GPE only for IBF = 0 event */
+};
static int acpi_ec_remove(struct acpi_device *device, int type);
static int acpi_ec_start(struct acpi_device *device);
@@ -116,9 +118,8 @@ static struct acpi_ec {
unsigned long command_addr;
unsigned long data_addr;
unsigned long global_lock;
+ unsigned long flags;
struct mutex lock;
- atomic_t query_pending;
- atomic_t event_count;
wait_queue_head_t wait;
struct list_head list;
u8 handlers_installed;
@@ -148,45 +149,54 @@ static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
outb(data, ec->data_addr);
}
-static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event,
- unsigned old_count)
+static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event)
{
- u8 status = acpi_ec_read_status(ec);
- if (old_count == atomic_read(&ec->event_count))
+ if (test_bit(EC_FLAGS_WAIT_GPE, &ec->flags))
return 0;
if (event == ACPI_EC_EVENT_OBF_1) {
- if (status & ACPI_EC_FLAG_OBF)
+ if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
return 1;
} else if (event == ACPI_EC_EVENT_IBF_0) {
- if (!(status & ACPI_EC_FLAG_IBF))
+ if (!(acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF))
return 1;
}
return 0;
}
-static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event,
- unsigned count, int force_poll)
+static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event, int force_poll)
{
- if (unlikely(force_poll) || acpi_ec_mode == EC_POLL) {
+ if (likely(test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) &&
+ likely(!force_poll)) {
+ if (wait_event_timeout(ec->wait, acpi_ec_check_status(ec, event),
+ msecs_to_jiffies(ACPI_EC_DELAY)))
+ return 0;
+ clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
+ if (acpi_ec_check_status(ec, event)) {
+ if (event == ACPI_EC_EVENT_OBF_1) {
+ /* miss OBF = 1 GPE, don't expect it anymore */
+ printk(KERN_INFO PREFIX "missing OBF_1 confirmation,"
+ "switching to degraded mode.\n");
+ set_bit(EC_FLAGS_ONLY_IBF_GPE, &ec->flags);
+ } else {
+ /* missing GPEs, switch back to poll mode */
+ printk(KERN_INFO PREFIX "missing IBF_1 confirmations,"
+ "switch off interrupt mode.\n");
+ clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
+ }
+ return 0;
+ }
+ } else {
unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
+ clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
while (time_before(jiffies, delay)) {
- if (acpi_ec_check_status(ec, event, 0))
+ if (acpi_ec_check_status(ec, event))
return 0;
}
- } else {
- if (wait_event_timeout(ec->wait,
- acpi_ec_check_status(ec, event, count),
- msecs_to_jiffies(ACPI_EC_DELAY)) ||
- acpi_ec_check_status(ec, event, 0)) {
- return 0;
- } else {
- printk(KERN_ERR PREFIX "acpi_ec_wait timeout,"
+ }
+ printk(KERN_ERR PREFIX "acpi_ec_wait timeout,"
" status = %d, expect_event = %d\n",
acpi_ec_read_status(ec), event);
- }
- }
-
return -ETIME;
}
@@ -196,39 +206,42 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
int force_poll)
{
int result = 0;
- unsigned count = atomic_read(&ec->event_count);
+ set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
acpi_ec_write_cmd(ec, command);
for (; wdata_len > 0; --wdata_len) {
- result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, count, force_poll);
+ result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
if (result) {
printk(KERN_ERR PREFIX
"write_cmd timeout, command = %d\n", command);
goto end;
}
- count = atomic_read(&ec->event_count);
+ set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
acpi_ec_write_data(ec, *(wdata++));
}
if (!rdata_len) {
- result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, count, force_poll);
+ result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
if (result) {
printk(KERN_ERR PREFIX
"finish-write timeout, command = %d\n", command);
goto end;
}
- } else if (command == ACPI_EC_COMMAND_QUERY) {
- atomic_set(&ec->query_pending, 0);
- }
+ } else if (command == ACPI_EC_COMMAND_QUERY)
+ clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
for (; rdata_len > 0; --rdata_len) {
- result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, count, force_poll);
+ if (test_bit(EC_FLAGS_ONLY_IBF_GPE, &ec->flags))
+ force_poll = 1;
+ result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, force_poll);
if (result) {
printk(KERN_ERR PREFIX "read timeout, command = %d\n",
command);
goto end;
}
- count = atomic_read(&ec->event_count);
+ /* Don't expect GPE after last read */
+ if (rdata_len > 1)
+ set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
*(rdata++) = acpi_ec_read_data(ec);
}
end:
@@ -258,10 +271,7 @@ static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
}
}
- /* Make sure GPE is enabled before doing transaction */
- acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
-
- status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0, 0);
+ status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0);
if (status) {
printk(KERN_ERR PREFIX
"input buffer is not empty, aborting transaction\n");
@@ -435,9 +445,9 @@ EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
{
- struct acpi_ec_query_handler *handler;
+ struct acpi_ec_query_handler *handler, *tmp;
mutex_lock(&ec->lock);
- list_for_each_entry(handler, &ec->list, node) {
+ list_for_each_entry_safe(handler, tmp, &ec->list, node) {
if (query_bit == handler->query_bit) {
list_del(&handler->node);
kfree(handler);
@@ -476,23 +486,24 @@ static void acpi_ec_gpe_query(void *ec_cxt)
static u32 acpi_ec_gpe_handler(void *data)
{
acpi_status status = AE_OK;
- u8 value;
struct acpi_ec *ec = data;
- atomic_inc(&ec->event_count);
-
- if (acpi_ec_mode == EC_INTR) {
+ clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
+ if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))
wake_up(&ec->wait);
- }
- value = acpi_ec_read_status(ec);
- if ((value & ACPI_EC_FLAG_SCI) && !atomic_read(&ec->query_pending)) {
- atomic_set(&ec->query_pending, 1);
- status =
- acpi_os_execute(OSL_EC_BURST_HANDLER, acpi_ec_gpe_query, ec);
+ if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_SCI) {
+ if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
+ status = acpi_os_execute(OSL_EC_BURST_HANDLER,
+ acpi_ec_gpe_query, ec);
+ } else if (unlikely(!test_bit(EC_FLAGS_GPE_MODE, &ec->flags))) {
+ /* this is non-query, must be confirmation */
+ printk(KERN_INFO PREFIX "non-query interrupt received,"
+ " switching to interrupt mode\n");
+ set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
}
- return status == AE_OK ?
+ return ACPI_SUCCESS(status) ?
ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
}
@@ -641,13 +652,10 @@ static struct acpi_ec *make_acpi_ec(void)
struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
if (!ec)
return NULL;
-
- atomic_set(&ec->query_pending, 1);
- atomic_set(&ec->event_count, 1);
+ ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
mutex_init(&ec->lock);
init_waitqueue_head(&ec->wait);
INIT_LIST_HEAD(&ec->list);
-
return ec;
}
@@ -741,6 +749,8 @@ static int acpi_ec_add(struct acpi_device *device)
acpi_ec_add_fs(device);
printk(KERN_INFO PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
ec->gpe, ec->command_addr, ec->data_addr);
+ printk(KERN_INFO PREFIX "driver started in %s mode\n",
+ (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
return 0;
}
@@ -833,7 +843,7 @@ static int acpi_ec_start(struct acpi_device *device)
ret = ec_install_handlers(ec);
/* EC is fully operational, allow queries */
- atomic_set(&ec->query_pending, 0);
+ clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
return ret;
}
@@ -924,20 +934,4 @@ static void __exit acpi_ec_exit(void)
return;
}
-#endif /* 0 */
-
-static int __init acpi_ec_set_intr_mode(char *str)
-{
- int intr;
-
- if (!get_option(&str, &intr))
- return 0;
-
- acpi_ec_mode = (intr) ? EC_INTR : EC_POLL;
-
- printk(KERN_NOTICE PREFIX "%s mode.\n", intr ? "interrupt" : "polling");
-
- return 1;
-}
-
-__setup("ec_intr=", acpi_ec_set_intr_mode);
+#endif /* 0 */