ACPI: EC: auto select interrupt mode

Start in POLL mode, and if we receive confirmation GPE,
switch to INT mode.
If confirmations are not sent, switch back to POLL.

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index a13d69b..727cc08 100644 (file)
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -586,11 +586,6 @@ and is between 256 and 4096 characters. It is defined in the file
 
        eata=           [HW,SCSI]
 
-       ec_intr=        [HW,ACPI] ACPI Embedded Controller interrupt mode
-                       Format: <int>
-                       0: polling mode
-                       non-0: interrupt mode (default)
-
        edd=            [EDD]
                        Format: {"of[f]" | "sk[ipmbr]"}
                        See comment in arch/i386/boot/edd.S

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 5ce90ce..50d55fe 100644 (file)
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -71,14 +71,10 @@ enum ec_event {
 #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 */
 };
 
 static int acpi_ec_remove(struct acpi_device *device, int type);
@@ -169,21 +165,23 @@ static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event)
 
 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) {
-               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))
-                               return 0;
-               }
-       } else {
+       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)) {
+                       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))
+                               return 0;
+               }
        }
        printk(KERN_ERR PREFIX "acpi_ec_wait timeout,"
                               " status = %d, expect_event = %d\n",
@@ -481,18 +479,17 @@ static u32 acpi_ec_gpe_handler(void *data)
        struct acpi_ec *ec = data;
 
        clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
-
-       if (acpi_ec_mode == EC_INTR) {
+       if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))
                wake_up(&ec->wait);
-       }
 
        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)))
+               set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 
-       return status == AE_OK ?
+       return ACPI_SUCCESS(status) ?
            ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 }
 
@@ -923,20 +920,4 @@ 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 */