1 files changed, 65 insertions, 32 deletions

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index ef42316f89f5..cf41f9fc24a7 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -70,7 +70,7 @@ enum ec_command {
 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
 #define ACPI_EC_UDELAY          100     /* Wait 100us before polling EC again */
 
-#define ACPI_EC_STORM_THRESHOLD 20      /* number of false interrupts
+#define ACPI_EC_STORM_THRESHOLD 8       /* number of false interrupts
                                            per one transaction */
 
 enum {
@@ -100,8 +100,11 @@ struct transaction {
         u8 *rdata;
         unsigned short irq_count;
         u8 command;
+        u8 wi;
+        u8 ri;
         u8 wlen;
         u8 rlen;
+        bool done;
 };
 
 static struct acpi_ec {
@@ -178,34 +181,45 @@ static int ec_transaction_done(struct acpi_ec *ec)
         unsigned long flags;
         int ret = 0;
         spin_lock_irqsave(&ec->curr_lock, flags);
-        if (!ec->curr || (!ec->curr->wlen && !ec->curr->rlen))
+        if (!ec->curr || ec->curr->done)
                 ret = 1;
         spin_unlock_irqrestore(&ec->curr_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 gpe_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 > 0) {
-                if ((status & ACPI_EC_FLAG_IBF) == 0) {
-                        acpi_ec_write_data(ec, *(ec->curr->wdata++));
-                        --ec->curr->wlen;
-                } else
-                        /* false interrupt, state didn't change */
-                        ++ec->curr->irq_count;
-
-        } else if (ec->curr->rlen > 0) {
+        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++) = acpi_ec_read_data(ec);
-                        --ec->curr->rlen;
+                        ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
+                        if (ec->curr->rlen == ec->curr->ri)
+                                ec->curr->done = true;
                 } else
-                        /* false interrupt, state didn't change */
-                        ++ec->curr->irq_count;
-        }
+                        goto err;
+        } else if (ec->curr->wlen == ec->curr->wi &&
+                   (status & ACPI_EC_FLAG_IBF) == 0)
+                ec->curr->done = true;
+        goto unlock;
+err:
+        /* false interrupt, state didn't change */
+        ++ec->curr->irq_count;
 unlock:
         spin_unlock_irqrestore(&ec->curr_lock, flags);
 }
@@ -215,6 +229,15 @@ static int acpi_ec_wait(struct acpi_ec *ec)
         if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
                                msecs_to_jiffies(ACPI_EC_DELAY)))
                 return 0;
+        /* try restart command if we get any false interrupts */
+        if (ec->curr->irq_count &&
+            (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
+                pr_debug(PREFIX "controller reset, restart transaction\n");
+                start_transaction(ec);
+                if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
+                                        msecs_to_jiffies(ACPI_EC_DELAY)))
+                        return 0;
+        }
         /* missing GPEs, switch back to poll mode */
         if (printk_ratelimit())
                 pr_info(PREFIX "missing confirmations, "
@@ -239,10 +262,10 @@ static int ec_check_sci(struct acpi_ec *ec, u8 state)
 static int ec_poll(struct acpi_ec *ec)
 {
         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
-        msleep(1);
+        udelay(ACPI_EC_UDELAY);
         while (time_before(jiffies, delay)) {
                 gpe_transaction(ec, acpi_ec_read_status(ec));
-                msleep(1);
+                udelay(ACPI_EC_UDELAY);
                 if (ec_transaction_done(ec))
                         return 0;
         }
@@ -259,14 +282,13 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
         /* disable GPE during transaction if storm is detected */
         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
                 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
-                acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
+                acpi_disable_gpe(NULL, ec->gpe);
         }
         /* start transaction */
         spin_lock_irqsave(&ec->curr_lock, tmp);
         /* following two actions should be kept atomic */
-        t->irq_count = 0;
         ec->curr = t;
-        acpi_ec_write_cmd(ec, ec->curr->command);
+        start_transaction(ec);
         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
         spin_unlock_irqrestore(&ec->curr_lock, tmp);
@@ -283,10 +305,11 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
                 /* check if we received SCI during transaction */
                 ec_check_sci(ec, acpi_ec_read_status(ec));
                 /* it is safe to enable GPE outside of transaction */
-                acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
+                acpi_enable_gpe(NULL, ec->gpe);
         } else if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
                    t->irq_count > ACPI_EC_STORM_THRESHOLD) {
-                pr_debug(PREFIX "GPE storm detected\n");
+                pr_info(PREFIX "GPE storm detected, "
+                        "transactions will use polling mode\n");
                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
         }
         return ret;
@@ -558,17 +581,26 @@ static u32 acpi_ec_gpe_handler(void *data)
         pr_debug(PREFIX "~~~> interrupt\n");
         status = acpi_ec_read_status(ec);
 
-        gpe_transaction(ec, status);
-        if (ec_transaction_done(ec) && (status & ACPI_EC_FLAG_IBF) == 0)
-                wake_up(&ec->wait);
+        if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) {
+                gpe_transaction(ec, status);
+                if (ec_transaction_done(ec) &&
+                    (status & ACPI_EC_FLAG_IBF) == 0)
+                        wake_up(&ec->wait);
+        }
 
         ec_check_sci(ec, status);
         if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
             !test_bit(EC_FLAGS_NO_GPE, &ec->flags)) {
                 /* this is non-query, must be confirmation */
-                if (printk_ratelimit())
-                        pr_info(PREFIX "non-query interrupt received,"
+                if (!test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
+                        if (printk_ratelimit())
+                                pr_info(PREFIX "non-query interrupt received,"
+                                        " switching to interrupt mode\n");
+                } else {
+                        /* hush, STORM switches the mode every transaction */
+                        pr_debug(PREFIX "non-query interrupt received,"
                                 " switching to interrupt mode\n");
+                }
                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
         }
         return ACPI_INTERRUPT_HANDLED;
@@ -736,7 +768,7 @@ static acpi_status
 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 {
         acpi_status status;
-        unsigned long long tmp;
+        unsigned long long tmp = 0;
 
         struct acpi_ec *ec = context;
         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
@@ -751,6 +783,7 @@ ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
                 return status;
         ec->gpe = tmp;
         /* Use the global lock for all EC transactions? */
+        tmp = 0;
         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
         ec->global_lock = tmp;
         ec->handle = handle;
@@ -868,7 +901,7 @@ static int ec_install_handlers(struct acpi_ec *ec)
         if (ACPI_FAILURE(status))
                 return -ENODEV;
         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
-        acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
+        acpi_enable_gpe(NULL, ec->gpe);
         status = acpi_install_address_space_handler(ec->handle,
                                                     ACPI_ADR_SPACE_EC,
                                                     &acpi_ec_space_handler,
@@ -1007,7 +1040,7 @@ static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
         /* Stop using GPE */
         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
-        acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
+        acpi_disable_gpe(NULL, ec->gpe);
         return 0;
 }
 
@@ -1016,7 +1049,7 @@ static int acpi_ec_resume(struct acpi_device *device)
         struct acpi_ec *ec = acpi_driver_data(device);
         /* Enable use of GPE back */
         clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
-        acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
+        acpi_enable_gpe(NULL, ec->gpe);
         return 0;
 }