ACPI: EC: make kernel messages more useful when GPE storm is detected

Make sure we can tell if the GPE storm workaround gets activated,
and avoid flooding the logs afterwards.

http://bugzilla.kernel.org/show_bug.cgi?id=11841
"plenty of line "ACPI: EC: non-query interrupt received,
 switching to interrupt mode" in dmesg"

Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Acked-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 10 insertions, 3 deletions

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 3ef5b796a685..b340e08cf1d9 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -286,7 +286,8 @@ static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
                 acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
         } 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;
@@ -566,9 +567,15 @@ static u32 acpi_ec_gpe_handler(void *data)
         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;