ACPI / EC: Add more debug info and trivial code cleanup

Add more debug info for EC transaction debugging, like the interrupt
status register value, the detail info of a EC transaction.

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 21 insertions, 16 deletions

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 29f349ccf62b..8f8b644bba8d 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -175,30 +175,32 @@ 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;
+
         spin_lock_irqsave(&ec->lock, flags);
-        if (!ec->curr)
+        if (!t)
                 goto unlock;
-        if (ec->curr->wlen > ec->curr->wi) {
+        if (t->wlen > t->wi) {
                 if ((status & ACPI_EC_FLAG_IBF) == 0)
                         acpi_ec_write_data(ec,
-                                ec->curr->wdata[ec->curr->wi++]);
+                                t->wdata[t->wi++]);
                 else
                         goto err;
-        } else if (ec->curr->rlen > ec->curr->ri) {
+        } else if (t->rlen > t->ri) {
                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
-                        ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
-                        if (ec->curr->rlen == ec->curr->ri)
-                                ec->curr->done = true;
+                        t->rdata[t->ri++] = acpi_ec_read_data(ec);
+                        if (t->rlen == t->ri)
+                                t->done = true;
                 } else
                         goto err;
-        } else if (ec->curr->wlen == ec->curr->wi &&
+        } else if (t->wlen == t->wi &&
                    (status & ACPI_EC_FLAG_IBF) == 0)
-                ec->curr->done = true;
+                t->done = true;
         goto unlock;
 err:
         /* false interrupt, state didn't change */
         if (in_interrupt())
-                ++ec->curr->irq_count;
+                ++t->irq_count;
 unlock:
         spin_unlock_irqrestore(&ec->lock, flags);
 }
@@ -310,7 +312,8 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
                 status = -ETIME;
                 goto end;
         }
-        pr_debug(PREFIX "transaction start\n");
+        pr_debug(PREFIX "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)) {
                 /* It has to be disabled, so that it doesn't trigger. */
@@ -326,8 +329,9 @@ 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, "
-                        "transactions will use polling mode\n");
+                pr_info(PREFIX "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");
@@ -403,7 +407,7 @@ int ec_burst_disable(void)
 
 EXPORT_SYMBOL(ec_burst_disable);
 
-int ec_read(u8 addr, u8 * val)
+int ec_read(u8 addr, u8 *val)
 {
         int err;
         u8 temp_data;
@@ -622,10 +626,11 @@ static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
         u32 gpe_number, void *data)
 {
         struct acpi_ec *ec = data;
+        u8 status = acpi_ec_read_status(ec);
 
-        pr_debug(PREFIX "~~~> interrupt\n");
+        pr_debug(PREFIX "~~~> interrupt, status:0x%02x\n", status);
 
-        advance_transaction(ec, acpi_ec_read_status(ec));
+        advance_transaction(ec, status);
         if (ec_transaction_done(ec) &&
             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
                 wake_up(&ec->wait);