PCI/ERR: Factor out common dev->driver expressions

Save the struct pci_driver pointer from pdev->driver instead of repeating
it several times.  No functional change.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/pcie/err.c

@@ -49,14 +49,16 @@ static int report_error_detected(struct pci_dev *dev,
 				 pci_channel_state_t state,
 				 enum pci_ers_result *result)
 {
+	struct pci_driver *pdrv;
 	pci_ers_result_t vote;
 	const struct pci_error_handlers *err_handler;
 
 	device_lock(&dev->dev);
+	pdrv = dev->driver;
 	if (!pci_dev_set_io_state(dev, state) ||
-		!dev->driver ||
-		!dev->driver->err_handler ||
-		!dev->driver->err_handler->error_detected) {
+		!pdrv ||
+		!pdrv->err_handler ||
+		!pdrv->err_handler->error_detected) {
 		/*
 		 * If any device in the subtree does not have an error_detected
 		 * callback, PCI_ERS_RESULT_NO_AER_DRIVER prevents subsequent
@@ -70,7 +72,7 @@ static int report_error_detected(struct pci_dev *dev,
 			vote = PCI_ERS_RESULT_NONE;
 		}
 	} else {
-		err_handler = dev->driver->err_handler;
+		err_handler = pdrv->err_handler;
 		vote = err_handler->error_detected(dev, state);
 	}
 	pci_uevent_ers(dev, vote);
@@ -91,16 +93,18 @@ static int report_normal_detected(struct pci_dev *dev, void *data)
 
 static int report_mmio_enabled(struct pci_dev *dev, void *data)
 {
+	struct pci_driver *pdrv;
 	pci_ers_result_t vote, *result = data;
 	const struct pci_error_handlers *err_handler;
 
 	device_lock(&dev->dev);
-	if (!dev->driver ||
-		!dev->driver->err_handler ||
-		!dev->driver->err_handler->mmio_enabled)
+	pdrv = dev->driver;
+	if (!pdrv ||
+		!pdrv->err_handler ||
+		!pdrv->err_handler->mmio_enabled)
 		goto out;
 
-	err_handler = dev->driver->err_handler;
+	err_handler = pdrv->err_handler;
 	vote = err_handler->mmio_enabled(dev);
 	*result = merge_result(*result, vote);
 out:
@@ -110,16 +114,18 @@ static int report_mmio_enabled(struct pci_dev *dev, void *data)
 
 static int report_slot_reset(struct pci_dev *dev, void *data)
 {
+	struct pci_driver *pdrv;
 	pci_ers_result_t vote, *result = data;
 	const struct pci_error_handlers *err_handler;
 
 	device_lock(&dev->dev);
-	if (!dev->driver ||
-		!dev->driver->err_handler ||
-		!dev->driver->err_handler->slot_reset)
+	pdrv = dev->driver;
+	if (!pdrv ||
+		!pdrv->err_handler ||
+		!pdrv->err_handler->slot_reset)
 		goto out;
 
-	err_handler = dev->driver->err_handler;
+	err_handler = pdrv->err_handler;
 	vote = err_handler->slot_reset(dev);
 	*result = merge_result(*result, vote);
 out:
@@ -129,16 +135,18 @@ static int report_slot_reset(struct pci_dev *dev, void *data)
 
 static int report_resume(struct pci_dev *dev, void *data)
 {
+	struct pci_driver *pdrv;
 	const struct pci_error_handlers *err_handler;
 
 	device_lock(&dev->dev);
+	pdrv = dev->driver;
 	if (!pci_dev_set_io_state(dev, pci_channel_io_normal) ||
-		!dev->driver ||
-		!dev->driver->err_handler ||
-		!dev->driver->err_handler->resume)
+		!pdrv ||
+		!pdrv->err_handler ||
+		!pdrv->err_handler->resume)
 		goto out;
 
-	err_handler = dev->driver->err_handler;
+	err_handler = pdrv->err_handler;
 	err_handler->resume(dev);
 out:
 	pci_uevent_ers(dev, PCI_ERS_RESULT_RECOVERED);