ACPI / PM: Make messages in acpi_device_set_power() print device names

Modify acpi_device_set_power() so that diagnostic messages printed by
it to the kernel log always contain the name of the device concerned
to make it possible to identify the device that triggered the message
if need be.

Also replace printk(KERN_WARNING ) with dev_warn() everywhere in that
function.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com>

drivers/acpi/device_pm.c

@@ -166,20 +166,20 @@ int acpi_device_set_power(struct acpi_device *device, int state)
 	/* Make sure this is a valid target state */
 
 	if (state == device->power.state) {
-		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at %s\n",
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already in %s\n",
+				  device->pnp.bus_id,
 				  acpi_power_state_string(state)));
 		return 0;
 	}
 
 	if (!device->power.states[state].flags.valid) {
-		printk(KERN_WARNING PREFIX "Device does not support %s\n",
-		       acpi_power_state_string(state));
+		dev_warn(&device->dev, "Power state %s not supported\n",
+			 acpi_power_state_string(state));
 		return -ENODEV;
 	}
 	if (device->parent && (state < device->parent->power.state)) {
-		printk(KERN_WARNING PREFIX
-			      "Cannot set device to a higher-powered"
-			      " state than parent\n");
+		dev_warn(&device->dev,
+			 "Cannot transition to a higher-powered state than parent\n");
 		return -ENODEV;
 	}
 
@@ -192,8 +192,8 @@ int acpi_device_set_power(struct acpi_device *device, int state)
 
 	if (state < device->power.state && state != ACPI_STATE_D0
 	    && device->power.state >= ACPI_STATE_D3_HOT) {
-		printk(KERN_WARNING PREFIX
-			"Cannot transition to non-D0 state from D3\n");
+		dev_warn(&device->dev,
+			 "Cannot transition to non-D0 state from D3\n");
 		return -ENODEV;
 	}
 
@@ -220,10 +220,8 @@ int acpi_device_set_power(struct acpi_device *device, int state)
 
  end:
 	if (result) {
-		printk(KERN_WARNING PREFIX
-			      "Device [%s] failed to transition to %s\n",
-			      device->pnp.bus_id,
-			      acpi_power_state_string(state));
+		dev_warn(&device->dev, "Failed to change power state to %s\n",
+			 acpi_power_state_string(state));
 	} else {
 		device->power.state = state;
 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,