Input: tca8418-keypad - switch to using managed resources

Let's switch to using devm_*() interfaces to manage our resources,
thus will simplify error unwinding a bit.
Reviewed-by: Alban Bedel <alban.bedel@avionic-design.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/keyboard/tca8418_keypad.c

@@ -111,14 +111,10 @@
 #define KEY_EVENT_VALUE		0x80
 
 struct tca8418_keypad {
-	unsigned int irq;
-	unsigned int row_shift;
-
 	struct i2c_client *client;
 	struct input_dev *input;
 
-	/* Flexible array member, must be at end of struct */
-	unsigned short keymap[];
+	unsigned int row_shift;
 };
 
 /*
@@ -163,6 +159,8 @@ static int tca8418_read_byte(struct tca8418_keypad *keypad_data,
 
 static void tca8418_read_keypad(struct tca8418_keypad *keypad_data)
 {
+	struct input_dev *input = keypad_data->input;
+	unsigned short *keymap = input->keycode;
 	int error, col, row;
 	u8 reg, state, code;
 
@@ -181,9 +179,8 @@ static void tca8418_read_keypad(struct tca8418_keypad *keypad_data)
 		col = (col) ? col - 1 : TCA8418_MAX_COLS - 1;
 
 		code = MATRIX_SCAN_CODE(row, col, keypad_data->row_shift);
-		input_event(keypad_data->input, EV_MSC, MSC_SCAN, code);
-		input_report_key(keypad_data->input,
-				keypad_data->keymap[code], state);
+		input_event(input, EV_MSC, MSC_SCAN, code);
+		input_report_key(input, keymap[code], state);
 
 		/* Read for next loop */
 		error = tca8418_read_byte(keypad_data, REG_KEY_EVENT_A, &reg);
@@ -193,7 +190,7 @@ static void tca8418_read_keypad(struct tca8418_keypad *keypad_data)
 		dev_err(&keypad_data->client->dev,
 			"unable to read REG_KEY_EVENT_A\n");
 
-	input_sync(keypad_data->input);
+	input_sync(input);
 }
 
 /*
@@ -275,6 +272,7 @@ static int tca8418_keypad_probe(struct i2c_client *client,
 	u32 rows = 0, cols = 0;
 	bool rep = false;
 	bool irq_is_gpio = false;
+	int irq;
 	int error, row_shift, max_keys;
 
 	/* Copy the platform data */
@@ -315,9 +313,8 @@ static int tca8418_keypad_probe(struct i2c_client *client,
 	row_shift = get_count_order(cols);
 	max_keys = rows << row_shift;
 
-	/* Allocate memory for keypad_data, keymap and input device */
-	keypad_data = kzalloc(sizeof(*keypad_data) +
-			max_keys * sizeof(keypad_data->keymap[0]), GFP_KERNEL);
+	/* Allocate memory for keypad_data and input device */
+	keypad_data = devm_kzalloc(dev, sizeof(*keypad_data), GFP_KERNEL);
 	if (!keypad_data)
 		return -ENOMEM;
 
@@ -327,29 +324,26 @@ static int tca8418_keypad_probe(struct i2c_client *client,
 	/* Initialize the chip or fail if chip isn't present */
 	error = tca8418_configure(keypad_data, rows, cols);
 	if (error < 0)
-		goto fail1;
+		return error;
 
 	/* Configure input device */
-	input = input_allocate_device();
-	if (!input) {
-		error = -ENOMEM;
-		goto fail1;
-	}
+	input = devm_input_allocate_device(dev);
+	if (!input)
+		return -ENOMEM;
+
 	keypad_data->input = input;
 
 	input->name = client->name;
-	input->dev.parent = &client->dev;
-
 	input->id.bustype = BUS_I2C;
 	input->id.vendor  = 0x0001;
 	input->id.product = 0x001;
 	input->id.version = 0x0001;
 
 	error = matrix_keypad_build_keymap(keymap_data, NULL, rows, cols,
-					   keypad_data->keymap, input);
+					   NULL, input);
 	if (error) {
 		dev_err(dev, "Failed to build keymap\n");
-		goto fail2;
+		return error;
 	}
 
 	if (rep)
@@ -358,10 +352,11 @@ static int tca8418_keypad_probe(struct i2c_client *client,
 
 	input_set_drvdata(input, keypad_data);
 
+	irq = client->irq;
 	if (irq_is_gpio)
-		client->irq = gpio_to_irq(client->irq);
+		irq = gpio_to_irq(irq);
 
-	error = request_threaded_irq(client->irq, NULL, tca8418_irq_handler,
+	error = devm_request_threaded_irq(dev, irq, NULL, tca8418_irq_handler,
 					  IRQF_TRIGGER_FALLING |
 						IRQF_SHARED |
 						IRQF_ONESHOT,
@@ -369,37 +364,15 @@ static int tca8418_keypad_probe(struct i2c_client *client,
 	if (error) {
 		dev_err(dev, "Unable to claim irq %d; error %d\n",
 			client->irq, error);
-		goto fail2;
+		return error;
 	}
 
 	error = input_register_device(input);
 	if (error) {
 		dev_err(dev, "Unable to register input device, error: %d\n",
 			error);
-		goto fail3;
-	}
-
-	i2c_set_clientdata(client, keypad_data);
-	return 0;
-
-fail3:
-	free_irq(client->irq, keypad_data);
-fail2:
-	input_free_device(input);
-fail1:
-	kfree(keypad_data);
 		return error;
-}
-
-static int tca8418_keypad_remove(struct i2c_client *client)
-{
-	struct tca8418_keypad *keypad_data = i2c_get_clientdata(client);
-
-	free_irq(keypad_data->client->irq, keypad_data);
-
-	input_unregister_device(keypad_data->input);
-
-	kfree(keypad_data);
+	}
 
 	return 0;
 }
@@ -425,7 +398,6 @@ static struct i2c_driver tca8418_keypad_driver = {
 		.of_match_table = of_match_ptr(tca8418_dt_ids),
 	},
 	.probe		= tca8418_keypad_probe,
-	.remove		= tca8418_keypad_remove,
 	.id_table	= tca8418_id,
 };