[1/4] Input: ads7846 - convert to devm_ alloc functions

Commit Message

Marco Felsch March 27, 2019, 1:39 p.m. UTC

Convert to devm function to drop the 'no-mem' error handling path and
strip down the remove funciton a bit.

Signed-off-by: Marco Felsch <[e-mail]>
---
 drivers/input/touchscreen/ads7846.c | 37 ++++++++++++-----------------
 1 file changed, 15 insertions(+), 22 deletions(-)

Comments

Dmitry Torokhov Aug. 9, 2019, 4:44 p.m. UTC | #1

On Wed, Mar 27, 2019 at 02:39:24PM +0100, Marco Felsch wrote:
> Convert to devm function to drop the 'no-mem' error handling path and
> strip down the remove funciton a bit.
> 
> Signed-off-by: Marco Felsch <[e-mail]>

I am not fond of partial devm conversions, as this causes reordering in
of freeing resources in unwind path. In this particular case input
device will be unregistered only after majority of the driver structure
is torn down.

If we want to do devm conversion, we need to do a complete one.

Thanks.

Patch

diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c
index a2f45aefce08..5a7a8425d619 100644
--- a/drivers/input/touchscreen/ads7846.c
+++ b/drivers/input/touchscreen/ads7846.c
@@ -1283,13 +1283,17 @@  static int ads7846_probe(struct spi_device *spi)
 	if (err < 0)
 		return err;
 
-	ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL);
-	packet = kzalloc(sizeof(struct ads7846_packet), GFP_KERNEL);
-	input_dev = input_allocate_device();
-	if (!ts || !packet || !input_dev) {
-		err = -ENOMEM;
-		goto err_free_mem;
-	}
+	ts = devm_kzalloc(&spi->dev, sizeof(*ts), GFP_KERNEL);
+	if (!ts)
+		return -ENOMEM;
+
+	packet = devm_kzalloc(&spi->dev, sizeof(*packet), GFP_KERNEL);
+	if (!packet)
+		return -ENOMEM;
+
+	input_dev = devm_input_allocate_device(&spi->dev);
+	if (!input_dev)
+		return -ENOMEM;
 
 	spi_set_drvdata(spi, ts);
 
@@ -1303,10 +1307,8 @@  static int ads7846_probe(struct spi_device *spi)
 	pdata = dev_get_platdata(&spi->dev);
 	if (!pdata) {
 		pdata = ads7846_probe_dt(&spi->dev);
-		if (IS_ERR(pdata)) {
-			err = PTR_ERR(pdata);
-			goto err_free_mem;
-		}
+		if (IS_ERR(pdata))
+			return PTR_ERR(pdata);
 	}
 
 	ts->model = pdata->model ? : 7846;
@@ -1321,7 +1323,7 @@  static int ads7846_probe(struct spi_device *spi)
 		if (pdata->filter_init != NULL) {
 			err = pdata->filter_init(pdata, &ts->filter_data);
 			if (err < 0)
-				goto err_free_mem;
+				return err;
 		}
 		ts->filter = pdata->filter;
 		ts->filter_cleanup = pdata->filter_cleanup;
@@ -1352,7 +1354,6 @@  static int ads7846_probe(struct spi_device *spi)
 
 	input_dev->name = ts->name;
 	input_dev->phys = ts->phys;
-	input_dev->dev.parent = &spi->dev;
 
 	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
 	input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
@@ -1451,10 +1452,7 @@  static int ads7846_probe(struct spi_device *spi)
  err_cleanup_filter:
 	if (ts->filter_cleanup)
 		ts->filter_cleanup(ts->filter_data);
- err_free_mem:
-	input_free_device(input_dev);
-	kfree(packet);
-	kfree(ts);
+
 	return err;
 }
 
@@ -1467,8 +1465,6 @@  static int ads7846_remove(struct spi_device *spi)
 	ads7846_disable(ts);
 	free_irq(ts->spi->irq, ts);
 
-	input_unregister_device(ts->input);
-
 	ads784x_hwmon_unregister(spi, ts);
 
 	regulator_put(ts->reg);
@@ -1484,9 +1480,6 @@  static int ads7846_remove(struct spi_device *spi)
 	if (ts->filter_cleanup)
 		ts->filter_cleanup(ts->filter_data);
 
-	kfree(ts->packet);
-	kfree(ts);
-
 	dev_dbg(&spi->dev, "unregistered touchscreen\n");
 
 	return 0;