hid: thingm: reorder calls in thingm_probe

Commit Message

Heiner Kallweit March 1, 2016, 8:24 p.m. UTC

Based on a suggestion from Benjamin move hid_hw_start() after
thingm_version() to avoid potential races.

Signed-off-by: Heiner Kallweit <[e-mail]>
---
 drivers/hid/hid-thingm.c | 31 +++++++++++++------------------
 1 file changed, 13 insertions(+), 18 deletions(-)

Comments

Jiri Kosina March 10, 2016, 9:37 a.m. UTC | #1

On Tue, 1 Mar 2016, Heiner Kallweit wrote:

> Based on a suggestion from Benjamin move hid_hw_start() after
> thingm_version() to avoid potential races.

Please make the changelog much more verbose. Namely please describe the 
exact problems this patch is fixing (IOW why we'd want this patch in the 
first place).

Thanks,

Patch

diff --git a/drivers/hid/hid-thingm.c b/drivers/hid/hid-thingm.c
index f4196ac..847a497 100644
--- a/drivers/hid/hid-thingm.c
+++ b/drivers/hid/hid-thingm.c
@@ -216,17 +216,13 @@  static int thingm_probe(struct hid_device *hdev, const struct hid_device_id *id)
 
 	err = hid_parse(hdev);
 	if (err)
-		goto error;
-
-	err = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
-	if (err)
-		goto error;
+		return err;
 
 	mutex_init(&tdev->lock);
 
 	err = thingm_version(tdev);
 	if (err)
-		goto stop;
+		return err;
 
 	hid_dbg(hdev, "firmware version: %c.%c\n",
 			tdev->version.major, tdev->version.minor);
@@ -237,17 +233,18 @@  static int thingm_probe(struct hid_device *hdev, const struct hid_device_id *id)
 
 	if (!tdev->fwinfo) {
 		hid_err(hdev, "unsupported firmware %c\n", tdev->version.major);
-		err = -ENODEV;
-		goto stop;
+		return -ENODEV;
 	}
 
 	tdev->rgb = devm_kzalloc(&hdev->dev,
 			sizeof(struct thingm_rgb) * tdev->fwinfo->numrgb,
 			GFP_KERNEL);
-	if (!tdev->rgb) {
-		err = -ENOMEM;
-		goto stop;
-	}
+	if (!tdev->rgb)
+		return -ENOMEM;
+
+	err = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
+	if (err)
+		return err;
 
 	for (i = 0; i < tdev->fwinfo->numrgb; ++i) {
 		struct thingm_rgb *rgb = tdev->rgb + i;
@@ -255,15 +252,13 @@  static int thingm_probe(struct hid_device *hdev, const struct hid_device_id *id)
 		rgb->tdev = tdev;
 		rgb->num = tdev->fwinfo->first + i;
 		err = thingm_init_rgb(rgb);
-		if (err)
-			goto stop;
+		if (err) {
+			hid_hw_stop(hdev);
+			return err;
+		}
 	}
 
 	return 0;
-stop:
-	hid_hw_stop(hdev);
-error:
-	return err;
 }
 
 static const struct hid_device_id thingm_table[] = {