[PATCH] HID: usbkbd: return proper error code

[PATCH] HID: usbkbd: return proper error code

[Sudip Mukherjee]

Use proper error code instead of using -1 on failure to allocate
memory. We may use the error code later in the caller.

Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
---
 drivers/hid/usbhid/usbkbd.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/hid/usbhid/usbkbd.c b/drivers/hid/usbhid/usbkbd.c
index 9a332e6..ee53359 100644
--- a/drivers/hid/usbhid/usbkbd.c
+++ b/drivers/hid/usbhid/usbkbd.c
@@ -249,15 +249,15 @@ static void usb_kbd_close(struct input_dev *dev)
 static int usb_kbd_alloc_mem(struct usb_device *dev, struct usb_kbd *kbd)
 {
 	if (!(kbd->irq = usb_alloc_urb(0, GFP_KERNEL)))
-		return -1;
+		return -ENOMEM;
 	if (!(kbd->led = usb_alloc_urb(0, GFP_KERNEL)))
-		return -1;
+		return -ENOMEM;
 	if (!(kbd->new = usb_alloc_coherent(dev, 8, GFP_ATOMIC, &kbd->new_dma)))
-		return -1;
+		return -ENOMEM;
 	if (!(kbd->cr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL)))
-		return -1;
+		return -ENOMEM;
 	if (!(kbd->leds = usb_alloc_coherent(dev, 1, GFP_ATOMIC, &kbd->leds_dma)))
-		return -1;
+		return -ENOMEM;
 
 	return 0;
 }
-- 
1.9.1

Re: [PATCH] HID: usbkbd: return proper error code

[Fabio Estevam]

On Wed, Aug 31, 2016 at 1:28 PM, Sudip Mukherjee
<sudipm.mukherjee@gmail.com> wrote:
> Use proper error code instead of using -1 on failure to allocate
> memory. We may use the error code later in the caller.
>
> Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
> ---
>  drivers/hid/usbhid/usbkbd.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/hid/usbhid/usbkbd.c b/drivers/hid/usbhid/usbkbd.c
> index 9a332e6..ee53359 100644
> --- a/drivers/hid/usbhid/usbkbd.c
> +++ b/drivers/hid/usbhid/usbkbd.c
> @@ -249,15 +249,15 @@ static void usb_kbd_close(struct input_dev *dev)
>  static int usb_kbd_alloc_mem(struct usb_device *dev, struct usb_kbd *kbd)
>  {
>         if (!(kbd->irq = usb_alloc_urb(0, GFP_KERNEL)))
> -               return -1;
> +               return -ENOMEM;

While you are it, the code would look better like this:

kbd->irq = usb_alloc_urb(0, GFP_KERNEL)
if (!kbd->irq)
    return -ENOMEM;

Re: [PATCH] HID: usbkbd: return proper error code

[Sudip Mukherjee]

On Wednesday 31 August 2016 10:03 PM, Fabio Estevam wrote:
> On Wed, Aug 31, 2016 at 1:28 PM, Sudip Mukherjee
> <sudipm.mukherjee@gmail.com> wrote:
>> Use proper error code instead of using -1 on failure to allocate
>> memory. We may use the error code later in the caller.
>>
>> Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
>> ---
>>   drivers/hid/usbhid/usbkbd.c | 10 +++++-----
>>   1 file changed, 5 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/hid/usbhid/usbkbd.c b/drivers/hid/usbhid/usbkbd.c
>> index 9a332e6..ee53359 100644
>> --- a/drivers/hid/usbhid/usbkbd.c
>> +++ b/drivers/hid/usbhid/usbkbd.c
>> @@ -249,15 +249,15 @@ static void usb_kbd_close(struct input_dev *dev)
>>   static int usb_kbd_alloc_mem(struct usb_device *dev, struct usb_kbd *kbd)
>>   {
>>          if (!(kbd->irq = usb_alloc_urb(0, GFP_KERNEL)))
>> -               return -1;
>> +               return -ENOMEM;
>
> While you are it, the code would look better like this:
>
> kbd->irq = usb_alloc_urb(0, GFP_KERNEL)
> if (!kbd->irq)
>      return -ENOMEM;
>

Yes, it will. But that will become two changes in one patch. I will send 
a series with this sent patch and another patch to reorder the assignment.

regards
sudip

Re: [PATCH] HID: usbkbd: return proper error code

[Jiri Kosina]

On Wed, 31 Aug 2016, Sudip Mukherjee wrote:

> Use proper error code instead of using -1 on failure to allocate
> memory. We may use the error code later in the caller.

But we don't. usb_kbd_probe() returns -ENOMEM in case usb_kbd_alloc_mem() 
fails anyway, so I fail to see the point of the change really.

-- 
Jiri Kosina
SUSE Labs

Re: [PATCH] HID: usbkbd: return proper error code

[Sudip Mukherjee]

On Thursday 01 September 2016 04:51 PM, Jiri Kosina wrote:
> On Wed, 31 Aug 2016, Sudip Mukherjee wrote:
>
>> Use proper error code instead of using -1 on failure to allocate
>> memory. We may use the error code later in the caller.
>
> But we don't. usb_kbd_probe() returns -ENOMEM in case usb_kbd_alloc_mem()
> fails anyway, so I fail to see the point of the change really.
>

Well, yes, we don't as of now.
When I was reading the code for something related to my day job I was a 
bit confused with -1 instead of a proper error code. I am sure there 
will be many others like me.
Its fine if you think the change is not needed.

regards
sudip