On Thu, Mar 1, 2018 at 12:49 AM, Rodrigo Rivas Costa
[off-list ref] wrote:

On Wed, Feb 28, 2018 at 09:21:15PM +0200, Andy Shevchenko wrote:

quoted

On Wed, Feb 28, 2018 at 8:43 PM, Rodrigo Rivas Costa
[off-list ref] wrote:

quoted

quoted

+       if (input) {

if (!input)
 return;

?

That was because of symmetry, because further patches add more objects.
Then
if (input)
        free(input);
if (battery)
        free(battery);
/* in the future *(
if (input_gyro)
        free(input_gyro);

Sure, the last one can do an early return, but you break symmetry.

The generic APIs when designed properly are NULL aware at freeing resources.

So, it should look like

free(input);
free(battery);
free(input_gyro);

quoted

quoted

+       if (steam) {
+               cancel_work_sync(&steam->work_connect);
+               steam_unregister(steam);

quoted

+               hid_set_drvdata(hdev, NULL);

Hmm.. Doesn't HID do this?

Do you mean the hid_set_drvdata(hdev, NULL)? I'm not sure, I didn't see
that on hid-core.c or hid-generic.c. And a call like this is done in
many modules... so I did the same, just to be sure.

What you are looking for is, AFAIU:

drivers/base/dd.c:902:          dev_set_drvdata(dev, NULL);

quoted

quoted

+       }

if (steam) {
...
       hid_hw_stop(hdev);
...
} else {
       hid_hw_stop(hdev);
}

?

I have no real preference. Your version has two 'if', mine has two 'if'.
What about:

static void steam_remove(struct hid_device *hdev)
{
        struct steam_device *steam = hid_get_drvdata(hdev);

        if (!steam) {
                hid_hw_stop(hdev);
                return;
        }

        if (steam->quirks & STEAM_QUIRK_WIRELESS) {
                hid_info(hdev, "Steam wireless receiver disconnected");
                hid_hw_close(hdev);
        }
        hid_hw_stop(hdev);
        cancel_work_sync(&steam->work_connect);
        steam_unregister(steam);

        hid_set_drvdata(hdev, NULL);

w/o this one.

}

For me my version looks more compact to read, but at the end it's up to you.
Another option split if (steam) variant into helper, and thus

if (steam)
 steam_non_null_device_remove();
else
 hid_hw_stop();

But again, up to you (that's why question mark in the first place above).

-- 
With Best Regards,
Andy Shevchenko