On 02/20/2018 11:33 AM, Rodrigo Rivas Costa wrote:
> +static void steam_work_connect_cb(struct work_struct *work)
> +{
> + struct steam_device *steam = container_of(work, struct steam_device,
> + work_connect);
> + unsigned long flags;
> + bool connected;
> + int ret;
> +
> + spin_lock_irqsave(&steam->lock, flags);
> + connected = steam->connected;
> + spin_unlock_irqrestore(&steam->lock, flags);
> +
> + if (connected) {
> + if (steam->input) {
> + dbg_hid("%s: already connected\n", __func__);
> + return;
> + }
> + ret = steam_register(steam);
> + if (ret) {
> + hid_err(steam->hdev,
> + "%s:steam_register failed with error %d\n",
> + __func__, ret);
> + return;
> + }
> + } else {
> + steam_unregister(steam);
I think you need synchronization here. You don't want to be in the middle of
processing a HID event or power supply update and have your device freed out
from underneath you.
xpad uses RCU to avoid this race.
> + }
> +}
> +
Regards,
Cameron
