4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Aaron Armstrong Skomra <aaron.skomra@xxxxxxxxx> commit 9ac6678b95b0dd9458a7a6869f46e51cd55a1d84 upstream. Currently the EKR battery remains even after we stop getting information from the device. This can lead to a stale battery persisting indefinitely in userspace. The remote sends a heartbeat every 10 seconds. Delete the battery if we miss two heartbeats (after 21 seconds). Restore the battery once we see a heartbeat again. Signed-off-by: Aaron Skomra <skomra@xxxxxxxxx> Signed-off-by: Aaron Armstrong Skomra <aaron.skomra@xxxxxxxxx> Reviewed-by: Jason Gerecke <jason.gerecke@xxxxxxxxx> Fixes: 9f1015d45f62 ("HID: wacom: EKR: attach the power_supply on first connection") CC: stable@xxxxxxxxxxxxxxx Signed-off-by: Jiri Kosina <jkosina@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/hid/wacom.h | 1 + drivers/hid/wacom_sys.c | 25 +++++++++++++++++++++---- drivers/hid/wacom_wac.c | 1 + drivers/hid/wacom_wac.h | 1 + 4 files changed, 24 insertions(+), 4 deletions(-) --- a/drivers/hid/wacom.h +++ b/drivers/hid/wacom.h @@ -156,6 +156,7 @@ struct wacom_remote { struct input_dev *input; bool registered; struct wacom_battery battery; + ktime_t active_time; } remotes[WACOM_MAX_REMOTES]; }; --- a/drivers/hid/wacom_sys.c +++ b/drivers/hid/wacom_sys.c @@ -2500,6 +2500,18 @@ fail: return; } +static void wacom_remote_destroy_battery(struct wacom *wacom, int index) +{ + struct wacom_remote *remote = wacom->remote; + + if (remote->remotes[index].battery.battery) { + devres_release_group(&wacom->hdev->dev, + &remote->remotes[index].battery.bat_desc); + remote->remotes[index].battery.battery = NULL; + remote->remotes[index].active_time = 0; + } +} + static void wacom_remote_destroy_one(struct wacom *wacom, unsigned int index) { struct wacom_remote *remote = wacom->remote; @@ -2514,9 +2526,7 @@ static void wacom_remote_destroy_one(str remote->remotes[i].registered = false; spin_unlock_irqrestore(&remote->remote_lock, flags); - if (remote->remotes[i].battery.battery) - devres_release_group(&wacom->hdev->dev, - &remote->remotes[i].battery.bat_desc); + wacom_remote_destroy_battery(wacom, i); if (remote->remotes[i].group.name) devres_release_group(&wacom->hdev->dev, @@ -2524,7 +2534,6 @@ static void wacom_remote_destroy_one(str remote->remotes[i].serial = 0; remote->remotes[i].group.name = NULL; - remote->remotes[i].battery.battery = NULL; wacom->led.groups[i].select = WACOM_STATUS_UNKNOWN; } } @@ -2609,6 +2618,9 @@ static int wacom_remote_attach_battery(s if (remote->remotes[index].battery.battery) return 0; + if (!remote->remotes[index].active_time) + return 0; + if (wacom->led.groups[index].select == WACOM_STATUS_UNKNOWN) return 0; @@ -2624,6 +2636,7 @@ static void wacom_remote_work(struct wor { struct wacom *wacom = container_of(work, struct wacom, remote_work); struct wacom_remote *remote = wacom->remote; + ktime_t kt = ktime_get(); struct wacom_remote_data data; unsigned long flags; unsigned int count; @@ -2650,6 +2663,10 @@ static void wacom_remote_work(struct wor serial = data.remote[i].serial; if (data.remote[i].connected) { + if (kt - remote->remotes[i].active_time > WACOM_REMOTE_BATTERY_TIMEOUT + && remote->remotes[i].active_time != 0) + wacom_remote_destroy_battery(wacom, i); + if (remote->remotes[i].serial == serial) { wacom_remote_attach_battery(wacom, i); continue; --- a/drivers/hid/wacom_wac.c +++ b/drivers/hid/wacom_wac.c @@ -1077,6 +1077,7 @@ static int wacom_remote_irq(struct wacom if (index < 0 || !remote->remotes[index].registered) goto out; + remote->remotes[i].active_time = ktime_get(); input = remote->remotes[index].input; input_report_key(input, BTN_0, (data[9] & 0x01)); --- a/drivers/hid/wacom_wac.h +++ b/drivers/hid/wacom_wac.h @@ -19,6 +19,7 @@ #define WACOM_NAME_MAX 64 #define WACOM_MAX_REMOTES 5 #define WACOM_STATUS_UNKNOWN 255 +#define WACOM_REMOTE_BATTERY_TIMEOUT 21000000000ll /* packet length for individual models */ #define WACOM_PKGLEN_BBFUN 9