HID: wacom: remove the battery when the EKR is off

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@gmail.com>
Signed-off-by: Aaron Armstrong Skomra <aaron.skomra@wacom.com>
Reviewed-by: Jason Gerecke <jason.gerecke@wacom.com>
Fixes: 9f1015d45f62 ("HID: wacom: EKR: attach the power_supply on first connection")
CC: stable@vger.kernel.org
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/wacom.h b/drivers/hid/wacom.h
index 4da50e19808ef439ba6452c8dcfce3821c54e8a2..166a76c9bcad383dfdeb91a1c31bad74d6a3de12 100644 (file)
--- a/drivers/hid/wacom.h
+++ b/drivers/hid/wacom.h
@@ -150,6 +150,7 @@ struct wacom_remote {
                struct input_dev *input;
                bool registered;
                struct wacom_battery battery;
+               ktime_t active_time;
        } remotes[WACOM_MAX_REMOTES];
 };
 

diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
index 76e5353aca0c7440253d407ceacd41513e18158a..eb833455abd5014ea5d614d25dd88ad15f117e90 100644 (file)
--- a/drivers/hid/wacom_sys.c
+++ b/drivers/hid/wacom_sys.c
@@ -2523,6 +2523,18 @@ 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;
@@ -2537,9 +2549,7 @@ static void wacom_remote_destroy_one(struct wacom *wacom, unsigned int index)
                        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,
@@ -2547,7 +2557,6 @@ static void wacom_remote_destroy_one(struct wacom *wacom, unsigned int index)
 
                        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;
                }
        }
@@ -2632,6 +2641,9 @@ static int wacom_remote_attach_battery(struct wacom *wacom, int index)
        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;
 
@@ -2647,6 +2659,7 @@ static void wacom_remote_work(struct work_struct *work)
 {
        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;
@@ -2673,6 +2686,10 @@ static void wacom_remote_work(struct work_struct *work)
                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;

diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c
index 174bf03908d7c4d108bfeb0c6c494bd3d4cfe93f..6c056f8844e7086a99cea3a8c592f84c91430536 100644 (file)
--- a/drivers/hid/wacom_wac.c
+++ b/drivers/hid/wacom_wac.c
@@ -1134,6 +1134,7 @@ static int wacom_remote_irq(struct wacom_wac *wacom_wac, size_t len)
        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));

diff --git a/drivers/hid/wacom_wac.h b/drivers/hid/wacom_wac.h
index ee21bb260f22f83b85ff1ea66659595aa69d92bd..2e7cc5e7a0cb7fb6ac219ebe93ca56db2503cea6 100644 (file)
--- a/drivers/hid/wacom_wac.h
+++ b/drivers/hid/wacom_wac.h
@@ -13,6 +13,7 @@
 #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