From 84aecf2d251a3359bc78b7c8e58f54b9fc966e89 Mon Sep 17 00:00:00 2001 From: Jason Gerecke Date: Mon, 9 Sep 2024 13:32:08 -0700 Subject: [PATCH] HID: wacom: Do not warn about dropped packets for first packet The driver currently assumes that the first sequence number it will see is going to be 0. This is not a realiable assumption and can break if, for example, the tablet has already been running for some time prior to the kernel driver connecting to the device. This commit initializes the expected sequence number to -1 and will only print the "Dropped" warning the it has been updated to a non-negative value. Signed-off-by: Jason Gerecke Tested-by: Joshua Dickens Fixes: 6d09085b38e5 ("HID: wacom: Adding Support for new usages") Signed-off-by: Jiri Kosina --- drivers/hid/wacom_wac.c | 6 +++++- drivers/hid/wacom_wac.h | 2 +- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c index 22b0d281ff5ca..b7129cc7c6bf6 100644 --- a/drivers/hid/wacom_wac.c +++ b/drivers/hid/wacom_wac.c @@ -2386,6 +2386,9 @@ static void wacom_wac_pen_usage_mapping(struct hid_device *hdev, wacom_map_usage(input, usage, field, EV_KEY, BTN_STYLUS3, 0); features->quirks &= ~WACOM_QUIRK_PEN_BUTTON3; break; + case WACOM_HID_WD_SEQUENCENUMBER: + wacom_wac->hid_data.sequence_number = -1; + break; } } @@ -2510,7 +2513,8 @@ static void wacom_wac_pen_event(struct hid_device *hdev, struct hid_field *field wacom_wac->hid_data.barrelswitch3 = value; return; case WACOM_HID_WD_SEQUENCENUMBER: - if (wacom_wac->hid_data.sequence_number != value) { + if (wacom_wac->hid_data.sequence_number != value && + wacom_wac->hid_data.sequence_number >= 0) { int sequence_size = field->logical_maximum - field->logical_minimum + 1; int drop_count = (value - wacom_wac->hid_data.sequence_number) % sequence_size; hid_warn(hdev, "Dropped %d packets", drop_count); diff --git a/drivers/hid/wacom_wac.h b/drivers/hid/wacom_wac.h index 55e0c7a9fdcb4..c8803d5c6a71e 100644 --- a/drivers/hid/wacom_wac.h +++ b/drivers/hid/wacom_wac.h @@ -326,7 +326,7 @@ struct hid_data { int bat_connected; int ps_connected; bool pad_input_event_flag; - unsigned short sequence_number; + int sequence_number; ktime_t time_delayed; };