From: Jason Gerecke Date: Fri, 8 Sep 2017 00:44:12 +0000 (-0700) Subject: HID: wacom: generic: Send MSC_SERIAL and ABS_MISC when leaving prox X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=993f0d93f8538c15bd5c12a1a9fd74c777efea1b;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git HID: wacom: generic: Send MSC_SERIAL and ABS_MISC when leaving prox The latest generation of pro devices (MobileStudio Pro, 2nd-gen Intuos Pro, Cintiq Pro) send a serial number of '0' whenever the pen is too far away for reliable communication. Userspace defines that a serial number of '0' is invalid, so we need to be careful not to actually forward this value. Additionally, since EMR ISDv4 devices do not support serial numbers or tool IDs, we'd like to not send these events if they aren't necessary. The existing code achieves these goals by adding a check for a non-zero serial number within the wacom_wac_pen_report function. The MSC_SERIAL and ABS_MISC events are only sent if the serial number is non-zero. This code fails, however when the pen for a pro device leaves proximity. When the pen leaves prox and the tablet sends a serial of 0, wacom_wac_pen_event dutifully clears the serial number. When wacom_wac_pen_report is called, it does not send either the MSC_SERIAL of the exiting tool nor an ABS_MISC event. This patch prevents the wacom_wac_pen_event function from clearing an already-set serial number. This ensures that we have the serial number handy when exiting proximity, but requires us to manually clear it afterwards to ensure the driver does not send stale data (e.g. when switching between AES pens that report a serial nubmer of 0 for the first few fully in-proximity packets). Fixes: f85c9dc678 ("HID: wacom: generic: Support tool ID and additional tool types") Cc: stable # v4.10 Signed-off-by: Ping Cheng Signed-off-by: Jason Gerecke Signed-off-by: Jiri Kosina --- diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c index 78d0398904dc..e2ba36da6e20 100644 --- a/drivers/hid/wacom_wac.c +++ b/drivers/hid/wacom_wac.c @@ -2141,8 +2141,10 @@ static void wacom_wac_pen_event(struct hid_device *hdev, struct hid_field *field wacom_wac->hid_data.tipswitch |= value; return; case HID_DG_TOOLSERIALNUMBER: - wacom_wac->serial[0] = (wacom_wac->serial[0] & ~0xFFFFFFFFULL); - wacom_wac->serial[0] |= (__u32)value; + if (value) { + wacom_wac->serial[0] = (wacom_wac->serial[0] & ~0xFFFFFFFFULL); + wacom_wac->serial[0] |= (__u32)value; + } return; case HID_DG_TWIST: /* @@ -2156,15 +2158,17 @@ static void wacom_wac_pen_event(struct hid_device *hdev, struct hid_field *field wacom_wac->hid_data.sense_state = value; return; case WACOM_HID_WD_SERIALHI: - wacom_wac->serial[0] = (wacom_wac->serial[0] & 0xFFFFFFFF); - wacom_wac->serial[0] |= ((__u64)value) << 32; - /* - * Non-USI EMR devices may contain additional tool type - * information here. See WACOM_HID_WD_TOOLTYPE case for - * more details. - */ - if (value >> 20 == 1) { - wacom_wac->id[0] |= value & 0xFFFFF; + if (value) { + wacom_wac->serial[0] = (wacom_wac->serial[0] & 0xFFFFFFFF); + wacom_wac->serial[0] |= ((__u64)value) << 32; + /* + * Non-USI EMR devices may contain additional tool type + * information here. See WACOM_HID_WD_TOOLTYPE case for + * more details. + */ + if (value >> 20 == 1) { + wacom_wac->id[0] |= value & 0xFFFFF; + } } return; case WACOM_HID_WD_TOOLTYPE: @@ -2279,6 +2283,7 @@ static void wacom_wac_pen_report(struct hid_device *hdev, if (!prox) { wacom_wac->tool[0] = 0; wacom_wac->id[0] = 0; + wacom_wac->serial[0] = 0; } }