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authorLaura Abbott <labbott@redhat.com>2018-02-05 11:20:04 -0800
committerLaura Abbott <labbott@redhat.com>2018-02-05 11:35:34 -0800
commitc41960f76806a516b0c4fd1953779fcd20bc7633 (patch)
treeb71e9707b6ad3b47e8f80bddf5874777d6582b10 /0001-HID-multitouch-Properly-deal-with-Win8-PTP-reports-w.patch
parent622598fecff89da5536a5182e8f9dd5527b8471e (diff)
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Linux v4.15
Diffstat (limited to '0001-HID-multitouch-Properly-deal-with-Win8-PTP-reports-w.patch')
-rw-r--r--0001-HID-multitouch-Properly-deal-with-Win8-PTP-reports-w.patch106
1 files changed, 106 insertions, 0 deletions
diff --git a/0001-HID-multitouch-Properly-deal-with-Win8-PTP-reports-w.patch b/0001-HID-multitouch-Properly-deal-with-Win8-PTP-reports-w.patch
new file mode 100644
index 000000000..e15ec6bb1
--- /dev/null
+++ b/0001-HID-multitouch-Properly-deal-with-Win8-PTP-reports-w.patch
@@ -0,0 +1,106 @@
+From f5c1da991de077420fda17a236342de5a0068f5d Mon Sep 17 00:00:00 2001
+From: Hans de Goede <hdegoede@redhat.com>
+Date: Wed, 22 Nov 2017 12:57:08 +0100
+Subject: [PATCH v2 1/3] HID: multitouch: Properly deal with Win8 PTP reports
+ with 0 touches
+
+The Windows Precision Touchpad spec "Figure 4 Button Only Down and Up"
+and "Table 9 Report Sequence for Button Only Down and Up" indicate
+that the first packet of a (possibly hybrid mode multi-packet) frame
+may contain a contact-count of 0 if only a button is pressed and no
+fingers are detected.
+
+This means that a value of 0 for contact-count is a valid value and
+should be used as expected contact count when it is the first packet
+(num_received == 0), as extra check to make sure that this is the first
+packet of a buttons only frame, we also check that the timestamp is
+different.
+
+Signed-off-by: Hans de Goede <hdegoede@redhat.com>
+Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
+Signed-off-by: Jiri Kosina <jkosina@suse.cz>
+---
+ drivers/hid/hid-multitouch.c | 32 ++++++++++++++++++++++++++++++--
+ 1 file changed, 30 insertions(+), 2 deletions(-)
+
+diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
+index 9ef24b518f12..d8b1cad74faf 100644
+--- a/drivers/hid/hid-multitouch.c
++++ b/drivers/hid/hid-multitouch.c
+@@ -119,6 +119,9 @@ struct mt_device {
+ unsigned long mt_io_flags; /* mt flags (MT_IO_FLAGS_*) */
+ int cc_index; /* contact count field index in the report */
+ int cc_value_index; /* contact count value index in the field */
++ int scantime_index; /* scantime field index in the report */
++ int scantime_val_index; /* scantime value index in the field */
++ int prev_scantime; /* scantime reported in the previous packet */
+ unsigned last_slot_field; /* the last field of a slot */
+ unsigned mt_report_id; /* the report ID of the multitouch device */
+ unsigned long initial_quirks; /* initial quirks state */
+@@ -599,6 +602,12 @@ static int mt_touch_input_mapping(struct hid_device *hdev, struct hid_input *hi,
+ EV_MSC, MSC_TIMESTAMP);
+ input_set_capability(hi->input, EV_MSC, MSC_TIMESTAMP);
+ mt_store_field(usage, td, hi);
++ /* Ignore if indexes are out of bounds. */
++ if (field->index >= field->report->maxfield ||
++ usage->usage_index >= field->report_count)
++ return 1;
++ td->scantime_index = field->index;
++ td->scantime_val_index = usage->usage_index;
+ return 1;
+ case HID_DG_CONTACTCOUNT:
+ /* Ignore if indexes are out of bounds. */
+@@ -855,9 +864,10 @@ static void mt_process_mt_event(struct hid_device *hid, struct hid_field *field,
+ static void mt_touch_report(struct hid_device *hid, struct hid_report *report)
+ {
+ struct mt_device *td = hid_get_drvdata(hid);
++ __s32 cls = td->mtclass.name;
+ struct hid_field *field;
+ unsigned count;
+- int r, n;
++ int r, n, scantime = 0;
+
+ /* sticky fingers release in progress, abort */
+ if (test_and_set_bit(MT_IO_FLAGS_RUNNING, &td->mt_io_flags))
+@@ -867,12 +877,29 @@ static void mt_touch_report(struct hid_device *hid, struct hid_report *report)
+ * Includes multi-packet support where subsequent
+ * packets are sent with zero contactcount.
+ */
++ if (td->scantime_index >= 0) {
++ field = report->field[td->scantime_index];
++ scantime = field->value[td->scantime_val_index];
++ }
+ if (td->cc_index >= 0) {
+ struct hid_field *field = report->field[td->cc_index];
+ int value = field->value[td->cc_value_index];
+- if (value)
++
++ /*
++ * For Win8 PTPs the first packet (td->num_received == 0) may
++ * have a contactcount of 0 if there only is a button event.
++ * We double check that this is not a continuation packet
++ * of a possible multi-packet frame be checking that the
++ * timestamp has changed.
++ */
++ if ((cls == MT_CLS_WIN_8 || cls == MT_CLS_WIN_8_DUAL) &&
++ td->num_received == 0 && td->prev_scantime != scantime)
++ td->num_expected = value;
++ /* A non 0 contact count always indicates a first packet */
++ else if (value)
+ td->num_expected = value;
+ }
++ td->prev_scantime = scantime;
+
+ for (r = 0; r < report->maxfield; r++) {
+ field = report->field[r];
+@@ -1329,6 +1356,7 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
+ td->maxcontact_report_id = -1;
+ td->inputmode_value = MT_INPUTMODE_TOUCHSCREEN;
+ td->cc_index = -1;
++ td->scantime_index = -1;
+ td->mt_report_id = -1;
+ hid_set_drvdata(hdev, td);
+
+--
+2.14.3
+