HID: core: fix grouping by application

commit f07b3c1da92d ("HID: generic: create one input report per
application type") was effectively the same as MULTI_INPUT:
hidinput->report was never set, so hidinput_match_application()
always returned null.

Fix that by testing against the real application.

Note that this breaks some old eGalax touchscreens that expect MULTI_INPUT
instead of HID_QUIRK_INPUT_PER_APP. Enable this quirk for backward
compatibility on all non-Win8 touchscreens.

link: https://bugzilla.kernel.org/show_bug.cgi?id=200847
link: https://bugzilla.kernel.org/show_bug.cgi?id=200849
link: https://bugs.archlinux.org/task/59699
link: https://github.com/NixOS/nixpkgs/issues/45165
Cc: stable@vger.kernel.org # v4.18+
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
index ac20181..a481eaf 100644 (file)
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c
@@ -1582,6 +1582,7 @@ static struct hid_input *hidinput_allocate(struct hid_device *hid,
        input_dev->dev.parent = &hid->dev;
 
        hidinput->input = input_dev;
+       hidinput->application = application;
        list_add_tail(&hidinput->list, &hid->inputs);
 
        INIT_LIST_HEAD(&hidinput->reports);
@@ -1677,8 +1678,7 @@ static struct hid_input *hidinput_match_application(struct hid_report *report)
        struct hid_input *hidinput;
 
        list_for_each_entry(hidinput, &hid->inputs, list) {
-               if (hidinput->report &&
-                   hidinput->report->application == report->application)
+               if (hidinput->application == report->application)
                        return hidinput;
        }
 

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index 88da991..da954f3 100644 (file)
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -1697,6 +1697,9 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
         */
        hdev->quirks |= HID_QUIRK_INPUT_PER_APP;
 
+       if (id->group != HID_GROUP_MULTITOUCH_WIN_8)
+               hdev->quirks |= HID_QUIRK_MULTI_INPUT;
+
        timer_setup(&td->release_timer, mt_expired_timeout, 0);
 
        ret = hid_parse(hdev);

diff --git a/include/linux/hid.h b/include/linux/hid.h
index 834e646..d44a783 100644 (file)
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -526,6 +526,7 @@ struct hid_input {
        const char *name;
        bool registered;
        struct list_head reports;       /* the list of reports */
+       unsigned int application;       /* application usage for this input */
 };
 
 enum hid_type {