From 953c928c24455744d5534679998d129b947a5e04 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>
Date: Mon, 12 Dec 2022 12:52:12 +0100
Subject: udev: rework 60-evdev.rules to be "additive"

We would execute up to four hwdb match patterns (+ the keyboard builtin):
After the first hit, we would skip the other patterns, because of the GOTO="evdev_end"
action.

57bb707d48131f4daad2b1b746eab586eb66b4f3 (rules: Add extended evdev/input match
rules for event nodes with the same name), added an additional match with
":phys:<phys>:ev:<ev>" inserted. This breaks backwards compatibility for user
hwdb patterns, because we quit after the first match.

In general hwdb properties are "additive". We often have a general rule that
matches a wider class and then some specific overrides. E.g. in this particular
case, we have a match for all trackpoints, and then a bunch of model-specific
settings.

So let's change the rules to try all the match patterns and combine the
received properties. We execute builtin-keyboard once at the end, if there was
at least one match.

Fixes #25698. Fixes https://bugzilla.redhat.com/show_bug.cgi?id=2152226.

This also impacts other cases which I think would be very confusing for users.
Since we quit after a first successful match, if we had e.g. a match for
'evdev:input:b*v*p*' in out database, and the user added a match using
'evdev:name:*', which is the approach we document in the .hwdb files and which
users quite often use, it would be silently ignored. What's worse, if we added
our 'evdev:input:b*v*p*' match at a later point, user's match would stop
working. If we combine all the properties, we get more stable behaviour.
---
 rules.d/60-evdev.rules | 25 +++++++++++++++----------
 1 file changed, 15 insertions(+), 10 deletions(-)

diff --git a/rules.d/60-evdev.rules b/rules.d/60-evdev.rules
index 055a62a12d..15483101e7 100644
--- a/rules.d/60-evdev.rules
+++ b/rules.d/60-evdev.rules
@@ -3,23 +3,28 @@
 ACTION=="remove", GOTO="evdev_end"
 KERNEL!="event*", GOTO="evdev_end"
 
-# skip later rules when we find something for this input device
-IMPORT{builtin}="hwdb --subsystem=input --lookup-prefix=evdev:", \
-  IMPORT{builtin}="keyboard", GOTO="evdev_end"
+# Execute the match patterns below, from least-to-most specific.
+
+# Device matching the modalias string (bustype, vendor, product, version, other properties)
+IMPORT{builtin}="hwdb --subsystem=input --lookup-prefix=evdev:",
+  ENV{.HAVE_HWDB_PROPERTIES}="1"
 
 # AT keyboard matching by the machine's DMI data
 DRIVERS=="atkbd", \
   IMPORT{builtin}="hwdb 'evdev:atkbd:$attr{[dmi/id]modalias}'", \
-  IMPORT{builtin}="keyboard", GOTO="evdev_end"
+  ENV{.HAVE_HWDB_PROPERTIES}="1"
 
-# device matching the input device name + properties + the machine's DMI data
+# Device matching the input device name and the machine's DMI data
 KERNELS=="input*", \
-  IMPORT{builtin}="hwdb 'evdev:name:$attr{name}:phys:$attr{phys}:ev:$attr{capabilities/ev}:$attr{[dmi/id]modalias}'", \
-  IMPORT{builtin}="keyboard", GOTO="evdev_end"
+  IMPORT{builtin}="hwdb 'evdev:name:$attr{name}:$attr{[dmi/id]modalias}'", \
+  ENV{.HAVE_HWDB_PROPERTIES}="1"
 
-# device matching the input device name and the machine's DMI data
+# Device matching the input device name + properties + the machine's DMI data
 KERNELS=="input*", \
-  IMPORT{builtin}="hwdb 'evdev:name:$attr{name}:$attr{[dmi/id]modalias}'", \
-  IMPORT{builtin}="keyboard", GOTO="evdev_end"
+  IMPORT{builtin}="hwdb 'evdev:name:$attr{name}:phys:$attr{phys}:ev:$attr{capabilities/ev}:$attr{[dmi/id]modalias}'", \
+  ENV{.HAVE_HWDB_PROPERTIES}="1"
+
+ENV{.HAVE_HWDB_PROPERTIES}=="1", \
+  IMPORT{builtin}="keyboard"
 
 LABEL="evdev_end"
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