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From:   =?utf-8?Q?Krzysztof_Ha=C5=82asa?= <khalasa@piap.pl>
To:     Hans Verkuil <hverkuil@xs4all.nl>
Cc:     Mauro Carvalho Chehab <mchehab@kernel.org>,
        linux-media@vger.kernel.org, lkml <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH REPOST] TDA1997x: replace video detection routine
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        <68bd6e41-4c32-240f-aa83-fd2b96929d45@xs4all.nl>
        <m3mtqedfsg.fsf@t19.piap.pl>
Sender: khalasa@piap.pl
Date:   Thu, 22 Jul 2021 08:43:33 +0200
In-Reply-To: <m3mtqedfsg.fsf@t19.piap.pl> ("Krzysztof =?utf-8?Q?Ha=C5=82as?=
 =?utf-8?Q?a=22's?= message of
        "Thu, 22 Jul 2021 08:27:27 +0200")
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Precedence: bulk

Also, I have spotted an interesting loop condition in
drivers/media/v4l2-core/v4l2-dv-timings.c (dated 2013,
d1c65ad6a44b0ff79d2f0bf726fa6fd9248991f4).
It obviously works (unless the table grows to 600+ entries), but I guess
I should make it "standard", shouldn't I?

The first case is pretty normal:
@@ -159,10 +161,10 @@ int v4l2_enum_dv_timings_cap(struct v4l2_enum_dv_timi=
ngs *t,
     u32 i, idx;
=20
     memset(t->reserved, 0, sizeof(t->reserved));
-    for (i =3D idx =3D 0; i < ARRAY_SIZE(timings); i++) {
-        if (v4l2_dv_valid_timings(timings + i, cap) &&
+    for (i =3D idx =3D 0; v4l2_dv_timings_presets[i].bt.width; i++) {
+        if (v4l2_dv_valid_timings(v4l2_dv_timings_presets + i, cap) &&
             idx++ =3D=3D t->index) {
-            t->timings =3D timings[i];
+            t->timings =3D v4l2_dv_timings_presets[i];
             return 0;
         }
     }

This is the interesting part:
@@ -179,10 +181,10 @@ bool v4l2_find_dv_timings_cap(struct v4l2_dv_timings =
*t,
     if (!v4l2_dv_valid_timings(t, cap))
         return false;
=20
-    for (i =3D 0; i < ARRAY_SIZE(timings); i++) {
-        if (v4l2_dv_valid_timings(timings + i, cap) &&
-            v4l2_match_dv_timings(t, timings + i, pclock_delta)) {
-            *t =3D timings[i];
+    for (i =3D 0; i < v4l2_dv_timings_presets[i].bt.width; i++) {
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+        if (v4l2_dv_valid_timings(v4l2_dv_timings_presets + i, cap) &&
+            v4l2_match_dv_timings(t, v4l2_dv_timings_presets + i, pclock_d=
elta)) {
+            *t =3D v4l2_dv_timings_presets[i];
             return true;
         }
     }

--=20
Krzysztof "Chris" Ha=C5=82asa

Sie=C4=87 Badawcza =C5=81ukasiewicz
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