From:   Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
To:     Rob Herring <robh+dt@kernel.org>,
        Frank Rowand <frowand.list@gmail.com>
Cc:     devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Subject: [PATCH v2] scripts/dtc: dtx_diff: remove broken example from help text
Date:   Thu, 13 Jan 2022 09:19:18 +0100
Message-Id: <20220113081918.10387-1-matthias.schiffer@ew.tq-group.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

dtx_diff suggests to use <(...) syntax to pipe two inputs into it, but
this has never worked: The /proc/self/fds/... paths passed by the shell
will fail the `[ -f "${dtx}" ] && [ -r "${dtx}" ]` check in compile_to_dts,
but even with this check removed, the function cannot work: hexdump will
eat up the DTB magic, making the subsequent dtc call fail, as a pipe
cannot be rewound.

Simply remove this broken example, as there is already an alternative one
that works fine.

Fixes: 10eadc253ddf ("dtc: create tool to diff device trees")
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
---
 scripts/dtc/dtx_diff | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/scripts/dtc/dtx_diff b/scripts/dtc/dtx_diff
index d3422ee15e30..f2bbde4bba86 100755
--- a/scripts/dtc/dtx_diff
+++ b/scripts/dtc/dtx_diff
@@ -59,12 +59,8 @@ Otherwise DTx is treated as a dts source file (aka .dts).
    or '/include/' to be processed.
 
    If DTx_1 and DTx_2 are in different architectures, then this script
-   may not work since \${ARCH} is part of the include path.  Two possible
-   workarounds:
-
-      `basename $0` \\
-          <(ARCH=arch_of_dtx_1 `basename $0` DTx_1) \\
-          <(ARCH=arch_of_dtx_2 `basename $0` DTx_2)
+   may not work since \${ARCH} is part of the include path.  The following
+   workaround can be used:
 
       `basename $0` ARCH=arch_of_dtx_1 DTx_1 >tmp_dtx_1.dts
       `basename $0` ARCH=arch_of_dtx_2 DTx_2 >tmp_dtx_2.dts
-- 
2.25.1