[PATCH 1/1] doc: correct detection of Sphinx version

[Heinrich Schuchardt]

Starting with Sphinx 1.3 sphinx.ext.pngmath was replaced by
sphinx.ext.imgmath. Unfortunately conf.py does not detect that version
2.4 is greater 1.3. This results in an error

    Could not import extension sphinx.ext.pngmath
    (exception: No module named 'sphinx.ext.pngmath')

in Debian Bullseye which uses Sphinx 2.4 since this month.

Fix the detection of the Sphinx version.

Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
---
The Linux kernel starts recommending Sphinx 2.4. Cf.
https://lkml.org/lkml/2020/4/14/1037
---
 doc/conf.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/conf.py b/doc/conf.py
index 0772fb6f0c..50518a4b2c 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -37,7 +37,7 @@ needs_sphinx = '1.3'
 extensions = ['kerneldoc', 'rstFlatTable', 'kernel_include', 'cdomain', 'kfigure']

 # The name of the math extension changed on Sphinx 1.4
-if major == 1 and minor > 3:
+if major > 1 or major == 1 and minor > 3:
     extensions.append("sphinx.ext.imgmath")
 else:
     extensions.append("sphinx.ext.pngmath")
--
2.26.2