drm/bridge: waveshare-dsi: Fix signedness bug

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The function drm_of_get_data_lanes_count_ep() returns negative error
codes and dsi->lanes is an unsigned integer, so the check (dsi->lanes <
0) is always impossible.

Make the return value of drm_of_get_data_lanes_count_ep() be assigned to
ret, check for error, and then assign dsi->lanes to ret.

Detected by Smatch:
drivers/gpu/drm/bridge/waveshare-dsi.c:70 ws_bridge_attach_dsi() warn:
unsigned 'dsi->lanes' is never less than zero.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202603060341.hNj0pl9L-lkp@intel.com/
Fixes: fca1142842 ("drm/bridge: waveshare-dsi: Add support for 1..4 DSI data lanes")
Signed-off-by: Ethan Tidmore <ethantidmore06@gmail.com>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Link: https://patch.msgid.link/20260307033245.71666-1-ethantidmore06@gmail.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>

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Ethan Tidmore 2026-03-06 21:32:45 -06:00 • committed by Luca Ceresoli

parent 27a39e135f

commit a469749640

1 changed files with 5 additions and 3 deletions

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drivers/gpu/drm/bridge/waveshare-dsi.c

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