[0/3] pwm: Fix division by 0 issues

Message

Uwe Kleine-König April 1, 2025, 10:28 a.m. UTC

Hello,

triggered by Josh Poimboeuf's patch to fix a warning by objtool due to a
division by zero in the pwm-mediatek driver, I reviewed all pwm drivers
for similar issues.

Josh's patch is resent here, the two additional patches are new. objtool
didn't warn about these even though these are quite similar divisions by
zero. I didn't debug why these were not catched by clang/objtool.

I haven't made up my mind yet if I'll send them for inclusion in
6.15 given that they are new and only build-tested so far. Also the
commits that introduced these problems are already old (v4.12-rc1,
v4.4-rc1 and v5.3-rc1 respectively) and there is no indication this
problem triggers on real hardware.

I'll put them in my for-next branch anyhow for wider exposure. I happily
accept test reports to (hopefully) increase my confidence in these
patches.

Best regards
Uwe

Josh Poimboeuf (1):
  pwm: mediatek: Prevent divide-by-zero in pwm_mediatek_config()

Uwe Kleine-König (2):
  pwm: rcar: Improve register calculation
  pwm: fsl-ftm: Handle clk_get_rate() returning 0

 drivers/pwm/pwm-fsl-ftm.c  |  6 ++++++
 drivers/pwm/pwm-mediatek.c |  8 ++++++--
 drivers/pwm/pwm-rcar.c     | 23 ++++++++++++-----------
 3 files changed, 24 insertions(+), 13 deletions(-)


base-commit: 6df320abbb40654085d7258de33d78481e93ac8d