dev_get_drvdata() is called in img_pwm_runtime_resume() before the
driver data is set.
When pm_runtime_enabled() returns false in img_pwm_probe() it calls
img_pwm_runtime_resume() which results in a null pointer access.
This patch fixes the problem by setting the driver data earlier in the
img_pwm_probe() function.
This crash was seen when booting the Imagination Technologies Creator
Ci40 (Marduk) with kernel 5.4 in OpenWrt.
Fixes: e690ae5262 ("pwm: img: Add runtime PM")
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Even in failed case of pm_runtime_get_sync(), the usage_count is
incremented. In order to keep the usage_count with correct value call
appropriate pm_runtime_put().
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
When building with -Wsometimes-uninitialized, Clang warns:
drivers/pwm/pwm-img.c:126:13: error: variable 'timebase' is used
uninitialized whenever 'if' condition is false
[-Werror,-Wsometimes-uninitialized]
The final else if functions as an else; make that explicit so that Clang
understands that timebase cannot be used uninitialized.
Link: https://github.com/ClangBuiltLinux/linux/issues/400
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The power may be disabled during suspend, so implement suspend and
resume callbacks to save and restore register state.
Signed-off-by: Ed Blake <ed.blake@sondrel.com>
[thierry.reding@gmail.com: guard using PM_SLEEP instead of PM]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The PWM hardware on Pistachio platform has a maximum timebase steps
value to 255. To fix it, let's introduce a compatible-specific
data structure to contain the SoC-specific details and use it to
specify a maximum timebase.
Also, let's limit the minimum timebase to 16 steps, to allow a sane
range of duty cycle steps.
Fixes: 277bb6a29e ("pwm: Imagination Technologies PWM DAC driver")
Signed-off-by: Naidu Tellapati <naidu.tellapati@imgtec.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The Pistachio SOC from Imagination Technologies includes a Pulse Width
Modulation DAC which produces 1 to 4 digital bit-outputs which represent
digital waveforms. These PWM outputs are primarily in charge of controlling
backlight LED devices.
Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Naidu Tellapati <Naidu.Tellapati@imgtec.com>
Signed-off-by: Sai Masarapu <Sai.Masarapu@imgtec.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Reviewed-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
[thierry.reding: fixup license header as discussed on list]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
