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>
