DRM Driver implementation question

Gareth Williams gareth.williams.jx at renesas.com
Mon Sep 16 13:55:45 UTC 2019

Hi Laurent/Kieran,

I need to upstream a driver for a display controller that within its registers memory region contains registers related to a PWM device. The PWM device is for controlling the backlight of the display.
Ideally, I would like to create a separated driver for the PWM, so that I can re-use "pwm-backlight", but since the registers for the PWM are right in the middle of the registers for the display controller I would need to ioremap the memory region for the PWM registers region twice, once from the display controller driver, and once from the PWM driver.
Do you think that the double ioremap would be acceptable upstream?

Kind Regards,


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