[PATCH RFC 0/2] gpiolib: of: Introduce hook for missing gpio-ranges

Stefan Wahren stefan.wahren at i2se.com
Wed Mar 9 11:43:44 PST 2022


This patch series tries to provide backward compatibility for DTB which
lacks the gpio-ranges property.

The commit ("pinctrl: msm: fix gpio-hog related boot issues") by Christian
Lamparter already contains a fallback in case the gpio-ranges property
is missing. But this approach doesn't work on BCM2835 with a gpio-hog
defined for the SoC GPIOs.

Based Christian's on explanation i conclude that the fallback must happen
during the gpiochip_add() call and not afterwards. So the approach is to
call an optional hook, which can be implemented in the platform driver.

This series has been tested on Raspberry Pi 3 B Plus.

Stefan Wahren (2):
  gpiolib: of: Introduce hook for missing gpio-ranges
  pinctrl: bcm2835: implement hook for missing gpio-ranges

 drivers/gpio/gpiolib-of.c             |  5 +++++
 drivers/pinctrl/bcm/pinctrl-bcm2835.c | 18 ++++++++++++++++++
 include/linux/gpio/driver.h           | 12 ++++++++++++
 3 files changed, 35 insertions(+)

-- 
2.7.4




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