[resending with Mario's correct address, sorry for the double post] The driver correctly uses the shadow register when asked for the current value of an output gpio. Unfortunately, it does RMW on the gpdat register both when setting a gpio as input and output. These two patches fix that.
Aside: Apparently, the mpc8309 also partially suffers from the errata preventing outputs from being read back - the bits corresponding to gpios 0-7 are always read as 0, while at least the value of gpio10 is correctly reflected when reading gpdat. Which is how I noticed these bugs - I couldn't understand why turning one LED on would turn off another. Rasmus Villemoes (2): gpio: mpc8xxx: don't modify gpdat when setting gpio as input gpio: mpc8xxx: don't do RMW on gpdat register when setting value drivers/gpio/mpc8xxx_gpio.c | 41 ++++++++++++++----------------------- 1 file changed, 15 insertions(+), 26 deletions(-) -- 2.23.0
