Hi Phil, On Di, 2022-06-28 at 20:45 +0100, Phil Edworthy wrote: > Hi, > > The Renesas RZ/V2M SoC (r9a09g011) has a new i2c controller. This series > add the driver. One annoying problem is that the SoC uses a single reset > line for two i2c controllers, and unfortunately one of the controllers > is managed by some firmware, not by Linux. Therefore, the driver just > deasserts the reset. This sounds scary. If the driver is never loaded, and the reset is never deasserted, what happens to the firmware trying to access the other i2c controller? Does it hang? Or write to the reset controller registers to deassert the reset? If so, is there any protection against concurrent access from firmware and reset controller driver? regards Philipp