On Tue, Mar 18, 2025 at 10:00:31PM +0100, Wolfram Sang wrote: > Hi Laurent, > > > > Read out and check the ID registers, so we can bail out if I2C > > > communication does not work or if the device is unknown. > > > > What's the advantage of that, what are you trying to guard against ? > > That a random chip at address 0x2c will be used.
Is that really a problem ? That would only occur with a broken DT, is it worth guarding against a development-time issue with a runtime check that will increase boot time for every user ? > > > Tested on a > > > Renesas GrayHawk board (R-Car V4M) by using a wrong I2C address and by > > > not enabling RuntimePM for the device. > > > > What do you mean by not enabling runtime PM for the device ? > > I left out pm_runtime_get() before regmap_read_bulk(). -- Regards, Laurent Pinchart
