Hi Wolfram, On Thu, Jul 25, 2019 at 09:55:38AM +0200, Wolfram Sang wrote: > Hi Sean, > > thanks for the review! > > On Thu, Jul 25, 2019 at 06:12:02AM +0100, Sean Young wrote: > > On Mon, Jul 22, 2019 at 07:26:31PM +0200, Wolfram Sang wrote: > > > i2c_new_dummy() can fail returning a NULL pointer. The code does not > > > bail out in this case and the returned pointer is blindly used. > > > > I don't see how. The existing code tries to set up the tx part; if > > i2c_new_dummy() return NULL then the rcdev is registered without tx, > > and tx_c is never used. > > Yes, you are totally right. I missed that the send_block function is > also only called iff zilog_init succeeded. Thanks for the heads up and > sorry for the noise. Not at all, thank you for the patch. > > > Convert > > > to devm_i2c_new_dummy_device() which returns an ERR_PTR and also bail > > > out when failing the validity check. > > > > Possibly I was being overly cautious with not bailing out if tx can't > > be registered; moving to devm is probably a good idea. However the > > commit message is misleading, because the existing code has no > > NULL pointer access. > > Yep, I will resend with a proper commit message. Technically, there is > no need to bail out anymore because there is no NULL pointer access. My > tendency is now to not bail out and keep the old behaviour (registering > without tx). What do you think? Since I write this code I've got pretty much every model with this zilog transmitter/receiver, and they all work fine, including different firmware versions. If there is a problem it would be nice to hear about it, and not silently swallow the error. I think. Thanks, Sean
