On Thursday 23 September 2021 22:41:30 Andy Shevchenko wrote: > On Thu, Sep 23, 2021 at 6:28 PM Jonas Dreßler <verdre@xxxxxxx> wrote: > > On 9/22/21 2:50 PM, Jonas Dreßler wrote: > > ... > > > - Just calling mwifiex_write_reg() once and then blocking until the card > > wakes up using my delay-loop doesn't fix the issue, it's actually > > writing multiple times that fixes the issue > > > > These observations sound a lot like writes (and even reads) are actually > > being dropped, don't they? > > It sounds like you're writing into a not ready (fully powered on) device. This reminds me a discussion with Bjorn about CRS response returned after firmware crash / reset when device is not ready yet: https://lore.kernel.org/linux-pci/20210922164803.GA203171@bhelgaas/ Could not be this similar issue? You could check it via reading PCI_VENDOR_ID register from config space. And if it is not valid value then card is not really ready yet. > To check this, try to put a busy loop for reading and check the value > till it gets 0. > > Something like > > unsigned int count = 1000; > > do { > if (mwifiex_read_reg(...) == 0) > break; > } while (--count); > > > -- > With Best Regards, > Andy Shevchenko
