Re: [PATCH 1/2] mwifiex: Use non-posted PCI register writes

Andy Shevchenko
2021-09-23T19:42:10Z

On Thu, Sep 23, 2021 at 6:28 PM Jonas Dreßler <verdre@v0yd.nl> 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.

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