CHROMIUM: iwl7000: Fail fast if HW is inaccessible at probe

If the HW is not responding at probe time, fail immediately complaining
about it. Without this, we see that the kernel spends > 100ms trying to
load firmware (even gives an incorrect impression that it actually
loaded a firmware) and do unnecesary processing before concluding that
the device is not accessible:

 INFO kernel: [   34.092678] iwlwifi 0000:01:00.0: enabling device (0000 -> 0002)
 WARNING kernel: [   34.093560] iwlwifi 0000:01:00.0: Direct firmware load for iwl-dbg-cfg.ini failed with error -2
 INFO kernel: [   34.111523] iwlwifi 0000:01:00.0: loaded firmware version 17.318154.0 op_mode iwlmvm
 INFO kernel: [   34.173250] iwlwifi 0000:01:00.0: Detected Intel(R) Dual Band Wireless AC 7265, REV=0xFFFFFFFF
 ERR kernel: [   34.198023] iwlwifi 0000:01:00.0: iwlwifi transaction failed, dumping registers
 ERR kernel: [   34.198044] iwlwifi 0000:01:00.0: iwlwifi device config registers:

Signed-off-by: Rajat Jain <rajatja@google.com>

BUG=b:78586198
TEST=check it fails sooner if HW not accessible.
Change-Id: I4fb5fea510961f18ee1bc1404ee7f85a7c40b22e
Reviewed-on: https://chromium-review.googlesource.com/1038304
Commit-Ready: Kirtika Ruchandani <kirtika@chromium.org>
Tested-by: Rajat Jain <rajatja@chromium.org>
Reviewed-by: Rajat Jain <rajatja@chromium.org>
1 file changed