Luca Coelho [off-list ref] writes:

On Sat, 2021-08-21 at 17:04 +0300, Kalle Valo wrote:

quoted

Luca Coelho [off-list ref] writes:

quoted

From: Luca Coelho <redacted>

Export the debug host command framework and add the twt_setup entry.
This will allow external parties to use these debugging features.
More entries can be added later on.

Signed-off-by: Luca Coelho <redacted>

[...]

quoted

--- a/drivers/net/wireless/intel/iwlwifi/Kconfig
+++ b/drivers/net/wireless/intel/iwlwifi/Kconfig

@@ -92,6 +92,12 @@ config IWLWIFI_BCAST_FILTERING

 	  If unsure, don't enable this option, as some programs might
 	  expect incoming broadcasts for their normal operations.
 

+config IWLWIFI_DHC
+	bool "Enable debug host commands"
+	help
+	  This option enables the debug host command API.  It's used
+	  for debugging and validation purposes.
+

Why a new Kconfig option? Those should not be added lightly.

This is a debugging feature that is not really needed in production
kernels, so we prefer to allow it to be removed so we don't waste
resources.

What resources exactly? I would say if the admin or distro maintainer
wants to save on resources he will disable IWLWIFI_DEBUGFS. Why do we
need to have multiple Kconfig options for iwlwifi debugfs interface?

We're publishing this for a few reasons:

1. it will help prevent rebasing mistakes when sending patches upstream
from our internal tree, because a lot of this code is spread around the
driver;

2. in some occasions, we may ask advanced users to enable it so we can
get more data and run more tests in case of tricky bugs;

3. for the specific case of twt_setup, this allows running some TWT
test scenarios with our driver that wouldn't be easily available
otherwise.

Sure, I understand all that. The better debug features we have in
upstream the better. But I don't understand why a new Kconfig option is
needed for DHC feature.

Is it okay to keep it?

In the past Linus has stated his dislike of adding pointless Kconfig
options, with which I strongly agree, and to me it looks like
IWLWIFI_DHC is exactly that. So I'm very hesitant about this.

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