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From: Norihiko Hama <norihiko.hama@alpsalpine.com>
To: Alan Stern <stern@rowland.harvard.edu>
CC: Greg KH <gregkh@linuxfoundation.org>, "linux-usb@vger.kernel.org"
	<linux-usb@vger.kernel.org>, "usb-storage@lists.one-eyed-alien.net"
	<usb-storage@lists.one-eyed-alien.net>, "linux-kernel@vger.kernel.org"
	<linux-kernel@vger.kernel.org>
Subject: RE: [PATCH] usb-storage: Optimize scan delay more precisely
Thread-Topic: [PATCH] usb-storage: Optimize scan delay more precisely
Thread-Index: AQHagAnskZ+PrXZ1a0CyN6BGkMIiXrFLFjOAgAAcfLCAAG5DgIAA1Sdw
Date: Thu, 28 Mar 2024 03:04:47 +0000
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+AD4- On Wed, Mar 27, 2024 at 07:39:55AM +-0000, Norihiko Hama wrote:
+AD4- +AD4- +AD4- Sorry, but module parameters are from the 1990's, we will=
 not go back to that if at all possible as it's not easy to maintain and wi=
ll not work properly for multiple devices.
+AD4- +AD4- +AD4-
+AD4- +AD4- +AD4- I can understand wanting something between 1 and 0 second=
s, but adding yet-another-option isn't probably the best way, sorry.
+AD4- +AD4- 1 second does not meet with performance requirement.
+AD4- +AD4- I have no good idea except module parameter so that we can main=
tain backward compatibility but be configurable out of module.
+AD4- +AD4- Do you have any other better solution?
+AD4-
+AD4- Can you accomplish what you want with a quirk flag?

I think that it's hard to do that because 'quirk' is specified for a device
but it's difficult to identify the devices to make quirk, especially for fu=
ture introduced devices.

Can we change the design of existing 'delay+AF8-use' ?
For example, 'delay+AF8-use' is 32-bit value and the value +ACI-1000 secs+A=
CI- does not make sense to set it,
So if it's set to '1100', it's treated as +ACI-100 / 1000 +AD0- 0.1 sec+ACI=
-. Is this possible?