From mboxrd@z Thu Jan 1 00:00:00 1970 MIME-Version: 1.0 In-Reply-To: <599f06db0907200012p3c3c09d1k6e9f50c38fb7a2c0@mail.gmail.com> References: <8ccc8ba40907190814g652f88f6u817a3085b563fdf7@mail.gmail.com> <8ccc8ba40907190858w3b8911cel6b8d64cf22065e71@mail.gmail.com> <599f06db0907200012p3c3c09d1k6e9f50c38fb7a2c0@mail.gmail.com> Date: Mon, 20 Jul 2009 11:07:05 -0400 Message-ID: From: Dan Cross To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [9fans] new usb stack and implicit timeouts Topicbox-Message-UUID: 28e2998c-ead5-11e9-9d60-3106f5b1d025 Pardon me if this is totally ignorant, but can't we just have a ctl message to control a timeout, which applications may then set on their own? On Mon, Jul 20, 2009 at 3:12 AM, Gorka Guardiola wrote: > On Sun, Jul 19, 2009 at 5:58 PM, Francisco J Ballesteros wrote: >> On Sun, Jul 19, 2009 at 5:46 PM, wrote: >>> http://www.beyondlogic.org/usbnutshell/usb6.htm#SetupPacket >>> >> >> IIRC, I think the host controller is responsible for timing out >> requests sent to the device (I refer to setup packets), but my uchi >> does not. In any case, I don't think anyone wants to remove timeouts >> from ctl requests. >> >> > > I am unsure I would remove timeouts even from bulk endpoints. > It is true that some devices (the usb/serial for example) need to > read for an undefined time waiting for data, but I don't think that is > an issue as long > as the timeouts are long enough, doing polling is quite easy. There is > polling in the > lower levels anyway. > > On the other hand, I think smart card readers go for > lunch on a read and may never come > back if there is no timeout. Of course alarm() can be used, but > a timeout makes it simpler. I prefer having to poll on some > cases than having to use signals on others. > > -- > - curiosity sKilled the cat > >