From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Subject: [v2,1/2] USB: serial: ark3116: Remove unused TIOCSSERIAL ioctl case. From: Johan Hovold Message-Id: <20180109115535.GS11344@localhost> Date: Tue, 9 Jan 2018 12:55:35 +0100 To: Mikhail Zaytsev Cc: Johan Hovold , Oliver Neukum , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org List-ID: T24gVHVlLCBKYW4gMDksIDIwMTggYXQgMTI6NDU6MzBBTSArMDMwMCwgTWlraGFpbCBaYXl0c2V2 IHdyb3RlOgo+IE9uIE1vbiwgOCBKYW4gMjAxOCAxNjoyODo1OCArMDEwMCBKb2hhbiBIb3ZvbGQg PGpvaGFuQGtlcm5lbC5vcmc+IHdyb3RlOgo+IAo+ID4gT24gTW9uLCBKYW4gMDgsIDIwMTggYXQg MTE6MzM6MzJBTSArMDEwMCwgT2xpdmVyIE5ldWt1bSB3cm90ZToKPiA+ID4gQW0gU2Ftc3RhZywg ZGVuIDA2LjAxLjIwMTgsIDIwOjE0ICswMzAwIHNjaHJpZWIgTWlraGFpbCBaYXl0c2V2OiAgCj4g PiA+ID4gVGhlIHBhdGNoIHJlbW92ZXMgdW51c2VkIFRJT0NTU0VSSUFMIGlvY3RsIGNhc2UgYW5k IGFkZHMgdGhlIGRlZmF1bHQgYmxvY2sKPiA+ID4gPiB0byB0aGUgc3dpdGNoLiBUaGlzIHdpbGwg bWFrZSB0aGUgaW9jdGwgcmV0dXJuIC1FTk9UVFkgdG8gdXNlciBzcGFjZSAoZS5nLgo+ID4gPiA+ IHNldHNlcmlhbCksIGJlY2F1c2UgVElPQ1NTRVJJQUwgcmVhbGx5IGlzbid0IHN1cHBvcnRlZCBm b3IgdGhlc2UgZGV2aWNlcwo+ID4gPiA+IGN1cnJlbnRseS4gIAo+ID4gPiAKPiA+ID4gSGksCj4g PiA+IAo+ID4gPiB0aGlzIHdpbGwgYnJlYWsgc29mdHdhcmUgdGhhdCBpcyBub3cgcnVubmluZyBv biB0aGVzZSBkZXZpY2VzLAo+ID4gPiB3b24ndCBpdD8gRG8geW91IGtub3cgd2h5IHRob3NlIGRl dmljZXMgYmFzaWNhbGx5IGlnbm9yZSB0aGUKPiA+ID4gaW9jdGw/ICAKPiA+IAo+ID4gWWVhaCwg dGhhdCB3YXMgbXkgaW5pdGlhbCByZWFjdGlvbnMgYXMgd2VsbCwgYnV0IHRoZW4gYWdhaW4sIGFu eSBzYW5lCj4gPiB1c2VyIHNwYWNlIGNhbm5vdCByZWx5IG9uIHRoZXNlIGlvY3RsIGJlaW5nIGlt cGxlbWVudGVkIGZvciBhbGwgdHR5Cj4gPiBkZXZpY2VzLgo+ID4gCj4gPiBJIGRpZCBzb21lIGRp Z2dpbmcgbm93IGFuZCB0aGVzZSAoZHVtbXkpIGlvY3RsIGltcGxlbWVudGF0aW9ucyB3aGVyZQo+ ID4gYWRkZWQgYnkgY29tbWl0IDJmNDMwYjRiYmFlNyAoIlVTQjogYXJrMzExNjogQWRkIFRJT0NH U0VSSUFMIGFuZAo+ID4gVElPQ1NTRVJJQUwgaW9jdGwgY2FsbHMuIikgYmFjayBpbiAyMDA2LiAg VGhpcyBpbiB0dXJuIGFwcGVhcnMgdG8gaGF2ZQo+ID4gYmVlbiB0cmlnZ2VyZWQgYnkgYSBjaGFu Z2UgaW4gYSB1c2VyIHNwYWNlIHRvb2wsIHd2ZGlhbCwgd2hpY2ggc3RhcnRlZAo+ID4gZXJyb3Jp bmcgb3V0IGlmIGVpdGhlciB3YXMgbWlzc2luZy4KPiA+IAo+ID4gSSBmb3VuZCBhIGNvdXBsZSBv ZiBidWcgcmVwb3J0cyBhYm91dCB0aGF0IHRocm91Z2ggZ29vZ2xlLCBhbmQgbG9va2luZwo+ID4g YXQgdGhlIHd2c3RyZWFtcyAobGlicmFyeSkgY29kZSBub3csIGl0IGxvb2tzIGxpa2UgdGhlIGlz c3VlIGhhcyBpbmRlZWQKPiA+IGJlZW4gcmVzb2x2ZWQgYnkgaGFuZGxpbmcgZXJyb3JzIG1vcmUg Z3JhY2VmdWxseSAoZS5nLiBqdXN0IGxvZ2dpbmcKPiA+IHRoZW0pLgo+ID4gCj4gPiBTbyBJJ20g d2lsbGluZyB0byBnaXZlIHRoaXMgYSB0cnksIGFuZCBpZiBhbnlvbmUgY29tcGxhaW5zIGxhdGVy IHdlIGFkZAo+ID4gYmFjayAob3IgaW1wbGVtZW50KSBUSU9DU1NFUklBTC4KPiA+IAo+IAo+IFRo YW5rcyBKb2hhbi4gSSBsb29rZWQgdGhlIGNvbW1pdCAyZjQzMGI0YmJhZTcuIEF1dGhvciBqdXN0 IGRpZCBhIGN1dCduJ3Bhc3RlCj4gIGZyb20gb3RoZXIgVVNCIHNlcmlhbCBkcml2ZXJzLiBJIHRo aW5rIHRoYXQgaXQgd291bGQgYmUgYmV0dGVyIHJlbW92ZQo+IHRoZSBUSU9DR1NFUklBTCBpbXBs ZW1lbnRhdGlvbiB0b28uCgpJJ3ZlIGFwcGxpZWQgdGhpcyBvbmUgbm93IGFmdGVyIGFkZGluZyBz b21lIG9mIHRoZSBiYWNrc3RvcnkgZnJvbSBhYm92ZQp0byB0aGUgY29tbWl0IG1lc3NhZ2UuCgpU aGFua3MsCkpvaGFuCi0tLQpUbyB1bnN1YnNjcmliZSBmcm9tIHRoaXMgbGlzdDogc2VuZCB0aGUg bGluZSAidW5zdWJzY3JpYmUgbGludXgtdXNiIiBpbgp0aGUgYm9keSBvZiBhIG1lc3NhZ2UgdG8g bWFqb3Jkb21vQHZnZXIua2VybmVsLm9yZwpNb3JlIG1ham9yZG9tbyBpbmZvIGF0ICBodHRwOi8v dmdlci5rZXJuZWwub3JnL21ham9yZG9tby1pbmZvLmh0bWwK From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754957AbeAILzl (ORCPT + 1 other); Tue, 9 Jan 2018 06:55:41 -0500 Received: from mail-lf0-f53.google.com ([209.85.215.53]:35160 "EHLO mail-lf0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753559AbeAILzi (ORCPT ); Tue, 9 Jan 2018 06:55:38 -0500 X-Google-Smtp-Source: ACJfBotTfxntTdq4XO04xMXAJBW9MpKCKrUSE6BkWCLGoDIDhtqFVRWyb5UEeIkfOmSASZ6DoEQjAg== Date: Tue, 9 Jan 2018 12:55:35 +0100 From: Johan Hovold To: Mikhail Zaytsev Cc: Johan Hovold , Oliver Neukum , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Subject: Re: [PATCH v2 1/2] USB: serial: ark3116: Remove unused TIOCSSERIAL ioctl case. Message-ID: <20180109115535.GS11344@localhost> References: <20180106200809.41cdd723@debian> <20180106201402.03d2ac88@debian> <1515407612.29712.1.camel@suse.com> <20180108152858.GH11344@localhost> <20180109004507.0b7ac1a2@debian> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180109004507.0b7ac1a2@debian> User-Agent: Mutt/1.7.2 (2016-11-26) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: On Tue, Jan 09, 2018 at 12:45:30AM +0300, Mikhail Zaytsev wrote: > On Mon, 8 Jan 2018 16:28:58 +0100 Johan Hovold wrote: > > > On Mon, Jan 08, 2018 at 11:33:32AM +0100, Oliver Neukum wrote: > > > Am Samstag, den 06.01.2018, 20:14 +0300 schrieb Mikhail Zaytsev: > > > > The patch removes unused TIOCSSERIAL ioctl case and adds the default block > > > > to the switch. This will make the ioctl return -ENOTTY to user space (e.g. > > > > setserial), because TIOCSSERIAL really isn't supported for these devices > > > > currently. > > > > > > Hi, > > > > > > this will break software that is now running on these devices, > > > won't it? Do you know why those devices basically ignore the > > > ioctl? > > > > Yeah, that was my initial reactions as well, but then again, any sane > > user space cannot rely on these ioctl being implemented for all tty > > devices. > > > > I did some digging now and these (dummy) ioctl implementations where > > added by commit 2f430b4bbae7 ("USB: ark3116: Add TIOCGSERIAL and > > TIOCSSERIAL ioctl calls.") back in 2006. This in turn appears to have > > been triggered by a change in a user space tool, wvdial, which started > > erroring out if either was missing. > > > > I found a couple of bug reports about that through google, and looking > > at the wvstreams (library) code now, it looks like the issue has indeed > > been resolved by handling errors more gracefully (e.g. just logging > > them). > > > > So I'm willing to give this a try, and if anyone complains later we add > > back (or implement) TIOCSSERIAL. > > > > Thanks Johan. I looked the commit 2f430b4bbae7. Author just did a cut'n'paste > from other USB serial drivers. I think that it would be better remove > the TIOCGSERIAL implementation too. I've applied this one now after adding some of the backstory from above to the commit message. Thanks, Johan