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: [RFC] dt-bindings: usb: add non-removable device property From: Greg Kroah-Hartman Message-Id: <20190228151330.GA1360@kroah.com> Date: Thu, 28 Feb 2019 16:13:30 +0100 To: Mans Rullgard Cc: Rob Herring , Mark Rutland , linux-usb@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org List-ID: T24gVGh1LCBGZWIgMjgsIDIwMTkgYXQgMDI6MzM6NDRQTSArMDAwMCwgTWFucyBSdWxsZ2FyZCB3 cm90ZToKPiBBZGQgYSBib29sZWFuIHByb3BlcnR5IGluZGljYXRpbmcgdGhhdCBhIGRldmljZSBp cyBoYXJkd2lyZWQgdG8gdGhlCj4gdXBzdHJlYW0gcG9ydC4gIEFsdGhvdWdoIGh1YnMgY2FuIHBy b3ZpZGUgdGhpcyBpbmZvcm1hdGlvbiwgdGhleSBhcmUgbm90Cj4gYWx3YXlzIGNvbmZpZ3VyZWQg Y29ycmVjdGx5LiAgQW4gYWx0ZXJuYXRlIG1lYW5zIG9mIGluZGljYXRpbmcgdGhpcyBmb3IKPiBi dWlsdC1pbiBVU0IgZGV2aWNlcyBpcyB0aHVzIHVzZWZ1bC4KPiAKPiBTaWduZWQtb2ZmLWJ5OiBN YW5zIFJ1bGxnYXJkIDxtYW5zQG1hbnNyLmNvbT4KPiAtLS0KPiBJIGhhdmUgYSBzaXR1YXRpb24g d2hlcmUgdXNlcnNwYWNlIHdvdWxkIGxpa2UgdG8ga25vdyB3aGljaCBVU0IgZGV2aWNlcwo+IGFy ZSBidWlsdC1pbiwgYnV0IHRoZSBvbi1ib2FyZCBodWIgZG9lc24ndCBoYXZlIHRoZSByaWdodCBz ZXR0aW5nLgo+IEFsc28sIHRoZSBodWIgaXRzZWxmIGNhbid0IGJlIGluZGljYXRlZCBhcyBmaXhl ZCBpbiBhbnkgb3RoZXIgd2F5IHRoYXQKPiBJJ20gYXdhcmUgb2YuCgpUaGVuIHRoYXQncyBhIGZp cm13YXJlIGJ1ZywgcmlnaHQ/ICBXZSBoYXZlIGEgd2F5IGZvciBmaXJtd2FyZSB0byBleHBvcnQK dGhpcyB0byB0aGUgVVNCIGNvcmUsIHdoeSBub3QgdXNlIHRoYXQ/ICBZb3VyIG9uLWJvYXJkIGh1 YiBzaG91bGQgZ2V0IGEKZmlybXdhcmUgdXBkYXRlIHdpdGggdGhpcyBpbmZvcm1hdGlvbiwgbGV0 J3Mgbm90IHRyeSB0byBjcmVhdGUKeWV0LWFub3RoZXItd2F5IHRvIGRlZmluZSB0aGlzIHR5cGUg b2YgaW5mb3JtYXRpb24gcGxlYXNlLgoKPiBJbiBhIHdheSwgYWRkaW5nIHRoaXMgcHJvcGVydHkg c2VlbXMgYSBiaXQgc2lsbHkgc2luY2UgZHQgY2FuIG9ubHkKPiBzZW5zaWJseSBiZSB1c2VkIGZv ciBoYXJkd2lyZWQgZGV2aWNlcyBpbiB0aGUgZmlyc3QgcGxhY2UuICBUaHVzIHRoZQo+IG1lcmUg cHJlc2VuY2Ugb2YgYSBkdCBub2RlIGNvdWxkIGJlIHRha2VuIHRvIGluZGljYXRlIHRoZSBzYW1l IHRoaW5nLgo+IE9uIHRoZSBvdGhlciBoYW5kLCBpdCdzIGNvbmNlaXZhYmxlIHRoYXQgc29tZW9u ZSBtaWdodCBkeW5hbWljYWxseQo+IGdlbmVyYXRlIGEgZGV2aWNldHJlZSBiYXNlZCBvbiB3aGF0 IGhhcHBlbnMgdG8gYmUgY29ubmVjdGVkIG9uIGJvb3Qgb3IKPiBzb21ldGhpbmcuICBGb3IgdGhh dCByZWFzb24sIGFuZCBleHBsaWNpdCBwcm9wZXJ0eSBzZWVtcyBzYWZlci4KPiAtLS0KPiAgRG9j dW1lbnRhdGlvbi9kZXZpY2V0cmVlL2JpbmRpbmdzL3VzYi91c2ItZGV2aWNlLnR4dCB8IDggKysr KysrKysKPiAgMSBmaWxlIGNoYW5nZWQsIDggaW5zZXJ0aW9ucygrKQoKQ2FuIHlvdSBzaG93IHNv bWUgY29kZSBhY3R1YWxseSB1c2luZyB0aGlzPyAgQWdhaW4sIHRoaXMgc2hvdWxkICJqdXN0Cndv cmsiIGZvciBVU0IgdG9kYXkgdW5sZXNzIHlvdXIgcGxhdGZvcm0gaXMgcmVhbGx5IGJyb2tlbiAo YW5kIGlmIGl0IGlzLApnbyBjb21wbGFpbiB0byB0aGUgdmVuZG9yLi4uKQoKdGhhbmtzLAoKZ3Jl ZyBrLWgK From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Kroah-Hartman Subject: Re: [RFC][PATCH] dt-bindings: usb: add non-removable device property Date: Thu, 28 Feb 2019 16:13:30 +0100 Message-ID: <20190228151330.GA1360@kroah.com> References: <20190228143344.16312-1-mans@mansr.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20190228143344.16312-1-mans@mansr.com> Sender: linux-kernel-owner@vger.kernel.org To: Mans Rullgard Cc: Rob Herring , Mark Rutland , linux-usb@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: devicetree@vger.kernel.org On Thu, Feb 28, 2019 at 02:33:44PM +0000, Mans Rullgard wrote: > Add a boolean property indicating that a device is hardwired to the > upstream port. Although hubs can provide this information, they are not > always configured correctly. An alternate means of indicating this for > built-in USB devices is thus useful. > > Signed-off-by: Mans Rullgard > --- > I have a situation where userspace would like to know which USB devices > are built-in, but the on-board hub doesn't have the right setting. > Also, the hub itself can't be indicated as fixed in any other way that > I'm aware of. Then that's a firmware bug, right? We have a way for firmware to export this to the USB core, why not use that? Your on-board hub should get a firmware update with this information, let's not try to create yet-another-way to define this type of information please. > In a way, adding this property seems a bit silly since dt can only > sensibly be used for hardwired devices in the first place. Thus the > mere presence of a dt node could be taken to indicate the same thing. > On the other hand, it's conceivable that someone might dynamically > generate a devicetree based on what happens to be connected on boot or > something. For that reason, and explicit property seems safer. > --- > Documentation/devicetree/bindings/usb/usb-device.txt | 8 ++++++++ > 1 file changed, 8 insertions(+) Can you show some code actually using this? Again, this should "just work" for USB today unless your platform is really broken (and if it is, go complain to the vendor...) thanks, greg k-h