Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755120Ab2JPRLN (ORCPT ); Tue, 16 Oct 2012 13:11:13 -0400 Received: from mail-wg0-f44.google.com ([74.125.82.44]:56053 "EHLO mail-wg0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752165Ab2JPRLM (ORCPT ); Tue, 16 Oct 2012 13:11:12 -0400 MIME-Version: 1.0 In-Reply-To: <201210161538.29571.poeschel@lemonage.de> References: <20120925085559.GL28670@sortiz-mobl> <201210160851.33324.poeschel@lemonage.de> <201210161538.29571.poeschel@lemonage.de> Date: Tue, 16 Oct 2012 19:11:10 +0200 Message-ID: Subject: Re: [PATCH v2 2/4] gpio: add viperboard gpio driver From: Linus Walleij To: Lars Poeschel Cc: Lars Poeschel , sameo@linux.intel.com, linux-kernel@vger.kernel.org, jic23@cam.ac.uk, khali@linux-fr.org, ben-linux@fluff.org, w.sang@pengutronix.de, grant.likely@secretlab.ca Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1382 Lines: 37 On Tue, Oct 16, 2012 at 3:38 PM, Lars Poeschel wrote: > I had a look at regmap. This is interesting. But there is no regmap_bus > implementation for usb. Are you pointing me in this direction ? ;-) I was more thinking about whether it would be useful to use for this MFD hub. So that for this MFD and it's children, you would use regmap to: 1) Cache registers 2) Marshall the register read/writes across USB I don't think it would be applicable for USB, as reading & writing registers across USB is a pretty odd usecase. (IIRC using control transfers right?) > And it is not guaranteed, that this "address" and "value" > are at the same position for other usb adapters. And this is getting even > worse, if I think of reading values out of the viperboard... I was mainly thinking about the Viperboard MFD complex. > I would stay at the "cache" implementation I presented in the patch - this is > too special. You're special just like everybody else ;-) But to be honest I haven't seen another USB device like this. Which probably means that next week there will be dozens of them... Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/