From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sebastian Andrzej Siewior Subject: Re: [RFC] am33xx: create child nodes for the two musb controllers Date: Thu, 27 Jun 2013 13:44:34 +0200 Message-ID: <51CC25A2.3080808@linutronix.de> References: <20130626153325.GA24075@linutronix.de> <51CC20CF.2080103@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: Received: from www.linutronix.de ([62.245.132.108]:40413 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752377Ab3F0Log (ORCPT ); Thu, 27 Jun 2013 07:44:36 -0400 In-Reply-To: <51CC20CF.2080103@ti.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Benoit Cousson Cc: Felipe Balbi , linux-usb@vger.kernel.org, linux-omap@vger.kernel.org On 06/27/2013 01:23 PM, Benoit Cousson wrote: > Hi Sebastian, Hi Benoit, > BTW, why do have so many DMA compared to the previous version? I added them, the previous had none and is PIO only. I currently use three cells per dma channel (the posted example had two). In general I think I have to request 2 * 15 dma channels for the 15 TX and RX endpoints. So we end up with 30 channels per device (and we have two of them). The DMA engine has specific queues which depend on the USB endpoint that is used. Instead of hacking this information in some kind of platform data I decided to push this detail into device tree. > I don't know the HW in detail, but that looks indeed much better and > seems to reflect the partitioning with multiple instances accurately. > > If Felipe is OK with that partitioning, I'll take it. Okay, thanks. > > Thanks, > Benoit Sebastian