From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kevin Hilman Subject: Re: serial port input corruption with 2.6.32? Date: Wed, 06 Jan 2010 16:25:09 -0800 Message-ID: <874omy92xm.fsf@deeprootsystems.com> References: <5e088bd90912231259k12dfafeckecbaaa1d29cec4ed@mail.gmail.com> <4551feaf0912231306gfebba89rf4e5b014c3a74fe7@mail.gmail.com> <5e088bd90912231322y3f507e4bvc453583946340cb8@mail.gmail.com> <87k4vuak71.fsf@deeprootsystems.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-pw0-f42.google.com ([209.85.160.42]:44431 "EHLO mail-pw0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932458Ab0AGAZM convert rfc822-to-8bit (ORCPT ); Wed, 6 Jan 2010 19:25:12 -0500 Received: by pwj9 with SMTP id 9so11604784pwj.21 for ; Wed, 06 Jan 2010 16:25:11 -0800 (PST) In-Reply-To: (Vikram Pandita's message of "Thu\, 7 Jan 2010 05\:10\:50 +0530") Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: "Pandita, Vikram" Cc: Steve Sakoman , Robert Nelson , "linux-omap@vger.kernel.org" "Pandita, Vikram" writes: >>Steve Sakoman writes: >> >>> On Wed, Dec 23, 2009 at 1:06 PM, Robert Nelson wrote: >>>> On Wed, Dec 23, 2009 at 2:59 PM, Steve Sakoman = wrote: >>>>> I'm seeing some strange behavior with my console serial port with= 2.6.32. >>>>> > >>This will also have obvious and serious PM implications for non >>serial-console devices connected to UARTs (IrDA, bluetooth, modems, >>etc.) > > OMAP uarts for BT etc use h/w flow control, which is another way of > waking up omap before sending any chars and hence don=E2=80=99t loose= data. Good point. However, I haven't personally tested (or heard) that it actually works as would be expected. Can you confirm working BT over a UART with idle/unclocking enabled? Kevin > Console uses no flow control as you know. > >> >>I've heard some ideas of muxing the UART into GPIO mode when idle and >>having a bitbanging to get the first char so it is not lost, but >>haven't seen any patches to do it. >> >>While it doesn't really solve your problem, I hope it at least helps >>understand the reason for it. > > You could write a book on uart pm :) > >> >>Kevin >> >> >>-- >>To unsubscribe from this list: send the line "unsubscribe linux-omap"= in >>the body of a message to majordomo@vger.kernel.org >>More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-omap" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html