Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754047AbcD2PLT (ORCPT ); Fri, 29 Apr 2016 11:11:19 -0400 Received: from pygmy.kinoho.net ([134.0.27.24]:35782 "EHLO pygmy.kinoho.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752819AbcD2PLQ (ORCPT ); Fri, 29 Apr 2016 11:11:16 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Fri, 29 Apr 2016 17:11:13 +0200 From: Grigori Goronzy To: Johan Hovold Cc: Greg Kroah-Hartman , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Johan Hovold Subject: Re: [PATCH v4 01/13] USB: ch341: fix error handling on resume In-Reply-To: <20160429121601.GE22229@localhost> References: <1460754856-27908-1-git-send-email-greg@chown.ath.cx> <1460754856-27908-2-git-send-email-greg@chown.ath.cx> <20160429121601.GE22229@localhost> Message-ID: User-Agent: Roundcube Webmail/1.1.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1287 Lines: 39 On 2016-04-29 14:16, Johan Hovold wrote: > On Fri, Apr 15, 2016 at 11:14:04PM +0200, Grigori Goronzy wrote: >> This may fail, do not assume it always works. >> >> Signed-off-by: Grigori Goronzy >> --- >> drivers/usb/serial/ch341.c | 4 +--- >> 1 file changed, 1 insertion(+), 3 deletions(-) >> >> diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c >> index c73808f..63df8ce 100644 >> --- a/drivers/usb/serial/ch341.c >> +++ b/drivers/usb/serial/ch341.c >> @@ -544,9 +544,7 @@ static int ch341_reset_resume(struct usb_serial >> *serial) >> priv = usb_get_serial_port_data(serial->port[0]); >> >> /* reconfigure ch341 serial port after bus-reset */ >> - ch341_configure(serial->dev, priv); >> - >> - return 0; >> + return ch341_configure(serial->dev, priv); > > This is correct, but have noticed that resume is currently broken in > that the interrupt urb is never resubmitted on resume in case the port > is > already open? > > Also ch341_configure must not use GFP_KERNEL either if called from a > resume path (use GFP_NOIO). > > Care to fix this up as well? > Sure. How can I trigger a reset properly? AFAIR, I tried USBDEVFS_RESET and it didn't really do what I wanted, at least the reset_resume callback wasn't invoked. Grigori