Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754864AbbGXRFe (ORCPT ); Fri, 24 Jul 2015 13:05:34 -0400 Received: from sidious.london.02.net ([82.132.130.152]:42061 "EHLO mail.o2.co.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753891AbbGXRFa (ORCPT ); Fri, 24 Jul 2015 13:05:30 -0400 Message-ID: <55B26ED2.1070909@berndporr.me.uk> Date: Fri, 24 Jul 2015 17:58:58 +0100 From: Bernd Porr User-Agent: Thunderbird 2.0.0.24 (X11/20100228) MIME-Version: 1.0 To: Ian Abbott CC: driverdev-devel@linuxdriverproject.org, Greg Kroah-Hartman , H Hartley Sweeten , linux-kernel@vger.kernel.org Subject: Re: [PATCH 4/6] staging: comedi: usbduxsigma: round down AI scan_begin_arg at step 4. References: <1437666422-25222-1-git-send-email-abbotti@mev.co.uk> <1437666422-25222-5-git-send-email-abbotti@mev.co.uk> In-Reply-To: <1437666422-25222-5-git-send-email-abbotti@mev.co.uk> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2517 Lines: 68 Reviewed-by: Bernd Porr Ian Abbott wrote: > The return value of the `cmdtest` handler for a subdevice checks the > prospective new command in various steps and returns the step number at > which any problem was detected, or 0 if no problem was detected. It is > allowed to modify the command in various ways at each step. Corrections > for out-of-range values are generally made at step 3, and minor > adjustments such as rounding are generally made at step 4. > > The `cmdtest` handler for the AI subdevice (`usbduxsigma_ai_cmdtest()`) > currently modifies `cmd->scan_begin_arg` to bring it into range and > round it down at step 3. Move the rounding down part to step 4 to > follow the usual Comedi convention. > > Signed-off-by: Ian Abbott > --- > drivers/staging/comedi/drivers/usbduxsigma.c | 13 ++++++++----- > 1 file changed, 8 insertions(+), 5 deletions(-) > > diff --git a/drivers/staging/comedi/drivers/usbduxsigma.c b/drivers/staging/comedi/drivers/usbduxsigma.c > index 65a0df4..4655048 100644 > --- a/drivers/staging/comedi/drivers/usbduxsigma.c > +++ b/drivers/staging/comedi/drivers/usbduxsigma.c > @@ -518,17 +518,12 @@ static int usbduxsigma_ai_cmdtest(struct comedi_device *dev, > */ > err |= comedi_check_trigger_arg_min(&cmd->scan_begin_arg, > (125000 * interval)); > - > - tmp = (cmd->scan_begin_arg / 125000) * 125000; > } else { > /* full speed */ > /* 1kHz scans every USB frame */ > err |= comedi_check_trigger_arg_min(&cmd->scan_begin_arg, > 1000000); > - > - tmp = (cmd->scan_begin_arg / 1000000) * 1000000; > } > - err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, tmp); > > err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg, > cmd->chanlist_len); > @@ -541,6 +536,14 @@ static int usbduxsigma_ai_cmdtest(struct comedi_device *dev, > if (err) > return 3; > > + /* Step 4: fix up any arguments */ > + > + tmp = rounddown(cmd->scan_begin_arg, high_speed ? 125000 : 1000000); > + err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, tmp); > + > + if (err) > + return 4; > + > return 0; > } > -- http://www.berndporr.me.uk http://www.linux-usb-daq.co.uk http://www.imdb.com/name/nm3293421/ +44 (0)7840 340069 -- 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/