From: Ian Abbott <abbotti@mev.co.uk>
Date: Thu, 23 Jul 2015 15:47:00 +0000 (+0100)
Subject: staging: comedi: usbduxsigma: round down AI scan_begin_arg at step 4.
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=333e40aee3f2d0457e2cbadc742619a6f449b2e7;p=linux.git
staging: comedi: usbduxsigma: round down AI scan_begin_arg at step 4.
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 <abbotti@mev.co.uk>
Reviewed-by: Bernd Porr <mail@berndporr.me.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
diff --git a/drivers/staging/comedi/drivers/usbduxsigma.c b/drivers/staging/comedi/drivers/usbduxsigma.c
index fdc880a4adaff..535cf01bca07d 100644
--- a/drivers/staging/comedi/drivers/usbduxsigma.c
+++ b/drivers/staging/comedi/drivers/usbduxsigma.c
@@ -519,17 +519,12 @@ 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);
@@ -542,6 +537,14 @@ 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;
}