From 99555fc25a5f2a40f0d111a67b13bcd8e8d826b1 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Mon, 24 Aug 2015 10:13:54 -0700 Subject: [PATCH] staging: comedi: usbduxfast: chanlist check is Step 5 of (*do_cmdtest) The channel list should be checked in Step 5 of the (*do_cmdtest) not as part of the (*do_cmd). Factor the check out of usbduxfast_ai_cmd(). Tidy up the factored out code. The channel number 'i' will never be greater than NUMCHANNELS due to the subdevice setup and the checks done in the code. The up/down of the semaphore is also not needed because the (*do_cmdtest) never actually tries to access the hardware. Signed-off-by: H Hartley Sweeten Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/usbduxfast.c | 58 ++++++++++++--------- 1 file changed, 34 insertions(+), 24 deletions(-) diff --git a/drivers/staging/comedi/drivers/usbduxfast.c b/drivers/staging/comedi/drivers/usbduxfast.c index d90dc59982be..16b28faa2ec2 100644 --- a/drivers/staging/comedi/drivers/usbduxfast.c +++ b/drivers/staging/comedi/drivers/usbduxfast.c @@ -332,6 +332,31 @@ static int usbduxfast_submit_urb(struct comedi_device *dev) return 0; } +static int usbduxfast_ai_check_chanlist(struct comedi_device *dev, + struct comedi_subdevice *s, + struct comedi_cmd *cmd) +{ + unsigned int gain0 = CR_RANGE(cmd->chanlist[0]); + int i; + + for (i = 0; i < cmd->chanlist_len; ++i) { + unsigned int chan = CR_CHAN(cmd->chanlist[i]); + unsigned int gain = CR_RANGE(cmd->chanlist[i]); + + if (chan != i) { + dev_err(dev->class_dev, + "channels are not consecutive\n"); + return -EINVAL; + } + if (gain != gain0 && cmd->chanlist_len > 3) { + dev_err(dev->class_dev, + "gain must be the same for all channels\n"); + return -EINVAL; + } + } + return 0; +} + static int usbduxfast_ai_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_cmd *cmd) @@ -417,7 +442,13 @@ static int usbduxfast_ai_cmdtest(struct comedi_device *dev, if (err) return 3; - /* step 4: fix up any arguments */ + /* Step 4: fix up any arguments */ + + /* Step 5: check channel list if it exists */ + if (cmd->chanlist && cmd->chanlist_len > 0) + err |= usbduxfast_ai_check_chanlist(dev, s, cmd); + if (err) + return 5; return 0; } @@ -460,8 +491,8 @@ static int usbduxfast_ai_cmd(struct comedi_device *dev, { struct usbduxfast_private *devpriv = dev->private; struct comedi_cmd *cmd = &s->async->cmd; - unsigned int chan, gain, rngmask = 0xff; - int i, j, ret; + unsigned int rngmask = 0xff; + int j, ret; int result; long steps, steps_tmp; @@ -481,27 +512,6 @@ static int usbduxfast_ai_cmd(struct comedi_device *dev, */ devpriv->ignore = PACKETS_TO_IGNORE; - gain = CR_RANGE(cmd->chanlist[0]); - for (i = 0; i < cmd->chanlist_len; ++i) { - chan = CR_CHAN(cmd->chanlist[i]); - if (chan != i) { - dev_err(dev->class_dev, - "channels are not consecutive\n"); - up(&devpriv->sem); - return -EINVAL; - } - if ((gain != CR_RANGE(cmd->chanlist[i])) - && (cmd->chanlist_len > 3)) { - dev_err(dev->class_dev, - "gain must be the same for all channels\n"); - up(&devpriv->sem); - return -EINVAL; - } - if (i >= NUMCHANNELS) { - dev_err(dev->class_dev, "chanlist too long\n"); - break; - } - } steps = 0; if (cmd->convert_src == TRIG_TIMER) steps = (cmd->convert_arg * 30) / 1000; -- 2.34.1