From a0341e5deb05c18c67b786d138799b9a107cdfbf Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Fri, 14 Aug 2015 15:23:28 -0700 Subject: [PATCH] staging: comedi: usbdux: use common code path to check the cmd->scan_begin_arg There are currently separate code paths to check the scan_begin_arg based of the USB speed. Refactor the code to use a common code path and simplify the code. Signed-off-by: H Hartley Sweeten Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/usbdux.c | 40 ++++++++++--------------- 1 file changed, 15 insertions(+), 25 deletions(-) diff --git a/drivers/staging/comedi/drivers/usbdux.c b/drivers/staging/comedi/drivers/usbdux.c index 1ba6dd93dd36..be4c2db21cc8 100644 --- a/drivers/staging/comedi/drivers/usbdux.c +++ b/drivers/staging/comedi/drivers/usbdux.c @@ -517,8 +517,7 @@ static int usbdux_ai_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_cmd *cmd) { struct usbdux_private *this_usbduxsub = dev->private; - int err = 0, i; - unsigned int tmp_timer; + int err = 0; /* Step 1 : check if triggers are trivially valid */ @@ -549,6 +548,10 @@ static int usbdux_ai_cmdtest(struct comedi_device *dev, err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, 0); if (cmd->scan_begin_src == TRIG_TIMER) { + /* full speed does 1kHz scans every USB frame */ + unsigned int arg = 1000000; + unsigned int min_arg = arg; + if (this_usbduxsub->high_speed) { /* * In high speed mode microframes are possible. @@ -556,33 +559,20 @@ static int usbdux_ai_cmdtest(struct comedi_device *dev, * sample one channel. Thus, the more channels * are in the channel list the more time we need. */ - i = 1; + int i = 1; + /* find a power of 2 for the number of channels */ - while (i < (cmd->chanlist_len)) + while (i < cmd->chanlist_len) i = i * 2; - err |= comedi_check_trigger_arg_min(&cmd-> - scan_begin_arg, - 1000000 / 8 * i); - /* now calc the real sampling rate with all the - * rounding errors */ - tmp_timer = - ((unsigned int)(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); - /* - * calc the real sampling rate with the rounding errors - */ - tmp_timer = ((unsigned int)(cmd->scan_begin_arg / - 1000000)) * 1000000; + arg /= 8; + min_arg = arg * i; } - err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, - tmp_timer); + err |= comedi_check_trigger_arg_min(&cmd->scan_begin_arg, + min_arg); + /* calc the real sampling rate with the rounding errors */ + arg = (cmd->scan_begin_arg / arg) * arg; + err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, arg); } err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg, -- 2.34.1