From: H Hartley Sweeten <hsweeten@visionengravers.com>
Date: Tue, 20 Jan 2015 21:53:25 +0000 (-0700)
Subject: staging: comedi: adv_pci1710: transfer all ai samples in one step
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d6c42d78c019ecef96ee09b20e55adf46fd430a2;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

staging: comedi: adv_pci1710: transfer all ai samples in one step

The two step process to transfer the ai samples in pci1710_handle_fifo() doesn't
make any sense. If the async buffer does not have enough room for the samples the
core will set the async event COMEDI_CB_OVERFLOW which will cause the async command
to cancel. Splitting the transfer doesn't add any value.

Transfer all the samples in one step to simplify the code.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/staging/comedi/drivers/adv_pci1710.c b/drivers/staging/comedi/drivers/adv_pci1710.c
index 0a50053e6bb3..76075dbf1110 100644
--- a/drivers/staging/comedi/drivers/adv_pci1710.c
+++ b/drivers/staging/comedi/drivers/adv_pci1710.c
@@ -720,7 +720,6 @@ static void pci1710_handle_fifo(struct comedi_device *dev,
 {
 	struct pci1710_private *devpriv = dev->private;
 	struct comedi_cmd *cmd = &s->async->cmd;
-	unsigned int nsamples;
 	unsigned int m;
 
 	m = inw(dev->iobase + PCI171x_STATUS);
@@ -736,18 +735,8 @@ static void pci1710_handle_fifo(struct comedi_device *dev,
 		return;
 	}
 
-	nsamples = devpriv->max_samples;
-	if (comedi_samples_to_bytes(s, nsamples) >= s->async->prealloc_bufsz) {
-		m = comedi_bytes_to_samples(s, s->async->prealloc_bufsz);
-		if (move_block_from_fifo(dev, s, m))
-			return;
-		nsamples -= m;
-	}
-
-	if (nsamples) {
-		if (move_block_from_fifo(dev, s, nsamples))
-			return;
-	}
+	if (move_block_from_fifo(dev, s, devpriv->max_samples))
+		return;
 
 	if (cmd->stop_src == TRIG_COUNT &&
 	    s->async->scans_done >= cmd->stop_arg) {