[PATCH 3/6] comedi vmk80xx: simplify rinsn output calculation

From: J. Ali Harlow
Date: Wed May 18 2011 - 14:37:29 EST


vmk80xx_di_rinsn() and vmk80xx_do_rinsn() extract the required channel
data by inconsistent and overly-complex algorithms. Simplify them both.

Signed-off-by: J. Ali Harlow <ali@xxxxxxxxxxxxxxx>
---
drivers/staging/comedi/drivers/vmk80xx.c | 6 ++----
1 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/comedi/drivers/vmk80xx.c b/drivers/staging/comedi/drivers/vmk80xx.c
index 01cfb76..c86c866 100644
--- a/drivers/staging/comedi/drivers/vmk80xx.c
+++ b/drivers/staging/comedi/drivers/vmk80xx.c
@@ -747,7 +747,7 @@ static int vmk80xx_di_rinsn(struct comedi_device *cdev,
else
inp = rx_buf[reg];

- data[n] = ((inp & (1 << chan)) > 0);
+ data[n] = (inp >> chan) & 1;
}

up(&dev->limit_sem);
@@ -812,7 +812,6 @@ static int vmk80xx_do_rinsn(struct comedi_device *cdev,
struct vmk80xx_usb *dev = cdev->private;
int chan;
int reg;
- int mask;
int n;

dbgvm("vmk80xx: %s\n", __func__);
@@ -825,7 +824,6 @@ static int vmk80xx_do_rinsn(struct comedi_device *cdev,
chan = CR_CHAN(insn->chanspec);

reg = VMK8061_DO_REG;
- mask = 1 << chan;

dev->usb_tx_buf[0] = VMK8061_CMD_RD_DO;

@@ -833,7 +831,7 @@ static int vmk80xx_do_rinsn(struct comedi_device *cdev,
if (vmk80xx_read_packet(dev))
break;

- data[n] = (dev->usb_rx_buf[reg] & mask) >> chan;
+ data[n] = (dev->usb_rx_buf[reg] >> chan) & 1;
}

up(&dev->limit_sem);
--
1.7.4.1

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