From 078a10df24ac87d18c2d52fb501ff652f481fb5b Mon Sep 17 00:00:00 2001
From: Ian Abbott <abbotti@mev.co.uk>
Date: Mon, 21 Sep 2009 16:05:01 -0400
Subject: [PATCH] Staging: comedi: ni_65xx.c: fix output inversion problem.
When reading DO subdevice with inverted outputs invert the values read
back from the ports to match the inversion of values written.
Signed-off-by: Frank Mori Hess <fmhess@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
drivers/staging/comedi/drivers/ni_65xx.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/staging/comedi/drivers/ni_65xx.c b/drivers/staging/comedi/drivers/ni_65xx.c
index b664ce083fc5..bbf75eb6d7f2 100644
--- a/drivers/staging/comedi/drivers/ni_65xx.c
+++ b/drivers/staging/comedi/drivers/ni_65xx.c
@@ -457,6 +457,12 @@ static int ni_65xx_dio_insn_bits(struct comedi_device *dev,
port_read_bits =
readb(private(dev)->mite->daq_io_addr + Port_Data(port));
/* printk("read 0x%x from port %i\n", port_read_bits, port); */
+ if (s->type == COMEDI_SUBD_DO && board(dev)->invert_outputs) {
+ /* Outputs inverted, so invert value read back from
+ * DO subdevice. (Does not apply to boards with DIO
+ * subdevice.) */
+ port_read_bits ^= 0xFF;
+ }
if (bitshift > 0) {
port_read_bits <<= bitshift;
} else {
--
2.20.1