staging: comedi: drivers: use comedi_dio_update_state() for simple cases

Use comedi_dio_update_state() to handle the boilerplate code to update
the subdevice s->state for simple cases where the hardware is updated
when any channel is modified.

Also, fix a bug in the amplc_pc263 and amplc_pci263 drivers where the
current state is not returned in data[1].

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>

40 files changed, 135 insertions, 308 deletions

diff --git a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci1564.c b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci1564.c
index e3cc429403c0..84668544f52d 100644
--- a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci1564.c
+++ b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci1564.c
@@ -260,18 +260,13 @@ static int apci1564_do_insn_bits(struct comedi_device *dev,
 				 unsigned int *data)
 {
 	struct addi_private *devpriv = dev->private;
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
 
 	s->state = inl(devpriv->i_IobaseAmcc + APCI1564_DIGITAL_OP +
 			APCI1564_DIGITAL_OP_RW);
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
 
+	if (comedi_dio_update_state(s, data))
 		outl(s->state, devpriv->i_IobaseAmcc + APCI1564_DIGITAL_OP +
 			APCI1564_DIGITAL_OP_RW);
-	}
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3200.c b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3200.c
index 32dce0329fd5..dc73d4d348ed 100644
--- a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3200.c
+++ b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3200.c
@@ -623,16 +623,11 @@ static int apci3200_do_insn_bits(struct comedi_device *dev,
 				 unsigned int *data)
 {
 	struct addi_private *devpriv = dev->private;
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
 
 	s->state = inl(devpriv->i_IobaseAddon) & 0xf;
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
 
+	if (comedi_dio_update_state(s, data))
 		outl(s->state, devpriv->i_IobaseAddon);
-	}
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/addi_apci_1516.c b/drivers/staging/comedi/drivers/addi_apci_1516.c
index 08674c18cf42..9d1b1425c60b 100644
--- a/drivers/staging/comedi/drivers/addi_apci_1516.c
+++ b/drivers/staging/comedi/drivers/addi_apci_1516.c
@@ -90,16 +90,10 @@ static int apci1516_do_insn_bits(struct comedi_device *dev,
 				 struct comedi_insn *insn,
 				 unsigned int *data)
 {
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
-
 	s->state = inw(dev->iobase + APCI1516_DO_REG);
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
 
+	if (comedi_dio_update_state(s, data))
 		outw(s->state, dev->iobase + APCI1516_DO_REG);
-	}
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/addi_apci_2032.c b/drivers/staging/comedi/drivers/addi_apci_2032.c
index 6b0ea16ff546..c77ee8732d38 100644
--- a/drivers/staging/comedi/drivers/addi_apci_2032.c
+++ b/drivers/staging/comedi/drivers/addi_apci_2032.c
@@ -57,16 +57,10 @@ static int apci2032_do_insn_bits(struct comedi_device *dev,
 				 struct comedi_insn *insn,
 				 unsigned int *data)
 {
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
-
 	s->state = inl(dev->iobase + APCI2032_DO_REG);
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
 
+	if (comedi_dio_update_state(s, data))
 		outl(s->state, dev->iobase + APCI2032_DO_REG);
-	}
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/addi_apci_2200.c b/drivers/staging/comedi/drivers/addi_apci_2200.c
index 92ac8ece8494..7fb32e778d8b 100644
--- a/drivers/staging/comedi/drivers/addi_apci_2200.c
+++ b/drivers/staging/comedi/drivers/addi_apci_2200.c
@@ -50,16 +50,10 @@ static int apci2200_do_insn_bits(struct comedi_device *dev,
 				 struct comedi_insn *insn,
 				 unsigned int *data)
 {
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
-
 	s->state = inw(dev->iobase + APCI2200_DO_REG);
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
 
+	if (comedi_dio_update_state(s, data))
 		outw(s->state, dev->iobase + APCI2200_DO_REG);
-	}
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/addi_apci_3501.c b/drivers/staging/comedi/drivers/addi_apci_3501.c
index d9650ffb7d2f..6138440b919e 100644
--- a/drivers/staging/comedi/drivers/addi_apci_3501.c
+++ b/drivers/staging/comedi/drivers/addi_apci_3501.c
@@ -161,16 +161,10 @@ static int apci3501_do_insn_bits(struct comedi_device *dev,
 				 struct comedi_insn *insn,
 				 unsigned int *data)
 {
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
-
 	s->state = inl(dev->iobase + APCI3501_DO_REG);
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
 
+	if (comedi_dio_update_state(s, data))
 		outl(s->state, dev->iobase + APCI3501_DO_REG);
-	}
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/addi_apci_3xxx.c b/drivers/staging/comedi/drivers/addi_apci_3xxx.c
index cf5dd10eaf91..fcec604bebf7 100644
--- a/drivers/staging/comedi/drivers/addi_apci_3xxx.c
+++ b/drivers/staging/comedi/drivers/addi_apci_3xxx.c
@@ -664,16 +664,10 @@ static int apci3xxx_do_insn_bits(struct comedi_device *dev,
 				 struct comedi_insn *insn,
 				 unsigned int *data)
 {
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
-
 	s->state = inl(dev->iobase + 48) & 0xf;
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
 
+	if (comedi_dio_update_state(s, data))
 		outl(s->state, dev->iobase + 48);
-	}
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/adl_pci6208.c b/drivers/staging/comedi/drivers/adl_pci6208.c
index 28975061134b..60f1f5c9532d 100644
--- a/drivers/staging/comedi/drivers/adl_pci6208.c
+++ b/drivers/staging/comedi/drivers/adl_pci6208.c
@@ -141,15 +141,8 @@ static int pci6208_do_insn_bits(struct comedi_device *dev,
 				struct comedi_insn *insn,
 				unsigned int *data)
 {
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
-
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
-
+	if (comedi_dio_update_state(s, data))
 		outw(s->state, dev->iobase + PCI6208_DIO);
-	}
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/adl_pci7x3x.c b/drivers/staging/comedi/drivers/adl_pci7x3x.c
index 81b7203f824f..5617f5ca384a 100644
--- a/drivers/staging/comedi/drivers/adl_pci7x3x.c
+++ b/drivers/staging/comedi/drivers/adl_pci7x3x.c
@@ -112,21 +112,10 @@ static int adl_pci7x3x_do_insn_bits(struct comedi_device *dev,
 				    unsigned int *data)
 {
 	unsigned long reg = (unsigned long)s->private;
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
-
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
 
+	if (comedi_dio_update_state(s, data))
 		outl(s->state, dev->iobase + reg);
-	}
 
-	/*
-	 * NOTE: The output register is not readable.
-	 * This returned state will not be correct until all the
-	 * outputs have been updated.
-	 */
 	data[1] = s->state;
 
 	return insn->n;
diff --git a/drivers/staging/comedi/drivers/adl_pci9111.c b/drivers/staging/comedi/drivers/adl_pci9111.c
index 78cea193504f..89ca5078e8b3 100644
--- a/drivers/staging/comedi/drivers/adl_pci9111.c
+++ b/drivers/staging/comedi/drivers/adl_pci9111.c
@@ -813,15 +813,8 @@ static int pci9111_do_insn_bits(struct comedi_device *dev,
 				struct comedi_insn *insn,
 				unsigned int *data)
 {
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
-
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
-
+	if (comedi_dio_update_state(s, data))
 		outw(s->state, dev->iobase + PCI9111_DIO_REG);
-	}
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/adl_pci9118.c b/drivers/staging/comedi/drivers/adl_pci9118.c
index 7d2cff3eab85..f50dbea67240 100644
--- a/drivers/staging/comedi/drivers/adl_pci9118.c
+++ b/drivers/staging/comedi/drivers/adl_pci9118.c
@@ -671,13 +671,12 @@ static int pci9118_insn_bits_di(struct comedi_device *dev,
 
 static int pci9118_insn_bits_do(struct comedi_device *dev,
 				struct comedi_subdevice *s,
-				struct comedi_insn *insn, unsigned int *data)
+				struct comedi_insn *insn,
+				unsigned int *data)
 {
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= (data[0] & data[1]);
+	if (comedi_dio_update_state(s, data))
 		outl(s->state & 0x0f, dev->iobase + PCI9118_DO);
-	}
+
 	data[1] = s->state;
 
 	return insn->n;
diff --git a/drivers/staging/comedi/drivers/adv_pci1710.c b/drivers/staging/comedi/drivers/adv_pci1710.c
index fe087253c870..3dacfaeca4cb 100644
--- a/drivers/staging/comedi/drivers/adv_pci1710.c
+++ b/drivers/staging/comedi/drivers/adv_pci1710.c
@@ -544,18 +544,14 @@ static int pci171x_insn_bits_di(struct comedi_device *dev,
 	return insn->n;
 }
 
-/*
-==============================================================================
-*/
 static int pci171x_insn_bits_do(struct comedi_device *dev,
 				struct comedi_subdevice *s,
-				struct comedi_insn *insn, unsigned int *data)
+				struct comedi_insn *insn,
+				unsigned int *data)
 {
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= (data[0] & data[1]);
+	if (comedi_dio_update_state(s, data))
 		outw(s->state, dev->iobase + PCI171x_DO);
-	}
+
 	data[1] = s->state;
 
 	return insn->n;
diff --git a/drivers/staging/comedi/drivers/adv_pci1723.c b/drivers/staging/comedi/drivers/adv_pci1723.c
index b793d6987b84..71321f75d0cd 100644
--- a/drivers/staging/comedi/drivers/adv_pci1723.c
+++ b/drivers/staging/comedi/drivers/adv_pci1723.c
@@ -205,19 +205,16 @@ static int pci1723_dio_insn_config(struct comedi_device *dev,
 	return insn->n;
 }
 
-/*
-  digital i/o bits read/write
-*/
 static int pci1723_dio_insn_bits(struct comedi_device *dev,
 				 struct comedi_subdevice *s,
-				 struct comedi_insn *insn, unsigned int *data)
+				 struct comedi_insn *insn,
+				 unsigned int *data)
 {
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= (data[0] & data[1]);
+	if (comedi_dio_update_state(s, data))
 		outw(s->state, dev->iobase + PCI1723_WRITE_DIGITAL_OUTPUT_CMD);
-	}
+
 	data[1] = inw(dev->iobase + PCI1723_READ_DIGITAL_INPUT_DATA);
+
 	return insn->n;
 }
 
diff --git a/drivers/staging/comedi/drivers/adv_pci_dio.c b/drivers/staging/comedi/drivers/adv_pci_dio.c
index f091fa0d304d..6bac665261f8 100644
--- a/drivers/staging/comedi/drivers/adv_pci_dio.c
+++ b/drivers/staging/comedi/drivers/adv_pci_dio.c
@@ -448,45 +448,39 @@ static int pci_dio_insn_bits_di_w(struct comedi_device *dev,
 	return insn->n;
 }
 
-/*
-==============================================================================
-*/
 static int pci_dio_insn_bits_do_b(struct comedi_device *dev,
 				  struct comedi_subdevice *s,
-				  struct comedi_insn *insn, unsigned int *data)
+				  struct comedi_insn *insn,
+				  unsigned int *data)
 {
 	const struct diosubd_data *d = (const struct diosubd_data *)s->private;
 	int i;
 
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= (data[0] & data[1]);
+	if (comedi_dio_update_state(s, data)) {
 		for (i = 0; i < d->regs; i++)
 			outb((s->state >> (8 * i)) & 0xff,
 			     dev->iobase + d->addr + i);
 	}
+
 	data[1] = s->state;
 
 	return insn->n;
 }
 
-/*
-==============================================================================
-*/
 static int pci_dio_insn_bits_do_w(struct comedi_device *dev,
 				  struct comedi_subdevice *s,
-				  struct comedi_insn *insn, unsigned int *data)
+				  struct comedi_insn *insn,
+				  unsigned int *data)
 {
 	const struct diosubd_data *d = (const struct diosubd_data *)s->private;
 	int i;
 
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= (data[0] & data[1]);
+	if (comedi_dio_update_state(s, data)) {
 		for (i = 0; i < d->regs; i++)
 			outw((s->state >> (16 * i)) & 0xffff,
 			     dev->iobase + d->addr + 2 * i);
 	}
+
 	data[1] = s->state;
 
 	return insn->n;
@@ -641,12 +635,10 @@ static int pci1760_insn_bits_di(struct comedi_device *dev,
 	return insn->n;
 }
 
-/*
-==============================================================================
-*/
 static int pci1760_insn_bits_do(struct comedi_device *dev,
 				struct comedi_subdevice *s,
-				struct comedi_insn *insn, unsigned int *data)
+				struct comedi_insn *insn,
+				unsigned int *data)
 {
 	int ret;
 	unsigned char omb[4] = {
@@ -657,14 +649,13 @@ static int pci1760_insn_bits_do(struct comedi_device *dev,
 	};
 	unsigned char imb[4];
 
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= (data[0] & data[1]);
+	if (comedi_dio_update_state(s, data)) {
 		omb[0] = s->state;
 		ret = pci1760_mbxrequest(dev, omb, imb);
 		if (!ret)
 			return ret;
 	}
+
 	data[1] = s->state;
 
 	return insn->n;
diff --git a/drivers/staging/comedi/drivers/aio_iiro_16.c b/drivers/staging/comedi/drivers/aio_iiro_16.c
index afe87cc89761..22b3dda135ff 100644
--- a/drivers/staging/comedi/drivers/aio_iiro_16.c
+++ b/drivers/staging/comedi/drivers/aio_iiro_16.c
@@ -45,9 +45,7 @@ static int aio_iiro_16_dio_insn_bits_write(struct comedi_device *dev,
 					   struct comedi_insn *insn,
 					   unsigned int *data)
 {
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= data[0] & data[1];
+	if (comedi_dio_update_state(s, data)) {
 		outb(s->state & 0xff, dev->iobase + AIO_IIRO_16_RELAY_0_7);
 		outb((s->state >> 8) & 0xff,
 		     dev->iobase + AIO_IIRO_16_RELAY_8_15);
diff --git a/drivers/staging/comedi/drivers/amplc_pc263.c b/drivers/staging/comedi/drivers/amplc_pc263.c
index e7108045f553..5b4b5ab34e2e 100644
--- a/drivers/staging/comedi/drivers/amplc_pc263.c
+++ b/drivers/staging/comedi/drivers/amplc_pc263.c
@@ -57,17 +57,16 @@ static const struct pc263_board pc263_boards[] = {
 
 static int pc263_do_insn_bits(struct comedi_device *dev,
 			      struct comedi_subdevice *s,
-			      struct comedi_insn *insn, unsigned int *data)
+			      struct comedi_insn *insn,
+			      unsigned int *data)
 {
-	/* The insn data is a mask in data[0] and the new data
-	 * in data[1], each channel cooresponding to a bit. */
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= data[0] & data[1];
-		/* Write out the new digital output lines */
-		outb(s->state & 0xFF, dev->iobase);
-		outb(s->state >> 8, dev->iobase + 1);
+	if (comedi_dio_update_state(s, data)) {
+		outb(s->state & 0xff, dev->iobase);
+		outb((s->state >> 8) & 0xff, dev->iobase + 1);
 	}
+
+	data[1] = s->state;
+
 	return insn->n;
 }
 
diff --git a/drivers/staging/comedi/drivers/amplc_pci263.c b/drivers/staging/comedi/drivers/amplc_pci263.c
index 145bb48f618e..4bd4ef8e88cd 100644
--- a/drivers/staging/comedi/drivers/amplc_pci263.c
+++ b/drivers/staging/comedi/drivers/amplc_pci263.c
@@ -44,17 +44,16 @@ The state of the outputs can be read.
 
 static int pci263_do_insn_bits(struct comedi_device *dev,
 			       struct comedi_subdevice *s,
-			       struct comedi_insn *insn, unsigned int *data)
+			       struct comedi_insn *insn,
+			       unsigned int *data)
 {
-	/* The insn data is a mask in data[0] and the new data
-	 * in data[1], each channel cooresponding to a bit. */
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= data[0] & data[1];
-		/* Write out the new digital output lines */
-		outb(s->state & 0xFF, dev->iobase);
-		outb(s->state >> 8, dev->iobase + 1);
+	if (comedi_dio_update_state(s, data)) {
+		outb(s->state & 0xff, dev->iobase);
+		outb((s->state >> 8) & 0xff, dev->iobase + 1);
 	}
+
+	data[1] = s->state;
+
 	return insn->n;
 }
 
diff --git a/drivers/staging/comedi/drivers/cb_das16_cs.c b/drivers/staging/comedi/drivers/cb_das16_cs.c
index 0ce93da70847..3e072955ea79 100644
--- a/drivers/staging/comedi/drivers/cb_das16_cs.c
+++ b/drivers/staging/comedi/drivers/cb_das16_cs.c
@@ -325,14 +325,11 @@ static int das16cs_ao_rinsn(struct comedi_device *dev,
 
 static int das16cs_dio_insn_bits(struct comedi_device *dev,
 				 struct comedi_subdevice *s,
-				 struct comedi_insn *insn, unsigned int *data)
+				 struct comedi_insn *insn,
+				 unsigned int *data)
 {
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= data[0] & data[1];
-
+	if (comedi_dio_update_state(s, data))
 		outw(s->state, dev->iobase + DAS16CS_DIO);
-	}
 
 	data[1] = inw(dev->iobase + DAS16CS_DIO);
 
diff --git a/drivers/staging/comedi/drivers/cb_pcidas64.c b/drivers/staging/comedi/drivers/cb_pcidas64.c
index 388dbd7a5d27..e49743aed65d 100644
--- a/drivers/staging/comedi/drivers/cb_pcidas64.c
+++ b/drivers/staging/comedi/drivers/cb_pcidas64.c
@@ -3490,18 +3490,15 @@ static int di_rbits(struct comedi_device *dev, struct comedi_subdevice *s,
 	return insn->n;
 }
 
-static int do_wbits(struct comedi_device *dev, struct comedi_subdevice *s,
-		    struct comedi_insn *insn, unsigned int *data)
+static int do_wbits(struct comedi_device *dev,
+		    struct comedi_subdevice *s,
+		    struct comedi_insn *insn,
+		    unsigned int *data)
 {
 	struct pcidas64_private *devpriv = dev->private;
 
-	data[0] &= 0xf;
-	/*  zero bits we are going to change */
-	s->state &= ~data[0];
-	/*  set new bits */
-	s->state |= data[0] & data[1];
-
-	writeb(s->state, devpriv->dio_counter_iobase + DO_REG);
+	if (comedi_dio_update_state(s, data))
+		writeb(s->state, devpriv->dio_counter_iobase + DO_REG);
 
 	data[1] = s->state;
 
@@ -3526,14 +3523,14 @@ static int dio_60xx_config_insn(struct comedi_device *dev,
 	return insn->n;
 }
 
-static int dio_60xx_wbits(struct comedi_device *dev, struct comedi_subdevice *s,
-			  struct comedi_insn *insn, unsigned int *data)
+static int dio_60xx_wbits(struct comedi_device *dev,
+			  struct comedi_subdevice *s,
+			  struct comedi_insn *insn,
+			  unsigned int *data)
 {
 	struct pcidas64_private *devpriv = dev->private;
 
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= (data[0] & data[1]);
+	if (comedi_dio_update_state(s, data)) {
 		writeb(s->state,
 		       devpriv->dio_counter_iobase + DIO_DATA_60XX_REG);
 	}
diff --git a/drivers/staging/comedi/drivers/contec_pci_dio.c b/drivers/staging/comedi/drivers/contec_pci_dio.c
index e781716bf355..89836c0828d9 100644
--- a/drivers/staging/comedi/drivers/contec_pci_dio.c
+++ b/drivers/staging/comedi/drivers/contec_pci_dio.c
@@ -40,17 +40,11 @@ Configuration Options: not applicable, uses comedi PCI auto config
 
 static int contec_do_insn_bits(struct comedi_device *dev,
 			       struct comedi_subdevice *s,
-			       struct comedi_insn *insn, unsigned int *data)
+			       struct comedi_insn *insn,
+			       unsigned int *data)
 {
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
-
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
-
+	if (comedi_dio_update_state(s, data))
 		outw(s->state, dev->iobase + PIO1616L_DO_REG);
-	}
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/das16.c b/drivers/staging/comedi/drivers/das16.c
index 1b0793f33b9f..fc058f8e8702 100644
--- a/drivers/staging/comedi/drivers/das16.c
+++ b/drivers/staging/comedi/drivers/das16.c
@@ -952,15 +952,8 @@ static int das16_do_insn_bits(struct comedi_device *dev,
 			      struct comedi_insn *insn,
 			      unsigned int *data)
 {
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
-
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
-
+	if (comedi_dio_update_state(s, data))
 		outb(s->state, dev->iobase + DAS16_DIO_REG);
-	}
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/das800.c b/drivers/staging/comedi/drivers/das800.c
index 11e16114e4e3..b80dd0362ffc 100644
--- a/drivers/staging/comedi/drivers/das800.c
+++ b/drivers/staging/comedi/drivers/das800.c
@@ -630,13 +630,9 @@ static int das800_do_insn_bits(struct comedi_device *dev,
 			       unsigned int *data)
 {
 	struct das800_private *devpriv = dev->private;
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
 	unsigned long irq_flags;
 
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
+	if (comedi_dio_update_state(s, data)) {
 		devpriv->do_bits = s->state << 4;
 
 		spin_lock_irqsave(&dev->spinlock, irq_flags);
diff --git a/drivers/staging/comedi/drivers/dt2801.c b/drivers/staging/comedi/drivers/dt2801.c
index 38918a1198aa..1a2b0e4b1ea5 100644
--- a/drivers/staging/comedi/drivers/dt2801.c
+++ b/drivers/staging/comedi/drivers/dt2801.c
@@ -528,23 +528,23 @@ static int dt2801_ao_insn_write(struct comedi_device *dev,
 
 static int dt2801_dio_insn_bits(struct comedi_device *dev,
 				struct comedi_subdevice *s,
-				struct comedi_insn *insn, unsigned int *data)
+				struct comedi_insn *insn,
+				unsigned int *data)
 {
-	int which = 0;
-
-	if (s == &dev->subdevices[3])
-		which = 1;
+	int which = (s == &dev->subdevices[3]) ? 1 : 0;
+	unsigned int val;
 
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= (data[0] & data[1]);
+	if (comedi_dio_update_state(s, data)) {
 		dt2801_writecmd(dev, DT_C_WRITE_DIG);
 		dt2801_writedata(dev, which);
 		dt2801_writedata(dev, s->state);
 	}
+
 	dt2801_writecmd(dev, DT_C_READ_DIG);
 	dt2801_writedata(dev, which);
-	dt2801_readdata(dev, data + 1);
+	dt2801_readdata(dev, &val);
+
+	data[1] = val;
 
 	return insn->n;
 }
diff --git a/drivers/staging/comedi/drivers/dt2811.c b/drivers/staging/comedi/drivers/dt2811.c
index a41a5716f358..0ca02fa7ba1b 100644
--- a/drivers/staging/comedi/drivers/dt2811.c
+++ b/drivers/staging/comedi/drivers/dt2811.c
@@ -353,11 +353,11 @@ static int dt2811_di_insn_bits(struct comedi_device *dev,
 
 static int dt2811_do_insn_bits(struct comedi_device *dev,
 			       struct comedi_subdevice *s,
-			       struct comedi_insn *insn, unsigned int *data)
+			       struct comedi_insn *insn,
+			       unsigned int *data)
 {
-	s->state &= ~data[0];
-	s->state |= data[0] & data[1];
-	outb(s->state, dev->iobase + DT2811_DIO);
+	if (comedi_dio_update_state(s, data))
+		outb(s->state, dev->iobase + DT2811_DIO);
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/dt282x.c b/drivers/staging/comedi/drivers/dt282x.c
index da3ee859bdbc..e89126a15e53 100644
--- a/drivers/staging/comedi/drivers/dt282x.c
+++ b/drivers/staging/comedi/drivers/dt282x.c
@@ -967,14 +967,12 @@ static int dt282x_ao_cancel(struct comedi_device *dev,
 
 static int dt282x_dio_insn_bits(struct comedi_device *dev,
 				struct comedi_subdevice *s,
-				struct comedi_insn *insn, unsigned int *data)
+				struct comedi_insn *insn,
+				unsigned int *data)
 {
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= (data[0] & data[1]);
-
+	if (comedi_dio_update_state(s, data))
 		outw(s->state, dev->iobase + DT2821_DIODAT);
-	}
+
 	data[1] = inw(dev->iobase + DT2821_DIODAT);
 
 	return insn->n;
diff --git a/drivers/staging/comedi/drivers/dt3000.c b/drivers/staging/comedi/drivers/dt3000.c
index 64ef87598b60..fec911fc8d68 100644
--- a/drivers/staging/comedi/drivers/dt3000.c
+++ b/drivers/staging/comedi/drivers/dt3000.c
@@ -665,13 +665,12 @@ static int dt3k_dio_insn_config(struct comedi_device *dev,
 
 static int dt3k_dio_insn_bits(struct comedi_device *dev,
 			      struct comedi_subdevice *s,
-			      struct comedi_insn *insn, unsigned int *data)
+			      struct comedi_insn *insn,
+			      unsigned int *data)
 {
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= data[1] & data[0];
+	if (comedi_dio_update_state(s, data))
 		dt3k_writesingle(dev, SUBS_DOUT, 0, s->state);
-	}
+
 	data[1] = dt3k_readsingle(dev, SUBS_DIN, 0, 0);
 
 	return insn->n;
diff --git a/drivers/staging/comedi/drivers/dt9812.c b/drivers/staging/comedi/drivers/dt9812.c
index b5e6f33dc217..64565d4c902d 100644
--- a/drivers/staging/comedi/drivers/dt9812.c
+++ b/drivers/staging/comedi/drivers/dt9812.c
@@ -580,15 +580,8 @@ static int dt9812_do_insn_bits(struct comedi_device *dev,
 			       struct comedi_insn *insn,
 			       unsigned int *data)
 {
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
-
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
-
+	if (comedi_dio_update_state(s, data))
 		dt9812_digital_out(dev, s->state);
-	}
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/dyna_pci10xx.c b/drivers/staging/comedi/drivers/dyna_pci10xx.c
index fd525f499f2a..f2a9f1c2f3b6 100644
--- a/drivers/staging/comedi/drivers/dyna_pci10xx.c
+++ b/drivers/staging/comedi/drivers/dyna_pci10xx.c
@@ -147,33 +147,23 @@ static int dyna_pci10xx_di_insn_bits(struct comedi_device *dev,
 	return insn->n;
 }
 
-/* digital output bit interface */
 static int dyna_pci10xx_do_insn_bits(struct comedi_device *dev,
-			      struct comedi_subdevice *s,
-			      struct comedi_insn *insn, unsigned int *data)
+				     struct comedi_subdevice *s,
+				     struct comedi_insn *insn,
+				     unsigned int *data)
 {
 	struct dyna_pci10xx_private *devpriv = dev->private;
 
-	/* The insn data is a mask in data[0] and the new data
-	 * in data[1], each channel cooresponding to a bit.
-	 * s->state contains the previous write data
-	 */
 	mutex_lock(&devpriv->mutex);
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= (data[0] & data[1]);
+	if (comedi_dio_update_state(s, data)) {
 		smp_mb();
 		outw_p(s->state, devpriv->BADR3);
 		udelay(10);
 	}
 
-	/*
-	 * On return, data[1] contains the value of the digital
-	 * input and output lines. We just return the software copy of the
-	 * output values if it was a purely digital output subdevice.
-	 */
 	data[1] = s->state;
 	mutex_unlock(&devpriv->mutex);
+
 	return insn->n;
 }
 
diff --git a/drivers/staging/comedi/drivers/icp_multi.c b/drivers/staging/comedi/drivers/icp_multi.c
index 17f9c0665469..15d87187b590 100644
--- a/drivers/staging/comedi/drivers/icp_multi.c
+++ b/drivers/staging/comedi/drivers/icp_multi.c
@@ -348,18 +348,13 @@ static int icp_multi_insn_bits_di(struct comedi_device *dev,
 
 static int icp_multi_insn_bits_do(struct comedi_device *dev,
 				  struct comedi_subdevice *s,
-				  struct comedi_insn *insn, unsigned int *data)
+				  struct comedi_insn *insn,
+				  unsigned int *data)
 {
 	struct icp_multi_private *devpriv = dev->private;
 
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= (data[0] & data[1]);
-
-		printk(KERN_DEBUG "Digital outputs = %4x \n", s->state);
-
+	if (comedi_dio_update_state(s, data))
 		writew(s->state, devpriv->io_addr + ICP_MULTI_DO);
-	}
 
 	data[1] = readw(devpriv->io_addr + ICP_MULTI_DI);
 
diff --git a/drivers/staging/comedi/drivers/multiq3.c b/drivers/staging/comedi/drivers/multiq3.c
index 9d75ea4e201b..3ca755eca285 100644
--- a/drivers/staging/comedi/drivers/multiq3.c
+++ b/drivers/staging/comedi/drivers/multiq3.c
@@ -163,11 +163,11 @@ static int multiq3_di_insn_bits(struct comedi_device *dev,
 
 static int multiq3_do_insn_bits(struct comedi_device *dev,
 				struct comedi_subdevice *s,
-				struct comedi_insn *insn, unsigned int *data)
+				struct comedi_insn *insn,
+				unsigned int *data)
 {
-	s->state &= ~data[0];
-	s->state |= (data[0] & data[1]);
-	outw(s->state, dev->iobase + MULTIQ3_DIGOUT_PORT);
+	if (comedi_dio_update_state(s, data))
+		outw(s->state, dev->iobase + MULTIQ3_DIGOUT_PORT);
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/ni_670x.c b/drivers/staging/comedi/drivers/ni_670x.c
index e2926ce3fb24..e4414cf110e7 100644
--- a/drivers/staging/comedi/drivers/ni_670x.c
+++ b/drivers/staging/comedi/drivers/ni_670x.c
@@ -136,20 +136,15 @@ static int ni_670x_ao_rinsn(struct comedi_device *dev,
 
 static int ni_670x_dio_insn_bits(struct comedi_device *dev,
 				 struct comedi_subdevice *s,
-				 struct comedi_insn *insn, unsigned int *data)
+				 struct comedi_insn *insn,
+				 unsigned int *data)
 {
 	struct ni_670x_private *devpriv = dev->private;
 	void __iomem *io_addr = devpriv->mite->daq_io_addr +
 					DIO_PORT0_DATA_OFFSET;
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
-
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
 
+	if (comedi_dio_update_state(s, data))
 		writel(s->state, io_addr);
-	}
 
 	data[1] = readl(io_addr);
 
diff --git a/drivers/staging/comedi/drivers/ni_at_ao.c b/drivers/staging/comedi/drivers/ni_at_ao.c
index b9122fd835e1..4e4b227e091f 100644
--- a/drivers/staging/comedi/drivers/ni_at_ao.c
+++ b/drivers/staging/comedi/drivers/ni_at_ao.c
@@ -233,13 +233,11 @@ static int atao_ao_rinsn(struct comedi_device *dev, struct comedi_subdevice *s,
 
 static int atao_dio_insn_bits(struct comedi_device *dev,
 			      struct comedi_subdevice *s,
-			      struct comedi_insn *insn, unsigned int *data)
+			      struct comedi_insn *insn,
+			      unsigned int *data)
 {
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= data[0] & data[1];
+	if (comedi_dio_update_state(s, data))
 		outw(s->state, dev->iobase + ATAO_DOUT);
-	}
 
 	data[1] = inw(dev->iobase + ATAO_DIN);
 
diff --git a/drivers/staging/comedi/drivers/ni_atmio16d.c b/drivers/staging/comedi/drivers/ni_atmio16d.c
index bb3491f5ad21..a9f7d40d6db2 100644
--- a/drivers/staging/comedi/drivers/ni_atmio16d.c
+++ b/drivers/staging/comedi/drivers/ni_atmio16d.c
@@ -558,13 +558,12 @@ static int atmio16d_ao_insn_write(struct comedi_device *dev,
 
 static int atmio16d_dio_insn_bits(struct comedi_device *dev,
 				  struct comedi_subdevice *s,
-				  struct comedi_insn *insn, unsigned int *data)
+				  struct comedi_insn *insn,
+				  unsigned int *data)
 {
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= (data[0] | data[1]);
+	if (comedi_dio_update_state(s, data))
 		outw(s->state, dev->iobase + MIO_16_DIG_OUT_REG);
-	}
+
 	data[1] = inw(dev->iobase + MIO_16_DIG_IN_REG);
 
 	return insn->n;
diff --git a/drivers/staging/comedi/drivers/ni_pcidio.c b/drivers/staging/comedi/drivers/ni_pcidio.c
index fad81bc97b6e..b6283a8a7cd4 100644
--- a/drivers/staging/comedi/drivers/ni_pcidio.c
+++ b/drivers/staging/comedi/drivers/ni_pcidio.c
@@ -657,15 +657,14 @@ static int ni_pcidio_insn_config(struct comedi_device *dev,
 
 static int ni_pcidio_insn_bits(struct comedi_device *dev,
 			       struct comedi_subdevice *s,
-			       struct comedi_insn *insn, unsigned int *data)
+			       struct comedi_insn *insn,
+			       unsigned int *data)
 {
 	struct nidio96_private *devpriv = dev->private;
 
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= (data[0] & data[1]);
+	if (comedi_dio_update_state(s, data))
 		writel(s->state, devpriv->mite->daq_io_addr + Port_IO(0));
-	}
+
 	data[1] = readl(devpriv->mite->daq_io_addr + Port_IO(0));
 
 	return insn->n;
diff --git a/drivers/staging/comedi/drivers/pcl812.c b/drivers/staging/comedi/drivers/pcl812.c
index 03a098900d34..2b10a95251bd 100644
--- a/drivers/staging/comedi/drivers/pcl812.c
+++ b/drivers/staging/comedi/drivers/pcl812.c
@@ -509,19 +509,16 @@ static int pcl812_di_insn_bits(struct comedi_device *dev,
 	return insn->n;
 }
 
-/*
-==============================================================================
-*/
 static int pcl812_do_insn_bits(struct comedi_device *dev,
 			       struct comedi_subdevice *s,
-			       struct comedi_insn *insn, unsigned int *data)
+			       struct comedi_insn *insn,
+			       unsigned int *data)
 {
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= data[0] & data[1];
+	if (comedi_dio_update_state(s, data)) {
 		outb(s->state & 0xff, dev->iobase + PCL812_DO_LO);
 		outb((s->state >> 8), dev->iobase + PCL812_DO_HI);
 	}
+
 	data[1] = s->state;
 
 	return insn->n;
diff --git a/drivers/staging/comedi/drivers/pcl818.c b/drivers/staging/comedi/drivers/pcl818.c
index a52ba82ff0e4..33cd4aae884e 100644
--- a/drivers/staging/comedi/drivers/pcl818.c
+++ b/drivers/staging/comedi/drivers/pcl818.c
@@ -418,21 +418,15 @@ static int pcl818_di_insn_bits(struct comedi_device *dev,
 	return insn->n;
 }
 
-/*
-==============================================================================
-   DIGITAL OUTPUT MODE0, 818 cards
-
-   only one sample per call is supported
-*/
 static int pcl818_do_insn_bits(struct comedi_device *dev,
 			       struct comedi_subdevice *s,
-			       struct comedi_insn *insn, unsigned int *data)
+			       struct comedi_insn *insn,
+			       unsigned int *data)
 {
-	s->state &= ~data[0];
-	s->state |= (data[0] & data[1]);
-
-	outb(s->state & 0xff, dev->iobase + PCL818_DO_LO);
-	outb((s->state >> 8), dev->iobase + PCL818_DO_HI);
+	if (comedi_dio_update_state(s, data)) {
+		outb(s->state & 0xff, dev->iobase + PCL818_DO_LO);
+		outb((s->state >> 8), dev->iobase + PCL818_DO_HI);
+	}
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/quatech_daqp_cs.c b/drivers/staging/comedi/drivers/quatech_daqp_cs.c
index 9775d3622a62..ece3031711eb 100644
--- a/drivers/staging/comedi/drivers/quatech_daqp_cs.c
+++ b/drivers/staging/comedi/drivers/quatech_daqp_cs.c
@@ -690,18 +690,12 @@ static int daqp_do_insn_bits(struct comedi_device *dev,
 			     unsigned int *data)
 {
 	struct daqp_private *devpriv = dev->private;
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
 
 	if (devpriv->stop)
 		return -EIO;
 
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
-
+	if (comedi_dio_update_state(s, data))
 		outb(s->state, dev->iobase + DAQP_DIGITAL_IO);
-	}
 
 	data[1] = s->state;
 
diff --git a/drivers/staging/comedi/drivers/rtd520.c b/drivers/staging/comedi/drivers/rtd520.c
index 93c980c62a23..3ec6632949bd 100644
--- a/drivers/staging/comedi/drivers/rtd520.c
+++ b/drivers/staging/comedi/drivers/rtd520.c
@@ -1217,15 +1217,9 @@ static int rtd_dio_insn_bits(struct comedi_device *dev,
 			     unsigned int *data)
 {
 	struct rtd_private *devpriv = dev->private;
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
-
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
 
+	if (comedi_dio_update_state(s, data))
 		writew(s->state & 0xff, devpriv->las0 + LAS0_DIO0);
-	}
 
 	data[1] = readw(devpriv->las0 + LAS0_DIO0) & 0xff;
 
diff --git a/drivers/staging/comedi/drivers/rti800.c b/drivers/staging/comedi/drivers/rti800.c
index cbb4ba5b852a..e1f3671ac056 100644
--- a/drivers/staging/comedi/drivers/rti800.c
+++ b/drivers/staging/comedi/drivers/rti800.c
@@ -267,13 +267,7 @@ static int rti800_do_insn_bits(struct comedi_device *dev,
 			       struct comedi_insn *insn,
 			       unsigned int *data)
 {
-	unsigned int mask = data[0];
-	unsigned int bits = data[1];
-
-	if (mask) {
-		s->state &= ~mask;
-		s->state |= (bits & mask);
-
+	if (comedi_dio_update_state(s, data)) {
 		/* Outputs are inverted... */
 		outb(s->state ^ 0xff, dev->iobase + RTI800_DO);
 	}
diff --git a/drivers/staging/comedi/drivers/s526.c b/drivers/staging/comedi/drivers/s526.c
index d629463b85a2..9950f59b1192 100644
--- a/drivers/staging/comedi/drivers/s526.c
+++ b/drivers/staging/comedi/drivers/s526.c
@@ -499,14 +499,11 @@ static int s526_ao_rinsn(struct comedi_device *dev, struct comedi_subdevice *s,
 
 static int s526_dio_insn_bits(struct comedi_device *dev,
 			      struct comedi_subdevice *s,
-			      struct comedi_insn *insn, unsigned int *data)
+			      struct comedi_insn *insn,
+			      unsigned int *data)
 {
-	if (data[0]) {
-		s->state &= ~data[0];
-		s->state |= data[0] & data[1];
-
+	if (comedi_dio_update_state(s, data))
 		outw(s->state, dev->iobase + REG_DIO);
-	}
 
 	data[1] = inw(dev->iobase + REG_DIO) & 0xff;