staging: comedi: introduce, and use, comedi_spriv_free()

The comedi_subdevice 'private' variable is a void * that is available
for the subdevice to use in manner. It's common in comedi drivers for
the driver to allocate memory for a subdevice and store the pointer
to that memory in the 'private' variable. It's then the responsibility
of the driver to free that memory when the device is detached.

Due to how the attach/detach works in comedi, the drivers need to do
some sanity checking before they can free the allocated memory during
the detach.

Introduce a helper function, comedi_spriv_free(), to handle freeing
the private data allocated for a subdevice. This allows moving all the
sanity checks into the helper function and makes it safe to call
with any context. It also allows removing some of the boilerplate
code in the (*detach) functions.

Remove the subdev_8255_cleanup() export in the 8255 subdevice driver
as well as the addi_watchdog_cleanup() export in the addi_watchdog
driver and use the new helper instead.

The amplc_dio200_common driver uses a number of local helper functions
to free the private data for it's subdevices. Remove those as well and
use the new helper.

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>

30 files changed, 50 insertions, 154 deletions

diff --git a/drivers/staging/comedi/comedidev.h b/drivers/staging/comedi/comedidev.h
index 26c55569813f..ce509d02c214 100644
--- a/drivers/staging/comedi/comedidev.h
+++ b/drivers/staging/comedi/comedidev.h
@@ -348,6 +348,8 @@ void comedi_buf_memcpy_from(struct comedi_async *async, unsigned int offset,
 
 int comedi_alloc_subdevices(struct comedi_device *, int);
 
+void comedi_spriv_free(struct comedi_device *, int subdev_num);
+
 int __comedi_request_region(struct comedi_device *,
 			    unsigned long start, unsigned long len);
 int comedi_request_region(struct comedi_device *,
diff --git a/drivers/staging/comedi/drivers.c b/drivers/staging/comedi/drivers.c
index 8a19f22d4ab9..2a28f64dc74c 100644
--- a/drivers/staging/comedi/drivers.c
+++ b/drivers/staging/comedi/drivers.c
@@ -86,6 +86,18 @@ int comedi_alloc_subdevices(struct comedi_device *dev, int num_subdevices)
 }
 EXPORT_SYMBOL_GPL(comedi_alloc_subdevices);
 
+void comedi_spriv_free(struct comedi_device *dev, int subdev_num)
+{
+	struct comedi_subdevice *s;
+
+	if (dev->subdevices && subdev_num < dev->n_subdevices) {
+		s = &dev->subdevices[subdev_num];
+		kfree(s->private);
+		s->private = NULL;
+	}
+}
+EXPORT_SYMBOL_GPL(comedi_spriv_free);
+
 static void cleanup_device(struct comedi_device *dev)
 {
 	int i;
diff --git a/drivers/staging/comedi/drivers/8255.c b/drivers/staging/comedi/drivers/8255.c
index ec4dacff0255..1d48aa602ece 100644
--- a/drivers/staging/comedi/drivers/8255.c
+++ b/drivers/staging/comedi/drivers/8255.c
@@ -334,12 +334,6 @@ int subdev_8255_init_irq(struct comedi_device *dev, struct comedi_subdevice *s,
 }
 EXPORT_SYMBOL_GPL(subdev_8255_init_irq);
 
-void subdev_8255_cleanup(struct comedi_device *dev, struct comedi_subdevice *s)
-{
-	kfree(s->private);
-}
-EXPORT_SYMBOL_GPL(subdev_8255_cleanup);
-
 /*
 
    Start of the 8255 standalone device
@@ -397,7 +391,7 @@ static void dev_8255_detach(struct comedi_device *dev)
 			spriv = s->private;
 			release_region(spriv->iobase, _8255_SIZE);
 		}
-		subdev_8255_cleanup(dev, s);
+		comedi_spriv_free(dev, i);
 	}
 }
 
diff --git a/drivers/staging/comedi/drivers/8255.h b/drivers/staging/comedi/drivers/8255.h
index 1e589b4b8b73..0f6e7492b7db 100644
--- a/drivers/staging/comedi/drivers/8255.h
+++ b/drivers/staging/comedi/drivers/8255.h
@@ -32,7 +32,6 @@ int subdev_8255_init(struct comedi_device *dev, struct comedi_subdevice *s,
 int subdev_8255_init_irq(struct comedi_device *dev, struct comedi_subdevice *s,
 			 int (*io) (int, int, int, unsigned long),
 			 unsigned long iobase);
-void subdev_8255_cleanup(struct comedi_device *dev, struct comedi_subdevice *s);
 void subdev_8255_interrupt(struct comedi_device *dev,
 			   struct comedi_subdevice *s);
 
diff --git a/drivers/staging/comedi/drivers/8255_pci.c b/drivers/staging/comedi/drivers/8255_pci.c
index de54ad3a64e6..76dec96aeb2a 100644
--- a/drivers/staging/comedi/drivers/8255_pci.c
+++ b/drivers/staging/comedi/drivers/8255_pci.c
@@ -241,20 +241,12 @@ static int pci_8255_auto_attach(struct comedi_device *dev,
 
 static void pci_8255_detach(struct comedi_device *dev)
 {
-	const struct pci_8255_boardinfo *board = comedi_board(dev);
 	struct pci_8255_private *devpriv = dev->private;
-	struct comedi_subdevice *s;
 	int i;
 
-	if (!board || !devpriv)
-		return;
-	if (dev->subdevices) {
-		for (i = 0; i < board->n_8255; i++) {
-			s = &dev->subdevices[i];
-			subdev_8255_cleanup(dev, s);
-		}
-	}
-	if (devpriv->mmio_base)
+	for (i = 0; i < dev->n_subdevices; i++)
+		comedi_spriv_free(dev, i);
+	if (devpriv && devpriv->mmio_base)
 		iounmap(devpriv->mmio_base);
 	comedi_pci_disable(dev);
 }
diff --git a/drivers/staging/comedi/drivers/addi_apci_1516.c b/drivers/staging/comedi/drivers/addi_apci_1516.c
index e66ff4e05cdb..ed01c56630bb 100644
--- a/drivers/staging/comedi/drivers/addi_apci_1516.c
+++ b/drivers/staging/comedi/drivers/addi_apci_1516.c
@@ -203,8 +203,7 @@ static void apci1516_detach(struct comedi_device *dev)
 {
 	if (dev->iobase)
 		apci1516_reset(dev);
-	if (dev->subdevices)
-		addi_watchdog_cleanup(&dev->subdevices[2]);
+	comedi_spriv_free(dev, 2);
 	comedi_pci_disable(dev);
 }
 
diff --git a/drivers/staging/comedi/drivers/addi_apci_2032.c b/drivers/staging/comedi/drivers/addi_apci_2032.c
index e5fa20aa7f2d..b666637f61be 100644
--- a/drivers/staging/comedi/drivers/addi_apci_2032.c
+++ b/drivers/staging/comedi/drivers/addi_apci_2032.c
@@ -354,8 +354,7 @@ static void apci2032_detach(struct comedi_device *dev)
 		free_irq(dev->irq, dev);
 	if (dev->read_subdev)
 		kfree(dev->read_subdev->private);
-	if (dev->subdevices)
-		addi_watchdog_cleanup(&dev->subdevices[1]);
+	comedi_spriv_free(dev, 1);
 	comedi_pci_disable(dev);
 }
 
diff --git a/drivers/staging/comedi/drivers/addi_apci_2200.c b/drivers/staging/comedi/drivers/addi_apci_2200.c
index 8cad37ccf73e..1cdc08d79792 100644
--- a/drivers/staging/comedi/drivers/addi_apci_2200.c
+++ b/drivers/staging/comedi/drivers/addi_apci_2200.c
@@ -130,8 +130,7 @@ static void apci2200_detach(struct comedi_device *dev)
 {
 	if (dev->iobase)
 		apci2200_reset(dev);
-	if (dev->subdevices)
-		addi_watchdog_cleanup(&dev->subdevices[2]);
+	comedi_spriv_free(dev, 2);
 	comedi_pci_disable(dev);
 }
 
diff --git a/drivers/staging/comedi/drivers/addi_watchdog.c b/drivers/staging/comedi/drivers/addi_watchdog.c
index 375ab665e091..1666b5f510d3 100644
--- a/drivers/staging/comedi/drivers/addi_watchdog.c
+++ b/drivers/staging/comedi/drivers/addi_watchdog.c
@@ -150,12 +150,6 @@ int addi_watchdog_init(struct comedi_subdevice *s, unsigned long iobase)
 }
 EXPORT_SYMBOL_GPL(addi_watchdog_init);
 
-void addi_watchdog_cleanup(struct comedi_subdevice *s)
-{
-	kfree(s->private);
-}
-EXPORT_SYMBOL_GPL(addi_watchdog_cleanup);
-
 static int __init addi_watchdog_module_init(void)
 {
 	return 0;
diff --git a/drivers/staging/comedi/drivers/addi_watchdog.h b/drivers/staging/comedi/drivers/addi_watchdog.h
index f374a7bff44d..83b47befa4d1 100644
--- a/drivers/staging/comedi/drivers/addi_watchdog.h
+++ b/drivers/staging/comedi/drivers/addi_watchdog.h
@@ -5,6 +5,5 @@
 
 void addi_watchdog_reset(unsigned long iobase);
 int addi_watchdog_init(struct comedi_subdevice *, unsigned long iobase);
-void addi_watchdog_cleanup(struct comedi_subdevice *s);
 
 #endif
diff --git a/drivers/staging/comedi/drivers/adv_pci_dio.c b/drivers/staging/comedi/drivers/adv_pci_dio.c
index e98ddcc6ecfa..f70c67471c13 100644
--- a/drivers/staging/comedi/drivers/adv_pci_dio.c
+++ b/drivers/staging/comedi/drivers/adv_pci_dio.c
@@ -1180,13 +1180,11 @@ static void pci_dio_detach(struct comedi_device *dev)
 		if (devpriv->valid)
 			pci_dio_reset(dev);
 	}
-	if (dev->subdevices) {
-		for (i = 0; i < dev->n_subdevices; i++) {
-			s = &dev->subdevices[i];
-			if (s->type == COMEDI_SUBD_DIO)
-				subdev_8255_cleanup(dev, s);
-			s->private = NULL;
-		}
+	for (i = 0; i < dev->n_subdevices; i++) {
+		s = &dev->subdevices[i];
+		if (s->type == COMEDI_SUBD_DIO)
+			comedi_spriv_free(dev, i);
+		s->private = NULL; /* some private data is static */
 	}
 	comedi_pci_disable(dev);
 }
diff --git a/drivers/staging/comedi/drivers/aio_aio12_8.c b/drivers/staging/comedi/drivers/aio_aio12_8.c
index e37d4a8f9240..a3ca5c6b6a06 100644
--- a/drivers/staging/comedi/drivers/aio_aio12_8.c
+++ b/drivers/staging/comedi/drivers/aio_aio12_8.c
@@ -261,8 +261,7 @@ static int aio_aio12_8_attach(struct comedi_device *dev,
 
 static void aio_aio12_8_detach(struct comedi_device *dev)
 {
-	if (dev->subdevices)
-		subdev_8255_cleanup(dev, &dev->subdevices[2]);
+	comedi_spriv_free(dev, 2);
 	if (dev->iobase)
 		release_region(dev->iobase, 24);
 }
diff --git a/drivers/staging/comedi/drivers/amplc_dio200_common.c b/drivers/staging/comedi/drivers/amplc_dio200_common.c
index 04a798e9d015..3403e5ccfa93 100644
--- a/drivers/staging/comedi/drivers/amplc_dio200_common.c
+++ b/drivers/staging/comedi/drivers/amplc_dio200_common.c
@@ -595,17 +595,6 @@ dio200_subdev_intr_init(struct comedi_device *dev, struct comedi_subdevice *s,
 }
 
 /*
- * This function cleans up an 'INTERRUPT' subdevice.
- */
-static void
-dio200_subdev_intr_cleanup(struct comedi_device *dev,
-			   struct comedi_subdevice *s)
-{
-	struct dio200_subdev_intr *subpriv = s->private;
-	kfree(subpriv);
-}
-
-/*
  * Interrupt service routine.
  */
 static irqreturn_t dio200_interrupt(int irq, void *d)
@@ -938,17 +927,6 @@ dio200_subdev_8254_init(struct comedi_device *dev, struct comedi_subdevice *s,
 }
 
 /*
- * This function cleans up an '8254' counter subdevice.
- */
-static void
-dio200_subdev_8254_cleanup(struct comedi_device *dev,
-			   struct comedi_subdevice *s)
-{
-	struct dio200_subdev_intr *subpriv = s->private;
-	kfree(subpriv);
-}
-
-/*
  * This function sets I/O directions for an '8255' DIO subdevice.
  */
 static void dio200_subdev_8255_set_dir(struct comedi_device *dev,
@@ -1065,17 +1043,6 @@ static int dio200_subdev_8255_init(struct comedi_device *dev,
 }
 
 /*
- * This function cleans up an '8255' DIO subdevice.
- */
-static void dio200_subdev_8255_cleanup(struct comedi_device *dev,
-				       struct comedi_subdevice *s)
-{
-	struct dio200_subdev_8255 *subpriv = s->private;
-
-	kfree(subpriv);
-}
-
-/*
  * Handle 'insn_read' for a timer subdevice.
  */
 static int dio200_subdev_timer_read(struct comedi_device *dev,
@@ -1178,15 +1145,6 @@ static int dio200_subdev_timer_init(struct comedi_device *dev,
 	return 0;
 }
 
-/*
- * This function cleans up a timer subdevice.
- */
-static void dio200_subdev_timer_cleanup(struct comedi_device *dev,
-					struct comedi_subdevice *s)
-{
-	/* Nothing to do. */
-}
-
 void amplc_dio200_set_enhance(struct comedi_device *dev, unsigned char val)
 {
 	dio200_write8(dev, DIO200_ENHANCE, val);
@@ -1282,20 +1240,13 @@ void amplc_dio200_common_detach(struct comedi_device *dev)
 	if (dev->subdevices) {
 		layout = dio200_board_layout(thisboard);
 		for (n = 0; n < dev->n_subdevices; n++) {
-			struct comedi_subdevice *s = &dev->subdevices[n];
 			switch (layout->sdtype[n]) {
 			case sd_8254:
-				dio200_subdev_8254_cleanup(dev, s);
-				break;
 			case sd_8255:
-				dio200_subdev_8255_cleanup(dev, s);
-				break;
 			case sd_intr:
-				dio200_subdev_intr_cleanup(dev, s);
+				comedi_spriv_free(dev, n);
 				break;
 			case sd_timer:
-				dio200_subdev_timer_cleanup(dev, s);
-				break;
 			default:
 				break;
 			}
diff --git a/drivers/staging/comedi/drivers/amplc_pc236.c b/drivers/staging/comedi/drivers/amplc_pc236.c
index e789383ce49d..0f1a0f806cc6 100644
--- a/drivers/staging/comedi/drivers/amplc_pc236.c
+++ b/drivers/staging/comedi/drivers/amplc_pc236.c
@@ -545,8 +545,7 @@ static void pc236_detach(struct comedi_device *dev)
 		pc236_intr_disable(dev);
 	if (dev->irq)
 		free_irq(dev->irq, dev);
-	if (dev->subdevices)
-		subdev_8255_cleanup(dev, &dev->subdevices[0]);
+	comedi_spriv_free(dev, 0);
 	if (is_isa_board(thisboard)) {
 		if (dev->iobase)
 			release_region(dev->iobase, PC236_IO_SIZE);
diff --git a/drivers/staging/comedi/drivers/amplc_pci230.c b/drivers/staging/comedi/drivers/amplc_pci230.c
index b6e4af444ef5..49200fbd60b9 100644
--- a/drivers/staging/comedi/drivers/amplc_pci230.c
+++ b/drivers/staging/comedi/drivers/amplc_pci230.c
@@ -2832,11 +2832,9 @@ static int pci230_auto_attach(struct comedi_device *dev,
 
 static void pci230_detach(struct comedi_device *dev)
 {
-	const struct pci230_board *thisboard = comedi_board(dev);
 	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
 
-	if (dev->subdevices && thisboard->have_dio)
-		subdev_8255_cleanup(dev, &dev->subdevices[2]);
+	comedi_spriv_free(dev, 2);
 	if (dev->irq)
 		free_irq(dev->irq, dev);
 	comedi_pci_disable(dev);
diff --git a/drivers/staging/comedi/drivers/cb_pcidas.c b/drivers/staging/comedi/drivers/cb_pcidas.c
index cdbeb0833d0b..53dd298d2b54 100644
--- a/drivers/staging/comedi/drivers/cb_pcidas.c
+++ b/drivers/staging/comedi/drivers/cb_pcidas.c
@@ -1608,8 +1608,7 @@ static void cb_pcidas_detach(struct comedi_device *dev)
 	}
 	if (dev->irq)
 		free_irq(dev->irq, dev);
-	if (dev->subdevices)
-		subdev_8255_cleanup(dev, &dev->subdevices[2]);
+	comedi_spriv_free(dev, 2);
 	comedi_pci_disable(dev);
 }
 
diff --git a/drivers/staging/comedi/drivers/cb_pcidas64.c b/drivers/staging/comedi/drivers/cb_pcidas64.c
index cfcde124143d..c3e5495b4f06 100644
--- a/drivers/staging/comedi/drivers/cb_pcidas64.c
+++ b/drivers/staging/comedi/drivers/cb_pcidas64.c
@@ -4163,8 +4163,7 @@ static void detach(struct comedi_device *dev)
 					devpriv->ao_dma_desc_bus_addr);
 		}
 	}
-	if (dev->subdevices)
-		subdev_8255_cleanup(dev, &dev->subdevices[4]);
+	comedi_spriv_free(dev, 4);
 	comedi_pci_disable(dev);
 }
 
diff --git a/drivers/staging/comedi/drivers/cb_pcidda.c b/drivers/staging/comedi/drivers/cb_pcidda.c
index 2da6bd663aff..f9b459888b8b 100644
--- a/drivers/staging/comedi/drivers/cb_pcidda.c
+++ b/drivers/staging/comedi/drivers/cb_pcidda.c
@@ -399,10 +399,8 @@ static int cb_pcidda_auto_attach(struct comedi_device *dev,
 
 static void cb_pcidda_detach(struct comedi_device *dev)
 {
-	if (dev->subdevices) {
-		subdev_8255_cleanup(dev, &dev->subdevices[1]);
-		subdev_8255_cleanup(dev, &dev->subdevices[2]);
-	}
+	comedi_spriv_free(dev, 1);
+	comedi_spriv_free(dev, 2);
 	comedi_pci_disable(dev);
 }
 
diff --git a/drivers/staging/comedi/drivers/cb_pcimdda.c b/drivers/staging/comedi/drivers/cb_pcimdda.c
index f7d1136be652..88f03ae6f3e6 100644
--- a/drivers/staging/comedi/drivers/cb_pcimdda.c
+++ b/drivers/staging/comedi/drivers/cb_pcimdda.c
@@ -199,8 +199,7 @@ static int cb_pcimdda_auto_attach(struct comedi_device *dev,
 
 static void cb_pcimdda_detach(struct comedi_device *dev)
 {
-	if (dev->subdevices)
-		subdev_8255_cleanup(dev, &dev->subdevices[1]);
+	comedi_spriv_free(dev, 1);
 	comedi_pci_disable(dev);
 }
 
diff --git a/drivers/staging/comedi/drivers/daqboard2000.c b/drivers/staging/comedi/drivers/daqboard2000.c
index ed3d6e510818..c1f14f0b6c1a 100644
--- a/drivers/staging/comedi/drivers/daqboard2000.c
+++ b/drivers/staging/comedi/drivers/daqboard2000.c
@@ -766,8 +766,7 @@ static void daqboard2000_detach(struct comedi_device *dev)
 {
 	struct daqboard2000_private *devpriv = dev->private;
 
-	if (dev->subdevices)
-		subdev_8255_cleanup(dev, &dev->subdevices[2]);
+	comedi_spriv_free(dev, 2);
 	if (dev->irq)
 		free_irq(dev->irq, dev);
 	if (devpriv) {
diff --git a/drivers/staging/comedi/drivers/das08.c b/drivers/staging/comedi/drivers/das08.c
index 9823aa06787a..ba12c1d605fb 100644
--- a/drivers/staging/comedi/drivers/das08.c
+++ b/drivers/staging/comedi/drivers/das08.c
@@ -568,8 +568,7 @@ EXPORT_SYMBOL_GPL(das08_common_attach);
 
 void das08_common_detach(struct comedi_device *dev)
 {
-	if (dev->subdevices)
-		subdev_8255_cleanup(dev, &dev->subdevices[4]);
+	comedi_spriv_free(dev, 4);
 }
 EXPORT_SYMBOL_GPL(das08_common_detach);
 
diff --git a/drivers/staging/comedi/drivers/das16.c b/drivers/staging/comedi/drivers/das16.c
index 50902ccb5193..c2b5015448ae 100644
--- a/drivers/staging/comedi/drivers/das16.c
+++ b/drivers/staging/comedi/drivers/das16.c
@@ -1339,8 +1339,7 @@ static void das16_detach(struct comedi_device *dev)
 	struct das16_private_struct *devpriv = dev->private;
 
 	das16_reset(dev);
-	if (dev->subdevices)
-		subdev_8255_cleanup(dev, &dev->subdevices[4]);
+	comedi_spriv_free(dev, 4);
 	if (devpriv) {
 		int i;
 		for (i = 0; i < 2; i++) {
diff --git a/drivers/staging/comedi/drivers/das16m1.c b/drivers/staging/comedi/drivers/das16m1.c
index 77f213b4450b..91aba224beb9 100644
--- a/drivers/staging/comedi/drivers/das16m1.c
+++ b/drivers/staging/comedi/drivers/das16m1.c
@@ -669,8 +669,7 @@ static int das16m1_attach(struct comedi_device *dev,
 
 static void das16m1_detach(struct comedi_device *dev)
 {
-	if (dev->subdevices)
-		subdev_8255_cleanup(dev, &dev->subdevices[3]);
+	comedi_spriv_free(dev, 3);
 	if (dev->irq)
 		free_irq(dev->irq, dev);
 	if (dev->iobase) {
diff --git a/drivers/staging/comedi/drivers/ni_65xx.c b/drivers/staging/comedi/drivers/ni_65xx.c
index 013392cfe2a1..3f71f0f54d3c 100644
--- a/drivers/staging/comedi/drivers/ni_65xx.c
+++ b/drivers/staging/comedi/drivers/ni_65xx.c
@@ -730,6 +730,7 @@ static int ni_65xx_auto_attach(struct comedi_device *dev,
 static void ni_65xx_detach(struct comedi_device *dev)
 {
 	struct ni_65xx_private *devpriv = dev->private;
+	int i;
 
 	if (devpriv && devpriv->mite && devpriv->mite->daq_io_addr) {
 		writeb(0x00,
@@ -738,15 +739,9 @@ static void ni_65xx_detach(struct comedi_device *dev)
 	}
 	if (dev->irq)
 		free_irq(dev->irq, dev);
+	for (i = 0; i < dev->n_subdevices; ++i)
+		comedi_spriv_free(dev, i);
 	if (devpriv) {
-		struct comedi_subdevice *s;
-		unsigned i;
-
-		for (i = 0; i < dev->n_subdevices; ++i) {
-			s = &dev->subdevices[i];
-			kfree(s->private);
-			s->private = NULL;
-		}
 		if (devpriv->mite) {
 			mite_unsetup(devpriv->mite);
 			mite_free(devpriv->mite);
diff --git a/drivers/staging/comedi/drivers/ni_atmio16d.c b/drivers/staging/comedi/drivers/ni_atmio16d.c
index 4bfe6c8d0cce..4fb36cd833df 100644
--- a/drivers/staging/comedi/drivers/ni_atmio16d.c
+++ b/drivers/staging/comedi/drivers/ni_atmio16d.c
@@ -767,13 +767,7 @@ static int atmio16d_attach(struct comedi_device *dev,
 
 static void atmio16d_detach(struct comedi_device *dev)
 {
-	const struct atmio16_board_t *board = comedi_board(dev);
-	struct comedi_subdevice *s;
-
-	if (dev->subdevices && board->has_8255) {
-		s = &dev->subdevices[3];
-		subdev_8255_cleanup(dev, s);
-	}
+	comedi_spriv_free(dev, 3);
 	if (dev->irq)
 		free_irq(dev->irq, dev);
 	reset_atmio16d(dev);
diff --git a/drivers/staging/comedi/drivers/ni_daq_dio24.c b/drivers/staging/comedi/drivers/ni_daq_dio24.c
index c17ffe3cf5c4..9b7805fda932 100644
--- a/drivers/staging/comedi/drivers/ni_daq_dio24.c
+++ b/drivers/staging/comedi/drivers/ni_daq_dio24.c
@@ -73,8 +73,7 @@ static int dio24_auto_attach(struct comedi_device *dev,
 
 static void dio24_detach(struct comedi_device *dev)
 {
-	if (dev->subdevices)
-		subdev_8255_cleanup(dev, &dev->subdevices[0]);
+	comedi_spriv_free(dev, 0);
 	comedi_pcmcia_disable(dev);
 }
 
diff --git a/drivers/staging/comedi/drivers/ni_labpc.c b/drivers/staging/comedi/drivers/ni_labpc.c
index 19961424d1df..d48511f0cacd 100644
--- a/drivers/staging/comedi/drivers/ni_labpc.c
+++ b/drivers/staging/comedi/drivers/ni_labpc.c
@@ -1860,14 +1860,10 @@ void labpc_common_detach(struct comedi_device *dev)
 {
 	const struct labpc_boardinfo *board = comedi_board(dev);
 	struct labpc_private *devpriv = dev->private;
-	struct comedi_subdevice *s;
 
 	if (!board)
 		return;
-	if (dev->subdevices) {
-		s = &dev->subdevices[2];
-		subdev_8255_cleanup(dev, s);
-	}
+	comedi_spriv_free(dev, 2);
 #ifdef CONFIG_ISA_DMA_API
 	/* only free stuff if it has been allocated by _attach */
 	kfree(devpriv->dma_buffer);
diff --git a/drivers/staging/comedi/drivers/ni_mio_common.c b/drivers/staging/comedi/drivers/ni_mio_common.c
index 0f8d05c35391..a46d579016d9 100644
--- a/drivers/staging/comedi/drivers/ni_mio_common.c
+++ b/drivers/staging/comedi/drivers/ni_mio_common.c
@@ -4068,19 +4068,14 @@ static int ni_serial_sw_readwrite8(struct comedi_device *dev,
 
 static void mio_common_detach(struct comedi_device *dev)
 {
-	const struct ni_board_struct *board = comedi_board(dev);
 	struct ni_private *devpriv = dev->private;
-	struct comedi_subdevice *s;
 
 	if (devpriv) {
 		if (devpriv->counter_dev) {
 			ni_gpct_device_destroy(devpriv->counter_dev);
 		}
 	}
-	if (dev->subdevices && board->has_8255) {
-		s = &dev->subdevices[NI_8255_DIO_SUBDEV];
-		subdev_8255_cleanup(dev, s);
-	}
+	comedi_spriv_free(dev, NI_8255_DIO_SUBDEV);
 }
 
 static void init_ao_67xx(struct comedi_device *dev, struct comedi_subdevice *s)
diff --git a/drivers/staging/comedi/drivers/pcl724.c b/drivers/staging/comedi/drivers/pcl724.c
index 2821ead2772c..0f5a4821cf5f 100644
--- a/drivers/staging/comedi/drivers/pcl724.c
+++ b/drivers/staging/comedi/drivers/pcl724.c
@@ -170,13 +170,10 @@ static int pcl724_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 static void pcl724_detach(struct comedi_device *dev)
 {
 	const struct pcl724_board *board = comedi_board(dev);
-	struct comedi_subdevice *s;
 	int i;
 
-	for (i = 0; i < dev->n_subdevices; i++) {
-		s = &dev->subdevices[i];
-		subdev_8255_cleanup(dev, s);
-	}
+	for (i = 0; i < dev->n_subdevices; i++)
+		comedi_spriv_free(dev, i);
 #ifdef PCL724_IRQ
 	if (dev->irq)
 		free_irq(dev->irq, dev);
diff --git a/drivers/staging/comedi/drivers/pcm3724.c b/drivers/staging/comedi/drivers/pcm3724.c
index 7f9266cefc16..19742d1ba568 100644
--- a/drivers/staging/comedi/drivers/pcm3724.c
+++ b/drivers/staging/comedi/drivers/pcm3724.c
@@ -252,15 +252,10 @@ static int pcm3724_attach(struct comedi_device *dev,
 
 static void pcm3724_detach(struct comedi_device *dev)
 {
-	struct comedi_subdevice *s;
 	int i;
 
-	if (dev->subdevices) {
-		for (i = 0; i < dev->n_subdevices; i++) {
-			s = &dev->subdevices[i];
-			subdev_8255_cleanup(dev, s);
-		}
-	}
+	for (i = 0; i < dev->n_subdevices; i++)
+		comedi_spriv_free(dev, i);
 	if (dev->iobase)
 		release_region(dev->iobase, PCM3724_SIZE);
 }