From 2f69915c728c3be41e12dbbbdd4eeb8d3388d58c Mon Sep 17 00:00:00 2001
From: H Hartley Sweeten <hsweeten@visionengravers.com>
Date: Mon, 15 Apr 2013 16:41:57 -0700
Subject: [PATCH] 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>
---
 drivers/staging/comedi/comedidev.h            |  2 +
 drivers/staging/comedi/drivers.c              | 12 +++++
 drivers/staging/comedi/drivers/8255.c         |  8 +--
 drivers/staging/comedi/drivers/8255.h         |  1 -
 drivers/staging/comedi/drivers/8255_pci.c     | 14 ++---
 .../staging/comedi/drivers/addi_apci_1516.c   |  3 +-
 .../staging/comedi/drivers/addi_apci_2032.c   |  3 +-
 .../staging/comedi/drivers/addi_apci_2200.c   |  3 +-
 .../staging/comedi/drivers/addi_watchdog.c    |  6 ---
 .../staging/comedi/drivers/addi_watchdog.h    |  1 -
 drivers/staging/comedi/drivers/adv_pci_dio.c  | 12 ++---
 drivers/staging/comedi/drivers/aio_aio12_8.c  |  3 +-
 .../comedi/drivers/amplc_dio200_common.c      | 51 +------------------
 drivers/staging/comedi/drivers/amplc_pc236.c  |  3 +-
 drivers/staging/comedi/drivers/amplc_pci230.c |  4 +-
 drivers/staging/comedi/drivers/cb_pcidas.c    |  3 +-
 drivers/staging/comedi/drivers/cb_pcidas64.c  |  3 +-
 drivers/staging/comedi/drivers/cb_pcidda.c    |  6 +--
 drivers/staging/comedi/drivers/cb_pcimdda.c   |  3 +-
 drivers/staging/comedi/drivers/daqboard2000.c |  3 +-
 drivers/staging/comedi/drivers/das08.c        |  3 +-
 drivers/staging/comedi/drivers/das16.c        |  3 +-
 drivers/staging/comedi/drivers/das16m1.c      |  3 +-
 drivers/staging/comedi/drivers/ni_65xx.c      | 11 ++--
 drivers/staging/comedi/drivers/ni_atmio16d.c  |  8 +--
 drivers/staging/comedi/drivers/ni_daq_dio24.c |  3 +-
 drivers/staging/comedi/drivers/ni_labpc.c     |  6 +--
 .../staging/comedi/drivers/ni_mio_common.c    |  7 +--
 drivers/staging/comedi/drivers/pcl724.c       |  7 +--
 drivers/staging/comedi/drivers/pcm3724.c      |  9 +---
 30 files changed, 50 insertions(+), 154 deletions(-)

diff --git a/drivers/staging/comedi/comedidev.h b/drivers/staging/comedi/comedidev.h
index 26c55569813f3..ce509d02c2143 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 8a19f22d4ab90..2a28f64dc74c0 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 ec4dacff0255c..1d48aa602ecea 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 1e589b4b8b73c..0f6e7492b7db7 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 de54ad3a64e6f..76dec96aeb2ad 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 e66ff4e05cdb7..ed01c56630bb7 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 e5fa20aa7f2d1..b666637f61bee 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 8cad37ccf73e7..1cdc08d79792d 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 375ab665e091a..1666b5f510d32 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 f374a7bff44de..83b47befa4d17 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 e98ddcc6ecfa4..f70c67471c13a 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 e37d4a8f92401..a3ca5c6b6a066 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 04a798e9d0156..3403e5ccfa930 100644
--- a/drivers/staging/comedi/drivers/amplc_dio200_common.c
+++ b/drivers/staging/comedi/drivers/amplc_dio200_common.c
@@ -594,17 +594,6 @@ dio200_subdev_intr_init(struct comedi_device *dev, struct comedi_subdevice *s,
 	return 0;
 }
 
-/*
- * 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.
  */
@@ -937,17 +926,6 @@ dio200_subdev_8254_init(struct comedi_device *dev, struct comedi_subdevice *s,
 	return 0;
 }
 
-/*
- * 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.
  */
@@ -1064,17 +1042,6 @@ static int dio200_subdev_8255_init(struct comedi_device *dev,
 	return 0;
 }
 
-/*
- * 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.
  */
@@ -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 e789383ce49d6..0f1a0f806cc69 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 b6e4af444ef57..49200fbd60b99 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 cdbeb0833d0b8..53dd298d2b544 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 cfcde124143df..c3e5495b4f06a 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 2da6bd663affc..f9b459888b8b8 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 f7d1136be652e..88f03ae6f3e67 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 ed3d6e510818d..c1f14f0b6c1a3 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 9823aa06787a2..ba12c1d605fb9 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 50902ccb51937..c2b5015448ae3 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 77f213b4450b2..91aba224beb91 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 013392cfe2a1a..3f71f0f54d3ce 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 4bfe6c8d0cce5..4fb36cd833df1 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 c17ffe3cf5c41..9b7805fda9325 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 19961424d1df4..d48511f0cacd5 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 0f8d05c35391b..a46d579016d95 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 2821ead2772c4..0f5a4821cf5fa 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 7f9266cefc169..19742d1ba5684 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);
 }
-- 
2.30.2