diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c
index c561a0eda92a..423f882416d9 100644
--- a/drivers/staging/comedi/comedi_fops.c
+++ b/drivers/staging/comedi/comedi_fops.c
@@ -531,6 +531,21 @@ static bool comedi_is_subdevice_idle(struct comedi_subdevice *s)
 	return (runflags & (SRF_ERROR | SRF_RUNNING)) ? false : true;
 }
 
+/**
+ * comedi_set_spriv() - Set the subdevice private data pointer.
+ * @s: comedi_subdevice struct
+ * @data: pointer to the private data
+ *
+ * This also sets the subdevice runflags to allow the core to automatically
+ * free the private data during the detach.
+ */
+void comedi_set_spriv(struct comedi_subdevice *s, void *data)
+{
+	s->private = data;
+	comedi_set_subdevice_runflags(s, ~0, SRF_FREE_SPRIV);
+}
+EXPORT_SYMBOL_GPL(comedi_set_spriv);
+
 /*
    This function restores a subdevice to an idle state.
  */
diff --git a/drivers/staging/comedi/comedidev.h b/drivers/staging/comedi/comedidev.h
index 57deabf77418..e8dc7af8f5a1 100644
--- a/drivers/staging/comedi/comedidev.h
+++ b/drivers/staging/comedi/comedidev.h
@@ -265,10 +265,12 @@ enum subdevice_runflags {
 	/* indicates an COMEDI_CB_ERROR event has occurred since the last
 	 * command was started */
 	SRF_ERROR = 0x00000004,
-	SRF_RUNNING = 0x08000000
+	SRF_RUNNING = 0x08000000,
+	SRF_FREE_SPRIV = 0x80000000,	/* free s->private on detach */
 };
 
 bool comedi_is_subdevice_running(struct comedi_subdevice *s);
+void comedi_set_spriv(struct comedi_subdevice *s, void *data);
 
 int comedi_check_chanlist(struct comedi_subdevice *s,
 			  int n,
@@ -356,8 +358,6 @@ 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_load_firmware(struct comedi_device *, struct device *,
 			 const char *name,
 			 int (*cb)(struct comedi_device *,
diff --git a/drivers/staging/comedi/drivers.c b/drivers/staging/comedi/drivers.c
index f3e57fd8b2fb..e25eba5713c1 100644
--- a/drivers/staging/comedi/drivers.c
+++ b/drivers/staging/comedi/drivers.c
@@ -83,18 +83,6 @@ 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;
@@ -103,6 +91,8 @@ static void cleanup_device(struct comedi_device *dev)
 	if (dev->subdevices) {
 		for (i = 0; i < dev->n_subdevices; i++) {
 			s = &dev->subdevices[i];
+			if (s->runflags & SRF_FREE_SPRIV)
+				kfree(s->private);
 			comedi_free_subdevice_minor(s);
 			if (s->async) {
 				comedi_buf_alloc(dev, s, 0);
diff --git a/drivers/staging/comedi/drivers/8255.c b/drivers/staging/comedi/drivers/8255.c
index 1a1c2dae886b..dca9b40cefdc 100644
--- a/drivers/staging/comedi/drivers/8255.c
+++ b/drivers/staging/comedi/drivers/8255.c
@@ -288,12 +288,11 @@ int subdev_8255_init(struct comedi_device *dev, struct comedi_subdevice *s,
 	spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
 	if (!spriv)
 		return -ENOMEM;
+	comedi_set_spriv(s, spriv);
 
 	spriv->iobase	= iobase;
 	spriv->io	= io ? io : subdev_8255_io;
 
-	s->private	= spriv;
-
 	s->type		= COMEDI_SUBD_DIO;
 	s->subdev_flags	= SDF_READABLE | SDF_WRITABLE;
 	s->n_chan	= 24;
@@ -386,7 +385,6 @@ static void dev_8255_detach(struct comedi_device *dev)
 			spriv = s->private;
 			release_region(spriv->iobase, _8255_SIZE);
 		}
-		comedi_spriv_free(dev, i);
 	}
 }
 
diff --git a/drivers/staging/comedi/drivers/8255_pci.c b/drivers/staging/comedi/drivers/8255_pci.c
index 1117b61da3af..3d3547c19480 100644
--- a/drivers/staging/comedi/drivers/8255_pci.c
+++ b/drivers/staging/comedi/drivers/8255_pci.c
@@ -238,10 +238,7 @@ static int pci_8255_auto_attach(struct comedi_device *dev,
 static void pci_8255_detach(struct comedi_device *dev)
 {
 	struct pci_8255_private *devpriv = dev->private;
-	int i;
 
-	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 5bf6bb129cd4..b626738bb73c 100644
--- a/drivers/staging/comedi/drivers/addi_apci_1516.c
+++ b/drivers/staging/comedi/drivers/addi_apci_1516.c
@@ -196,7 +196,6 @@ static void apci1516_detach(struct comedi_device *dev)
 {
 	if (dev->iobase)
 		apci1516_reset(dev);
-	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 c0d83d8709f4..89ead8eb3c70 100644
--- a/drivers/staging/comedi/drivers/addi_apci_2032.c
+++ b/drivers/staging/comedi/drivers/addi_apci_2032.c
@@ -347,7 +347,6 @@ static void apci2032_detach(struct comedi_device *dev)
 		free_irq(dev->irq, dev);
 	if (dev->read_subdev)
 		kfree(dev->read_subdev->private);
-	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 060620e184d6..ca1bd92ecb17 100644
--- a/drivers/staging/comedi/drivers/addi_apci_2200.c
+++ b/drivers/staging/comedi/drivers/addi_apci_2200.c
@@ -123,7 +123,6 @@ static void apci2200_detach(struct comedi_device *dev)
 {
 	if (dev->iobase)
 		apci2200_reset(dev);
-	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 2c21a1625547..decc97d0e415 100644
--- a/drivers/staging/comedi/drivers/addi_watchdog.c
+++ b/drivers/staging/comedi/drivers/addi_watchdog.c
@@ -129,11 +129,10 @@ int addi_watchdog_init(struct comedi_subdevice *s, unsigned long iobase)
 	spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
 	if (!spriv)
 		return -ENOMEM;
+	comedi_set_spriv(s, spriv);
 
 	spriv->iobase = iobase;
 
-	s->private	= spriv;
-
 	s->type		= COMEDI_SUBD_TIMER;
 	s->subdev_flags	= SDF_WRITEABLE;
 	s->n_chan	= 1;
diff --git a/drivers/staging/comedi/drivers/adv_pci_dio.c b/drivers/staging/comedi/drivers/adv_pci_dio.c
index f70c67471c13..8e6ec75bd294 100644
--- a/drivers/staging/comedi/drivers/adv_pci_dio.c
+++ b/drivers/staging/comedi/drivers/adv_pci_dio.c
@@ -1173,19 +1173,11 @@ static int pci_dio_auto_attach(struct comedi_device *dev,
 static void pci_dio_detach(struct comedi_device *dev)
 {
 	struct pci_dio_private *devpriv = dev->private;
-	struct comedi_subdevice *s;
-	int i;
 
 	if (devpriv) {
 		if (devpriv->valid)
 			pci_dio_reset(dev);
 	}
-	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 77c92cb23d47..279dfe8951f7 100644
--- a/drivers/staging/comedi/drivers/aio_aio12_8.c
+++ b/drivers/staging/comedi/drivers/aio_aio12_8.c
@@ -255,17 +255,11 @@ static int aio_aio12_8_attach(struct comedi_device *dev,
 	return 0;
 }
 
-static void aio_aio12_8_detach(struct comedi_device *dev)
-{
-	comedi_spriv_free(dev, 2);
-	comedi_legacy_detach(dev);
-}
-
 static struct comedi_driver aio_aio12_8_driver = {
 	.driver_name	= "aio_aio12_8",
 	.module		= THIS_MODULE,
 	.attach		= aio_aio12_8_attach,
-	.detach		= aio_aio12_8_detach,
+	.detach		= comedi_legacy_detach,
 	.board_name	= &board_types[0].name,
 	.num_names	= ARRAY_SIZE(board_types),
 	.offset		= sizeof(struct aio12_8_boardtype),
diff --git a/drivers/staging/comedi/drivers/amplc_dio200_common.c b/drivers/staging/comedi/drivers/amplc_dio200_common.c
index 81d6ee4549cb..00c35a3541e8 100644
--- a/drivers/staging/comedi/drivers/amplc_dio200_common.c
+++ b/drivers/staging/comedi/drivers/amplc_dio200_common.c
@@ -559,6 +559,7 @@ dio200_subdev_intr_init(struct comedi_device *dev, struct comedi_subdevice *s,
 	subpriv = kzalloc(sizeof(*subpriv), GFP_KERNEL);
 	if (!subpriv)
 		return -ENOMEM;
+	comedi_set_spriv(s, subpriv);
 
 	subpriv->ofs = offset;
 	subpriv->valid_isns = valid_isns;
@@ -568,7 +569,6 @@ dio200_subdev_intr_init(struct comedi_device *dev, struct comedi_subdevice *s,
 		/* Disable interrupt sources. */
 		dio200_write8(dev, subpriv->ofs, 0);
 
-	s->private = subpriv;
 	s->type = COMEDI_SUBD_DI;
 	s->subdev_flags = SDF_READABLE | SDF_CMD_READ;
 	if (layout->has_int_sce) {
@@ -886,8 +886,8 @@ dio200_subdev_8254_init(struct comedi_device *dev, struct comedi_subdevice *s,
 	subpriv = kzalloc(sizeof(*subpriv), GFP_KERNEL);
 	if (!subpriv)
 		return -ENOMEM;
+	comedi_set_spriv(s, subpriv);
 
-	s->private = subpriv;
 	s->type = COMEDI_SUBD_COUNTER;
 	s->subdev_flags = SDF_WRITABLE | SDF_READABLE;
 	s->n_chan = 3;
@@ -1022,8 +1022,10 @@ static int dio200_subdev_8255_init(struct comedi_device *dev,
 	subpriv = kzalloc(sizeof(*subpriv), GFP_KERNEL);
 	if (!subpriv)
 		return -ENOMEM;
+	comedi_set_spriv(s, subpriv);
+
 	subpriv->ofs = offset;
-	s->private = subpriv;
+
 	s->type = COMEDI_SUBD_DIO;
 	s->subdev_flags = SDF_READABLE | SDF_WRITABLE;
 	s->n_chan = 24;
@@ -1225,28 +1227,11 @@ void amplc_dio200_common_detach(struct comedi_device *dev)
 {
 	const struct dio200_board *thisboard = comedi_board(dev);
 	struct dio200_private *devpriv = dev->private;
-	const struct dio200_layout *layout;
-	unsigned n;
 
 	if (!thisboard || !devpriv)
 		return;
 	if (dev->irq)
 		free_irq(dev->irq, dev);
-	if (dev->subdevices) {
-		layout = dio200_board_layout(thisboard);
-		for (n = 0; n < dev->n_subdevices; n++) {
-			switch (layout->sdtype[n]) {
-			case sd_8254:
-			case sd_8255:
-			case sd_intr:
-				comedi_spriv_free(dev, n);
-				break;
-			case sd_timer:
-			default:
-				break;
-			}
-		}
-	}
 }
 EXPORT_SYMBOL_GPL(amplc_dio200_common_detach);
 
diff --git a/drivers/staging/comedi/drivers/amplc_pc236.c b/drivers/staging/comedi/drivers/amplc_pc236.c
index 179d25e00ace..4e889b82cbf2 100644
--- a/drivers/staging/comedi/drivers/amplc_pc236.c
+++ b/drivers/staging/comedi/drivers/amplc_pc236.c
@@ -538,7 +538,6 @@ static void pc236_detach(struct comedi_device *dev)
 		return;
 	if (dev->iobase)
 		pc236_intr_disable(dev);
-	comedi_spriv_free(dev, 0);
 	if (is_isa_board(thisboard)) {
 		comedi_legacy_detach(dev);
 	} else if (is_pci_board(thisboard)) {
diff --git a/drivers/staging/comedi/drivers/amplc_pci230.c b/drivers/staging/comedi/drivers/amplc_pci230.c
index 08ff12837e00..846d6448fa4d 100644
--- a/drivers/staging/comedi/drivers/amplc_pci230.c
+++ b/drivers/staging/comedi/drivers/amplc_pci230.c
@@ -2830,7 +2830,6 @@ static void pci230_detach(struct comedi_device *dev)
 {
 	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
 
-	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 172f459b0af2..58bca184bf22 100644
--- a/drivers/staging/comedi/drivers/cb_pcidas.c
+++ b/drivers/staging/comedi/drivers/cb_pcidas.c
@@ -1602,7 +1602,6 @@ static void cb_pcidas_detach(struct comedi_device *dev)
 	}
 	if (dev->irq)
 		free_irq(dev->irq, dev);
-	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 11f8101d851a..43c0bf58771a 100644
--- a/drivers/staging/comedi/drivers/cb_pcidas64.c
+++ b/drivers/staging/comedi/drivers/cb_pcidas64.c
@@ -4158,7 +4158,6 @@ static void detach(struct comedi_device *dev)
 					devpriv->ao_dma_desc_bus_addr);
 		}
 	}
-	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 b74d4c38b5c3..2d3e920e5987 100644
--- a/drivers/staging/comedi/drivers/cb_pcidda.c
+++ b/drivers/staging/comedi/drivers/cb_pcidda.c
@@ -393,18 +393,11 @@ static int cb_pcidda_auto_attach(struct comedi_device *dev,
 	return 0;
 }
 
-static void cb_pcidda_detach(struct comedi_device *dev)
-{
-	comedi_spriv_free(dev, 1);
-	comedi_spriv_free(dev, 2);
-	comedi_pci_disable(dev);
-}
-
 static struct comedi_driver cb_pcidda_driver = {
 	.driver_name	= "cb_pcidda",
 	.module		= THIS_MODULE,
 	.auto_attach	= cb_pcidda_auto_attach,
-	.detach		= cb_pcidda_detach,
+	.detach		= comedi_pci_disable,
 };
 
 static int cb_pcidda_pci_probe(struct pci_dev *dev,
diff --git a/drivers/staging/comedi/drivers/cb_pcimdda.c b/drivers/staging/comedi/drivers/cb_pcimdda.c
index d3a796eef883..406cba8cba88 100644
--- a/drivers/staging/comedi/drivers/cb_pcimdda.c
+++ b/drivers/staging/comedi/drivers/cb_pcimdda.c
@@ -192,17 +192,11 @@ static int cb_pcimdda_auto_attach(struct comedi_device *dev,
 	return 1;
 }
 
-static void cb_pcimdda_detach(struct comedi_device *dev)
-{
-	comedi_spriv_free(dev, 1);
-	comedi_pci_disable(dev);
-}
-
 static struct comedi_driver cb_pcimdda_driver = {
 	.driver_name	= "cb_pcimdda",
 	.module		= THIS_MODULE,
 	.auto_attach	= cb_pcimdda_auto_attach,
-	.detach		= cb_pcimdda_detach,
+	.detach		= comedi_pci_disable,
 };
 
 static int cb_pcimdda_pci_probe(struct pci_dev *dev,
diff --git a/drivers/staging/comedi/drivers/daqboard2000.c b/drivers/staging/comedi/drivers/daqboard2000.c
index f5aa3860e3e7..44c912b48b6e 100644
--- a/drivers/staging/comedi/drivers/daqboard2000.c
+++ b/drivers/staging/comedi/drivers/daqboard2000.c
@@ -747,7 +747,6 @@ static void daqboard2000_detach(struct comedi_device *dev)
 {
 	struct daqboard2000_private *devpriv = dev->private;
 
-	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 64807eaa559e..2e7e3e202390 100644
--- a/drivers/staging/comedi/drivers/das08.c
+++ b/drivers/staging/comedi/drivers/das08.c
@@ -560,12 +560,6 @@ int das08_common_attach(struct comedi_device *dev, unsigned long iobase)
 }
 EXPORT_SYMBOL_GPL(das08_common_attach);
 
-void das08_common_detach(struct comedi_device *dev)
-{
-	comedi_spriv_free(dev, 4);
-}
-EXPORT_SYMBOL_GPL(das08_common_detach);
-
 static int __init das08_init(void)
 {
 	return 0;
diff --git a/drivers/staging/comedi/drivers/das08.h b/drivers/staging/comedi/drivers/das08.h
index c312870ab691..cce1b584200a 100644
--- a/drivers/staging/comedi/drivers/das08.h
+++ b/drivers/staging/comedi/drivers/das08.h
@@ -47,6 +47,5 @@ struct das08_private_struct {
 };
 
 int das08_common_attach(struct comedi_device *dev, unsigned long iobase);
-void das08_common_detach(struct comedi_device *dev);
 
 #endif /* _DAS08_H */
diff --git a/drivers/staging/comedi/drivers/das08_cs.c b/drivers/staging/comedi/drivers/das08_cs.c
index 3625b3eafe7c..885fb179c9b4 100644
--- a/drivers/staging/comedi/drivers/das08_cs.c
+++ b/drivers/staging/comedi/drivers/das08_cs.c
@@ -86,17 +86,11 @@ static int das08_cs_auto_attach(struct comedi_device *dev,
 	return das08_common_attach(dev, iobase);
 }
 
-static void das08_cs_detach(struct comedi_device *dev)
-{
-	das08_common_detach(dev);
-	comedi_pcmcia_disable(dev);
-}
-
 static struct comedi_driver driver_das08_cs = {
 	.driver_name	= "das08_cs",
 	.module		= THIS_MODULE,
 	.auto_attach	= das08_cs_auto_attach,
-	.detach		= das08_cs_detach,
+	.detach		= comedi_pcmcia_disable,
 };
 
 static int das08_pcmcia_attach(struct pcmcia_device *link)
diff --git a/drivers/staging/comedi/drivers/das08_isa.c b/drivers/staging/comedi/drivers/das08_isa.c
index 10e96e94515c..21a94389b8b2 100644
--- a/drivers/staging/comedi/drivers/das08_isa.c
+++ b/drivers/staging/comedi/drivers/das08_isa.c
@@ -189,17 +189,11 @@ static int das08_isa_attach(struct comedi_device *dev,
 	return das08_common_attach(dev, dev->iobase);
 }
 
-static void das08_isa_detach(struct comedi_device *dev)
-{
-	das08_common_detach(dev);
-	comedi_legacy_detach(dev);
-}
-
 static struct comedi_driver das08_isa_driver = {
 	.driver_name	= "isa-das08",
 	.module		= THIS_MODULE,
 	.attach		= das08_isa_attach,
-	.detach		= das08_isa_detach,
+	.detach		= comedi_legacy_detach,
 	.board_name	= &das08_isa_boards[0].name,
 	.num_names	= ARRAY_SIZE(das08_isa_boards),
 	.offset		= sizeof(das08_isa_boards[0]),
diff --git a/drivers/staging/comedi/drivers/das08_pci.c b/drivers/staging/comedi/drivers/das08_pci.c
index 351fbc6027f1..9c5d234e063f 100644
--- a/drivers/staging/comedi/drivers/das08_pci.c
+++ b/drivers/staging/comedi/drivers/das08_pci.c
@@ -75,17 +75,11 @@ static int das08_pci_auto_attach(struct comedi_device *dev,
 	return das08_common_attach(dev, dev->iobase);
 }
 
-static void das08_pci_detach(struct comedi_device *dev)
-{
-	das08_common_detach(dev);
-	comedi_pci_disable(dev);
-}
-
 static struct comedi_driver das08_pci_comedi_driver = {
 	.driver_name	= "pci-das08",
 	.module		= THIS_MODULE,
 	.auto_attach	= das08_pci_auto_attach,
-	.detach		= das08_pci_detach,
+	.detach		= comedi_pci_disable,
 };
 
 static int das08_pci_probe(struct pci_dev *dev,
diff --git a/drivers/staging/comedi/drivers/das16.c b/drivers/staging/comedi/drivers/das16.c
index dab7647ec2f5..dbec3ba99548 100644
--- a/drivers/staging/comedi/drivers/das16.c
+++ b/drivers/staging/comedi/drivers/das16.c
@@ -1333,7 +1333,6 @@ static void das16_detach(struct comedi_device *dev)
 	struct das16_private_struct *devpriv = dev->private;
 
 	das16_reset(dev);
-	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 e7ae2ffe8c79..0b33808c3a7d 100644
--- a/drivers/staging/comedi/drivers/das16m1.c
+++ b/drivers/staging/comedi/drivers/das16m1.c
@@ -666,7 +666,6 @@ static void das16m1_detach(struct comedi_device *dev)
 {
 	struct das16m1_private_struct *devpriv = dev->private;
 
-	comedi_spriv_free(dev, 3);
 	if (devpriv && devpriv->extra_iobase)
 		release_region(devpriv->extra_iobase, DAS16M1_SIZE2);
 	comedi_legacy_detach(dev);
diff --git a/drivers/staging/comedi/drivers/ni_65xx.c b/drivers/staging/comedi/drivers/ni_65xx.c
index 6a89e5c166e3..5907fd262a38 100644
--- a/drivers/staging/comedi/drivers/ni_65xx.c
+++ b/drivers/staging/comedi/drivers/ni_65xx.c
@@ -281,13 +281,16 @@ static inline struct ni_65xx_subdevice_private *sprivate(struct comedi_subdevice
 	return subdev->private;
 }
 
-static struct ni_65xx_subdevice_private *ni_65xx_alloc_subdevice_private(void)
+static int ni_65xx_alloc_subdevice_private(struct comedi_subdevice *s)
 {
-	struct ni_65xx_subdevice_private *subdev_private =
-	    kzalloc(sizeof(struct ni_65xx_subdevice_private), GFP_KERNEL);
-	if (subdev_private == NULL)
-		return NULL;
-	return subdev_private;
+	struct ni_65xx_subdevice_private *spriv;
+
+	spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
+	if (!spriv)
+		return -ENOMEM;
+	comedi_set_spriv(s, spriv);
+
+	return 0;
 }
 
 static int ni_65xx_config_filter(struct comedi_device *dev,
@@ -632,9 +635,9 @@ static int ni_65xx_auto_attach(struct comedi_device *dev,
 		s->maxdata = 1;
 		s->insn_config = ni_65xx_dio_insn_config;
 		s->insn_bits = ni_65xx_dio_insn_bits;
-		s->private = ni_65xx_alloc_subdevice_private();
-		if (s->private == NULL)
-			return -ENOMEM;
+		ret = ni_65xx_alloc_subdevice_private(s);
+		if (ret)
+			return ret;
 		sprivate(s)->base_port = 0;
 	} else {
 		s->type = COMEDI_SUBD_UNUSED;
@@ -649,9 +652,9 @@ static int ni_65xx_auto_attach(struct comedi_device *dev,
 		s->range_table = &range_digital;
 		s->maxdata = 1;
 		s->insn_bits = ni_65xx_dio_insn_bits;
-		s->private = ni_65xx_alloc_subdevice_private();
-		if (s->private == NULL)
-			return -ENOMEM;
+		ret = ni_65xx_alloc_subdevice_private(s);
+		if (ret)
+			return ret;
 		sprivate(s)->base_port = board->num_di_ports;
 	} else {
 		s->type = COMEDI_SUBD_UNUSED;
@@ -667,9 +670,9 @@ static int ni_65xx_auto_attach(struct comedi_device *dev,
 		s->maxdata = 1;
 		s->insn_config = ni_65xx_dio_insn_config;
 		s->insn_bits = ni_65xx_dio_insn_bits;
-		s->private = ni_65xx_alloc_subdevice_private();
-		if (s->private == NULL)
-			return -ENOMEM;
+		ret = ni_65xx_alloc_subdevice_private(s);
+		if (ret)
+			return ret;
 		sprivate(s)->base_port = 0;
 		for (i = 0; i < board->num_dio_ports; ++i) {
 			/*  configure all ports for input */
@@ -725,7 +728,6 @@ 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,
@@ -734,8 +736,6 @@ 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) {
 		if (devpriv->mite) {
 			mite_unsetup(devpriv->mite);
diff --git a/drivers/staging/comedi/drivers/ni_atmio16d.c b/drivers/staging/comedi/drivers/ni_atmio16d.c
index d280332d32d1..da7396f94297 100644
--- a/drivers/staging/comedi/drivers/ni_atmio16d.c
+++ b/drivers/staging/comedi/drivers/ni_atmio16d.c
@@ -762,7 +762,6 @@ static int atmio16d_attach(struct comedi_device *dev,
 
 static void atmio16d_detach(struct comedi_device *dev)
 {
-	comedi_spriv_free(dev, 3);
 	reset_atmio16d(dev);
 	comedi_legacy_detach(dev);
 }
diff --git a/drivers/staging/comedi/drivers/ni_daq_dio24.c b/drivers/staging/comedi/drivers/ni_daq_dio24.c
index 6ff1526bd063..d3d4eb9356a7 100644
--- a/drivers/staging/comedi/drivers/ni_daq_dio24.c
+++ b/drivers/staging/comedi/drivers/ni_daq_dio24.c
@@ -65,17 +65,11 @@ static int dio24_auto_attach(struct comedi_device *dev,
 	return 0;
 }
 
-static void dio24_detach(struct comedi_device *dev)
-{
-	comedi_spriv_free(dev, 0);
-	comedi_pcmcia_disable(dev);
-}
-
 static struct comedi_driver driver_dio24 = {
 	.driver_name	= "ni_daq_dio24",
 	.module		= THIS_MODULE,
 	.auto_attach	= dio24_auto_attach,
-	.detach		= dio24_detach,
+	.detach		= comedi_pcmcia_disable,
 };
 
 static int dio24_cs_attach(struct pcmcia_device *link)
diff --git a/drivers/staging/comedi/drivers/ni_labpc.c b/drivers/staging/comedi/drivers/ni_labpc.c
index a918b7ffbe22..f161e70b3a0d 100644
--- a/drivers/staging/comedi/drivers/ni_labpc.c
+++ b/drivers/staging/comedi/drivers/ni_labpc.c
@@ -1689,12 +1689,6 @@ int labpc_common_attach(struct comedi_device *dev,
 }
 EXPORT_SYMBOL_GPL(labpc_common_attach);
 
-void labpc_common_detach(struct comedi_device *dev)
-{
-	comedi_spriv_free(dev, 2);
-}
-EXPORT_SYMBOL_GPL(labpc_common_detach);
-
 #if IS_ENABLED(CONFIG_COMEDI_NI_LABPC_ISA)
 static int labpc_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 {
@@ -1747,8 +1741,6 @@ static void labpc_detach(struct comedi_device *dev)
 {
 	struct labpc_private *devpriv = dev->private;
 
-	labpc_common_detach(dev);
-
 	if (devpriv) {
 		kfree(devpriv->dma_buffer);
 		if (devpriv->dma_chan)
diff --git a/drivers/staging/comedi/drivers/ni_labpc.h b/drivers/staging/comedi/drivers/ni_labpc.h
index aa5c4d8bdf75..486589fa6fd8 100644
--- a/drivers/staging/comedi/drivers/ni_labpc.h
+++ b/drivers/staging/comedi/drivers/ni_labpc.h
@@ -86,6 +86,5 @@ struct labpc_private {
 
 int labpc_common_attach(struct comedi_device *dev,
 			unsigned int irq, unsigned long isr_flags);
-void labpc_common_detach(struct comedi_device *dev);
 
 #endif /* _NI_LABPC_H */
diff --git a/drivers/staging/comedi/drivers/ni_labpc_cs.c b/drivers/staging/comedi/drivers/ni_labpc_cs.c
index 883581eb3dbe..ce67f4bbb1f5 100644
--- a/drivers/staging/comedi/drivers/ni_labpc_cs.c
+++ b/drivers/staging/comedi/drivers/ni_labpc_cs.c
@@ -104,17 +104,11 @@ static int labpc_auto_attach(struct comedi_device *dev,
 	return labpc_common_attach(dev, link->irq, IRQF_SHARED);
 }
 
-static void labpc_detach(struct comedi_device *dev)
-{
-	labpc_common_detach(dev);
-	comedi_pcmcia_disable(dev);
-}
-
 static struct comedi_driver driver_labpc_cs = {
 	.driver_name	= "ni_labpc_cs",
 	.module		= THIS_MODULE,
 	.auto_attach	= labpc_auto_attach,
-	.detach		= labpc_detach,
+	.detach		= comedi_pcmcia_disable,
 };
 
 static int labpc_cs_attach(struct pcmcia_device *link)
diff --git a/drivers/staging/comedi/drivers/ni_labpc_pci.c b/drivers/staging/comedi/drivers/ni_labpc_pci.c
index 1f80711bf368..6c79237b2b5c 100644
--- a/drivers/staging/comedi/drivers/ni_labpc_pci.c
+++ b/drivers/staging/comedi/drivers/ni_labpc_pci.c
@@ -92,8 +92,6 @@ static void labpc_pci_detach(struct comedi_device *dev)
 {
 	struct labpc_private *devpriv = dev->private;
 
-	labpc_common_detach(dev);
-
 	if (devpriv && devpriv->mite) {
 		mite_unsetup(devpriv->mite);
 		mite_free(devpriv->mite);
diff --git a/drivers/staging/comedi/drivers/ni_mio_common.c b/drivers/staging/comedi/drivers/ni_mio_common.c
index 1e78198a2253..3e9f544e67fc 100644
--- a/drivers/staging/comedi/drivers/ni_mio_common.c
+++ b/drivers/staging/comedi/drivers/ni_mio_common.c
@@ -4072,7 +4072,6 @@ static void mio_common_detach(struct comedi_device *dev)
 			ni_gpct_device_destroy(devpriv->counter_dev);
 		}
 	}
-	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 1bcabb8901d1..cea657c7801d 100644
--- a/drivers/staging/comedi/drivers/pcl724.c
+++ b/drivers/staging/comedi/drivers/pcl724.c
@@ -136,20 +136,11 @@ static int pcl724_attach(struct comedi_device *dev,
 	return 0;
 }
 
-static void pcl724_detach(struct comedi_device *dev)
-{
-	int i;
-
-	for (i = 0; i < dev->n_subdevices; i++)
-		comedi_spriv_free(dev, i);
-	comedi_legacy_detach(dev);
-}
-
 static struct comedi_driver pcl724_driver = {
 	.driver_name	= "pcl724",
 	.module		= THIS_MODULE,
 	.attach		= pcl724_attach,
-	.detach		= pcl724_detach,
+	.detach		= comedi_legacy_detach,
 	.board_name	= &boardtypes[0].name,
 	.num_names	= ARRAY_SIZE(boardtypes),
 	.offset		= sizeof(struct pcl724_board),
diff --git a/drivers/staging/comedi/drivers/pcm3724.c b/drivers/staging/comedi/drivers/pcm3724.c
index 4ef0df30b07a..5a9cd38e15f2 100644
--- a/drivers/staging/comedi/drivers/pcm3724.c
+++ b/drivers/staging/comedi/drivers/pcm3724.c
@@ -250,20 +250,11 @@ static int pcm3724_attach(struct comedi_device *dev,
 	return 0;
 }
 
-static void pcm3724_detach(struct comedi_device *dev)
-{
-	int i;
-
-	for (i = 0; i < dev->n_subdevices; i++)
-		comedi_spriv_free(dev, i);
-	comedi_legacy_detach(dev);
-}
-
 static struct comedi_driver pcm3724_driver = {
 	.driver_name	= "pcm3724",
 	.module		= THIS_MODULE,
 	.attach		= pcm3724_attach,
-	.detach		= pcm3724_detach,
+	.detach		= comedi_legacy_detach,
 };
 module_comedi_driver(pcm3724_driver);