staging: comedi: adl_pci9118: support auto-attachment

Support auto-attachment of supported PCI devices by adding the
`auto_attach()` hook (`pci9118_auto_attach()`) to the `struct
comedi_driver`.  This is called via `comedi_pci_auto_attach()` at PCI
probe time.

Previously, the driver's call to `comedi_pci_auto_config()` would fall
back to the old method of auto-attaching devices and would fail because
it couldn't find a board name matching the driver name.  The new method
doesn't care about that.

There are still a few problems.  All the boards supported by this driver
have the same PCI vendor and device ID, so it will just pick the first
supported board type, "pci9118dg".  (Other supported board types have
different AI ranges or different AI speeds, but are otherwise the same.)
Also, manual attachment of devices allows several optional features to
be configured, such as use of an external multiplexord, specified
sample&hold delays and options to ignore certain hardware errors.  These
will all be set to defaults for auto-attached devices.  A future version
of the driver may address these issues via configurable device
attributes.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/adl_pci9118.c

@@ -62,6 +62,20 @@ Configuration options:
 	256|=ignore nFull - A/D FIFO Full status
 
 */
+
+/*
+ * FIXME
+ *
+ * All the supported boards have the same PCI vendor and device IDs, so
+ * auto-attachment of PCI devices will always find the first board type.
+ *
+ * Perhaps the boards have different subdevice IDs that we could use to
+ * distinguish them?
+ *
+ * Need some device attributes so the board type can be corrected after
+ * attachment if necessary, and possibly to set other options supported by
+ * manual attachment.
+ */
 #include "../comedidev.h"
 
 #include <linux/delay.h>
@@ -232,6 +246,61 @@ struct boardtype {
 
 };
 
+static const struct boardtype boardtypes[] = {
+	{
+		.name		= "pci9118dg",
+		.device_id	= 0x80d9,
+		.iorange_amcc	= AMCC_OP_REG_SIZE,
+		.iorange_9118	= IORANGE_9118,
+		.n_aichan	= 16,
+		.n_aichand	= 8,
+		.mux_aichan	= 256,
+		.n_aichanlist	= PCI9118_CHANLEN,
+		.n_aochan	= 2,
+		.ai_maxdata	= 0x0fff,
+		.ao_maxdata	= 0x0fff,
+		.rangelist_ai	= &range_pci9118dg_hr,
+		.rangelist_ao	= &range_bipolar10,
+		.ai_ns_min	= 3000,
+		.ai_pacer_min	= 12,
+		.half_fifo_size	= 512,
+	}, {
+		.name		= "pci9118hg",
+		.device_id	= 0x80d9,
+		.iorange_amcc	= AMCC_OP_REG_SIZE,
+		.iorange_9118	= IORANGE_9118,
+		.n_aichan	= 16,
+		.n_aichand	= 8,
+		.mux_aichan	= 256,
+		.n_aichanlist	= PCI9118_CHANLEN,
+		.n_aochan	= 2,
+		.ai_maxdata	= 0x0fff,
+		.ao_maxdata	= 0x0fff,
+		.rangelist_ai	= &range_pci9118hg,
+		.rangelist_ao	= &range_bipolar10,
+		.ai_ns_min	= 3000,
+		.ai_pacer_min	= 12,
+		.half_fifo_size	= 512,
+	}, {
+		.name		= "pci9118hr",
+		.device_id	= 0x80d9,
+		.iorange_amcc	= AMCC_OP_REG_SIZE,
+		.iorange_9118	= IORANGE_9118,
+		.n_aichan	= 16,
+		.n_aichand	= 8,
+		.mux_aichan	= 256,
+		.n_aichanlist	= PCI9118_CHANLEN,
+		.n_aochan	= 2,
+		.ai_maxdata	= 0xffff,
+		.ao_maxdata	= 0x0fff,
+		.rangelist_ai	= &range_pci9118dg_hr,
+		.rangelist_ao	= &range_bipolar10,
+		.ai_ns_min	= 10000,
+		.ai_pacer_min	= 40,
+		.half_fifo_size	= 512,
+	},
+};
+
 struct pci9118_private {
 	unsigned long iobase_a;	/* base+size for AMCC chip */
 	unsigned int master;	/* master capable */
@@ -1853,6 +1922,20 @@ static int pci9118_reset(struct comedi_device *dev)
 	return 0;
 }
 
+/*
+ * FIXME - this is pretty ineffective because all the supported board types
+ * have the same device ID!
+ */
+static const struct boardtype *pci9118_find_boardinfo(struct pci_dev *pcidev)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(boardtypes); i++)
+		if (pcidev->device == boardtypes[i].device_id)
+			return &boardtypes[i];
+	return NULL;
+}
+
 static struct pci_dev *pci9118_find_pci(struct comedi_device *dev,
 					struct comedi_devconfig *it)
 {
@@ -2102,6 +2185,34 @@ static int pci9118_attach(struct comedi_device *dev,
 				     softsshdelay, hw_err_mask);
 }
 
+static int __devinit pci9118_auto_attach(struct comedi_device *dev,
+					 unsigned long context_unused)
+{
+	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
+	struct pci9118_private *devpriv;
+
+	devpriv = kzalloc(sizeof(*devpriv), GFP_KERNEL);
+	if (!devpriv)
+		return -ENOMEM;
+	dev->private = devpriv;
+
+	dev->board_ptr = pci9118_find_boardinfo(pcidev);
+	if (dev->board_ptr == NULL) {
+		dev_err(dev->class_dev,
+			"adl_pci9118: cannot determine board type for pci %s\n",
+			pci_name(pcidev));
+		return -EINVAL;
+	}
+	/*
+	 * Need to 'get' the PCI device to match the 'put' in pci9118_detach().
+	 * (The 'put' also matches the implicit 'get' by pci9118_find_pci().)
+	 */
+	pci_dev_get(pcidev);
+	/* Don't disable irq, use bus master, no external mux,
+	 * no sample-hold delay, no error mask. */
+	return pci9118_common_attach(dev, 0, 1, 0, 0, 0);
+}
+
 static void pci9118_detach(struct comedi_device *dev)
 {
 	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
@@ -2127,65 +2238,11 @@ static void pci9118_detach(struct comedi_device *dev)
 	}
 }
 
-static const struct boardtype boardtypes[] = {
-	{
-		.name		= "pci9118dg",
-		.device_id	= 0x80d9,
-		.iorange_amcc	= AMCC_OP_REG_SIZE,
-		.iorange_9118	= IORANGE_9118,
-		.n_aichan	= 16,
-		.n_aichand	= 8,
-		.mux_aichan	= 256,
-		.n_aichanlist	= PCI9118_CHANLEN,
-		.n_aochan	= 2,
-		.ai_maxdata	= 0x0fff,
-		.ao_maxdata	= 0x0fff,
-		.rangelist_ai	= &range_pci9118dg_hr,
-		.rangelist_ao	= &range_bipolar10,
-		.ai_ns_min	= 3000,
-		.ai_pacer_min	= 12,
-		.half_fifo_size	= 512,
-	}, {
-		.name		= "pci9118hg",
-		.device_id	= 0x80d9,
-		.iorange_amcc	= AMCC_OP_REG_SIZE,
-		.iorange_9118	= IORANGE_9118,
-		.n_aichan	= 16,
-		.n_aichand	= 8,
-		.mux_aichan	= 256,
-		.n_aichanlist	= PCI9118_CHANLEN,
-		.n_aochan	= 2,
-		.ai_maxdata	= 0x0fff,
-		.ao_maxdata	= 0x0fff,
-		.rangelist_ai	= &range_pci9118hg,
-		.rangelist_ao	= &range_bipolar10,
-		.ai_ns_min	= 3000,
-		.ai_pacer_min	= 12,
-		.half_fifo_size	= 512,
-	}, {
-		.name		= "pci9118hr",
-		.device_id	= 0x80d9,
-		.iorange_amcc	= AMCC_OP_REG_SIZE,
-		.iorange_9118	= IORANGE_9118,
-		.n_aichan	= 16,
-		.n_aichand	= 8,
-		.mux_aichan	= 256,
-		.n_aichanlist	= PCI9118_CHANLEN,
-		.n_aochan	= 2,
-		.ai_maxdata	= 0xffff,
-		.ao_maxdata	= 0x0fff,
-		.rangelist_ai	= &range_pci9118dg_hr,
-		.rangelist_ao	= &range_bipolar10,
-		.ai_ns_min	= 10000,
-		.ai_pacer_min	= 40,
-		.half_fifo_size	= 512,
-	},
-};
-
 static struct comedi_driver adl_pci9118_driver = {
 	.driver_name	= "adl_pci9118",
 	.module		= THIS_MODULE,
 	.attach		= pci9118_attach,
+	.auto_attach	= pci9118_auto_attach,
 	.detach		= pci9118_detach,
 	.num_names	= ARRAY_SIZE(boardtypes),
 	.board_name	= &boardtypes[0].name,