staging: comedi: ni_daq_dio24: convert to auto attach

Convert this pcmcia driver to the comedi auto attach mechanism.

This allows getting rid of the "hack" needed to pass the pcmcia_device
pointer from the pcmcia_driver to the comedi_driver as well as the
now unnecessary boardinfo.

Check the call to subdev_8255_init() for success. That function does
a kzalloc and could return -ENOMEM.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/ni_daq_dio24.c

@@ -49,97 +49,6 @@ the PCMCIA interface.
 #include <pcmcia/cisreg.h>
 #include <pcmcia/ds.h>
 
-static struct pcmcia_device *pcmcia_cur_dev;
-
-#define DIO24_SIZE 4		/*  size of io region used by board */
-
-enum dio24_bustype { pcmcia_bustype };
-
-struct dio24_board_struct {
-	const char *name;
-	int device_id;		/*  device id for pcmcia board */
-	enum dio24_bustype bustype;	/*  PCMCIA */
-	int have_dio;		/*  have 8255 chip */
-	/*  function pointers so we can use inb/outb or readb/writeb as appropriate */
-	unsigned int (*read_byte) (unsigned int address);
-	void (*write_byte) (unsigned int byte, unsigned int address);
-};
-
-static const struct dio24_board_struct dio24_boards[] = {
-	{
-	 .name = "daqcard-dio24",
-	 .device_id = 0x475c,	/*  0x10b is manufacturer id, 0x475c is device id */
-	 .bustype = pcmcia_bustype,
-	 .have_dio = 1,
-	 },
-	{
-	 .name = "ni_daq_dio24",
-	 .device_id = 0x475c,	/*  0x10b is manufacturer id, 0x475c is device id */
-	 .bustype = pcmcia_bustype,
-	 .have_dio = 1,
-	 },
-};
-
-static int dio24_attach(struct comedi_device *dev, struct comedi_devconfig *it)
-{
-	const struct dio24_board_struct *thisboard = comedi_board(dev);
-	struct comedi_subdevice *s;
-	unsigned long iobase = 0;
-	struct pcmcia_device *link;
-	int ret;
-
-	/*  get base address, irq etc. based on bustype */
-	switch (thisboard->bustype) {
-	case pcmcia_bustype:
-		link = pcmcia_cur_dev;	/* XXX hack */
-		if (!link)
-			return -EIO;
-		iobase = link->resource[0]->start;
-		break;
-	default:
-		pr_err("bug! couldn't determine board type\n");
-		return -EINVAL;
-		break;
-	}
-	pr_debug("comedi%d: ni_daq_dio24: %s, io 0x%lx", dev->minor,
-		 thisboard->name, iobase);
-
-	if (iobase == 0) {
-		pr_err("io base address is zero!\n");
-		return -EINVAL;
-	}
-
-	dev->iobase = iobase;
-
-	dev->board_name = thisboard->name;
-
-	ret = comedi_alloc_subdevices(dev, 1);
-	if (ret)
-		return ret;
-
-	/* 8255 dio */
-	s = &dev->subdevices[0];
-	subdev_8255_init(dev, s, NULL, dev->iobase);
-
-	return 0;
-};
-
-static void dio24_detach(struct comedi_device *dev)
-{
-	if (dev->subdevices)
-		subdev_8255_cleanup(dev, &dev->subdevices[0]);
-}
-
-static struct comedi_driver driver_dio24 = {
-	.driver_name	= "ni_daq_dio24",
-	.module		= THIS_MODULE,
-	.attach		= dio24_attach,
-	.detach		= dio24_detach,
-	.num_names	= ARRAY_SIZE(dio24_boards),
-	.board_name	= &dio24_boards[0].name,
-	.offset		= sizeof(struct dio24_board_struct),
-};
-
 static int dio24_pcmcia_config_loop(struct pcmcia_device *p_dev,
 				    void *priv_data)
 {
@@ -149,42 +58,63 @@ static int dio24_pcmcia_config_loop(struct pcmcia_device *p_dev,
 	return pcmcia_request_io(p_dev);
 }
 
-static int dio24_cs_attach(struct pcmcia_device *link)
+static int dio24_auto_attach(struct comedi_device *dev,
+			     unsigned long context)
 {
+	struct pcmcia_device *link = comedi_to_pcmcia_dev(dev);
+	struct comedi_subdevice *s;
 	int ret;
 
+	dev->board_name = dev->driver->driver_name;
+
 	link->config_flags |= CONF_ENABLE_IRQ | CONF_AUTO_AUDIO |
-		CONF_AUTO_SET_IO;
+			       CONF_AUTO_SET_IO;
 
 	ret = pcmcia_loop_config(link, dio24_pcmcia_config_loop, NULL);
-	if (ret) {
+	if (ret)
-		dev_warn(&link->dev, "no configuration found\n");
+		return ret;
-		goto failed;
-	}
-
-	if (!link->irq)
-		goto failed;
 
 	ret = pcmcia_enable_device(link);
 	if (ret)
-		goto failed;
+		return ret;
+	dev->iobase = link->resource[0]->start;
 
-	pcmcia_cur_dev = link;
+	ret = comedi_alloc_subdevices(dev, 1);
+	if (ret)
+		return ret;
+
+	/* 8255 dio */
+	s = &dev->subdevices[0];
+	ret = subdev_8255_init(dev, s, NULL, dev->iobase);
+	if (ret)
+		return ret;
 
 	return 0;
-
-failed:
-	pcmcia_disable_device(link);
-	return ret;
 }
 
-static void dio24_cs_detach(struct pcmcia_device *link)
+static void dio24_detach(struct comedi_device *dev)
 {
-	pcmcia_disable_device(link);
+	struct pcmcia_device *link = comedi_to_pcmcia_dev(dev);
+
+	if (dev->subdevices)
+		subdev_8255_cleanup(dev, &dev->subdevices[0]);
+	if (dev->iobase)
+		pcmcia_disable_device(link);
+}
+
+static struct comedi_driver driver_dio24 = {
+	.driver_name	= "ni_daq_dio24",
+	.module		= THIS_MODULE,
+	.auto_attach	= dio24_auto_attach,
+	.detach		= dio24_detach,
+};
+
+static int dio24_cs_attach(struct pcmcia_device *link)
+{
+	return comedi_pcmcia_auto_config(link, &driver_dio24);
 }
 
 static const struct pcmcia_device_id dio24_cs_ids[] = {
-	/* N.B. These IDs should match those in dio24_boards */
 	PCMCIA_DEVICE_MANF_CARD(0x010b, 0x475c),	/* daqcard-dio24 */
 	PCMCIA_DEVICE_NULL
 };
@@ -195,7 +125,7 @@ static struct pcmcia_driver dio24_cs_driver = {
 	.owner		= THIS_MODULE,
 	.id_table	= dio24_cs_ids,
 	.probe		= dio24_cs_attach,
-	.remove		= dio24_cs_detach,
+	.remove		= comedi_pcmcia_auto_unconfig,
 };
 module_comedi_pcmcia_driver(driver_dio24, dio24_cs_driver);