V4L/DVB (13609): radio-sf16fmi: add autoprobing

Add automatic probing of ports 0x284 and 0x384 to radio-sf16fmi if no card is
found using PnP.
Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Douglas Schilling Landgraf <dougsland@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/radio/Kconfig

@@ -218,10 +218,7 @@ config RADIO_SF16FMI
 	tristate "SF16-FMI/SF16-FMP Radio"
 	depends on ISA && VIDEO_V4L2
 	---help---
-	  Choose Y here if you have one of these FM radio cards.  If you
-	  compile the driver into the kernel and your card is not PnP one, you
-	  have to add "sf16fm=<io>" to the kernel command line (I/O address is
-	  0x284 or 0x384).
+	  Choose Y here if you have one of these FM radio cards.
 
 	  In order to control your radio card, you will need to use programs
 	  that are compatible with the Video For Linux API.  Information on

drivers/media/radio/radio-sf16fmi.c

@@ -54,6 +54,7 @@ struct fmi
 
 static struct fmi fmi_card;
 static struct pnp_dev *dev;
+bool pnp_attached;
 
 /* freq is in 1/16 kHz to internal number, hw precision is 50 kHz */
 /* It is only useful to give freq in interval of 800 (=0.05Mhz),
@@ -320,26 +321,54 @@ static int __init fmi_init(void)
 {
 	struct fmi *fmi = &fmi_card;
 	struct v4l2_device *v4l2_dev = &fmi->v4l2_dev;
-	int res;
+	int res, i;
+	int probe_ports[] = { 0, 0x284, 0x384 };
+
+	if (io < 0) {
+		for (i = 0; i < ARRAY_SIZE(probe_ports); i++) {
+			io = probe_ports[i];
+			if (io == 0) {
+				io = isapnp_fmi_probe();
+				if (io < 0)
+					continue;
+				pnp_attached = 1;
+			}
+			if (!request_region(io, 2, "radio-sf16fmi")) {
+				if (pnp_attached)
+					pnp_device_detach(dev);
+				io = -1;
+				continue;
+			}
+			if (pnp_attached ||
+			    ((inb(io) & 0xf9) == 0xf9 && (inb(io) & 0x4) == 0))
+				break;
+			release_region(io, 2);
+			io = -1;
+		}
+	} else {
+		if (!request_region(io, 2, "radio-sf16fmi")) {
+			printk(KERN_ERR "radio-sf16fmi: port %#x already in use\n", io);
+			return -EBUSY;
+		}
+		if (inb(io) == 0xff) {
+			printk(KERN_ERR "radio-sf16fmi: card not present at %#x\n", io);
+			release_region(io, 2);
+			return -ENODEV;
+		}
+	}
+	if (io < 0) {
+		printk(KERN_ERR "radio-sf16fmi: no cards found\n");
+		return -ENODEV;
+	}
 
-	if (io < 0)
-		io = isapnp_fmi_probe();
 	strlcpy(v4l2_dev->name, "sf16fmi", sizeof(v4l2_dev->name));
 	fmi->io = io;
-	if (fmi->io < 0) {
-		v4l2_err(v4l2_dev, "No PnP card found.\n");
-		return fmi->io;
-	}
-	if (!request_region(io, 2, "radio-sf16fmi")) {
-		v4l2_err(v4l2_dev, "port 0x%x already in use\n", fmi->io);
-		pnp_device_detach(dev);
-		return -EBUSY;
-	}
 
 	res = v4l2_device_register(NULL, v4l2_dev);
 	if (res < 0) {
 		release_region(fmi->io, 2);
-		pnp_device_detach(dev);
+		if (pnp_attached)
+			pnp_device_detach(dev);
 		v4l2_err(v4l2_dev, "Could not register v4l2_device\n");
 		return res;
 	}
@@ -356,7 +385,8 @@ static int __init fmi_init(void)
 	if (video_register_device(&fmi->vdev, VFL_TYPE_RADIO, radio_nr) < 0) {
 		v4l2_device_unregister(v4l2_dev);
 		release_region(fmi->io, 2);
-		pnp_device_detach(dev);
+		if (pnp_attached)
+			pnp_device_detach(dev);
 		return -EINVAL;
 	}
 
@@ -373,7 +403,7 @@ static void __exit fmi_exit(void)
 	video_unregister_device(&fmi->vdev);
 	v4l2_device_unregister(&fmi->v4l2_dev);
 	release_region(fmi->io, 2);
-	if (dev)
+	if (dev && pnp_attached)
 		pnp_device_detach(dev);
 }