[ALSA] cmipci: make the test for integrated MIDI port address more robust
Clemens Ladisch [Fri, 24 Aug 2007 07:18:04 +0000 (09:18 +0200)]
Unused bytes in the I/O register range are likely to have the value 0x00
instead of 0xff, so test against both values when checking for the
presence of the integrated MIDI port.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

sound/pci/cmipci.c

index 9d394c7..6021e5c 100644 (file)
@@ -2827,7 +2827,7 @@ static int __devinit snd_cmipci_create(struct snd_card *card, struct pci_dev *pc
        };
        unsigned int val = 0;
        long iomidi;
-       int integrated_midi;
+       int integrated_midi = 0;
        int pcm_index, pcm_spdif_index;
        static struct pci_device_id intel_82437vx[] = {
                { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82437VX) },
@@ -2939,11 +2939,14 @@ static int __devinit snd_cmipci_create(struct snd_card *card, struct pci_dev *pc
                return err;
        }
 
-       integrated_midi = cm->chip_version > 33 &&
-               snd_cmipci_read_b(cm, CM_REG_MPU_PCI + 1) != 0xff;
-       if (integrated_midi && mpu_port[dev] == 1)
-               iomidi = cm->iobase + CM_REG_MPU_PCI;
-       else {
+       if (cm->chip_version > 33 && mpu_port[dev] == 1) {
+               val = snd_cmipci_read_b(cm, CM_REG_MPU_PCI + 1);
+               if (val != 0x00 && val != 0xff) {
+                       iomidi = cm->iobase + CM_REG_MPU_PCI;
+                       integrated_midi = 1;
+               }
+       }
+       if (!integrated_midi) {
                iomidi = mpu_port[dev];
                switch (iomidi) {
                case 0x320: val = CM_VMPU_320; break;