commit 88039815d8868fb507eb69448f5a3a65c90b0bf2
author Clemens Ladisch <clemens@ladisch.de> Mon Sep 03 09:56:23 2007 +0200
committer Jaroslav Kysela <perex@perex.cz> Tue Oct 16 15:59:45 2007 +0200
tree c2acd01aac77c96933c15502fcf9fef28e19f1d7
parent c78c950d28df984e39ad028a90bcdadcd3eda3b6

[ALSA] cmipci: check that the legacy MIDI port works

Check that the UART_EN bit actually enabled the MPU-401 port.
Apparently, C-Media thinks that it is a good idea to be paranoid here.

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

sound/pci/cmipci.c

diff --git a/sound/pci/cmipci.c b/sound/pci/cmipci.c
index fdc4615..9149d00 100644
--- a/sound/pci/cmipci.c
+++ b/sound/pci/cmipci.c
@@ -3012,6 +3012,13 @@
 			snd_cmipci_write(cm, CM_REG_LEGACY_CTRL, val);
 			/* enable UART */
 			snd_cmipci_set_bit(cm, CM_REG_FUNCTRL1, CM_UART_EN);
+			if (inb(iomidi + 1) == 0xff) {
+				snd_printk(KERN_ERR "cannot enable MPU-401 port"
+					   " at %#lx\n", iomidi);
+				snd_cmipci_clear_bit(cm, CM_REG_FUNCTRL1,
+						     CM_UART_EN);
+				iomidi = 0;
+			}
 		}
 	}