diff --git a/[refs] b/[refs]
index 3e3080ec9b0c..054d0b531428 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: f5c1ca77a3b2f9b424c4f39bd71143d0ac308924
+refs/heads/master: b3b3c176d9150af542d9ba5e5b292d233883ff85
diff --git a/trunk/arch/mips/alchemy/mtx-1/board_setup.c b/trunk/arch/mips/alchemy/mtx-1/board_setup.c
index def1a75d7561..ff3697387b89 100644
--- a/trunk/arch/mips/alchemy/mtx-1/board_setup.c
+++ b/trunk/arch/mips/alchemy/mtx-1/board_setup.c
@@ -108,14 +108,10 @@ void __init board_setup(void)
 int
 mtx1_pci_idsel(unsigned int devsel, int assert)
 {
-#define MTX_IDSEL_ONLY_0_AND_3 0
-#if MTX_IDSEL_ONLY_0_AND_3
-	if (devsel != 0 && devsel != 3) {
-		printk(KERN_ERR "*** not 0 or 3\n");
-		return 0;
-	}
-#endif
-
+	/* This function is only necessary to support a proprietary Cardbus
+	 * adapter on the mtx-1 "singleboard" variant. It triggers a custom
+	 * logic chip connected to EXT_IO3 (GPIO1) to suppress IDSEL signals.
+	 */
 	if (assert && devsel != 0)
 		/* Suppress signal to Cardbus */
 		alchemy_gpio_set_value(1, 0);	/* set EXT_IO3 OFF */