MIPS: MTX-1: cleanup and comments

Add some comments about mtx1_pci_idsel() and remove a dead block of old code.

Signed-off-by: Bruno Randolf <br1@einfach.org>
To: linux-mips@linux-mips.org
To: manuel.lauss@googlemail.com
Cc: florian@openwrt.org
Patchwork: https://patchwork.linux-mips.org/patch/1449/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --git a/arch/mips/alchemy/mtx-1/board_setup.c b/arch/mips/alchemy/mtx-1/board_setup.c
index def1a75..ff36973 100644 (file)
--- a/arch/mips/alchemy/mtx-1/board_setup.c
+++ b/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 */