viafb: add interface for output device configuration

This patch extends the proc entry to contain a possibility to view and
change the output devices for each IGA. This is useful for debugging
output problems as it provides a reliable way to query which low level
devices are active after VIAs output device configuration nightmare
happended. It's as well suitable for daily use as one can change the
output configuration on the fly for example to connect a projector.
At the moment it's still unstable. The reason is that we have to handle
a bunch of undocumented output devices (those without a proper name) and
that this patch is the first step to collect and verify the needed
information. Basically the only configuration change that is expected to
work at the moment is switching output devices between IGA1 and IGA2.

Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Cc: Joseph Chan <JosephChan@via.com.tw>
Cc: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/video/via/hw.h b/drivers/video/via/hw.h
index 45dee39a8b23..657dbd64a089 100644
--- a/drivers/video/via/hw.h
+++ b/drivers/video/via/hw.h
@@ -22,6 +22,8 @@
 #ifndef __HW_H__
 #define __HW_H__
 
+#include <linux/seq_file.h>
+
 #include "viamode.h"
 #include "global.h"
 #include "via_modesetting.h"
@@ -882,6 +884,11 @@ struct pci_device_id_info {
         u32 chip_index;
 };
 
+struct via_device_mapping {
+        u32 device;
+        const char *name;
+};
+
 extern unsigned int viafb_second_virtual_xres;
 extern int viafb_SAMM_ON;
 extern int viafb_dual_fb;
@@ -899,6 +906,9 @@ void viafb_load_reg(int timing_value, int viafb_load_reg_num,
               int io_type);
 void viafb_crt_disable(void);
 void viafb_crt_enable(void);
+void via_set_source(u32 devices, u8 iga);
+u32 via_parse_odev(char *input, char **end);
+void via_odev_to_seq(struct seq_file *m, u32 odev);
 void init_ad9389(void);
 /* Access I/O Function */
 void viafb_lock_crt(void);