viafb: add X server compatibility mode

This patch adds a config option to be compatible with X servers like
OpenChrome. This is required as for example the X server does not
handle things like disabled IGAs/PLLs resulting in a potential
freeze on X startup. With this option disabled we can provide some
nice features like power management and not reinitializing the
hardware on every mode switch (taking long time, causing flickering).

Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>

diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 6bafb51..4923b5e 100644 (file)
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -1607,6 +1607,17 @@ config FB_VIA_DIRECT_PROCFS
          correct output device configuration.
          Its use is strongly discouraged.
 
+config FB_VIA_X_COMPATIBILITY
+       bool "X server compatibility"
+       depends on FB_VIA
+       default n
+       help
+         This option reduces the functionality (power saving, ...) of the
+         framebuffer to avoid negative impact on the OpenChrome X server.
+         If you use any X server other than fbdev you should enable this
+         otherwise it should be safe to disable it and allow using all
+         features.
+
 endif
 
 config FB_NEOMAGIC

diff --git a/drivers/video/via/hw.c b/drivers/video/via/hw.c
index e531147..104f3e1 100644 (file)
--- a/drivers/video/via/hw.c
+++ b/drivers/video/via/hw.c
@@ -2293,6 +2293,12 @@ int viafb_setmode(struct VideoModeTable *vmode_tbl, int video_bpp,
        clock.set_primary_clock_source(VIA_CLKSRC_X1, true);
        clock.set_secondary_clock_source(VIA_CLKSRC_X1, true);
 
+#ifdef CONFIG_FB_VIA_X_COMPATIBILITY
+       clock.set_primary_pll_state(VIA_STATE_ON);
+       clock.set_primary_clock_state(VIA_STATE_ON);
+       clock.set_secondary_pll_state(VIA_STATE_ON);
+       clock.set_secondary_clock_state(VIA_STATE_ON);
+#else
        if (viaparinfo->shared->iga1_devices) {
                clock.set_primary_pll_state(VIA_STATE_ON);
                clock.set_primary_clock_state(VIA_STATE_ON);
@@ -2308,6 +2314,7 @@ int viafb_setmode(struct VideoModeTable *vmode_tbl, int video_bpp,
                clock.set_secondary_pll_state(VIA_STATE_OFF);
                clock.set_secondary_clock_state(VIA_STATE_OFF);
        }
+#endif /*CONFIG_FB_VIA_X_COMPATIBILITY*/
 
        via_set_state(devices, VIA_STATE_ON);
        device_screen_on();