drm/i915: Add support for changing LVDS panel fitting using an output property.

Previously the driver would always scale the chosen video mode to fill the
panel.  This adds 1:1 and maintain-aspect-ratio scaling modes.

v2: the drm_calloc/drm_free is replaced by kzalloc/kfree based
on Eric's suggestion.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>

1 files changed, 16 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 544d5677a2fa..88bf7521405f 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -847,9 +847,25 @@
 #define   HORIZ_INTERP_MASK     (3 << 6)
 #define   HORIZ_AUTO_SCALE      (1 << 5)
 #define   PANEL_8TO6_DITHER_ENABLE (1 << 3)
+#define   PFIT_FILTER_FUZZY     (0 << 24)
+#define   PFIT_SCALING_AUTO     (0 << 26)
+#define   PFIT_SCALING_PROGRAMMED (1 << 26)
+#define   PFIT_SCALING_PILLAR   (2 << 26)
+#define   PFIT_SCALING_LETTER   (3 << 26)
 #define PFIT_PGM_RATIOS 0x61234
 #define   PFIT_VERT_SCALE_MASK                  0xfff00000
 #define   PFIT_HORIZ_SCALE_MASK                 0x0000fff0
+/* Pre-965 */
+#define         PFIT_VERT_SCALE_SHIFT           20
+#define         PFIT_VERT_SCALE_MASK            0xfff00000
+#define         PFIT_HORIZ_SCALE_SHIFT          4
+#define         PFIT_HORIZ_SCALE_MASK           0x0000fff0
+/* 965+ */
+#define         PFIT_VERT_SCALE_SHIFT_965       16
+#define         PFIT_VERT_SCALE_MASK_965        0x1fff0000
+#define         PFIT_HORIZ_SCALE_SHIFT_965      0
+#define         PFIT_HORIZ_SCALE_MASK_965       0x00001fff
+
 #define PFIT_AUTO_RATIOS 0x61238
 
 /* Backlight control */