Merge tag 'of_videomode_helper' of git://git.pengutronix.de/git/str/linux into drm-next

videomode helpers for of + devicetree stuff, required for new kms drivers

(not the fbdev maintainer).

* tag 'of_videomode_helper' of git://git.pengutronix.de/git/str/linux:
  drm_modes: add of_videomode helpers
  drm_modes: add videomode helpers
  fbmon: add of_videomode helpers
  fbmon: add videomode helpers
  video: add of helper for display timings/videomode
  video: add display_timing and videomode
  viafb: rename display_timing to via_display_timing

21 files changed, 894 insertions, 13 deletions

diff --git a/Documentation/devicetree/bindings/video/display-timing.txt b/Documentation/devicetree/bindings/video/display-timing.txt
new file mode 100644
index 000000000000..150038552bc3
--- /dev/null
+++ b/Documentation/devicetree/bindings/video/display-timing.txt
@@ -0,0 +1,109 @@
+display-timing bindings
+=======================
+
+display-timings node
+--------------------
+
+required properties:
+ - none
+
+optional properties:
+ - native-mode: The native mode for the display, in case multiple modes are
+                provided. When omitted, assume the first node is the native.
+
+timing subnode
+--------------
+
+required properties:
+ - hactive, vactive: display resolution
+ - hfront-porch, hback-porch, hsync-len: horizontal display timing parameters
+   in pixels
+   vfront-porch, vback-porch, vsync-len: vertical display timing parameters in
+   lines
+ - clock-frequency: display clock in Hz
+
+optional properties:
+ - hsync-active: hsync pulse is active low/high/ignored
+ - vsync-active: vsync pulse is active low/high/ignored
+ - de-active: data-enable pulse is active low/high/ignored
+ - pixelclk-active: with
+                        - active high = drive pixel data on rising edge/
+                                        sample data on falling edge
+                        - active low  = drive pixel data on falling edge/
+                                        sample data on rising edge
+                        - ignored     = ignored
+ - interlaced (bool): boolean to enable interlaced mode
+ - doublescan (bool): boolean to enable doublescan mode
+
+All the optional properties that are not bool follow the following logic:
+    <1>: high active
+    <0>: low active
+    omitted: not used on hardware
+
+There are different ways of describing the capabilities of a display. The
+devicetree representation corresponds to the one commonly found in datasheets
+for displays. If a display supports multiple signal timings, the native-mode
+can be specified.
+
+The parameters are defined as:
+
+  +----------+-------------------------------------+----------+-------+
+  |          |        ↑                            |          |       |
+  |          |        |vback_porch                 |          |       |
+  |          |        ↓                            |          |       |
+  +----------#######################################----------+-------+
+  |          #        ↑                            #          |       |
+  |          #        |                            #          |       |
+  |  hback   #        |                            #  hfront  | hsync |
+  |   porch  #        |       hactive              #  porch   |  len  |
+  |<-------->#<-------+--------------------------->#<-------->|<----->|
+  |          #        |                            #          |       |
+  |          #        |vactive                     #          |       |
+  |          #        |                            #          |       |
+  |          #        ↓                            #          |       |
+  +----------#######################################----------+-------+
+  |          |        ↑                            |          |       |
+  |          |        |vfront_porch                |          |       |
+  |          |        ↓                            |          |       |
+  +----------+-------------------------------------+----------+-------+
+  |          |        ↑                            |          |       |
+  |          |        |vsync_len                   |          |       |
+  |          |        ↓                            |          |       |
+  +----------+-------------------------------------+----------+-------+
+
+Example:
+
+        display-timings {
+                native-mode = <&timing0>;
+                timing0: 1080p24 {
+                        /* 1920x1080p24 */
+                        clock-frequency = <52000000>;
+                        hactive = <1920>;
+                        vactive = <1080>;
+                        hfront-porch = <25>;
+                        hback-porch = <25>;
+                        hsync-len = <25>;
+                        vback-porch = <2>;
+                        vfront-porch = <2>;
+                        vsync-len = <2>;
+                        hsync-active = <1>;
+                };
+        };
+
+Every required property also supports the use of ranges, so the commonly used
+datasheet description with minimum, typical and maximum values can be used.
+
+Example:
+
+        timing1: timing {
+                /* 1920x1080p24 */
+                clock-frequency = <148500000>;
+                hactive = <1920>;
+                vactive = <1080>;
+                hsync-len = <0 44 60>;
+                hfront-porch = <80 88 95>;
+                hback-porch = <100 148 160>;
+                vfront-porch = <0 4 6>;
+                vback-porch = <0 36 50>;
+                vsync-len = <0 5 6>;
+        };
diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
index d8da30e90db5..04fa6f1808d1 100644
--- a/drivers/gpu/drm/drm_modes.c
+++ b/drivers/gpu/drm/drm_modes.c
@@ -35,6 +35,8 @@
 #include <linux/export.h>
 #include <drm/drmP.h>
 #include <drm/drm_crtc.h>
+#include <video/of_videomode.h>
+#include <video/videomode.h>
 
 /**
  * drm_mode_debug_printmodeline - debug print a mode
@@ -504,6 +506,74 @@ drm_gtf_mode(struct drm_device *dev, int hdisplay, int vdisplay, int vrefresh,
 }
 EXPORT_SYMBOL(drm_gtf_mode);
 
+#if IS_ENABLED(CONFIG_VIDEOMODE)
+int drm_display_mode_from_videomode(const struct videomode *vm,
+                                    struct drm_display_mode *dmode)
+{
+        dmode->hdisplay = vm->hactive;
+        dmode->hsync_start = dmode->hdisplay + vm->hfront_porch;
+        dmode->hsync_end = dmode->hsync_start + vm->hsync_len;
+        dmode->htotal = dmode->hsync_end + vm->hback_porch;
+
+        dmode->vdisplay = vm->vactive;
+        dmode->vsync_start = dmode->vdisplay + vm->vfront_porch;
+        dmode->vsync_end = dmode->vsync_start + vm->vsync_len;
+        dmode->vtotal = dmode->vsync_end + vm->vback_porch;
+
+        dmode->clock = vm->pixelclock / 1000;
+
+        dmode->flags = 0;
+        if (vm->dmt_flags &