[PATCH v8 1/6] video: add display_timing and videomode

Steffen Trumtrar
2012-11-12T15:38:09Z

Add display_timing structure and the according helper functions. This allows
the description of a display via its supported timing parameters.

Every timing parameter can be specified as a single value or a range
<min typ max>.

Also, add helper functions to convert from display timings to a generic videomode
structure. This videomode can then be converted to the corresponding subsystem
mode representation (e.g. fb_videomode).

Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
---
drivers/video/Kconfig | 6 ++++
drivers/video/Makefile | 2 ++
drivers/video/display_timing.c | 22 +++++++++++++
drivers/video/videomode.c | 45 ++++++++++++++++++++++++++
include/linux/display_timing.h | 69 ++++++++++++++++++++++++++++++++++++++++
include/linux/videomode.h | 39 +++++++++++++++++++++++
6 files changed, 183 insertions(+)
create mode 100644 drivers/video/display_timing.c
create mode 100644 drivers/video/videomode.c
create mode 100644 include/linux/display_timing.h
create mode 100644 include/linux/videomode.h

diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index d08d799..2a23b18 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -33,6 +33,12 @@ config VIDEO_OUTPUT_CONTROL
This framework adds support for low-level control of the video
output switch.

+config DISPLAY_TIMING
+ bool
+
+config VIDEOMODE
+ bool
+
menuconfig FB
tristate "Support for frame buffer devices"
---help---
diff --git a/drivers/video/Makefile b/drivers/video/Makefile
index 23e948e..fc30439 100644
--- a/drivers/video/Makefile
+++ b/drivers/video/Makefile
@@ -167,3 +167,5 @@ obj-$(CONFIG_FB_VIRTUAL) += vfb.o

#video output switch sysfs driver
obj-$(CONFIG_VIDEO_OUTPUT_CONTROL) += output.o
+obj-$(CONFIG_DISPLAY_TIMING) += display_timing.o
+obj-$(CONFIG_VIDEOMODE) += videomode.o
diff --git a/drivers/video/display_timing.c b/drivers/video/display_timing.c
new file mode 100644
index 0000000..04b7b69
--- /dev/null
+++ b/drivers/video/display_timing.c
@@ -0,0 +1,22 @@
+/*
+ * generic display timing functions
+ *
+ * Copyright (c) 2012 Steffen Trumtrar <s.trumtrar@pengutronix.de>, Pengutronix
+ *
+ * This file is released under the GPLv2
+ */
+
+#include <linux/display_timing.h>
+#include <linux/slab.h>
+
+void display_timings_release(struct display_timings *disp)
+{
+ if (disp->timings) {
+ unsigned int i;
+
+ for (i = 0; i < disp->num_timings; i++)
+ kfree(disp->timings[i]);
+ kfree(disp->timings);
+ }
+ kfree(disp);
+}
diff --git a/drivers/video/videomode.c b/drivers/video/videomode.c
new file mode 100644
index 0000000..087374a
--- /dev/null
+++ b/drivers/video/videomode.c
@@ -0,0 +1,45 @@
+/*
+ * generic display timing functions
+ *
+ * Copyright (c) 2012 Steffen Trumtrar <s.trumtrar@pengutronix.de>, Pengutronix
+ *
+ * This file is released under the GPLv2
+ */
+
+#include <linux/export.h>
+#include <linux/errno.h>
+#include <linux/display_timing.h>
+#include <linux/kernel.h>
+#include <linux/videomode.h>
+
+int videomode_from_timing(struct display_timings *disp, struct videomode *vm,
+ unsigned int index)
+{
+ struct display_timing *dt;
+
+ dt = display_timings_get(disp, index);
+ if (!dt)
+ return -EINVAL;
+
+ vm->pixelclock = display_timing_get_value(&dt->pixelclock, 0);
+ vm->hactive = display_timing_get_value(&dt->hactive, 0);
+ vm->hfront_porch = display_timing_get_value(&dt->hfront_porch, 0);
+ vm->hback_porch = display_timing_get_value(&dt->hback_porch, 0);
+ vm->hsync_len = display_timing_get_value(&dt->hsync_len, 0);
+
+ vm->vactive = display_timing_get_value(&dt->vactive, 0);
+ vm->vfront_porch = display_timing_get_value(&dt->vfront_porch, 0);
+ vm->vback_porch = display_timing_get_value(&dt->vback_porch, 0);
+ vm->vsync_len = display_timing_get_value(&dt->vsync_len, 0);
+
+ vm->vah = dt->vsync_pol_active;
+ vm->hah = dt->hsync_pol_active;
+ vm->de = dt->de_pol_active;
+ vm->pixelclk_pol = dt->pixelclk_pol;
+
+ vm->interlaced = dt->interlaced;
+ vm->doublescan = dt->doublescan;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(videomode_from_timing);
diff --git a/include/linux/display_timing.h b/include/linux/display_timing.h
new file mode 100644
index 0000000..0ed2a1e
--- /dev/null
+++ b/include/linux/display_timing.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright 2012 Steffen Trumtrar <s.trumtrar@pengutronix.de>
+ *
+ * description of display timings
+ *
+ * This file is released under the GPLv2
+ */
+
+#ifndef __LINUX_DISPLAY_TIMINGS_H
+#define __LINUX_DISPLAY_TIMINGS_H
+
+#include <linux/types.h>
+
+struct timing_entry {
+ u32 min;
+ u32 typ;
+ u32 max;
+};
+
+struct display_timing {
+ struct timing_entry pixelclock;
+
+ struct timing_entry hactive;
+ struct timing_entry hfront_porch;
+ struct timing_entry hback_porch;
+ struct timing_entry hsync_len;
+
+ struct timing_entry vactive;
+ struct timing_entry vfront_porch;
+ struct timing_entry vback_porch;
+ struct timing_entry vsync_len;
+
+ unsigned int vsync_pol_active;
+ unsigned int hsync_pol_active;
+ unsigned int de_pol_active;
+ unsigned int pixelclk_pol;
+ bool interlaced;
+ bool doublescan;
+};
+
+struct display_timings {
+ unsigned int num_timings;
+ unsigned int native_mode;
+
+ struct display_timing **timings;
+};
+
+/* placeholder function until ranges are really needed
+ * the index parameter should then be used to select one of [min typ max]
+ */
+static inline u32 display_timing_get_value(struct timing_entry *te,
+ unsigned int index)
+{
+ return te->typ;
+}
+
+static inline struct display_timing *display_timings_get(struct display_timings *disp,
+ unsigned int index)
+{
+ if (disp->num_timings > index)
+ return disp->timings[index];
+ else
+ return NULL;
+}
+
+void timings_release(struct display_timings *disp);
+void display_timings_release(struct display_timings *disp);
+
+#endif
diff --git a/include/linux/videomode.h b/include/linux/videomode.h
new file mode 100644
index 0000000..0b87fbb
--- /dev/null
+++ b/include/linux/videomode.h
@@ -0,0 +1,39 @@
+/*
+ * Copyright 2012 Steffen Trumtrar <s.trumtrar@pengutronix.de>
+ *
+ * generic videomode description
+ *
+ * This file is released under the GPLv2
+ */
+
+#ifndef __LINUX_VIDEOMODE_H
+#define __LINUX_VIDEOMODE_H
+
+#include <linux/display_timing.h>
+
+struct videomode {
+ u32 pixelclock;
+ u32 refreshrate;
+
+ u32 hactive;
+ u32 hfront_porch;
+ u32 hback_porch;
+ u32 hsync_len;
+
+ u32 vactive;
+ u32 vfront_porch;
+ u32 vback_porch;
+ u32 vsync_len;
+
+ u32 hah;
+ u32 vah;
+ u32 de;
+ u32 pixelclk_pol;
+
+ bool interlaced;
+ bool doublescan;
+};
+
+int videomode_from_timing(struct display_timings *disp, struct videomode *vm,
+ unsigned int index);
+#endif
--
1.7.10.4