From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steffen Trumtrar Subject: =?UTF-8?q?=5BPATCHv15=203/7=5D=20video=3A=20add=20of=20helper=20for=20display=20timings/videomode?= Date: Mon, 26 Nov 2012 10:07:24 +0100 Message-ID: <1353920848-1705-4-git-send-email-s.trumtrar@pengutronix.de> References: <1353920848-1705-1-git-send-email-s.trumtrar@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1353920848-1705-1-git-send-email-s.trumtrar@pengutronix.de> Sender: linux-media-owner@vger.kernel.org To: devicetree-discuss@lists.ozlabs.org Cc: Steffen Trumtrar , Philipp Zabel , Rob Herring , linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org, Laurent Pinchart , Thierry Reding , Guennady Liakhovetski , linux-media@vger.kernel.org, Tomi Valkeinen , Stephen Warren , kernel@pengutronix.de, Florian Tobias Schandinat , David Airlie List-Id: devicetree@vger.kernel.org This adds support for reading display timings from DT into a struct display_timings. The of_display_timing implementation supports multiple subnodes. All children are read into an array, that can be queried. If no native mode is specified, the first subnode will be used. =46or cases where the graphics driver knows there can be only one mode description or where the driver only supports one mode, a helper function of_get_videomode is added, that gets a struct videomode from D= T. Signed-off-by: Steffen Trumtrar Signed-off-by: Philipp Zabel Acked-by: Stephen Warren Reviewed-by: Thierry Reding Acked-by: Thierry Reding Tested-by: Thierry Reding Tested-by: Philipp Zabel Reviewed-by: Laurent Pinchart Acked-by: Laurent Pinchart --- .../devicetree/bindings/video/display-timing.txt | 107 ++++++++++ drivers/video/Kconfig | 15 ++ drivers/video/Makefile | 2 + drivers/video/of_display_timing.c | 219 ++++++++++++= ++++++++ drivers/video/of_videomode.c | 54 +++++ include/linux/of_display_timing.h | 20 ++ include/linux/of_videomode.h | 18 ++ 7 files changed, 435 insertions(+) create mode 100644 Documentation/devicetree/bindings/video/display-tim= ing.txt create mode 100644 drivers/video/of_display_timing.c create mode 100644 drivers/video/of_videomode.c create mode 100644 include/linux/of_display_timing.h create mode 100644 include/linux/of_videomode.h diff --git a/Documentation/devicetree/bindings/video/display-timing.txt= b/Documentation/devicetree/bindings/video/display-timing.txt new file mode 100644 index 0000000..e238f27 --- /dev/null +++ b/Documentation/devicetree/bindings/video/display-timing.txt @@ -0,0 +1,107 @@ +display-timing bindings +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D + +display-timings node +-------------------- + +required properties: + - none + +optional properties: + - native-mode: The native mode for the display, in case multiple mode= s 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 par= ameters + in pixels + vfront-porch, vback-porch, vsync-len: vertical display timing param= eters 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-inverted: pixelclock is inverted (active on falling edge)/ + non-inverted (active on rising edge)/ + ignored (ignore property) + - interlaced (bool): boolean to enable interlaced mode + - doublescan (bool): boolean to enable doublescan mode + - doubleclk (bool) + +All the optional properties that are not bool follow the following log= ic: + <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 + + +----------+---------------------------------------------+----------= +-------+ + | | =E2=86=91 | = | | + | | |vback_porch | = | | + | | =E2=86=93 | = | | + +----------###############################################----------= +-------+ + | # =E2=86=91 # = | | + | # | # = | | + | hback # | # hfront = | hsync | + | porch # | hactive # porch = | len | + |<-------->#<---------------+--------------------------->#<-------->= |<----->| + | # | # = | | + | # |vactive # = | | + | # | # = | | + | # =E2=86=93 # = | | + +----------###############################################----------= +-------+ + | | =E2=86=91 | = | | + | | |vfront_porch | = | | + | | =E2=86=93 | = | | + +----------+---------------------------------------------+----------= +-------+ + | | =E2=86=91 | = | | + | | |vsync_len | = | | + | | =E2=86=93 | = | | + +----------+---------------------------------------------+----------= +-------+ + + +Example: + + display-timings { + native-mode =3D <&timing0>; + timing0: 1080p24 { + /* 1920x1080p24 */ + clock-frequency =3D <52000000>; + hactive =3D <1920>; + vactive =3D <1080>; + hfront-porch =3D <25>; + hback-porch =3D <25>; + hsync-len =3D <25>; + vback-porch =3D <2>; + vfront-porch =3D <2>; + vsync-len =3D <2>; + hsync-active =3D <1>; + }; + }; + +Every required property also supports the use of ranges, so the common= ly used +datasheet description with -tuples can be used. + +Example: + + timing1: timing { + /* 1920x1080p24 */ + clock-frequency =3D <148500000>; + hactive =3D <1920>; + vactive =3D <1080>; + hsync-len =3D <0 44 60>; + hfront-porch =3D <80 88 95>; + hback-porch =3D <100 148 160>; + vfront-porch =3D <0 4 6>; + vback-porch =3D <0 36 50>; + vsync-len =3D <0 5 6>; + }; diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig index 2a23b18..c000f5a 100644 --- a/drivers/video/Kconfig +++ b/drivers/video/Kconfig @@ -39,6 +39,21 @@ config DISPLAY_TIMING config VIDEOMODE bool =20 +config OF_DISPLAY_TIMING + bool "Enable device tree display timing support" + depends on OF + select DISPLAY_TIMING + help + helper to parse display timings from the devicetree + +config OF_VIDEOMODE + bool "Enable device tree videomode support" + depends on OF + select VIDEOMODE + select OF_DISPLAY_TIMING + help + helper to get videomodes from the devicetree + menuconfig FB tristate "Support for frame buffer devices" ---help--- diff --git a/drivers/video/Makefile b/drivers/video/Makefile index fc30439..b936b00 100644 --- a/drivers/video/Makefile +++ b/drivers/video/Makefile @@ -168,4 +168,6 @@ obj-$(CONFIG_FB_VIRTUAL) +=3D vfb.o #video output switch sysfs driver obj-$(CONFIG_VIDEO_OUTPUT_CONTROL) +=3D output.o obj-$(CONFIG_DISPLAY_TIMING) +=3D display_timing.o +obj-$(CONFIG_OF_DISPLAY_TIMING) +=3D of_display_timing.o obj-$(CONFIG_VIDEOMODE) +=3D videomode.o +obj-$(CONFIG_OF_VIDEOMODE) +=3D of_videomode.o diff --git a/drivers/video/of_display_timing.c b/drivers/video/of_displ= ay_timing.c new file mode 100644 index 0000000..b6c549e --- /dev/null +++ b/drivers/video/of_display_timing.c @@ -0,0 +1,219 @@ +/* + * OF helpers for parsing display timings + * + * Copyright (c) 2012 Steffen Trumtrar , Pe= ngutronix + * + * based on of_videomode.c by Sascha Hauer + * + * This file is released under the GPLv2 + */ +#include +#include +#include +#include +#include + +/** + * parse_property - parse timing_entry from device_node + * @np: device_node with the property + * @name: name of the property + * @result: will be set to the return value + * + * DESCRIPTION: + * Every display_timing can be specified with either just the typical = value or + * a range consisting of min/typ/max. This function helps handling thi= s + **/ +static int parse_property(const struct device_node *np, const char *na= me, + struct timing_entry *result) +{ + struct property *prop; + int length, cells, ret; + + prop =3D of_find_property(np, name, &length); + if (!prop) { + pr_err("%s: could not find property %s\n", __func__, name); + return -EINVAL; + } + + cells =3D length / sizeof(u32); + if (cells =3D=3D 1) { + ret =3D of_property_read_u32(np, name, &result->typ); + result->min =3D result->typ; + result->max =3D result->typ; + } else if (cells =3D=3D 3) { + ret =3D of_property_read_u32_array(np, name, &result->min, cells); + } else { + pr_err("%s: illegal timing specification in %s\n", __func__, + name); + return -EINVAL; + } + + return ret; +} + +/** + * of_get_display_timing - parse display_timing entry from device_node + * @np: device_node with the properties + **/ +static struct display_timing *of_get_display_timing(const struct devic= e_node + *np) +{ + struct display_timing *dt; + int ret =3D 0; + + dt =3D kzalloc(sizeof(*dt), GFP_KERNEL); + if (!dt) { + pr_err("%s: could not allocate display_timing struct\n", + __func__); + return NULL; + } + + ret |=3D parse_property(np, "hback-porch", &dt->hback_porch); + ret |=3D parse_property(np, "hfront-porch", &dt->hfront_porch); + ret |=3D parse_property(np, "hactive", &dt->hactive); + ret |=3D parse_property(np, "hsync-len", &dt->hsync_len); + ret |=3D parse_property(np, "vback-porch", &dt->vback_porch); + ret |=3D parse_property(np, "vfront-porch", &dt->vfront_porch); + ret |=3D parse_property(np, "vactive", &dt->vactive); + ret |=3D parse_property(np, "vsync-len", &dt->vsync_len); + ret |=3D parse_property(np, "clock-frequency", &dt->pixelclock); + + of_property_read_u32(np, "vsync-active", &dt->vsync_pol_active); + of_property_read_u32(np, "hsync-active", &dt->hsync_pol_active); + of_property_read_u32(np, "de-active", &dt->de_pol_active); + of_property_read_u32(np, "pixelclk-inverted", &dt->pixelclk_pol); + dt->interlaced =3D of_property_read_bool(np, "interlaced"); + dt->doublescan =3D of_property_read_bool(np, "doublescan"); + + if (ret) { + pr_err("%s: error reading timing properties\n", __func__); + kfree(dt); + return NULL; + } + + return dt; +} + +/** + * of_get_display_timings - parse all display_timing entries from a de= vice_node + * @np: device_node with the subnodes + **/ +struct display_timings *of_get_display_timings(struct device_node *np) +{ + struct device_node *timings_np; + struct device_node *entry; + struct device_node *native_mode; + struct display_timings *disp; + + if (!np) { + pr_err("%s: no devicenode given\n", __func__); + return NULL; + } + + timings_np =3D of_find_node_by_name(np, "display-timings"); + if (!timings_np) { + pr_err("%s: could not find display-timings node\n", __func__); + return NULL; + } + + disp =3D kzalloc(sizeof(*disp), GFP_KERNEL); + if (!disp) { + pr_err("%s: could not allocate struct disp'\n", __func__); + goto dispfail; + } + + entry =3D of_parse_phandle(timings_np, "native-mode", 0); + /* assume first child as native mode if none provided */ + if (!entry) + entry =3D of_get_next_child(np, NULL); + /* if there is no child, it is useless to go on */ + if (!entry) { + pr_err("%s: no timing specifications given\n", __func__); + goto entryfail; + } + + pr_info("%s: using %s as default timing\n", __func__, entry->name); + + native_mode =3D entry; + + disp->num_timings =3D of_get_child_count(timings_np); + if (disp->num_timings =3D=3D 0) { + /* should never happen, as entry was already found above */ + pr_err("%s: no timings specified\n", __func__); + goto entryfail; + } + + disp->timings =3D kzalloc(sizeof(struct display_timing *) * disp->num= _timings, + GFP_KERNEL); + if (!disp->timings) { + pr_err("%s: could not allocate timings array\n", __func__); + goto entryfail; + } + + disp->num_timings =3D 0; + disp->native_mode =3D 0; + + for_each_child_of_node(timings_np, entry) { + struct display_timing *dt; + + dt =3D of_get_display_timing(entry); + if (!dt) { + /* + * to not encourage wrong devicetrees, fail in case of + * an error + */ + pr_err("%s: error in timing %d\n", __func__, + disp->num_timings + 1); + goto timingfail; + } + + if (native_mode =3D=3D entry) + disp->native_mode =3D disp->num_timings; + + disp->timings[disp->num_timings] =3D dt; + disp->num_timings++; + } + of_node_put(timings_np); + /* + * native_mode points to the device_node returned by of_parse_phandle + * therefore call of_node_put on it + */ + of_node_put(native_mode); + + pr_info("%s: got %d timings. Using timing #%d as default\n", + __func__, disp->num_timings, disp->native_mode + 1); + + return disp; + +timingfail: + if (native_mode) + of_node_put(native_mode); + display_timings_release(disp); +entryfail: + if (disp) + kfree(disp); +dispfail: + of_node_put(timings_np); + return NULL; +} +EXPORT_SYMBOL_GPL(of_get_display_timings); + +/** + * of_display_timings_exists - check if a display-timings node is prov= ided + * @np: device_node with the timing + **/ +int of_display_timings_exists(struct device_node *np) +{ + struct device_node *timings_np; + + if (!np) + return -EINVAL; + + timings_np =3D of_parse_phandle(np, "display-timings", 0); + if (!timings_np) + return -EINVAL; + + of_node_put(timings_np); + return 1; +} +EXPORT_SYMBOL_GPL(of_display_timings_exists); diff --git a/drivers/video/of_videomode.c b/drivers/video/of_videomode.= c new file mode 100644 index 0000000..38d4a64 --- /dev/null +++ b/drivers/video/of_videomode.c @@ -0,0 +1,54 @@ +/* + * generic videomode helper + * + * Copyright (c) 2012 Steffen Trumtrar , Pe= ngutronix + * + * This file is released under the GPLv2 + */ +#include +#include +#include +#include +#include +#include +#include + +/** + * of_get_videomode - get the videomode # from devicetree + * @np - devicenode with the display_timings + * @vm - set to return value + * @index - index into list of display_timings + * (Set this to OF_USE_NATIVE_MODE to use whatever mode is + * specified as native mode in the DT.) + * + * DESCRIPTION: + * Get a list of all display timings and put the one + * specified by index into *vm. This function should only be used, if + * only one videomode is to be retrieved. A driver that needs to work + * with multiple/all videomodes should work with + * of_get_display_timings instead. + **/ +int of_get_videomode(struct device_node *np, struct videomode *vm, + int index) +{ + struct display_timings *disp; + int ret; + + disp =3D of_get_display_timings(np); + if (!disp) { + pr_err("%s: no timings specified\n", __func__); + return -EINVAL; + } + + if (index =3D=3D OF_USE_NATIVE_MODE) + index =3D disp->native_mode; + + ret =3D videomode_from_timing(disp, vm, index); + if (ret) + return ret; + + display_timings_release(disp); + + return 0; +} +EXPORT_SYMBOL_GPL(of_get_videomode); diff --git a/include/linux/of_display_timing.h b/include/linux/of_displ= ay_timing.h new file mode 100644 index 0000000..31e9695 --- /dev/null +++ b/include/linux/of_display_timing.h @@ -0,0 +1,20 @@ +/* + * Copyright 2012 Steffen Trumtrar + * + * display timings of helpers + * + * This file is released under the GPLv2 + */ + +#ifndef __LINUX_OF_DISPLAY_TIMING_H +#define __LINUX_OF_DISPLAY_TIMING_H + +struct device_node; +struct display_timings; + +#define OF_USE_NATIVE_MODE -1 + +struct display_timings *of_get_display_timings(struct device_node *np)= ; +int of_display_timings_exists(struct device_node *np); + +#endif diff --git a/include/linux/of_videomode.h b/include/linux/of_videomode.= h new file mode 100644 index 0000000..a07efcc --- /dev/null +++ b/include/linux/of_videomode.h @@ -0,0 +1,18 @@ +/* + * Copyright 2012 Steffen Trumtrar + * + * videomode of-helpers + * + * This file is released under the GPLv2 + */ + +#ifndef __LINUX_OF_VIDEOMODE_H +#define __LINUX_OF_VIDEOMODE_H + +struct device_node; +struct videomode; + +int of_get_videomode(struct device_node *np, struct videomode *vm, + int index); + +#endif /* __LINUX_OF_VIDEOMODE_H */ --=20 1.7.10.4