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Release 4.14 drivers/video/of_display_timing.c

Directory: drivers/video
 * OF helpers for parsing display timings
 * Copyright (c) 2012 Steffen Trumtrar <>, Pengutronix
 * based on of_videomode.c by Sascha Hauer <>
 * This file is released under the GPLv2
#include <linux/export.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <video/display_timing.h>
#include <video/of_display_timing.h>

 * parse_timing_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
 * Every display_timing can be specified with either just the typical value or
 * a range consisting of min/typ/max. This function helps handling this

static int parse_timing_property(const struct device_node *np, const char *name, struct timing_entry *result) { struct property *prop; int length, cells, ret; prop = of_find_property(np, name, &length); if (!prop) { pr_err("%pOF: could not find property %s\n", np, name); return -EINVAL; } cells = length / sizeof(u32); if (cells == 1) { ret = of_property_read_u32(np, name, &result->typ); result->min = result->typ; result->max = result->typ; } else if (cells == 3) { ret = of_property_read_u32_array(np, name, &result->min, cells); } else { pr_err("%pOF: illegal timing specification in %s\n", np, name); return -EINVAL; } return ret; }


Steffen Trumtrar15598.73%266.67%
Rob Herring21.27%133.33%

/** * of_parse_display_timing - parse display_timing entry from device_node * @np: device_node with the properties **/
static int of_parse_display_timing(const struct device_node *np, struct display_timing *dt) { u32 val = 0; int ret = 0; memset(dt, 0, sizeof(*dt)); ret |= parse_timing_property(np, "hback-porch", &dt->hback_porch); ret |= parse_timing_property(np, "hfront-porch", &dt->hfront_porch); ret |= parse_timing_property(np, "hactive", &dt->hactive); ret |= parse_timing_property(np, "hsync-len", &dt->hsync_len); ret |= parse_timing_property(np, "vback-porch", &dt->vback_porch); ret |= parse_timing_property(np, "vfront-porch", &dt->vfront_porch); ret |= parse_timing_property(np, "vactive", &dt->vactive); ret |= parse_timing_property(np, "vsync-len", &dt->vsync_len); ret |= parse_timing_property(np, "clock-frequency", &dt->pixelclock); dt->flags = 0; if (!of_property_read_u32(np, "vsync-active", &val)) dt->flags |= val ? DISPLAY_FLAGS_VSYNC_HIGH : DISPLAY_FLAGS_VSYNC_LOW; if (!of_property_read_u32(np, "hsync-active", &val)) dt->flags |= val ? DISPLAY_FLAGS_HSYNC_HIGH : DISPLAY_FLAGS_HSYNC_LOW; if (!of_property_read_u32(np, "de-active", &val)) dt->flags |= val ? DISPLAY_FLAGS_DE_HIGH : DISPLAY_FLAGS_DE_LOW; if (!of_property_read_u32(np, "pixelclk-active", &val)) dt->flags |= val ? DISPLAY_FLAGS_PIXDATA_POSEDGE : DISPLAY_FLAGS_PIXDATA_NEGEDGE; if (!of_property_read_u32(np, "syncclk-active", &val)) dt->flags |= val ? DISPLAY_FLAGS_SYNC_POSEDGE : DISPLAY_FLAGS_SYNC_NEGEDGE; else if (dt->flags & (DISPLAY_FLAGS_PIXDATA_POSEDGE | DISPLAY_FLAGS_PIXDATA_NEGEDGE)) dt->flags |= dt->flags & DISPLAY_FLAGS_PIXDATA_POSEDGE ? DISPLAY_FLAGS_SYNC_POSEDGE : DISPLAY_FLAGS_SYNC_NEGEDGE; if (of_property_read_bool(np, "interlaced")) dt->flags |= DISPLAY_FLAGS_INTERLACED; if (of_property_read_bool(np, "doublescan")) dt->flags |= DISPLAY_FLAGS_DOUBLESCAN; if (of_property_read_bool(np, "doubleclk")) dt->flags |= DISPLAY_FLAGS_DOUBLECLK; if (ret) { pr_err("%pOF: error reading timing properties\n", np); return -EINVAL; } return 0; }


Steffen Trumtrar30480.21%337.50%
Peter Ujfalusi5013.19%112.50%
Tomi Valkeinen246.33%337.50%
Rob Herring10.26%112.50%

/** * of_get_display_timing - parse a display_timing entry * @np: device_node with the timing subnode * @name: name of the timing node * @dt: display_timing struct to fill **/
int of_get_display_timing(const struct device_node *np, const char *name, struct display_timing *dt) { struct device_node *timing_np; if (!np) return -EINVAL; timing_np = of_get_child_by_name(np, name); if (!timing_np) { pr_err("%pOF: could not find node '%s'\n", np, name); return -ENOENT; } return of_parse_display_timing(timing_np, dt); }


Tomi Valkeinen6995.83%125.00%
Rob Herring11.39%125.00%
Laurent Pinchart11.39%125.00%
Andrzej Hajda11.39%125.00%

EXPORT_SYMBOL_GPL(of_get_display_timing); /** * of_get_display_timings - parse all display_timing entries from a device_node * @np: device_node with the subnodes **/
struct display_timings *of_get_display_timings(const struct device_node *np) { struct device_node *timings_np; struct device_node *entry; struct device_node *native_mode; struct display_timings *disp; if (!np) return NULL; timings_np = of_get_child_by_name(np, "display-timings"); if (!timings_np) { pr_err("%pOF: could not find display-timings node\n", np); return NULL; } disp = kzalloc(sizeof(*disp), GFP_KERNEL); if (!disp) { pr_err("%pOF: could not allocate struct disp'\n", np); goto dispfail; } entry = of_parse_phandle(timings_np, "native-mode", 0); /* assume first child as native mode if none provided */ if (!entry) entry = of_get_next_child(timings_np, NULL); /* if there is no child, it is useless to go on */ if (!entry) { pr_err("%pOF: no timing specifications given\n", np); goto entryfail; } pr_debug("%pOF: using %s as default timing\n", np, entry->name); native_mode = entry; disp->num_timings = of_get_child_count(timings_np); if (disp->num_timings == 0) { /* should never happen, as entry was already found above */ pr_err("%pOF: no timings specified\n", np); goto entryfail; } disp->timings = kzalloc(sizeof(struct display_timing *) * disp->num_timings, GFP_KERNEL); if (!disp->timings) { pr_err("%pOF: could not allocate timings array\n", np); goto entryfail; } disp->num_timings = 0; disp->native_mode = 0; for_each_child_of_node(timings_np, entry) { struct display_timing *dt; int r; dt = kzalloc(sizeof(*dt), GFP_KERNEL); if (!dt) { pr_err("%pOF: could not allocate display_timing struct\n", np); goto timingfail; } r = of_parse_display_timing(entry, dt); if (r) { /* * to not encourage wrong devicetrees, fail in case of * an error */ pr_err("%pOF: error in timing %d\n", np, disp->num_timings + 1); kfree(dt); goto timingfail; } if (native_mode == entry) disp->native_mode = disp->num_timings; disp->timings[disp->num_timings] = 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_debug("%pOF: got %d timings. Using timing #%d as default\n", np, disp->num_timings, disp->native_mode + 1); return disp; timingfail: of_node_put(native_mode); display_timings_release(disp); disp = NULL; entryfail: kfree(disp); dispfail: of_node_put(timings_np); return NULL; }


Steffen Trumtrar35886.47%111.11%
Tomi Valkeinen358.45%222.22%
Rob Herring92.17%111.11%
Sudip Mukherjee51.21%111.11%
Dan Carpenter40.97%111.11%
Laurent Pinchart10.24%111.11%
Andrzej Hajda10.24%111.11%
Boris Brezillon10.24%111.11%

EXPORT_SYMBOL_GPL(of_get_display_timings); /** * of_display_timings_exist - check if a display-timings node is provided * @np: device_node with the timing **/
int of_display_timings_exist(const struct device_node *np) { struct device_node *timings_np; if (!np) return -EINVAL; timings_np = of_parse_phandle(np, "display-timings", 0); if (!timings_np) return -EINVAL; of_node_put(timings_np); return 1; }


Steffen Trumtrar5298.11%150.00%
Laurent Pinchart11.89%150.00%


Overall Contributors

Steffen Trumtrar89880.83%323.08%
Tomi Valkeinen13512.15%323.08%
Peter Ujfalusi504.50%17.69%
Rob Herring131.17%17.69%
Sudip Mukherjee50.45%17.69%
Dan Carpenter40.36%17.69%
Laurent Pinchart30.27%17.69%
Andrzej Hajda20.18%17.69%
Boris Brezillon10.09%17.69%
Directory: drivers/video
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