610 lines
19 KiB
C
610 lines
19 KiB
C
/*
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* v4l2-dv-timings - dv-timings helper functions
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*
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* Copyright 2013 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
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*
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* This program is free software; you may redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; version 2 of the License.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
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* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
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* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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* SOFTWARE.
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*
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*/
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#include <linux/module.h>
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/errno.h>
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#include <linux/videodev2.h>
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#include <linux/v4l2-dv-timings.h>
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#include <media/v4l2-dv-timings.h>
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const struct v4l2_dv_timings v4l2_dv_timings_presets[] = {
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V4L2_DV_BT_CEA_640X480P59_94,
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V4L2_DV_BT_CEA_720X480I59_94,
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V4L2_DV_BT_CEA_720X480P59_94,
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V4L2_DV_BT_CEA_720X576I50,
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V4L2_DV_BT_CEA_720X576P50,
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V4L2_DV_BT_CEA_1280X720P24,
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V4L2_DV_BT_CEA_1280X720P25,
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V4L2_DV_BT_CEA_1280X720P30,
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V4L2_DV_BT_CEA_1280X720P50,
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V4L2_DV_BT_CEA_1280X720P60,
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V4L2_DV_BT_CEA_1920X1080P24,
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V4L2_DV_BT_CEA_1920X1080P25,
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V4L2_DV_BT_CEA_1920X1080P30,
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V4L2_DV_BT_CEA_1920X1080I50,
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V4L2_DV_BT_CEA_1920X1080P50,
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V4L2_DV_BT_CEA_1920X1080I60,
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V4L2_DV_BT_CEA_1920X1080P60,
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V4L2_DV_BT_DMT_640X350P85,
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V4L2_DV_BT_DMT_640X400P85,
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V4L2_DV_BT_DMT_720X400P85,
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V4L2_DV_BT_DMT_640X480P72,
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V4L2_DV_BT_DMT_640X480P75,
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V4L2_DV_BT_DMT_640X480P85,
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V4L2_DV_BT_DMT_800X600P56,
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V4L2_DV_BT_DMT_800X600P60,
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V4L2_DV_BT_DMT_800X600P72,
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V4L2_DV_BT_DMT_800X600P75,
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V4L2_DV_BT_DMT_800X600P85,
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V4L2_DV_BT_DMT_800X600P120_RB,
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V4L2_DV_BT_DMT_848X480P60,
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V4L2_DV_BT_DMT_1024X768I43,
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V4L2_DV_BT_DMT_1024X768P60,
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V4L2_DV_BT_DMT_1024X768P70,
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V4L2_DV_BT_DMT_1024X768P75,
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V4L2_DV_BT_DMT_1024X768P85,
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V4L2_DV_BT_DMT_1024X768P120_RB,
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V4L2_DV_BT_DMT_1152X864P75,
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V4L2_DV_BT_DMT_1280X768P60_RB,
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V4L2_DV_BT_DMT_1280X768P60,
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V4L2_DV_BT_DMT_1280X768P75,
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V4L2_DV_BT_DMT_1280X768P85,
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V4L2_DV_BT_DMT_1280X768P120_RB,
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V4L2_DV_BT_DMT_1280X800P60_RB,
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V4L2_DV_BT_DMT_1280X800P60,
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V4L2_DV_BT_DMT_1280X800P75,
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V4L2_DV_BT_DMT_1280X800P85,
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V4L2_DV_BT_DMT_1280X800P120_RB,
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V4L2_DV_BT_DMT_1280X960P60,
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V4L2_DV_BT_DMT_1280X960P85,
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V4L2_DV_BT_DMT_1280X960P120_RB,
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V4L2_DV_BT_DMT_1280X1024P60,
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V4L2_DV_BT_DMT_1280X1024P75,
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V4L2_DV_BT_DMT_1280X1024P85,
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V4L2_DV_BT_DMT_1280X1024P120_RB,
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V4L2_DV_BT_DMT_1360X768P60,
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V4L2_DV_BT_DMT_1360X768P120_RB,
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V4L2_DV_BT_DMT_1366X768P60,
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V4L2_DV_BT_DMT_1366X768P60_RB,
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V4L2_DV_BT_DMT_1400X1050P60_RB,
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V4L2_DV_BT_DMT_1400X1050P60,
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V4L2_DV_BT_DMT_1400X1050P75,
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V4L2_DV_BT_DMT_1400X1050P85,
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V4L2_DV_BT_DMT_1400X1050P120_RB,
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V4L2_DV_BT_DMT_1440X900P60_RB,
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V4L2_DV_BT_DMT_1440X900P60,
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V4L2_DV_BT_DMT_1440X900P75,
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V4L2_DV_BT_DMT_1440X900P85,
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V4L2_DV_BT_DMT_1440X900P120_RB,
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V4L2_DV_BT_DMT_1600X900P60_RB,
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V4L2_DV_BT_DMT_1600X1200P60,
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V4L2_DV_BT_DMT_1600X1200P65,
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V4L2_DV_BT_DMT_1600X1200P70,
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V4L2_DV_BT_DMT_1600X1200P75,
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V4L2_DV_BT_DMT_1600X1200P85,
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V4L2_DV_BT_DMT_1600X1200P120_RB,
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V4L2_DV_BT_DMT_1680X1050P60_RB,
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V4L2_DV_BT_DMT_1680X1050P60,
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V4L2_DV_BT_DMT_1680X1050P75,
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V4L2_DV_BT_DMT_1680X1050P85,
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V4L2_DV_BT_DMT_1680X1050P120_RB,
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V4L2_DV_BT_DMT_1792X1344P60,
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V4L2_DV_BT_DMT_1792X1344P75,
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V4L2_DV_BT_DMT_1792X1344P120_RB,
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V4L2_DV_BT_DMT_1856X1392P60,
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V4L2_DV_BT_DMT_1856X1392P75,
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V4L2_DV_BT_DMT_1856X1392P120_RB,
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V4L2_DV_BT_DMT_1920X1200P60_RB,
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V4L2_DV_BT_DMT_1920X1200P60,
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V4L2_DV_BT_DMT_1920X1200P75,
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V4L2_DV_BT_DMT_1920X1200P85,
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V4L2_DV_BT_DMT_1920X1200P120_RB,
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V4L2_DV_BT_DMT_1920X1440P60,
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V4L2_DV_BT_DMT_1920X1440P75,
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V4L2_DV_BT_DMT_1920X1440P120_RB,
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V4L2_DV_BT_DMT_2048X1152P60_RB,
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V4L2_DV_BT_DMT_2560X1600P60_RB,
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V4L2_DV_BT_DMT_2560X1600P60,
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V4L2_DV_BT_DMT_2560X1600P75,
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V4L2_DV_BT_DMT_2560X1600P85,
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V4L2_DV_BT_DMT_2560X1600P120_RB,
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{ }
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};
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EXPORT_SYMBOL_GPL(v4l2_dv_timings_presets);
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bool v4l2_valid_dv_timings(const struct v4l2_dv_timings *t,
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const struct v4l2_dv_timings_cap *dvcap,
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v4l2_check_dv_timings_fnc fnc,
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void *fnc_handle)
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{
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const struct v4l2_bt_timings *bt = &t->bt;
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const struct v4l2_bt_timings_cap *cap = &dvcap->bt;
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u32 caps = cap->capabilities;
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if (t->type != V4L2_DV_BT_656_1120)
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return false;
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if (t->type != dvcap->type ||
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bt->height < cap->min_height ||
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bt->height > cap->max_height ||
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bt->width < cap->min_width ||
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bt->width > cap->max_width ||
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bt->pixelclock < cap->min_pixelclock ||
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bt->pixelclock > cap->max_pixelclock ||
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(cap->standards && !(bt->standards & cap->standards)) ||
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(bt->interlaced && !(caps & V4L2_DV_BT_CAP_INTERLACED)) ||
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(!bt->interlaced && !(caps & V4L2_DV_BT_CAP_PROGRESSIVE)))
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return false;
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return fnc == NULL || fnc(t, fnc_handle);
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}
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EXPORT_SYMBOL_GPL(v4l2_valid_dv_timings);
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int v4l2_enum_dv_timings_cap(struct v4l2_enum_dv_timings *t,
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const struct v4l2_dv_timings_cap *cap,
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v4l2_check_dv_timings_fnc fnc,
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void *fnc_handle)
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{
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u32 i, idx;
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memset(t->reserved, 0, sizeof(t->reserved));
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for (i = idx = 0; v4l2_dv_timings_presets[i].bt.width; i++) {
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if (v4l2_valid_dv_timings(v4l2_dv_timings_presets + i, cap,
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fnc, fnc_handle) &&
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idx++ == t->index) {
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t->timings = v4l2_dv_timings_presets[i];
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return 0;
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}
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}
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return -EINVAL;
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}
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EXPORT_SYMBOL_GPL(v4l2_enum_dv_timings_cap);
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bool v4l2_find_dv_timings_cap(struct v4l2_dv_timings *t,
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const struct v4l2_dv_timings_cap *cap,
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unsigned pclock_delta,
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v4l2_check_dv_timings_fnc fnc,
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void *fnc_handle)
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{
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int i;
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if (!v4l2_valid_dv_timings(t, cap, fnc, fnc_handle))
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return false;
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for (i = 0; i < v4l2_dv_timings_presets[i].bt.width; i++) {
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if (v4l2_valid_dv_timings(v4l2_dv_timings_presets + i, cap,
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fnc, fnc_handle) &&
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v4l2_match_dv_timings(t, v4l2_dv_timings_presets + i,
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pclock_delta)) {
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*t = v4l2_dv_timings_presets[i];
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return true;
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}
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}
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return false;
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}
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EXPORT_SYMBOL_GPL(v4l2_find_dv_timings_cap);
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/**
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* v4l2_match_dv_timings - check if two timings match
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* @t1 - compare this v4l2_dv_timings struct...
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* @t2 - with this struct.
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* @pclock_delta - the allowed pixelclock deviation.
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*
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* Compare t1 with t2 with a given margin of error for the pixelclock.
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*/
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bool v4l2_match_dv_timings(const struct v4l2_dv_timings *t1,
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const struct v4l2_dv_timings *t2,
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unsigned pclock_delta)
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{
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if (t1->type != t2->type || t1->type != V4L2_DV_BT_656_1120)
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return false;
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if (t1->bt.width == t2->bt.width &&
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t1->bt.height == t2->bt.height &&
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t1->bt.interlaced == t2->bt.interlaced &&
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t1->bt.polarities == t2->bt.polarities &&
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t1->bt.pixelclock >= t2->bt.pixelclock - pclock_delta &&
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t1->bt.pixelclock <= t2->bt.pixelclock + pclock_delta &&
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t1->bt.hfrontporch == t2->bt.hfrontporch &&
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t1->bt.vfrontporch == t2->bt.vfrontporch &&
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t1->bt.vsync == t2->bt.vsync &&
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t1->bt.vbackporch == t2->bt.vbackporch &&
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(!t1->bt.interlaced ||
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(t1->bt.il_vfrontporch == t2->bt.il_vfrontporch &&
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t1->bt.il_vsync == t2->bt.il_vsync &&
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t1->bt.il_vbackporch == t2->bt.il_vbackporch)))
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return true;
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return false;
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}
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EXPORT_SYMBOL_GPL(v4l2_match_dv_timings);
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void v4l2_print_dv_timings(const char *dev_prefix, const char *prefix,
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const struct v4l2_dv_timings *t, bool detailed)
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{
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const struct v4l2_bt_timings *bt = &t->bt;
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u32 htot, vtot;
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if (t->type != V4L2_DV_BT_656_1120)
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return;
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htot = V4L2_DV_BT_FRAME_WIDTH(bt);
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vtot = V4L2_DV_BT_FRAME_HEIGHT(bt);
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if (prefix == NULL)
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prefix = "";
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pr_info("%s: %s%ux%u%s%u (%ux%u)\n", dev_prefix, prefix,
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bt->width, bt->height, bt->interlaced ? "i" : "p",
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(htot * vtot) > 0 ? ((u32)bt->pixelclock / (htot * vtot)) : 0,
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htot, vtot);
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if (!detailed)
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return;
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pr_info("%s: horizontal: fp = %u, %ssync = %u, bp = %u\n",
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dev_prefix, bt->hfrontporch,
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(bt->polarities & V4L2_DV_HSYNC_POS_POL) ? "+" : "-",
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bt->hsync, bt->hbackporch);
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pr_info("%s: vertical: fp = %u, %ssync = %u, bp = %u\n",
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dev_prefix, bt->vfrontporch,
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(bt->polarities & V4L2_DV_VSYNC_POS_POL) ? "+" : "-",
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bt->vsync, bt->vbackporch);
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pr_info("%s: pixelclock: %llu\n", dev_prefix, bt->pixelclock);
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pr_info("%s: flags (0x%x):%s%s%s%s\n", dev_prefix, bt->flags,
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(bt->flags & V4L2_DV_FL_REDUCED_BLANKING) ?
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" REDUCED_BLANKING" : "",
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(bt->flags & V4L2_DV_FL_CAN_REDUCE_FPS) ?
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" CAN_REDUCE_FPS" : "",
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(bt->flags & V4L2_DV_FL_REDUCED_FPS) ?
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" REDUCED_FPS" : "",
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(bt->flags & V4L2_DV_FL_HALF_LINE) ?
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" HALF_LINE" : "");
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pr_info("%s: standards (0x%x):%s%s%s%s\n", dev_prefix, bt->standards,
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(bt->standards & V4L2_DV_BT_STD_CEA861) ? " CEA" : "",
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(bt->standards & V4L2_DV_BT_STD_DMT) ? " DMT" : "",
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(bt->standards & V4L2_DV_BT_STD_CVT) ? " CVT" : "",
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(bt->standards & V4L2_DV_BT_STD_GTF) ? " GTF" : "");
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}
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EXPORT_SYMBOL_GPL(v4l2_print_dv_timings);
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/*
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* CVT defines
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* Based on Coordinated Video Timings Standard
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* version 1.1 September 10, 2003
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*/
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#define CVT_PXL_CLK_GRAN 250000 /* pixel clock granularity */
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/* Normal blanking */
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#define CVT_MIN_V_BPORCH 7 /* lines */
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#define CVT_MIN_V_PORCH_RND 3 /* lines */
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#define CVT_MIN_VSYNC_BP 550 /* min time of vsync + back porch (us) */
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/* Normal blanking for CVT uses GTF to calculate horizontal blanking */
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#define CVT_CELL_GRAN 8 /* character cell granularity */
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#define CVT_M 600 /* blanking formula gradient */
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#define CVT_C 40 /* blanking formula offset */
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#define CVT_K 128 /* blanking formula scaling factor */
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#define CVT_J 20 /* blanking formula scaling factor */
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#define CVT_C_PRIME (((CVT_C - CVT_J) * CVT_K / 256) + CVT_J)
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#define CVT_M_PRIME (CVT_K * CVT_M / 256)
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/* Reduced Blanking */
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#define CVT_RB_MIN_V_BPORCH 7 /* lines */
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#define CVT_RB_V_FPORCH 3 /* lines */
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#define CVT_RB_MIN_V_BLANK 460 /* us */
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#define CVT_RB_H_SYNC 32 /* pixels */
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#define CVT_RB_H_BPORCH 80 /* pixels */
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#define CVT_RB_H_BLANK 160 /* pixels */
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/** v4l2_detect_cvt - detect if the given timings follow the CVT standard
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* @frame_height - the total height of the frame (including blanking) in lines.
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* @hfreq - the horizontal frequency in Hz.
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* @vsync - the height of the vertical sync in lines.
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* @polarities - the horizontal and vertical polarities (same as struct
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* v4l2_bt_timings polarities).
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* @fmt - the resulting timings.
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*
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* This function will attempt to detect if the given values correspond to a
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* valid CVT format. If so, then it will return true, and fmt will be filled
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* in with the found CVT timings.
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*/
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bool v4l2_detect_cvt(unsigned frame_height, unsigned hfreq, unsigned vsync,
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u32 polarities, struct v4l2_dv_timings *fmt)
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{
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int v_fp, v_bp, h_fp, h_bp, hsync;
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int frame_width, image_height, image_width;
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bool reduced_blanking;
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unsigned pix_clk;
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if (vsync < 4 || vsync > 7)
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return false;
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if (polarities == V4L2_DV_VSYNC_POS_POL)
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reduced_blanking = false;
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else if (polarities == V4L2_DV_HSYNC_POS_POL)
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reduced_blanking = true;
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else
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return false;
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/* Vertical */
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if (reduced_blanking) {
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v_fp = CVT_RB_V_FPORCH;
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v_bp = (CVT_RB_MIN_V_BLANK * hfreq + 1999999) / 1000000;
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v_bp -= vsync + v_fp;
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if (v_bp < CVT_RB_MIN_V_BPORCH)
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v_bp = CVT_RB_MIN_V_BPORCH;
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} else {
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v_fp = CVT_MIN_V_PORCH_RND;
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v_bp = (CVT_MIN_VSYNC_BP * hfreq + 1999999) / 1000000 - vsync;
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if (v_bp < CVT_MIN_V_BPORCH)
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v_bp = CVT_MIN_V_BPORCH;
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}
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image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1;
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/* Aspect ratio based on vsync */
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switch (vsync) {
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case 4:
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image_width = (image_height * 4) / 3;
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break;
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case 5:
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image_width = (image_height * 16) / 9;
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break;
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case 6:
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image_width = (image_height * 16) / 10;
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break;
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case 7:
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/* special case */
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if (image_height == 1024)
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image_width = (image_height * 5) / 4;
|
|
else if (image_height == 768)
|
|
image_width = (image_height * 15) / 9;
|
|
else
|
|
return false;
|
|
break;
|
|
default:
|
|
return false;
|
|
}
|
|
|
|
image_width = image_width & ~7;
|
|
|
|
/* Horizontal */
|
|
if (reduced_blanking) {
|
|
pix_clk = (image_width + CVT_RB_H_BLANK) * hfreq;
|
|
pix_clk = (pix_clk / CVT_PXL_CLK_GRAN) * CVT_PXL_CLK_GRAN;
|
|
|
|
h_bp = CVT_RB_H_BPORCH;
|
|
hsync = CVT_RB_H_SYNC;
|
|
h_fp = CVT_RB_H_BLANK - h_bp - hsync;
|
|
|
|
frame_width = image_width + CVT_RB_H_BLANK;
|
|
} else {
|
|
unsigned ideal_duty_cycle_per_myriad =
|
|
100 * CVT_C_PRIME - (CVT_M_PRIME * 100000) / hfreq;
|
|
int h_blank;
|
|
|
|
if (ideal_duty_cycle_per_myriad < 2000)
|
|
ideal_duty_cycle_per_myriad = 2000;
|
|
|
|
h_blank = image_width * ideal_duty_cycle_per_myriad /
|
|
(10000 - ideal_duty_cycle_per_myriad);
|
|
h_blank = (h_blank / (2 * CVT_CELL_GRAN)) * 2 * CVT_CELL_GRAN;
|
|
|
|
pix_clk = (image_width + h_blank) * hfreq;
|
|
pix_clk = (pix_clk / CVT_PXL_CLK_GRAN) * CVT_PXL_CLK_GRAN;
|
|
|
|
h_bp = h_blank / 2;
|
|
frame_width = image_width + h_blank;
|
|
|
|
hsync = (frame_width * 8 + 50) / 100;
|
|
hsync = hsync - hsync % CVT_CELL_GRAN;
|
|
h_fp = h_blank - hsync - h_bp;
|
|
}
|
|
|
|
fmt->type = V4L2_DV_BT_656_1120;
|
|
fmt->bt.polarities = polarities;
|
|
fmt->bt.width = image_width;
|
|
fmt->bt.height = image_height;
|
|
fmt->bt.hfrontporch = h_fp;
|
|
fmt->bt.vfrontporch = v_fp;
|
|
fmt->bt.hsync = hsync;
|
|
fmt->bt.vsync = vsync;
|
|
fmt->bt.hbackporch = frame_width - image_width - h_fp - hsync;
|
|
fmt->bt.vbackporch = frame_height - image_height - v_fp - vsync;
|
|
fmt->bt.pixelclock = pix_clk;
|
|
fmt->bt.standards = V4L2_DV_BT_STD_CVT;
|
|
if (reduced_blanking)
|
|
fmt->bt.flags |= V4L2_DV_FL_REDUCED_BLANKING;
|
|
return true;
|
|
}
|
|
EXPORT_SYMBOL_GPL(v4l2_detect_cvt);
|
|
|
|
/*
|
|
* GTF defines
|
|
* Based on Generalized Timing Formula Standard
|
|
* Version 1.1 September 2, 1999
|
|
*/
|
|
|
|
#define GTF_PXL_CLK_GRAN 250000 /* pixel clock granularity */
|
|
|
|
#define GTF_MIN_VSYNC_BP 550 /* min time of vsync + back porch (us) */
|
|
#define GTF_V_FP 1 /* vertical front porch (lines) */
|
|
#define GTF_CELL_GRAN 8 /* character cell granularity */
|
|
|
|
/* Default */
|
|
#define GTF_D_M 600 /* blanking formula gradient */
|
|
#define GTF_D_C 40 /* blanking formula offset */
|
|
#define GTF_D_K 128 /* blanking formula scaling factor */
|
|
#define GTF_D_J 20 /* blanking formula scaling factor */
|
|
#define GTF_D_C_PRIME ((((GTF_D_C - GTF_D_J) * GTF_D_K) / 256) + GTF_D_J)
|
|
#define GTF_D_M_PRIME ((GTF_D_K * GTF_D_M) / 256)
|
|
|
|
/* Secondary */
|
|
#define GTF_S_M 3600 /* blanking formula gradient */
|
|
#define GTF_S_C 40 /* blanking formula offset */
|
|
#define GTF_S_K 128 /* blanking formula scaling factor */
|
|
#define GTF_S_J 35 /* blanking formula scaling factor */
|
|
#define GTF_S_C_PRIME ((((GTF_S_C - GTF_S_J) * GTF_S_K) / 256) + GTF_S_J)
|
|
#define GTF_S_M_PRIME ((GTF_S_K * GTF_S_M) / 256)
|
|
|
|
/** v4l2_detect_gtf - detect if the given timings follow the GTF standard
|
|
* @frame_height - the total height of the frame (including blanking) in lines.
|
|
* @hfreq - the horizontal frequency in Hz.
|
|
* @vsync - the height of the vertical sync in lines.
|
|
* @polarities - the horizontal and vertical polarities (same as struct
|
|
* v4l2_bt_timings polarities).
|
|
* @aspect - preferred aspect ratio. GTF has no method of determining the
|
|
* aspect ratio in order to derive the image width from the
|
|
* image height, so it has to be passed explicitly. Usually
|
|
* the native screen aspect ratio is used for this. If it
|
|
* is not filled in correctly, then 16:9 will be assumed.
|
|
* @fmt - the resulting timings.
|
|
*
|
|
* This function will attempt to detect if the given values correspond to a
|
|
* valid GTF format. If so, then it will return true, and fmt will be filled
|
|
* in with the found GTF timings.
|
|
*/
|
|
bool v4l2_detect_gtf(unsigned frame_height,
|
|
unsigned hfreq,
|
|
unsigned vsync,
|
|
u32 polarities,
|
|
struct v4l2_fract aspect,
|
|
struct v4l2_dv_timings *fmt)
|
|
{
|
|
int pix_clk;
|
|
int v_fp, v_bp, h_fp, hsync;
|
|
int frame_width, image_height, image_width;
|
|
bool default_gtf;
|
|
int h_blank;
|
|
|
|
if (vsync != 3)
|
|
return false;
|
|
|
|
if (polarities == V4L2_DV_VSYNC_POS_POL)
|
|
default_gtf = true;
|
|
else if (polarities == V4L2_DV_HSYNC_POS_POL)
|
|
default_gtf = false;
|
|
else
|
|
return false;
|
|
|
|
/* Vertical */
|
|
v_fp = GTF_V_FP;
|
|
v_bp = (GTF_MIN_VSYNC_BP * hfreq + 999999) / 1000000 - vsync;
|
|
image_height = (frame_height - v_fp - vsync - v_bp + 1) & ~0x1;
|
|
|
|
if (aspect.numerator == 0 || aspect.denominator == 0) {
|
|
aspect.numerator = 16;
|
|
aspect.denominator = 9;
|
|
}
|
|
image_width = ((image_height * aspect.numerator) / aspect.denominator);
|
|
|
|
/* Horizontal */
|
|
if (default_gtf)
|
|
h_blank = ((image_width * GTF_D_C_PRIME * hfreq) -
|
|
(image_width * GTF_D_M_PRIME * 1000) +
|
|
(hfreq * (100 - GTF_D_C_PRIME) + GTF_D_M_PRIME * 1000) / 2) /
|
|
(hfreq * (100 - GTF_D_C_PRIME) + GTF_D_M_PRIME * 1000);
|
|
else
|
|
h_blank = ((image_width * GTF_S_C_PRIME * hfreq) -
|
|
(image_width * GTF_S_M_PRIME * 1000) +
|
|
(hfreq * (100 - GTF_S_C_PRIME) + GTF_S_M_PRIME * 1000) / 2) /
|
|
(hfreq * (100 - GTF_S_C_PRIME) + GTF_S_M_PRIME * 1000);
|
|
|
|
h_blank = h_blank - h_blank % (2 * GTF_CELL_GRAN);
|
|
frame_width = image_width + h_blank;
|
|
|
|
pix_clk = (image_width + h_blank) * hfreq;
|
|
pix_clk = pix_clk / GTF_PXL_CLK_GRAN * GTF_PXL_CLK_GRAN;
|
|
|
|
hsync = (frame_width * 8 + 50) / 100;
|
|
hsync = hsync - hsync % GTF_CELL_GRAN;
|
|
|
|
h_fp = h_blank / 2 - hsync;
|
|
|
|
fmt->type = V4L2_DV_BT_656_1120;
|
|
fmt->bt.polarities = polarities;
|
|
fmt->bt.width = image_width;
|
|
fmt->bt.height = image_height;
|
|
fmt->bt.hfrontporch = h_fp;
|
|
fmt->bt.vfrontporch = v_fp;
|
|
fmt->bt.hsync = hsync;
|
|
fmt->bt.vsync = vsync;
|
|
fmt->bt.hbackporch = frame_width - image_width - h_fp - hsync;
|
|
fmt->bt.vbackporch = frame_height - image_height - v_fp - vsync;
|
|
fmt->bt.pixelclock = pix_clk;
|
|
fmt->bt.standards = V4L2_DV_BT_STD_GTF;
|
|
if (!default_gtf)
|
|
fmt->bt.flags |= V4L2_DV_FL_REDUCED_BLANKING;
|
|
return true;
|
|
}
|
|
EXPORT_SYMBOL_GPL(v4l2_detect_gtf);
|
|
|
|
/** v4l2_calc_aspect_ratio - calculate the aspect ratio based on bytes
|
|
* 0x15 and 0x16 from the EDID.
|
|
* @hor_landscape - byte 0x15 from the EDID.
|
|
* @vert_portrait - byte 0x16 from the EDID.
|
|
*
|
|
* Determines the aspect ratio from the EDID.
|
|
* See VESA Enhanced EDID standard, release A, rev 2, section 3.6.2:
|
|
* "Horizontal and Vertical Screen Size or Aspect Ratio"
|
|
*/
|
|
struct v4l2_fract v4l2_calc_aspect_ratio(u8 hor_landscape, u8 vert_portrait)
|
|
{
|
|
struct v4l2_fract aspect = { 16, 9 };
|
|
u32 tmp;
|
|
u8 ratio;
|
|
|
|
/* Nothing filled in, fallback to 16:9 */
|
|
if (!hor_landscape && !vert_portrait)
|
|
return aspect;
|
|
/* Both filled in, so they are interpreted as the screen size in cm */
|
|
if (hor_landscape && vert_portrait) {
|
|
aspect.numerator = hor_landscape;
|
|
aspect.denominator = vert_portrait;
|
|
return aspect;
|
|
}
|
|
/* Only one is filled in, so interpret them as a ratio:
|
|
(val + 99) / 100 */
|
|
ratio = hor_landscape | vert_portrait;
|
|
/* Change some rounded values into the exact aspect ratio */
|
|
if (ratio == 79) {
|
|
aspect.numerator = 16;
|
|
aspect.denominator = 9;
|
|
} else if (ratio == 34) {
|
|
aspect.numerator = 4;
|
|
aspect.numerator = 3;
|
|
} else if (ratio == 68) {
|
|
aspect.numerator = 15;
|
|
aspect.numerator = 9;
|
|
} else {
|
|
aspect.numerator = hor_landscape + 99;
|
|
aspect.denominator = 100;
|
|
}
|
|
if (hor_landscape)
|
|
return aspect;
|
|
/* The aspect ratio is for portrait, so swap numerator and denominator */
|
|
tmp = aspect.denominator;
|
|
aspect.denominator = aspect.numerator;
|
|
aspect.numerator = tmp;
|
|
return aspect;
|
|
}
|
|
EXPORT_SYMBOL_GPL(v4l2_calc_aspect_ratio);
|