/**
* Copyright © 2014 Mattias Andrée (maandree@member.fsf.org)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <fcntl.h>
#include <alloca.h>
#ifndef O_CLOEXEC
#define O_CLOEXEC 02000000
#endif
/* Requires video group */
#include <xf86drm.h>
#include <xf86drmMode.h>
/**
* File descriptor for the DRM connection
*/
static int drm_fd;
/**
* DRM mode resources
*/
static drmModeRes* drm_res = NULL;
/**
* Get the number of cards present on the system
*
* @return The number of cards present on the system
*/
int blueshift_drm_card_count()
{
long maxlen = strlen(DRM_DIR_NAME) + strlen(DRM_DEV_NAME) + 10;
char* pathname = alloca(maxlen * sizeof(char));
int count = 0;
struct stat attr;
for (;;)
{
sprintf(pathname, DRM_DEV_NAME, DRM_DIR_NAME, count);
if (stat(pathname, &attr))
break;
count++;
}
return count;
}
/**
* Open connection to a graphics card
*
* @param card The index of the graphics card
* @return Zero on success
*/
int blueshift_drm_open(int card)
{
long maxlen = strlen(DRM_DIR_NAME) + strlen(DRM_DEV_NAME) + 10;
char* pathname = alloca(maxlen * sizeof(char));
sprintf(pathname, DRM_DEV_NAME, DRM_DIR_NAME, card);
drm_fd = open(pathname, O_RDWR | O_CLOEXEC);
if (drm_fd < 0)
{
perror("open");
return 1;
}
return 0;
}
/**
* Close connection to the graphics card
*/
void blueshift_drm_close()
{
drmModeFreeResources(drm_res);
close(drm_fd);
}
/**
* Update the resource, required after `blueshift_drm_open`
*/
void blueshift_drm_update()
{
if (drm_res)
drmModeFreeResources(drm_res);
drm_res = drmModeGetResources(drm_fd);
}
/**
* Return the number of CRTC:s on the opened card
*
* @return The number of CRTC:s on the opened card
*/
int blueshift_drm_crtc_count()
{
return drm_res->count_crtcs;
}
/**
* Return the number of connectors on the opened card
*
* @return The number of connectors on the opened card
*/
int blueshift_drm_connector_count()
{
return drm_res->count_connectors;
}
/**
* Return the size of the gamma ramps on a CRTC
*
* @param crtc_index The index of the CRTC
* @return The size of the gamma ramps on a CRTC
*/
int blueshift_drm_gamma_size(int crtc_index)
{
drmModeCrtc* crtc = drmModeGetCrtc(drm_fd, *(drm_res->crtcs + crtc_index));
int gamma_size;
gamma_size = crtc->gamma_size;
drmModeFreeCrtc(crtc);
return gamma_size;
}
int main(int argc, char** argv)
{
(void) argc;
(void) argv;
printf("Card count: %i\n", blueshift_drm_card_count());
blueshift_drm_open(0);
blueshift_drm_update();
printf("CRTC count: %i\n", blueshift_drm_crtc_count());
printf("Connector count: %i\n", blueshift_drm_connector_count());
printf("Gamma size: %i\n", blueshift_drm_gamma_size(0));
drmModeConnector* connector = drmModeGetConnector(drm_fd, *(drm_res->connectors + 2));
printf("Physical size: %i mm by %i mm\n", connector->mmWidth, connector->mmHeight);
/* Accurate dimension on area not covered by the edges */
printf("Connected: %i\n", connector->connection == DRM_MODE_CONNECTED);
/* DRM_MODE_DISCONNECTED DRM_MODE_UNKNOWNCONNECTION */
if (connector->connection == DRM_MODE_CONNECTED)
{
drmModeEncoder* encoder = drmModeGetEncoder(drm_fd, connector->encoder_id);
uint32_t crtc_id = encoder->crtc_id;
int crtc;
drmModeFreeEncoder(encoder);
for (crtc = 0; crtc < drm_res->count_crtcs; crtc++)
if (*(drm_res->crtcs + crtc) == crtc_id)
{
printf("CRTC: %i\n", crtc);
break;
}
if (crtc < drm_res->count_crtcs)
{
int gamma_size = blueshift_drm_gamma_size(crtc);
uint16_t* red = alloca(gamma_size * sizeof(uint16_t));
uint16_t* green = alloca(gamma_size * sizeof(uint16_t));
uint16_t* blue = alloca(gamma_size * sizeof(uint16_t));
int j;
/* We need to initialise it to avoid valgrind warnings */
for (j = 0; j < gamma_size; j++)
*(red + j) = *(green + j) = *(blue + j) = 0;
if (!drmModeCrtcGetGamma(drm_fd, crtc_id, gamma_size, red, green, blue))
{
printf("Red:");
for (j = 0; j < gamma_size; j++)
printf(" %u", *(red + j));
printf("\nGreen:");
for (j = 0; j < gamma_size; j++)
printf(" %u", *(green + j));
printf("\nBlue:");
for (j = 0; j < gamma_size; j++)
printf(" %u", *(blue + j));
printf("\n");
}
}
}
static const char* types[] = {"Unknown", "VGA", "DVII", "DVID", "DVIA", "Composite", "SVIDEO", "LVDS",
"Component", "9PinDIN", "DisplayPort", "HDMIA", "HDMIB", "TV", "eDP",
"VIRTUAL", "DSI"};
printf("Type: %s (%i)\n", types[connector->connector_type], connector->connector_type);
int i;
for (i = 0; i < connector->count_props; i++)
{
drmModePropertyRes* prop;
prop = drmModeGetProperty(drm_fd, connector->props[i]);
if (!strcmp("EDID", prop->name))
{
drmModePropertyBlobRes* blob = drmModeGetPropertyBlob(drm_fd, connector->prop_values[i]);
char* value = alloca((blob->length * 2 + 1) * sizeof(char));
uint32_t j;
for (j = 0; j < blob->length; j++)
{
*(value + j * 2 + 0) = "0123456789abcdef"[(*((char*)(blob->data) + j) >> 4) & 15];
*(value + j * 2 + 1) = "0123456789abcdef"[(*((char*)(blob->data) + j) >> 0) & 15];
}
*(value + blob->length * 2) = 0;
printf("%s: %s\n", prop->name, value);
drmModeFreePropertyBlob(blob);
}
drmModeFreeProperty(prop);
}
drmModeFreeConnector(connector);
blueshift_drm_close();
return 0;
}
