/**
* 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;
/**
* Connector information
*/
static drmModeConnector* connector = 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;
}
/**
* Acquire information about a connector
*
* @param connector_index The index of the connector
*/
void blueshift_drm_open_connector(int connector_index)
{
connector = drmModeGetConnector(drm_fd, *(drm_res->connectors + connector_index));
}
/**
* Release information about the connector
*/
void blueshift_drm_close_connector()
{
drmModeFreeConnector(connector);
}
/* Accurate dimension on area not covered by the edges */
/**
* Get the physical width the monitor connected to the connector
*
* @return The physical width of the monitor in millimetres, 0 if unknown or not connected
*/
int blueshift_drm_get_width()
{
return connector->mmWidth;
}
/**
* Get the physical height the monitor connected to the connector
*
* @return The physical height of the monitor in millimetres, 0 if unknown or not connected
*/
int blueshift_drm_get_height()
{
return connector->mmHeight;
}
/**
* Get whether a monitor is connected to a connector
*
* @return 1 if there is a connection, 0 otherwise, -1 if unknown
*/
int blueshift_drm_is_connected()
{
switch (connector->connection)
{
case DRM_MODE_CONNECTED:
return 1;
case DRM_MODE_DISCONNECTED:
return 0;
case DRM_MODE_UNKNOWNCONNECTION:
default:
return -1;
}
}
/**
* Get the index of the CRTC of the monitor connected to the connector
*
* @return The index of the CRTC
*/
int blueshift_drm_get_crtc()
{
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)
return crtc;
return -1;
}
/**
* Get the index of the type of the connector
*
* @return The connector type by index, 0 for unknown
*/
int blueshift_drm_get_connector_type_index()
{
return connector->connector_type;
}
/**
* Get the name of the type of the connector
*
* @return The connector type by name, "Unknown" if not identifiable,
* "Unrecognised" if Blueshift does not recognise it.
*/
const char* blueshift_drm_get_connector_type_name()
{
static const char* TYPE_NAMES[] = {
"Unknown", "VGA", "DVII", "DVID", "DVIA", "Composite", "SVIDEO", "LVDS", "Component",
"9PinDIN", "DisplayPort", "HDMIA", "HDMIB", "TV", "eDP", "VIRTUAL", "DSI"};
int type = connector->connector_type;
return (size_t)type < sizeof(TYPE_NAMES) / sizeof(char*) ? TYPE_NAMES[type] : "Unrecognised";
}
/**
* Get the current gamma ramps of the monitor connected to the connector
*
* @param crtc_index The index of the CRTC to read from
* @param gamma_size The size a gamma ramp
* @param red Storage location for the red gamma ramp
* @param green Storage location for the green gamma ramp
* @param blue Storage location for the blue gamma ramp
* @return Zero on success
*/
int blueshift_drm_get_gamma_ramps(int crtc_index, int gamma_size, uint16_t* red, uint16_t* green, uint16_t* blue)
{
int i;
/* We need to initialise it to avoid valgrind warnings */
for (i = 0; i < gamma_size; i++)
*(red + i) = *(green + i) = *(blue + i) = 0;
return drmModeCrtcGetGamma(drm_fd, *(drm_res->crtcs + crtc_index), gamma_size, red, green, blue);
}
/* Fails if inside a graphical environment */
/**
* Set the gamma ramps of the of the monitor connected to the connector
*
* @param crtc_index The index of the CRTC to read from
* @param gamma_size The size a gamma ramp
* @param red The red gamma ramp
* @param green The green gamma ramp
* @param blue The blue gamma ramp
* @return Zero on success
*/
int blueshift_drm_set_gamma_ramps(int crtc_index, int gamma_size, uint16_t* red, uint16_t* green, uint16_t* blue)
{
return drmModeCrtcSetGamma(drm_fd, *(drm_res->crtcs + crtc_index), gamma_size, red, green, blue);
}
/**
* Get the extended display identification data for the monitor connected to the connector
*
* @param edid Storage location for the EDID, it should be 128 bytes, 256 bytes + zero termination if hex
* @param size The size allocated to `edid` excluding your zero termination
* @param hex Whether to convert to hexadecimal representation, this is preferable
* @return The length of the found value, 0 if none, as if hex is false
*/
long blueshift_drm_get_edid(char* edid, long size, int hex)
{
long rc = 0;
int prop_i;
for (prop_i = 0; prop_i < connector->count_props; prop_i++)
{
drmModePropertyRes* prop = drmModeGetProperty(drm_fd, connector->props[prop_i]);
if (!strcmp("EDID", prop->name))
{
drmModePropertyBlobRes* blob = drmModeGetPropertyBlob(drm_fd, connector->prop_values[prop_i]);
if (hex)
{
rc += blob->length;
uint32_t n = size / 2;
uint32_t i;
if (n < blob->length)
n = blob->length;
for (i = 0; i < n ; i++)
{
*(edid + i * 2 + 0) = "0123456789abcdef"[(*((char*)(blob->data) + i) >> 4) & 15];
*(edid + i * 2 + 1) = "0123456789abcdef"[(*((char*)(blob->data) + i) >> 0) & 15];
}
}
else
memcpy(edid, blob->data, (blob->length < size ? blob->length : size) * sizeof(char));
drmModeFreePropertyBlob(blob);
prop_i = connector->count_props; /* stop to for loop */
}
drmModeFreeProperty(prop);
}
return rc;
}
int main(int argc, char** argv)
{
int card_n = blueshift_drm_card_count();
int card_i;
(void) argc;
(void) argv;
printf("Card count: %i\n", card_n);
for (card_i = 0; card_i < card_n; card_i++)
{
int connector_n;
int connector_i;
printf("Card: %i\n", card_i);
blueshift_drm_open(0);
blueshift_drm_update();
connector_n = blueshift_drm_connector_count();
printf(" CRTC count: %i\n", blueshift_drm_crtc_count());
printf(" Connector count: %i\n", connector_n);
for (connector_i = 0; connector_i < connector_n; connector_i++)
{
int crtc;
blueshift_drm_open_connector(connector_i);
printf(" Connector: %i\n",
connector_i);
printf(" Connected: %i\n",
blueshift_drm_is_connected());
printf(" Connector type: %s (%i)\n",
blueshift_drm_get_connector_type_name(),
blueshift_drm_get_connector_type_index());
if (blueshift_drm_is_connected() == 1)
{
long size = 128;
char* edid = malloc((size * 2 + 1) * sizeof(char));
long n;
printf(" Physical size: %i mm by %i mm\n",
blueshift_drm_get_width(),
blueshift_drm_get_height());
if ((n = blueshift_drm_get_edid(edid, size, 1)))
{
if (n > size)
{
size = n;
edid = realloc(edid, (size * 2 + 1) * sizeof(char));
blueshift_drm_get_edid(edid, size, 1);
}
*(edid + n * 2) = 0;
printf(" EDID: %s\n", edid);
}
free(edid);
if ((crtc = blueshift_drm_get_crtc()) >= 0)
{
int gamma_size = blueshift_drm_gamma_size(crtc);
uint16_t* red = alloca(3 * gamma_size * sizeof(uint16_t));
uint16_t* green = red + gamma_size;
uint16_t* blue = green + gamma_size;
printf(" CRTC: %i\n", crtc);
printf(" Gamma size: %i\n", gamma_size);
if (!blueshift_drm_get_gamma_ramps(crtc, gamma_size, red, green, blue))
{
int j;
printf(" Red:");
for (j = 0; j < gamma_size; j++)
printf(" %u", *(red + j));
printf("\n Green:");
for (j = 0; j < gamma_size; j++)
printf(" %u", *(green + j));
printf("\n Blue:");
for (j = 0; j < gamma_size; j++)
printf(" %u", *(blue + j));
printf("\n");
for (j = 0; j < gamma_size; j++)
*(red + j) /= 2;
for (j = 0; j < gamma_size; j++)
*(green + j) /= 2;
for (j = 0; j < gamma_size; j++)
*(blue + j) /= 2;
blueshift_drm_set_gamma_ramps(crtc, gamma_size, red, green, blue);
}
}
}
blueshift_drm_close_connector();
}
}
blueshift_drm_close();
return 0;
}
