Add gamma support to ply-image.

src/ply-gamma.c

+/* ply-gamma.c - plymouth gamma setup via KMS
+ *
+ * Copyright (C) 2011, The Chromium OS Authors.
+ *
+ * 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 2, 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <xf86drm.h>
+#include <xf86drmMode.h>
+
+#include "ply-gamma.h"

[Daniel Erat, 2011/04/19 16:46:02]

nit: this include should come first

[marcheu, 2011/04/19 18:02:45]

Done.

+
+static const char* gammaRampFile = "/usr/share/color/icc/internal_display.bin";
+static const int internalPanel = 1;

[Daniel Erat, 2011/04/19 16:46:02]

name variables like_this instead of likeThis

[marcheu, 2011/04/19 18:02:45]

Done but differently per our discussion.

+
+typedef struct {
+  uint16_t *red;
+  uint16_t *green;
+  uint16_t *blue;
+} gamma_ramp;

[Daniel Erat, 2011/04/19 16:46:02]

this should be GammaRamp instead (at least, i think it makes sense to stay as
close to the C++ style guide as you can in C code)

[marcheu, 2011/04/19 18:02:45]

Done.

+
+static gamma_ramp* load_gamma_ramp(const char* file)
+{

[Daniel Erat, 2011/04/19 16:46:02]

move to end of previous line here and elsewhere

[marcheu, 2011/04/19 18:02:45]

Done.

+  const int gamma_size = 256;

[Daniel Erat, 2011/04/19 16:46:02]

kGammaSize

[marcheu, 2011/04/19 18:02:45]

Done.

+  int i, r = 0;
+
+  FILE* f = fopen(file, "rb");
+  if (!f)
+    return NULL;
+
+  unsigned char red[gamma_size], green[gamma_size], blue[gamma_size];
+
+  r += fread(red, gamma_size, 1, f);

[Daniel Erat, 2011/04/19 16:46:02]

can you s/gamma_size/sizeof(red)/ here?

[marcheu, 2011/04/19 18:02:45]

Done.

+  r += fread(green, gamma_size, 1, f);
+  r += fread(blue, gamma_size, 1, f);
+  fclose(f);
+
+  if (r != 3)
+    return NULL;
+
+  gamma_ramp* ramp = (gamma_ramp*)malloc(sizeof(gamma_ramp));
+  ramp->red = (uint16_t*)malloc(sizeof(uint16_t) * gamma_size);
+  ramp->green = (uint16_t*)malloc(sizeof(uint16_t) * gamma_size);
+  ramp->blue = (uint16_t*)malloc(sizeof(uint16_t) * gamma_size);
+
+  for(i = 0; i < gamma_size; ++i)
+    {

[Daniel Erat, 2011/04/19 16:46:02]

you know what i'm going to say here

[marcheu, 2011/04/19 18:02:45]

Done.

+      ramp->red[i]   = (uint16_t)red[i] * 257;
+      ramp->green[i] = (uint16_t)green[i] * 257;
+      ramp->blue[i]  = (uint16_t)blue[i] * 257;
+    }
+
+  return ramp;
+}
+
+static void free_gamma_ramp(gamma_ramp* ramp)
+{
+  free(ramp->red);
+  free(ramp->green);
+  free(ramp->blue);
+  free(ramp);
+}
+
+bool
+ply_gamma_set()

[Daniel Erat, 2011/04/19 16:46:02]

return type and function name should be on same line

[marcheu, 2011/04/19 18:02:45]

Done.

+{
+  int i, r;
+  drmModeCrtcPtr mode;
+  gamma_ramp* ramp;
+
+  ramp = load_gamma_ramp (gammaRampFile);

[Daniel Erat, 2011/04/19 16:46:02]

no space between function name and opening parenthesis here and elsewhere

[marcheu, 2011/04/19 18:02:45]

Done.

+
+  if (!ramp)
+    {
+      fprintf(stderr, "Unable to load gamma ramp\n");
+      return false;
+    }
+
+  int fd = drmOpen("i915", NULL);
+  if (fd < 0)
+    {
+      fprintf(stderr, "Unable to open i915 drm\n");
+      return false;
+    }
+
+  drmModeRes *resources = drmModeGetResources (fd);
+  if (!resources)
+    {
+      fprintf(stderr, "Unable to get mode resources\n");
+      drmClose(fd);
+      return false;
+    }
+
+  mode = drmModeGetCrtc (fd, resources->crtcs[internalPanel]);
+  r = drmModeCrtcSetGamma (fd,
+                           mode->crtc_id,
+                           mode->gamma_size,
+                           ramp->red,
+                           ramp->green,
+                           ramp->blue);
+
+  drmModeFreeResources(resources);
+  drmClose(fd);
+  free_gamma_ramp(ramp);
+  return r >= 0;
+}
+

[Daniel Erat, 2011/04/19 16:46:02]

remove extra newlines at end of file

[marcheu, 2011/04/19 18:02:45]

Done.

+