video: parse the video-mode environment variable

[oweals/u-boot.git] / drivers / video / videomodes.c

diff --git a/drivers/video/videomodes.c b/drivers/video/videomodes.c
index d27ce1d2cd2a45c400df753233be499583c92774..6fe5811aec92ba4aa377f92f6c56aee2e8b8ffe8 100644 (file)
--- a/drivers/video/videomodes.c
+++ b/drivers/video/videomodes.c
@@ -1,6 +1,7 @@
 /*
  * (C) Copyright 2004
  * Pierre Aubert, Staubli Faverges , <p.aubert@staubli.com>
+ * Copyright 2011 Freescale Semiconductor, Inc.
  *
  * See file CREDITS for list of people who contributed to this
  * project.
@@ -73,6 +74,8 @@
 ****************************************************************************/
 
 #include <common.h>
+#include <linux/ctype.h>
+
 #include "videomodes.h"
 
 const struct ctfb_vesa_modes vesa_modes[VESA_MODES_COUNT] = {
@@ -206,3 +209,64 @@ int video_get_params (struct ctfb_res_modes *pPar, char *penv)
        }
        return bpp;
 }
+
+/*
+ * Parse the 'video-mode' environment variable
+ *
+ * Example: "video-mode=fslfb:1280x1024-32@60,monitor=dvi".  See
+ * doc/README.video for more information on how to set the variable.
+ *
+ * @xres: returned value of X-resolution
+ * @yres: returned value of Y-resolution
+ * @depth: returned value of color depth
+ * @freq: returned value of monitor frequency
+ * @options: pointer to any remaining options, or NULL
+ *
+ * Returns 1 if valid values were found, 0 otherwise
+ */
+int video_get_video_mode(unsigned int *xres, unsigned int *yres,
+       unsigned int *depth, unsigned int *freq, const char **options)
+{
+       char *p = getenv("video-mode");
+       if (!p)
+               return 0;
+
+       /* Skip over the driver name, which we don't care about. */
+       p = strchr(p, ':');
+       if (!p)
+               return 0;
+
+       /* Get the X-resolution*/
+       while (*p && !isdigit(*p))
+               p++;
+       *xres = simple_strtoul(p, &p, 10);
+       if (!*xres)
+               return 0;
+
+       /* Get the Y-resolution */
+       while (*p && !isdigit(*p))
+               p++;
+       *yres = simple_strtoul(p, &p, 10);
+       if (!*yres)
+               return 0;
+
+       /* Get the depth */
+       while (*p && !isdigit(*p))
+               p++;
+       *depth = simple_strtoul(p, &p, 10);
+       if (!*depth)
+               return 0;
+
+       /* Get the frequency */
+       while (*p && !isdigit(*p))
+               p++;
+       *freq = simple_strtoul(p, &p, 10);
+       if (!*freq)
+               return 0;
+
+       /* Find the extra options, if any */
+       p = strchr(p, ',');
+       *options = p ? p + 1 : NULL;
+
+       return 1;
+}