fdt_support: support adding EDID property to FDT display nodes

Boards can pass display timing info for drivers using EDID
block. Provide common function to add board specific EDID
data to the device tree. Subsequent patch makes use of this
functionality.

Detailed timing descriptor data from EDID is used for
programming the display controller. This is currently
implemented on the Linux side by the fsl-diu-fb frame
buffer driver and it is documented there in
Documentation/powerpc/dts-bindings/fsl/diu.txt.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Acked-by: Detlev Zundel <dzu@denx.de>
Cc: Gerald Van Baren <vanbaren@cideas.com>

diff --git a/common/fdt_support.c b/common/fdt_support.c
index 0ed6e77292df179b953f6d1ad760bd9e4a236ac5..9b65a8adfdec5f80423ecfd6e32c32da710e3db2 100644 (file)
--- a/common/fdt_support.c
+++ b/common/fdt_support.c
@@ -1189,3 +1189,32 @@ int fdt_alloc_phandle(void *blob)
 
        return phandle + 1;
 }
+
+#if defined(CONFIG_VIDEO)
+int fdt_add_edid(void *blob, const char *compat, unsigned char *edid_buf)
+{
+       int noff;
+       int ret;
+
+       noff = fdt_node_offset_by_compatible(blob, -1, compat);
+       if (noff != -FDT_ERR_NOTFOUND) {
+               debug("%s: %s\n", fdt_get_name(blob, noff, 0), compat);
+add_edid:
+               ret = fdt_setprop(blob, noff, "edid", edid_buf, 128);
+               if (ret == -FDT_ERR_NOSPACE) {
+                       ret = fdt_increase_size(blob, 512);
+                       if (!ret)
+                               goto add_edid;
+                       else
+                               goto err_size;
+               } else if (ret < 0) {
+                       printf("Can't add property: %s\n", fdt_strerror(ret));
+                       return ret;
+               }
+       }
+       return 0;
+err_size:
+       printf("Can't increase blob size: %s\n", fdt_strerror(ret));
+       return ret;
+}
+#endif

diff --git a/include/fdt_support.h b/include/fdt_support.h
index fd94929cefab25cbb3f670e1fbdad0cbf80499ea..deb5dda5c7619c2f27235bb3fc44b927a417186c 100644 (file)
--- a/include/fdt_support.h
+++ b/include/fdt_support.h
@@ -87,6 +87,7 @@ u64 fdt_translate_address(void *blob, int node_offset, const u32 *in_addr);
 int fdt_node_offset_by_compat_reg(void *blob, const char *compat,
                                        phys_addr_t compat_off);
 int fdt_alloc_phandle(void *blob);
+int fdt_add_edid(void *blob, const char *compat, unsigned char *buf);
 
 #endif /* ifdef CONFIG_OF_LIBFDT */
 #endif /* ifndef __FDT_SUPPORT_H */