Merge master.kernel.org:/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog

[powerpc.git] / drivers / media / common / ir-common.c

diff --git a/drivers/media/common/ir-common.c b/drivers/media/common/ir-common.c
index ab7a1fb..a0e700d 100644 (file)
--- a/drivers/media/common/ir-common.c
+++ b/drivers/media/common/ir-common.c
@@ -1,5 +1,4 @@
 /*
- * $Id: ir-common.c,v 1.11 2005/07/07 14:44:43 mchehab Exp $
  *
  * some common structs and functions to handle infrared remotes via
  * input layer ...
@@ -335,6 +334,72 @@ int ir_dump_samples(u32 *samples, int count)
        return 0;
 }
 
+/* decode raw samples, pulse distance coding used by NEC remotes */
+int ir_decode_pulsedistance(u32 *samples, int count, int low, int high)
+{
+       int i,last,bit,len;
+       u32 curBit;
+       u32 value;
+
+       /* find start burst */
+       for (i = len = 0; i < count * 32; i++) {
+               bit = getbit(samples,i);
+               if (bit) {
+                       len++;
+               } else {
+                       if (len >= 29)
+                               break;
+                       len = 0;
+               }
+       }
+
+       /* start burst to short */
+       if (len < 29)
+               return 0xffffffff;
+
+       /* find start silence */
+       for (len = 0; i < count * 32; i++) {
+               bit = getbit(samples,i);
+               if (bit) {
+                       break;
+               } else {
+                       len++;
+               }
+       }
+
+       /* silence to short */
+       if (len < 7)
+               return 0xffffffff;
+
+       /* go decoding */
+       len   = 0;
+       last = 1;
+       value = 0; curBit = 1;
+       for (; i < count * 32; i++) {
+               bit  = getbit(samples,i);
+               if (last) {
+                       if(bit) {
+                               continue;
+                       } else {
+                               len = 1;
+                       }
+               } else {
+                       if (bit) {
+                               if (len > (low + high) /2)
+                                       value |= curBit;
+                               curBit <<= 1;
+                               if (curBit == 1)
+                                       break;
+                       } else {
+                               len++;
+                       }
+               }
+               last = bit;
+       }
+
+       return value;
+}
+
 /* decode raw samples, biphase coding, used by rc5 for example */
 int ir_decode_biphase(u32 *samples, int count, int low, int high)
 {
@@ -383,6 +448,7 @@ EXPORT_SYMBOL_GPL(ir_input_keydown);
 EXPORT_SYMBOL_GPL(ir_extract_bits);
 EXPORT_SYMBOL_GPL(ir_dump_samples);
 EXPORT_SYMBOL_GPL(ir_decode_biphase);
+EXPORT_SYMBOL_GPL(ir_decode_pulsedistance);
 
 /*
  * Local variables: