Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / media / rc / img-ir / img-ir-rc6.c
diff --git a/kernel/drivers/media/rc/img-ir/img-ir-rc6.c b/kernel/drivers/media/rc/img-ir/img-ir-rc6.c
new file mode 100644 (file)
index 0000000..de1e275
--- /dev/null
@@ -0,0 +1,117 @@
+/*
+ * ImgTec IR Decoder setup for Philips RC-6 protocol.
+ *
+ * Copyright 2012-2014 Imagination Technologies Ltd.
+ *
+ * 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 of the License, or (at your
+ * option) any later version.
+ */
+
+#include "img-ir-hw.h"
+
+/* Convert RC6 data to a scancode */
+static int img_ir_rc6_scancode(int len, u64 raw, u64 enabled_protocols,
+                               struct img_ir_scancode_req *request)
+{
+       unsigned int addr, cmd, mode, trl1, trl2;
+
+       /*
+        * Due to a side effect of the decoder handling the double length
+        * Trailer bit, the header information is a bit scrambled, and the
+        * raw data is shifted incorrectly.
+        * This workaround effectively recovers the header bits.
+        *
+        * The Header field should look like this:
+        *
+        * StartBit ModeBit2 ModeBit1 ModeBit0 TrailerBit
+        *
+        * But what we get is:
+        *
+        * ModeBit2 ModeBit1 ModeBit0 TrailerBit1 TrailerBit2
+        *
+        * The start bit is not important to recover the scancode.
+        */
+
+       raw     >>= 27;
+
+       trl1    = (raw >>  17)  & 0x01;
+       trl2    = (raw >>  16)  & 0x01;
+
+       mode    = (raw >>  18)  & 0x07;
+       addr    = (raw >>   8)  & 0xff;
+       cmd     =  raw          & 0xff;
+
+       /*
+        * Due to the above explained irregularity the trailer bits cannot
+        * have the same value.
+        */
+       if (trl1 == trl2)
+               return -EINVAL;
+
+       /* Only mode 0 supported for now */
+       if (mode)
+               return -EINVAL;
+
+       request->protocol = RC_TYPE_RC6_0;
+       request->scancode = addr << 8 | cmd;
+       request->toggle   = trl2;
+       return IMG_IR_SCANCODE;
+}
+
+/* Convert RC6 scancode to RC6 data filter */
+static int img_ir_rc6_filter(const struct rc_scancode_filter *in,
+                                struct img_ir_filter *out, u64 protocols)
+{
+       /* Not supported by the hw. */
+       return -EINVAL;
+}
+
+/*
+ * RC-6 decoder
+ * see http://www.sbprojects.com/knowledge/ir/rc6.php
+ */
+struct img_ir_decoder img_ir_rc6 = {
+       .type           = RC_BIT_RC6_0,
+       .control        = {
+               .bitorien       = 1,
+               .code_type      = IMG_IR_CODETYPE_BIPHASE,
+               .decoden        = 1,
+               .decodinpol     = 1,
+       },
+       /* main timings */
+       .tolerance      = 20,
+       /*
+        * Due to a quirk in the img-ir decoder, default header values do
+        * not work, the values described below were extracted from
+        * successful RTL test cases.
+        */
+       .timings        = {
+               /* leader symbol */
+               .ldr = {
+                       .pulse  = { 650 },
+                       .space  = { 660 },
+               },
+               /* 0 symbol */
+               .s00 = {
+                       .pulse  = { 370 },
+                       .space  = { 370 },
+               },
+               /* 01 symbol */
+               .s01 = {
+                       .pulse  = { 370 },
+                       .space  = { 370 },
+               },
+               /* free time */
+               .ft  = {
+                       .minlen = 21,
+                       .maxlen = 21,
+                       .ft_min = 2666, /* 2.666 ms */
+               },
+       },
+
+       /* scancode logic */
+       .scancode       = img_ir_rc6_scancode,
+       .filter         = img_ir_rc6_filter,
+};