[media] rc: img-ir: add philips rc5 decoder module

Add img-ir module for decoding Philips rc5 protocol.
Signed-off-by: Sifan Naeem <sifan.naeem@imgtec.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/rc/img-ir/Kconfig

@@ -60,3 +60,10 @@ config IR_IMG_SANYO
 	help
 	   Say Y here to enable support for the Sanyo protocol (used by Sanyo,
 	   Aiwa, Chinon remotes) in the ImgTec infrared decoder block.
+
+config IR_IMG_RC5
+	bool "Philips RC5 protocol support"
+	depends on IR_IMG_HW
+	help
+	   Say Y here to enable support for the RC5 protocol in the ImgTec
+	   infrared decoder block.

drivers/media/rc/img-ir/Makefile

@@ -6,6 +6,7 @@ img-ir-$(CONFIG_IR_IMG_JVC)	+= img-ir-jvc.o
 img-ir-$(CONFIG_IR_IMG_SONY)	+= img-ir-sony.o
 img-ir-$(CONFIG_IR_IMG_SHARP)	+= img-ir-sharp.o
 img-ir-$(CONFIG_IR_IMG_SANYO)	+= img-ir-sanyo.o
+img-ir-$(CONFIG_IR_IMG_RC5)	+= img-ir-rc5.o
 img-ir-objs			:= $(img-ir-y)
 
 obj-$(CONFIG_IR_IMG)		+= img-ir.o

drivers/media/rc/img-ir/img-ir-hw.c

@@ -41,6 +41,9 @@ static struct img_ir_decoder *img_ir_decoders[] = {
 #endif
 #ifdef CONFIG_IR_IMG_SANYO
 	&img_ir_sanyo,
+#endif
+#ifdef CONFIG_IR_IMG_RC5
+	&img_ir_rc5,
 #endif
 	NULL
 };

drivers/media/rc/img-ir/img-ir-hw.h

@@ -187,6 +187,7 @@ extern struct img_ir_decoder img_ir_jvc;
 extern struct img_ir_decoder img_ir_sony;
 extern struct img_ir_decoder img_ir_sharp;
 extern struct img_ir_decoder img_ir_sanyo;
+extern struct img_ir_decoder img_ir_rc5;
 
 /**
  * struct img_ir_reg_timings - Reg values for decoder timings at clock rate.

drivers/media/rc/img-ir/img-ir-rc5.c

+/*
+ * ImgTec IR Decoder setup for Philips RC-5 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 RC5 data to a scancode */
+static int img_ir_rc5_scancode(int len, u64 raw, u64 enabled_protocols,
+				struct img_ir_scancode_req *request)
+{
+	unsigned int addr, cmd, tgl, start;
+
+	/* Quirk in the decoder shifts everything by 2 to the left. */
+	raw   >>= 2;
+
+	start	=  (raw >> 13)	& 0x01;
+	tgl	=  (raw >> 11)	& 0x01;
+	addr	=  (raw >>  6)	& 0x1f;
+	cmd	=   raw		& 0x3f;
+	/*
+	 * 12th bit is used to extend the command in extended RC5 and has
+	 * no effect on standard RC5.
+	 */
+	cmd	+= ((raw >> 12) & 0x01) ? 0 : 0x40;
+
+	if (!start)
+		return -EINVAL;
+
+	request->protocol = RC_TYPE_RC5;
+	request->scancode = addr << 8 | cmd;
+	request->toggle   = tgl;
+	return IMG_IR_SCANCODE;
+}
+
+/* Convert RC5 scancode to RC5 data filter */
+static int img_ir_rc5_filter(const struct rc_scancode_filter *in,
+				 struct img_ir_filter *out, u64 protocols)
+{
+	/* Not supported by the hw. */
+	return -EINVAL;
+}
+
+/*
+ * RC-5 decoder
+ * see http://www.sbprojects.com/knowledge/ir/rc5.php
+ */
+struct img_ir_decoder img_ir_rc5 = {
+	.type      = RC_BIT_RC5,
+	.control   = {
+		.bitoriend2	= 1,
+		.code_type	= IMG_IR_CODETYPE_BIPHASE,
+		.decodend2	= 1,
+	},
+	/* main timings */
+	.tolerance	= 16,
+	.unit		= 888888, /* 1/36k*32=888.888microseconds */
+	.timings	= {
+		/* 10 symbol */
+		.s10 = {
+			.pulse	= { 1 },
+			.space	= { 1 },
+		},
+
+		/* 11 symbol */
+		.s11 = {
+			.pulse	= { 1 },
+			.space	= { 1 },
+		},
+
+		/* free time */
+		.ft  = {
+			.minlen = 14,
+			.maxlen = 14,
+			.ft_min = 5,
+		},
+	},
+
+	/* scancode logic */
+	.scancode	= img_ir_rc5_scancode,
+	.filter		= img_ir_rc5_filter,
+};