V4L/DVB: Add RC5x support to ir-core

This patch adds RC5x support to drivers/media/IR/ir-rc5-decoder.c

Signed-off-by: David Härdeman <david@hardeman.nu>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/IR/ir-rc5-decoder.c b/drivers/media/IR/ir-rc5-decoder.c
index d8f0760..dd5a4d5 100644 (file)
--- a/drivers/media/IR/ir-rc5-decoder.c
+++ b/drivers/media/IR/ir-rc5-decoder.c
@@ -1,4 +1,4 @@
-/* ir-rc5-decoder.c - handle RC-5 IR Pulse/Space protocol
+/* ir-rc5-decoder.c - handle RC5(x) IR Pulse/Space protocol
  *
  * Copyright (C) 2010 by Mauro Carvalho Chehab <mchehab@redhat.com>
  *
@@ -13,15 +13,19 @@
  */
 
 /*
- * This code only handles 14 bits RC-5 protocols. There are other variants
- * that use a different number of bits. This is currently unsupported
- * It considers a carrier of 36 kHz, with a total of 14 bits, where
+ * This code handles 14 bits RC5 protocols and 20 bits RC5x protocols.
+ * There are other variants that use a different number of bits.
+ * This is currently unsupported.
+ * It considers a carrier of 36 kHz, with a total of 14/20 bits, where
  * the first two bits are start bits, and a third one is a filing bit
  */
 
 #include "ir-core-priv.h"
 
 #define RC5_NBITS              14
+#define RC5X_NBITS             20
+#define CHECK_RC5X_NBITS       8
+#define RC5X_SPACE             SPACE(4)
 #define RC5_UNIT               888888 /* ns */
 
 /* Used to register rc5_decoder clients */
@@ -32,6 +36,7 @@ enum rc5_state {
        STATE_INACTIVE,
        STATE_BIT_START,
        STATE_BIT_END,
+       STATE_CHECK_RC5X,
        STATE_FINISHED,
 };
 
@@ -45,6 +50,7 @@ struct decoder_data {
        u32                     rc5_bits;
        int                     last_unit;
        unsigned                count;
+       unsigned                wanted_bits;
 };
 
 
@@ -126,7 +132,7 @@ static int ir_rc5_decode(struct input_dev *input_dev, s64 duration)
 {
        struct decoder_data *data;
        struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
-       u8 command, system, toggle;
+       u8 toggle;
        u32 scancode;
        int u;
 
@@ -147,7 +153,7 @@ static int ir_rc5_decode(struct input_dev *input_dev, s64 duration)
                goto out;
 
 again:
-       IR_dprintk(2, "RC5 decode started at state %i (%i units, %ius)\n",
+       IR_dprintk(2, "RC5(x) decode started at state %i (%i units, %ius)\n",
                   data->state, u, TO_US(duration));
 
        if (DURATION(u) == 0 && data->state != STATE_FINISHED)
@@ -159,6 +165,8 @@ again:
                if (IS_PULSE(u)) {
                        data->state = STATE_BIT_START;
                        data->count = 1;
+                       /* We just need enough bits to get to STATE_CHECK_RC5X */
+                       data->wanted_bits = RC5X_NBITS;
                        DECREASE_DURATION(u, 1);
                        goto again;
                }
@@ -176,7 +184,7 @@ again:
                         * If the last bit is zero, a space will merge
                         * with the silence after the command.
                         */
-                       if (IS_PULSE(u) && data->count == RC5_NBITS) {
+                       if (IS_PULSE(u) && data->count == data->wanted_bits) {
                                data->state = STATE_FINISHED;
                                goto again;
                        }
@@ -188,8 +196,10 @@ again:
 
        case STATE_BIT_END:
                if (IS_TRANSITION(u, data->last_unit)) {
-                       if (data->count == RC5_NBITS)
+                       if (data->count == data->wanted_bits)
                                data->state = STATE_FINISHED;
+                       else if (data->count == CHECK_RC5X_NBITS)
+                               data->state = STATE_CHECK_RC5X;
                        else
                                data->state = STATE_BIT_START;
 
@@ -198,22 +208,52 @@ again:
                }
                break;
 
+       case STATE_CHECK_RC5X:
+               if (IS_SPACE(u) && DURATION(u) >= DURATION(RC5X_SPACE)) {
+                       /* RC5X */
+                       data->wanted_bits = RC5X_NBITS;
+                       DECREASE_DURATION(u, DURATION(RC5X_SPACE));
+               } else {
+                       /* RC5 */
+                       data->wanted_bits = RC5_NBITS;
+               }
+               data->state = STATE_BIT_START;
+               goto again;
+
        case STATE_FINISHED:
-               command  = (data->rc5_bits & 0x0003F) >> 0;
-               system   = (data->rc5_bits & 0x007C0) >> 6;
-               toggle   = (data->rc5_bits & 0x00800) ? 1 : 0;
-               command += (data->rc5_bits & 0x01000) ? 0 : 0x40;
-               scancode = system << 8 | command;
-
-               IR_dprintk(1, "RC5 scancode 0x%04x (toggle: %u)\n",
-                          scancode, toggle);
+               if (data->wanted_bits == RC5X_NBITS) {
+                       /* RC5X */
+                       u8 xdata, command, system;
+                       xdata    = (data->rc5_bits & 0x0003F) >> 0;
+                       command  = (data->rc5_bits & 0x00FC0) >> 6;
+                       system   = (data->rc5_bits & 0x1F000) >> 12;
+                       toggle   = (data->rc5_bits & 0x20000) ? 1 : 0;
+                       command += (data->rc5_bits & 0x01000) ? 0 : 0x40;
+                       scancode = system << 16 | command << 8 | xdata;
+
+                       IR_dprintk(1, "RC5X scancode 0x%06x (toggle: %u)\n",
+                                  scancode, toggle);
+
+               } else {
+                       /* RC5 */
+                       u8 command, system;
+                       command  = (data->rc5_bits & 0x0003F) >> 0;
+                       system   = (data->rc5_bits & 0x007C0) >> 6;
+                       toggle   = (data->rc5_bits & 0x00800) ? 1 : 0;
+                       command += (data->rc5_bits & 0x01000) ? 0 : 0x40;
+                       scancode = system << 8 | command;
+
+                       IR_dprintk(1, "RC5 scancode 0x%04x (toggle: %u)\n",
+                                  scancode, toggle);
+               }
+
                ir_keydown(input_dev, scancode, toggle);
                data->state = STATE_INACTIVE;
                return 0;
        }
 
 out:
-       IR_dprintk(1, "RC5 decode failed at state %i (%i units, %ius)\n",
+       IR_dprintk(1, "RC5(x) decode failed at state %i (%i units, %ius)\n",
                   data->state, u, TO_US(duration));
        data->state = STATE_INACTIVE;
        return -EINVAL;
@@ -273,7 +313,7 @@ static int __init ir_rc5_decode_init(void)
 {
        ir_raw_handler_register(&rc5_handler);
 
-       printk(KERN_INFO "IR RC-5 protocol handler initialized\n");
+       printk(KERN_INFO "IR RC5(x) protocol handler initialized\n");
        return 0;
 }
 
@@ -288,4 +328,4 @@ module_exit(ir_rc5_decode_exit);
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>");
 MODULE_AUTHOR("Red Hat Inc. (http://www.redhat.com)");
-MODULE_DESCRIPTION("RC-5 IR protocol decoder");
+MODULE_DESCRIPTION("RC5(x) IR protocol decoder");