V4L/DVB: Add RC6 support to ir-core
authorDavid Härdeman <david@hardeman.nu>
Thu, 8 Apr 2010 23:04:40 +0000 (20:04 -0300)
committerMauro Carvalho Chehab <mchehab@redhat.com>
Wed, 19 May 2010 15:57:17 +0000 (12:57 -0300)
This patch adds an RC6 decoder (modes 0 and 6A) to ir-core.

Signed-off-by: David Härdeman <david@hardeman.nu>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
drivers/media/IR/Kconfig
drivers/media/IR/Makefile
drivers/media/IR/ir-core-priv.h
drivers/media/IR/ir-raw-event.c
drivers/media/IR/ir-rc6-decoder.c [new file with mode: 0644]
drivers/media/IR/ir-sysfs.c
include/media/rc-map.h

index ba81bda3513d27e98068569765f1a68869e783ee..28d336d981872beb3b286e1117621eec8447c9a4 100644 (file)
@@ -27,3 +27,12 @@ config IR_RC5_DECODER
        ---help---
           Enable this option if you have IR with RC-5 protocol, and
           if the IR is decoded in software
+
+config IR_RC6_DECODER
+       tristate "Enable IR raw decoder for the RC6 protocol"
+       depends on IR_CORE
+       default y
+
+       ---help---
+          Enable this option if you have an infrared remote control which
+          uses the RC6 protocol, and you need software decoding support.
index 62e12d5c443aefd29cccb14726b1174c9a8a78f1..792d9cad7efc12eda3ec1b4bb16bf888725417bc 100644 (file)
@@ -7,3 +7,4 @@ obj-$(CONFIG_IR_CORE) += ir-core.o
 obj-$(CONFIG_VIDEO_IR) += ir-common.o
 obj-$(CONFIG_IR_NEC_DECODER) += ir-nec-decoder.o
 obj-$(CONFIG_IR_RC5_DECODER) += ir-rc5-decoder.o
+obj-$(CONFIG_IR_RC6_DECODER) += ir-rc6-decoder.o
index ea546659e4ce04bc637cefa6c835780bbcdca490..59d5ed7e103e9653e20f423eda657337994bada2 100644 (file)
@@ -108,4 +108,11 @@ void ir_raw_init(void);
 #define load_rc5_decode()      0
 #endif
 
+/* from ir-rc6-decoder.c */
+#ifdef CONFIG_IR_RC5_DECODER_MODULE
+#define load_rc6_decode()      request_module("ir-rc6-decoder")
+#else
+#define load_rc6_decode()      0
+#endif
+
 #endif /* _IR_RAW_EVENT */
index b49d01256be3f10d414a9e8d6c1f481b03ecb74a..674442b2f0a879d4b2b717f7f5fa4f5ef2376358 100644 (file)
@@ -226,6 +226,7 @@ static void init_decoders(struct work_struct *work)
 
        load_nec_decode();
        load_rc5_decode();
+       load_rc6_decode();
 
        /* If needed, we may later add some init code. In this case,
           it is needed to change the CONFIG_MODULE test at ir-core.h
diff --git a/drivers/media/IR/ir-rc6-decoder.c b/drivers/media/IR/ir-rc6-decoder.c
new file mode 100644 (file)
index 0000000..ccc5be2
--- /dev/null
@@ -0,0 +1,412 @@
+/* ir-rc6-decoder.c - A decoder for the RC6 IR protocol
+ *
+ * Copyright (C) 2010 by David Härdeman <david@hardeman.nu>
+ *
+ * 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 version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include "ir-core-priv.h"
+
+/*
+ * This decoder currently supports:
+ * RC6-0-16    (standard toggle bit in header)
+ * RC6-6A-24   (no toggle bit)
+ * RC6-6A-32   (MCE version with toggle bit in body)
+ */
+
+#define RC6_UNIT               444444  /* us */
+#define RC6_HEADER_NBITS       4       /* not including toggle bit */
+#define RC6_0_NBITS            16
+#define RC6_6A_SMALL_NBITS     24
+#define RC6_6A_LARGE_NBITS     32
+#define RC6_PREFIX_PULSE       PULSE(6)
+#define RC6_PREFIX_SPACE       SPACE(2)
+#define RC6_MODE_MASK          0x07    /* for the header bits */
+#define RC6_STARTBIT_MASK      0x08    /* for the header bits */
+#define RC6_6A_MCE_TOGGLE_MASK 0x8000  /* for the body bits */
+
+/* Used to register rc6_decoder clients */
+static LIST_HEAD(decoder_list);
+static DEFINE_SPINLOCK(decoder_lock);
+
+enum rc6_mode {
+       RC6_MODE_0,
+       RC6_MODE_6A,
+       RC6_MODE_UNKNOWN,
+};
+
+enum rc6_state {
+       STATE_INACTIVE,
+       STATE_PREFIX_SPACE,
+       STATE_HEADER_BIT_START,
+       STATE_HEADER_BIT_END,
+       STATE_TOGGLE_START,
+       STATE_TOGGLE_END,
+       STATE_BODY_BIT_START,
+       STATE_BODY_BIT_END,
+       STATE_FINISHED,
+};
+
+struct decoder_data {
+       struct list_head        list;
+       struct ir_input_dev     *ir_dev;
+       int                     enabled:1;
+
+       /* State machine control */
+       enum rc6_state          state;
+       u8                      header;
+       u32                     body;
+       int                     last_unit;
+       bool                    toggle;
+       unsigned                count;
+       unsigned                wanted_bits;
+};
+
+
+/**
+ * get_decoder_data()  - gets decoder data
+ * @input_dev: input device
+ *
+ * Returns the struct decoder_data that corresponds to a device
+ */
+static struct decoder_data *get_decoder_data(struct  ir_input_dev *ir_dev)
+{
+       struct decoder_data *data = NULL;
+
+       spin_lock(&decoder_lock);
+       list_for_each_entry(data, &decoder_list, list) {
+               if (data->ir_dev == ir_dev)
+                       break;
+       }
+       spin_unlock(&decoder_lock);
+       return data;
+}
+
+static ssize_t store_enabled(struct device *d,
+                            struct device_attribute *mattr,
+                            const char *buf,
+                            size_t len)
+{
+       unsigned long value;
+       struct ir_input_dev *ir_dev = dev_get_drvdata(d);
+       struct decoder_data *data = get_decoder_data(ir_dev);
+
+       if (!data)
+               return -EINVAL;
+
+       if (strict_strtoul(buf, 10, &value) || value > 1)
+               return -EINVAL;
+
+       data->enabled = value;
+
+       return len;
+}
+
+static ssize_t show_enabled(struct device *d,
+                            struct device_attribute *mattr, char *buf)
+{
+       struct ir_input_dev *ir_dev = dev_get_drvdata(d);
+       struct decoder_data *data = get_decoder_data(ir_dev);
+
+       if (!data)
+               return -EINVAL;
+
+       if (data->enabled)
+               return sprintf(buf, "1\n");
+       else
+       return sprintf(buf, "0\n");
+}
+
+static DEVICE_ATTR(enabled, S_IRUGO | S_IWUSR, show_enabled, store_enabled);
+
+static struct attribute *decoder_attributes[] = {
+       &dev_attr_enabled.attr,
+       NULL
+};
+
+static struct attribute_group decoder_attribute_group = {
+       .name   = "rc6_decoder",
+       .attrs  = decoder_attributes,
+};
+
+static enum rc6_mode rc6_mode(struct decoder_data *data) {
+       switch (data->header & RC6_MODE_MASK) {
+       case 0:
+               return RC6_MODE_0;
+       case 6:
+               if (!data->toggle)
+                       return RC6_MODE_6A;
+               /* fall through */
+       default:
+               return RC6_MODE_UNKNOWN;
+       }
+}
+
+/**
+ * ir_rc6_decode() - Decode one RC6 pulse or space
+ * @input_dev: the struct input_dev descriptor of the device
+ * @duration:  duration of pulse/space in ns
+ *
+ * This function returns -EINVAL if the pulse violates the state machine
+ */
+static int ir_rc6_decode(struct input_dev *input_dev, s64 duration)
+{
+       struct decoder_data *data;
+       struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
+       u32 scancode;
+       u8 toggle;
+       int u;
+
+       data = get_decoder_data(ir_dev);
+       if (!data)
+               return -EINVAL;
+
+       if (!data->enabled)
+               return 0;
+
+       if (IS_RESET(duration)) {
+               data->state = STATE_INACTIVE;
+               return 0;
+       }
+
+       u =  TO_UNITS(duration, RC6_UNIT);
+       if (DURATION(u) == 0)
+               goto out;
+
+again:
+       IR_dprintk(2, "RC6 decode started at state %i (%i units, %ius)\n",
+                  data->state, u, TO_US(duration));
+
+       if (DURATION(u) == 0 && data->state != STATE_FINISHED)
+               return 0;
+
+       switch (data->state) {
+
+       case STATE_INACTIVE:
+               if (u >= RC6_PREFIX_PULSE - 1 && u <= RC6_PREFIX_PULSE + 1) {
+                       data->state = STATE_PREFIX_SPACE;
+                       data->count = 0;
+                       return 0;
+               }
+               break;
+
+       case STATE_PREFIX_SPACE:
+               if (u == RC6_PREFIX_SPACE) {
+                       data->state = STATE_HEADER_BIT_START;
+                       return 0;
+               }
+               break;
+
+       case STATE_HEADER_BIT_START:
+               if (DURATION(u) == 1) {
+                       data->header <<= 1;
+                       if (IS_PULSE(u))
+                               data->header |= 1;
+                       data->count++;
+                       data->last_unit = u;
+                       data->state = STATE_HEADER_BIT_END;
+                       return 0;
+               }
+               break;
+
+       case STATE_HEADER_BIT_END:
+               if (IS_TRANSITION(u, data->last_unit)) {
+                       if (data->count == RC6_HEADER_NBITS)
+                               data->state = STATE_TOGGLE_START;
+                       else
+                               data->state = STATE_HEADER_BIT_START;
+
+                       DECREASE_DURATION(u, 1);
+                       goto again;
+               }
+               break;
+
+       case STATE_TOGGLE_START:
+               if (DURATION(u) == 2) {
+                       data->toggle = IS_PULSE(u);
+                       data->last_unit = u;
+                       data->state = STATE_TOGGLE_END;
+                       return 0;
+               }
+               break;
+
+       case STATE_TOGGLE_END:
+               if (IS_TRANSITION(u, data->last_unit) && DURATION(u) >= 2) {
+                       data->state = STATE_BODY_BIT_START;
+                       data->last_unit = u;
+                       DECREASE_DURATION(u, 2);
+                       data->count = 0;
+
+                       if (!(data->header & RC6_STARTBIT_MASK)) {
+                               IR_dprintk(1, "RC6 invalid start bit\n");
+                               break;
+                       }
+
+                       switch (rc6_mode(data)) {
+                       case RC6_MODE_0:
+                               data->wanted_bits = RC6_0_NBITS;
+                               break;
+                       case RC6_MODE_6A:
+                               /* This might look weird, but we basically
+                                  check the value of the first body bit to
+                                  determine the number of bits in mode 6A */
+                               if ((DURATION(u) == 0 && IS_SPACE(data->last_unit)) || DURATION(u) > 0)
+                                       data->wanted_bits = RC6_6A_LARGE_NBITS;
+                               else
+                                       data->wanted_bits = RC6_6A_SMALL_NBITS;
+                               break;
+                       default:
+                               IR_dprintk(1, "RC6 unknown mode\n");
+                               goto out;
+                       }
+                       goto again;
+               }
+               break;
+
+       case STATE_BODY_BIT_START:
+               if (DURATION(u) == 1) {
+                       data->body <<= 1;
+                       if (IS_PULSE(u))
+                               data->body |= 1;
+                       data->count++;
+                       data->last_unit = u;
+
+                       /*
+                        * If the last bit is one, a space will merge
+                        * with the silence after the command.
+                        */
+                       if (IS_PULSE(u) && data->count == data->wanted_bits) {
+                               data->state = STATE_FINISHED;
+                               goto again;
+                       }
+
+                       data->state = STATE_BODY_BIT_END;
+                       return 0;
+               }
+               break;
+
+       case STATE_BODY_BIT_END:
+               if (IS_TRANSITION(u, data->last_unit)) {
+                       if (data->count == data->wanted_bits)
+                               data->state = STATE_FINISHED;
+                       else
+                               data->state = STATE_BODY_BIT_START;
+
+                       DECREASE_DURATION(u, 1);
+                       goto again;
+               }
+               break;
+
+       case STATE_FINISHED:
+               switch (rc6_mode(data)) {
+               case RC6_MODE_0:
+                       scancode = data->body & 0xffff;
+                       toggle = data->toggle;
+                       IR_dprintk(1, "RC6(0) scancode 0x%04x (toggle: %u)\n",
+                                  scancode, toggle);
+                       break;
+               case RC6_MODE_6A:
+                       if (data->wanted_bits == RC6_6A_LARGE_NBITS) {
+                               toggle = data->body & RC6_6A_MCE_TOGGLE_MASK ? 1 : 0;
+                               scancode = data->body & ~RC6_6A_MCE_TOGGLE_MASK;
+                       } else {
+                               toggle = 0;
+                               scancode = data->body & 0xffffff;
+                       }
+
+                       IR_dprintk(1, "RC6(6A) scancode 0x%08x (toggle: %u)\n",
+                                  scancode, toggle);
+                       break;
+               default:
+                       IR_dprintk(1, "RC6 unknown mode\n");
+                       goto out;
+               }
+
+               ir_keydown(input_dev, scancode, toggle);
+               data->state = STATE_INACTIVE;
+               return 0;
+       }
+
+out:
+       IR_dprintk(1, "RC6 decode failed at state %i (%i units, %ius)\n",
+                  data->state, u, TO_US(duration));
+       data->state = STATE_INACTIVE;
+       return -EINVAL;
+}
+
+static int ir_rc6_register(struct input_dev *input_dev)
+{
+       struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
+       struct decoder_data *data;
+       int rc;
+
+       rc = sysfs_create_group(&ir_dev->dev.kobj, &decoder_attribute_group);
+       if (rc < 0)
+               return rc;
+
+       data = kzalloc(sizeof(*data), GFP_KERNEL);
+       if (!data) {
+               sysfs_remove_group(&ir_dev->dev.kobj, &decoder_attribute_group);
+               return -ENOMEM;
+       }
+
+       data->ir_dev = ir_dev;
+       data->enabled = 1;
+
+       spin_lock(&decoder_lock);
+       list_add_tail(&data->list, &decoder_list);
+       spin_unlock(&decoder_lock);
+
+       return 0;
+}
+
+static int ir_rc6_unregister(struct input_dev *input_dev)
+{
+       struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
+       static struct decoder_data *data;
+
+       data = get_decoder_data(ir_dev);
+       if (!data)
+               return 0;
+
+       sysfs_remove_group(&ir_dev->dev.kobj, &decoder_attribute_group);
+
+       spin_lock(&decoder_lock);
+       list_del(&data->list);
+       spin_unlock(&decoder_lock);
+
+       return 0;
+}
+
+static struct ir_raw_handler rc6_handler = {
+       .decode         = ir_rc6_decode,
+       .raw_register   = ir_rc6_register,
+       .raw_unregister = ir_rc6_unregister,
+};
+
+static int __init ir_rc6_decode_init(void)
+{
+       ir_raw_handler_register(&rc6_handler);
+
+       printk(KERN_INFO "IR RC6 protocol handler initialized\n");
+       return 0;
+}
+
+static void __exit ir_rc6_decode_exit(void)
+{
+       ir_raw_handler_unregister(&rc6_handler);
+}
+
+module_init(ir_rc6_decode_init);
+module_exit(ir_rc6_decode_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("David Härdeman <david@hardeman.nu>");
+MODULE_DESCRIPTION("RC6 IR protocol decoder");
index 57f09c4ca9fb903c9e973204b55e27e89ec86384..073b5c0dc654d92af52ff7dc8ec53eabc3596b9c 100644 (file)
@@ -61,6 +61,8 @@ static ssize_t show_protocol(struct device *d,
                s = "pulse-distance";
        else if (ir_type == IR_TYPE_NEC)
                s = "nec";
+       else if (ir_type == IR_TYPE_RC6)
+               s = "rc6";
        else
                s = "other";
 
index 3b7fe5a0dc72cc14dd4b9374d6fd161c610fad23..11f66182b91fc9a2ab1c9d6798d382025e7f1e31 100644 (file)
@@ -15,6 +15,7 @@
 #define IR_TYPE_RC5    (1  << 0)       /* Philips RC5 protocol */
 #define IR_TYPE_PD     (1  << 1)       /* Pulse distance encoded IR */
 #define IR_TYPE_NEC    (1  << 2)
+#define IR_TYPE_RC6    (1  << 3)       /* Philips RC6 protocol */
 #define IR_TYPE_OTHER  (1u << 31)
 
 struct ir_scancode {