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-rw-r--r--drivers/media/IR/ir-raw-event.c251
1 files changed, 251 insertions, 0 deletions
diff --git a/drivers/media/IR/ir-raw-event.c b/drivers/media/IR/ir-raw-event.c
new file mode 100644
index 0000000..ea68a3f
--- /dev/null
+++ b/drivers/media/IR/ir-raw-event.c
@@ -0,0 +1,251 @@
+/* ir-raw-event.c - handle IR Pulse/Space event
+ *
+ * Copyright (C) 2010 by Mauro Carvalho Chehab <mchehab@redhat.com>
+ *
+ * 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 <linux/workqueue.h>
+#include <linux/spinlock.h>
+#include <linux/sched.h>
+#include "ir-core-priv.h"
+
+/* Define the max number of pulse/space transitions to buffer */
+#define MAX_IR_EVENT_SIZE 512
+
+/* Used to handle IR raw handler extensions */
+static LIST_HEAD(ir_raw_handler_list);
+static DEFINE_SPINLOCK(ir_raw_handler_lock);
+
+/**
+ * RUN_DECODER() - runs an operation on all IR decoders
+ * @ops: IR raw handler operation to be called
+ * @arg: arguments to be passed to the callback
+ *
+ * Calls ir_raw_handler::ops for all registered IR handlers. It prevents
+ * new decode addition/removal while running, by locking ir_raw_handler_lock
+ * mutex. If an error occurs, it stops the ops. Otherwise, it returns a sum
+ * of the return codes.
+ */
+#define RUN_DECODER(ops, ...) ({ \
+ struct ir_raw_handler *_ir_raw_handler; \
+ int _sumrc = 0, _rc; \
+ spin_lock(&ir_raw_handler_lock); \
+ list_for_each_entry(_ir_raw_handler, &ir_raw_handler_list, list) { \
+ if (_ir_raw_handler->ops) { \
+ _rc = _ir_raw_handler->ops(__VA_ARGS__); \
+ if (_rc < 0) \
+ break; \
+ _sumrc += _rc; \
+ } \
+ } \
+ spin_unlock(&ir_raw_handler_lock); \
+ _sumrc; \
+})
+
+#ifdef MODULE
+/* Used to load the decoders */
+static struct work_struct wq_load;
+#endif
+
+static void ir_raw_event_work(struct work_struct *work)
+{
+ struct ir_raw_event ev;
+ struct ir_raw_event_ctrl *raw =
+ container_of(work, struct ir_raw_event_ctrl, rx_work);
+
+ while (kfifo_out(&raw->kfifo, &ev, sizeof(ev)) == sizeof(ev))
+ RUN_DECODER(decode, raw->input_dev, ev);
+}
+
+int ir_raw_event_register(struct input_dev *input_dev)
+{
+ struct ir_input_dev *ir = input_get_drvdata(input_dev);
+ int rc;
+
+ ir->raw = kzalloc(sizeof(*ir->raw), GFP_KERNEL);
+ if (!ir->raw)
+ return -ENOMEM;
+
+ ir->raw->input_dev = input_dev;
+ INIT_WORK(&ir->raw->rx_work, ir_raw_event_work);
+
+ rc = kfifo_alloc(&ir->raw->kfifo, sizeof(s64) * MAX_IR_EVENT_SIZE,
+ GFP_KERNEL);
+ if (rc < 0) {
+ kfree(ir->raw);
+ ir->raw = NULL;
+ return rc;
+ }
+
+ rc = RUN_DECODER(raw_register, input_dev);
+ if (rc < 0) {
+ kfifo_free(&ir->raw->kfifo);
+ kfree(ir->raw);
+ ir->raw = NULL;
+ return rc;
+ }
+
+ return rc;
+}
+
+void ir_raw_event_unregister(struct input_dev *input_dev)
+{
+ struct ir_input_dev *ir = input_get_drvdata(input_dev);
+
+ if (!ir->raw)
+ return;
+
+ cancel_work_sync(&ir->raw->rx_work);
+ RUN_DECODER(raw_unregister, input_dev);
+
+ kfifo_free(&ir->raw->kfifo);
+ kfree(ir->raw);
+ ir->raw = NULL;
+}
+
+/**
+ * ir_raw_event_store() - pass a pulse/space duration to the raw ir decoders
+ * @input_dev: the struct input_dev device descriptor
+ * @ev: the struct ir_raw_event descriptor of the pulse/space
+ *
+ * This routine (which may be called from an interrupt context) stores a
+ * pulse/space duration for the raw ir decoding state machines. Pulses are
+ * signalled as positive values and spaces as negative values. A zero value
+ * will reset the decoding state machines.
+ */
+int ir_raw_event_store(struct input_dev *input_dev, struct ir_raw_event *ev)
+{
+ struct ir_input_dev *ir = input_get_drvdata(input_dev);
+
+ if (!ir->raw)
+ return -EINVAL;
+
+ if (kfifo_in(&ir->raw->kfifo, ev, sizeof(*ev)) != sizeof(*ev))
+ return -ENOMEM;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ir_raw_event_store);
+
+/**
+ * ir_raw_event_store_edge() - notify raw ir decoders of the start of a pulse/space
+ * @input_dev: the struct input_dev device descriptor
+ * @type: the type of the event that has occurred
+ *
+ * This routine (which may be called from an interrupt context) is used to
+ * store the beginning of an ir pulse or space (or the start/end of ir
+ * reception) for the raw ir decoding state machines. This is used by
+ * hardware which does not provide durations directly but only interrupts
+ * (or similar events) on state change.
+ */
+int ir_raw_event_store_edge(struct input_dev *input_dev, enum raw_event_type type)
+{
+ struct ir_input_dev *ir = input_get_drvdata(input_dev);
+ ktime_t now;
+ s64 delta; /* ns */
+ struct ir_raw_event ev;
+ int rc = 0;
+
+ if (!ir->raw)
+ return -EINVAL;
+
+ now = ktime_get();
+ delta = ktime_to_ns(ktime_sub(now, ir->raw->last_event));
+
+ /* Check for a long duration since last event or if we're
+ * being called for the first time, note that delta can't
+ * possibly be negative.
+ */
+ ev.duration = 0;
+ if (delta > IR_MAX_DURATION || !ir->raw->last_type)
+ type |= IR_START_EVENT;
+ else
+ ev.duration = delta;
+
+ if (type & IR_START_EVENT)
+ ir_raw_event_reset(input_dev);
+ else if (ir->raw->last_type & IR_SPACE) {
+ ev.pulse = false;
+ rc = ir_raw_event_store(input_dev, &ev);
+ } else if (ir->raw->last_type & IR_PULSE) {
+ ev.pulse = true;
+ rc = ir_raw_event_store(input_dev, &ev);
+ } else
+ return 0;
+
+ ir->raw->last_event = now;
+ ir->raw->last_type = type;
+ return rc;
+}
+EXPORT_SYMBOL_GPL(ir_raw_event_store_edge);
+
+/**
+ * ir_raw_event_handle() - schedules the decoding of stored ir data
+ * @input_dev: the struct input_dev device descriptor
+ *
+ * This routine will signal the workqueue to start decoding stored ir data.
+ */
+void ir_raw_event_handle(struct input_dev *input_dev)
+{
+ struct ir_input_dev *ir = input_get_drvdata(input_dev);
+
+ if (!ir->raw)
+ return;
+
+ schedule_work(&ir->raw->rx_work);
+}
+EXPORT_SYMBOL_GPL(ir_raw_event_handle);
+
+/*
+ * Extension interface - used to register the IR decoders
+ */
+
+int ir_raw_handler_register(struct ir_raw_handler *ir_raw_handler)
+{
+ spin_lock(&ir_raw_handler_lock);
+ list_add_tail(&ir_raw_handler->list, &ir_raw_handler_list);
+ spin_unlock(&ir_raw_handler_lock);
+ return 0;
+}
+EXPORT_SYMBOL(ir_raw_handler_register);
+
+void ir_raw_handler_unregister(struct ir_raw_handler *ir_raw_handler)
+{
+ spin_lock(&ir_raw_handler_lock);
+ list_del(&ir_raw_handler->list);
+ spin_unlock(&ir_raw_handler_lock);
+}
+EXPORT_SYMBOL(ir_raw_handler_unregister);
+
+#ifdef MODULE
+static void init_decoders(struct work_struct *work)
+{
+ /* Load the decoder modules */
+
+ load_nec_decode();
+ load_rc5_decode();
+ load_rc6_decode();
+ load_jvc_decode();
+ load_sony_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
+ */
+}
+#endif
+
+void ir_raw_init(void)
+{
+#ifdef MODULE
+ INIT_WORK(&wq_load, init_decoders);
+ schedule_work(&wq_load);
+#endif
+}