diff options
Diffstat (limited to 'drivers/media/IR/ir-raw-event.c')
| -rw-r--r-- | drivers/media/IR/ir-raw-event.c | 251 |
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 000000000000..ea68a3f2effa --- /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 +} |