diff options
Diffstat (limited to 'drivers/media/rc/ir-raw.c')
-rw-r--r-- | drivers/media/rc/ir-raw.c | 371 |
1 files changed, 371 insertions, 0 deletions
diff --git a/drivers/media/rc/ir-raw.c b/drivers/media/rc/ir-raw.c new file mode 100644 index 000000000000..73230ff93b8a --- /dev/null +++ b/drivers/media/rc/ir-raw.c @@ -0,0 +1,371 @@ +/* ir-raw.c - handle IR pulse/space events + * + * 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/kthread.h> +#include <linux/mutex.h> +#include <linux/sched.h> +#include <linux/freezer.h> +#include "rc-core-priv.h" + +/* Define the max number of pulse/space transitions to buffer */ +#define MAX_IR_EVENT_SIZE 512 + +/* Used to keep track of IR raw clients, protected by ir_raw_handler_lock */ +static LIST_HEAD(ir_raw_client_list); + +/* Used to handle IR raw handler extensions */ +static DEFINE_MUTEX(ir_raw_handler_lock); +static LIST_HEAD(ir_raw_handler_list); +static u64 available_protocols; + +#ifdef MODULE +/* Used to load the decoders */ +static struct work_struct wq_load; +#endif + +static int ir_raw_event_thread(void *data) +{ + struct ir_raw_event ev; + struct ir_raw_handler *handler; + struct ir_raw_event_ctrl *raw = (struct ir_raw_event_ctrl *)data; + int retval; + + while (!kthread_should_stop()) { + + spin_lock_irq(&raw->lock); + retval = kfifo_out(&raw->kfifo, &ev, sizeof(ev)); + + if (!retval) { + set_current_state(TASK_INTERRUPTIBLE); + + if (kthread_should_stop()) + set_current_state(TASK_RUNNING); + + spin_unlock_irq(&raw->lock); + schedule(); + continue; + } + + spin_unlock_irq(&raw->lock); + + + BUG_ON(retval != sizeof(ev)); + + mutex_lock(&ir_raw_handler_lock); + list_for_each_entry(handler, &ir_raw_handler_list, list) + handler->decode(raw->dev, ev); + raw->prev_ev = ev; + mutex_unlock(&ir_raw_handler_lock); + } + + return 0; +} + +/** + * ir_raw_event_store() - pass a pulse/space duration to the raw ir decoders + * @dev: the struct rc_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 rc_dev *dev, struct ir_raw_event *ev) +{ + if (!dev->raw) + return -EINVAL; + + IR_dprintk(2, "sample: (%05dus %s)\n", + TO_US(ev->duration), TO_STR(ev->pulse)); + + if (kfifo_in(&dev->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 + * @dev: the struct rc_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 rc_dev *dev, enum raw_event_type type) +{ + ktime_t now; + s64 delta; /* ns */ + struct ir_raw_event ev; + int rc = 0; + + if (!dev->raw) + return -EINVAL; + + now = ktime_get(); + delta = ktime_to_ns(ktime_sub(now, dev->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 || !dev->raw->last_type) + type |= IR_START_EVENT; + else + ev.duration = delta; + + if (type & IR_START_EVENT) + ir_raw_event_reset(dev); + else if (dev->raw->last_type & IR_SPACE) { + ev.pulse = false; + rc = ir_raw_event_store(dev, &ev); + } else if (dev->raw->last_type & IR_PULSE) { + ev.pulse = true; + rc = ir_raw_event_store(dev, &ev); + } else + return 0; + + dev->raw->last_event = now; + dev->raw->last_type = type; + return rc; +} +EXPORT_SYMBOL_GPL(ir_raw_event_store_edge); + +/** + * ir_raw_event_store_with_filter() - pass next pulse/space to decoders with some processing + * @dev: the struct rc_dev device descriptor + * @type: the type of the event that has occurred + * + * This routine (which may be called from an interrupt context) works + * in similiar manner to ir_raw_event_store_edge. + * This routine is intended for devices with limited internal buffer + * It automerges samples of same type, and handles timeouts + */ +int ir_raw_event_store_with_filter(struct rc_dev *dev, struct ir_raw_event *ev) +{ + if (!dev->raw) + return -EINVAL; + + /* Ignore spaces in idle mode */ + if (dev->idle && !ev->pulse) + return 0; + else if (dev->idle) + ir_raw_event_set_idle(dev, false); + + if (!dev->raw->this_ev.duration) + dev->raw->this_ev = *ev; + else if (ev->pulse == dev->raw->this_ev.pulse) + dev->raw->this_ev.duration += ev->duration; + else { + ir_raw_event_store(dev, &dev->raw->this_ev); + dev->raw->this_ev = *ev; + } + + /* Enter idle mode if nessesary */ + if (!ev->pulse && dev->timeout && + dev->raw->this_ev.duration >= dev->timeout) + ir_raw_event_set_idle(dev, true); + + return 0; +} +EXPORT_SYMBOL_GPL(ir_raw_event_store_with_filter); + +/** + * ir_raw_event_set_idle() - provide hint to rc-core when the device is idle or not + * @dev: the struct rc_dev device descriptor + * @idle: whether the device is idle or not + */ +void ir_raw_event_set_idle(struct rc_dev *dev, bool idle) +{ + if (!dev->raw) + return; + + IR_dprintk(2, "%s idle mode\n", idle ? "enter" : "leave"); + + if (idle) { + dev->raw->this_ev.timeout = true; + ir_raw_event_store(dev, &dev->raw->this_ev); + init_ir_raw_event(&dev->raw->this_ev); + } + + if (dev->s_idle) + dev->s_idle(dev, idle); + + dev->idle = idle; +} +EXPORT_SYMBOL_GPL(ir_raw_event_set_idle); + +/** + * ir_raw_event_handle() - schedules the decoding of stored ir data + * @dev: the struct rc_dev device descriptor + * + * This routine will tell rc-core to start decoding stored ir data. + */ +void ir_raw_event_handle(struct rc_dev *dev) +{ + unsigned long flags; + + if (!dev->raw) + return; + + spin_lock_irqsave(&dev->raw->lock, flags); + wake_up_process(dev->raw->thread); + spin_unlock_irqrestore(&dev->raw->lock, flags); +} +EXPORT_SYMBOL_GPL(ir_raw_event_handle); + +/* used internally by the sysfs interface */ +u64 +ir_raw_get_allowed_protocols(void) +{ + u64 protocols; + mutex_lock(&ir_raw_handler_lock); + protocols = available_protocols; + mutex_unlock(&ir_raw_handler_lock); + return protocols; +} + +/* + * Used to (un)register raw event clients + */ +int ir_raw_event_register(struct rc_dev *dev) +{ + int rc; + struct ir_raw_handler *handler; + + if (!dev) + return -EINVAL; + + dev->raw = kzalloc(sizeof(*dev->raw), GFP_KERNEL); + if (!dev->raw) + return -ENOMEM; + + dev->raw->dev = dev; + dev->raw->enabled_protocols = ~0; + rc = kfifo_alloc(&dev->raw->kfifo, + sizeof(struct ir_raw_event) * MAX_IR_EVENT_SIZE, + GFP_KERNEL); + if (rc < 0) + goto out; + + spin_lock_init(&dev->raw->lock); + dev->raw->thread = kthread_run(ir_raw_event_thread, dev->raw, + "rc%ld", dev->devno); + + if (IS_ERR(dev->raw->thread)) { + rc = PTR_ERR(dev->raw->thread); + goto out; + } + + mutex_lock(&ir_raw_handler_lock); + list_add_tail(&dev->raw->list, &ir_raw_client_list); + list_for_each_entry(handler, &ir_raw_handler_list, list) + if (handler->raw_register) + handler->raw_register(dev); + mutex_unlock(&ir_raw_handler_lock); + + return 0; + +out: + kfree(dev->raw); + dev->raw = NULL; + return rc; +} + +void ir_raw_event_unregister(struct rc_dev *dev) +{ + struct ir_raw_handler *handler; + + if (!dev || !dev->raw) + return; + + kthread_stop(dev->raw->thread); + + mutex_lock(&ir_raw_handler_lock); + list_del(&dev->raw->list); + list_for_each_entry(handler, &ir_raw_handler_list, list) + if (handler->raw_unregister) + handler->raw_unregister(dev); + mutex_unlock(&ir_raw_handler_lock); + + kfifo_free(&dev->raw->kfifo); + kfree(dev->raw); + dev->raw = NULL; +} + +/* + * Extension interface - used to register the IR decoders + */ + +int ir_raw_handler_register(struct ir_raw_handler *ir_raw_handler) +{ + struct ir_raw_event_ctrl *raw; + + mutex_lock(&ir_raw_handler_lock); + list_add_tail(&ir_raw_handler->list, &ir_raw_handler_list); + if (ir_raw_handler->raw_register) + list_for_each_entry(raw, &ir_raw_client_list, list) + ir_raw_handler->raw_register(raw->dev); + available_protocols |= ir_raw_handler->protocols; + mutex_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) +{ + struct ir_raw_event_ctrl *raw; + + mutex_lock(&ir_raw_handler_lock); + list_del(&ir_raw_handler->list); + if (ir_raw_handler->raw_unregister) + list_for_each_entry(raw, &ir_raw_client_list, list) + ir_raw_handler->raw_unregister(raw->dev); + available_protocols &= ~ir_raw_handler->protocols; + mutex_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(); + load_lirc_codec(); + + /* If needed, we may later add some init code. In this case, + it is needed to change the CONFIG_MODULE test at rc-core.h + */ +} +#endif + +void ir_raw_init(void) +{ +#ifdef MODULE + INIT_WORK(&wq_load, init_decoders); + schedule_work(&wq_load); +#endif +} |