V4L/DVB: ir-core: Add logic to decode IR protocols at the IR core

Adds a method to pass IR raw pulse/code events into ir-core. This is
needed in order to support LIRC. It also helps to move common code
from the drivers into the core.

In order to allow testing, it implements a simple NEC protocol decoder
at ir-nec-decoder.c file. The logic is about the same used at saa7134
driver that handles Avermedia M135A and Encore FM53 boards.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Mauro Carvalho Chehab 2010-03-20 20:59:44 -03:00
parent 0210894956
commit a3572c34da
6 changed files with 365 additions and 5 deletions

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@ -1,5 +1,5 @@
ir-common-objs := ir-functions.o ir-keymaps.o
ir-core-objs := ir-keytable.o ir-sysfs.o
ir-core-objs := ir-keytable.o ir-sysfs.o ir-raw-event.o ir-nec-decoder.o
obj-$(CONFIG_IR_CORE) += ir-core.o
obj-$(CONFIG_VIDEO_IR) += ir-common.o

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@ -0,0 +1,131 @@
/* 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 <media/ir-core.h>
/* Start time: 4.5 ms */
#define MIN_START_TIME 3900000
#define MAX_START_TIME 5100000
/* Pulse time: 560 us */
#define MIN_PULSE_TIME 460000
#define MAX_PULSE_TIME 660000
/* Bit 1 space time: 2.25ms-560 us */
#define MIN_BIT1_TIME 1490000
#define MAX_BIT1_TIME 1890000
/* Bit 0 space time: 1.12ms-560 us */
#define MIN_BIT0_TIME 360000
#define MAX_BIT0_TIME 760000
/** Decode NEC pulsecode. This code can take up to 76.5 ms to run.
Unfortunately, using IRQ to decode pulse didn't work, since it uses
a pulse train of 38KHz. This means one pulse on each 52 us
*/
int ir_nec_decode(struct input_dev *input_dev,
struct ir_raw_event *evs,
int len)
{
int i, count = -1;
int ircode = 0, not_code = 0;
#if 0
/* Needed only after porting the event code to the decoder */
struct ir_input_dev *ir = input_get_drvdata(input_dev);
#endif
/* Be sure that the first event is an start one and is a pulse */
for (i = 0; i < len; i++) {
if (evs[i].type & (IR_START_EVENT | IR_PULSE))
break;
}
i++; /* First event doesn't contain data */
if (i >= len)
return 0;
/* First space should have 4.5 ms otherwise is not NEC protocol */
if ((evs[i].delta.tv_nsec < MIN_START_TIME) |
(evs[i].delta.tv_nsec > MAX_START_TIME) |
(evs[i].type != IR_SPACE))
goto err;
/*
* FIXME: need to implement the repeat sequence
*/
count = 0;
for (i++; i < len; i++) {
int bit;
if ((evs[i].delta.tv_nsec < MIN_PULSE_TIME) |
(evs[i].delta.tv_nsec > MAX_PULSE_TIME) |
(evs[i].type != IR_PULSE))
goto err;
if (++i >= len)
goto err;
if (evs[i].type != IR_SPACE)
goto err;
if ((evs[i].delta.tv_nsec > MIN_BIT1_TIME) &&
(evs[i].delta.tv_nsec < MAX_BIT1_TIME))
bit = 1;
else if ((evs[i].delta.tv_nsec > MIN_BIT0_TIME) &&
(evs[i].delta.tv_nsec < MAX_BIT0_TIME))
bit = 0;
else
goto err;
if (bit) {
int shift = count;
/* Address first, then command */
if (shift < 8) {
shift += 8;
ircode |= 1 << shift;
} else if (shift < 16) {
not_code |= 1 << shift;
} else if (shift < 24) {
shift -= 16;
ircode |= 1 << shift;
} else {
shift -= 24;
not_code |= 1 << shift;
}
}
if (++count == 32)
break;
}
/*
* Fixme: may need to accept Extended NEC protocol?
*/
if ((ircode & ~not_code) != ircode) {
IR_dprintk(1, "NEC checksum error: code 0x%04x, not-code 0x%04x\n",
ircode, not_code);
return -EINVAL;
}
IR_dprintk(1, "NEC scancode 0x%04x\n", ircode);
return ircode;
err:
IR_dprintk(1, "NEC decoded failed at bit %d while decoding %luus time\n",
count, (evs[i].delta.tv_nsec + 500) / 1000);
return -EINVAL;
}
EXPORT_SYMBOL_GPL(ir_nec_decode);

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@ -0,0 +1,117 @@
/* 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 <media/ir-core.h>
/* Define the max number of bit transitions per IR keycode */
#define MAX_IR_EVENT_SIZE 256
int ir_raw_event_register(struct input_dev *input_dev)
{
struct ir_input_dev *ir = input_get_drvdata(input_dev);
int rc, size;
ir->raw = kzalloc(sizeof(*ir->raw), GFP_KERNEL);
size = sizeof(struct ir_raw_event) * MAX_IR_EVENT_SIZE * 2;
size = roundup_pow_of_two(size);
rc = kfifo_alloc(&ir->raw->kfifo, size, GFP_KERNEL);
return rc;
}
EXPORT_SYMBOL_GPL(ir_raw_event_register);
void ir_raw_event_unregister(struct input_dev *input_dev)
{
struct ir_input_dev *ir = input_get_drvdata(input_dev);
if (!ir->raw)
return;
kfifo_free(&ir->raw->kfifo);
kfree(ir->raw);
ir->raw = NULL;
}
EXPORT_SYMBOL_GPL(ir_raw_event_unregister);
int ir_raw_event_store(struct input_dev *input_dev, enum raw_event_type type)
{
struct ir_input_dev *ir = input_get_drvdata(input_dev);
struct timespec ts;
struct ir_raw_event event;
int rc;
if (!ir->raw)
return -EINVAL;
event.type = type;
event.delta.tv_sec = 0;
event.delta.tv_nsec = 0;
ktime_get_ts(&ts);
if (timespec_equal(&ir->raw->last_event, &event.delta))
event.type |= IR_START_EVENT;
else
event.delta = timespec_sub(ts, ir->raw->last_event);
memcpy(&ir->raw->last_event, &ts, sizeof(ts));
if (event.delta.tv_sec) {
event.type |= IR_START_EVENT;
event.delta.tv_sec = 0;
event.delta.tv_nsec = 0;
}
kfifo_in(&ir->raw->kfifo, &event, sizeof(event));
return rc;
}
EXPORT_SYMBOL_GPL(ir_raw_event_store);
int ir_raw_event_handle(struct input_dev *input_dev)
{
struct ir_input_dev *ir = input_get_drvdata(input_dev);
int rc;
struct ir_raw_event *evs;
int len, i;
/*
* Store the events into a temporary buffer. This allows calling more than
* one decoder to deal with the received data
*/
len = kfifo_len(&ir->raw->kfifo) / sizeof(*evs);
if (!len)
return 0;
evs = kmalloc(len * sizeof(*evs), GFP_ATOMIC);
for (i = 0; i < len; i++) {
rc = kfifo_out(&ir->raw->kfifo, &evs[i], sizeof(*evs));
if (rc != sizeof(*evs)) {
IR_dprintk(1, "overflow error: received %d instead of %zd\n",
rc, sizeof(*evs));
return -EINVAL;
}
IR_dprintk(2, "event type %d, time before event: %07luus\n",
evs[i].type, (evs[i].delta.tv_nsec + 500) / 1000);
}
rc = ir_nec_decode(input_dev, evs, len);
kfree(evs);
return rc;
}
EXPORT_SYMBOL_GPL(ir_raw_event_handle);

View File

@ -68,6 +68,7 @@ MODULE_PARM_DESC(disable_other_ir, "disable full codes of "
/* Helper functions for RC5 and NEC decoding at GPIO16 or GPIO18 */
static int saa7134_rc5_irq(struct saa7134_dev *dev);
static int saa7134_nec_irq(struct saa7134_dev *dev);
static int saa7134_raw_decode_irq(struct saa7134_dev *dev);
static void nec_task(unsigned long data);
static void saa7134_nec_timer(unsigned long data);
@ -403,10 +404,12 @@ void saa7134_input_irq(struct saa7134_dev *dev)
if (ir->nec_gpio) {
saa7134_nec_irq(dev);
} else if (!ir->polling && !ir->rc5_gpio) {
} else if (!ir->polling && !ir->rc5_gpio && !ir->raw_decode) {
build_key(dev);
} else if (ir->rc5_gpio) {
saa7134_rc5_irq(dev);
} else if (ir->raw_decode) {
saa7134_raw_decode_irq(dev);
}
}
@ -419,6 +422,23 @@ static void saa7134_input_timer(unsigned long data)
mod_timer(&ir->timer, jiffies + msecs_to_jiffies(ir->polling));
}
void ir_raw_decode_timer_end(unsigned long data)
{
struct saa7134_dev *dev = (struct saa7134_dev *)data;
struct card_ir *ir = dev->remote;
int rc;
/*
* FIXME: the IR key handling code should be called by the decoder,
* after implementing the repeat mode
*/
rc = ir_raw_event_handle(dev->remote->dev);
if (rc >= 0) {
ir_input_keydown(ir->dev, &ir->ir, rc);
ir_input_nokey(ir->dev, &ir->ir);
}
}
void saa7134_ir_start(struct saa7134_dev *dev, struct card_ir *ir)
{
if (ir->running)
@ -447,6 +467,11 @@ void saa7134_ir_start(struct saa7134_dev *dev, struct card_ir *ir)
setup_timer(&ir->timer_keyup, saa7134_nec_timer,
(unsigned long)dev);
tasklet_init(&ir->tlet, nec_task, (unsigned long)dev);
} else if (ir->raw_decode) {
/* set timer_end for code completion */
init_timer(&ir->timer_end);
ir->timer_end.function = ir_raw_decode_timer_end;
ir->timer_end.data = (unsigned long)dev;
}
}
@ -462,6 +487,9 @@ void saa7134_ir_stop(struct saa7134_dev *dev)
del_timer_sync(&ir->timer_end);
else if (ir->nec_gpio)
tasklet_kill(&ir->tlet);
else if (ir->raw_decode)
del_timer_sync(&ir->timer_end);
ir->running = 0;
}
@ -509,6 +537,7 @@ int saa7134_input_init1(struct saa7134_dev *dev)
int polling = 0;
int rc5_gpio = 0;
int nec_gpio = 0;
int raw_decode = 0;
u64 ir_type = IR_TYPE_OTHER;
int err;
@ -574,7 +603,7 @@ int saa7134_input_init1(struct saa7134_dev *dev)
ir_codes = &ir_codes_avermedia_m135a_rm_jx_table;
mask_keydown = 0x0040000;
mask_keycode = 0xffff;
nec_gpio = 1;
raw_decode = 1;
break;
case SAA7134_BOARD_AVERMEDIA_777:
case SAA7134_BOARD_AVERMEDIA_A16AR:
@ -755,6 +784,7 @@ int saa7134_input_init1(struct saa7134_dev *dev)
ir->polling = polling;
ir->rc5_gpio = rc5_gpio;
ir->nec_gpio = nec_gpio;
ir->raw_decode = raw_decode;
/* init input device */
snprintf(ir->name, sizeof(ir->name), "saa7134 IR (%s)",
@ -762,7 +792,7 @@ int saa7134_input_init1(struct saa7134_dev *dev)
snprintf(ir->phys, sizeof(ir->phys), "pci-%s/ir0",
pci_name(dev->pci));
if (ir_codes->ir_type != IR_TYPE_OTHER) {
if (ir_codes->ir_type != IR_TYPE_OTHER && !raw_decode) {
ir->props.allowed_protos = IR_TYPE_RC5 | IR_TYPE_NEC;
ir->props.priv = dev;
ir->props.change_protocol = saa7134_ir_change_protocol;
@ -790,6 +820,11 @@ int saa7134_input_init1(struct saa7134_dev *dev)
err = ir_input_register(ir->dev, ir_codes, &ir->props, MODULE_NAME);
if (err)
goto err_out_stop;
if (ir_codes->ir_type != IR_TYPE_OTHER) {
err = ir_raw_event_register(ir->dev);
if (err)
goto err_out_stop;
}
saa7134_ir_start(dev, ir);
@ -813,6 +848,7 @@ void saa7134_input_fini(struct saa7134_dev *dev)
return;
saa7134_ir_stop(dev);
ir_raw_event_unregister(dev->remote->dev);
ir_input_unregister(dev->remote->dev);
kfree(dev->remote);
dev->remote = NULL;
@ -919,6 +955,48 @@ void saa7134_probe_i2c_ir(struct saa7134_dev *dev)
i2c_new_device(&dev->i2c_adap, &info);
}
static int saa7134_raw_decode_irq(struct saa7134_dev *dev)
{
struct card_ir *ir = dev->remote;
unsigned long timeout;
int count, pulse, oldpulse;
/* Disable IR IRQ line */
saa_clearl(SAA7134_IRQ2, SAA7134_IRQ2_INTE_GPIO18);
/* Generate initial event */
saa_clearb(SAA7134_GPIO_GPMODE3, SAA7134_GPIO_GPRESCAN);
saa_setb(SAA7134_GPIO_GPMODE3, SAA7134_GPIO_GPRESCAN);
pulse = saa_readl(SAA7134_GPIO_GPSTATUS0 >> 2) & ir->mask_keydown;
ir_raw_event_store(dev->remote->dev, pulse? IR_PULSE : IR_SPACE);
#if 1
/* Wait up to 10 ms for event change */
oldpulse = pulse;
for (count = 0; count < 1000; count++) {
udelay(10);
/* rising SAA7134_GPIO_GPRESCAN reads the status */
saa_clearb(SAA7134_GPIO_GPMODE3, SAA7134_GPIO_GPRESCAN);
saa_setb(SAA7134_GPIO_GPMODE3, SAA7134_GPIO_GPRESCAN);
pulse = saa_readl(SAA7134_GPIO_GPSTATUS0 >> 2)
& ir->mask_keydown;
if (pulse != oldpulse)
break;
}
/* Store final event */
ir_raw_event_store(dev->remote->dev, pulse? IR_PULSE : IR_SPACE);
#endif
/* Wait 15 ms before deciding to do something else */
timeout = jiffies + jiffies_to_msecs(15);
mod_timer(&ir->timer_end, timeout);
/* Enable IR IRQ line */
saa_setl(SAA7134_IRQ2, SAA7134_IRQ2_INTE_GPIO18);
return 1;
}
static int saa7134_rc5_irq(struct saa7134_dev *dev)
{
struct card_ir *ir = dev->remote;
@ -961,7 +1039,6 @@ static int saa7134_rc5_irq(struct saa7134_dev *dev)
return 1;
}
/* On NEC protocol, One has 2.25 ms, and zero has 1.125 ms
The first pulse (start) has 9 + 4.5 ms
*/

View File

@ -82,6 +82,9 @@ struct card_ir {
/* NEC decoding */
u32 nec_gpio;
struct tasklet_struct tlet;
/* IR core raw decoding */
u32 raw_decode;
};
/* Routines from ir-functions.c */

View File

@ -16,6 +16,8 @@
#include <linux/input.h>
#include <linux/spinlock.h>
#include <linux/kfifo.h>
#include <linux/time.h>
extern int ir_core_debug;
#define IR_dprintk(level, fmt, arg...) if (ir_core_debug >= level) \
@ -27,6 +29,13 @@ extern int ir_core_debug;
#define IR_TYPE_NEC (1 << 2)
#define IR_TYPE_OTHER (((u64)1) << 63l)
enum raw_event_type {
IR_SPACE = (1 << 0),
IR_PULSE = (1 << 1),
IR_START_EVENT = (1 << 2),
IR_STOP_EVENT = (1 << 3),
};
struct ir_scancode {
u16 scancode;
u32 keycode;
@ -46,6 +55,15 @@ struct ir_dev_props {
int (*change_protocol)(void *priv, u64 ir_type);
};
struct ir_raw_event {
struct timespec delta; /* Time spent before event */
enum raw_event_type type; /* event type */
};
struct ir_raw_event_ctrl {
struct kfifo kfifo; /* fifo for the pulse/space events */
struct timespec last_event; /* when last event occurred */
};
struct ir_input_dev {
struct device dev; /* device */
@ -53,7 +71,9 @@ struct ir_input_dev {
struct ir_scancode_table rc_tab; /* scan/key table */
unsigned long devno; /* device number */
const struct ir_dev_props *props; /* Device properties */
struct ir_raw_event_ctrl *raw; /* for raw pulse/space events */
};
#define to_ir_input_dev(_attr) container_of(_attr, struct ir_input_dev, attr)
/* Routines from ir-keytable.c */
@ -72,4 +92,16 @@ void ir_input_unregister(struct input_dev *input_dev);
int ir_register_class(struct input_dev *input_dev);
void ir_unregister_class(struct input_dev *input_dev);
/* Routines from ir-raw-event.c */
int ir_raw_event_register(struct input_dev *input_dev);
void ir_raw_event_unregister(struct input_dev *input_dev);
int ir_raw_event_store(struct input_dev *input_dev, enum raw_event_type type);
int ir_raw_event_handle(struct input_dev *input_dev);
/* from ir-nec-decoder.c */
int ir_nec_decode(struct input_dev *input_dev,
struct ir_raw_event *evs,
int len);
#endif