V4L/DVB: IR: add ir-core to lirc userspace decoder bridge driver

v2: copy of buffer data from userspace done inside this plugin/driver,
keeping the actual drivers minimal, and more flexible in what we can
deliver to them later on (they may be fed from within kernelspace later
on, by an in-kernel IR encoder).
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/IR/Kconfig

@@ -69,6 +69,16 @@ config IR_SONY_DECODER
 	   Enable this option if you have an infrared remote control which
 	   uses the Sony protocol, and you need software decoding support.
 
+config IR_LIRC_CODEC
+	tristate "Enable IR to LIRC bridge"
+	depends on IR_CORE
+	depends on LIRC
+	default y
+
+	---help---
+	   Enable this option to pass raw IR to and from userspace via
+	   the LIRC interface.
+
 config IR_IMON
 	tristate "SoundGraph iMON Receiver and Display"
 	depends on USB_ARCH_HAS_HCD

drivers/media/IR/Makefile

@@ -11,6 +11,7 @@ obj-$(CONFIG_IR_RC5_DECODER) += ir-rc5-decoder.o
 obj-$(CONFIG_IR_RC6_DECODER) += ir-rc6-decoder.o
 obj-$(CONFIG_IR_JVC_DECODER) += ir-jvc-decoder.o
 obj-$(CONFIG_IR_SONY_DECODER) += ir-sony-decoder.o
+obj-$(CONFIG_IR_LIRC_CODEC) += ir-lirc-codec.o
 
 # stand-alone IR receivers/transmitters
 obj-$(CONFIG_IR_IMON) += imon.o

drivers/media/IR/ir-core-priv.h

@@ -73,6 +73,11 @@ struct ir_raw_event_ctrl {
 		bool first;
 		bool toggle;
 	} jvc;
+	struct lirc_codec {
+		struct ir_input_dev *ir_dev;
+		struct lirc_driver *drv;
+		int lircdata;
+	} lirc;
 };
 
 /* macros for IR decoders */
@@ -164,4 +169,12 @@ void ir_raw_init(void);
 #define load_sony_decode()	0
 #endif
 
+/* from ir-lirc-codec.c */
+#ifdef CONFIG_IR_LIRC_CODEC_MODULE
+#define load_lirc_codec()	request_module("ir-lirc-codec")
+#else
+#define load_lirc_codec()	0
+#endif
+
+
 #endif /* _IR_RAW_EVENT */

drivers/media/IR/ir-lirc-codec.c

+/* ir-lirc-codec.c - ir-core to classic lirc interface bridge
+ *
+ * Copyright (C) 2010 by Jarod Wilson <jarod@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/sched.h>
+#include <linux/wait.h>
+#include <media/lirc.h>
+#include <media/ir-core.h>
+#include "ir-core-priv.h"
+#include "lirc_dev.h"
+
+#define LIRCBUF_SIZE 256
+
+/**
+ * ir_lirc_decode() - Send raw IR data to lirc_dev to be relayed to the
+ *		      lircd userspace daemon for decoding.
+ * @input_dev:	the struct input_dev descriptor of the device
+ * @duration:	the struct ir_raw_event descriptor of the pulse/space
+ *
+ * This function returns -EINVAL if the lirc interfaces aren't wired up.
+ */
+static int ir_lirc_decode(struct input_dev *input_dev, struct ir_raw_event ev)
+{
+	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
+
+	if (!(ir_dev->raw->enabled_protocols & IR_TYPE_LIRC))
+		return 0;
+
+	if (!ir_dev->raw->lirc.drv || !ir_dev->raw->lirc.drv->rbuf)
+		return -EINVAL;
+
+	IR_dprintk(2, "LIRC data transfer started (%uus %s)\n",
+		   TO_US(ev.duration), TO_STR(ev.pulse));
+
+	ir_dev->raw->lirc.lircdata += ev.duration / 1000;
+	if (ev.pulse)
+		ir_dev->raw->lirc.lircdata |= PULSE_BIT;
+
+	lirc_buffer_write(ir_dev->raw->lirc.drv->rbuf,
+			  (unsigned char *) &ir_dev->raw->lirc.lircdata);
+	wake_up(&ir_dev->raw->lirc.drv->rbuf->wait_poll);
+
+	ir_dev->raw->lirc.lircdata = 0;
+
+	return 0;
+}
+
+static ssize_t ir_lirc_transmit_ir(struct file *file, const char *buf,
+				   size_t n, loff_t *ppos)
+{
+	struct lirc_codec *lirc;
+	struct ir_input_dev *ir_dev;
+	int *txbuf; /* buffer with values to transmit */
+	int ret = 0, count;
+
+	lirc = lirc_get_pdata(file);
+	if (!lirc)
+		return -EFAULT;
+
+	if (n % sizeof(int))
+		return -EINVAL;
+
+	count = n / sizeof(int);
+	if (count > LIRCBUF_SIZE || count % 2 == 0)
+		return -EINVAL;
+
+	txbuf = kzalloc(sizeof(int) * LIRCBUF_SIZE, GFP_KERNEL);
+	if (!txbuf)
+		return -ENOMEM;
+
+	if (copy_from_user(txbuf, buf, n)) {
+		ret = -EFAULT;
+		goto out;
+	}
+
+	ir_dev = lirc->ir_dev;
+	if (!ir_dev) {
+		ret = -EFAULT;
+		goto out;
+	}
+
+	if (ir_dev->props && ir_dev->props->tx_ir)
+		ret = ir_dev->props->tx_ir(ir_dev->props->priv, txbuf, (u32)n);
+
+out:
+	kfree(txbuf);
+	return ret;
+}
+
+static int ir_lirc_ioctl(struct inode *node, struct file *filep,
+			 unsigned int cmd, unsigned long arg)
+{
+	struct lirc_codec *lirc;
+	struct ir_input_dev *ir_dev;
+	int ret = 0;
+	void *drv_data;
+	unsigned long val;
+
+	lirc = lirc_get_pdata(filep);
+	if (!lirc)
+		return -EFAULT;
+
+	ir_dev = lirc->ir_dev;
+	if (!ir_dev || !ir_dev->props || !ir_dev->props->priv)
+		return -EFAULT;
+
+	drv_data = ir_dev->props->priv;
+
+	switch (cmd) {
+	case LIRC_SET_TRANSMITTER_MASK:
+		ret = get_user(val, (unsigned long *)arg);
+		if (ret)
+			return ret;
+
+		if (ir_dev->props && ir_dev->props->s_tx_mask)
+			ret = ir_dev->props->s_tx_mask(drv_data, (u32)val);
+		else
+			return -EINVAL;
+		break;
+
+	case LIRC_SET_SEND_CARRIER:
+		ret = get_user(val, (unsigned long *)arg);
+		if (ret)
+			return ret;
+
+		if (ir_dev->props && ir_dev->props->s_tx_carrier)
+			ir_dev->props->s_tx_carrier(drv_data, (u32)val);
+		else
+			return -EINVAL;
+		break;
+
+	case LIRC_GET_SEND_MODE:
+		val = LIRC_CAN_SEND_PULSE & LIRC_CAN_SEND_MASK;
+		ret = put_user(val, (unsigned long *)arg);
+		break;
+
+	case LIRC_SET_SEND_MODE:
+		ret = get_user(val, (unsigned long *)arg);
+		if (ret)
+			return ret;
+
+		if (val != (LIRC_MODE_PULSE & LIRC_CAN_SEND_MASK))
+			return -EINVAL;
+		break;
+
+	default:
+		return lirc_dev_fop_ioctl(node, filep, cmd, arg);
+	}
+
+	return ret;
+}
+
+static int ir_lirc_open(void *data)
+{
+	return 0;
+}
+
+static void ir_lirc_close(void *data)
+{
+	return;
+}
+
+static struct file_operations lirc_fops = {
+	.owner		= THIS_MODULE,
+	.write		= ir_lirc_transmit_ir,
+	.ioctl		= ir_lirc_ioctl,
+	.read		= lirc_dev_fop_read,
+	.poll		= lirc_dev_fop_poll,
+	.open		= lirc_dev_fop_open,
+	.release	= lirc_dev_fop_close,
+};
+
+static int ir_lirc_register(struct input_dev *input_dev)
+{
+	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
+	struct lirc_driver *drv;
+	struct lirc_buffer *rbuf;
+	int rc = -ENOMEM;
+	unsigned long features;
+
+	drv = kzalloc(sizeof(struct lirc_driver), GFP_KERNEL);
+	if (!drv)
+		return rc;
+
+	rbuf = kzalloc(sizeof(struct lirc_buffer), GFP_KERNEL);
+	if (!drv)
+		goto rbuf_alloc_failed;
+
+	rc = lirc_buffer_init(rbuf, sizeof(int), LIRCBUF_SIZE);
+	if (rc)
+		goto rbuf_init_failed;
+
+	features = LIRC_CAN_REC_MODE2;
+	if (ir_dev->props->tx_ir) {
+		features |= LIRC_CAN_SEND_PULSE;
+		if (ir_dev->props->s_tx_mask)
+			features |= LIRC_CAN_SET_TRANSMITTER_MASK;
+		if (ir_dev->props->s_tx_carrier)
+			features |= LIRC_CAN_SET_SEND_CARRIER;
+	}
+
+	snprintf(drv->name, sizeof(drv->name), "ir-lirc-codec (%s)",
+		 ir_dev->driver_name);
+	drv->minor = -1;
+	drv->features = features;
+	drv->data = &ir_dev->raw->lirc;
+	drv->rbuf = rbuf;
+	drv->set_use_inc = &ir_lirc_open;
+	drv->set_use_dec = &ir_lirc_close;
+	drv->code_length = sizeof(struct ir_raw_event) * 8;
+	drv->fops = &lirc_fops;
+	drv->dev = &ir_dev->dev;
+	drv->owner = THIS_MODULE;
+
+	drv->minor = lirc_register_driver(drv);
+	if (drv->minor < 0) {
+		rc = -ENODEV;
+		goto lirc_register_failed;
+	}
+
+	ir_dev->raw->lirc.drv = drv;
+	ir_dev->raw->lirc.ir_dev = ir_dev;
+	ir_dev->raw->lirc.lircdata = PULSE_MASK;
+
+	return 0;
+
+lirc_register_failed:
+rbuf_init_failed:
+	kfree(rbuf);
+rbuf_alloc_failed:
+	kfree(drv);
+
+	return rc;
+}
+
+static int ir_lirc_unregister(struct input_dev *input_dev)
+{
+	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
+	struct lirc_codec *lirc = &ir_dev->raw->lirc;
+
+	lirc_unregister_driver(lirc->drv->minor);
+	lirc_buffer_free(lirc->drv->rbuf);
+	kfree(lirc->drv);
+
+	return 0;
+}
+
+static struct ir_raw_handler lirc_handler = {
+	.protocols	= IR_TYPE_LIRC,
+	.decode		= ir_lirc_decode,
+	.raw_register	= ir_lirc_register,
+	.raw_unregister	= ir_lirc_unregister,
+};
+
+static int __init ir_lirc_codec_init(void)
+{
+	ir_raw_handler_register(&lirc_handler);
+
+	printk(KERN_INFO "IR LIRC bridge handler initialized\n");
+	return 0;
+}
+
+static void __exit ir_lirc_codec_exit(void)
+{
+	ir_raw_handler_unregister(&lirc_handler);
+}
+
+module_init(ir_lirc_codec_init);
+module_exit(ir_lirc_codec_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jarod Wilson <jarod@redhat.com>");
+MODULE_AUTHOR("Red Hat Inc. (http://www.redhat.com)");
+MODULE_DESCRIPTION("LIRC IR handler bridge");

drivers/media/IR/ir-raw-event.c

@@ -253,6 +253,7 @@ static void init_decoders(struct work_struct *work)
 	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 ir-core.h

drivers/media/IR/ir-sysfs.c

@@ -43,6 +43,7 @@ static struct {
 	{ IR_TYPE_RC6,		"rc-6"		},
 	{ IR_TYPE_JVC,		"jvc"		},
 	{ IR_TYPE_SONY,		"sony"		},
+	{ IR_TYPE_LIRC,		"lirc"		},
 };
 
 #define PROTO_NONE	"none"

include/media/rc-map.h

@@ -17,10 +17,12 @@
 #define IR_TYPE_RC6	(1  << 2)	/* Philips RC6 protocol */
 #define IR_TYPE_JVC	(1  << 3)	/* JVC protocol */
 #define IR_TYPE_SONY	(1  << 4)	/* Sony12/15/20 protocol */
+#define IR_TYPE_LIRC	(1  << 30)	/* Pass raw IR to lirc userspace */
 #define IR_TYPE_OTHER	(1u << 31)
 
 #define IR_TYPE_ALL (IR_TYPE_RC5 | IR_TYPE_NEC  | IR_TYPE_RC6  | \
-		     IR_TYPE_JVC | IR_TYPE_SONY | IR_TYPE_OTHER)
+		     IR_TYPE_JVC | IR_TYPE_SONY | IR_TYPE_LIRC | \
+		     IR_TYPE_OTHER)
 
 struct ir_scancode {
 	u32	scancode;