V4L/DVB (13633): ir-core: create a new class for remote controllers

Add sysfs skeleton to export remote controller information via
/sys/class/irrcv.

For now, the code doesn't do much. It just exports an attribute that
is meant to  report and control the IR protocol used by the keytable.
However, the callbacks for this new attribute weren't set yet.

Also, it lacks symlinks to the used event interface.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/IR/Makefile

 ir-common-objs  := ir-functions.o ir-keymaps.o
-ir-core-objs	:= ir-keytable.o
+ir-core-objs	:= ir-keytable.o ir-sysfs.o
 
 obj-$(CONFIG_IR_CORE) += ir-core.o
 obj-$(CONFIG_VIDEO_IR) += ir-common.o

drivers/media/IR/ir-keytable.c

@@ -447,12 +447,21 @@ int ir_input_register(struct input_dev *input_dev,
 	input_set_drvdata(input_dev, ir_dev);
 
 	rc = input_register_device(input_dev);
+	if (rc < 0)
+		goto err;
+
+	rc = ir_register_class(input_dev);
 	if (rc < 0) {
-		kfree(rc_tab->scan);
-		kfree(ir_dev);
-		input_set_drvdata(input_dev, NULL);
+		input_unregister_device(input_dev);
+		goto err;
 	}
 
+	return 0;
+
+err:
+	kfree(rc_tab->scan);
+	kfree(ir_dev);
+	input_set_drvdata(input_dev, NULL);
 	return rc;
 }
 EXPORT_SYMBOL_GPL(ir_input_register);
@@ -472,6 +481,8 @@ void ir_input_unregister(struct input_dev *dev)
 	kfree(rc_tab->scan);
 	rc_tab->scan = NULL;
 
+	ir_unregister_class(dev);
+
 	kfree(ir_dev);
 	input_unregister_device(dev);
 }

drivers/media/IR/ir-sysfs.c

+/* ir-register.c - handle IR scancode->keycode tables
+ *
+ * Copyright (C) 2009 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/input.h>
+#include <linux/device.h>
+#include <media/ir-core.h>
+
+#define IRRCV_NUM_DEVICES	256
+
+unsigned long ir_core_dev_number;
+
+static struct class *ir_input_class;
+
+static DEVICE_ATTR(ir_protocol, S_IRUGO | S_IWUSR, NULL, NULL);
+
+static struct attribute *ir_dev_attrs[] = {
+	&dev_attr_ir_protocol.attr,
+};
+
+int ir_register_class(struct input_dev *input_dev)
+{
+	int rc;
+	struct kobject *kobj;
+
+	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
+	int devno = find_first_zero_bit(&ir_core_dev_number,
+					IRRCV_NUM_DEVICES);
+
+	if (unlikely(devno < 0))
+		return devno;
+
+	ir_dev->attr.attrs = ir_dev_attrs;
+	ir_dev->class_dev = device_create(ir_input_class, NULL,
+					  input_dev->dev.devt, ir_dev,
+					  "irrcv%d", devno);
+	kobj = &ir_dev->class_dev->kobj;
+
+	printk(KERN_WARNING "Creating IR device %s\n", kobject_name(kobj));
+	rc = sysfs_create_group(kobj, &ir_dev->attr);
+	if (unlikely(rc < 0)) {
+		device_destroy(ir_input_class, input_dev->dev.devt);
+		return -ENOMEM;
+	}
+
+	ir_dev->devno = devno;
+	set_bit(devno, &ir_core_dev_number);
+
+	return 0;
+};
+
+void ir_unregister_class(struct input_dev *input_dev)
+{
+	struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
+	struct kobject *kobj;
+
+	clear_bit(ir_dev->devno, &ir_core_dev_number);
+
+	kobj = &ir_dev->class_dev->kobj;
+
+	sysfs_remove_group(kobj, &ir_dev->attr);
+	device_destroy(ir_input_class, input_dev->dev.devt);
+
+	kfree(ir_dev->attr.name);
+}
+
+static int __init ir_core_init(void)
+{
+	ir_input_class = class_create(THIS_MODULE, "irrcv");
+	if (IS_ERR(ir_input_class)) {
+		printk(KERN_ERR "ir_core: unable to register irrcv class\n");
+		return PTR_ERR(ir_input_class);
+	}
+
+	return 0;
+}
+
+static void __exit ir_core_exit(void)
+{
+	class_destroy(ir_input_class);
+}
+
+module_init(ir_core_init);
+module_exit(ir_core_exit);

include/media/ir-core.h

@@ -42,8 +42,11 @@ struct ir_scancode_table {
 };
 
 struct ir_input_dev {
-	struct input_dev		*dev;
-	struct ir_scancode_table	rc_tab;
+	struct input_dev		*dev;		/* Input device*/
+	struct ir_scancode_table	rc_tab;		/* scan/key table */
+	unsigned long			devno;		/* device number */
+	struct attribute_group		attr;		/* IR attributes */
+	struct device			*class_dev;	/* virtual class dev */
 };
 
 /* Routines from ir-keytable.c */
@@ -59,4 +62,9 @@ int ir_input_register(struct input_dev *dev,
 		      struct ir_scancode_table *ir_codes);
 void ir_input_unregister(struct input_dev *input_dev);
 
+/* Routines from ir-sysfs.c */
+
+int ir_register_class(struct input_dev *input_dev);
+void ir_unregister_class(struct input_dev *input_dev);
+
 #endif