1 files changed, 775 insertions, 0 deletions

diff --git a/drivers/media/video/pvrusb2/pvrusb2-sysfs.c b/drivers/media/video/pvrusb2/pvrusb2-sysfs.c
new file mode 100644
index 00000000000..c756b984505
--- /dev/null
+++ b/drivers/media/video/pvrusb2/pvrusb2-sysfs.c
@@ -0,0 +1,775 @@
+/*
+ *
+ *  $Id$
+ *
+ *  Copyright (C) 2005 Mike Isely <isely@pobox.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; either 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.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <asm/semaphore.h>
+#include "pvrusb2-sysfs.h"
+#include "pvrusb2-hdw.h"
+#include "pvrusb2-debug.h"
+#ifdef CONFIG_VIDEO_PVRUSB2_DEBUGIFC
+#include "pvrusb2-debugifc.h"
+#endif /* CONFIG_VIDEO_PVRUSB2_DEBUGIFC */
+
+#define pvr2_sysfs_trace(...) pvr2_trace(PVR2_TRACE_SYSFS,__VA_ARGS__)
+
+struct pvr2_sysfs {
+	struct pvr2_channel channel;
+	struct class_device *class_dev;
+#ifdef CONFIG_VIDEO_PVRUSB2_DEBUGIFC
+	struct pvr2_sysfs_debugifc *debugifc;
+#endif /* CONFIG_VIDEO_PVRUSB2_DEBUGIFC */
+	struct pvr2_sysfs_ctl_item *item_first;
+	struct pvr2_sysfs_ctl_item *item_last;
+	struct sysfs_ops kops;
+	struct kobj_type ktype;
+	struct class_device_attribute attr_v4l_minor_number;
+	struct class_device_attribute attr_unit_number;
+};
+
+#ifdef CONFIG_VIDEO_PVRUSB2_DEBUGIFC
+struct pvr2_sysfs_debugifc {
+	struct class_device_attribute attr_debugcmd;
+	struct class_device_attribute attr_debuginfo;
+};
+#endif /* CONFIG_VIDEO_PVRUSB2_DEBUGIFC */
+
+struct pvr2_sysfs_ctl_item {
+	struct class_device_attribute attr_name;
+	struct class_device_attribute attr_min;
+	struct class_device_attribute attr_max;
+	struct class_device_attribute attr_enum;
+	struct class_device_attribute attr_bits;
+	struct class_device_attribute attr_val;
+	struct class_device_attribute attr_custom;
+	struct pvr2_ctrl *cptr;
+	struct pvr2_sysfs *chptr;
+	struct pvr2_sysfs_ctl_item *item_next;
+	struct attribute *attr_gen[6];
+	struct attribute_group grp;
+	char name[80];
+};
+
+struct pvr2_sysfs_class {
+	struct class class;
+};
+
+static ssize_t show_name(int id,struct class_device *class_dev,char *buf)
+{
+	struct pvr2_ctrl *cptr;
+	struct pvr2_sysfs *sfp;
+	const char *name;
+
+	sfp = (struct pvr2_sysfs *)class_dev->class_data;
+	if (!sfp) return -EINVAL;
+	cptr = pvr2_hdw_get_ctrl_by_index(sfp->channel.hdw,id);
+	if (!cptr) return -EINVAL;
+
+	name = pvr2_ctrl_get_desc(cptr);
+	pvr2_sysfs_trace("pvr2_sysfs(%p) show_name(cid=%d) is %s",sfp,id,name);
+
+	if (!name) return -EINVAL;
+
+	return scnprintf(buf,PAGE_SIZE,"%s\n",name);
+}
+
+static ssize_t show_min(int id,struct class_device *class_dev,char *buf)
+{
+	struct pvr2_ctrl *cptr;
+	struct pvr2_sysfs *sfp;
+	long val;
+
+	sfp = (struct pvr2_sysfs *)class_dev->class_data;
+	if (!sfp) return -EINVAL;
+	cptr = pvr2_hdw_get_ctrl_by_index(sfp->channel.hdw,id);
+	if (!cptr) return -EINVAL;
+	val = pvr2_ctrl_get_min(cptr);
+
+	pvr2_sysfs_trace("pvr2_sysfs(%p) show_min(cid=%d) is %ld",sfp,id,val);
+
+	return scnprintf(buf,PAGE_SIZE,"%ld\n",val);
+}
+
+static ssize_t show_max(int id,struct class_device *class_dev,char *buf)
+{
+	struct pvr2_ctrl *cptr;
+	struct pvr2_sysfs *sfp;
+	long val;
+
+	sfp = (struct pvr2_sysfs *)class_dev->class_data;
+	if (!sfp) return -EINVAL;
+	cptr = pvr2_hdw_get_ctrl_by_index(sfp->channel.hdw,id);
+	if (!cptr) return -EINVAL;
+	val = pvr2_ctrl_get_max(cptr);
+
+	pvr2_sysfs_trace("pvr2_sysfs(%p) show_max(cid=%d) is %ld",sfp,id,val);
+
+	return scnprintf(buf,PAGE_SIZE,"%ld\n",val);
+}
+
+static ssize_t show_val_norm(int id,struct class_device *class_dev,char *buf)
+{
+	struct pvr2_ctrl *cptr;
+	struct pvr2_sysfs *sfp;
+	int val,ret;
+	unsigned int cnt = 0;
+
+	sfp = (struct pvr2_sysfs *)class_dev->class_data;
+	if (!sfp) return -EINVAL;
+	cptr = pvr2_hdw_get_ctrl_by_index(sfp->channel.hdw,id);
+	if (!cptr) return -EINVAL;
+
+	ret = pvr2_ctrl_get_value(cptr,&val);
+	if (ret < 0) return ret;
+
+	ret = pvr2_ctrl_value_to_sym(cptr,~0,val,
+				     buf,PAGE_SIZE-1,&cnt);
+
+	pvr2_sysfs_trace("pvr2_sysfs(%p) show_val_norm(cid=%d) is %.*s (%d)",
+			 sfp,id,cnt,buf,val);
+	buf[cnt] = '\n';
+	return cnt+1;
+}
+
+static ssize_t show_val_custom(int id,struct class_device *class_dev,char *buf)
+{
+	struct pvr2_ctrl *cptr;
+	struct pvr2_sysfs *sfp;
+	int val,ret;
+	unsigned int cnt = 0;
+
+	sfp = (struct pvr2_sysfs *)class_dev->class_data;
+	if (!sfp) return -EINVAL;
+	cptr = pvr2_hdw_get_ctrl_by_index(sfp->channel.hdw,id);
+	if (!cptr) return -EINVAL;
+
+	ret = pvr2_ctrl_get_value(cptr,&val);
+	if (ret < 0) return ret;
+
+	ret = pvr2_ctrl_custom_value_to_sym(cptr,~0,val,
+					    buf,PAGE_SIZE-1,&cnt);
+
+	pvr2_sysfs_trace("pvr2_sysfs(%p) show_val_custom(cid=%d) is %.*s (%d)",
+			 sfp,id,cnt,buf,val);
+	buf[cnt] = '\n';
+	return cnt+1;
+}
+
+static ssize_t show_enum(int id,struct class_device *class_dev,char *buf)
+{
+	struct pvr2_ctrl *cptr;
+	struct pvr2_sysfs *sfp;
+	long val;
+	unsigned int bcnt,ccnt,ecnt;
+
+	sfp = (struct pvr2_sysfs *)class_dev->class_data;
+	if (!sfp) return -EINVAL;
+	cptr = pvr2_hdw_get_ctrl_by_index(sfp->channel.hdw,id);
+	if (!cptr) return -EINVAL;
+	ecnt = pvr2_ctrl_get_cnt(cptr);
+	bcnt = 0;
+	for (val = 0; val < ecnt; val++) {
+		pvr2_ctrl_get_valname(cptr,val,buf+bcnt,PAGE_SIZE-bcnt,&ccnt);
+		bcnt += ccnt;
+		if (bcnt >= PAGE_SIZE) break;
+		buf[bcnt] = '\n';
+		bcnt++;
+	}
+	pvr2_sysfs_trace("pvr2_sysfs(%p) show_enum(cid=%d)",sfp,id);
+	return bcnt;
+}
+
+static ssize_t show_bits(int id,struct class_device *class_dev,char *buf)
+{
+	struct pvr2_ctrl *cptr;
+	struct pvr2_sysfs *sfp;
+	int valid_bits,msk;
+	unsigned int bcnt,ccnt;
+
+	sfp = (struct pvr2_sysfs *)class_dev->class_data;
+	if (!sfp) return -EINVAL;
+	cptr = pvr2_hdw_get_ctrl_by_index(sfp->channel.hdw,id);
+	if (!cptr) return -EINVAL;
+	valid_bits = pvr2_ctrl_get_mask(cptr);
+	bcnt = 0;
+	for (msk = 1; valid_bits; msk <<= 1) {
+		if (!(msk & valid_bits)) continue;
+		valid_bits &= ~msk;
+		pvr2_ctrl_get_valname(cptr,msk,buf+bcnt,PAGE_SIZE-bcnt,&ccnt);
+		bcnt += ccnt;
+		if (bcnt >= PAGE_SIZE) break;
+		buf[bcnt] = '\n';
+		bcnt++;
+	}
+	pvr2_sysfs_trace("pvr2_sysfs(%p) show_bits(cid=%d)",sfp,id);
+	return bcnt;
+}
+
+static int store_val_any(int id,int customfl,struct pvr2_sysfs *sfp,
+			 const char *buf,unsigned int count)
+{
+	struct pvr2_ctrl *cptr;
+	int ret;
+	int mask,val;
+
+	cptr = pvr2_hdw_get_ctrl_by_index(sfp->channel.hdw,id);
+	if (customfl) {
+		ret = pvr2_ctrl_custom_sym_to_value(cptr,buf,count,&mask,&val);
+	} else {
+		ret = pvr2_ctrl_sym_to_value(cptr,buf,count,&mask,&val);
+	}
+	if (ret < 0) return ret;
+	ret = pvr2_ctrl_set_mask_value(cptr,mask,val);
+	pvr2_hdw_commit_ctl(sfp->channel.hdw);
+	return ret;
+}
+
+static ssize_t store_val_norm(int id,struct class_device *class_dev,
+			     const char *buf,size_t count)
+{
+	struct pvr2_sysfs *sfp;
+	int ret;
+	sfp = (struct pvr2_sysfs *)class_dev->class_data;
+	ret = store_val_any(id,0,sfp,buf,count);
+	if (!ret) ret = count;
+	return ret;
+}
+
+static ssize_t store_val_custom(int id,struct class_device *class_dev,
+				const char *buf,size_t count)
+{
+	struct pvr2_sysfs *sfp;
+	int ret;
+	sfp = (struct pvr2_sysfs *)class_dev->class_data;
+	ret = store_val_any(id,1,sfp,buf,count);
+	if (!ret) ret = count;
+	return ret;
+}
+
+/*
+  Mike Isely <isely@pobox.com> 30-April-2005
+
+  This next batch of horrible preprocessor hackery is needed because the
+  kernel's class_device_attribute mechanism fails to pass the actual
+  attribute through to the show / store functions, which means we have no
+  way to package up any attribute-specific parameters, like for example the
+  control id.  So we work around this brain-damage by encoding the control
+  id into the show / store functions themselves and pick the function based
+  on the control id we're setting up.  These macros try to ease the pain.
+  Yuck.
+*/
+
+#define CREATE_SHOW_INSTANCE(sf_name,ctl_id) \
+static ssize_t sf_name##_##ctl_id(struct class_device *class_dev,char *buf) \
+{ return sf_name(ctl_id,class_dev,buf); }
+
+#define CREATE_STORE_INSTANCE(sf_name,ctl_id) \
+static ssize_t sf_name##_##ctl_id(struct class_device *class_dev,const char *buf,size_t count) \
+{ return sf_name(ctl_id,class_dev,buf,count); }
+
+#define CREATE_BATCH(ctl_id) \
+CREATE_SHOW_INSTANCE(show_name,ctl_id) \
+CREATE_SHOW_INSTANCE(show_min,ctl_id) \
+CREATE_SHOW_INSTANCE(show_max,ctl_id) \
+CREATE_SHOW_INSTANCE(show_val_norm,ctl_id) \
+CREATE_SHOW_INSTANCE(show_val_custom,ctl_id) \
+CREATE_SHOW_INSTANCE(show_enum,ctl_id) \
+CREATE_SHOW_INSTANCE(show_bits,ctl_id) \
+CREATE_STORE_INSTANCE(store_val_norm,ctl_id) \
+CREATE_STORE_INSTANCE(store_val_custom,ctl_id) \
+
+CREATE_BATCH(0)
+CREATE_BATCH(1)
+CREATE_BATCH(2)
+CREATE_BATCH(3)
+CREATE_BATCH(4)
+CREATE_BATCH(5)
+CREATE_BATCH(6)
+CREATE_BATCH(7)
+CREATE_BATCH(8)
+CREATE_BATCH(9)
+CREATE_BATCH(10)
+CREATE_BATCH(11)
+CREATE_BATCH(12)
+CREATE_BATCH(13)
+CREATE_BATCH(14)
+CREATE_BATCH(15)
+CREATE_BATCH(16)
+CREATE_BATCH(17)
+CREATE_BATCH(18)
+CREATE_BATCH(19)
+CREATE_BATCH(20)
+CREATE_BATCH(21)
+CREATE_BATCH(22)
+CREATE_BATCH(23)
+CREATE_BATCH(24)
+CREATE_BATCH(25)
+CREATE_BATCH(26)
+CREATE_BATCH(27)
+CREATE_BATCH(28)
+CREATE_BATCH(29)
+CREATE_BATCH(30)
+CREATE_BATCH(31)
+CREATE_BATCH(32)
+CREATE_BATCH(33)
+
+struct pvr2_sysfs_func_set {
+	ssize_t (*show_name)(struct class_device *,char *);
+	ssize_t (*show_min)(struct class_device *,char *);
+	ssize_t (*show_max)(struct class_device *,char *);
+	ssize_t (*show_enum)(struct class_device *,char *);
+	ssize_t (*show_bits)(struct class_device *,char *);
+	ssize_t (*show_val_norm)(struct class_device *,char *);
+	ssize_t (*store_val_norm)(struct class_device *,
+				  const char *,size_t);
+	ssize_t (*show_val_custom)(struct class_device *,char *);
+	ssize_t (*store_val_custom)(struct class_device *,
+				    const char *,size_t);
+};
+
+#define INIT_BATCH(ctl_id) \
+[ctl_id] = { \
+    .show_name = show_name_##ctl_id, \
+    .show_min = show_min_##ctl_id, \
+    .show_max = show_max_##ctl_id, \
+    .show_enum = show_enum_##ctl_id, \
+    .show_bits = show_bits_##ctl_id, \
+    .show_val_norm = show_val_norm_##ctl_id, \
+    .store_val_norm = store_val_norm_##ctl_id, \
+    .show_val_custom = show_val_custom_##ctl_id, \
+    .store_val_custom = store_val_custom_##ctl_id, \
+} \
+
+static struct pvr2_sysfs_func_set funcs[] = {
+	INIT_BATCH(0),
+	INIT_BATCH(1),
+	INIT_BATCH(2),
+	INIT_BATCH(3),
+	INIT_BATCH(4),
+	INIT_BATCH(5),
+	INIT_BATCH(6),
+	INIT_BATCH(7),
+	INIT_BATCH(8),
+	INIT_BATCH(9),
+	INIT_BATCH(10),
+	INIT_BATCH(11),
+	INIT_BATCH(12),
+	INIT_BATCH(13),
+	INIT_BATCH(14),
+	INIT_BATCH(15),
+	INIT_BATCH(16),
+	INIT_BATCH(17),
+	INIT_BATCH(18),
+	INIT_BATCH(19),
+	INIT_BATCH(20),
+	INIT_BATCH(21),
+	INIT_BATCH(22),
+	INIT_BATCH(23),
+	INIT_BATCH(24),
+	INIT_BATCH(25),
+	INIT_BATCH(26),
+	INIT_BATCH(27),
+	INIT_BATCH(28),
+	INIT_BATCH(29),
+	INIT_BATCH(30),
+	INIT_BATCH(31),
+	INIT_BATCH(32),
+	INIT_BATCH(33),
+};
+
+
+static void pvr2_sysfs_add_control(struct pvr2_sysfs *sfp,int ctl_id)
+{
+	struct pvr2_sysfs_ctl_item *cip;
+	struct pvr2_sysfs_func_set *fp;
+	struct pvr2_ctrl *cptr;
+	unsigned int cnt,acnt;
+
+	if ((ctl_id < 0) || (ctl_id >= (sizeof(funcs)/sizeof(funcs[0])))) {
+		return;
+	}
+
+	fp = funcs + ctl_id;
+	cptr = pvr2_hdw_get_ctrl_by_index(sfp->channel.hdw,ctl_id);
+	if (!cptr) return;
+
+	cip = kmalloc(sizeof(*cip),GFP_KERNEL);
+	if (!cip) return;
+	memset(cip,0,sizeof(*cip));
+	pvr2_sysfs_trace("Creating pvr2_sysfs_ctl_item id=%p",cip);
+
+	cip->cptr = cptr;
+
+	cip->chptr = sfp;
+	cip->item_next = 0;
+	if (sfp->item_last) {
+		sfp->item_last->item_next = cip;
+	} else {
+		sfp->item_first = cip;
+	}
+	sfp->item_last = cip;
+
+	cip->attr_name.attr.owner = THIS_MODULE;
+	cip->attr_name.attr.name = "name";
+	cip->attr_name.attr.mode = S_IRUGO;
+	cip->attr_name.show = fp->show_name;
+
+	cip->attr_min.attr.owner = THIS_MODULE;
+	cip->attr_min.attr.name = "min_val";
+	cip->attr_min.attr.mode = S_IRUGO;
+	cip->attr_min.show = fp->show_min;
+
+	cip->attr_max.attr.owner = THIS_MODULE;
+	cip->attr_max.attr.name = "max_val";
+	cip->attr_max.attr.mode = S_IRUGO;
+	cip->attr_max.show = fp->show_max;
+
+	cip->attr_val.attr.owner = THIS_MODULE;
+	cip->attr_val.attr.name = "cur_val";
+	cip->attr_val.attr.mode = S_IRUGO;
+
+	cip->attr_custom.attr.owner = THIS_MODULE;
+	cip->attr_custom.attr.name = "custom_val";
+	cip->attr_custom.attr.mode = S_IRUGO;
+
+	cip->attr_enum.attr.owner = THIS_MODULE;
+	cip->attr_enum.attr.name = "enum_val";
+	cip->attr_enum.attr.mode = S_IRUGO;
+	cip->attr_enum.show = fp->show_enum;
+
+	cip->attr_bits.attr.owner = THIS_MODULE;
+	cip->attr_bits.attr.name = "bit_val";
+	cip->attr_bits.attr.mode = S_IRUGO;
+	cip->attr_bits.show = fp->show_bits;
+
+	if (pvr2_ctrl_is_writable(cptr)) {
+		cip->attr_val.attr.mode |= S_IWUSR|S_IWGRP;
+		cip->attr_custom.attr.mode |= S_IWUSR|S_IWGRP;
+	}
+
+	acnt = 0;
+	cip->attr_gen[acnt++] = &cip->attr_name.attr;
+	cip->attr_gen[acnt++] = &cip->attr_val.attr;
+	cip->attr_val.show = fp->show_val_norm;
+	cip->attr_val.store = fp->store_val_norm;
+	if (pvr2_ctrl_has_custom_symbols(cptr)) {
+		cip->attr_gen[acnt++] = &cip->attr_custom.attr;
+		cip->attr_custom.show = fp->show_val_custom;
+		cip->attr_custom.store = fp->store_val_custom;
+	}
+	switch (pvr2_ctrl_get_type(cptr)) {
+	case pvr2_ctl_enum:
+		// Control is an enumeration
+		cip->attr_gen[acnt++] = &cip->attr_enum.attr;
+		break;
+	case pvr2_ctl_int:
+		// Control is an integer
+		cip->attr_gen[acnt++] = &cip->attr_min.attr;
+		cip->attr_gen[acnt++] = &cip->attr_max.attr;
+		break;
+	case pvr2_ctl_bitmask:
+		// Control is an bitmask
+		cip->attr_gen[acnt++] = &cip->attr_bits.attr;
+		break;
+	default: break;
+	}
+
+	cnt = scnprintf(cip->name,sizeof(cip->name)-1,"ctl_%s",
+			pvr2_ctrl_get_name(cptr));
+	cip->name[cnt] = 0;
+	cip->grp.name = cip->name;
+	cip->grp.attrs = cip->attr_gen;
+
+	sysfs_create_group(&sfp->class_dev->kobj,&cip->grp);
+}
+
+#ifdef CONFIG_VIDEO_PVRUSB2_DEBUGIFC
+static ssize_t debuginfo_show(struct class_device *,char *);
+static ssize_t debugcmd_show(struct class_device *,char *);
+static ssize_t debugcmd_store(struct class_device *,const char *,size_t count);
+
+static void pvr2_sysfs_add_debugifc(struct pvr2_sysfs *sfp)
+{
+	struct pvr2_sysfs_debugifc *dip;
+	dip = kmalloc(sizeof(*dip),GFP_KERNEL);
+	if (!dip) return;
+	memset(dip,0,sizeof(*dip));
+	dip->attr_debugcmd.attr.owner = THIS_MODULE;
+	dip->attr_debugcmd.attr.name = "debugcmd";
+	dip->attr_debugcmd.attr.mode = S_IRUGO|S_IWUSR|S_IWGRP;
+	dip->attr_debugcmd.show = debugcmd_show;
+	dip->attr_debugcmd.store = debugcmd_store;
+	dip->attr_debuginfo.attr.owner = THIS_MODULE;
+	dip->attr_debuginfo.attr.name = "debuginfo";
+	dip->attr_debuginfo.attr.mode = S_IRUGO;
+	dip->attr_debuginfo.show = debuginfo_show;
+	sfp->debugifc = dip;
+	class_device_create_file(sfp->class_dev,&dip->attr_debugcmd);
+	class_device_create_file(sfp->class_dev,&dip->attr_debuginfo);
+}
+
+
+static void pvr2_sysfs_tear_down_debugifc(struct pvr2_sysfs *sfp)
+{
+	if (!sfp->debugifc) return;
+	class_device_remove_file(sfp->class_dev,
+				 &sfp->debugifc->attr_debuginfo);
+	class_device_remove_file(sfp->class_dev,&sfp->debugifc->attr_debugcmd);
+	kfree(sfp->debugifc);
+	sfp->debugifc = 0;
+}
+#endif /* CONFIG_VIDEO_PVRUSB2_DEBUGIFC */
+
+
+static void pvr2_sysfs_add_controls(struct pvr2_sysfs *sfp)
+{
+	unsigned int idx,cnt;
+	cnt = pvr2_hdw_get_ctrl_count(sfp->channel.hdw);
+	for (idx = 0; idx < cnt; idx++) {
+		pvr2_sysfs_add_control(sfp,idx);
+	}
+}
+
+
+static void pvr2_sysfs_tear_down_controls(struct pvr2_sysfs *sfp)
+{
+	struct pvr2_sysfs_ctl_item *cip1,*cip2;
+	for (cip1 = sfp->item_first; cip1; cip1 = cip2) {
+		cip2 = cip1->item_next;
+		sysfs_remove_group(&sfp->class_dev->kobj,&cip1->grp);
+		pvr2_sysfs_trace("Destroying pvr2_sysfs_ctl_item id=%p",cip1);
+		kfree(cip1);
+	}
+}
+
+
+static void pvr2_sysfs_class_release(struct class *class)
+{
+	struct pvr2_sysfs_class *clp;
+	clp = container_of(class,struct pvr2_sysfs_class,class);
+	pvr2_sysfs_trace("Destroying pvr2_sysfs_class id=%p",clp);
+	kfree(clp);
+}
+
+
+static void pvr2_sysfs_release(struct class_device *class_dev)
+{
+	pvr2_sysfs_trace("Releasing class_dev id=%p",class_dev);
+	kfree(class_dev);
+}
+
+
+static void class_dev_destroy(struct pvr2_sysfs *sfp)
+{
+	if (!sfp->class_dev) return;
+#ifdef CONFIG_VIDEO_PVRUSB2_DEBUGIFC
+	pvr2_sysfs_tear_down_debugifc(sfp);
+#endif /* CONFIG_VIDEO_PVRUSB2_DEBUGIFC */
+	pvr2_sysfs_tear_down_controls(sfp);
+	class_device_remove_file(sfp->class_dev,&sfp->attr_v4l_minor_number);
+	class_device_remove_file(sfp->class_dev,&sfp->attr_unit_number);
+	pvr2_sysfs_trace("Destroying class_dev id=%p",sfp->class_dev);
+	sfp->class_dev->class_data = 0;
+	class_device_unregister(sfp->class_dev);
+	sfp->class_dev = 0;
+}
+
+
+static ssize_t v4l_minor_number_show(struct class_device *class_dev,char *buf)
+{
+	struct pvr2_sysfs *sfp;
+	sfp = (struct pvr2_sysfs *)class_dev->class_data;
+	if (!sfp) return -EINVAL;
+	return scnprintf(buf,PAGE_SIZE,"%d\n",
+			 pvr2_hdw_v4l_get_minor_number(sfp->channel.hdw));
+}
+
+
+static ssize_t unit_number_show(struct class_device *class_dev,char *buf)
+{
+	struct pvr2_sysfs *sfp;
+	sfp = (struct pvr2_sysfs *)class_dev->class_data;
+	if (!sfp) return -EINVAL;
+	return scnprintf(buf,PAGE_SIZE,"%d\n",
+			 pvr2_hdw_get_unit_number(sfp->channel.hdw));
+}
+
+
+static void class_dev_create(struct pvr2_sysfs *sfp,
+			     struct pvr2_sysfs_class *class_ptr)
+{
+	struct usb_device *usb_dev;
+	struct class_device *class_dev;
+	usb_dev = pvr2_hdw_get_dev(sfp->channel.hdw);
+	if (!usb_dev) return;
+	class_dev = kmalloc(sizeof(*class_dev),GFP_KERNEL);
+	if (!class_dev) return;
+	memset(class_dev,0,sizeof(*class_dev));
+
+	pvr2_sysfs_trace("Creating class_dev id=%p",class_dev);
+
+	class_dev->class = &class_ptr->class;
+	if (pvr2_hdw_get_sn(sfp->channel.hdw)) {
+		snprintf(class_dev->class_id,BUS_ID_SIZE,"sn-%lu",
+			 pvr2_hdw_get_sn(sfp->channel.hdw));
+	} else if (pvr2_hdw_get_unit_number(sfp->channel.hdw) >= 0) {
+		snprintf(class_dev->class_id,BUS_ID_SIZE,"unit-%c",
+			 pvr2_hdw_get_unit_number(sfp->channel.hdw) + 'a');
+	} else {
+		kfree(class_dev);
+		return;
+	}
+
+	class_dev->dev = &usb_dev->dev;
+
+	sfp->class_dev = class_dev;
+	class_dev->class_data = sfp;
+	class_device_register(class_dev);
+
+	sfp->attr_v4l_minor_number.attr.owner = THIS_MODULE;
+	sfp->attr_v4l_minor_number.attr.name = "v4l_minor_number";
+	sfp->attr_v4l_minor_number.attr.mode = S_IRUGO;
+	sfp->attr_v4l_minor_number.show = v4l_minor_number_show;
+	sfp->attr_v4l_minor_number.store = 0;
+	class_device_create_file(sfp->class_dev,&sfp->attr_v4l_minor_number);
+	sfp->attr_unit_number.attr.owner = THIS_MODULE;
+	sfp->attr_unit_number.attr.name = "unit_number";
+	sfp->attr_unit_number.attr.mode = S_IRUGO;
+	sfp->attr_unit_number.show = unit_number_show;
+	sfp->attr_unit_number.store = 0;
+	class_device_create_file(sfp->class_dev,&sfp->attr_unit_number);
+
+	pvr2_sysfs_add_controls(sfp);
+#ifdef CONFIG_VIDEO_PVRUSB2_DEBUGIFC
+	pvr2_sysfs_add_debugifc(sfp);
+#endif /* CONFIG_VIDEO_PVRUSB2_DEBUGIFC */
+}
+
+
+static void pvr2_sysfs_internal_check(struct pvr2_channel *chp)
+{
+	struct pvr2_sysfs *sfp;
+	sfp = container_of(chp,struct pvr2_sysfs,channel);
+	if (!sfp->channel.mc_head->disconnect_flag) return;
+	pvr2_trace(PVR2_TRACE_STRUCT,"Destroying pvr2_sysfs id=%p",sfp);
+	class_dev_destroy(sfp);
+	pvr2_channel_done(&sfp->channel);
+	kfree(sfp);
+}
+
+
+struct pvr2_sysfs *pvr2_sysfs_create(struct pvr2_context *mp,
+				     struct pvr2_sysfs_class *class_ptr)
+{
+	struct pvr2_sysfs *sfp;
+	sfp = kmalloc(sizeof(*sfp),GFP_KERNEL);
+	if (!sfp) return sfp;
+	memset(sfp,0,sizeof(*sfp));
+	pvr2_trace(PVR2_TRACE_STRUCT,"Creating pvr2_sysfs id=%p",sfp);
+	pvr2_channel_init(&sfp->channel,mp);
+	sfp->channel.check_func = pvr2_sysfs_internal_check;
+
+	class_dev_create(sfp,class_ptr);
+	return sfp;
+}
+
+
+static int pvr2_sysfs_hotplug(struct class_device *cd,char **envp,
+			      int numenvp,char *buf,int size)
+{
+	/* Even though we don't do anything here, we still need this function
+	   because sysfs will still try to call it. */
+	return 0;
+}
+
+struct pvr2_sysfs_class *pvr2_sysfs_class_create(void)
+{
+	struct pvr2_sysfs_class *clp;
+	clp = kmalloc(sizeof(*clp),GFP_KERNEL);
+	if (!clp) return clp;
+	memset(clp,0,sizeof(*clp));
+	pvr2_sysfs_trace("Creating pvr2_sysfs_class id=%p",clp);
+	clp->class.name = "pvrusb2";
+	clp->class.class_release = pvr2_sysfs_class_release;
+	clp->class.release = pvr2_sysfs_release;
+	clp->class.uevent = pvr2_sysfs_hotplug;
+	if (class_register(&clp->class)) {
+		pvr2_sysfs_trace(
+			"Registration failed for pvr2_sysfs_class id=%p",clp);
+		kfree(clp);
+		clp = 0;
+	}
+	return clp;
+}
+
+
+void pvr2_sysfs_class_destroy(struct pvr2_sysfs_class *clp)
+{
+	class_unregister(&clp->class);
+}
+
+
+#ifdef CONFIG_VIDEO_PVRUSB2_DEBUGIFC
+static ssize_t debuginfo_show(struct class_device *class_dev,char *buf)
+{
+	struct pvr2_sysfs *sfp;
+	sfp = (struct pvr2_sysfs *)class_dev->class_data;
+	if (!sfp) return -EINVAL;
+	pvr2_hdw_trigger_module_log(sfp->channel.hdw);
+	return pvr2_debugifc_print_info(sfp->channel.hdw,buf,PAGE_SIZE);
+}
+
+
+static ssize_t debugcmd_show(struct class_device *class_dev,char *buf)
+{
+	struct pvr2_sysfs *sfp;
+	sfp = (struct pvr2_sysfs *)class_dev->class_data;
+	if (!sfp) return -EINVAL;
+	return pvr2_debugifc_print_status(sfp->channel.hdw,buf,PAGE_SIZE);
+}
+
+
+static ssize_t debugcmd_store(struct class_device *class_dev,
+			      const char *buf,size_t count)
+{
+	struct pvr2_sysfs *sfp;
+	int ret;
+
+	sfp = (struct pvr2_sysfs *)class_dev->class_data;
+	if (!sfp) return -EINVAL;
+
+	ret = pvr2_debugifc_docmd(sfp->channel.hdw,buf,count);
+	if (ret < 0) return ret;
+	return count;
+}
+#endif /* CONFIG_VIDEO_PVRUSB2_DEBUGIFC */
+
+
+/*
+  Stuff for Emacs to see, in order to encourage consistent editing style:
+  *** Local Variables: ***
+  *** mode: c ***
+  *** fill-column: 75 ***
+  *** tab-width: 8 ***
+  *** c-basic-offset: 8 ***
+  *** End: ***
+  */