From e8d1d9defe31667f3ec4fd43a6c01f8e1e042d12 Mon Sep 17 00:00:00 2001
From: Michael Hunold <hunold@linuxtv.org>
Date: Tue, 7 Oct 2003 18:47:02 -0700
Subject: [PATCH] [PATCH] multiple device *read* opens support

 - allow multiple read device opens
---
 drivers/media/dvb/dvb-core/dvb_frontend.c |  1 +
 drivers/media/dvb/dvb-core/dvbdev.c       | 11 +++++++++--
 drivers/media/dvb/dvb-core/dvbdev.h       |  8 +++++++-
 3 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/drivers/media/dvb/dvb-core/dvb_frontend.c b/drivers/media/dvb/dvb-core/dvb_frontend.c
index fc4c01309c80..f5e38f1e1ba2 100644
--- a/drivers/media/dvb/dvb-core/dvb_frontend.c
+++ b/drivers/media/dvb/dvb-core/dvb_frontend.c
@@ -870,6 +870,7 @@ dvb_register_frontend (int (*ioctl) (struct dvb_frontend *frontend,
 	static const struct dvb_device dvbdev_template = {
 		.users = ~0,
 		.writers = 1,
+		.readers = (~0)-1,
 		.fops = &dvb_frontend_fops,
 		.kernel_ioctl = dvb_frontend_ioctl
 	};
diff --git a/drivers/media/dvb/dvb-core/dvbdev.c b/drivers/media/dvb/dvb-core/dvbdev.c
index 77ee97465c78..22dcdcb7dc05 100644
--- a/drivers/media/dvb/dvb-core/dvbdev.c
+++ b/drivers/media/dvb/dvb-core/dvbdev.c
@@ -112,7 +112,11 @@ int dvb_generic_open(struct inode *inode, struct file *file)
 	if (!dvbdev->users)
                 return -EBUSY;
 
-	if ((file->f_flags & O_ACCMODE) != O_RDONLY) {
+	if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
+                if (!dvbdev->readers)
+		        return -EBUSY;
+		dvbdev->readers--;
+	} else {
                 if (!dvbdev->writers)
 		        return -EBUSY;
 		dvbdev->writers--;
@@ -130,8 +134,11 @@ int dvb_generic_release(struct inode *inode, struct file *file)
 	if (!dvbdev)
                 return -ENODEV;
 
-	if ((file->f_flags & O_ACCMODE) != O_RDONLY)
+	if ((file->f_flags & O_ACCMODE) == O_RDONLY) {
+		dvbdev->readers++;
+	} else {
 		dvbdev->writers++;
+	}
 
 	dvbdev->users++;
 	return 0;
diff --git a/drivers/media/dvb/dvb-core/dvbdev.h b/drivers/media/dvb/dvb-core/dvbdev.h
index 137a8dd4d042..92963f90f359 100644
--- a/drivers/media/dvb/dvb-core/dvbdev.h
+++ b/drivers/media/dvb/dvb-core/dvbdev.h
@@ -55,12 +55,18 @@ struct dvb_adapter {
 struct dvb_device {
 	struct list_head list_head;
 	struct file_operations *fops;
+ 
+ 
+ 
 	struct dvb_adapter *adapter;
 	int type;
 	u32 id;
 
-	int users;
+	/* in theory, 'users' can vanish now,
+	   but I don't want to change too much now... */
+	int readers;
 	int writers;
+	int users;
 
         /* don't really need those !? -- FIXME: use video_usercopy  */
         int (*kernel_ioctl)(struct inode *inode, struct file *file,
-- 
2.30.9