3 files changed, 209 insertions, 29 deletions

diff --git a/drivers/usb/host/ohci-dbg.c b/drivers/usb/host/ohci-dbg.c
index 9bd589806245..a22c30aa745d 100644
--- a/drivers/usb/host/ohci-dbg.c
+++ b/drivers/usb/host/ohci-dbg.c
@@ -401,6 +401,42 @@ static inline void remove_debug_files (struct ohci_hcd *bus) { }
 
 #else
 
+static int debug_async_open(struct inode *, struct file *);
+static int debug_periodic_open(struct inode *, struct file *);
+static int debug_registers_open(struct inode *, struct file *);
+static int debug_async_open(struct inode *, struct file *);
+static ssize_t debug_output(struct file*, char __user*, size_t, loff_t*);
+static int debug_close(struct inode *, struct file *);
+
+static const struct file_operations debug_async_fops = {
+        .owner          = THIS_MODULE,
+        .open           = debug_async_open,
+        .read           = debug_output,
+        .release        = debug_close,
+};
+static const struct file_operations debug_periodic_fops = {
+        .owner          = THIS_MODULE,
+        .open           = debug_periodic_open,
+        .read           = debug_output,
+        .release        = debug_close,
+};
+static const struct file_operations debug_registers_fops = {
+        .owner          = THIS_MODULE,
+        .open           = debug_registers_open,
+        .read           = debug_output,
+        .release        = debug_close,
+};
+
+static struct dentry *ohci_debug_root;
+
+struct debug_buffer {
+        ssize_t (*fill_func)(struct debug_buffer *);    /* fill method */
+        struct device *dev;
+        struct mutex mutex;     /* protect filling of buffer */
+        size_t count;           /* number of characters filled into buffer */
+        char *page;
+};
+
 static ssize_t
 show_list (struct ohci_hcd *ohci, char *buf, size_t count, struct ed *ed)
 {
@@ -467,8 +503,7 @@ show_list (struct ohci_hcd *ohci, char *buf, size_t count, struct ed *ed)
         return count - size;
 }
 
-static ssize_t
-show_async(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t fill_async_buffer(struct debug_buffer *buf)
 {
         struct usb_bus          *bus;
         struct usb_hcd          *hcd;
@@ -476,25 +511,23 @@ show_async(struct device *dev, struct device_attribute *attr, char *buf)
         size_t                  temp;
         unsigned long           flags;
 
-        bus = dev_get_drvdata(dev);
+        bus = dev_get_drvdata(buf->dev);
         hcd = bus_to_hcd(bus);
         ohci = hcd_to_ohci(hcd);
 
         /* display control and bulk lists together, for simplicity */
         spin_lock_irqsave (&ohci->lock, flags);
-        temp = show_list (ohci, buf, PAGE_SIZE, ohci->ed_controltail);
-        temp += show_list (ohci, buf + temp, PAGE_SIZE - temp, ohci->ed_bulktail);
+        temp = show_list(ohci, buf->page, buf->count, ohci->ed_controltail);
+        temp += show_list(ohci, buf->page + temp, buf->count - temp,
+                          ohci->ed_bulktail);
         spin_unlock_irqrestore (&ohci->lock, flags);
 
         return temp;
 }
-static DEVICE_ATTR(async, S_IRUGO, show_async, NULL);
-
 
 #define DBG_SCHED_LIMIT 64
 
-static ssize_t
-show_periodic(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t fill_periodic_buffer(struct debug_buffer *buf)
 {
         struct usb_bus          *bus;
         struct usb_hcd          *hcd;
@@ -509,10 +542,10 @@ show_periodic(struct device *dev, struct device_attribute *attr, char *buf)
                 return 0;
         seen_count = 0;
 
-        bus = dev_get_drvdata(dev);
+        bus = (struct usb_bus *)dev_get_drvdata(buf->dev);
         hcd = bus_to_hcd(bus);
         ohci = hcd_to_ohci(hcd);
-        next = buf;
+        next = buf->page;
         size = PAGE_SIZE;
 
         temp = scnprintf (next, size, "size = %d\n", NUM_INTS);
@@ -589,13 +622,9 @@ show_periodic(struct device *dev, struct device_attribute *attr, char *buf)
 
         return PAGE_SIZE - size;
 }
-static DEVICE_ATTR(periodic, S_IRUGO, show_periodic, NULL);
-
-
 #undef DBG_SCHED_LIMIT
 
-static ssize_t
-show_registers(struct device *dev, struct device_attribute *attr, char *buf)
+static ssize_t fill_registers_buffer(struct debug_buffer *buf)
 {
         struct usb_bus          *bus;
         struct usb_hcd          *hcd;
@@ -606,11 +635,11 @@ show_registers(struct device *dev, struct device_attribute *attr, char *buf)
         char                    *next;
         u32                     rdata;
 
-        bus = dev_get_drvdata(dev);
+        bus = (struct usb_bus *)dev_get_drvdata(buf->dev);
         hcd = bus_to_hcd(bus);
         ohci = hcd_to_ohci(hcd);
         regs = ohci->regs;
-        next = buf;
+        next = buf->page;
         size = PAGE_SIZE;
 
         spin_lock_irqsave (&ohci->lock, flags);
@@ -677,29 +706,155 @@ show_registers(struct device *dev, struct device_attribute *attr, char *buf)
 
 done:
         spin_unlock_irqrestore (&ohci->lock, flags);
+
         return PAGE_SIZE - size;
 }
-static DEVICE_ATTR(registers, S_IRUGO, show_registers, NULL);
 
+static struct debug_buffer *alloc_buffer(struct device *dev,
+                                ssize_t (*fill_func)(struct debug_buffer *))
+{
+        struct debug_buffer *buf;
+
+        buf = kzalloc(sizeof(struct debug_buffer), GFP_KERNEL);
 
+        if (buf) {
+                buf->dev = dev;
+                buf->fill_func = fill_func;
+                mutex_init(&buf->mutex);
+        }
+
+        return buf;
+}
+
+static int fill_buffer(struct debug_buffer *buf)
+{
+        int ret = 0;
+
+        if (!buf->page)
+                buf->page = (char *)get_zeroed_page(GFP_KERNEL);
+
+        if (!buf->page) {
+                ret = -ENOMEM;
+                goto out;
+        }
+
+        ret = buf->fill_func(buf);
+
+        if (ret >= 0) {
+                buf->count = ret;
+                ret = 0;
+        }
+
+out:
+        return ret;
+}
+
+static ssize_t debug_output(struct file *file, char __user *user_buf,
+                        size_t len, loff_t *offset)
+{
+        struct debug_buffer *buf = file->private_data;
+        int ret = 0;
+
+        mutex_lock(&buf->mutex);
+        if (buf->count == 0) {
+                ret = fill_buffer(buf);
+                if (ret != 0) {
+                        mutex_unlock(&buf->mutex);
+                        goto out;
+                }
+        }
+        mutex_unlock(&buf->mutex);
+
+        ret = simple_read_from_buffer(user_buf, len, offset,
+                                      buf->page, buf->count);
+
+out:
+        return ret;
+
+}
+
+static int debug_close(struct inode *inode, struct file *file)
+{
+        struct debug_buffer *buf = file->private_data;
+
+        if (buf) {
+                if (buf->page)
+                        free_page((unsigned long)buf->page);
+                kfree(buf);
+        }
+
+        return 0;
+}
+static int debug_async_open(struct inode *inode, struct file *file)
+{
+        file->private_data = alloc_buffer(inode->i_private, fill_async_buffer);
+
+        return file->private_data ? 0 : -ENOMEM;
+}
+
+static int debug_periodic_open(struct inode *inode, struct file *file)
+{
+        file->private_data = alloc_buffer(inode->i_private,
+                                          fill_periodic_buffer);
+
+        return file->private_data ? 0 : -ENOMEM;
+}
+
+static int debug_registers_open(struct inode *inode, struct file *file)
+{
+        file->private_data = alloc_buffer(inode->i_private,
+                                          fill_registers_buffer);
+
+        return file->private_data ? 0 : -ENOMEM;
+}
 static inline void create_debug_files (struct ohci_hcd *ohci)
 {
-        struct device *dev = ohci_to_hcd(ohci)->self.dev;
-        int retval;
+        struct usb_bus *bus = &ohci_to_hcd(ohci)->self;
+        struct device *dev = bus->dev;
+
+        ohci->debug_dir = debugfs_create_dir(bus->bus_name, ohci_debug_root);
+        if (!ohci->debug_dir)
+                goto dir_error;
+
+        ohci->debug_async = debugfs_create_file("async", S_IRUGO,
+                                                ohci->debug_dir, dev,
+                                                &debug_async_fops);
+        if (!ohci->debug_async)
+                goto async_error;
+
+        ohci->debug_periodic = debugfs_create_file("periodic", S_IRUGO,
+                                                   ohci->debug_dir, dev,
+                                                   &debug_periodic_fops);
+        if (!ohci->debug_periodic)
+                goto periodic_error;
+
+        ohci->debug_registers = debugfs_create_file("registers", S_IRUGO,
+                                                    ohci->debug_dir, dev,
+                                                    &debug_registers_fops);
+        if (!ohci->debug_registers)
+                goto registers_error;
 
-        retval = device_create_file(dev, &dev_attr_async);
-        retval = device_create_file(dev, &dev_attr_periodic);
-        retval = device_create_file(dev, &dev_attr_registers);
         ohci_dbg (ohci, "created debug files\n");
+        return;
+
+registers_error:
+        debugfs_remove(ohci->debug_periodic);
+periodic_error:
+        debugfs_remove(ohci->debug_async);
+async_error:
+        debugfs_remove(ohci->debug_dir);
+dir_error:
+        ohci->debug_periodic = NULL;
+        ohci->debug_async = NULL;
+        ohci->debug_dir = NULL;
 }
 
 static inline void remove_debug_files (struct ohci_hcd *ohci)
 {
-        struct device *dev = ohci_to_hcd(ohci)->self.dev;
-
-        device_remove_file(dev, &dev_attr_async);
-        device_remove_file(dev, &dev_attr_periodic);
-        device_remove_file(dev, &dev_attr_registers);
+        debugfs_remove(ohci->debug_registers);
+        debugfs_remove(ohci->debug_periodic);
+        debugfs_remove(ohci->debug_async);
+        debugfs_remove(ohci->debug_dir);
 }
 
 #endif
diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c
index ddd4ee1f2413..baca09af6076 100644
--- a/drivers/usb/host/ohci-hcd.c
+++ b/drivers/usb/host/ohci-hcd.c
@@ -36,6 +36,7 @@
 #include <linux/dmapool.h>
 #include <linux/reboot.h>
 #include <linux/workqueue.h>
+#include <linux/debugfs.h>
 
 #include <asm/io.h>
 #include <asm/irq.h>
@@ -1068,6 +1069,14 @@ static int __init ohci_hcd_mod_init(void)
         pr_debug ("%s: block sizes: ed %Zd td %Zd\n", hcd_name,
                 sizeof (struct ed), sizeof (struct td));
 
+#ifdef DEBUG
+        ohci_debug_root = debugfs_create_dir("ohci", NULL);
+        if (!ohci_debug_root) {
+                retval = -ENOENT;
+                goto error_debug;
+        }
+#endif
+
 #ifdef PS3_SYSTEM_BUS_DRIVER
         retval = ps3_ohci_driver_register(&PS3_SYSTEM_BUS_DRIVER);
         if (retval < 0)
@@ -1130,6 +1139,12 @@ static int __init ohci_hcd_mod_init(void)
         ps3_ohci_driver_unregister(&PS3_SYSTEM_BUS_DRIVER);
  error_ps3:
 #endif
+#ifdef DEBUG
+        debugfs_remove(ohci_debug_root);
+        ohci_debug_root = NULL;
+ error_debug:
+#endif
+
         return retval;
 }
 module_init(ohci_hcd_mod_init);
@@ -1154,6 +1169,9 @@ static void __exit ohci_hcd_mod_exit(void)
 #ifdef PS3_SYSTEM_BUS_DRIVER
         ps3_ohci_driver_unregister(&PS3_SYSTEM_BUS_DRIVER);
 #endif
+#ifdef DEBUG
+        debugfs_remove(ohci_debug_root);
+#endif
 }
 module_exit(ohci_hcd_mod_exit);
 
diff --git a/drivers/usb/host/ohci.h b/drivers/usb/host/ohci.h
index 47c5c66a282c..dc544ddc7849 100644
--- a/drivers/usb/host/ohci.h
+++ b/drivers/usb/host/ohci.h
@@ -408,6 +408,13 @@ struct ohci_hcd {
         unsigned                eds_scheduled;
         struct ed               *ed_to_check;
         unsigned                zf_delay;
+
+#ifdef DEBUG
+        struct dentry           *debug_dir;
+        struct dentry           *debug_async;
+        struct dentry           *debug_periodic;
+        struct dentry           *debug_registers;
+#endif
 };
 
 #ifdef CONFIG_PCI