[v2] usb: gadget: f_fs: Add compat_ioctl to ep0

[v2] usb: gadget: f_fs: Add compat_ioctl to ep0

[Jerry Zhang]

Functionfs ep0 ioctls can be handled in the
same way as a normal ioctl. Don't handle
underlying gadget ioctls since we don't know
whether they work with compat.

Signed-off-by: Jerry Zhang <zhangjerry@google.com>
---
 v2 - fixed error, realized gadget_ops doesn't have compat_ioctl

 drivers/usb/gadget/function/f_fs.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index 34d80cc2b667..8c6ed79f451d 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -641,6 +641,21 @@ static long ffs_ep0_ioctl(struct file *file, unsigned code, unsigned long value)
 	return ret;
 }
 
+#ifdef CONFIG_COMPAT
+static long ffs_ep0_compat_ioctl(struct file *file, unsigned code, unsigned long value)
+{
+	long ret;
+
+	if (code == FUNCTIONFS_INTERFACE_REVMAP) {
+		ret = ffs_ep0_ioctl(file, code, value);
+	} else {
+		ret = -ENOTTY;
+	}
+
+	return ret;
+}
+#endif
+
 static __poll_t ffs_ep0_poll(struct file *file, poll_table *wait)
 {
 	struct ffs_data *ffs = file->private_data;
@@ -691,6 +706,9 @@ static const struct file_operations ffs_ep0_operations = {
 	.release =	ffs_ep0_release,
 	.unlocked_ioctl =	ffs_ep0_ioctl,
 	.poll =		ffs_ep0_poll,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl = ffs_ep0_compat_ioctl,
+#endif
 };