[PATCH v6 4/5] check quirk to pad epout buf size when not aligned to maxpacketsize

[David Cohen <david.a.cohen@linux.intel.com>]

From: Michal Nazarewicz <mina86@mina86.com>

Check gadget.quirk_ep_out_aligned_size to decide if buffer size requires
to be aligned to maxpacketsize of an out endpoint.  ffs_epfile_io() needs
to pad epout buffer to match above condition if quirk is found.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: David Cohen <david.a.cohen@linux.intel.com>
---
 drivers/usb/gadget/f_fs.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/f_fs.c b/drivers/usb/gadget/f_fs.c
index efa1152a4c15..688cfa005b4d 100644
--- a/drivers/usb/gadget/f_fs.c
+++ b/drivers/usb/gadget/f_fs.c
@@ -755,6 +755,7 @@ static ssize_t ffs_epfile_io(struct file *file,
 			     char __user *buf, size_t len, int read)
 {
 	struct ffs_epfile *epfile = file->private_data;
+	struct usb_gadget *gadget = epfile->ffs->gadget;
 	struct ffs_ep *ep;
 	char *data = NULL;
 	ssize_t ret;
@@ -790,7 +791,14 @@ static ssize_t ffs_epfile_io(struct file *file,
 
 	/* Allocate & copy */
 	if (!halt) {
-		data = kmalloc(len, GFP_KERNEL);
+		/*
+		 * Controller requires buffer size to be aligned to
+		 * maxpacketsize of an out endpoint.
+		 */
+		size_t data_len = read && gadget->quirk_ep_out_aligned_size ?
+			usb_ep_align_maxpacketsize(ep->ep, len) : len;
+
+		data = kmalloc(data_len, GFP_KERNEL);
 		if (unlikely(!data))
 			return -ENOMEM;
 
-- 
1.8.4.2