usb: gadget: fix usb_ep_align_maybe endianness and new usb_ep_align

[ Upstream commit 16b114a6d7973cf027e4c2b23eae1076eaf98c25 ]

USB spec specifies wMaxPacketSize to be little endian (as other properties),
so when using this variable in the driver we should convert to the current
CPU endianness if necessary.

This patch also introduces usb_ep_align() which does always returns the
aligned buffer size for an endpoint. This is useful to be used by USB requests
allocator functions.

Signed-off-by: Felipe F. Tonello <eu@felipetonello.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>

diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index 4f3dfb7d065420d012eeade7154575100473602c..96a8870e38fe120aa88d8c32f4bd9a0f6c442e2b 100644 (file)
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -585,9 +585,21 @@ static inline struct usb_gadget *dev_to_usb_gadget(struct device *dev)
        list_for_each_entry(tmp, &(gadget)->ep_list, ep_list)
 
 
+/**
+ * usb_ep_align - returns @len aligned to ep's maxpacketsize.
+ * @ep: the endpoint whose maxpacketsize is used to align @len
+ * @len: buffer size's length to align to @ep's maxpacketsize
+ *
+ * This helper is used to align buffer's size to an ep's maxpacketsize.
+ */
+static inline size_t usb_ep_align(struct usb_ep *ep, size_t len)
+{
+       return round_up(len, (size_t)le16_to_cpu(ep->desc->wMaxPacketSize));
+}
+
 /**
  * usb_ep_align_maybe - returns @len aligned to ep's maxpacketsize if gadget
- *     requires quirk_ep_out_aligned_size, otherwise reguens len.
+ *     requires quirk_ep_out_aligned_size, otherwise returns len.
  * @g: controller to check for quirk
  * @ep: the endpoint whose maxpacketsize is used to align @len
  * @len: buffer size's length to align to @ep's maxpacketsize
@@ -598,8 +610,7 @@ static inline struct usb_gadget *dev_to_usb_gadget(struct device *dev)
 static inline size_t
 usb_ep_align_maybe(struct usb_gadget *g, struct usb_ep *ep, size_t len)
 {
-       return !g->quirk_ep_out_aligned_size ? len :
-                       round_up(len, (size_t)ep->desc->wMaxPacketSize);
+       return g->quirk_ep_out_aligned_size ? usb_ep_align(ep, len) : len;
 }
 
 /**