Commit 0b2d2bba authored by David Cohen's avatar David Cohen Committed by Felipe Balbi
Browse files

usb: gadget: add quirk_ep_out_aligned_size field to struct usb_gadget 



Due to USB controllers may have different restrictions, usb gadget layer
needs to provide a generic way to inform gadget functions to complain
with non-standard requirements.

This patch adds 'quirk_ep_out_aligned_size' field to struct usb_gadget
to inform when controller's epout requires buffer size to be aligned to
MaxPacketSize. A helper is also provided to align buffer size when
necessary.

Cc: Alan Stern <stern@rowland.harvard.edu>
Acked-by: default avatarMichal Nazarewicz <mina86@mina86.com>
Signed-off-by: default avatarDavid Cohen <david.a.cohen@linux.intel.com>
Signed-off-by: default avatarFelipe Balbi <balbi@ti.com>
parent d8318d7f

include/linux/usb/gadget.h

+20 −0
Original line number Diff line number Diff line
@@ -502,6 +502,8 @@ struct usb_gadget_ops { 
 *	only supports HNP on a different root port.

 * @b_hnp_enable: OTG device feature flag, indicating that the A-Host

 *	enabled HNP support.

 * @quirk_ep_out_aligned_size: epout requires buffer size to be aligned to

 *	MaxPacketSize.

 *

 * Gadgets have a mostly-portable "gadget driver" implementing device

 * functions, handling all usb configurations and interfaces.  Gadget
@@ -541,6 +543,7 @@ struct usb_gadget { 
	unsigned			b_hnp_enable:1;

	unsigned			a_hnp_support:1;

	unsigned			a_alt_hnp_support:1;

	unsigned			quirk_ep_out_aligned_size:1;

};

#define work_to_gadget(w)	(container_of((w), struct usb_gadget, work))
@@ -558,6 +561,23 @@ 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_maybe - returns @len aligned to ep's maxpacketsize if gadget

 *	requires quirk_ep_out_aligned_size, otherwise reguens 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

 *

 * This helper is used in case it's required for any reason to check and maybe

 * align buffer's size to an ep's maxpacketsize.

 */

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);

}



/**

 * gadget_is_dualspeed - return true iff the hardware handles high speed

 * @g: controller that might support both high and full speeds

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