[PATCH v4 2/9] usb: musb: Add quirk to avoid skb reserve in gadget mode

[Peter Ujfalusi]

For tusb6010 the DMA functionality only possible if the buffer is 32bit
aligned (SYNC access to FIFO) since with ASYNC access the TX/RX offset
registers will corrupt eventually.
The MUSB_G_NO_SKB_RESERVE will set the quirk_avoids_skb_reserve flag in
usb_gadget struct to provide correctly aligned buffer.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
Tested-by: Tony Lindgren <tony@xxxxxxxxxxx>
---
 drivers/usb/musb/musb_core.c | 3 +++
 drivers/usb/musb/musb_core.h | 1 +
 2 files changed, 4 insertions(+)

diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
index 870da18f5077..87cbd56cc761 100644
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -2224,6 +2224,9 @@ musb_init_controller(struct device *dev, int nIrq, void __iomem *ctrl)
 		musb->io.ep_select = musb_flat_ep_select;
 	}
 
+	if (musb->io.quirks & MUSB_G_NO_SKB_RESERVE)
+		musb->g.quirk_avoids_skb_reserve = 1;
+
 	/* At least tusb6010 has its own offsets */
 	if (musb->ops->ep_offset)
 		musb->io.ep_offset = musb->ops->ep_offset;
diff --git a/drivers/usb/musb/musb_core.h b/drivers/usb/musb/musb_core.h
index 3e98d4268a64..9f22c5b8ce37 100644
--- a/drivers/usb/musb/musb_core.h
+++ b/drivers/usb/musb/musb_core.h
@@ -172,6 +172,7 @@ struct musb_io;
  */
 struct musb_platform_ops {
 
+#define MUSB_G_NO_SKB_RESERVE	BIT(9)
 #define MUSB_DA8XX		BIT(8)
 #define MUSB_PRESERVE_SESSION	BIT(7)
 #define MUSB_DMA_UX500		BIT(6)
-- 
2.13.0