usb: musb: gadget: fix dma length in txstate

DMA length should not go beyond the availabe space
of request buffer, so fix it.

Also set max_len of cppi dma channel as max size of
int type, so make musb dma handling happier.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Anand Gadiyar <gadiyar@ti.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/musb/cppi_dma.c

@@ -322,6 +322,7 @@ cppi_channel_allocate(struct dma_controller *c,
 				index, transmit ? 'T' : 'R', cppi_ch);
 	cppi_ch->hw_ep = ep;
 	cppi_ch->channel.status = MUSB_DMA_STATUS_FREE;
+	cppi_ch->channel.max_len = 0x7fffffff;
 
 	DBG(4, "Allocate CPPI%d %cX\n", index, transmit ? 'T' : 'R');
 	return &cppi_ch->channel;

drivers/usb/musb/musb_gadget.c

@@ -300,6 +300,11 @@ static void txstate(struct musb *musb, struct musb_request *req)
 #ifndef	CONFIG_MUSB_PIO_ONLY
 	if (is_dma_capable() && musb_ep->dma) {
 		struct dma_controller	*c = musb->dma_controller;
+		size_t request_size;
+
+		/* setup DMA, then program endpoint CSR */
+		request_size = min_t(size_t, request->length - request->actual,
+					musb_ep->dma->max_len);
 
 		use_dma = (request->dma != DMA_ADDR_INVALID);
 
@@ -307,11 +312,6 @@ static void txstate(struct musb *musb, struct musb_request *req)
 
 #ifdef CONFIG_USB_INVENTRA_DMA
 		{
-			size_t request_size;
-
-			/* setup DMA, then program endpoint CSR */
-			request_size = min_t(size_t, request->length,
-						musb_ep->dma->max_len);
 			if (request_size < musb_ep->packet_sz)
 				musb_ep->dma->desired_mode = 0;
 			else
@@ -373,8 +373,8 @@ static void txstate(struct musb *musb, struct musb_request *req)
 		use_dma = use_dma && c->channel_program(
 				musb_ep->dma, musb_ep->packet_sz,
 				0,
-				request->dma,
-				request->length);
+				request->dma + request->actual,
+				request_size);
 		if (!use_dma) {
 			c->channel_release(musb_ep->dma);
 			musb_ep->dma = NULL;
@@ -386,8 +386,8 @@ static void txstate(struct musb *musb, struct musb_request *req)
 		use_dma = use_dma && c->channel_program(
 				musb_ep->dma, musb_ep->packet_sz,
 				request->zero,
-				request->dma,
-				request->length);
+				request->dma + request->actual,
+				request_size);
 #endif
 	}
 #endif