From: Felipe Balbi <balbi@ti.com>
Date: Thu, 15 Dec 2011 11:31:48 +0000 (+0200)
Subject: usb: gadget: add generic map/unmap request utilities
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=a698908d3b3be915ac20cd37faeff1216f6b4fe8;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

usb: gadget: add generic map/unmap request utilities

such utilities are currently duplicated on all UDC
drivers basically with the same structure. Let's group
all implementations into one generic implementation
and get rid of that duplication.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---

diff --git a/drivers/usb/gadget/udc-core.c b/drivers/usb/gadget/udc-core.c
index 0b0d12ccc487..56da49f31d6c 100644
--- a/drivers/usb/gadget/udc-core.c
+++ b/drivers/usb/gadget/udc-core.c
@@ -22,6 +22,7 @@
 #include <linux/device.h>
 #include <linux/list.h>
 #include <linux/err.h>
+#include <linux/dma-mapping.h>
 
 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.h>
@@ -49,6 +50,57 @@ static DEFINE_MUTEX(udc_lock);
 
 /* ------------------------------------------------------------------------- */
 
+int usb_gadget_map_request(struct usb_gadget *gadget,
+		struct usb_request *req, int is_in)
+{
+	if (req->length == 0)
+		return 0;
+
+	if (req->num_sgs) {
+		int     mapped;
+
+		mapped = dma_map_sg(&gadget->dev, req->sg, req->num_sgs,
+				is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
+		if (mapped == 0) {
+			dev_err(&gadget->dev, "failed to map SGs\n");
+			return -EFAULT;
+		}
+
+		req->num_mapped_sgs = mapped;
+	} else {
+		req->dma = dma_map_single(&gadget->dev, req->buf, req->length,
+				is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
+
+		if (dma_mapping_error(&gadget->dev, req->dma)) {
+			dev_err(&gadget->dev, "failed to map buffer\n");
+			return -EFAULT;
+		}
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(usb_gadget_map_request);
+
+void usb_gadget_unmap_request(struct usb_gadget *gadget,
+		struct usb_request *req, int is_in)
+{
+	if (req->length == 0)
+		return;
+
+	if (req->num_mapped_sgs) {
+		dma_unmap_sg(&gadget->dev, req->sg, req->num_mapped_sgs,
+				is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
+
+		req->num_mapped_sgs = 0;
+	} else {
+		dma_unmap_single(&gadget->dev, req->dma, req->length,
+				is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
+	}
+}
+EXPORT_SYMBOL_GPL(usb_gadget_unmap_request);
+
+/* ------------------------------------------------------------------------- */
+
 /**
  * usb_gadget_start - tells usb device controller to start up
  * @gadget: The gadget we want to get started
diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index da653b5c7134..9517466ababb 100644
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -950,6 +950,16 @@ static inline void usb_free_descriptors(struct usb_descriptor_header **v)
 
 /*-------------------------------------------------------------------------*/
 
+/* utility to simplify map/unmap of usb_requests to/from DMA */
+
+extern int usb_gadget_map_request(struct usb_gadget *gadget,
+		struct usb_request *req, int is_in);
+
+extern void usb_gadget_unmap_request(struct usb_gadget *gadget,
+		struct usb_request *req, int is_in);
+
+/*-------------------------------------------------------------------------*/
+
 /* utility wrapping a simple endpoint selection policy */
 
 extern struct usb_ep *usb_ep_autoconfig(struct usb_gadget *,