rt2x00: Support for large vendor requests

Adds an extra rt2x00 vendor request function to support register
transfers beyond the CSR_CACHE_SIZE / USB packet size limit. This
is useful for firmware uploads, beacon templates and keys, all
of which are to large to do with a single USB request.
Signed-off-by: Iwo Mergler <Iwo@call-direct.com.au>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/rt2x00/rt2x00usb.c

@@ -122,6 +122,38 @@ int rt2x00usb_vendor_request_buff(struct rt2x00_dev *rt2x00dev,
 }
 EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request_buff);
 
+int rt2x00usb_vendor_request_large_buff(struct rt2x00_dev *rt2x00dev,
+					const u8 request, const u8 requesttype,
+					const u16 offset, void *buffer,
+					const u16 buffer_length,
+					const int timeout)
+{
+	int status = 0;
+	unsigned char *tb;
+	u16 off, len, bsize;
+
+	mutex_lock(&rt2x00dev->usb_cache_mutex);
+
+	tb  = buffer;
+	off = offset;
+	len = buffer_length;
+	while (len && !status) {
+		bsize = min_t(u16, CSR_CACHE_SIZE, len);
+		status = rt2x00usb_vendor_req_buff_lock(rt2x00dev, request,
+							requesttype, off, tb,
+							bsize, timeout);
+
+		tb  += bsize;
+		len -= bsize;
+		off += bsize;
+	}
+
+	mutex_unlock(&rt2x00dev->usb_cache_mutex);
+
+	return status;
+}
+EXPORT_SYMBOL_GPL(rt2x00usb_vendor_request_large_buff);
+
 /*
  * TX data handlers.
  */

drivers/net/wireless/rt2x00/rt2x00usb.h

@@ -70,7 +70,7 @@
 /*
  * Cache size
  */
-#define CSR_CACHE_SIZE			8
+#define CSR_CACHE_SIZE			64
 #define CSR_CACHE_SIZE_FIRMWARE		64
 
 /*
@@ -171,6 +171,25 @@ int rt2x00usb_vendor_req_buff_lock(struct rt2x00_dev *rt2x00dev,
 				   const u16 offset, void *buffer,
 				   const u16 buffer_length, const int timeout);
 
+/**
+ * rt2x00usb_vendor_request_large_buff - Send register command to device (buffered)
+ * @rt2x00dev: Pointer to &struct rt2x00_dev
+ * @request: USB vendor command (See &enum rt2x00usb_vendor_request)
+ * @requesttype: Request type &USB_VENDOR_REQUEST_*
+ * @offset: Register start offset to perform action on
+ * @buffer: Buffer where information will be read/written to by device
+ * @buffer_length: Size of &buffer
+ * @timeout: Operation timeout
+ *
+ * This function is used to transfer register data in blocks larger
+ * then CSR_CACHE_SIZE. Use for firmware upload, keys and beacons.
+ */
+int rt2x00usb_vendor_request_large_buff(struct rt2x00_dev *rt2x00dev,
+					const u8 request, const u8 requesttype,
+					const u16 offset, void *buffer,
+					const u16 buffer_length,
+					const int timeout);
+
 /**
  * rt2x00usb_vendor_request_sw - Send single register command to device
  * @rt2x00dev: Pointer to &struct rt2x00_dev