Input: usbtouchscreen - reduce number fo be16_to_cpu conversions

Let's perform be16_to_cpu() conversions once for each received packet,
and then use cached values. Makes code a little bit easier to follow.

Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

diff --git a/drivers/input/touchscreen/usbtouchscreen.c b/drivers/input/touchscreen/usbtouchscreen.c
index 567d57215c28e14bbe78621d1add3b2d1204ff2f..5d6bf2a4bbad28e10ddb0cd463d1d3f4c36d4c1c 100644 (file)
--- a/drivers/input/touchscreen/usbtouchscreen.c
+++ b/drivers/input/touchscreen/usbtouchscreen.c
@@ -849,29 +849,32 @@ static void nexio_exit(struct usbtouch_usb *usbtouch)
 
 static int nexio_read_data(struct usbtouch_usb *usbtouch, unsigned char *pkt)
 {
-       int x, y, begin_x, begin_y, end_x, end_y, w, h, ret;
        struct nexio_touch_packet *packet = (void *) pkt;
        struct nexio_priv *priv = usbtouch->priv;
+       unsigned int data_len = be16_to_cpu(packet->data_len);
+       unsigned int x_len = be16_to_cpu(packet->x_len);
+       unsigned int y_len = be16_to_cpu(packet->y_len);
+       int x, y, begin_x, begin_y, end_x, end_y, w, h, ret;
 
        /* got touch data? */
        if ((pkt[0] & 0xe0) != 0xe0)
                return 0;
 
-       if (be16_to_cpu(packet->data_len) > 0xff)
-               packet->data_len = cpu_to_be16(be16_to_cpu(packet->data_len) - 0x100);
-       if (be16_to_cpu(packet->x_len) > 0xff)
-               packet->x_len = cpu_to_be16(be16_to_cpu(packet->x_len) - 0x80);
+       if (data_len > 0xff)
+               data_len -= 0x100;
+       if (x_len > 0xff)
+               x_len -= 0x80;
 
        /* send ACK */
        ret = usb_submit_urb(priv->ack, GFP_ATOMIC);
 
        if (!usbtouch->type->max_xc) {
-               usbtouch->type->max_xc = 2 * be16_to_cpu(packet->x_len);
-               input_set_abs_params(usbtouch->input, ABS_X, 0,
-                                    2 * be16_to_cpu(packet->x_len), 0, 0);
-               usbtouch->type->max_yc = 2 * be16_to_cpu(packet->y_len);
-               input_set_abs_params(usbtouch->input, ABS_Y, 0,
-                                    2 * be16_to_cpu(packet->y_len), 0, 0);
+               usbtouch->type->max_xc = 2 * x_len;
+               input_set_abs_params(usbtouch->input, ABS_X,
+                                    0, usbtouch->type->max_xc, 0, 0);
+               usbtouch->type->max_yc = 2 * y_len;
+               input_set_abs_params(usbtouch->input, ABS_Y,
+                                    0, usbtouch->type->max_yc, 0, 0);
        }
        /*
         * The device reports state of IR sensors on X and Y axes.
@@ -881,22 +884,21 @@ static int nexio_read_data(struct usbtouch_usb *usbtouch, unsigned char *pkt)
         * it's disabled (and untested) here as there's no X driver for that.
         */
        begin_x = end_x = begin_y = end_y = -1;
-       for (x = 0; x < be16_to_cpu(packet->x_len); x++) {
+       for (x = 0; x < x_len; x++) {
                if (begin_x == -1 && packet->data[x] > NEXIO_THRESHOLD) {
                        begin_x = x;
                        continue;
                }
                if (end_x == -1 && begin_x != -1 && packet->data[x] < NEXIO_THRESHOLD) {
                        end_x = x - 1;
-                       for (y = be16_to_cpu(packet->x_len);
-                            y < be16_to_cpu(packet->data_len); y++) {
+                       for (y = x_len; y < data_len; y++) {
                                if (begin_y == -1 && packet->data[y] > NEXIO_THRESHOLD) {
-                                       begin_y = y - be16_to_cpu(packet->x_len);
+                                       begin_y = y - x_len;
                                        continue;
                                }
                                if (end_y == -1 &&
                                    begin_y != -1 && packet->data[y] < NEXIO_THRESHOLD) {
-                                       end_y = y - 1 - be16_to_cpu(packet->x_len);
+                                       end_y = y - 1 - x_len;
                                        w = end_x - begin_x;
                                        h = end_y - begin_y;
 #if 0