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>

1 files changed, 18 insertions, 16 deletions

diff --git a/drivers/input/touchscreen/usbtouchscreen.c b/drivers/input/touchscreen/usbtouchscreen.c
index 567d57215c28..5d6bf2a4bbad 100644
--- 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