On Tue, Jun 25, 2019 at 11:44 AM David Laight [off-list ref] wrote:

From: Dmitry Torokhov

quoted

Sent: 23 June 2019 07:32

Instead of doing conversion by hand, let's use the proper accessors.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/touchscreen/edt-ft5x06.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/input/touchscreen/edt-ft5x06.c b/drivers/input/touchscreen/edt-ft5x06.c
index c639ebce914c..ec770226e119 100644
--- a/drivers/input/touchscreen/edt-ft5x06.c
+++ b/drivers/input/touchscreen/edt-ft5x06.c

@@ -27,6 +27,7 @@
 #include <linux/gpio/consumer.h>
 #include <linux/input/mt.h>
 #include <linux/input/touchscreen.h>
+#include <asm/unaligned.h>

 #define WORK_REGISTER_THRESHOLD              0x00
 #define WORK_REGISTER_REPORT_RATE    0x08

@@ -239,8 +240,8 @@ static irqreturn_t edt_ft5x06_ts_isr(int irq, void *dev_id)
              if (tsdata->version == EDT_M06 && type == TOUCH_EVENT_DOWN)
                      continue;

-             x = ((buf[0] << 8) | buf[1]) & 0x0fff;
-             y = ((buf[2] << 8) | buf[3]) & 0x0fff;
+             x = get_unaligned_be16(buf) & 0x0fff;
+             y = get_unaligned_be16(buf + 2) & 0x0fff;

You might as well delete the pointless masking with 0xff.

Hmm... Does it guarantee the most significant nibble to be always 0?
(Note 16-bit value and three f:s in the mask)


-- 
With Best Regards,
Andy Shevchenko