Input: edt-ft5x06 - unify the crc check

With this patch, the CRC is always verified by the same function, even in
the case of accessing registers where the number of bytes is minimal.

Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Link: https://lore.kernel.org/r/20230402200951.1032513-9-dario.binacchi@amarulasolutions.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/drivers/input/touchscreen/edt-ft5x06.c b/drivers/input/touchscreen/edt-ft5x06.c
index 8aae4c1e6b737451866d33fc3843457c609709c5..fdb32e3591be9806c7771394cf6030aa5574f7be 100644 (file)
--- a/drivers/input/touchscreen/edt-ft5x06.c
+++ b/drivers/input/touchscreen/edt-ft5x06.c
@@ -240,13 +240,10 @@ static int edt_M06_i2c_read(void *context, const void *reg_buf, size_t reg_size,
                if (!edt_ft5x06_ts_check_crc(tsdata, val_buf, val_size))
                        return -EIO;
        } else if (reg_read) {
-               u8 crc = wbuf[0] ^ wbuf[1] ^ rbuf[0];
-
-               if (crc != rbuf[1]) {
-                       dev_err(dev, "crc error: 0x%02x expected, got 0x%02x\n",
-                               crc, rbuf[1]);
+               wbuf[2] = rbuf[0];
+               wbuf[3] = rbuf[1];
+               if (!edt_ft5x06_ts_check_crc(tsdata, wbuf, 4))
                        return -EIO;
-               }
 
                *((u8 *)val_buf) = rbuf[0];
        }