arch/risc-v/src/mpfs/mpfs_serial.c: Correct setting of nbits

Number of bits was set wrongly in TCSETS for mpfs

Signed-off-by: Jukka Laitinen <jukkax@ssrc.tii.ae>

arch/risc-v/src/mpfs/mpfs_serial.c

@@ -907,11 +907,32 @@ static int up_ioctl(struct file *filep, int cmd, unsigned long arg)
 
         priv->stopbits2 = (termiosp->c_cflag & CSTOPB) != 0;
 
-        priv->bits = (termiosp->c_cflag & CS5) ? 5 : 0;
+        switch (termiosp->c_cflag & CSIZE)
-        priv->bits = (termiosp->c_cflag & CS6) ? 6 : 0;
+          {
-        priv->bits = (termiosp->c_cflag & CS7) ? 7 : 0;
+          case CS5:
-        priv->bits = (termiosp->c_cflag & CS8) ? 8 : 0;
+            priv->bits = 5;
+            break;
 
+          case CS6:
+            priv->bits = 6;
+            break;
+
+          case CS7:
+            priv->bits = 7;
+            break;
+
+          case CS8:
+            priv->bits = 8;
+            break;
+
+          default:
+            priv->bits = 0;
+            ret = -EINVAL;
+            break;
+          }
+
+        if (ret == OK)
+          {
             /* Note that only cfgetispeed is used because we have knowledge
              * that only one speed is supported.
              */
@@ -924,6 +945,7 @@ static int up_ioctl(struct file *filep, int cmd, unsigned long arg)
 
             up_set_format(dev);
           }
+      }
       break;
 #endif /* CONFIG_SERIAL_TERMIOS */