1 files changed, 40 insertions, 26 deletions

diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index 9ced8937a8f3..ce0d7b0db012 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -33,7 +33,6 @@
 
 #include <linux/kernel.h>
 #include <linux/errno.h>
-#include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/tty.h>
 #include <linux/tty_driver.h>
@@ -145,7 +144,7 @@ static struct ftdi_sio_quirk ftdi_8u2232c_quirk = {
  * Device ID not listed? Test it using
  * /sys/bus/usb-serial/drivers/ftdi_sio/new_id and send a patch or report.
  */
-static struct usb_device_id id_table_combined [] = {
+static const struct usb_device_id id_table_combined[] = {
 	{ USB_DEVICE(FTDI_VID, FTDI_ZEITCONTROL_TAGTRACE_MIFARE_PID) },
 	{ USB_DEVICE(FTDI_VID, FTDI_CTI_MINI_PID) },
 	{ USB_DEVICE(FTDI_VID, FTDI_CTI_NANO_PID) },
@@ -1695,11 +1694,8 @@ static int ftdi_sio_port_probe(struct usb_serial_port *port)
 
 
 	priv = kzalloc(sizeof(struct ftdi_private), GFP_KERNEL);
-	if (!priv) {
-		dev_err(&port->dev, "%s- kmalloc(%Zd) failed.\n", __func__,
-					sizeof(struct ftdi_private));
+	if (!priv)
 		return -ENOMEM;
-	}
 
 	mutex_init(&priv->cfg_lock);
 
@@ -2123,6 +2119,30 @@ static void ftdi_set_termios(struct tty_struct *tty,
 		termios->c_cflag |= CRTSCTS;
 	}
 
+	/*
+	 * All FTDI UART chips are limited to CS7/8. We shouldn't pretend to
+	 * support CS5/6 and revert the CSIZE setting instead.
+	 *
+	 * CS5 however is used to control some smartcard readers which abuse
+	 * this limitation to switch modes. Original FTDI chips fall back to
+	 * eight data bits.
+	 *
+	 * TODO: Implement a quirk to only allow this with mentioned
+	 *       readers. One I know of (Argolis Smartreader V1)
+	 *       returns "USB smartcard server" as iInterface string.
+	 *       The vendor didn't bother with a custom VID/PID of
+	 *       course.
+	 */
+	if (C_CSIZE(tty) == CS6) {
+		dev_warn(ddev, "requested CSIZE setting not supported\n");
+
+		termios->c_cflag &= ~CSIZE;
+		if (old_termios)
+			termios->c_cflag |= old_termios->c_cflag & CSIZE;
+		else
+			termios->c_cflag |= CS8;
+	}
+
 	cflag = termios->c_cflag;
 
 	if (!old_termios)
@@ -2159,19 +2179,19 @@ no_skip:
 	} else {
 		urb_value |= FTDI_SIO_SET_DATA_PARITY_NONE;
 	}
-	if (cflag & CSIZE) {
-		switch (cflag & CSIZE) {
-		case CS7:
-			urb_value |= 7;
-			dev_dbg(ddev, "Setting CS7\n");
-			break;
-		case CS8:
-			urb_value |= 8;
-			dev_dbg(ddev, "Setting CS8\n");
-			break;
-		default:
-			dev_err(ddev, "CSIZE was set but not CS7-CS8\n");
-		}
+	switch (cflag & CSIZE) {
+	case CS5:
+		dev_dbg(ddev, "Setting CS5 quirk\n");
+		break;
+	case CS7:
+		urb_value |= 7;
+		dev_dbg(ddev, "Setting CS7\n");
+		break;
+	default:
+	case CS8:
+		urb_value |= 8;
+		dev_dbg(ddev, "Setting CS8\n");
+		break;
 	}
 
 	/* This is needed by the break command since it uses the same command
@@ -2372,8 +2392,6 @@ static int ftdi_ioctl(struct tty_struct *tty,
 {
 	struct usb_serial_port *port = tty->driver_data;
 
-	dev_dbg(&port->dev, "%s cmd 0x%04x\n", __func__, cmd);
-
 	/* Based on code from acm.c and others */
 	switch (cmd) {
 
@@ -2390,11 +2408,7 @@ static int ftdi_ioctl(struct tty_struct *tty,
 	default:
 		break;
 	}
-	/* This is not necessarily an error - turns out the higher layers
-	 * will do some ioctls themselves (see comment above)
-	 */
-	dev_dbg(&port->dev, "%s arg not supported - it was 0x%04x - check /usr/include/asm/ioctls.h\n",
-		__func__, cmd);
+
 	return -ENOIOCTLCMD;
 }