[054/118] USB: ftdi_sio: enable two UART ports on ST Microconnect Lite

Ben Hutchings
2013-05-10T14:34:05Z

From: Adrian Thomasset <adrian.thomasset@st.com>

commit 71d9a2b95fc9c9474d46d764336efd7a5a805555 upstream.

The FT4232H used in the ST Micro Connect Lite has four hi-speed UART ports.
The first two ports are reserved for the JTAG interface.

We enable by default ports 2 and 3 as UARTs (where port 2 is a
conventional RS-232 UART)

Signed-off-by: Adrian Thomasset <adrian.thomasset@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/usb/serial/ftdi_sio.c | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)

--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -1819,8 +1819,11 @@ static int ftdi_8u2232c_probe(struct usb
}

/*
- * First and second port on STMCLiteadaptors is reserved for JTAG interface
- * and the forth port for pio
+ * First two ports on JTAG adaptors using an FT4232 such as STMicroelectronics's
+ * ST Micro Connect Lite are reserved for JTAG or other non-UART interfaces and
+ * can be accessed from userspace.
+ * The next two ports are enabled as UARTs by default, where port 2 is
+ * a conventional RS-232 UART.
*/
static int ftdi_stmclite_probe(struct usb_serial *serial)
{
@@ -1829,12 +1832,13 @@ static int ftdi_stmclite_probe(struct us

dbg("%s", __func__);

- if (interface == udev->actconfig->interface[2])
- return 0;
+ if (interface == udev->actconfig->interface[0] ||
+ interface == udev->actconfig->interface[1]) {
+ dev_info(&udev->dev, "Ignoring serial port reserved for JTAG\n");
+ return -ENODEV;
+ }

- dev_info(&udev->dev, "Ignoring serial port reserved for JTAG\n");
-
- return -ENODEV;
+ return 0;
}

/*