diff mbox series

[5/5] USB: serial: ftdi_sio: add support for FreeCalypso DUART28C adapter

Message ID 20201130153742.9163-6-johan@kernel.org (mailing list archive)
State Superseded
Headers show
Series tty: add flag to suppress ready signalling on open | expand

Commit Message

Johan Hovold Nov. 30, 2020, 3:37 p.m. UTC 
From: "Mychaela N. Falconia" <falcon@freecalypso.org>

FreeCalypso DUART28C is an FT2232D-based USB to dual UART adapter
with a special quirk: Channel B RTS and DTR outputs (BDBUS2 and BDBUS4
on the chip) have been repurposed to drive PWON and RESET controls
on Calypso targets.  The circuit is wired such that BDBUS[24] high
(RTS/DTR inactive) is the normal state with Iota VRPC controls
NOT activated, whereas BDBUS[24] low (RTS or DTR active) turn ON
the corresponding open drain control signal drivers.

A special ftdi_sio driver quirk is needed in order to suppress
automatic assertion of DTR & RTS on device open: this device's
special PWON and RESET control drivers MUST NOT be activated
when the port is ordinarily opened for plain serial communication,
instead they must only be activated when a special userspace
application explicitly requests such activation with a TIOCMBIS ioctl.
These special userspace applications are responsible for making the
needed pulse with a TIOCMBIS, delay, TIOCMBIC sequence.

The special quirk is conditionalized on the DUART28C adapter's custom
USB ID, and is further limited to FT2232D Channel B only: Channel A
is wired normally, with the chip's ADBUS2 and ADBUS4 outputs
actually being RTS and DTR rather than something else.

Signed-off-by: Mychaela N. Falconia <falcon@freecalypso.org>
[johan: reimplement using new NORDY flag, trim quirk comment]
Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/usb/serial/ftdi_sio.c     | 22 ++++++++++++++++++++++
 drivers/usb/serial/ftdi_sio_ids.h |  1 +
 2 files changed, 23 insertions(+)

Comments

Jiri Slaby Dec. 1, 2020, 6:54 a.m. UTC | #1 
On 30. 11. 20, 16:37, Johan Hovold wrote:
> --- a/drivers/usb/serial/ftdi_sio.c
> +++ b/drivers/usb/serial/ftdi_sio.c
...
> @@ -2386,6 +2393,21 @@ static int ftdi_stmclite_probe(struct usb_serial *serial)
>   	return 0;
>   }
>   
> +/*
> + * FreeCalypso DUART28C is an FT2232D-based USB to dual UART adapter
> + * with a special quirk: Channel B RTS and DTR outputs (BDBUS2 and BDBUS4
> + * on the chip) have been repurposed to drive PWON and RESET controls.
> + */
> +static void ftdi_duart28c_setup(struct usb_serial_port *port)
> +{
> +	struct usb_serial *serial = port->serial;
> +	struct usb_interface *intf = serial->interface;
> +	int ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
> +
> +	if (ifnum == 1)
> +		tty_port_set_nordy(&port->port, 1);

So s/1/true, provided the parameter is defined as bool now.

thanks,
Johan Hovold Dec. 1, 2020, 8:55 a.m. UTC | #2 
On Tue, Dec 01, 2020 at 07:54:10AM +0100, Jiri Slaby wrote:
> On 30. 11. 20, 16:37, Johan Hovold wrote:
> > --- a/drivers/usb/serial/ftdi_sio.c
> > +++ b/drivers/usb/serial/ftdi_sio.c
> ...
> > @@ -2386,6 +2393,21 @@ static int ftdi_stmclite_probe(struct usb_serial *serial)
> >   	return 0;
> >   }
> >   
> > +/*
> > + * FreeCalypso DUART28C is an FT2232D-based USB to dual UART adapter
> > + * with a special quirk: Channel B RTS and DTR outputs (BDBUS2 and BDBUS4
> > + * on the chip) have been repurposed to drive PWON and RESET controls.
> > + */
> > +static void ftdi_duart28c_setup(struct usb_serial_port *port)
> > +{
> > +	struct usb_serial *serial = port->serial;
> > +	struct usb_interface *intf = serial->interface;
> > +	int ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
> > +
> > +	if (ifnum == 1)
> > +		tty_port_set_nordy(&port->port, 1);
> 
> So s/1/true, provided the parameter is defined as bool now.

Also here I'm following the convention used for the other port-flag
helper which are used with numerical constants (just about) consistently
throughout the tree. 

Johan
diff mbox series

Patch

diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index b69032c9ec2b..b555bbc1b0a9 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -97,6 +97,7 @@  static int   ftdi_stmclite_probe(struct usb_serial *serial);
 static int   ftdi_8u2232c_probe(struct usb_serial *serial);
 static void  ftdi_USB_UIRT_setup(struct usb_serial_port *port);
 static void  ftdi_HE_TIRA1_setup(struct usb_serial_port *port);
+static void  ftdi_duart28c_setup(struct usb_serial_port *port);
 
 static const struct ftdi_sio_quirk ftdi_jtag_quirk = {
 	.probe	= ftdi_jtag_probe,
@@ -122,6 +123,10 @@  static const struct ftdi_sio_quirk ftdi_8u2232c_quirk = {
 	.probe	= ftdi_8u2232c_probe,
 };
 
+static const struct ftdi_sio_quirk ftdi_duart28c_quirk = {
+	.port_probe = ftdi_duart28c_setup,
+};
+
 /*
  * The 8U232AM has the same API as the sio except for:
  * - it can support MUCH higher baudrates; up to:
@@ -1042,6 +1047,8 @@  static const struct usb_device_id id_table_combined[] = {
 		.driver_info = (kernel_ulong_t)&ftdi_jtag_quirk },
 	{ USB_DEVICE(FTDI_VID, FTDI_FALCONIA_JTAG_UNBUF_PID),
 		.driver_info = (kernel_ulong_t)&ftdi_jtag_quirk },
+	{ USB_DEVICE(FTDI_VID, FTDI_FALCONIA_DUART28C_PID),
+		.driver_info = (kernel_ulong_t)&ftdi_duart28c_quirk },
 	{ }					/* Terminating entry */
 };
 
@@ -2386,6 +2393,21 @@  static int ftdi_stmclite_probe(struct usb_serial *serial)
 	return 0;
 }
 
+/*
+ * FreeCalypso DUART28C is an FT2232D-based USB to dual UART adapter
+ * with a special quirk: Channel B RTS and DTR outputs (BDBUS2 and BDBUS4
+ * on the chip) have been repurposed to drive PWON and RESET controls.
+ */
+static void ftdi_duart28c_setup(struct usb_serial_port *port)
+{
+	struct usb_serial *serial = port->serial;
+	struct usb_interface *intf = serial->interface;
+	int ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
+
+	if (ifnum == 1)
+		tty_port_set_nordy(&port->port, 1);
+}
+
 static int ftdi_sio_port_remove(struct usb_serial_port *port)
 {
 	struct ftdi_private *priv = usb_get_serial_port_data(port);
diff --git a/drivers/usb/serial/ftdi_sio_ids.h b/drivers/usb/serial/ftdi_sio_ids.h
index 3d47c6d72256..3081b8916a0a 100644
--- a/drivers/usb/serial/ftdi_sio_ids.h
+++ b/drivers/usb/serial/ftdi_sio_ids.h
@@ -45,6 +45,7 @@ 
  */
 #define FTDI_FALCONIA_JTAG_BUF_PID	0x7150
 #define FTDI_FALCONIA_JTAG_UNBUF_PID	0x7151
+#define FTDI_FALCONIA_DUART28C_PID	0x7152
 
 /* Sienna Serial Interface by Secyourit GmbH */
 #define FTDI_SIENNA_PID		0x8348