From: Robert Wolters <robert@woltersonline.net>
To: johan@kernel.org
Cc: linux-usb@vger.kernel.org
Subject: Set custom baud-rate for SCS P4 Dragon
Date: Thu, 6 May 2021 10:44:25 +0200 [thread overview]
Message-ID: <20210506104425.96371fb3f743800896605ae4@woltersonline.net> (raw)
Why: FTDI USB serial speed issue with SCS P4 Dragon short-wave modems,
a custom baud-rate is required
Solution: set special baud-rate by setting a custom divisor on 38400B
Signed-off-by: Robert Wolters <robert@woltersonline.net>
--- ftdi_sio.c 2021-04-21 13:01:00.000000000 +0200
+++ ftdi_sio.c 2021-04-26 18:53:00.819175707 +0200
@@ -97,6 +97,7 @@
static int ftdi_8u2232c_probe(struct usb_serial *serial);
static void ftdi_USB_UIRT_setup(struct ftdi_private *priv);
static void ftdi_HE_TIRA1_setup(struct ftdi_private *priv);
+static void ftdi_SCS_DR7X00_setup(struct ftdi_private *priv);
static const struct ftdi_sio_quirk ftdi_jtag_quirk = {
.probe = ftdi_jtag_probe,
@@ -122,6 +123,10 @@
.probe = ftdi_8u2232c_probe,
};
+static const struct ftdi_sio_quirk ftdi_SCS_DR7X00_quirk = {
+ .port_probe = ftdi_SCS_DR7X00_setup,
+};
+
/*
* The 8U232AM has the same API as the sio except for:
* - it can support MUCH higher baudrates; up to:
@@ -157,8 +162,12 @@
{ USB_DEVICE(FTDI_VID, FTDI_EV3CON_PID) },
{ USB_DEVICE(FTDI_VID, FTDI_SCS_DEVICE_0_PID) },
{ USB_DEVICE(FTDI_VID, FTDI_SCS_DEVICE_1_PID) },
- { USB_DEVICE(FTDI_VID, FTDI_SCS_DEVICE_2_PID) },
- { USB_DEVICE(FTDI_VID, FTDI_SCS_DEVICE_3_PID) },
+ { USB_DEVICE(FTDI_VID, FTDI_SCS_DEVICE_2_PID) ,
+ .driver_info = (kernel_ulong_t)&ftdi_SCS_DR7X00_quirk },
+ { USB_DEVICE(FTDI_VID, FTDI_SCS_DEVICE_3_PID) ,
+ .driver_info = (kernel_ulong_t)&ftdi_SCS_DR7X00_quirk },
{ USB_DEVICE(FTDI_VID, FTDI_SCS_DEVICE_4_PID) },
{ USB_DEVICE(FTDI_VID, FTDI_SCS_DEVICE_5_PID) },
{ USB_DEVICE(FTDI_VID, FTDI_SCS_DEVICE_6_PID) },
@@ -2296,6 +2305,15 @@
priv->force_rtscts = 1;
}
+/* Setup for the SCS P4dragon DR-7X00 devices, which require
+ *hardwired baud-rate of 829440 (38400 gets mapped to 829440) */
+static void ftdi_SCS_DR7X00_setup(struct ftdi_private *priv)
+{
+ priv->flags |= ASYNC_SPD_CUST;
+ priv->custom_divisor = 29;
+ priv->force_baud = 38400;
+}
+
/*
* Module parameter to control latency timer for NDI FTDI-based USB devices.
* If this value is not set in /etc/modprobe.d/ its value will be set
next reply other threads:[~2021-05-06 8:44 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-06 8:44 Robert Wolters [this message]
2021-05-10 8:22 ` Set custom baud-rate for SCS P4 Dragon Johan Hovold
-- strict thread matches above, loose matches on Subject: below --
2021-05-06 7:43 set " Robert Wolters
2021-05-06 7:56 ` Greg KH
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210506104425.96371fb3f743800896605ae4@woltersonline.net \
--to=robert@woltersonline.net \
--cc=johan@kernel.org \
--cc=linux-usb@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).