From: "Ji-Ze Hong (Peter Hong)" <hpeter@gmail.com>
To: johan@kernel.org
Cc: gregkh@linuxfoundation.org, linux-usb@vger.kernel.org,
linux-kernel@vger.kernel.org, peter_hong@fintek.com.tw,
"Ji-Ze Hong (Peter Hong)" <hpeter+linux_kernel@gmail.com>
Subject: [PATCH V2 5/5] usb: serial: f81534: fix tx error on some baud rate
Date: Thu, 4 Jan 2018 10:29:21 +0800 [thread overview]
Message-ID: <1515032961-29131-5-git-send-email-hpeter+linux_kernel@gmail.com> (raw)
In-Reply-To: <1515032961-29131-1-git-send-email-hpeter+linux_kernel@gmail.com>
The F81532/534 had 4 clocksource 1.846/18.46/14.77/24MHz and baud rates
can be up to 1.5Mbits with 24MHz. But on some baud rate (384~500kps), the
TX side will send the data frame too close to treat frame error on RX
side. This patch will force all TX data frame with delay 1bit gap.
Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
---
V2:
1: First introduced in this series patches.
drivers/usb/serial/f81534.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/usb/serial/f81534.c b/drivers/usb/serial/f81534.c
index a4666171239a..513805eeae6a 100644
--- a/drivers/usb/serial/f81534.c
+++ b/drivers/usb/serial/f81534.c
@@ -130,6 +130,7 @@
#define F81534_CLK_18_46_MHZ (F81534_UART_EN | BIT(1))
#define F81534_CLK_24_MHZ (F81534_UART_EN | BIT(2))
#define F81534_CLK_14_77_MHZ (F81534_UART_EN | BIT(1) | BIT(2))
+#define F81534_CLK_TX_DELAY_1BIT BIT(3)
#define F81534_CLK_RS485_MODE BIT(4)
#define F81534_CLK_RS485_INVERT BIT(5)
@@ -1438,6 +1439,11 @@ static int f81534_port_probe(struct usb_serial_port *port)
break;
}
+ /*
+ * We'll make tx frame error when baud rate from 384~500kps. So we'll
+ * delay all tx data frame with 1bit.
+ */
+ port_priv->shadow_clk |= F81534_CLK_TX_DELAY_1BIT;
return f81534_set_port_output_pin(port);
}
--
2.7.4
next prev parent reply other threads:[~2018-01-04 2:29 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-01-04 2:29 [PATCH V2 1/5] usb: serial: f81534: add high baud rate support Ji-Ze Hong (Peter Hong)
2018-01-04 2:29 ` [PATCH V2 2/5] usb: serial: f81534: add auto RTS direction support Ji-Ze Hong (Peter Hong)
2018-01-09 11:14 ` Johan Hovold
2018-01-04 2:29 ` [PATCH V2 3/5] usb: serial: f81534: add output pin control Ji-Ze Hong (Peter Hong)
2018-01-09 11:19 ` Johan Hovold
2018-01-04 2:29 ` [PATCH V2 4/5] usb: serial: f81534: add H/W disable port support Ji-Ze Hong (Peter Hong)
2018-01-09 11:29 ` Johan Hovold
2018-01-04 2:29 ` Ji-Ze Hong (Peter Hong) [this message]
2018-01-09 11:32 ` [PATCH V2 5/5] usb: serial: f81534: fix tx error on some baud rate Johan Hovold
2018-01-10 5:42 ` Ji-Ze Hong (Peter Hong)
2018-01-10 8:50 ` Johan Hovold
2018-01-09 11:08 ` [PATCH V2 1/5] usb: serial: f81534: add high baud rate support Johan Hovold
2018-01-10 5:30 ` Ji-Ze Hong (Peter Hong)
2018-01-10 8:49 ` Johan Hovold
2018-01-10 9:16 ` Ji-Ze Hong (Peter Hong)
2018-01-10 9:27 ` Johan Hovold
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=1515032961-29131-5-git-send-email-hpeter+linux_kernel@gmail.com \
--to=hpeter@gmail.com \
--cc=gregkh@linuxfoundation.org \
--cc=hpeter+linux_kernel@gmail.com \
--cc=johan@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=peter_hong@fintek.com.tw \
/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).