This is a note to let you know that I've just added the patch titled
USB: serial: cp210x: re-enable auto-RTS on open
to my usb git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-next branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will also be merged in the next major kernel release
during the merge window.
If you have any questions about this process, please let me know.
>From c7614ff9b73a1e6fb2b1b51396da132ed22fecdb Mon Sep 17 00:00:00 2001
From: Brant Merryman <brant.merryman(a)silabs.com>
Date: Fri, 26 Jun 2020 04:24:20 +0000
Subject: USB: serial: cp210x: re-enable auto-RTS on open
CP210x hardware disables auto-RTS but leaves auto-CTS when in hardware
flow control mode and UART on cp210x hardware is disabled. When
re-opening the port, if auto-CTS is enabled on the cp210x, then auto-RTS
must be re-enabled in the driver.
Signed-off-by: Brant Merryman <brant.merryman(a)silabs.com>
Co-developed-by: Phu Luu <phu.luu(a)silabs.com>
Signed-off-by: Phu Luu <phu.luu(a)silabs.com>
Link: https://lore.kernel.org/r/ECCF8E73-91F3-4080-BE17-1714BC8818FB@silabs.com
[ johan: fix up tags and problem description ]
Fixes: 39a66b8d22a3 ("[PATCH] USB: CP2101 Add support for flow control")
Cc: stable <stable(a)vger.kernel.org> # 2.6.12
Signed-off-by: Johan Hovold <johan(a)kernel.org>
---
drivers/usb/serial/cp210x.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c
index bcceb4ad8be0..a90801ef0055 100644
--- a/drivers/usb/serial/cp210x.c
+++ b/drivers/usb/serial/cp210x.c
@@ -917,6 +917,7 @@ static void cp210x_get_termios_port(struct usb_serial_port *port,
u32 baud;
u16 bits;
u32 ctl_hs;
+ u32 flow_repl;
cp210x_read_u32_reg(port, CP210X_GET_BAUDRATE, &baud);
@@ -1017,6 +1018,22 @@ static void cp210x_get_termios_port(struct usb_serial_port *port,
ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
if (ctl_hs & CP210X_SERIAL_CTS_HANDSHAKE) {
dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
+ /*
+ * When the port is closed, the CP210x hardware disables
+ * auto-RTS and RTS is deasserted but it leaves auto-CTS when
+ * in hardware flow control mode. When re-opening the port, if
+ * auto-CTS is enabled on the cp210x, then auto-RTS must be
+ * re-enabled in the driver.
+ */
+ flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
+ flow_repl &= ~CP210X_SERIAL_RTS_MASK;
+ flow_repl |= CP210X_SERIAL_RTS_SHIFT(CP210X_SERIAL_RTS_FLOW_CTL);
+ flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
+ cp210x_write_reg_block(port,
+ CP210X_SET_FLOW,
+ &flow_ctl,
+ sizeof(flow_ctl));
+
cflag |= CRTSCTS;
} else {
dev_dbg(dev, "%s - flow control = NONE\n", __func__);
--
2.27.0
This is a note to let you know that I've just added the patch titled
USB: serial: cp210x: enable usb generic throttle/unthrottle
to my usb git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-next branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will also be merged in the next major kernel release
during the merge window.
If you have any questions about this process, please let me know.
>From 4387b3dbb079d482d3c2b43a703ceed4dd27ed28 Mon Sep 17 00:00:00 2001
From: Brant Merryman <brant.merryman(a)silabs.com>
Date: Fri, 26 Jun 2020 04:22:58 +0000
Subject: USB: serial: cp210x: enable usb generic throttle/unthrottle
Assign the .throttle and .unthrottle functions to be generic function
in the driver structure to prevent data loss that can otherwise occur
if the host does not enable USB throttling.
Signed-off-by: Brant Merryman <brant.merryman(a)silabs.com>
Co-developed-by: Phu Luu <phu.luu(a)silabs.com>
Signed-off-by: Phu Luu <phu.luu(a)silabs.com>
Link: https://lore.kernel.org/r/57401AF3-9961-461F-95E1-F8AFC2105F5E@silabs.com
[ johan: fix up tags ]
Fixes: 39a66b8d22a3 ("[PATCH] USB: CP2101 Add support for flow control")
Cc: stable <stable(a)vger.kernel.org> # 2.6.12
Signed-off-by: Johan Hovold <johan(a)kernel.org>
---
drivers/usb/serial/cp210x.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c
index f5143eedbc48..bcceb4ad8be0 100644
--- a/drivers/usb/serial/cp210x.c
+++ b/drivers/usb/serial/cp210x.c
@@ -272,6 +272,8 @@ static struct usb_serial_driver cp210x_device = {
.break_ctl = cp210x_break_ctl,
.set_termios = cp210x_set_termios,
.tx_empty = cp210x_tx_empty,
+ .throttle = usb_serial_generic_throttle,
+ .unthrottle = usb_serial_generic_unthrottle,
.tiocmget = cp210x_tiocmget,
.tiocmset = cp210x_tiocmset,
.attach = cp210x_attach,
--
2.27.0
This is a note to let you know that I've just added the patch titled
USB: serial: cp210x: re-enable auto-RTS on open
to my usb git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-testing branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will be merged to the usb-next branch sometime soon,
after it passes testing, and the merge window is open.
If you have any questions about this process, please let me know.
>From c7614ff9b73a1e6fb2b1b51396da132ed22fecdb Mon Sep 17 00:00:00 2001
From: Brant Merryman <brant.merryman(a)silabs.com>
Date: Fri, 26 Jun 2020 04:24:20 +0000
Subject: USB: serial: cp210x: re-enable auto-RTS on open
CP210x hardware disables auto-RTS but leaves auto-CTS when in hardware
flow control mode and UART on cp210x hardware is disabled. When
re-opening the port, if auto-CTS is enabled on the cp210x, then auto-RTS
must be re-enabled in the driver.
Signed-off-by: Brant Merryman <brant.merryman(a)silabs.com>
Co-developed-by: Phu Luu <phu.luu(a)silabs.com>
Signed-off-by: Phu Luu <phu.luu(a)silabs.com>
Link: https://lore.kernel.org/r/ECCF8E73-91F3-4080-BE17-1714BC8818FB@silabs.com
[ johan: fix up tags and problem description ]
Fixes: 39a66b8d22a3 ("[PATCH] USB: CP2101 Add support for flow control")
Cc: stable <stable(a)vger.kernel.org> # 2.6.12
Signed-off-by: Johan Hovold <johan(a)kernel.org>
---
drivers/usb/serial/cp210x.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c
index bcceb4ad8be0..a90801ef0055 100644
--- a/drivers/usb/serial/cp210x.c
+++ b/drivers/usb/serial/cp210x.c
@@ -917,6 +917,7 @@ static void cp210x_get_termios_port(struct usb_serial_port *port,
u32 baud;
u16 bits;
u32 ctl_hs;
+ u32 flow_repl;
cp210x_read_u32_reg(port, CP210X_GET_BAUDRATE, &baud);
@@ -1017,6 +1018,22 @@ static void cp210x_get_termios_port(struct usb_serial_port *port,
ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
if (ctl_hs & CP210X_SERIAL_CTS_HANDSHAKE) {
dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);
+ /*
+ * When the port is closed, the CP210x hardware disables
+ * auto-RTS and RTS is deasserted but it leaves auto-CTS when
+ * in hardware flow control mode. When re-opening the port, if
+ * auto-CTS is enabled on the cp210x, then auto-RTS must be
+ * re-enabled in the driver.
+ */
+ flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
+ flow_repl &= ~CP210X_SERIAL_RTS_MASK;
+ flow_repl |= CP210X_SERIAL_RTS_SHIFT(CP210X_SERIAL_RTS_FLOW_CTL);
+ flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
+ cp210x_write_reg_block(port,
+ CP210X_SET_FLOW,
+ &flow_ctl,
+ sizeof(flow_ctl));
+
cflag |= CRTSCTS;
} else {
dev_dbg(dev, "%s - flow control = NONE\n", __func__);
--
2.27.0
This is a note to let you know that I've just added the patch titled
USB: serial: cp210x: enable usb generic throttle/unthrottle
to my usb git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-testing branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will be merged to the usb-next branch sometime soon,
after it passes testing, and the merge window is open.
If you have any questions about this process, please let me know.
>From 4387b3dbb079d482d3c2b43a703ceed4dd27ed28 Mon Sep 17 00:00:00 2001
From: Brant Merryman <brant.merryman(a)silabs.com>
Date: Fri, 26 Jun 2020 04:22:58 +0000
Subject: USB: serial: cp210x: enable usb generic throttle/unthrottle
Assign the .throttle and .unthrottle functions to be generic function
in the driver structure to prevent data loss that can otherwise occur
if the host does not enable USB throttling.
Signed-off-by: Brant Merryman <brant.merryman(a)silabs.com>
Co-developed-by: Phu Luu <phu.luu(a)silabs.com>
Signed-off-by: Phu Luu <phu.luu(a)silabs.com>
Link: https://lore.kernel.org/r/57401AF3-9961-461F-95E1-F8AFC2105F5E@silabs.com
[ johan: fix up tags ]
Fixes: 39a66b8d22a3 ("[PATCH] USB: CP2101 Add support for flow control")
Cc: stable <stable(a)vger.kernel.org> # 2.6.12
Signed-off-by: Johan Hovold <johan(a)kernel.org>
---
drivers/usb/serial/cp210x.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c
index f5143eedbc48..bcceb4ad8be0 100644
--- a/drivers/usb/serial/cp210x.c
+++ b/drivers/usb/serial/cp210x.c
@@ -272,6 +272,8 @@ static struct usb_serial_driver cp210x_device = {
.break_ctl = cp210x_break_ctl,
.set_termios = cp210x_set_termios,
.tx_empty = cp210x_tx_empty,
+ .throttle = usb_serial_generic_throttle,
+ .unthrottle = usb_serial_generic_unthrottle,
.tiocmget = cp210x_tiocmget,
.tiocmset = cp210x_tiocmset,
.attach = cp210x_attach,
--
2.27.0