From d84e27d87738634b92001500435ae4dadba10a13 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?J=C3=A9r=C3=A9my=20Carrat?= Date: Thu, 10 Sep 2026 18:26:09 +0200 Subject: [PATCH 1/3] USB: serial: cp210x: add Corsair AX1500i Power Supply MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The Corsair AX1500i power supply exposes its Corsair Link monitoring interface on a mini-USB port through an on-board CP2103, using a Corsair-specific product ID. Without the ID in the table no driver binds and no tty is created. Tested by forcing the driver association with echo 1b1c 1c02 > /sys/bus/usb-serial/drivers/cp210x/new_id and then setting the serial port to 115200 8N1. Adding the ID is sufficient to talk to the device: the tty reaches a USB-to-SMBus bridge sitting behind the UART, which identifies itself as "USB to SMB Bridge (Firmware by Ross Fosler)" version 0.9 and relays PMBus reads to the power supply controller. Input voltage and current, input and output power, internal temperature and fan speed were all read back on an AX1500i. [ 7.806181] usb 3-14: New USB device found, idVendor=1b1c, idProduct=1c02, bcdDevice= 1.00 [ 698.526754] usbcore: registered new interface driver cp210x [ 698.526767] usbserial: USB Serial support registered for cp210x [ 698.527863] cp210x 3-14:1.0: cp210x converter detected [ 698.529263] usb 3-14: cp210x converter now attached to ttyUSB0 The related AX1600i (1b1c:1c11, iProduct "USB API") is expected to be the same kind of device but has not been tested here, so it is not added. Cc: stable@vger.kernel.org Signed-off-by: Jérémy Carrat Signed-off-by: Johan Hovold --- drivers/usb/serial/cp210x.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c index 333b8b463704..c3f9add98333 100644 --- a/drivers/usb/serial/cp210x.c +++ b/drivers/usb/serial/cp210x.c @@ -223,6 +223,7 @@ static const struct usb_device_id id_table[] = { { USB_DEVICE(0x19CF, 0x3000) }, /* Parrot NMEA GPS Flight Recorder */ { USB_DEVICE(0x1ADB, 0x0001) }, /* Schweitzer Engineering C662 Cable */ { USB_DEVICE(0x1B1C, 0x1C00) }, /* Corsair USB Dongle */ + { USB_DEVICE(0x1B1C, 0x1C02) }, /* Corsair AX1500i Power Supply */ { USB_DEVICE(0x1B93, 0x1013) }, /* Phoenix Contact UPS Device */ { USB_DEVICE(0x1BA4, 0x0002) }, /* Silicon Labs 358x factory default */ { USB_DEVICE(0x1BE3, 0x07A6) }, /* WAGO 750-923 USB Service Cable */ From afc235a217360c6859068d2e37a4df305c4d1be2 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Tue, 15 Sep 2026 14:40:11 +0200 Subject: [PATCH 2/3] USB: serial: ssu100: fix baud rate overflow The requested baud rate is incorrectly truncated to 16 bits so that line speeds above 65535 bps cannot be set. Use 32 bits for the rate and remainder while rejecting rates outside of [50,460800] to avoid having the divisor or remainder overflow. This issue was flagged by an LLM. Fixes: 52af95459939 ("USB: add USB serial ssu100 driver") Cc: stable@vger.kernel.org # 2.6.36 Cc: Bill Pemberton Assisted-by: LLM Signed-off-by: Johan Hovold --- drivers/usb/serial/ssu100.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/drivers/usb/serial/ssu100.c b/drivers/usb/serial/ssu100.c index b0d51558b73c..8c5b9ef708b3 100644 --- a/drivers/usb/serial/ssu100.c +++ b/drivers/usb/serial/ssu100.c @@ -32,6 +32,7 @@ #define SERIAL_EVEN_PARITY (UART_LCR_PARITY | UART_LCR_EPAR) +#define MIN_BAUD_RATE 50 #define MAX_BAUD_RATE 460800 #define ATC_DISABLED 0x00 @@ -217,9 +218,10 @@ static void ssu100_set_termios(struct tty_struct *tty, { struct usb_device *dev = port->serial->dev; struct ktermios *termios = &tty->termios; - u16 baud, divisor, remainder; + speed_t baud, remainder; unsigned int cflag = termios->c_cflag; u16 urb_value = 0; /* will hold the new flags */ + u16 divisor; int result; if (cflag & PARENB) { @@ -235,6 +237,18 @@ static void ssu100_set_termios(struct tty_struct *tty, if (!baud) baud = 9600; + if (baud < MIN_BAUD_RATE || baud > MAX_BAUD_RATE) { + if (old_termios) + baud = tty_termios_baud_rate(old_termios); + else + baud = clamp(baud, MIN_BAUD_RATE, MAX_BAUD_RATE); + + tty_encode_baud_rate(tty, baud, baud); + + if (!baud) + baud = 9600; + } + dev_dbg(&port->dev, "%s - got baud = %d\n", __func__, baud); @@ -310,7 +324,7 @@ static int ssu100_open(struct tty_struct *tty, struct usb_serial_port *port) dev_dbg(&port->dev, "%s - set uart failed\n", __func__); if (tty) - ssu100_set_termios(tty, port, &tty->termios); + ssu100_set_termios(tty, port, NULL); return usb_serial_generic_open(tty, port); } From ec06546b43b612cefc851558981b4955c0ef9e46 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Tue, 15 Sep 2026 14:40:12 +0200 Subject: [PATCH 3/3] USB: serial: quatech2: fix baud rate overflow The requested baud rate is incorrectly truncated to 16 bits so that line speeds above 65535 bps cannot be set. Use 32 bits for the rate while rejecting rates outside of [50,921600] to avoid having the 16-bit divisor overflow. Fixes: f7a33e608d9a ("USB: serial: add quatech2 usb to serial driver") Cc: stable@vger.kernel.org # 3.5 Cc: Bill Pemberton Signed-off-by: Johan Hovold --- drivers/usb/serial/quatech2.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/drivers/usb/serial/quatech2.c b/drivers/usb/serial/quatech2.c index dc2b39810a26..3b4df3ac7c73 100644 --- a/drivers/usb/serial/quatech2.c +++ b/drivers/usb/serial/quatech2.c @@ -52,6 +52,7 @@ #define QT2_XMIT_FLUSH 0x05 /* no following info */ #define QT2_CONTROL_ESCAPE 0xff /* pass through previous 2 control bytes */ +#define MIN_BAUD_RATE 50 #define MAX_BAUD_RATE 921600 #define DEFAULT_BAUD_RATE 9600 @@ -156,7 +157,7 @@ static inline int calc_baud_divisor(int baudrate) static inline int qt2_set_port_config(struct usb_device *dev, unsigned char port_number, - u16 baudrate, u16 lcr) + speed_t baudrate, u16 lcr) { int divisor = calc_baud_divisor(baudrate); u16 index = ((u16) (lcr << 8) | (u16) (port_number)); @@ -257,9 +258,9 @@ static void qt2_set_termios(struct tty_struct *tty, struct usb_device *dev = port->serial->dev; struct qt2_port_private *port_priv; struct ktermios *termios = &tty->termios; - u16 baud; unsigned int cflag = termios->c_cflag; u16 new_lcr = 0; + speed_t baud; int status; port_priv = usb_get_serial_port_data(port); @@ -277,6 +278,18 @@ static void qt2_set_termios(struct tty_struct *tty, if (!baud) baud = 9600; + if (baud < MIN_BAUD_RATE || baud > MAX_BAUD_RATE) { + if (old_termios) + baud = tty_termios_baud_rate(old_termios); + else + baud = clamp(baud, MIN_BAUD_RATE, MAX_BAUD_RATE); + + tty_encode_baud_rate(tty, baud, baud); + + if (!baud) + baud = 9600; + } + status = qt2_set_port_config(dev, port_priv->device_port, baud, new_lcr); if (status < 0) @@ -373,7 +386,7 @@ static int qt2_open(struct tty_struct *tty, struct usb_serial_port *port) port_priv->device_port = (u8) device_port; if (tty) - qt2_set_termios(tty, port, &tty->termios); + qt2_set_termios(tty, port, NULL); return 0;