Merge tag 'usb-serial-6.2-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-next

Johan writes:

USB-serial updates for 6.2-rc1

Here are the USB-serial updates for 6.2-rc1, including:

- B0 hangup support for cp210x
- avoid requesting a zero DTE rate which could potentially confuse
buggy firmware in XR devices

Included are also some new device ids.

All have been in linux-next with no reported issues.

* tag 'usb-serial-6.2-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
USB: serial: xr: avoid requesting zero DTE rate
USB: serial: cp210x: add support for B0 hangup
USB: serial: cp210x: add Kamstrup RF sniffer PIDs
USB: serial: option: add Quectel EM05-G modem

drivers/usb/serial/cp210x.c

···
 	{ USB_DEVICE(0x16DC, 0x0015) }, /* W-IE-NE-R Plein & Baus GmbH CML Control, Monitoring and Data Logger */
 	{ USB_DEVICE(0x17A8, 0x0001) }, /* Kamstrup Optical Eye/3-wire */
 	{ USB_DEVICE(0x17A8, 0x0005) }, /* Kamstrup M-Bus Master MultiPort 250D */
+	{ USB_DEVICE(0x17A8, 0x0011) }, /* Kamstrup 444 MHz RF sniffer */
+	{ USB_DEVICE(0x17A8, 0x0013) }, /* Kamstrup 870 MHz RF sniffer */
 	{ USB_DEVICE(0x17A8, 0x0101) }, /* Kamstrup 868 MHz wM-Bus C-Mode Meter Reader (Int Ant) */
 	{ USB_DEVICE(0x17A8, 0x0102) }, /* Kamstrup 868 MHz wM-Bus C-Mode Meter Reader (Ext Ant) */
 	{ USB_DEVICE(0x17F4, 0xAAAA) }, /* Wavesense Jazz blood glucose meter */
···
 	struct cp210x_serial_private *priv = usb_get_serial_data(serial);
 	u32 baud;
 
+	if (tty->termios.c_ospeed == 0)
+		return;
+
 	/*
 	 * This maps the requested rate to the actual rate, a valid rate on
 	 * cp2102 or cp2103, or to an arbitrary rate in [1M, max_speed].
-	 *
-	 * NOTE: B0 is not implemented.
 	 */
 	baud = clamp(tty->termios.c_ospeed, priv->min_speed, priv->max_speed);
 
···
 		tty->termios.c_iflag &= ~(IXON | IXOFF);
 	}
 
-	if (old_termios &&
+	if (tty->termios.c_ospeed != 0 &&
+			old_termios && old_termios->c_ospeed != 0 &&
 			C_CRTSCTS(tty) == (old_termios->c_cflag & CRTSCTS) &&
 			I_IXON(tty) == (old_termios->c_iflag & IXON) &&
 			I_IXOFF(tty) == (old_termios->c_iflag & IXOFF) &&
···
 	}
 
 	mutex_lock(&port_priv->mutex);
+
+	if (tty->termios.c_ospeed == 0) {
+		port_priv->dtr = false;
+		port_priv->rts = false;
+	} else if (old_termios && old_termios->c_ospeed == 0) {
+		port_priv->dtr = true;
+		port_priv->rts = true;
+	}
 
 	ret = cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
 			sizeof(flow_ctl));
···
 	u16 bits;
 	int ret;
 
-	if (old_termios && !cp210x_termios_change(&tty->termios, old_termios))
+	if (old_termios && !cp210x_termios_change(&tty->termios, old_termios) &&
+			tty->termios.c_ospeed != 0)
 		return;
 
 	if (!old_termios || tty->termios.c_ospeed != old_termios->c_ospeed)

drivers/usb/serial/option.c

···
 #define QUECTEL_PRODUCT_EP06			0x0306
 #define QUECTEL_PRODUCT_EM05G			0x030a
 #define QUECTEL_PRODUCT_EM060K			0x030b
+#define QUECTEL_PRODUCT_EM05G_SG		0x0311
 #define QUECTEL_PRODUCT_EM12			0x0512
 #define QUECTEL_PRODUCT_RM500Q			0x0800
 #define QUECTEL_PRODUCT_RM520N			0x0801
···
 	  .driver_info = RSVD(1) | RSVD(2) | RSVD(3) | RSVD(4) | NUMEP2 },
 	{ USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EP06, 0xff, 0, 0) },
 	{ USB_DEVICE_INTERFACE_CLASS(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EM05G, 0xff),
+	  .driver_info = RSVD(6) | ZLP },
+	{ USB_DEVICE_INTERFACE_CLASS(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EM05G_SG, 0xff),
 	  .driver_info = RSVD(6) | ZLP },
 	{ USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EM060K, 0xff, 0x00, 0x40) },
 	{ USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EM060K, 0xff, 0xff, 0x30) },

drivers/usb/serial/xr_serial.c

···
 
 	if (tty->termios.c_ospeed)
 		lc->dwDTERate = cpu_to_le32(tty->termios.c_ospeed);
-	else if (old_termios)
-		lc->dwDTERate = cpu_to_le32(old_termios->c_ospeed);
 	else
 		lc->dwDTERate = cpu_to_le32(9600);