Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 727 insertions, 0 deletions

diff --git a/drivers/net/hamradio/baycom_ser_hdx.c b/drivers/net/hamradio/baycom_ser_hdx.c
new file mode 100644
index 000000000..5d1ab4840
--- /dev/null
+++ b/drivers/net/hamradio/baycom_ser_hdx.c
@@ -0,0 +1,727 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*****************************************************************************/
+
+/*
+ *	baycom_ser_hdx.c  -- baycom ser12 halfduplex radio modem driver.
+ *
+ *	Copyright (C) 1996-2000  Thomas Sailer (sailer@ife.ee.ethz.ch)
+ *
+ *  Please note that the GPL allows you to use the driver, NOT the radio.
+ *  In order to use the radio, you need a license from the communications
+ *  authority of your country.
+ *
+ *  Supported modems
+ *
+ *  ser12:  This is a very simple 1200 baud AFSK modem. The modem consists only
+ *          of a modulator/demodulator chip, usually a TI TCM3105. The computer
+ *          is responsible for regenerating the receiver bit clock, as well as
+ *          for handling the HDLC protocol. The modem connects to a serial port,
+ *          hence the name. Since the serial port is not used as an async serial
+ *          port, the kernel driver for serial ports cannot be used, and this
+ *          driver only supports standard serial hardware (8250, 16450, 16550A)
+ *
+ *  Command line options (insmod command line)
+ *
+ *  mode     ser12    hardware DCD
+ *           ser12*   software DCD
+ *           ser12@   hardware/software DCD, i.e. no explicit DCD signal but hardware
+ *                    mutes audio input to the modem
+ *           ser12+   hardware DCD, inverted signal at DCD pin
+ *  iobase   base address of the port; common values are 0x3f8, 0x2f8, 0x3e8, 0x2e8
+ *  irq      interrupt line of the port; common values are 4,3
+ *
+ *  History:
+ *   0.1  26.06.1996  Adapted from baycom.c and made network driver interface
+ *        18.10.1996  Changed to new user space access routines (copy_{to,from}_user)
+ *   0.3  26.04.1997  init code/data tagged
+ *   0.4  08.07.1997  alternative ser12 decoding algorithm (uses delta CTS ints)
+ *   0.5  11.11.1997  ser12/par96 split into separate files
+ *   0.6  14.04.1998  cleanups
+ *   0.7  03.08.1999  adapt to Linus' new __setup/__initcall
+ *   0.8  10.08.1999  use module_init/module_exit
+ *   0.9  12.02.2000  adapted to softnet driver interface
+ *   0.10 03.07.2000  fix interface name handling
+ */
+
+/*****************************************************************************/
+
+#include <linux/capability.h>
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/uaccess.h>
+#include <asm/io.h>
+#include <linux/hdlcdrv.h>
+#include <linux/baycom.h>
+#include <linux/jiffies.h>
+
+/* --------------------------------------------------------------------- */
+
+#define BAYCOM_DEBUG
+
+/* --------------------------------------------------------------------- */
+
+static const char bc_drvname[] = "baycom_ser_hdx";
+static const char bc_drvinfo[] = KERN_INFO "baycom_ser_hdx: (C) 1996-2000 Thomas Sailer, HB9JNX/AE4WA\n"
+"baycom_ser_hdx: version 0.10\n";
+
+/* --------------------------------------------------------------------- */
+
+#define NR_PORTS 4
+
+static struct net_device *baycom_device[NR_PORTS];
+
+/* --------------------------------------------------------------------- */
+
+#define RBR(iobase) (iobase+0)
+#define THR(iobase) (iobase+0)
+#define IER(iobase) (iobase+1)
+#define IIR(iobase) (iobase+2)
+#define FCR(iobase) (iobase+2)
+#define LCR(iobase) (iobase+3)
+#define MCR(iobase) (iobase+4)
+#define LSR(iobase) (iobase+5)
+#define MSR(iobase) (iobase+6)
+#define SCR(iobase) (iobase+7)
+#define DLL(iobase) (iobase+0)
+#define DLM(iobase) (iobase+1)
+
+#define SER12_EXTENT 8
+
+/* ---------------------------------------------------------------------- */
+/*
+ * Information that need to be kept for each board.
+ */
+
+struct baycom_state {
+	struct hdlcdrv_state hdrv;
+
+	int opt_dcd;
+
+	struct modem_state {
+		short arb_divider;
+		unsigned char flags;
+		unsigned int shreg;
+		struct modem_state_ser12 {
+			unsigned char tx_bit;
+			int dcd_sum0, dcd_sum1, dcd_sum2;
+			unsigned char last_sample;
+			unsigned char last_rxbit;
+			unsigned int dcd_shreg;
+			unsigned int dcd_time;
+			unsigned int bit_pll;
+			unsigned char interm_sample;
+		} ser12;
+	} modem;
+
+#ifdef BAYCOM_DEBUG
+	struct debug_vals {
+		unsigned long last_jiffies;
+		unsigned cur_intcnt;
+		unsigned last_intcnt;
+		int cur_pllcorr;
+		int last_pllcorr;
+	} debug_vals;
+#endif /* BAYCOM_DEBUG */
+};
+
+/* --------------------------------------------------------------------- */
+
+static inline void baycom_int_freq(struct baycom_state *bc)
+{
+#ifdef BAYCOM_DEBUG
+	unsigned long cur_jiffies = jiffies;
+	/*
+	 * measure the interrupt frequency
+	 */
+	bc->debug_vals.cur_intcnt++;
+	if (time_after_eq(cur_jiffies, bc->debug_vals.last_jiffies + HZ)) {
+		bc->debug_vals.last_jiffies = cur_jiffies;
+		bc->debug_vals.last_intcnt = bc->debug_vals.cur_intcnt;
+		bc->debug_vals.cur_intcnt = 0;
+		bc->debug_vals.last_pllcorr = bc->debug_vals.cur_pllcorr;
+		bc->debug_vals.cur_pllcorr = 0;
+	}
+#endif /* BAYCOM_DEBUG */
+}
+
+/* --------------------------------------------------------------------- */
+/*
+ * ===================== SER12 specific routines =========================
+ */
+
+static inline void ser12_set_divisor(struct net_device *dev,
+				     unsigned char divisor)
+{
+	outb(0x81, LCR(dev->base_addr));	/* DLAB = 1 */
+	outb(divisor, DLL(dev->base_addr));
+	outb(0, DLM(dev->base_addr));
+	outb(0x01, LCR(dev->base_addr));	/* word length = 6 */
+	/*
+	 * make sure the next interrupt is generated;
+	 * 0 must be used to power the modem; the modem draws its
+	 * power from the TxD line
+	 */
+	outb(0x00, THR(dev->base_addr));
+	/*
+	 * it is important not to set the divider while transmitting;
+	 * this reportedly makes some UARTs generating interrupts
+	 * in the hundredthousands per second region
+	 * Reported by: Ignacio.Arenaza@studi.epfl.ch (Ignacio Arenaza Nuno)
+	 */
+}
+
+/* --------------------------------------------------------------------- */
+
+/*
+ * must call the TX arbitrator every 10ms
+ */
+#define SER12_ARB_DIVIDER(bc)  (bc->opt_dcd ? 24 : 36)
+			       
+#define SER12_DCD_INTERVAL(bc) (bc->opt_dcd ? 12 : 240)
+
+static inline void ser12_tx(struct net_device *dev, struct baycom_state *bc)
+{
+	/* one interrupt per channel bit */
+	ser12_set_divisor(dev, 12);
+	/*
+	 * first output the last bit (!) then call HDLC transmitter,
+	 * since this may take quite long
+	 */
+	outb(0x0e | (!!bc->modem.ser12.tx_bit), MCR(dev->base_addr));
+	if (bc->modem.shreg <= 1)
+		bc->modem.shreg = 0x10000 | hdlcdrv_getbits(&bc->hdrv);
+	bc->modem.ser12.tx_bit = !(bc->modem.ser12.tx_bit ^
+				   (bc->modem.shreg & 1));
+	bc->modem.shreg >>= 1;
+}
+
+/* --------------------------------------------------------------------- */
+
+static inline void ser12_rx(struct net_device *dev, struct baycom_state *bc)
+{
+	unsigned char cur_s;
+	/*
+	 * do demodulator
+	 */
+	cur_s = inb(MSR(dev->base_addr)) & 0x10;	/* the CTS line */
+	hdlcdrv_channelbit(&bc->hdrv, cur_s);
+	bc->modem.ser12.dcd_shreg = (bc->modem.ser12.dcd_shreg << 1) |
+		(cur_s != bc->modem.ser12.last_sample);
+	bc->modem.ser12.last_sample = cur_s;
+	if(bc->modem.ser12.dcd_shreg & 1) {
+		if (!bc->opt_dcd) {
+			unsigned int dcdspos, dcdsneg;
+
+			dcdspos = dcdsneg = 0;
+			dcdspos += ((bc->modem.ser12.dcd_shreg >> 1) & 1);
+			if (!(bc->modem.ser12.dcd_shreg & 0x7ffffffe))
+				dcdspos += 2;
+			dcdsneg += ((bc->modem.ser12.dcd_shreg >> 2) & 1);
+			dcdsneg += ((bc->modem.ser12.dcd_shreg >> 3) & 1);
+			dcdsneg += ((bc->modem.ser12.dcd_shreg >> 4) & 1);
+
+			bc->modem.ser12.dcd_sum0 += 16*dcdspos - dcdsneg;
+		} else
+			bc->modem.ser12.dcd_sum0--;
+	}
+	if(!bc->modem.ser12.dcd_time) {
+		hdlcdrv_setdcd(&bc->hdrv, (bc->modem.ser12.dcd_sum0 +
+					   bc->modem.ser12.dcd_sum1 +
+					   bc->modem.ser12.dcd_sum2) < 0);
+		bc->modem.ser12.dcd_sum2 = bc->modem.ser12.dcd_sum1;
+		bc->modem.ser12.dcd_sum1 = bc->modem.ser12.dcd_sum0;
+		/* offset to ensure DCD off on silent input */
+		bc->modem.ser12.dcd_sum0 = 2;
+		bc->modem.ser12.dcd_time = SER12_DCD_INTERVAL(bc);
+	}
+	bc->modem.ser12.dcd_time--;
+	if (!bc->opt_dcd) {
+		/*
+		 * PLL code for the improved software DCD algorithm
+		 */
+		if (bc->modem.ser12.interm_sample) {
+			/*
+			 * intermediate sample; set timing correction to normal
+			 */
+			ser12_set_divisor(dev, 4);
+		} else {
+			/*
+			 * do PLL correction and call HDLC receiver
+			 */
+			switch (bc->modem.ser12.dcd_shreg & 7) {
+			case 1: /* transition too late */
+				ser12_set_divisor(dev, 5);
+#ifdef BAYCOM_DEBUG
+				bc->debug_vals.cur_pllcorr++;
+#endif /* BAYCOM_DEBUG */
+				break;
+			case 4:	/* transition too early */
+				ser12_set_divisor(dev, 3);
+#ifdef BAYCOM_DEBUG
+				bc->debug_vals.cur_pllcorr--;
+#endif /* BAYCOM_DEBUG */
+				break;
+			default:
+				ser12_set_divisor(dev, 4);
+				break;
+			}
+			bc->modem.shreg >>= 1;
+			if (bc->modem.ser12.last_sample ==
+			    bc->modem.ser12.last_rxbit)
+				bc->modem.shreg |= 0x10000;
+			bc->modem.ser12.last_rxbit =
+				bc->modem.ser12.last_sample;
+		}
+		if (++bc->modem.ser12.interm_sample >= 3)
+			bc->modem.ser12.interm_sample = 0;
+		/*
+		 * DCD stuff
+		 */
+		if (bc->modem.ser12.dcd_shreg & 1) {
+			unsigned int dcdspos, dcdsneg;
+
+			dcdspos = dcdsneg = 0;
+			dcdspos += ((bc->modem.ser12.dcd_shreg >> 1) & 1);
+			dcdspos += (!(bc->modem.ser12.dcd_shreg & 0x7ffffffe))
+				<< 1;
+			dcdsneg += ((bc->modem.ser12.dcd_shreg >> 2) & 1);
+			dcdsneg += ((bc->modem.ser12.dcd_shreg >> 3) & 1);
+			dcdsneg += ((bc->modem.ser12.dcd_shreg >> 4) & 1);
+
+			bc->modem.ser12.dcd_sum0 += 16*dcdspos - dcdsneg;
+		}
+	} else {
+		/*
+		 * PLL algorithm for the hardware squelch DCD algorithm
+		 */
+		if (bc->modem.ser12.interm_sample) {
+			/*
+			 * intermediate sample; set timing correction to normal
+			 */
+			ser12_set_divisor(dev, 6);
+		} else {
+			/*
+			 * do PLL correction and call HDLC receiver
+			 */
+			switch (bc->modem.ser12.dcd_shreg & 3) {
+			case 1: /* transition too late */
+				ser12_set_divisor(dev, 7);
+#ifdef BAYCOM_DEBUG
+				bc->debug_vals.cur_pllcorr++;
+#endif /* BAYCOM_DEBUG */
+				break;
+			case 2:	/* transition too early */
+				ser12_set_divisor(dev, 5);
+#ifdef BAYCOM_DEBUG
+				bc->debug_vals.cur_pllcorr--;
+#endif /* BAYCOM_DEBUG */
+				break;
+			default:
+				ser12_set_divisor(dev, 6);
+				break;
+			}
+			bc->modem.shreg >>= 1;
+			if (bc->modem.ser12.last_sample ==
+			    bc->modem.ser12.last_rxbit)
+				bc->modem.shreg |= 0x10000;
+			bc->modem.ser12.last_rxbit =
+				bc->modem.ser12.last_sample;
+		}
+		bc->modem.ser12.interm_sample = !bc->modem.ser12.interm_sample;
+		/*
+		 * DCD stuff
+		 */
+		bc->modem.ser12.dcd_sum0 -= (bc->modem.ser12.dcd_shreg & 1);
+	}
+	outb(0x0d, MCR(dev->base_addr));		/* transmitter off */
+	if (bc->modem.shreg & 1) {
+		hdlcdrv_putbits(&bc->hdrv, bc->modem.shreg >> 1);
+		bc->modem.shreg = 0x10000;
+	}
+	if(!bc->modem.ser12.dcd_time) {
+		if (bc->opt_dcd & 1) 
+			hdlcdrv_setdcd(&bc->hdrv, !((inb(MSR(dev->base_addr)) ^ bc->opt_dcd) & 0x80));
+		else
+			hdlcdrv_setdcd(&bc->hdrv, (bc->modem.ser12.dcd_sum0 +
+						   bc->modem.ser12.dcd_sum1 +
+						   bc->modem.ser12.dcd_sum2) < 0);
+		bc->modem.ser12.dcd_sum2 = bc->modem.ser12.dcd_sum1;
+		bc->modem.ser12.dcd_sum1 = bc->modem.ser12.dcd_sum0;
+		/* offset to ensure DCD off on silent input */
+		bc->modem.ser12.dcd_sum0 = 2;
+		bc->modem.ser12.dcd_time = SER12_DCD_INTERVAL(bc);
+	}
+	bc->modem.ser12.dcd_time--;
+}
+
+/* --------------------------------------------------------------------- */
+
+static irqreturn_t ser12_interrupt(int irq, void *dev_id)
+{
+	struct net_device *dev = (struct net_device *)dev_id;
+	struct baycom_state *bc = netdev_priv(dev);
+	unsigned char iir;
+
+	if (!dev || !bc || bc->hdrv.magic != HDLCDRV_MAGIC)
+		return IRQ_NONE;
+	/* fast way out */
+	if ((iir = inb(IIR(dev->base_addr))) & 1)
+		return IRQ_NONE;
+	baycom_int_freq(bc);
+	do {
+		switch (iir & 6) {
+		case 6:
+			inb(LSR(dev->base_addr));
+			break;
+			
+		case 4:
+			inb(RBR(dev->base_addr));
+			break;
+			
+		case 2:
+			/*
+			 * check if transmitter active
+			 */
+			if (hdlcdrv_ptt(&bc->hdrv))
+				ser12_tx(dev, bc);
+			else {
+				ser12_rx(dev, bc);
+				bc->modem.arb_divider--;
+			}
+			outb(0x00, THR(dev->base_addr));
+			break;
+			
+		default:
+			inb(MSR(dev->base_addr));
+			break;
+		}
+		iir = inb(IIR(dev->base_addr));
+	} while (!(iir & 1));
+	if (bc->modem.arb_divider <= 0) {
+		bc->modem.arb_divider = SER12_ARB_DIVIDER(bc);
+		local_irq_enable();
+		hdlcdrv_arbitrate(dev, &bc->hdrv);
+	}
+	local_irq_enable();
+	hdlcdrv_transmitter(dev, &bc->hdrv);
+	hdlcdrv_receiver(dev, &bc->hdrv);
+	local_irq_disable();
+	return IRQ_HANDLED;
+}
+
+/* --------------------------------------------------------------------- */
+
+enum uart { c_uart_unknown, c_uart_8250,
+	    c_uart_16450, c_uart_16550, c_uart_16550A};
+static const char *uart_str[] = { 
+	"unknown", "8250", "16450", "16550", "16550A" 
+};
+
+static enum uart ser12_check_uart(unsigned int iobase)
+{
+	unsigned char b1,b2,b3;
+	enum uart u;
+	enum uart uart_tab[] =
+		{ c_uart_16450, c_uart_unknown, c_uart_16550, c_uart_16550A };
+
+	b1 = inb(MCR(iobase));
+	outb(b1 | 0x10, MCR(iobase));	/* loopback mode */
+	b2 = inb(MSR(iobase));
+	outb(0x1a, MCR(iobase));
+	b3 = inb(MSR(iobase)) & 0xf0;
+	outb(b1, MCR(iobase));			/* restore old values */
+	outb(b2, MSR(iobase));
+	if (b3 != 0x90)
+		return c_uart_unknown;
+	inb(RBR(iobase));
+	inb(RBR(iobase));
+	outb(0x01, FCR(iobase));		/* enable FIFOs */
+	u = uart_tab[(inb(IIR(iobase)) >> 6) & 3];
+	if (u == c_uart_16450) {
+		outb(0x5a, SCR(iobase));
+		b1 = inb(SCR(iobase));
+		outb(0xa5, SCR(iobase));
+		b2 = inb(SCR(iobase));
+		if ((b1 != 0x5a) || (b2 != 0xa5))
+			u = c_uart_8250;
+	}
+	return u;
+}
+
+/* --------------------------------------------------------------------- */
+
+static int ser12_open(struct net_device *dev)
+{
+	struct baycom_state *bc = netdev_priv(dev);
+	enum uart u;
+
+	if (!dev || !bc)
+		return -ENXIO;
+	if (!dev->base_addr || dev->base_addr > 0x1000-SER12_EXTENT ||
+	    dev->irq < 2 || dev->irq > 15)
+		return -ENXIO;
+	if (!request_region(dev->base_addr, SER12_EXTENT, "baycom_ser12"))
+		return -EACCES;
+	memset(&bc->modem, 0, sizeof(bc->modem));
+	bc->hdrv.par.bitrate = 1200;
+	if ((u = ser12_check_uart(dev->base_addr)) == c_uart_unknown) {
+		release_region(dev->base_addr, SER12_EXTENT);       
+		return -EIO;
+	}
+	outb(0, FCR(dev->base_addr));  /* disable FIFOs */
+	outb(0x0d, MCR(dev->base_addr));
+	outb(0, IER(dev->base_addr));
+	if (request_irq(dev->irq, ser12_interrupt, IRQF_SHARED,
+			"baycom_ser12", dev)) {
+		release_region(dev->base_addr, SER12_EXTENT);       
+		return -EBUSY;
+	}
+	/*
+	 * enable transmitter empty interrupt
+	 */
+	outb(2, IER(dev->base_addr));
+	/*
+	 * set the SIO to 6 Bits/character and 19200 or 28800 baud, so that
+	 * we get exactly (hopefully) 2 or 3 interrupts per radio symbol,
+	 * depending on the usage of the software DCD routine
+	 */
+	ser12_set_divisor(dev, bc->opt_dcd ? 6 : 4);
+	printk(KERN_INFO "%s: ser12 at iobase 0x%lx irq %u uart %s\n", 
+	       bc_drvname, dev->base_addr, dev->irq, uart_str[u]);
+	return 0;
+}
+
+/* --------------------------------------------------------------------- */
+
+static int ser12_close(struct net_device *dev)
+{
+	struct baycom_state *bc = netdev_priv(dev);
+
+	if (!dev || !bc)
+		return -EINVAL;
+	/*
+	 * disable interrupts
+	 */
+	outb(0, IER(dev->base_addr));
+	outb(1, MCR(dev->base_addr));
+	free_irq(dev->irq, dev);
+	release_region(dev->base_addr, SER12_EXTENT);
+	printk(KERN_INFO "%s: close ser12 at iobase 0x%lx irq %u\n",
+	       bc_drvname, dev->base_addr, dev->irq);
+	return 0;
+}
+
+/* --------------------------------------------------------------------- */
+/*
+ * ===================== hdlcdrv driver interface =========================
+ */
+
+/* --------------------------------------------------------------------- */
+
+static int baycom_ioctl(struct net_device *dev, void __user *data,
+			struct hdlcdrv_ioctl *hi, int cmd);
+
+/* --------------------------------------------------------------------- */
+
+static const struct hdlcdrv_ops ser12_ops = {
+	.drvname = bc_drvname,
+	.drvinfo = bc_drvinfo,
+	.open    = ser12_open,
+	.close   = ser12_close,
+	.ioctl   = baycom_ioctl,
+};
+
+/* --------------------------------------------------------------------- */
+
+static int baycom_setmode(struct baycom_state *bc, const char *modestr)
+{
+	if (strchr(modestr, '*'))
+		bc->opt_dcd = 0;
+	else if (strchr(modestr, '+'))
+		bc->opt_dcd = -1;
+	else if (strchr(modestr, '@'))
+		bc->opt_dcd = -2;
+	else
+		bc->opt_dcd = 1;
+	return 0;
+}
+
+/* --------------------------------------------------------------------- */
+
+static int baycom_ioctl(struct net_device *dev, void __user *data,
+			struct hdlcdrv_ioctl *hi, int cmd)
+{
+	struct baycom_state *bc;
+	struct baycom_ioctl bi;
+
+	if (!dev)
+		return -EINVAL;
+
+	bc = netdev_priv(dev);
+	BUG_ON(bc->hdrv.magic != HDLCDRV_MAGIC);
+
+	if (cmd != SIOCDEVPRIVATE)
+		return -ENOIOCTLCMD;
+	switch (hi->cmd) {
+	default:
+		break;
+
+	case HDLCDRVCTL_GETMODE:
+		strcpy(hi->data.modename, "ser12");
+		if (bc->opt_dcd <= 0)
+			strcat(hi->data.modename, (!bc->opt_dcd) ? "*" : (bc->opt_dcd == -2) ? "@" : "+");
+		if (copy_to_user(data, hi, sizeof(struct hdlcdrv_ioctl)))
+			return -EFAULT;
+		return 0;
+
+	case HDLCDRVCTL_SETMODE:
+		if (netif_running(dev) || !capable(CAP_NET_ADMIN))
+			return -EACCES;
+		hi->data.modename[sizeof(hi->data.modename)-1] = '\0';
+		return baycom_setmode(bc, hi->data.modename);
+
+	case HDLCDRVCTL_MODELIST:
+		strcpy(hi->data.modename, "ser12");
+		if (copy_to_user(data, hi, sizeof(struct hdlcdrv_ioctl)))
+			return -EFAULT;
+		return 0;
+
+	case HDLCDRVCTL_MODEMPARMASK:
+		return HDLCDRV_PARMASK_IOBASE | HDLCDRV_PARMASK_IRQ;
+
+	}
+
+	if (copy_from_user(&bi, data, sizeof(bi)))
+		return -EFAULT;
+	switch (bi.cmd) {
+	default:
+		return -ENOIOCTLCMD;
+
+#ifdef BAYCOM_DEBUG
+	case BAYCOMCTL_GETDEBUG:
+		bi.data.dbg.debug1 = bc->hdrv.ptt_keyed;
+		bi.data.dbg.debug2 = bc->debug_vals.last_intcnt;
+		bi.data.dbg.debug3 = bc->debug_vals.last_pllcorr;
+		break;
+#endif /* BAYCOM_DEBUG */
+
+	}
+	if (copy_to_user(data, &bi, sizeof(bi)))
+		return -EFAULT;
+	return 0;
+
+}
+
+/* --------------------------------------------------------------------- */
+
+/*
+ * command line settable parameters
+ */
+static char *mode[NR_PORTS] = { "ser12*", };
+static int iobase[NR_PORTS] = { 0x3f8, };
+static int irq[NR_PORTS] = { 4, };
+
+module_param_array(mode, charp, NULL, 0);
+MODULE_PARM_DESC(mode, "baycom operating mode; * for software DCD");
+module_param_hw_array(iobase, int, ioport, NULL, 0);
+MODULE_PARM_DESC(iobase, "baycom io base address");
+module_param_hw_array(irq, int, irq, NULL, 0);
+MODULE_PARM_DESC(irq, "baycom irq number");
+
+MODULE_AUTHOR("Thomas M. Sailer, sailer@ife.ee.ethz.ch, hb9jnx@hb9w.che.eu");
+MODULE_DESCRIPTION("Baycom ser12 half duplex amateur radio modem driver");
+MODULE_LICENSE("GPL");
+
+/* --------------------------------------------------------------------- */
+
+static int __init init_baycomserhdx(void)
+{
+	int i, found = 0;
+	char set_hw = 1;
+
+	printk(bc_drvinfo);
+	/*
+	 * register net devices
+	 */
+	for (i = 0; i < NR_PORTS; i++) {
+		struct net_device *dev;
+		struct baycom_state *bc;
+		char ifname[IFNAMSIZ];
+
+		sprintf(ifname, "bcsh%d", i);
+
+		if (!mode[i])
+			set_hw = 0;
+		if (!set_hw)
+			iobase[i] = irq[i] = 0;
+
+		dev = hdlcdrv_register(&ser12_ops, 
+				       sizeof(struct baycom_state),
+				       ifname, iobase[i], irq[i], 0);
+		if (IS_ERR(dev)) 
+			break;
+
+		bc = netdev_priv(dev);
+		if (set_hw && baycom_setmode(bc, mode[i]))
+			set_hw = 0;
+		found++;
+		baycom_device[i] = dev;
+	}
+
+	if (!found)
+		return -ENXIO;
+	return 0;
+}
+
+static void __exit cleanup_baycomserhdx(void)
+{
+	int i;
+
+	for(i = 0; i < NR_PORTS; i++) {
+		struct net_device *dev = baycom_device[i];
+
+		if (dev)
+			hdlcdrv_unregister(dev);
+	}
+}
+
+module_init(init_baycomserhdx);
+module_exit(cleanup_baycomserhdx);
+
+/* --------------------------------------------------------------------- */
+
+#ifndef MODULE
+
+/*
+ * format: baycom_ser_hdx=io,irq,mode
+ * mode: ser12    hardware DCD
+ *       ser12*   software DCD
+ *       ser12@   hardware/software DCD, i.e. no explicit DCD signal but hardware
+ *                mutes audio input to the modem
+ *       ser12+   hardware DCD, inverted signal at DCD pin
+ */
+
+static int __init baycom_ser_hdx_setup(char *str)
+{
+        static unsigned nr_dev;
+	int ints[3];
+
+        if (nr_dev >= NR_PORTS)
+                return 0;
+	str = get_options(str, 3, ints);
+	if (ints[0] < 2)
+		return 0;
+	mode[nr_dev] = str;
+	iobase[nr_dev] = ints[1];
+	irq[nr_dev] = ints[2];
+	nr_dev++;
+	return 1;
+}
+
+__setup("baycom_ser_hdx=", baycom_ser_hdx_setup);
+
+#endif /* MODULE */
+/* --------------------------------------------------------------------- */